Bearing device for wheel, and axle module

Wheel bearing device and axle module technical field

[0001] The present invention relates to a wheel bearing device for rotatably supporting a wheel relative to a vehicle body in a vehicle such as an automobile, and an axle module using such a wheel bearing device.

Background technique

[0002] In the wheel bearing device, the first-generation single-use multi-row rolling bearing structure has evolved to the second-generation in which the outer part is integrated with the body mounting flange, and the integrated wheel mounting flange has been developed. The third generation in which the outer circumference of the hub ring is integrally formed with the inner rolling surface on one side of the multi-row rolling bearing. In addition, a constant velocity universal joint is integrated on the hub ring to form the outer joint of the constant velocity universal joint. The fourth generation of the other inner rolling surface of the multi-row rolling bearing is integrally formed on the outer circumference of the component.

[0003] For example, Patent Document 1 describes a structure called the third generation. As shown in FIG. 37, the third-generation wheel bearing device has: a hub ring 152 having a flange 151 extending in the outer diameter direction; a constant velocity universal joint member 153 is fixed to the hub ring 152 Joint 154; the outer member 155 arranged on the outer peripheral side of the hub ring 152.

[0004] The constant velocity universal joint 154 has: the outer joint member 153; the inner joint member 158 arranged in the bowl portion 157 of the outer joint member 153; and the inner joint member 158 and the outer joint member 153 between the balls 159; the cage 160 holding the balls 159. In addition, a spline portion 161 is formed on the inner peripheral surface of the center hole of the inner joint member 158, and the end spline portion of the shaft (not shown) is inserted into the center hole. The spline portion 161 on the inner joint member 158 side is connected to the center hole. The spline on the shaft side engages.

[0005] In addition, the hub wheel 152 has a cylindrical portion 163 and the flange 151. The outer end surface 164 (the end surface on the outer side) of the flange 151 is provided with a wheel (not shown) and a brake disc attached thereto. Short cylindrical control unit 165. In addition, the control unit 165 is composed of a large-diameter first portion 165a and a small-diameter second portion 165b. The first portion 165a is fitted with a wheel, and the second portion 165b is fitted with a brake disc.

[0006] In addition, a cut-out portion 166 is provided on the outer peripheral surface of the end portion on the bowl-shaped portion 157 side of the cylindrical portion 163, and the inner ring 167 is fitted into the cut-out portion 166. A first inner raceway surface 168 is provided near the flange of the outer peripheral surface of the cylindrical portion 163 of the hub ring 152, and a second inner raceway surface 169 is provided on the outer peripheral surface of the inner ring 167. In addition, a bolt attaching hole 162 is provided on the flange 151 of the hub ring 152, and a hub bolt for fixing the wheel and the brake disc on the flange 151 is attached to the bolt attaching hole 162.

[0007] The outer member 155 is provided with two rows of outer raceway surfaces 170, 121 on its inner circumference, and a flange (body mounting flange) 182 is provided on the outer circumference. In addition, the first outer raceway surface 170 of the outer member 155 is opposed to the first inner raceway surface 168 of the hub ring 152, and the second outer raceway surface 171 of the outer member 155 is opposed to the raceway surface 169 of the inner ring 167 , The rolling element 172 is interposed between them. That is, the inner member of the rolling bearing is constituted by the inner ring 167 and a part of the outer diameter surface of the hub ring 152.

[0008] The shaft portion 173 of the outer joint member 153 is inserted into the cylindrical portion 163 of the hub wheel 152. The shaft portion 173 has a threaded portion 174 formed on the end of its bowl-shaped opposite portion, and a spline portion 175 is formed between the threaded portion 174 and the bowl-shaped portion 157. In addition, a spline portion 176 is formed on the inner peripheral surface (inner diameter surface) of the cylindrical portion 163 of the hub ring 152. When the shaft portion 173 is inserted into the cylindrical portion 163 of the hub ring 152, the spline portion 175 on the shaft portion 173 side It engages with the spline part 176 on the side of the hub 152.

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[0009] In addition, a nut member 177 is screwed to the threaded portion 174 of the shaft portion 173 protruding from the cylindrical portion 163, and the hub ring 152 is connected to the outer joint member 153. At this time, the inner end surface (rear surface) 178 of the nut member 177 is in contact with the outer end surface 179 of the cylindrical portion 163, and the end surface 180 on the shaft side of the bowl portion 157 is in contact with the outer end surface 181 of the inner ring 167. That is, by tightening the nut member 177, the hub ring 152 is sandwiched by the nut member 177 and the bowl portion 157 via the inner ring 167.

[0010] Patent Document 1: JP 2004-340311 A

[0011] Conventionally, as described above, the spline portion 175 on the shaft portion 173 side and the spline portion 176 on the hub wheel 152 side are engaged. Therefore, it is necessary to perform spline processing on both the shaft portion 173 side and the hub ring 152 side, which increases the cost, and it is necessary to combine the spline portion 175 on the shaft portion 173 side and the spline portion on the hub ring 152 side during press-fitting. The unevenness of the part 176 is anastomosed. At this time, if the uneven tooth is pressed in by the anastomosing tooth surface, the uneven tooth may be damaged (cracked). In addition, if it does not fit the tooth surface, but press-fitting through the large-diameter fit of the concave-convex tooth, it is easy to cause rattling in the circumferential direction. In this way, when there is shaking in the circumferential direction, the transmission of the rotational torque is deteriorated, and noise is also generated. Therefore, when spline fitting is used as in the past, it is difficult to simultaneously establish the damage of the uneven teeth and the jitter in the circumferential direction.

[0012] In addition, a nut member 177 is required to be screwed on the threaded portion 174 of the shaft portion 173 protruding from the cylindrical portion 163. Therefore, there is a screw tightening operation during assembly, the operability is deteriorated, the number of parts is also large, and the part management is also poor.

Summary of the invention

[0013] The present invention was developed in view of the above-mentioned problems, and its purpose is to provide a method that can suppress shaking in the circumferential direction, and has excellent connection operability between the hub ring and the outer joint member of the constant velocity universal joint, and the hub ring and the like A wheel bearing device with excellent strength and stable fitting of outer joint components of a speed universal joint, and an axle module using the wheel bearing device.

[0014] The first wheel bearing device of the present invention has: a bearing having multiple rows of rolling elements arranged between the opposed outer ring and the inner ring; a hub ring mounted on the wheel; and a constant velocity universal joint , Wherein the shaft of the outer joint member of the constant velocity universal joint inserted in the hole of the hub wheel is integrated with the hub ring via a concave-convex fitting structure, and the outer diameter surface of the shaft of the outer joint member is integrated with the hub ring Any one of the inner diameter surfaces of the hole portion is provided with a convex portion extending in the axial direction, and the convex portion is pressed into the outer diameter surface of the shaft portion of the outer joint member and the inner diameter surface of the hole portion of the hub ring in the axial direction In the other one, a concave portion that is in close contact and fitting with the convex portion is formed on the other by the pressing, and the concave-convex fitting structure in which the entire area of the fitting contact portion of the convex portion and the concave portion is in close contact, the The hardness of at least the press-fitting start end of the convex part is higher than the hardness of the recessed part formation part which is the part which press-fits the said convex part, and this hardness difference is 20HRC or more.

[0015] According to the first wheel bearing device of the present invention, the concave-convex fitting structure is in close contact with the entire area of the fitting contact portion of the convex portion and the concave portion. Therefore, the fitting structure is not formed in the radial and circumferential directions. The swaying gap. Moreover, since the hardness difference between the pressing-in start end of the convex portion and the portion where the concave portion is formed is 20HRC (Rockwell C hardness) or more, the pressure applied when the convex portion is pressed into the other side (opposite side) The entry force (press-in load) can be relatively small. That is, it is not necessary to apply a large press-fitting load, so it is possible to prevent friction and damage (crushing) between the convex portion and the concave portion.

[0016] The hardness of the press-fitting start end of the convex portion is preferably 50 to 65 HRC, and the hardness of the concave portion formation portion is preferably 10 to 30 HRC.

[0017] The convex portion can be heat treated and hardened by high frequency heat treatment. Thereby, it is possible to stabilize the hardness difference between the convex portion side (the press-fitting start end portion of the convex portion) and the concave portion forming side (the concave portion forming portion), and the hardness can be formed to be 20HRC or more. Here, the so-called high-frequency heat treatment refers to quenching in which a portion necessary for quenching is keyed into a coil through which a high-frequency current flows, and Joule heat is generated by electromagnetic induction, and the principle of heating a conductive object is applied to quenching.

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[0018] The second wheel bearing device of the present invention has: a bearing having multiple rows of rolling elements arranged between the opposed outer ring and the inner ring; a hub ring mounted on the wheel; and a constant velocity universal joint , Wherein the shaft of the outer joint member of the constant velocity universal joint inserted in the hole of the hub wheel is integrated with the hub wheel via a concave-convex fitting structure, and the outer diameter surface of the shaft of the outer joint member is integrated with the hub wheel Any one of the inner diameter surfaces of the hole portion is provided with a convex portion extending in the axial direction, and the convex portion is pressed into the outer diameter surface of the shaft portion of the outer joint member and the inner diameter of the hole portion of the hub ring along the axial direction On the other of the surfaces, a concave portion that is in close contact with the convex portion is formed on the other by the pressing, and the concave-convex fitting structure in which the entire area of the fitting contact portion of the convex portion and the concave portion is in close contact is formed, In addition, a foreign matter intrusion prevention mechanism is provided to prevent foreign matter from intruding into the concave-convex fitting structure.

[0019] According to the second wheel bearing device of the present invention, in the same way as the first wheel bearing device, in the concave-convex fitting structure, the entire area of the fitting contact portion between the convex portion and the concave portion is in close contact with each other. , There is no gap that produces shaking in the radial and circumferential directions. Furthermore, by providing the foreign matter intrusion prevention mechanism, it is possible to prevent foreign matter from entering the concave-convex fitting structure.

[0020] The outer joint member has a mouth into which the inner joint member is housed, and the shaft portion protruding from the bottom of the mouth, and the foreign matter intrusion prevention mechanism is arranged between the end of the hub wheel and the bottom of the mouth. Between the sealing parts.

[0021] The foreign matter intrusion prevention mechanism is constituted by a seal interposed between the fitting contact portion of the convex portion and the concave portion in the concave-convex fitting structure. With this seal, it is possible to improve the adhesion of the fitting contact portions, and it is possible to prevent foreign matter from entering between the fitting contact portions.

[0022] On the outer side of the shaft portion of the outer joint member, there may be provided an engagement portion for stopping that engages with the inner diameter surface of the hole portion of the hub ring, and engages with the inner diameter surface of the hole portion of the hub ring. A seal that constitutes the foreign matter intrusion prevention mechanism is interposed between the parts.

[0023] The external side and the internal side of the concave-convex fitting structure may be provided with a foreign matter intrusion prevention mechanism.

[0024] The third wheel bearing device of the present invention has: a bearing having multiple rows of rolling elements arranged between the opposed outer ring and the inner ring; a hub ring mounted on the wheel; and a constant velocity universal joint , Wherein the shaft portion of the outer joint part of the constant velocity universal joint inserted in the hole of the hub ring is integrated with the hub ring via a concave-convex fitting structure, and the bearing has an outer part forming a plurality of rows of outer rings; forming The inner part of the inner ring of multiple rows, the inner ring of the outer side of the inner part is formed on the outer diameter surface of the hub ring, and the inner ring of the inner side of the inner part is formed on the hub ring On the outer diameter surface of the inner ring where the small-diameter stepped portion on the built-in side is fitted, the opening of the annular space formed between the outer member and the inner member is sealed by a sealing member, and the hub ring is subjected to tempering treatment , A hardened layer is provided on the surface corresponding to the small-diameter step part embedded in the inner ring from the sealing area on the outer side than the inner ring on the outer side to the inner ring on the outer side including the inner ring on the outer side. Either the outer diameter surface of the shaft portion of the joint member and the inner diameter surface of the hole portion of the hub ring is provided with a convex portion extending in the axial direction, and the convex portion is pressed into the shaft portion of the outer joint member in the axial direction. The other of the outer diameter surface and the inner diameter surface of the hole of the hub wheel is pressed into the other to form a concave portion that is in close contact with the convex portion to form a fitting contact portion between the convex portion and the concave portion The concave-convex fitting structure in close contact with the entire area.

[0025] According to the third wheel bearing device of the present invention, similar to the first and second wheel bearing devices, in the concave-convex fitting structure, the entire area of the fitting contact portion of the convex portion and the concave portion is in close contact with each other. In this fitting structure, there is no gap that generates rattling in the radial direction and the circumferential direction.

[0026] According to the third wheel bearing device of the present invention, since the hub wheel is quenched and tempered, it extends from the sealing area of the hub wheel to the small-diameter stepped portion including the inner ring on the outer side and embedded with the inner ring. A hardened layer is set on the corresponding surface, so

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In order to be able to achieve the improvement of the fatigue strength of the material. Here, the so-called tempering refers to the fineness of crystal particles, the adjustment of the material, the improvement of toughness, etc., and the use of thermal work such as quenching or annealing.

[0027] The surface hardness of the hardened layer can form HRC54~HRC64. Thereby, in the outer diameter surface of the hub wheel, not only the wear resistance from the inner side root joint of the wheel mounting flange to the inner side and the outer side raceway surface is improved, but also the mechanical strength can be sufficiently improved.

[0028] The hub ring can be integrally provided with a wheel mounting flange for mounting a wheel, and the surface hardness of the outer side root joint of the wheel mounting flange is set to 35HRC or less. In this way, if the surface hardness of the outer root joint portion of the wheel mounting flange is set to 35HRC or less, the workability such as cutting can be improved, and heat treatment deformation can be suppressed. In addition, the hub wheel can make the surface hardness of the bolt hole into which the hub bolt is pressed close to the surface hardness of the hub bolt.

[0029] The outer joint member preferably has a mouth in which the inner joint member is housed and the shaft portion protruding from the bottom of the mouth, wherein the mouth is formed in a non-contact shape with the hub wheel, and preferably the hub wheel The end of the built-in side is tightened, and preload is applied to the rolling bearing.

[0030] The inner end of the hub wheel is plastically deformed radially outward to form a fastening portion, and the inner ring is fixed in the axial direction by the fastening portion, so that the surface of the inner end of the hub ring can be made The hardness is set to 25HRC or less. Therefore, it is not necessary to firmly tighten the nut or the like to manage the preload amount as in the past.

8wt%Ofcarbon steel. [0031] The hub ring can be carbon-containing 0. 4wt%~0. 8wt% of carbon steel.

[0032] The convex portion of the concave-convex fitting structure can be provided on the shaft portion of the outer joint member. In this case, by pressing the shaft portion from the axial end of the convex portion into the hole of the hub ring, the convex portion can form a close fit with the convex portion on the inner diameter surface of the hole of the hub ring. The concave portion can constitute the concave-convex fitting structure. At this time, the convex portion bites into the concave portion forming surface of the other side (the inner diameter surface of the hole portion of the hub ring) to form a state in which the diameter of the hole portion is slightly enlarged, allowing the convex portion to move in the axial direction. If the axial movement stops, The hole is reduced in diameter to restore its original diameter. As a result, the entire fitting contact portion of the convex portion and the concave portion is in close contact with each other stably.

[0033] When the convex portion is provided on the shaft portion of the outer joint member, it is preferable to set the inner diameter dimension of the inner diameter surface of the hole portion of the hub wheel to be larger than the apex of the convex portion connecting the shaft portion of the outer joint member. The diameter of the circle is small and larger than the diameter of the circle connecting the bottoms between the convex parts.

[0034] In addition, the convex portion of the concave-convex fitting structure can be provided on the inner diameter surface of the hole of the hub wheel. In this case, by pressing the shaft portion from the axial end of the convex portion into the hole of the hub wheel, the convex portion can be used to form a convex portion on the outer diameter surface of the shaft portion of the outer joint member. The recessed portion that is closely fitted can constitute the aforementioned concave-convex fitting structure. At this time, the convex part bites into the outer diameter surface of the shaft part to form a state where the hole part of the hub wheel is slightly enlarged, allowing the convex part to move in the axial direction. If the axial movement stops, the hole part wants to return to the original The diameter is reduced. Thereby, the entire fitting contact portion of the convex portion and the concave portion (the outer diameter surface of the shaft) of the counterpart member fitted with the convex portion is in stable and close contact.

[0035] In the case where the convex portion is provided on the inner diameter surface of the hole portion of the hub wheel, it is preferable to set the outer diameter dimension of the shaft portion of the outer joint member to be larger than the apex of the plurality of convex portions connecting the hole portion of the hub wheel. The diameter of the arc is larger and smaller than the diameter of the circle connecting the bottoms between the convex parts.

[0036] Preferably, the convex portion is pressed into the other at least from the vertex to the middle portion in the protruding direction, and the circumferential thickness of the middle portion in the protruding direction is greater than that between the convex portions adjacent in the circumferential direction and corresponds to the middle portion The circumferential size of the position is small. With this setting, the sum of the circumferential thickness of the middle portion of the convex portion in the protruding direction is greater than the circumferential thickness of the convex portion on the opposite side between the convex portion adjacent to the circumferential direction at the position corresponding to the middle portion The sum is small.

[0037] A shaft portion anti-disengagement structure may be provided between the shaft portion of the outer joint member and the inner diameter surface of the hub wheel. By setting

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The shaft anti-disengagement structure can prevent the outer joint member of the constant velocity free joint from detaching from the hub wheel in the axial direction. The shaft anti-fall structure is preferably maintained in an unhardened state.

[0038] In the bolted state of the hub wheel and the shaft of the outer joint member, the end surface of the shaft of the outer joint member and the inner wall on which the bearing surface of the bolt member is placed can be provided in the hole of the hub ring. As a result, the bolt fixation is stable.

[0039] A seal may be interposed between the bearing surface and the inner wall of the bolt member for bolting the hub ring and the shaft portion of the outer joint member.

[0040] It is preferable to provide a recessed portion for accommodating an overflow portion formed by the press-fitted recessed portion. Here, the overflow portion refers to the amount of material of the volume of the concave portion into which the concave portion of the convex portion is fitted (fitted), is pressed out from the formed concave portion, is cut off to form the concave portion, or is pressed It is composed of both the output and the cut off. Therefore, when a convex portion is provided on the shaft portion of the outer joint member, the recess portion is provided on the shaft portion on the outer side of the concave-convex fitting structure, and when the convex portion is provided on the inner diameter surface of the hole portion of the hub ring , It is provided on the inner diameter side of the hole of the hub on the built-in side of the concave-convex fitting structure.

[0041] Preferably, in the shaft portion of the outer joint member, the recessed portion is provided on the outer side of the convex portion, and a shaft extension for alignment with the hole portion of the hub ring is provided on the outer side of the recessed portion unit.

[0042] Preferably, the concave-convex fitting structure is arranged at an avoiding position just below the raceway surface of the rolling bearing. That is, if the shaft is pressed into the hole of the hub wheel, the hub wheel expands. This expansion generates hoop stress on the raceway surface of the rolling bearing. Here, the hoop stress refers to the force to expand the diameter in the outer diameter direction. Therefore, when hoop stress is generated on the bearing raceway surface, it will cause the reduction of rolling fatigue life and the generation of cracks. Therefore, by arranging the concave-convex fitting structure at the avoiding position just below the raceway surface of the rolling bearing, the generation of hoop stress on the raceway surface of the bearing can be suppressed to a minimum.

[0043] The axle module of the present invention has: a wheel bearing device having a constant velocity universal joint on the external side; a drive shaft connected to the constant velocity universal joint of the wheel bearing device at one end; and the drive shaft The inner side constant velocity universal joint connected at the other end, wherein the wheel bearing device has: a bearing having multiple rows of rolling elements arranged between the opposed outer ring and the inner ring; and a hub mounted on the wheel Ring; the outer side of the constant velocity universal joint, the outer side of the constant velocity universal joint on the outer side of the outer joint member of the shaft portion of the outer diameter surface and the inner diameter surface of the hub ring hole is provided A convex portion extending in the axial direction presses the convex portion into the other of the outer diameter surface of the shaft portion of the outer joint member and the inner diameter surface of the hole portion of the hub ring along the axial direction, and is formed by the press-fitting The other is formed with a concave portion in close contact with the convex portion, the concave-convex fitting structure in which the entire area of the fitting contact portion of the convex portion and the concave portion is in close contact, and the outer member of the bearing having the outer ring and The steering knuckle on the vehicle body side is fitted, and the maximum outer diameter of the constant velocity universal joint on the external side and the constant velocity universal joint on the internal side is smaller than the outer diameter of the knuckle fitting surface of the outer member.

[0044] According to the axle module of the present invention, in the bearing device for a wheel, in the concave-convex fitting structure, the entire area of the fitting contact portion of the convex portion and the concave portion is in close contact with each other. Therefore, in the fitting structure, the radial and circumferential directions There is no gap to produce shaking.

[0045] The maximum outer diameter of the constant velocity free joint on the external side and the constant velocity free joint on the internal side can be formed to be smaller than the outer diameter of the knuckle fitting surface of the outer member, so the axle can be easily made The module passes through the steering knuckle.

[0046] In the axle module of the present invention, it is preferable to use the wheel bearing device described in any one of the above-mentioned wheel bearing devices.

[0047] [Effects of the Invention]

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[0048] In the present invention, in the concave-convex fitting structure, since there is no gap that generates rattling in the radial and circumferential directions, the entire fitting portion contributes to the transmission of rotational torque, enabling stable torque transmission, and also Will not produce noise. In addition, since there is no gap in close contact, the strength of the torque transmission portion is improved. Therefore, the wheel bearing device can be made light and compact.

[0049] By pressing the convex portion provided on either the outer diameter surface of the shaft portion of the outer joint member and the inner diameter surface of the hole portion of the hub ring into the other in the axial direction, it is possible to form a The convex part is in close contact with the concave part to be fitted. Therefore, the concave-convex fitting structure can be reliably formed. Moreover, there is no need to form splines on the parts forming the recesses, and the productivity is excellent, and there is no need to match the splines to each other in phase, so assemblability can be improved, and damage to the tooth surface during press-fitting can be avoided. Stable mating state.

[0050] Since the hardness difference between the press-fitting start end of the convex portion and the concave portion forming part is 20HRC or more, when the convex portion is press-fitted to the other side, only a small press-fitting force (press-fitting load) can be applied. The press-fitting can improve press-fitting properties. In addition, since a large press-fitting load can not be applied, it is possible to prevent abrasion or damage (cracking) of the convex portion and the concave portion, and it is possible to stably constitute a concave-convex fitting structure that does not rattle in the radial and circumferential directions.

[0051] If the hardness of the press-fitting start end of the convex portion is 50 to 65 HRC, a more stable concave-convex fitting structure can be constructed. In addition, if the hardness of the recessed portion formation portion is 10 to 30 HRC, the recessed portion forming side can be softer and the pressability can be improved. [0052] The convex portion can be heat-treated and hardened by high-frequency heat treatment. If the convex portions are hardened by high frequency heat treatment, there are advantages described below. (A) It can be heated locally, and it is easy to adjust the quenching conditions. (B) Since it can be heated in a short time, there is little oxidation. (C) Compared with other quenching methods, there is no quenching warpage. (D) The surface hardness is high, and excellent abrasion resistance can be obtained. (E) The selection of the depth of the hardened layer is also relatively easy. (F) It is easy to automate and can also be assembled on a mechanical production line.

[0053] By providing a foreign matter intrusion prevention mechanism, it is possible to prevent foreign matter from intruding into the concave-convex fitting structure. That is, by preventing the intrusion of rainwater or foreign matter by the foreign matter intrusion prevention mechanism, it is possible to prevent rainwater or foreign matter from entering the concave-convex fitting structure and deteriorating adhesion.

[0054] In a structure in which a sealing member is arranged between the end of the hub ring and the bottom of the mouth, the gap between the end of the hub and the bottom of the mouth is blocked by the sealing member, thereby preventing rainwater or foreign matter from getting This gap intrudes into the concave-convex fitting structure. As the sealing member, as long as it can be interposed between the end of the hub wheel and the bottom of the mouth, for example, an existing (commercially available) O-ring or the like can be used, and the foreign matter intrusion prevention mechanism can be constructed at low cost. In addition, the commercially available O-rings and the like are available in various materials and sizes, and do not need to be specially manufactured, and can constitute a foreign matter prevention mechanism that reliably performs a sealing function.

[0055] In the structure in which the sealing material is interposed between the fitting contact portions of the convex portion and the concave portion, the intrusion of foreign matter between the fitting contact portions can be prevented, and the reliability of preventing the foreign matter from entering can be improved. In addition, in the case of interposing the sealing material, it is only necessary to apply the sealing material to the surface of the convex portion before press-fitting.

[0056] As long as the outer joint member is provided with an engagement portion for stopping that engages with the inner diameter surface of the hole portion of the hub ring on the outer side of the shaft portion, the engagement portion is interposed between the inner diameter surface of the hub ring and the engagement portion. By installing the seal, it is possible to prevent foreign matter from intruding from the external side.

[0057] As long as the external side and internal side of the concave-convex fitting structure are provided with foreign matter intrusion prevention mechanisms, it is possible to prevent foreign substances from intruding into the concave-convex fitting structure from the external side and the internal side. Therefore, it is possible to more stably avoid deterioration of adhesiveness over a long period of time. [0058] In a structure in which the hub wheel is tempered and a hardened layer is provided from the sealing area to the surface corresponding to the small-diameter step portion, the fatigue strength of the material can be improved, so it is possible to achieve small size, light weight, and make Wheel hub

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Strength and durability are improved. In addition, the surface vibration that is the cause of brake chattering is not deteriorated, and the fixing strength of the hub bolt can be ensured.

[0059] When the surface hardness of the hardened layer is formed to be 54HRC to 64HRC, sufficient mechanical strength can be increased, and the strength and durability of the hub wheel can be further improved.

[0060] In the case where the surface hardness of the outer side root joint of the wheel mounting flange is 35HRC or less, it is possible to prevent deterioration of the surface vibration accuracy of the brake disc mounting surface of the wheel mounting flange due to heat treatment deformation. In addition, since the surface hardness of the bolt hole can be made close to the surface hardness of the hub bolt, it is possible to prevent the serration of the hub bolt from collapsing and reducing the fixing force.

[0061] When the surface hardness of the inner-side end portion of the hub wheel is set to 25HRC or less, the fastening portion can be formed by the hub wheel end portion. Thereby, it is not necessary to tighten the nut or the like to manage the preload amount, so the assemblability to the vehicle can be simplified and the preload amount can be maintained for a long period of time. In addition, it does not reduce the workability, and also does not cause micro cracks on the surface due to plastic processing, which can further improve its reliability in terms of quality.

[0062] In the structure in which the mouth of the outer joint member is in a non-contact state with the hub ring, it is possible to prevent the occurrence of noise caused by the contact between the mouth and the hub ring. In addition, in the structure in which the end of the hub ring is fastened and the bearing is preloaded, the shaft of the outer joint member can be pressed into the shaft of the outer joint member regardless of the preloading of the outer joint member, so that the hub ring and the outer joint member can be pressed together. Improved connectivity (assembly). Furthermore, it is not necessary to firmly tighten the nut or the like to manage the preload amount, so the assembly to the wheel can be simplified and the preload amount can be maintained for a long period of time.

[0063] When the surface hardness of the inner end of the hub wheel is set to 25HRC or less, the workability will not be reduced, and there will be no micro-cracks on the surface due to plastic working, and the quality can be further improved. Its reliability.

[0064] In the case of using medium carbon steel with a carbon content of 0.40wt%~0.80wt% for the wheel hub, it is advantageous from the perspective of ease of forging, machinability, heat treatment, or economy, and is particularly suitable For high-frequency quenching, etc.

[0065] In addition, when the convex portion of the concave-convex fitting structure is provided on the shaft portion of the outer joint member, the hardness on the shaft portion side can be increased, and the rigidity of the shaft portion can be increased. In addition, when the convex part of the concave-convex fitting structure is provided on the inner diameter surface of the hole part of the hub wheel, the hardness treatment (heat treatment) on the shaft part side is not necessary, so the productivity of the outer joint part of the constant velocity free joint superior.

[0066] By making the circumferential thickness of the middle portion of the convex portion in the protruding direction smaller than the size at the position corresponding to the middle portion between the convex portions adjacent in the circumferential direction, it is possible to increase the circumference between the concave portions adjacent in the circumferential direction. To thickness. Therefore, the shearing area between the recesses adjacent in the circumferential direction can be increased, and the twist strength can be ensured. In addition, since the tooth thickness (circumferential thickness) of the convex portion on the side with high hardness is small, the press-fitting load can be reduced, and the press-fitting can be improved.

[0067] With the shaft portion anti-disengagement structure, the shaft portion of the outer joint member can be effectively prevented from being separated from the hole portion of the hub wheel in the axial direction. As a result, a stable connection state can be maintained, and the quality of the wheel bearing device can be improved. In particular, if the shaft anti-fall structure is in an unhardened state, the shaft anti-fall structure is soft, and the workability can be improved.

[0068] In the structure that allows the separation of the concave-convex fitting structure, by applying an axial tensile force to the shaft portion of the outer joint member, the outer joint member can be detached from the hole of the hub wheel, so that the repair and Improvement of inspection operability (maintenance).

[0069] By fixing the bolts to restrict the axial separation of the shaft portion from the hub wheel, stable torque transmission can be performed for a long period of time. In particular, by providing the inner wall of the bearing surface constituting the head of the bolt member on the outside of the hub ring, the bolt is fixed stably and can also function as a positioning. The dimensional accuracy of the wheel bearing device is stable, and the along

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The axial length of the concave-convex fitting structure arranged in the axial direction is ensured at a stable length, and the torque transmission can be improved. [0070] By interposing a seal between the bearing surface of the bolt member and the inner wall, it is possible to prevent rainwater or sundries from entering the bolt member side, and it is possible to prevent rainwater or sundries from entering the concave-convex fitting structure and deteriorating adhesion .

[0071] By providing a storage portion (pit portion) for accommodating the overflow portion generated by the depression formed by the press-fit, the overflow portion can be held (maintained) in the storage portion, and the overflow portion does not enter the vehicle outside the device, etc. . That is, the overflow portion can be stored in the storage portion in advance without any change, and there is no need to remove the overflow portion, the assembly work man-hours can be reduced, the assembly workability can be improved, and the cost can be reduced.

[0072] In addition, by providing the shaft extension portion for alignment, the overflow portion in the recess portion does not fly out to the shaft extension portion side, and the accommodation of the overflow portion is more stable. Moreover, since the shaft overflow portion is used for centering, eccentricity can be prevented and the shaft portion can be pressed into the hub wheel. Therefore, the outer joint member and the hub wheel can be connected with high precision, and stable torque transmission can be performed.

[0073] By arranging the concave-convex fitting structure at an avoiding position just below the raceway surface of the rolling bearing, the generation of hoop stress on the raceway surface of the bearing is suppressed to a minimum. As a result, it is possible to prevent bearing defects such as reduction in rolling fatigue life, generation of cracks, and stress corrosion cracking, and it is possible to provide a high-quality bearing.

[0074] In the axle module of the present invention, since there is no gap in the concave-convex fitting structure that produces rattling in the radial and circumferential directions, the entire fitting portion contributes to the transmission of the rotational torque and enables stable torque. Pass, and it will not produce noise. In addition, due to the close contact without gaps, the strength of the torque transmission portion is improved. Therefore, the wheel bearing device can be made light and compact.

[0075] In the axle module of the present invention, it is possible to easily pass through the steering knuckle. Therefore, it is possible to reduce the work man-hours at the assembly work site, and it is possible to improve the operability. In this case, it is not necessary to rotate the knuckle as in the past, so the working space can be minimized. In addition, it is possible to prevent damage to parts during disassembly, assembly, etc., and to stabilize the quality.

Description of the drawings

[0076] FIG. 1 is a longitudinal cross-sectional view showing a wheel bearing device according to a first embodiment of the present invention.

[0077] FIG. 2A is an enlarged cross-sectional view of the concave-convex fitting structure of the bearing device for the wheel.

[0078] FIG. 2B is an enlarged view of part X of the above-mentioned FIG. 2A.

[0079] FIG. 3 is a cross-sectional view showing the wheel bearing device before assembly.

4 is a cross-sectional view showing the method of assembling the bearing device for the wheel.

[0081] FIG. 5 is a cross-sectional view showing an assembling method of the wheel bearing device.

[0082] FIG. 6 is an enlarged cross-sectional view of a main part of the concave-convex fitting structure of the bearing device for the wheel.

[0083] FIG. 7A is an enlarged cross-sectional view showing a sealing member that seals the gap between the mouth portion of the outer ring of the wheel bearing device and the fastening portion of the hub ring, when an O-ring is used.

[0084] FIG. 7B is an enlarged cross-sectional view showing the sealing member that seals the gap between the mouth portion of the outer ring of the wheel bearing device and the fastening portion of the hub ring when a gasket is used.

[0085] FIG. 8 is a longitudinal cross-sectional view showing a bearing device for a wheel according to a second embodiment of the present invention.

[0086] FIG. 9 is a cross-sectional view showing an assembling method of the wheel bearing device of FIG. 8 described above.

[0087] FIG. 10 is a cross-sectional view showing an assembling method of the wheel bearing device of FIG. 8 described above.

[0088] FIG. 11 is a longitudinal cross-sectional view showing a bearing device for a wheel according to a third embodiment of the present invention.

[0089] FIG. 12 is a longitudinal cross-sectional view of the wheel bearing device of FIG. 11 described above.

CN 101802425 Β

[0090] FIG. 13 is a longitudinal cross-sectional view of the wheel bearing device of FIG. 11 described above.

[0091] FIG. 14A is an end view showing the end surface of the shaft portion of the outer ring of the wheel bearing device of FIG.

[0092] FIG. 14B is an end view showing the end surface of the shaft portion of the outer ring of the wheel bearing device of FIG. 11, which is arranged at a predetermined pitch in the circumferential direction.

15 is a longitudinal cross-sectional view showing a bearing device for a wheel according to a fourth embodiment of the present invention.

[0094] FIG. 16 is an enlarged cross-sectional view of a main part of the wheel bearing device of FIG. 15 described above.

[0095] FIG. 17 is a cross-sectional view showing the outer joint member before assembly of the wheel bearing device of FIG. 15 described above.

[0096] FIG. 18 is a cross-sectional view of a main part of a bearing device for a wheel showing a fifth embodiment of the present invention.

[0097] FIG. 19 is a cross-sectional view of a main part of a wheel bearing device according to a sixth embodiment of the present invention.

[0098] FIG. 20 is a cross-sectional view of a main part of a bearing device for a wheel showing a seventh embodiment of the present invention.

[0099] FIG. 21 is a cross-sectional view showing a wheel bearing device according to an eighth embodiment of the present invention.

[0100] FIG. 22 is an enlarged cross-sectional view of a main part of the wheel bearing device of FIG. 21 described above.

[0101] FIG. 23 is a cross-sectional view showing a wheel bearing device according to a ninth embodiment of the present invention.

[0102] FIG. 24 is a cross-sectional view showing the aforementioned wheel bearing device of FIG. 23 before assembling.

[0103] FIG. 25 is an enlarged cross-sectional view of a main part of the wheel bearing device of FIG. 23 described above.

[0104] FIG. 26 is a cross-sectional view showing a method of separating the concave-convex fitting structure of the wheel bearing device of FIG. 23 described above.

[0105] FIG. 27 is a cross-sectional view showing a method of repressing the wheel bearing device of FIG. 23 described above.

[0106] FIG. 28A is an enlarged cross-sectional view of a first modification of the concave-convex fitting structure.

[0107] FIG. 28B is an enlarged cross-sectional view of a second modification of the concave-convex fitting structure.

[0108] FIG. 29A is a cross-sectional view showing a wheel bearing device according to a ninth embodiment of the present invention.

[0109] FIG. 29B is an enlarged view of part Y of FIG. 29A described above.

[0110] FIG. 30 is an enlarged cross-sectional view of a main part of the concave-convex fitting structure of the wheel bearing device of FIG. 29A.

[0111] FIG. 31 is a longitudinal sectional view of the axle module of the present invention.

[0112] FIG. 32 is an assembly process diagram of the axle module to a vehicle.

[0113] FIG. 33 is an assembly process diagram of the axle module to a vehicle.

[0114] FIG. 34 is an assembly process diagram of the axle module to a vehicle.

35 is a cross-sectional view showing a bearing device for a wheel according to a tenth embodiment of the present invention.

[0116] FIG. 36 is a graph showing changes in press-fitting load.

[0117] FIG. 37 is a cross-sectional view of a conventional wheel bearing device.

[0118] Attached to the description of the icon number

<td>[0119]</td><td>1</td><td>Hub ring</td>

<td>[0120]</td><td>2</td><td>Bearing</td>

<td>[0121]</td><td>3</td><td>Constant velocity universal joint</td>

<td>[0122]</td><td>11</td><td>mouth</td>

<td>[0123]</td><td>11a</td><td>back</td>

<td>[0124]</td><td>12</td><td>Shaft</td>

<td>[0125]</td><td>22</td><td>Hole</td>

<td>[0126]</td><td>22g</td><td>Inner wall</td>

CN 101802425 Β

<td>[0127]</td><td>23</td><td>Footpath step</td>

<td>[0128]</td><td>24</td><td>Inner circle</td>

<td>[0129]</td><td>26</td><td>Outer raceway surface (outer ring)</td>

<td>[0130]</td><td>27</td><td>Outer raceway surface (outer ring)</td>

<td>[0131]</td><td>28</td><td>Inside raceway surface (inner ring)</td>

<td>[0132]</td><td>29</td><td>Inside raceway surface (inner ring)</td>

<td>[0133]</td><td>30</td><td>Rolling element</td>

<td>[0134]</td><td>31</td><td>Fastening part (addition part)</td>

<td>[0135]</td><td>35</td><td>Convex</td>

<td>[0136]</td><td>36</td><td>Recess</td>

<td>[0137]</td><td>37</td><td>Inner surface</td>

<td>[0138]</td><td>38</td><td>Mating contact site</td>

<td>[0139]</td><td>45</td><td>Overflow</td>

<td>[0140]</td><td>50</td><td>Pit</td>

<td>[0141]</td><td>51</td><td>Circumferential groove</td>

<td>[0142]</td><td>52</td><td>Handcuffs Department (Earth Department)</td>

<td>[0143]</td><td>90</td><td>Threaded hole</td>

<td>[0144]</td><td>94</td><td>Bolt parts</td>

<td>[0145]</td><td>94a</td><td>Head part</td>

<td>[0146]</td><td>98</td><td>gap</td>

<td>[0147]</td><td colspan="2">100a bearing surface</td>

<td>[0148]</td><td>Μ</td><td>Concave-convex fitting structure</td>

<td>[0149]</td><td>Ml</td><td>Shaft stop structure</td>

<td>[0150]</td><td>Hl</td><td>Hardened layer</td>

<td>[0151]</td><td>ΤΙ</td><td>External side constant velocity universal joint</td>

<td>[0152]</td><td>T2</td><td>Built-in side constant velocity universal joint</td>

<td>[0153]</td><td>W</td><td>Prevent foreign bodies from entering the organization</td>

<td>[0154]</td><td>W1</td><td>Prevent foreign bodies from entering the organization</td>

<td>[0155]</td><td>W2</td><td>Prevent foreign bodies from entering the organization</td>

<td>[0156]</td><td>W3</td><td>Prevent foreign bodies from entering the organization</td>

Detailed ways

[0157] The following describes embodiments of the present invention based on FIGS. 1 to 35. FIG. 1 shows a wheel bearing device according to the first embodiment. The wheel bearing device integrates a hub ring 1, a multi-row rolling bearing 2 and a constant velocity universal joint 3. As shown in FIG.

[0158] The constant velocity universal joint 3 is composed of main components: an outer ring 5 as an outer joint member; an inner ring 6 as an inner joint member arranged on the inner side of the outer ring 5; interposed between the outer ring 5 and the inner ring A plurality of balls 7 transmitting torque between 6; a cage 8 that is interposed between the outer ring 5 and the inner ring 6 to hold the balls 7. The end portion 10a of the shaft 10 is press-fitted into the inner diameter 6a of the hole portion of the inner ring 6 and spline-fitted therewith, thereby being coupled to the shaft 10 so as to be able to transmit torque. In addition, a retaining ring 9 for preventing the shaft from coming off is attached to the end 10a of the shaft 10.

CN 101802425 Β

[0159] The outer ring 5 is composed of a mouth portion 11 and a rod portion (shaft portion) 12. The mouth portion 11 has a bowl shape with one end open, and the inner spherical surface 13 is formed with a plurality of portions extending in the axial direction at equal intervals in the circumferential direction. A track slot 14. The track groove 14 extends to the open end of the mouth 11. In the inner ring 6, a plurality of track grooves 16 extending in the axial direction are formed on the outer spherical surface 15 at equal intervals in the circumferential direction.

[0160] The track grooves 14 of the outer ring 5 and the track grooves 16 of the inner ring 6 are paired with each other, and a ball as a torque transmission element is mounted on the ball track formed by each pair of track grooves 14, 16 so as to be rollable. 7. The balls 7 are interposed between the track groove 14 of the outer ring 5 and the track groove 16 of the inner ring 6 to transmit torque. The cage 8 is slidably interposed between the outer ring 5 and the inner ring 6, and is in contact with the inner spherical surface 13 of the outer ring 5 via the outer spherical surface 8a, and is in contact with the outer spherical surface 15 of the inner ring 6 via the inner spherical surface 8b. In addition, the constant velocity universal joint in this case shows a non-undercut type with a straight portion at the bottom of the track groove, but it can also be a ball cage (less labor and eight) and other constant velocity universal joints. Connector.

[0161] In addition, the opening of the mouth 11 is closed by the shield 60. The shield 60 is composed of a large-diameter portion 60a, a small-diameter portion 60b, and a bellows belly 60c connecting the large-diameter portion 60a and the small-diameter portion 60b. The large-diameter portion 60a is externally fitted to the opening of the mouth portion 11, and is connected by the shield band 61 in this state, and the small-diameter portion 60b is externally fitted on the shield attachment portion 10b of the shaft 10, and in this state, the shield band 62 joint.

[0162] The hub wheel 1 has a cylindrical portion 20 and a flange 21 provided on an end portion of the cylindrical portion 20 on the outer side. The hole portion 22 of the cylindrical portion 20 has a shaft fitting hole 22a at the axial middle portion, a tapered hole 22b on the outer side, and a large-diameter hole 22c on the inner side. That is, in the shaft fitting hole 22a, the shaft 12 of the outer ring 5 of the constant velocity universal joint 3 and the hub wheel 1 are coupled via a concave-convex fitting structure M described later. In addition, a tapered portion (tapered hole) 22d is provided between the shaft portion fitting hole 22a and the large diameter hole 22c. The tapered portion 22d is reduced in diameter along the press-fitting direction when the hub wheel 1 and the shaft portion 12 of the outer ring 5 are joined. The taper angle θ of the tapered portion 22d (refer to FIG. 3) is, for example, 15° to 75°.

[0163] The rolling bearing 2 has the inner part of the inner ring 24 fitted on the small-diameter step part 23 provided on the joint side of the cylindrical part 20 of the hub ring 1, and the inner part of the inner ring 24 that spans the cylindrical part 20 of the hub ring 1 and even the inner ring 24. Outer part 25. The outer part 25 is provided with two rows of outer raceway surfaces (outer ring) 26.27 on its inner circumference, a first outer raceway surface 26 and a first inner raceway surface (inner ring) 28 provided on the outer circumference of the shaft portion of the hub ring 1 Opposing each other, the second outer raceway surface 27 and the second inner raceway surface (inner ring) 29 provided on the outer peripheral surface of the inner ring 24 are opposed to each other, and balls as rolling elements 30 are interposed therebetween. That is, a part of the hub wheel 1 (the outer diameter surface of the cylindrical portion 20) and the inner ring 24 press-fitted into the outer periphery of the inner side end of the hub wheel 1 constitute an inner member having inner rings 28 and 29. In addition, sealing members S1 and S2 are attached to both openings of the outer member 25.

[0164] In this case, the end portion of the inner side of the hub wheel 1 is tightened, and the bearing 2 is preloaded by the tightening portion 31. As a result, the inner ring 24 can be coupled to the hub ring 1. In addition, a bolt attaching hole 32 is provided on the flange 21 of the hub wheel 1, and a hub bolt 33 for fixing the wheel and the brake disc on the flange 21 is attached to the bolt attaching hole 32.

[0165] Generally, the hub ring 1 is hot-forged with medium carbon steel such as S53C (for example, steel with a carbon content of 0.4 to 0.8 wt%), then turned into a desired shape and size, and then subjected to induction hardening at necessary locations Wait to form a hardened layer. On the other hand, since it is possible to reduce the weight of the hub ring 1 while simultaneously improving the strength and durability of the hub ring under rotational bending conditions, there are cases where the hot-forged hub ring is subjected to a tempering treatment.

[0166] In the quenching and tempering treatment of the hub ring 1, quenching is performed after forging, and annealing is performed at a relatively high temperature of 400° C. or more to form a troostite or sorbite structure. Through this quenching and tempering treatment, the structure is granulated, the mechanical properties such as stretching, bending, and impact value are improved, and the ductility and flexibility are improved. By increasing the surface hardness, the mechanical strength is improved, but here, the surface hardness after the tempering treatment is set to 35HRC or less. When the surface hardness is set to more than 35HRC, the workability of cutting etc. will decrease, and the hot

CN 101802425 Β

The processing deformation becomes larger, the surface vibration accuracy of the brake disc mounting surface (outer-side end surface) of the wheel mounting flange 21 is deteriorated, and the indentability of the hub bolt 33 is reduced by increasing the hardness.

[0167] In addition, as shown in FIG. 3, in the outer diameter surface of the hub ring 1, from the sealing area, including the inner raceway surface 28 on the outer side, to the small-diameter stepped portion externally fitted with the inner ring 24 The surface corresponding to 23 (shown by the grid section line in the figure) is provided with a hardened layer H1. That is, from the outer diameter surface of the hub ring 1 that is in sliding contact with the sealing lip of the seal member S1 attached to the outer end of the rolling bearing 2, to the raceway surface 28 and the inner ring fitting surface of the hub ring 1. A hardened layer Η1 is provided on the position of The surface hardness of the hardened layer H1 is in the range of 54 to 64 HRC.

[0168] When the fastening portion 31 is formed, when the surface hardness of the inner end portion of the hub ring 1 exceeds 35 HRC, not only the workability will be reduced, but also micro cracks will occur on the surface due to plastic processing, which is reliable in terms of quality. Sexual decrease. In terms of plastic working, it is preferable to have a low surface hardness. In the inner side end of the hub wheel 1, the surface hardness is set to 25HRC or less by high-frequency annealing to improve reliability. In addition, compared with the conventional unheated portion after forging, micro cracks do not appear on the surface due to plastic working, and the reliability is further improved in terms of quality.

[0169] As shown in FIG. 2, the concave-convex fitting structure M is composed of, for example, a convex portion 35 provided on the end of the shaft portion 12 and extending in the axial direction and the inner diameter surface of the hole portion 22 formed in the hub wheel 1 (in this case Next, the recessed portion 36 on the inner diameter surface 37) of the shaft fitting hole 22a is configured, and the convex portion 35 is in close contact with the entire area of the fitting contact portion 38 of the concave portion 36 of the hub wheel 1 to which the convex portion 35 is fitted. That is, on the outer peripheral surface of the shaft portion 12 opposite to the mouth portion, a plurality of convex portions 35 are arranged at a predetermined pitch along the circumferential direction, and on the inner diameter surface 37 of the shaft portion fitting hole 22a of the hole portion 22 of the hub wheel 1. A plurality of concave portions into which the convex portion 35 fits is formed along the circumferential direction

36. That is, the convex portion 35 and the concave portion 36 fitted therewith are closely fitted over the entire circumference in the circumferential direction.

[0170] In this case, as shown in FIG. 2(a), each convex portion 35 has a triangular shape (mountain shape) with a convex R-shaped top in its cross section, and the fitting contact portion 38 is shown in FIG. 2(b). The range A shown is the range from the midsection of the mountain to the top of the mountain in the section. In addition, between the convex portions 35 adjacent in the circumferential direction, a gap 40 is formed on the inner diameter side of the inner diameter surface 37 of the hub wheel 1.

[0171] In this way, the hub wheel 1 and the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 can be connected via the concave-convex fitting structure M. At this time, as described above, the end portion of the inner side of the hub wheel 1 is fastened, and the bearing 2 is preloaded by the fastening portion 31, so there is no need to give the inner ring 24 through the mouth 11 of the outer ring 5. The pre-compression creates a non-contact state in which the mouth portion 11 does not contact the end portion of the hub wheel 1 (in this case, the fastening portion 31).

[0172] In addition, between the end portion of the shaft portion 12 of the outer ring 5 and the inner diameter surface 37 of the hub wheel 1, a shaft portion stopper structure M1 is provided. The shaft portion anti-disengagement structure M1 extends from the end portion of the shaft portion 12 of the outer ring 5 to the outward side (the side that constitutes the outer side of the vehicle when mounted on the vehicle), and is locked (clamped) with the tapered hole 22b The engaging portion (taper-shaped locking piece) 65 is formed. That is, the tapered locking piece 65 is composed of a ring-shaped body whose diameter expands from the inner side (the side constituting the inner side of the vehicle when mounted on the vehicle) toward the outer side, and at least a part of its outer peripheral surface 65a is crimped even Contact tapered hole 22bο

[0173] The wheel bearing device is provided with a foreign matter intrusion prevention mechanism Wo that prevents foreign matter from entering the concave-convex fitting structure M. In this case, they are provided on the built-in side of the concave-convex fitting structure M and the concave-convex fitting structure. The external side of Μ. That is, as shown in FIGS. 7A and 7B, a gap 98 is provided between the fastening portion 31 of the hub wheel 1 and the back surface 11a of the mouth portion 11, and a sealing member 99 embedded in the gap 98 can form a built-in side In this case, the foreign matter intrusion prevention mechanism Wk has a gap 98 formed from between the fastening portion 31 of the hub wheel 1 and the back surface 11a of the mouth portion 11 to between the large-diameter hole 22c and the shaft portion 12. In this embodiment, the sealing member 99 is arranged at the corners of the fastening portion 31 of the hub wheel 1 and the large-diameter hole 22c. In addition, as the sealing member 99, a member such as an O-ring as shown in FIG. 7A, or a member such as a gasket as shown in FIG. 7B may be used. In addition, the fastening portion 31 and the back surface 11a of the mouth portion 11 may be brought into abutment (contact). In this case, the contact surface pressure is 100 MPa or less.

CN 101802425 Β

[0174] The foreign matter intrusion prevention mechanism W2 on the external side can be configured by a tapered locking piece 65 as an engaging portion and a seal (not shown) interposed between the inner diameter surface of the tapered hole 22b. In this case, the tapered locking piece 65 is coated with a sealing material. That is, it is possible to apply a sealing material (sealant) made of various resins that can exhibit the sealability between the tapered locking piece 65 and the inner diameter surface of the tapered hole 22b when cured after application. In addition, as the seal, a material that does not deteriorate in the atmosphere in which the wheel bearing device is used is selected.

[0175] In addition, a seal may be interposed between the fitting contact portion 38 of the convex portion 35 and the concave portion 36 to thereby constitute the foreign matter intrusion prevention mechanism W (W3). In this case, a sealing material (sealant) made of various resins that can be cured after being applied to the surface of the convex portion 35 to exhibit the sealing properties between the fitting contact portions 38 may be used.

[0176] Next, a method of fitting the concave-convex fitting structure M will be described. In this case, as shown in FIG. 3, a thermosetting treatment is performed on the outer diameter portion of the shaft portion 12, and a spline composed of a convex portion 41a and a concave portion 41b along the axial direction is formed on the hardened layer H.

41. Therefore, the convex portion 41a of the spline 41 is hardened, and the convex portion 41a constitutes the convex portion 35 of the concave-convex fitting structure M. In addition, the range of the hardened layer H of this embodiment is from the outer edge of the spline 41 to a part of the bottom wall of the mouth 11 of the outer ring 5 as shown by the mesh section. As this thermal hardening treatment, various heat treatments such as induction hardening or carburizing and quenching can be adopted. Here, induction hardening refers to the method of applying the principle of adding the parts necessary for hardening to the coil where high-frequency current flows, generating Joule heat through electromagnetic induction, and heating conductive objects. In addition, carburizing and quenching refers to a method in which carbon is invaded and/or diffused from the surface of a low-carbon material, and then quenched. 5Little teeth. The modulus of the spline 41 of the shaft portion 12 (non-sound work) is 0.5 or less small teeth.

[0177] In addition, a hardened layer H1 formed by induction hardening is formed on the outer diameter side of the hub ring 1, and the inner diameter side of the hub ring is in an unsintered state. The range of the hardened layer H1 in this embodiment, as shown by the meshed section, is from the root portion (sub-treatment root portion) of the flange 21 to the vicinity of the fastening portion of the small-diameter step portion 23 into which the inner ring 24 is fitted . If induction hardening is performed, the surface is hardened, the hardness of the raw material is maintained inside, and the inner diameter side of the hub ring 1 can be maintained in an unsintered state. Therefore, on the inner diameter surface 37 side of the hole portion 22 of the hub wheel 1, an unhardened portion (unsintered state) that is not thermally hardened is formed.

[0178] The difference in hardness between the hardened layer H of the shaft portion 12 of the outer ring 5 and the unhardened portion of the hub wheel 1 is HRC 20 points or more. Specifically, it is preferable that the hardness of the hardened layer H is about 50 to 65 HRC, and the hardness of the side where the recess is formed (the inner diameter surface 37 of the shaft fitting hole 22a of the hole 22 of the hub wheel 1) is about 10 to 30 HRC. In addition, this difference in hardness is as described later, in order to make it easier for the convex portion 35 of the shaft 12 to be pressed into the hub ring 1 as the recessed portion formation portion when the shaft portion 12 of the outer ring 5 is fitted into the hole portion 22 of the hub ring 1. The inner diameter surface of the hole 22. Therefore, it is possible to harden only the press-fitting start end of the convex portion 35 (the end on the outer side). That is, at least the difference in hardness between the press-fitting start end of the convex portion 35 and the concave portion formation portion may be 20 HRC or more. Therefore, the press-fitting start end of the convex portion 35 can be set to about 50 to 65 HRC, and the inner diameter surface of the hole portion 22 of the hub wheel 1 as the recessed portion formation site has a hardness of about 10 to 30 HRC.

[0179] At this time, the middle portion of the protrusion direction of the convex portion 35 corresponds to the position of the concave portion forming surface before the concave portion is formed (in this case, the inner diameter surface 37 of the shaft fitting hole 22a of the hole portion 22 of the hub wheel 1) . That is, as shown in FIG. 6, the inner diameter dimension D of the inner diameter surface 37 of the shaft fitting hole 22a is set to be larger than the maximum outer diameter of the convex portion 35, that is, the convex portion 35 that connects the convex portion 41a of the spline 41. The diameter dimension (circumscribed circle diameter) D1 of the circle at the top of the apex is smaller than the diameter dimension D2 of the circle connecting the valley bottom between the convex parts (the bottom of the recess 41b of the spline 41). That is, D2VDVD1. Therefore, the convex portion 35 of the shaft portion 12 is press-fitted into the inner diameter surface 37 of the shaft portion fitting hole 22a of the hub wheel 1 from at least the apex to the middle portion in the protruding direction.

[0180] The spline 41 can be formed by various processing methods such as rolling processing, cutting processing, press processing, and drawing processing, which are conventionally known and commonly used means. In addition, various heat treatments such as induction hardening and carburizing quenching can be used as the thermal hardening treatment.

CN 101802425 Β

[0181] In addition, as shown in FIG. 3, the short cylindrical portion 66 used to form the tapered locking piece 65 protrudes in the axial direction from the outer peripheral edge portion of the end surface 12a of the shaft portion 12. The outer diameter D4 of the short cylindrical portion 66 is set to be smaller than the inner diameter dimension D of the shaft fitting hole 22a of the hole portion 22. That is, the short cylindrical portion 66 constitutes an alignment member when the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1 as described later.

[0182] Also, as shown in FIG. 3, a sealing member 99 such as an O-ring is fitted on the root joint (mouth side) of the shaft portion 12 of the outer ring 5. In the state of the shaft core of the outer ring 5 of the joint 3, the shaft portion 12 of the outer ring 5 is inserted (press-fitted) into the hub ring 1. In addition, the surface of the convex portion 35 is coated with a seal in advance. At this time, since the hole 22 of the hub wheel 1 is formed with a tapered portion 22d whose diameter is reduced in the press-fitting direction, the tapered portion 22d can be configured as a guide at the start of press-fitting. In addition, the diameter dimension D of the inner diameter surface 37 of the shaft fitting hole 22a, the diameter dimension D1 of the convex portion 35, and the diameter dimension D2 of the concave portion of the spline 41 are in the above-mentioned relationship, and the hardness of the convex portion 35 is higher than that of the shaft portion. The hardness of the inner diameter surface 37 of the engaging hole 22a is greater than 20 points. Therefore, if the shaft 10 is pressed into the hole 22 of the inner ring 6, the convex portion 35 bites into the inner diameter surface 37, and the convex portion 35 forms the convex portion along the axial direction. 35 into which the recess 36 is fitted.

[0183] Through such press-fitting, as shown in FIG. 2, the convex portion 35 at the end of the shaft portion 12 and the fitting contact portion 38 of the concave portion 36 fitted therewith are in close contact with each other over the entire area. That is, the transfer of the shape of the convex portion 35 is performed on the concave portion forming surface on the other side (in this case, the inner diameter surface 37 of the shaft fitting hole 22 a of the hole portion 22 ). At this time, the convex portion 35 bites into the inner diameter surface 37 of the shaft fitting hole 22a, so that the shaft fitting hole 22a has a slightly enlarged diameter, allowing the convex portion 35 to move in the axial direction. When it stops, the hole portion 22 is reduced in diameter in order to return to its original diameter. In other words, the hub wheel 1 is elastically deformed in the radial direction when the convex portion 35 is press-fitted, and the preload of the elastic deformation amount is applied to the tooth surface of the convex portion 35 (the surface of the concave portion fitting portion). Therefore, it is possible to reliably form the concave-convex fitting structure Mo in which the entire concave portion fitting portion of the convex portion 35 is in close contact with the corresponding concave portion 36.

[0184] In addition, a seal member 99 such as an O-ring is externally fitted on the root portion (mouth side) of the shaft portion 12 of the outer ring 5. Therefore, in the state where the press-fitting is completed, the fastening portion 31 of the hub ring 1 and the mouth portion The gap 98 between the back surfaces 11 a of 11 is closed (sealed) by the sealing member 99. In addition, the fitting contact portion 38 between the convex portion 35 and the concave portion 36 is sealed by a sealing material applied to the surface of the convex portion 35.

[0185] When the shaft portion 12 of the outer ring 5 is pressed into the hole portion 22 of the hub wheel 1, a step surface G may be provided on the outer diameter surface of the mouth portion 11 of the outer ring 5 as shown in FIG. The tool K is engaged with the step surface G, and a press-in load (axial load) is applied to the step surface G from the press-in tool K. In addition, the step surface G may be provided on the entire circumference in the circumferential direction, and may be provided at a predetermined pitch along the circumferential direction. Therefore, as the press-fitting tool K used, an axial load can be given corresponding to these stepped surfaces G.

[0186] In this way, the shaft portion 12 of the outer ring 5 is pressed into the hole portion 22 of the hub ring 1, and the shaft portion 12 of the outer ring 5 is integrated with the hub ring 1 via the concave-convex fitting structure M, as shown in FIG. 4 As shown, the short cylindrical portion 66 protrudes from the shaft fitting hole 22a to the tapered hole 22b side.

[0187] Therefore, the short cylindrical portion 66 is enlarged in diameter using the tool 67. In this case, the outer diameter surface of the short cylindrical portion 66 is pre-coated with a seal that constitutes the foreign matter intrusion prevention mechanism W2 on the external side. The tool 67 has a cylindrical body portion 68 and a truncated cone portion 69 connected to the front end of the body portion 68. The truncated cone portion 69 of the tool 67 is set so that the inclination angle of the inclined surface 69a is approximately the same as the inclination angle of the tapered hole 22b, and the outer diameter of the front end is the same as the inner diameter of the short cylindrical portion 66 and even smaller than that of the short cylindrical portion 66. The inner diameter is slightly smaller. And, as shown in FIG. 4, the truncated cone portion 69 of the tool 67 is inserted through the tapered hole 22b to apply a load in the direction of the arrow α, thereby imparting a load on the inner diameter side of the short cylindrical portion 66 shown in FIG. The diameter of the short cylindrical portion 66 is expanded by an expansion force in the direction of the arrow β. At this time, through the truncated cone portion 69 of the tool 67,

CN 101802425 Β

At least a part of the short cylindrical portion 66 is pressed toward the inner diameter surface side of the tapered hole 22b, and the inner diameter surface of the tapered hole 22b is in a crimped or even contacted state via a seal that constitutes the foreign matter intrusion prevention mechanism W2. The shaft part anti-off structure M1. In addition, when a load in the direction of arrow α of the tool 67 is applied, the wheel bearing device needs to be fixed and does not move in the direction of arrow α, but only a part of the hub ring 1 or the constant velocity universal joint 3 etc. can be received by the fixing member. . Among them, the inner diameter surface of the short cylindrical portion 66 may be a tapered shape whose diameter is enlarged toward the shaft end side. If it is formed into such a shape, the inner diameter surface can be formed by forging, and cost reduction can be achieved.

[0188] In addition, in order to reduce the load in the arrow α direction of the tool 67, a notch may be added to the short cylindrical portion 66, and the conical surface of the truncated cone portion 69 of the tool 67 may be partially arranged in the circumferential direction. When a notch is added to the short cylindrical portion 66, the short cylindrical portion 66 can be easily enlarged in diameter. In addition, when the conical surface of the truncated cone portion 69 of the tool 67 is partially arranged in the circumferential direction, the portion where the diameter of the short cylindrical portion 66 is enlarged constitutes a part of the circumference, so the press-fitting load of the tool 67 can be reduced.

[0189] In the concave-convex fitting structure M, as shown in FIG. 6, the outer diameter of the shaft portion 12 (the diameter of the circle connecting the top of the convex portion 35) D1 and the shaft of the hole 22 of the hub wheel 1 are set. The diameter difference (D1-D) of the inner diameter dimension D of the fitting hole 22a is set to the height of the convex portion 35 disposed on the outer diameter surface of the shaft portion 12 as h, which is a ratio of 4 (1/211, 0.3 &lt;Δ d/2h &lt;0.86 ο Thus, the middle part of the protrusion direction (the middle part in the height direction) of the convex portion 35 is reliably arranged on the concave portion forming surface before the concave portion is formed, so that the convex portion 35 bites into the concave portion during press-fitting On the forming surface, the recess 36 can be reliably formed.

[0190] The concave-convex fitting structure M is configured in this way, but the concave-convex fitting structure M in this case is preferably arranged at an avoiding position just below the raceway surfaces 26, 27, 28, and 29 of the rolling bearing 2. Here, the "just below avoidance position" refers to a position that does not correspond to the position of the ball contact portion of the raceway surfaces 26, 27, 28, 29 in the radial direction.

[0191] In the present invention, the concave-convex fitting structure M has the convex portion 35 and the entire area of the fitting contact portion 38 of the concave portion 36 in close contact, so the concave-convex fitting structure M is not formed to generate rattling in the radial and circumferential directions. Clearance. Therefore, the entire fitting portion contributes to the transmission of the rotational torque, and stable torque transmission can be realized, and no noise is generated.

[0192] The hardness difference between the press-fitting start end of the convex portion 35 and the concave portion forming part is 20HRC or more. Therefore, when the convex portion 35 is press-fitted toward the other side, only a small press-fitting force (press-fitting load) can be applied. ) Press-fitting can improve press-fitting properties. In addition, since a large press-in load can not be applied, it is possible to prevent abrasion or damage (cracking) of the convex portion 35 and the concave portion 36, and it is possible to stably form the unevenness that does not generate a gap in the radial and circumferential directions. Mosaic structure Mo

[0193] If the hardness of the convex portion is 50 to 65 HRC, a harder convex portion and a more stable concave-convex fitting structure can be formed. In addition, if the hardness of the recessed portion formation portion is 10 to 30 HRC, the recessed portion forming side can be softer and the pressability can be improved.

[0194] The convex portion can be heat-treated and hardened by high-frequency heat treatment. If the convex portions are hardened by high frequency heat treatment, there are advantages described below. (A) It can be heated locally, and it is easy to adjust the quenching conditions. (B) Since it can be heated in a short time, there is little oxidation. (C) Compared with other quenching methods, there is no quenching warpage. (D) The surface hardness is high, and excellent abrasion resistance can be obtained. (E) The selection of the depth of the hardened layer is also easier. (F) It is easy to automate and can also be assembled on a machining line.

[0195] By providing the foreign matter intrusion prevention mechanism W, it is possible to prevent foreign matter from intruding into the concave-convex fitting structure M. That is, by preventing the intrusion of rainwater or foreign matter by the foreign matter intrusion prevention mechanism W, it is possible to prevent rainwater, foreign matter, etc. from entering the concave-convex fitting structure M and deterioration of adhesion.

[0196] In the structure in which the sealing member 99 is arranged between the end of the hub wheel 1 and the bottom of the mouth 11, the gap 98 between the end of the hub wheel 1 and the bottom of the mouth 11 is closed by the sealing member 99, This can prevent rain or foreign objects from

CN 101802425 Β

This gap 98 intrudes into the concave-convex fitting structure M. As the sealing member 99, as long as it can be interposed between the end of the hub wheel 1 and the bottom of the mouth 11, for example, an existing (commercially available) O-ring can be used, and it can be configured to prevent foreign matter at low cost. The intrusion mechanism, and the commercially available O-rings, etc., are available in various materials and sizes, and do not need to be specially made to form a foreign matter intrusion prevention mechanism that reliably performs the sealing function.

[0197] A seal is interposed between the convex portion 35 of the concave-convex fitting structure M and the fitting contact portion 38 of the concave portion 36, so that the intrusion of foreign matter between the fitting contact portion 38 can be prevented, and the reliability of the prevention of foreign matter intrusion can be improved. .

[0198] On the outer side of the concave-convex fitting structure M, the inner diameter surface of the hub wheel 1 (in this case, the inner diameter surface of the tapered hole 22b) is provided with a via seal (a sealing member constituting the foreign matter intrusion prevention mechanism W2) The engaging portion (taper-shaped locking piece 65) that engages, so it can prevent foreign matter from entering from the external side.

[0199] In this way, as shown in the above-mentioned embodiment, when the foreign matter intrusion prevention mechanism W1, W2 is provided on the built-in side of the concave-convex fitting structure M and the outer side of the concave-convex fitting structure M, it is prevented from being removed from the concave-convex fitting structure M. Intrusion of foreign bodies on both ends of the axial direction. Therefore, it is possible to more stably avoid deterioration of adhesiveness over a long period of time.

[0200] It is not necessary to form splines and the like on the parts forming the recesses 36 (in this case, the hub ring 1), which is superior in productivity and does not require phase matching of the splines to achieve improved assemblability. In addition, damage to the tooth surface during press-fitting can be avoided, and a stable fitting state can be maintained.

[0201] The tapered portion 22d can constitute a guide at the start of press-fitting, and therefore can be press-fitted into the shaft portion 12 of the outer ring 5 with respect to the hole portion 22 of the hub wheel 1 without deviation, and stable torque transmission can be realized. In addition, the short cylindrical portion 66 is set such that the outer diameter D4 of the short cylindrical portion 66 is smaller than the inner diameter dimension D of the shaft fitting hole 22a of the hole 22, so it constitutes a centering member that can prevent eccentricity and core tilt. At the same time, the shaft can be pressed into the hub ring, which can realize more stable pressing.

[0202] The shaft portion anti-disengagement structure M1 can effectively prevent the shaft portion 12 of the outer ring 5 from detaching from the hole portion 22 of the hub wheel 1 (especially detachment in the axial direction on the shaft side). As a result, a stable connection state can be maintained, and the quality of the wheel bearing device can be improved. In addition, since the shaft portion anti-disengagement structure M1 is a tapered locking piece 65, it is possible to omit the conventional screw connection. Therefore, it is not necessary to form a threaded portion protruding from the hole portion 22 of the hub wheel 1 on the shaft portion 12, and the weight can be reduced, and the screwing operation can be omitted, and the assembling workability can be improved. In addition, in the tapered locking piece 65, as long as the diameter of a part of the shaft portion 12 of the outer ring 5 is enlarged, the shaft portion stopper structure M1 can be easily formed. In addition, the movement of the shaft portion 12 of the outer ring 5 in the direction opposite to the joint requires pressing force in the direction to further press the shaft portion 12, and the positional deviation of the shaft portion 12 of the outer ring 5 in the direction opposite to the joint is extremely difficult to occur, and Even if a positional deviation occurs in this direction, the bottom of the mouth portion 11 of the outer ring 5 abuts the fastening portion 31 of the hub ring 1, and the shaft portion 12 of the outer ring 5 will not be separated from the hub ring 1.

[0203] Since the axial end portion of the convex portion of the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 has a higher hardness than the inner diameter portion of the hole portion of the hub ring 1, the shaft portion 12 is directed to the hole portion of the hub ring 1. Since the portion 22 is press-fitted from the axial end side of the convex portion 35, it is easy to form a concave portion on the inner diameter surface of the hole of the hub wheel 1. In addition, the hardness on the shaft portion side can be increased, and the torsion strength of the shaft portion 12 can be improved.

[0204] In addition, since the end portion of the hub ring 1 is fastened and preloaded with respect to the rolling bearing 2, it is not necessary to give the preload by the mouth portion 11 of the outer ring 5. Therefore, the shaft portion 12 of the outer ring 5 can be press-fitted without considering the preload, and the connection (assemblability) between the hub ring 1 and the outer ring 5 can be improved.

[0205] In addition, when the fastening portion 31 of the hub wheel 1 is brought into abutment (contact) with the back surface 11a of the mouth portion 11, the positioning of the shaft portion 12 of the outer ring 5 can be configured. By positioning in this way, the dimensional accuracy of the wheel bearing device can be stabilized, and the axial length of the concave-convex fitting structure M arranged along the axial direction can be ensured to be a stable length, and the torque transmission performance can be improved. . However, the contact surface between the fastening portion 31 of the hub ring 1 and the back surface 11a of the mouth portion 11 is slightly pressed.

CN 101802425 Β

More than 100MPa, will produce noise. That is, under a large torque load, the amount of twist between the outer ring 5 of the constant velocity universal joint 3 and the hub ring 1 will deviate, and this deviation will cause the contact between the outer ring 5 of the constant velocity universal joint 3 and the hub ring 1 There was a sharp sliding on the head and noise occurred. In contrast, when the fastening portion 31 is brought into contact with the back surface 11a of the mouth portion 11, the contact surface pressure is 100 MPa or less, so that abrupt sliding can be prevented and the generation of noise can be suppressed. As a result, a quiet wheel bearing device can be constructed.

[0206] By arranging the concave-convex fitting structure M at an avoiding position (a straight-down position) just below the raceway surface of the rolling bearing 2, the occurrence of hoop stress on the bearing raceway surface can be suppressed to a minimum. As a result, it is possible to prevent bearing defects such as reduction in rolling fatigue life, generation of cracks, and stress corrosion fracture from occurring, and it is possible to provide a high-quality bearing.

[0207] As shown in the above-mentioned embodiment, the spline 41 formed on the shaft portion 12 uses small teeth with a modulus of 0.5 or less. Therefore, the formability of the spline 41 can be improved and the press-fitting load can be reduced. reduce. In addition, since the convex portion 35 can be formed by a spline normally formed on such a shaft, the convex portion 35 can be easily formed at a low cost.

[0208] In addition, when the recessed portion 36 is formed by pressing the shaft portion 12 into the hub wheel 1, work hardening occurs on the side of the recessed portion 36. Here, work hardening means that when plastic deformation (plastic working) is given to an object, as the degree of deformation increases, the resistance to deformation increases and becomes harder than a material that has not undergone deformation. Therefore, the inner diameter surface 37 of the hub wheel 1 on the side of the recessed portion 36 is hardened by plastic deformation during press-fitting, so that the transmission of the rotational torque can be improved.

[0209] The inner diameter side of the hub ring 1 is relatively soft. Therefore, it is possible to achieve an improvement in fitting (adhesion) when the convex portion 35 on the outer diameter surface of the shaft portion 12 of the outer ring 5 is fitted into the concave portion 36 on the inner diameter surface of the hole portion of the hub wheel 1, and it is possible to accurately suppress Shake occurs in the radial direction and the circumferential direction.

[0210] In the present invention, the hardening and tempering of the hub ring 1 is performed, so that the fatigue strength of the material can be improved, so that the size and weight can be reduced, and at the same time, the strength and durability of the hub ring 1 can be improved. In addition, the surface vibration that is the cause of brake chattering is not deteriorated, and the fixing strength of the hub bolt is ensured.

[0211] The surface hardness of the hardened layer H1 can be HRC54 to HRC64. As a result, in the outer diameter surface of the hub wheel 1, not only the wear resistance from the inner side root joint 127 of the wheel mounting flange 21 to the inner side and the inner raceway surface 28.29 on the outer side is improved, but also the mechanical The strength of the wheel further improves the strength and durability of the hub ring 1.

[0212] The inner side end is plastically deformed radially outward to form a fastening portion 31. In the hub ring 1 in which the inner ring 24 is fixed in the axial direction by the fastening portion 31, the inner side end of the hub ring 1 The surface hardness of the part is set to 25HRC or less. As a result, since the fastening portion 31 can be formed at the end of the hub ring, it is not necessary to tighten the nut or the like to manage the preload amount as in the past, so it is easy to assemble to the vehicle, and the preload amount can be maintained for a long period of time. . In addition, compared with the unheated portion after forging as in the past, the workability is not reduced, and the surface is not microcracked due to plastic working, and the reliability can be further improved in terms of quality.

[0213] In the case of using a medium carbon steel with a carbon content of 0.4 wt% to 0.8 wt% for the hub ring 1, it is advantageous in terms of ease of forging, machinability, heat treatment, or economy, and particularly It is suitable for high-frequency quenching, etc.

[0214] FIG. 8 shows a second embodiment. The shaft portion anti-disengagement structure M1 of the wheel bearing device does not have to form a short cylindrical portion 66 as shown in FIG. 4 in advance, but is provided as a part of the shaft portion 12 The taper-shaped locking piece 70 of the engaging part protruding in the outer diameter direction is comprised.

[0215] In this case, the tool 71 shown in FIGS. 9 and 10 is used. The tool 71 has a cylindrical body portion 72 and a short cylindrical portion 73 connected to the front end of the body portion 72, and a notch 74 is provided at the front end of the outer peripheral surface of the short cylindrical portion 73. Therefore, a tip wedge 75 is formed on the tool 71. If it hits the tip wedge portion 75 (if a load in the direction of arrow α is applied), the cross-sectional shape of the tip wedge portion 75 has an inclined surface on the outer diameter side, and through the notch 74 that forms the inclined surface, such as

CN 101802425 Β

As shown in FIG. 10, the outer diameter side of the end part of the shaft part 12 is enlarged.

[0216] Thus, at least a part of the tapered locking piece 70 is crimped or even contacts the inner diameter surface of the tapered hole 22b. Therefore, even such a tapered locking piece 70 can effectively prevent the shaft portion 12 of the outer ring 5 from moving in the axial direction from the hole portion 22 of the hub ring 1, similarly to the tapered locking piece 65 shown in FIG. 1 and the like. On detachment. As a result, a stable connection state can be maintained, and the quality of the wheel bearing device can be improved. In addition, the inner diameter surface of the tip wedge portion 75 may have a tapered shape.

[0217] FIG. 11 shows a third embodiment. The shaft portion stopping structure M1 of the wheel bearing device is constituted by an outer handcuff-shaped locking piece 76 formed by fastening a part of the shaft portion 12 to protrude in the outer diameter direction . In this case, the hole portion 22 of the hub wheel 1 is provided with a stepped surface 22e between the shaft fitting hole 22a and the tapered hole 22b, and the stepped surface 22e is locked with an outer handcuff-shaped lock as an engaging portion.sheet76.

[0218] In the shaft portion anti-drop structure M1, a tool 77 shown in FIG. 12 is used. The tool 77 is provided with a cylindrical body 78. The outer diameter D5 of the cylindrical body 78 is set to be larger than the outer diameter D7 of the end of the shaft portion 12, and the inner diameter D6 of the cylindrical body 78 is set to be smaller than the outer diameter D7 of the end of the shaft portion 12.

[0219] Therefore, by aligning the tool 77 with the shaft core of the shaft portion 12 of the outer ring 5, the end surface 77a of the tool 77 in this state applies a load to the end surface 12a of the shaft portion 12 in the arrow α direction, as As shown in FIG. 13, the outer peripheral side of the end surface 12a of the shaft part 12 is crushed, and the outer cuff-shaped locking piece 76 can be formed.

[0220] Even with such an outer handcuff-shaped locking piece 76, the outer handcuff-shaped locking piece 76 can be locked with the step surface 22e, so it can be similar to the tapered locking piece 65 shown in FIG. 1 and the like. This effectively prevents the shaft portion 12 of the outer ring 5 from being separated from the hole portion 22 of the hub ring 1 in the axial direction. As a result, a stable connection state can be maintained, and the quality of the wheel bearing device can be improved.

[0221] If the tool 77 shown in FIGS. 12 and 13 is used, as shown in FIG. 14A, the outer handcuff-shaped locking piece 76 is formed along the circumferential direction. Therefore, if the pressing portions are arranged at a predetermined pitch (for example, 90° pitch) in the circumferential direction as a tool, as shown in FIG. 14B, the plurality of outer handcuff-shaped locking pieces 76 are arranged at a predetermined pitch in the circumferential direction. Even if a plurality of outer handcuff-like locking pieces 76 are arranged at a predetermined pitch in the circumferential direction as shown in FIG. 14B, the outer handcuff-like locking pieces 76 are locked with the step surface 22e, so that the shaft portion of the outer ring 5 can be effectively prevented 12 is separated from the hole 22 of the hub ring 1 in the axial direction.

[0222] When the shaft portion 12 of the outer ring 5 is pressed into the hub wheel 1, the material overflows from the concave portion 36 formed by the convex portion 35 to form an overflow portion 45 shown in FIG. 16. The overflow portion 45 is the amount of material of the volume of the concave portion 36 into which the concave portion of the convex portion 35 is fitted (fitted), is pressed out from the formed concave portion 36, is cut off to form the concave portion 36, or is Composed of both extruded and cut off.

[0223] Therefore, in the wheel bearing device shown in FIG. 1 and the like described above, after the constant velocity universal joint is assembled to the hub wheel 1, the overflow portion 45 needs to be removed. Therefore, in the fourth embodiment shown in FIG. 15, as described above, the recessed portion 50 that accommodates the overflow portion 45 is provided on the shaft portion 12 ±o.

[0224] By providing a circumferential groove 51 on the shaft end edge of the spline 41 of the shaft portion 12, the recess portion 50 is formed. In this case, as shown in the mesh section of FIG. 17, a hardened layer Ho is formed from the outer edge of the spline 41 to a part of the bottom wall of the mouth 11 of the outer ring 5.

[0225] When the shaft core of the hub ring 1 is aligned with the shaft core of the outer ring 5 of the constant velocity universal joint 3, the shaft portion 12 is pressed into the hole portion 22 of the hub ring 1, and the resulting overflow As shown in FIG. 16, the portion 45 is stored in the recessed portion 50 while being curled. That is, a part of the material from which the inner diameter surface of the hole portion 22 is shaved or pressed out enters the recess portion 50.

[0226] In this way, by providing the recessed portion 50 for accommodating the overflow portion 45 generated by the formation of the press-fitted recessed portion, the overflow portion 45 can be held (maintained) in the recessed portion 50 without overflowing Part 45 to the inside of the vehicle outside the device, etc.

CN 101802425 Β

enter. In other words, the overflow portion 45 can be stored in the recessed portion 50 in advance, and removal processing of the overflow portion 45 is not necessary. Assembling work man-hours can be reduced, and assembling workability can be improved and costs can be reduced.

[0227] In addition, since the short cylindrical portion 66 protrudes into the tapered hole 22b after the press-fitting is completed, it is necessary to increase the diameter of the short cylindrical portion 66. Therefore, by using the tool 67 shown in FIG. 4, the diameter can be expanded, and if the diameter of the short cylindrical portion 66 is expanded, the shaft portion stopper structure M1 is formed.

[0228] Even the wheel bearing device shown in FIG. 8, FIG. 11, FIG. 15 and the like is provided with the foreign matter intrusion prevention mechanism W1 on the internal side, the foreign matter intrusion prevention mechanism W2 on the external side, and the fitting contact portion 38. Anti-foreign body intrusion mechanism W3_OIn addition, the foreign matter intrusion prevention mechanism W2 in FIG. 8 is configured by coating the outer surface of the tapered locking piece 70 with a sealing material. In addition, the foreign matter intrusion prevention mechanism W2 in FIG. 11 is configured by coating a sealing material on the surface corresponding to the step surface 22e of the outer handcuff-shaped locking piece 76.

[0229] As the shaft anti-disengagement structure M1, a bolt and nut connection may be used as shown in FIG. 18 of the fifth embodiment, or a retaining ring may be used as shown in FIG. 19 of the sixth embodiment, or it may be as shown in the seventh embodiment. Figure 20 shows the use of welding and other bonding mechanism.

[0230] In FIG. 18, a threaded shaft portion 80 is connected to the shaft portion 12, and a nut member 81 is screwed on the threaded shaft portion 80. In addition, the nut member 81 is brought into contact with the step surface 22e of the hole 22. Thereby, the shaft portion 12 is restricted from being separated from the hole portion 22 of the hub wheel 1 to the shaft side. In other words, the nut member 81 constitutes the engagement portion of the shaft portion stopper structure M1. The wheel bearing device of FIG. 18 is also provided with a built-in side foreign matter intrusion prevention mechanism W1 and a foreign matter intrusion prevention mechanism W3 between the fitting contact portion 38, and a seal is coated on the corresponding surface of the step surface 22e of the nut member 81, thereby Structure W2 to prevent foreign matter intrusion_O[0231] In FIG. 19, a shaft extension 83 is provided on the outer side of the spline 41, and a circumferential groove 84 is provided on the shaft extension 83, and a retaining ring 85 is fitted into the circumferential groove 84. In addition, the shaft portion 12 is provided in the hole portion 22 of the hub ring 1 between the shaft portion fitting hole 22a and the tapered hole 22b to lock the step portion 22f of the retaining ring 85. Thus, the retaining ring 85 and the step The portion 22f is locked and restricts the shaft portion 12 from being detached from the hole portion 22 of the hub wheel 1 to the shaft side. In other words, the retaining ring 85 constitutes an engaging portion of the shaft portion anti-disengagement structure M1. The wheel bearing device of FIG. 19 is also provided with a built-in foreign matter intrusion prevention mechanism W3 and a foreign matter intrusion prevention mechanism W3 between the fitting contact portion 38, and a foreign matter intrusion prevention mechanism W2o is formed by a retaining ring 85

[0232] In FIG. 20, the outer peripheral surface of the end portion of the shaft portion 12 and the end edge portion of the opening portion on the side of the step surface 22e of the shaft portion fitting hole 22a are joined by welding. Thereby, the shaft portion 12 is restricted from detaching from the hole portion 22 of the hub wheel 1 to the shaft side. That is, the welding portion 88 constitutes the engaging portion of the shaft portion anti-disengagement structure M1. In this case, the welding part 88 may be arranged at a predetermined pitch in the circumferential direction over the entire circumference. The wheel bearing device of FIG. 20 is also provided with a built-in side foreign matter intrusion prevention mechanism W1 and a foreign matter intrusion prevention mechanism W3 between the fitting contact portions 38, and a foreign matter intrusion prevention mechanism W2 is formed by a welding portion 88.

[0233] In the bearing device for a wheel of the present invention, as shown in FIG. 21, the shaft portion anti-disengagement structure M1 may not be provided. In this case, as shown in FIG. 22, the side surface 51a on the spline 41 side of the circumferential groove 51 is a plane perpendicular to the axial direction, and the side surface 51b on the opposite side of the spline expands from the groove bottom 51c to the opposite side of the spline. The tapered surface of the diameter. In addition, a disc-shaped shaft extension 52 for alignment is provided on the side opposite to the spline of the side surface 51 b of the circumferential groove 51. The outer diameter dimension D4a (refer to FIG. 22) of the shaft extension portion 52 is set to be the same as the diameter of the shaft portion fitting hole 22a of the hole portion 22 or even slightly smaller than the diameter of the shaft portion fitting hole 22a. In this case, a minute gap t is provided between the outer diameter surface 52a of the shaft extension portion 52 and the inner diameter surface of the shaft fitting hole 22a of the hole 22.

[0234] A shaft extension 52 for aligning with the hole 22 of the hub ring 1 is provided on the opposite side of the axial convex portion of the recess 50, so that the overflow 45 in the recess 50 does not extend to the shaft extension. The 52 side flies out, and the storage of the overflow part 45 becomes more stable

CN 101802425 Β

set. In addition, the shaft extension 52 is used for alignment, so that eccentricity can be prevented and the shaft 12 can be pressed into the hub ring 1. Therefore, the outer joint member 5 and the hub wheel 1 can be connected with high precision, and stable torque transmission can be performed.

[0235] The shaft extension 52 is used for alignment during press-fitting, so its outer diameter is preferably set to be slightly smaller than the diameter of the shaft fitting hole 22a of the hole 22 of the hub wheel 1. That is, if the outer diameter of the shaft extension 52 is the same as or larger than the diameter of the shaft fitting hole 22a, the shaft extension 52 itself is press-fitted into the shaft fitting hole 22a. At this time, if eccentricity occurs, the convex portion 35 of the concave-convex fitting structure M is directly pressed in, and the shaft portion 12 and the hub ring 1 are in a state where the shaft core of the shaft portion 12 and the shaft core of the hub ring 1 are not aligned. link. In addition, if the outer diameter dimension of the shaft extension part 52 is too small compared with the hole diameter of the shaft part fitting hole 22a, it will not function as an alignment function. Therefore, the minute gap t between the outer diameter surface 52a of the shaft extension portion 52 and the inner diameter surface of the shaft fitting hole 22a of the hole 22 is preferably set to about 0.01 mm to 0.2 mm.

[0236] In addition, in the wheel bearing device shown in FIG. 21, the foreign matter intrusion prevention mechanism W1 and the foreign matter intrusion prevention mechanism W3 are provided, but the foreign matter intrusion prevention mechanism W2 is not provided. In addition, as shown in FIG. 21, in the case where the shaft portion anti-disengagement structure M1 is not provided, the shaft extension portion 52 for the alignment of the shaft portion 12 may be omitted.

[0237] Next, FIG. 23 shows a wheel bearing device that allows the shaft portion 12 to be separated from the hub wheel 1. In this case, as shown in FIGS. 23 and 24, the hub wheel 1 also has a cylindrical portion 20 and a flange 21 provided at an end portion on the outer side of the cylindrical portion 20. The hole portion 22 of the cylindrical portion 20 has a shaft fitting hole 22a in the axial middle portion and a tapered hole 22b on the outer side. A projecting inner diameter is provided between the shaft fitting hole 22a and the tapered hole 22b. The inner wall is 22g. That is, the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 and the hub ring E are coupled to the shaft portion fitting hole 22a via the concave-convex fitting structure M. In addition, the shaft portion on the opposite side of the shaft portion fitting hole E on the inner wall 22g A recess 91 is provided on the end surface.

[0238] The hole portion 22 has a large diameter portion 86 on the opening side opposite to the inner wall of the shaft fitting hole 22a, and a small diameter portion 88 on the inner wall side of the shaft fitting hole 22a. A tapered portion (tapered hole) 89a is provided between the large diameter portion 86 and the shaft portion fitting hole 22a. The tapered portion 89a is reduced in diameter along the press-fitting direction when the hub wheel 1 and the shaft portion 12 of the outer ring 5 are joined. The taper angle θ of the taper portion 89a is, for example, 15° to 75°. In addition, a tapered portion 89b is also provided between the shaft portion fitting hole 22a and the small diameter portion 88.

[0239] In this case, by pressing the shaft portion 12 into the hole portion 22 of the hub wheel 1, that is, the shaft portion fitting hole 22a, the shaft portion

The convex portion 35 of 12 forms a concave portion 36 into which the convex portion 35 is closely fitted on the inner diameter surface 37 of the shaft fitting hole 22a.

[0240] In addition, the bolt member 94 is screwed into the threaded hole 90 of the shaft portion 12 from the outer side after press-fitting. The bolt member 94 is composed of a flanged head 94a and a threaded shaft 94b. The threaded shaft portion 94b has a large-diameter base portion 95a, a small-diameter body portion 95b, and a threaded portion 95c on the tip side_oIn this case, a through hole 96 is provided in the inner wall 22 g, and the shaft portion 94 b of the bolt member 94 is inserted through the through hole 96, and the threaded portion 95 c is screwed into the threaded hole 90 of the shaft portion 12. As shown in FIG. 24, the diameter d1 of the through hole 96 is set to be slightly larger than the outer diameter d2 of the large-diameter base portion 95a of the shaft portion 94b. Specifically, it is set at about 0.05 mm &lt;dl-d2 &lt;0.5 mm. In addition, the maximum outer diameter of the threaded portion 95c is the same as the outer diameter of the large-diameter base portion 95a or is slightly smaller than the outer diameter of the base portion 95a.

[0241] In this way, by screwing the bolt member 94 to the threaded hole 90 of the shaft portion 12, the flange portion 100 of the head 94a of the bolt member 94 is fitted into the recessed portion 91 of the inner wall 22g. As a result, the inner wall 22g is sandwiched by the end surface 92 on the outer side of the shaft portion 12 and the head portion 94a of the bolt member 94_o

[0242] In addition, a seal (not shown) may be interposed between the support surface 100a of the bolt member 94 and the inner wall 22g. In this case, for example, as long as the support surface 100a of the bolt member 94 is coated with a seal composed of various resins that are cured after coating and can exert a seal between the support surface 100a and the bottom surface of the recessed portion 91 of the inner wall 22g Parts (sealant). In addition, as the seal, a material that does not deteriorate in the atmosphere in which the wheel bearing device is used is selected.

CN 101802425 Β

[0243] In addition, the inner wall 22g may not be sandwiched between the end surface 92 of the shaft portion 12 and the bolt member 94a. In this case, the hub wheel 1 is sandwiched between the head 54a of the bolt member 54 and the concave-convex fitting structure M, or the head 54a of the bolt member 54 and the back surface 11a of the mouth 11. That is, the fastening portion 31 of the hub wheel is brought into contact with the back surface 11a of the mouth portion 11 (illustration omitted). As a result, the bending rigidity in the axial direction is improved, the resistance to bending becomes stronger, and a high-quality product with excellent durability is obtained. Furthermore, the positioning at the time of press-fitting can be constructed by this contact. Thereby, the dimensional accuracy of the wheel bearing device is stable, and the axial length of the concave-convex fitting structure M arranged along the axial direction can be ensured at a stable length, and the torque transmission can be improved. In addition, the sealing structure can be constructed by this contact, and foreign matter can be prevented from intruding into the concave-convex fitting structure M from the fastening portion 31 side, and the concave-convex fitting structure M can maintain a stable fitting state for a long time.

[0244] Since a seal is interposed between the bearing surface 100a and the inner wall 22g of the bolt member 94 for bolt-fixing the shaft portion 12 of the hub ring 1 and the outer ring 5, it is possible to prevent the bolt member 94 from fitting into the uneven The structure Μ invades rainwater or foreign objects to achieve quality improvement.

[0245] Starting from the state shown in FIG. 23, by unscrewing the bolt member 94 to remove the bolt member 94, the outer ring 5 can be removed from the hub ring 1. That is, the fitting force of the concave-convex fitting structure M is the extent that the outer ring 5 can be stretched only by applying a tensile force greater than a predetermined force.

[0246] For example, the hub wheel 1 and the constant velocity universal joint 3 can be separated by a tool 120 as shown in FIG. 26. The tool 120 is provided with a base plate 121, a pressing bolt member 123 screwed into the threaded hole 122 of the base plate 121 so as to be screwed, and a threaded shaft 76 screwed to the threaded hole 90 of the shaft portion 12. The base plate 121 is provided with a through hole 124, the bolt 123 of the hub ring 1 is inserted into the through hole 124, and the nut member 125 is screwed with the bolt 123. At this time, the base plate 121 overlaps with the flange 21 of the hub ring 1, and the base plate 121 is mounted on the hub ring E

[0247] In this way, after the base 121 is mounted on the hub wheel 1, the threaded shaft 126 is screwed into the threaded hole 90 of the shaft portion 12 so that the base portion 126a protrudes from the inner wall 22g to the outward side. The protrusion amount of the base 126a is set to be longer than the axial length of the concave-convex fitting structure M. In addition, the threaded shaft 126 and the pressing bolt member 123 are arranged on the same shaft core (the shaft core of the wheel bearing device).

[0248] Thereafter, as shown in FIG. 26, the pressing bolt member 123 is screwed into the threaded hole 122 of the base plate 121 from the external side, and in this state, it is screwed to the screw shaft 126 side as shown by the arrow. . At this time, since the threaded shaft 126 and the pressing bolt member 123 are arranged on the same shaft core (on the shaft core of the wheel bearing device), this screwing causes the pressing bolt member 123 to press the thread in the direction of the arrow.axis126. As a result, the outer ring 5 moves in the arrow direction with respect to the hub ring 1, and the outer ring 5 is detached from the hub ring 1.

[0249] In addition, in a state where the outer ring 5 is detached from the hub ring 1, for example, the bolt member 94 can be used to connect the hub ring 1 and the outer ring 5 again. That is, when the base plate 121 is removed from the hub wheel 1 and the threaded shaft 76 is removed from the shaft portion 12, as shown in FIG. 27, the bolt member 94 is screwed into the threaded hole 90 of the shaft portion 12 via the through hole 96. In this state, the phases of the male splines 41 on the side of the shaft portion 12 and the female splines 42 of the hub wheel 1 formed by the previous press-fitting are matched in phase.

[0250] In this state, the bolt member 94 is screwed into the screw hole 90. As a result, the shaft portion 12 is fitted into the hub wheel 1. At this time, if the axial direction of the shaft portion 12 is allowed to enter in the state where the diameter of the hole portion 22 is slightly enlarged, and the movement in the axial direction is stopped, the hole portion 22 is about to return to its original diameter and reduce the diameter. As a result, as with the previous press-fitting, the entire recessed portion fitting portion of the convex portion 35 can reliably form the concave-convex fitting structure Mo that is in close contact with the corresponding concave portion 36.

[0251] In particular, when the bolt member 94 is screwed into the screw hole 90, as shown in FIG. 27, the base portion 95a of the bolt member 94 is formed in a state corresponding to the through hole 96. Furthermore, the hole diameter dl of the through hole 96 is set to be slightly larger than the outer diameter d2 of the large-diameter base 95a of the shaft portion 94b (specifically, set to about 0.05 mm &lt;dl-d2 &lt;0.5 mm), so the bolt part

CN 101802425 Β

The outer diameter of the base 95a of 54 and the inner diameter of the through hole 96 can constitute a guide when the bolt member 94 is screwed into the threaded hole 90, without eccentricity, and the shaft 12 can be pressed into the hole 22 of the hub ring 1 . Similarly, as the axial length of the through hole 96, if it is too short, a stable guiding effect cannot be exerted. On the contrary, if it is too long, the thickness dimension of the inner wall 22g becomes large, and the axial length of the concave-convex fitting structure M cannot be ensured, and The weight of the hub ring 1 becomes larger. Therefore, various changes can be made in consideration of these conditions.

[0252] In addition, the opening of the threaded hole 90 of the shaft portion 12 can form a tapered portion 90a that expands toward the opening side, so there is an advantage that the threaded shaft 126 or the bolt member 94 can be easily screwed into the threaded hole 90.

[0253] In the first time (press-fitting in which the recessed portion 36 is formed on the inner diameter surface 37 of the hole 22), the press-fitting load is relatively large, so for press-fitting, it is necessary to use a punch or the like. In contrast, in such re-pressing, since the press-in load is smaller than the first press-in load, it is possible to press the shaft portion 12 into the hub ring 1 stably and accurately without using a press machine or the like.Hole22. Hole 22. Therefore, the outer ring 5 and the hub ring 1 can be separated and connected on site.

[0254] In the spline 41 shown in FIG. 2 described above, the pitch of the convex portion 41a and the pitch of the concave portion 41b are set to be the same. Therefore, in the above-mentioned embodiment, as shown in FIG. 2B, the circumferential thickness L of the middle portion of the protrusion direction of the convex portion 35 and the circumferential direction at the position corresponding to the middle portion between the convex portions 35 adjacent in the circumferential direction The size L0 is approximately the same.

[0255] On the other hand, as shown in FIG. 28A, the circumferential thickness L2 of the middle portion of the protrusion direction of the convex portion 35 may be greater than the circumferential thickness L2 at the position corresponding to the middle portion between the circumferentially adjacent convex portions 43. The size L1 is small. That is, in the spline 41 formed on the shaft portion 12, the circumferential thickness (tooth thickness) L2 of the middle portion of the convex portion 35 in the protruding direction is larger than that of the convex portion 35 fitted between the convex portions 35 on the hub wheel 1 side. The circumferential thickness (tooth thickness) L1 in the middle part of the direction is small.

[0256] Therefore, the total tooth thickness (B1+B2+B3+...) of the convex portion 35 on the entire circumference of the shaft portion 12 side is set to be higher than that of the convex portion 43 ( The total tooth thickness (A1+A2+A3+......) of the convex teeth is small. Thereby, the shearing area of the convex part 43 on the side of the hub wheel 1 can be enlarged, and torsion strength can be ensured. Furthermore, since the tooth thickness of the convex portion 35 is small, the press-fitting load can be reduced, and the press-fitting property can be improved. In the case where the sum of the circumferential thickness of the convex portion 35 is smaller than the sum of the circumferential thickness on the convex portion 43 on the opposite side, it is not necessary to make the circumferential thickness L2 of the entire convex portion 35 larger than the circumferential thickness L2 of the convex portion 35 adjacent in the circumferential direction. The circumferential dimension L1 is small. That is, among the plurality of convex portions 35, the circumferential thickness of any convex portion 35 may be the same as the circumferential size between adjacent convex portions in the circumferential direction, or may be larger than the circumferential size, as long as the sum is small.

[0257] The convex portion 35 of FIG. 28A has a trapezoidal cross-sectional shape, as shown in FIG. 28B, and may also be in the shape of an involute tooth.

[0258] In each of the above embodiments, the spline 41 constituting the convex portion 35 is formed on the shaft portion 12 side, and the spline 41 of the shaft portion 12 is hardened to keep the inner diameter surface of the hub wheel 1 unhardened ( Raw material). In contrast, as shown in FIG. 29, a hardened spline 111 (consisting of convex bars 111a and concave bars 111b) is formed on the inner diameter surface of the hole 22 of the hub wheel 1, and the shaft may be 12 No hardening treatment is applied. In addition, the spline 111 can be formed by various processing methods such as broaching, cutting, press processing, and drawing processing as well-known and common mechanisms. In addition, various heat treatments such as induction hardening and carburizing quenching can also be used as the thermal hardening treatment.

[0259] In this case, the middle portion of the protrusion direction of the convex portion 35 corresponds to the position of the concave portion forming surface (the outer diameter surface of the shaft portion 12) before the concave portion is formed. That is, the diameter dimension (minimum diameter dimension of the convex part 35) D8 of the circle connecting the top of the convex part 35 as the convex part 111a of the spline 111 is set to be smaller than the outer diameter dimension D10 of the outer diameter surface of the shaft part 12. The diameter of the circle at the bottom of the concave portion 111b of the connecting spline 111 (the inner diameter of the inner diameter surface of the fitting hole between the convex portions) D9 is set to be larger than the outer diameter D10 of the shaft portion 12. Therefore, D8&lt;D10&lt;D9o is constituted. Therefore, the convex portion 35 of the hole portion 22 is pressed into the outer diameter surface of the shaft portion 12 at least from the apex to the middle portion in the protruding direction.

[0260] If the shaft portion 12 is pressed into the hole portion 22 of the hub wheel 1, the convex portion 35 on the side of the hub wheel 1 can be inserted into the shaft portion 12

CN 101802425 Β

The outer peripheral surface of the inner surface forms a concave portion 36 into which the convex portion 35 fits. Thereby, the entire area of the fitting contact portion 38 of the convex portion 35 and the concave portion fitted with the convex portion 35 is in close contact.

[0261] Here, the fitting contact portion 38 is a range B shown in FIG. 29B, from the mountain-shaped midsection of the cross section of the convex portion 35 to the top of the mountain. In addition, between adjacent convex portions 35 in the circumferential direction, a gap 112 is formed on the outer peripheral surface of the shaft portion 12 on the outer diameter side.

[0262] In this case, since the overflow portion 45 is also formed by press-fitting, it is preferable to provide a storage portion 97 for accommodating the overflow portion 45. Since the overflow portion 45 is formed on the mouth side of the shaft portion 12, the receiving portion is provided in the hub ring 1

[0263] In this way, in the structure in which the convex portion 35 of the concave-convex fitting structure M is provided and press-fitted on the inner diameter surface of the hole portion 22 of the hub wheel 1, the hardness treatment (heat treatment) on the shaft portion side is not required, so there are some The productivity of the outer ring 5 of the universal joint 3 is superior.

[0264] As shown in FIG. 31, each of the above-mentioned wheel bearing devices is used in an axle module. The axle module is provided with a constant velocity universal joint T1 on the external side, a constant velocity universal joint T2 on the internal side, and a shaft 10 connecting these constant velocity universal joints T1 and T2. In this case, the hub ring 1, the multi-row rolling bearing (bearing structure portion) 2, and the constant velocity universal joint T1 (3) are integrated on the outer side to form a wheel bearing device. This wheel bearing device uses each of the above-mentioned wheel bearing devices. In addition, in this illustration, similar to the above-mentioned FIG. 15, the end surface of the shaft portion 12 of the outer ring 5 of the constant velocity universal joint T1 is provided with a tapered locking piece 65 and a recessed portion 50. The structure of the wheel bearing device shown in FIG. 31 is the same as that of the wheel bearing device shown in FIG. 15. Therefore, the detailed description of this wheel bearing device is omitted.

[0265] In the assembled axle module of the present invention, as shown in FIG. 34, the outer diameter surface 25a of the outer member 25 of the bearing 2 is fitted and assembled to the steering knuckle 34 on the vehicle body side. The so-called fitting assembly here refers to fitting the outer member 25 to the steering knuckle 34 to complete the assembly of the two. This assembly can be performed, for example, by pressing the cylindrical outer surface 25a of the outer member 25 into the cylindrical inner peripheral surface 34a of the steering knuckle 34.

[0266] In this way, the outer diameter surface 25a of the outer member 25 constitutes a press-fit surface (knuckle fitting surface), and the outer member 25 is press-fitted into the inner peripheral surface (outer member fitting hole portion) 34a of the knuckle 34. In this case, the maximum outer diameter D12 of the constant velocity universal joint T1 is configured to be smaller than the outer diameter D11 of the knuckle fitting surface of the outer member 25, that is, the inner diameter of the outer member fitting hole of the knuckle 34. Here, the maximum outer diameter dimension D12 of the constant velocity universal joint T1 refers to the maximum outer diameter dimension of the constant velocity universal joint T1 in a state including the shield 60 and the shield band 61 and other accessories.

[0267] In this case, it is preferable to interpose a retaining ring 130 between the outer diameter surface 25a of the outer member 25 and the inner peripheral surface 34a of the steering knuckle 34. By using the retaining ring 130, the anti-separation effect of the outer member 25 and the steering knuckle 34 is improved. That is, an engagement groove 129 (refer to FIG. 15) is formed on the outer diameter surface 25 a of the outer member 25, and an engagement groove (not shown) is formed on the inner peripheral surface 34 a of the steering knuckle 34. Therefore, the retaining ring 130 engages with the engagement groove 129 of the outer diameter surface 25 a of the outer member 25 and the engagement groove of the inner peripheral surface 34 a of the steering knuckle 34.

[0268] In addition, as shown in FIG. 31, the maximum outer diameter D13 of the built-in constant velocity universal joint T2 is set to the outer diameter D11 of the knuckle fitting surface of the outer member 25, that is, the outer member of the knuckle 34 The inner diameter of the fitting hole is small. The maximum outer diameter dimension D13 of the built-in constant velocity universal joint T2 is the same as in the case of the external constant velocity universal joint T1, and refers to the state in which auxiliary products such as the shield 140 and the shield band 141 are also included. The maximum outer diameter of the built-in side constant velocity universal joint T2. In addition, the inner diameter size of the knuckle 34 is set to be substantially the same as the outer diameter D11 of the outer diameter surface 25a of the outer member 25.

[0269] The assembly of the axle module assembled in this way to the vehicle is shown in FIGS. 32 and 33. The axle module is connected from the sliding constant velocity universal joint T2 side of the built-in side at the steering knuckle 34, as shown in FIG. 34 As shown, the outer wheel bearing device

CN 101802425 Β

The outer member 25 of the steering wheel is pressed into the inner peripheral surface 34a of the steering knuckle 34. As a result, as shown in FIG. 34, in a state where the outer member 25 is pressed into the steering knuckle 34, the retaining ring 130 engages with the engagement groove 129 of the outer diameter surface 25a of the outer member 25 and the inner peripheral surface 34a of the steering knuckle 34 Slot snap.

[0270] In the axle module of the present invention, it can be assembled to a vehicle in an assembled state. As a result, it is possible to reduce work man-hours at the assembly work site and improve operability. In this case, since it is not necessary to rotate the knuckle 34 as shown in the conventional process, the working space is also sufficient at the minimum. In addition, damage to parts such as disassembly and assembly can be prevented, and the quality can be stabilized.

[0271] Therefore, the type shown in FIG. 1, the type shown in FIG. 8, the type shown in FIG. 11, the type shown in FIG. 18, the type shown in FIG. 19, the type shown in FIG. 20, the type shown in FIG. The type shown and the type shown in FIG. 23 are preferably such that the maximum outer diameter D12 of the constant velocity universal joint T1 is smaller than the inner diameter of the outer member fitting hole of the knuckle 34, which is the outer diameter D11 of the outer member 25. diameter.

[0272] In the above-mentioned embodiment, the outer member 25 of the bearing 2 does not have the body mounting flange, but the outer member 25 may have a body mounting flange 117 as shown in FIG. 35.

[0273] In the type shown in FIG. 35, the outer diameter surface 25a of the built-in side of the vehicle body mounting flange 117 in the outer member 25 constitutes a knuckle fitting surface to which the knuckle 34 is attached. Therefore, the maximum outer diameter D12 of the constant velocity universal joint T1 is smaller in diameter than the outer diameter D11 of the knuckle fitting surface. In this case, the maximum outer diameter dimension D12 of the constant velocity universal joint T1 also means the maximum outer diameter dimension of the constant velocity universal joint T1 in a state in which auxiliary products such as the shield 60 and the shield band 61 are also included. [0274] In the wheel bearing device shown in FIG. 35, a short cylindrical control portion 126 to which a wheel and a brake disc (not shown) are attached is protrudingly provided on the outer end surface of the hub wheel 1. In addition, the control section 116 is composed of a large-diameter first section 126a and a small-diameter second section 126b. The first section 126a is fitted with a brake disc, and the second section 126b is fitted with a wheel. [0275] In addition, the surface hardness of the outer root portion 127 of the wheel mounting flange 21 can be set to 35 HRC or less. That is, after the tempering treatment, the surface hardness of the external root joint 127 is set to 35 HRC or less. When the surface hardness is set to exceed 35HRC, workability such as cutting is reduced, and heat treatment deformation becomes large, the surface vibration accuracy of the brake disc mounting surface 63 of the wheel mounting flange 21 is degraded, and the increase in hardness reduces the machinability. In contrast, if the external root joint 127 When the surface hardness of the wheel is set to 35HRC or less, workability such as cutting is improved, heat treatment deformation can be suppressed, and degradation of the surface vibration accuracy of the brake disc mounting surface 113 of the wheel mounting flange 21 due to heat treatment deformation can be prevented. In addition, since the surface hardness of the bolt attachment hole 32 press-fitted into the hub bolt 33 can be close to the surface hardness of the hub bolt 33, it is possible to prevent the serration of the hub bolt 33 from collapsing and reducing the fixing force.

[0276] Above, the embodiments of the present invention have been described, but the present invention is not limited to the above-mentioned embodiments, and various modifications can be made. For example, the shape of the convex portion 35 as the concave-convex fitting structure M is shown in FIG. 2 above. In the embodiment, the cross-sectional triangular shape is a trapezoidal cross-sectional shape in the embodiment shown in FIG. 28A, but other shapes such as a semicircular shape, a semi-elliptical shape, and a rectangular shape can also be used. The area of the convex portion 35 is, The number, circumferential pitch, etc. can also be changed arbitrarily. That is, it is not necessary to form the splines 41, 111, and the convex portions (convex teeth) 41a, 111a of the spline 4Μ11 constitute the convex portion 35 of the concave-convex fitting structure Μ, which can be a structure such as a key or a wave that forms a curve. Type of antipodal surface. In short, the convex portion 35 arranged in the axial direction is pressed into the counterpart side, the concave portion 36 that is in close contact with the convex portion 35 can be formed on the counterpart side by the convex portion 35, and the convex portion 35 and the concave portion fitted with it are fitted The entire area of the joint contact portion 38 is in close contact, and it is only necessary to have a structure that can transmit a rotational torque between the hub wheel 1 and the constant velocity universal joint 3.

[0277] In addition, the hole portion 22 of the hub wheel 1 may be a polygonal hole other than a round hole or other shaped hole, and the cross-sectional shape of the end of the shaft portion 12 inserted in the hole portion 22 may be a circular cross-section. Other polygonal shapes and other special-shaped cross-sections. In addition,

CN 101802425 Β

When the shaft 12 is pressed into the hub wheel 1, it is only necessary to make the pressing start end of the convex portion 35 harder than the portion where the concave portion 36 is formed. Therefore, it is not necessary to increase the hardness of the entire convex portion 35. Although the gap 40 is formed in FIG. 2 and the like, it may be a structure in which the concave portion between the convex portions 35 bites into the inner diameter surface 37 of the hub wheel 1.

[0278] In addition, the inner diameter surface 37 of the hole 22 of the hub wheel 1 may be small recesses arranged at a predetermined pitch in the circumferential direction. As a small recess, the volume of the recess 36 needs to be smaller. By providing such small recesses, it is possible to improve the pressability of the convex portion 35. That is, by providing the small recesses, the volume of the overflow portion 45 formed when the convex portion 35 is press-fitted can be reduced, and the press-fit resistance can be reduced. In addition, the overflow portion 45 can be reduced, so the volume of the recessed portion 50 can be reduced, and the workability of the recessed portion 50 and the strength of the shaft portion 12 can be improved. In addition, the shape of the small recesses can adopt various shapes such as a triangle, a semi-elliptical circle, and a rectangle, and the number can also be set arbitrarily.

[0279] As the coupling mechanism shown in FIG. 20, a welding coupling mechanism may be used, but instead of welding, an adhesive may be used. In addition, as the rolling element 30 of the bearing 2, a roller (port 7) can be used. In addition, in the above-mentioned embodiment, the third-generation wheel bearing device is shown, but the first-generation, second-generation, or fourth-generation may also be used. In addition, when the convex portion 35 is press-fitted, the side on which the concave portion 36 is formed may be fixed and the side on which the convex portion 35 is formed may be moved. Alternatively, the side on which the convex portion 35 is formed may be fixed and moved. On one side of the recess 36, both may be moved. In addition, in the constant velocity universal joint 3, the inner ring 6 and the shaft 10 may be integrated via the concave-convex fitting structure M described in each of the above-mentioned embodiments.

[0280] In addition, in the shaft portion anti-disengagement structure M1, for example, in the case of using the retainer ring 85 shown in FIG. 19, etc., the retainer ring 85 can be provided on the shaft portion instead of being provided at the end portion of the shaft portion 12. 12 on the root side (mouth side) and so on.

[0281] In the embodiment shown in FIG. 1 and the like, a foreign body intrusion prevention mechanism W1 on the built-in side, a foreign body intrusion prevention mechanism W2 on the external side, and a foreign body intrusion prevention mechanism W3 between the fitting contact portion 38 are provided._OIt does not need to be arranged in three places like this, as long as it is arranged in at least one place. That is, it is only necessary to provide one or two of the foreign body intrusion prevention mechanisms W1, W2, and W3. Therefore, in the wheel bearing device shown in FIG. 21, the foreign matter intrusion prevention mechanism W2 is not provided, but only the foreign matter intrusion prevention mechanisms W1, W3 are provided, but in this case, the foreign matter intrusion prevention mechanism WKW3 may be omitted. Any one.

[0282] Examples

[0283] The relationship between the hardness difference between the convex portion 35 and the concave portion forming part and the press-in load was investigated, and the results are shown in FIG. 31. In this case, a male spline with a modulus of 0.48 and a number of teeth of 59 is formed on the shaft portion 12, and the male spline is pressed into the hole of the hub ring 1.

twenty two. In addition, the diameter difference between the outer diameter size of the shaft portion 12 and the inner diameter size of the hole portion 22 of the hub ring 1 is assumed to be the height of the convex portion as H. When the ratio is 4 4/211, 0.3 &lt;Ad/2h &lt;0. 86_O

[0284] From this FIG. 31, it can be seen that when the hardness difference is less than 20 HRC, the indentation load is large, and so-called cracking occurs.

[0285] Industrial availability

[0286] The first generation that can be applied to a structure that uses multiple rows of rolling bearings alone, the second generation that has a body mounting flange integrally on the outer part, and the outer periphery of the hub ring integrally having a wheel mounting flange is formed with multiple rows of rolling bearings. The third generation of the inner rolling surface on one side and the integrally formed constant velocity universal joint in the hub ring, and the outer circumference of the outer joint component constituting the constant velocity universal joint is integrally formed on the outer circumference of the multi-row rolling bearing on the other side of the inner rolling The fourth-generation multi-row rolling bearing of the surface.

CN 101802425 Β