Spherical friction ring gearbox

p0001The invention relates to a bevel friction ring gearing with at least two oppositely arranged to each other on parallel axes conical friction wheels and the two conical friction wheels operatively connected frictional device.

p0002Such conical friction wheels are known for example from <patcit id="pcit0001" dnum="DE19542726A1"><text>DE 195 42 726 A1</text></patcit> and from <patcit id="pcit0002" dnum="EP0657663A1"><text>EP 0657663 A1</text></patcit> known.

p0003It is an object of the present invention to provide a generic bevel friction ring gearing, in which the use of a finely distributed traction fluid is possible.

p0004As a solution, a bevel friction ring gearing with the features of claim 1 is proposed.

p0005Here it is particularly avoided that the bearings are used with the traction fluid in contact and be damaging in their operating characteristics. Further advantages and preferred embodiments of the present invention are explained in detail below.

p0006In one possible embodiment can be additionally adapted to the extent an inventive bevel friction ring gearing that the friction torque with a component that is perpendicular to a set by both Kegekeibachsen level acts. The friction device may be movable and designed such that it is pressed with a torque against the guide by a guide along the conical friction wheels.

p0007Such an arrangement increases the risk of flutter of friction can be minimized or reduced to "zero", since the friction of a bracing subject. In this way, an ever present guide play does not matter, because the friction creates on one side of the guide and is held by the torque applied in this position.

p0008Advantageously, the torque is due to the conical friction on the friction forces applied. In this way the friction is proportional to the applied force acting on the friction force at the lead.

p0009Such a configuration is particularly suitable for bevel friction ring gearing, in which the friction device is arranged between the conical friction wheels. This is on the one hand allows sufficient clearance for the management of friction is ensured while the friction device is stabilized. On the other hand this device allows as before, that the friction device is guided by displacement about a rotational axis along the two conical friction wheels.

p0010A specific configuration can be realized that the friction between the conical friction wheels is arranged and a first run portion which circulated at a first of the two conical friction wheels, and a second run portion which circulated at the second of the two conical friction wheels, characterized wherein the two overflow areas are arranged offset with respect to a rotating plane of the friction device. Here, the term of a barrel portion of each geometric area of ​​the friction device, which circulated on a conical friction wheel. It is understood that the transit areas may be subject to during operation of the bevel friction ring gearing a slight change. The term a plane of rotation is achieved according to a plane understood, which is arranged perpendicular to an axis of rotation of the friction device. This definition of the concept of a staggered arrangement that the two load regions differently spaced from such a plane of rotation.

p0011By such an offset arrangement of the two running regions with respect to a plane of rotation, a torque is applied to the friction device by the voltage applied to the running areas of the conical friction wheels. The guide then needs to be only configured such that this torque presses the friction against the guide.

p0012In a relatively simple structured arrangement, the friction means comprise a friction ring which comprises at least a radially outer tread and a radially inward running surface, each of the running surfaces in each case circulate in a conical friction wheel. Where the two treads arranged offset with respect to a plane of the ring, it follows an inventive torque.

p0013The friction device can be guided in a guide that includes a slide bearing between friction and leadership. Such an arrangement is surprisingly possible to ensure a smooth running of the friction ring, although no lubricant is in the generic assemblies only little or for a guided tour of the rubbing means available. It is true that such a plain comprehensive guide independently of the other characteristics of the bevel friction ring gearing advantageous calm the running of the friction device. However, the advantages of this guide cumulate with a pressed against the guide torque at a particularly smooth running of the friction device.

p0014Since the friction device is fixed by the conical friction generally, it should be sufficient to cause the friction only two implementing agencies. Surprisingly, it has been found, however, that with a guide by three implementing agencies, a roller bearing or a slide bearing, at this point provided can be a tendency to flutter substantially reduce. This is especially the case when it is the friction means is a friction ring which is arranged between the conical friction wheels. This friction ring can only rotate about its vertical axis, so that a guide should be sufficient means of one or a maximum of two implementing agencies. A tilt of the ring flutter can thereby alone does not reduce, this is the case only when three implementing agencies. Here, a reduction of the tendency to flutter already takes place independently of the other characteristics of the bevel friction ring gearing, being able to be the tendency to flutter reduced even further by acting against the leadership of torque.

p0015The friction device can be guided by a guide bar along at least one movable carriage, the carriage is performed by a ball level guidance on the guide bar. This can serve as Kugelradführung each roller guide, in which an axial guidance by means of circulating balls. In particular, find a linear bushing using. Through such storage of the carriage, which is guided in the art by means of a sliding bearing along the guide rod, the friction device and in particular a friction ring serving as friction can cause even more stable. Such an arrangement is particularly suitable for bevel friction ring gearing, in which the friction ring by displacement about a rotational axis, in particular by shifting guide rods that hold a friction ring leading carriage takes place. In such a mounting, the forces stir forth for displacement of the friction ring or the friction device of the conical friction wheels, the carriage itself is not separately driven. In such an arrangement can be ensured in this way a particularly quiet and smooth running of the friction device, especially when it is displaced along the conical friction wheels. Such an arrangement is also used independently of the other characteristics of the bevel friction ring gearing stabilize Reibeinrichtungsführung.

p0016To further stabilize this guide, at least one guide rod may be profiled. Such a measure affects not directly to the leadership of the friction out, it has been found that this measure reduces vibration may cause the overall arrangement and thus also the risk of flutter of the friction ring. Preferably, the guide rod may be I-shaped or square in profile. It is understood that such profiling also independent of a Kugelradführung of the carriage on the guide bar is advantageously used to stabilize the overall arrangement.

p0017The guide rod may be fixed to a standing frame made of sheet metal, die-cast aluminum or plastic, in particular high-performance plastic. By such an arrangement, a weight reduction is made possible. In addition, followed by a considerable simplification of the production, since an existing part of these materials need only be deformed or shaped accordingly. Although the use of such an assembly frame is also seen to be advantageous in order to achieve a corresponding reduction in weight and manufacturing cost. Particularly in connection with the ball level management as described above or a profiled guide rod to such an assembly frame proves to be advantageous, because in such an arrangement, the carriage itself to stabilize the guide rods possible so that the management of the overall arrangement is sufficiently stable in spite of the standing frame made of sheet metal.

p0018The standing frame can be driven by a linear motor or a rotary motor. This particular enables stable guidance of the friction and the fact that the friction device is only to be rotated about an axis of rotation, so they moved along the conical friction wheels, to use a motor with a relatively low power. This is particularly true for linear motors and for expensive rotary motors. Such an arrangement makes it possible to dispense with power hydraulic adjustment mechanisms whereby such a bevel friction ring gearing also builds regardless of its other characteristics cheaper.

p0019Unwanted vibrations in a generic bevel friction ring gearing can also be avoided in that at least one of the two conical friction wheels arranged on a shaft which is connected via a continuous contact area with the conical friction wheel in contact.

p0020The continuous contact area ensures a stable mounting of the conical friction wheel on the shaft, so that the risk of unwanted oscillations due to insufficient support of the conical friction wheel is reduced to the shaft. Such an arrangement makes it possible in particular to use of the conical friction wheel a less expensive and less stable material without a significant reduction in the running qualities and thus the risk of vibrations occurring.

p0021For especially small, generic Kegelreibringgetrieben both conical friction wheels can integrally comprise these trained shaft or bearing journals. This also guarantees a stable support of the conical friction wheels, so that undesired vibrations can be avoided.

p0022In such arrangements, the stability it can also continuously increased by the fact that the conical friction wheel is solid.

p0023Furthermore, allow the above-described arrangements is that a sufficiently high force can be applied to the friction device by the conical friction wheels in order to ensure a sufficient power transmission.

p0024It is in particular also possible to form one of the conical friction wheels of steel. This not only ensures a favorable intrinsic elasticity of the conical friction wheel when it interacts with the friction device. On the other hand steel is relatively inexpensive. The required stability can be ensured by the foregoing configuration variations. However, it goes on the other hand, that a conical friction wheel made of steel is also independent of the other characteristics of the bevel friction ring gearing advantageous.

p0025In contrast, the friction device having a ceramic surface. This advantageous friction between the conical friction wheels and the friction device can be ensured in a cost effective manner. In particular, the friction device may comprise a friction ring made of ceramic.

p0026Particularly in connection with the above-described arrangement, a traction fluid can be provided, which is responsible for the friction between the friction device and substantially conical friction wheels. That is, the traction fluid is selected such that the friction between the friction device and conical friction wheels is much greater when using the traction fluid than without. In particular, the traction fluid diamond powder or other solid particles may comprise. The use of such a traction fluid is also independent of the other characteristics of the bevel friction ring gearing advantageous.

p0027According to the camp of the conical friction wheels are sealed against surrounding the conical friction area. This avoids that the bearings are used with the traction fluid in contact and be damaging in their operating characteristics. Such an arrangement allows the use of a traction fluid which is free in the space surrounding the conical friction around splash the first time. So it is by such an arrangement for the first time possible to provide a traction fluid sump at the bottom of the conical friction surrounding area and to ensure a distribution of the traction fluid by the rotational movement of the lower, diving in the traction fluid sump conical friction wheel. The known arrangements precluded the use of such, is finely distributed traction fluid not.

p0028Furthermore, by sealing the Kegelreibradlager against surrounding the conical friction area, which are subjected to a plurality of bearing a common lubrication.

p0029In this respect the provided on one side of the Kegelreibradraumes bearings may be arranged in interconnected warehouses. The joint lubrication is then achieved by the combination of these storerooms. It is understood that these storage areas may also be part of a larger, provided next to the Kegelreibradraum space.

p0030Likewise, at least two provided on different sides of the Kegelreibradraumes bearings may be arranged in interconnected warehouses. This can be done by appropriate lubricant lines.

p0031Overall, it is possible in this way to provide a lubrication circuit for all, the conical friction bearings in stock. This arrangement makes it possible in particular, in contrast to the known Kegelreibringgetrieben to use a lubricant selected specifically for the stock, which can be selected independently of the next in the Kegelreibradraum used fluid.

p0032It is understood that such a configuration of the storage rooms is also independent of the use of a traction fluid or independently of the other characteristics of the bevel friction ring gearing advantageous.

p0033The arrangement described above with shared storage spaces proves to be particularly advantageous if the bevel friction ring gearing comprises at least one taper roller bearing. It is known that produce tapered roller bearings for truncated cone toward a positive pressure which is so great that on this side of the sealing of the tapered roller bearing can not be provided because such a seal is forced open by the pressure generated there.

p0034But if one sees between this seal and the tapered roller bearings from a staging area, from which emanates at least one lubricant feed line to another camp, this pressure may serve a conveyance of the lubricant.

p0035In this way, a lubrication circuit can be realized, which makes do without an additional lubricant pump or the like.

p0036For cone apex of the tapered roller bearing toward a lubricant sump may be provided in addition, from which promotes the tapered roller bearing lubricant. This lubricant sump can be connected to a corresponding return line from another camp.

p0037The use of a tapered roller bearing to lubricant delivery, in particular to other camps a mechanical arrangement is also independent of all the foregoing features advantageously applicable. This ensures a particularly reliable lubricant supply is ensured in particular, which is structurally very simple to implement.

p0038At least one conical friction wheel may have a spherical roller bearing. Thereby, the smoothness and the light transmitted through the bevel friction ring gearing torque can be increased, since such storage makes it possible to charge the two conical friction wheels and the friction device to a bending of the conical friction wheels or the conical friction overlapping waves. Even under such a high load to ensure safe and smooth running of the bevel friction ring gearing can be ensured.

p0039In addition, at least one conical friction wheel to be mounted by means of an axially acting bearing, which is arranged to be movable in the radial direction. By thus bearing very high axial forces can be absorbed, the bearing of a shaft deflection can be followed by the movability in the radial direction. As such bearings Axial angular contact ball bearings, cylindrical roller bearings, thrust ball bearings, axial needle roller bearings are also ball groove bearings and angular contact ball bearings in question, which are assembled with a corresponding radial clearance. this can also be used a tapered roller bearing of the type described above.

p0040It is in particular also possible to provide this axially acting bearings on the same side of the conical friction wheel as a spherical roller bearing. So the warehouse tasks can be distributed according to both camps.

p0041It can hydraulic means may be provided which ostensive at least one conical friction wheel with an axially directed, preferably from the truncated cone to cone tip, can apply force. By such an arrangement, the tension between the conical friction wheels and friction can be controlled in a structurally simple manner. This can happen in particular in dependence on a load, but also in dependence on a selected acceleration or velocity.

p0042Such hydraulic adjustment is much more flexible than previously known, mechanical adjustments.

p0043The hydraulic means may in particular comprise a in the axial direction with respect to the conical friction wheel adjustable punch which acts on a corresponding bearing of the conical friction wheel. It is also possible to provide mechanical means, which allow a force loading. In particular, this disc springs can be engaged in an axial biasing force on the conical friction wheel or on the cylinder described above.

p0044The invention further provides a method for controlling the transmission ratio in a bevel gear, wherein the gear ratio in dependence upon a relative position of a rotating friction element can be adjusted and the friction element by varying a rotational position about an axis in its relative position can be changed, ready to said rotational position the friction element is used as an actuator for the control. This can be guaranteed a very precise and smooth-running control of the transmission ratio.

p0045The rotational position of the friction element can be changed, for example, by rotating the framework described above and the guide rods described above. For this purpose, as also described above, find an engine use.

p0046To increase the control accuracy, the rotational position of the friction element can be determined and used for control. This is preferably done by using the estimated rotational position as the control number, so that these detected rotational position is only indirectly used for control.

p0047Similarly, the relative position of the friction element can be determined with respect to the cone and used for control. This is also done preferably as the control number. However, the determined relative position of the friction element can also be used directly to control especially in fast adjustment procedures.

p0048Through the above-described regulatory procedure, a particularly smooth running of the bevel gear can be ensured. Such a designed control loop can be mastered relatively well in its vibration behavior.

p0049As controlled variable speed ratio between an input-side shaft and an output-side shaft of the bevel gear can be controlled. Such control variable is relatively easy to identify; This can be done by two correspondingly arranged tachometer.

p0050The above-described methods and arrangements are any, to improve the smoothness of a bevel gear or a bevel friction ring gearing. Here, the features described above can either individually or independently improve smoothness. However, the combination of individual features provides surprising improvements in such transmissions, which would not be expected at a mere feature addition.

p0051Further advantages, objects and features of the present invention will become apparent from subsequently explained with reference to the drawing appended embodiments. In the drawings:<dl id="dl0001" compact="compact"><dt>figure 1</dt><dd>a bevel friction ring gearing in section;</dd><dt>figure 2</dt><dd>the bevel friction ring gearing according <figref idrefs="f0001">figure 1</figref> along the line II-TI in <figref idrefs="f0001">figure 1</figref>; </dd><dt>figure 3</dt><dd>the bevel friction ring gearing according <figref idrefs="f0001">figure 1</figref> taken along the line III-III in <figref idrefs="f0001">figure 1</figref>;</dd><dt>figure 4</dt><dd>a side view of a guide block and a run in this guide carriage friction ring for the bevel friction ring gearing according <figref idrefs="f0001">figure 1</figref>;</dd><dt>figure 5</dt><dd>a section through the friction ring and its guide carriage by <figref idrefs="f0003">figure 4</figref> taken along the line VV in <figref idrefs="f0003">figure 4</figref>;</dd><dt>figure 6</dt><dd>a section through the friction ring and its guide carriage by <figref idrefs="f0003">figure 4</figref> along the line VI-VI in <figref idrefs="f0003">figure 4</figref>;</dd><dt>figure 7</dt><dd>a section through an assembly frame of Kegelreibring-gearbox after <figref idrefs="f0001">figure 1</figref> taken along the line VII-VII in <figref idrefs="f0001">figure 1</figref>;</dd><dt>figure 8</dt><dd>a schematic sectional view of the two conical friction wheels arranged between the friction ring of the bevel friction ring gearing according to <figref idrefs="f0001">figure 1</figref>; and</dd><dt>figure 9</dt><dd>a section through another bevel friction ring gearing in a similar representation to <figref idrefs="f0001">figure 1</figref>,</dd></dl>

p0052In the Kegelreibringgetrieben shown in the drawing two conical friction wheels 2, 3 to each other are arranged on parallel axes in a housing 1 opposite. The two conical friction wheels 2, 3 are operatively connected by a friction ring serving as a friction device 4th This friction ring 4 rotates between the two conical friction wheels 2, 3 and communicating with the outer surfaces of these two conical friction wheels 2, 3 in contact.

p0053The friction ring 4 is mounted in a guide 5 and displaced by means of this guide. 5 These guide 5 comprises a carriage 50 which is guided on two guide rods 51st While, as from<figref idrefs="f0003">figure 6</figref> visible, the carriage 50 of the first bevel friction ring gearing is guided in a sliding guide on the guide rods 51, this guidance takes place at the in <figref idrefs="f0005">figure 9</figref> Illustrated embodiment, by a ball socket 54. The guide rod of the in <figref idrefs="f0005">figure 9</figref> Bevel friction ring gearing shown is profiled square.

p0054The two guide rods 51 of both bevel friction ring gearing are fixed on a standing frame 52nd During the assembly frame 52 of the in<figref idrefs="f0005">figure 9</figref> Bevel friction ring gearing shown is connected directly to the guide rods 51, this connection is made in which, in <figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing shown indirectly via a stabilizing compound bow 55 (see <figref idrefs="f0003">figure 7</figref>).

p0055The assembly frame is displaceably mounted around a rotation axis 53 on the housing first The transfer takes place at the in<figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing illustrated by means of a rotary motor 56 ', during the assembly frame 52 wherein in <figref idrefs="f0005">figure 9</figref> Bevel friction ring gearing shown is driven by a linear motor 56 '.

p0056In the in <figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing shown, the guidance of the friction ring by provided on two implementing agencies roller pairs 57 (see in particular <figref idrefs="f0002 f0003">Figures 2 to 5</figref>). In the bevel friction ring gearing according<figref idrefs="f0005">figure 9</figref> other hand, is guided in a slide guide 58 of the friction ring. 4 As is immediately apparent, instead of the two implementing agencies (see<figref idrefs="f0003">figure 4</figref> or. <figref idrefs="f0005">figure 9</figref>be provided) and several implementing agencies.

p0057The two friction rings 4 of the two bevel friction ring gearing shown rotate about an axis which is aligned parallel to the axes of the conical friction wheels 2, the third It is possible to arrange the axis also at an angle thereto. In particular, the axis can also be provided in parallel to the lateral surfaces. Accordingly, the friction rings 4 rotate in a rotational plane, which is perpendicular to this axis of rotation. In the schematic representation according to<figref idrefs="f0004">figure 8</figref> is exemplified as the plane of rotation 40, such plane of rotation. Likewise, this level is 40 for a ring plane.

p0058As from <figref idrefs="f0004">figure 8</figref> be seen, the friction ring know 4 has two running portions or treads 41, 42, with which it rolls in each case on one of the conical friction wheels 2, the third As<figref idrefs="f0004">figure 8</figref> shows the two running surfaces 41, 42 offset with respect to the plane 6 are arranged. By such an arrangement, a torque is exerted on the friction ring by the two conical friction wheels 2, the third

p0059Due to its symmetry of the friction ring 4 can be changed substantially only about its vertical axis in its position. In addition, a slight tilting is possible.

p0060The force acting on the friction ring 4 torque is selected so that it acted on the friction ring 4 even in the latter direction with a force. Here by the friction ring 4 is pressed against the guide. 5 It is otherwise also possible to load the friction ring 4 with an opposite torque.

p0061The prescribed torque and sufficient frictional force between the conical friction wheels 2, 3 and the friction ring 4 is ensured that the conical friction wheels 2, 3 are axially braced against one another. To address this tension, the two conical friction wheels 2, 3 of the in<figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing shown arranged on a shaft 20, 30, 31 which are connected via a substantially continuous contact area 21, each with the conical friction wheels 2, 3 in contact. The two conical friction wheels 2, 3 of this bevel friction ring gearing are otherwise carried out massively.

p0062To the stability of a cavity comprehensive conical friction wheels 2, 3 of the in <figref idrefs="f0005">figure 9</figref> increase bevel friction ring gearing shown, this can have one piece with these trained shaft or bearing journals. Likewise, a massive formation of conical friction wheels 2, 3 is possible.

p0063The conical friction wheels 2, 3 both Kegelreibradgetriebe are formed of steel. The friction ring 4 is made of a ceramic. The bottom of the housing 1, a sump is provided from traction fluid. The traction fluid can be mixed with diamond powder. The amount of traction fluid is such that a lower portion of the friction wheel 3 is immersed in this swamp and an equilibrium in the operation of the bevel friction ring gearing between the distributed in the casing 1 traction fluid and the fluid in the sump traction.

p0064The conical friction wheels 2, 3 are mounted by means of bearings 22, 23 and 32, 33rd The bearings 22, 23 and 32, 33 are each in sealed storerooms, so that in particular no traction fluid in these storage rooms or on these bearings 22, 23 and 32, 33 passes. All storage rooms are connected by a lubricant line, which circulates through bearing oil. In the in<figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing shown is this circulation maintained by an oil pump, during this at the in <figref idrefs="f0005">figure 9</figref> Bevel friction ring gearing shown is carried through the bearings 23 and 33rd The latter bearings are designed as tapered roller bearings. For cone apex of the tapered roller bearing 33, a bearing oil sump 34 is provided, while on the truncated cone of the bearing 33 is a staging area 35, in which the bearing oil is pumped from the tapered roller bearing 33rd From the collecting chamber 35 to go stock oil lines to the other camps.

p0065All bearings 22, 23 and 32, 33 refer to the radial forces. However, the bearings 23 and 33 also serve to absorb axial forces. This is according to the bevel friction ring gearing at<figref idrefs="f0005">figure 9</figref> by the tapered roller bearings 23 and 33 which are arranged opposite accordingly ensured. This bevel friction ring gearing bearings 22 and 32 are designed as cylindrical roller bearings.

p0066By contrast, the axial forces on the bearings 23 and 33 of in <figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing compensated by a combination of spherical roller bearings and deep groove ball bearings shown. The bearings 23 and 33 are arranged for this purpose on different sides of the bevel friction ring gearing. Actually uses the spherical roller bearings Low radial and axial forces. It is particularly useful to follow a bending of the shafts 20 and 30 respectively. The Roller bearings on the other hand is primarily made for supporting axial loads and can be moved radially in the housing. 1

p0067In order to ensure the necessary axial tension, the two bevel friction ring gearing each have a clamping device, through which the conical friction wheel can be subjected to an axially directed, by the truncated cone to cone tip pointing power. For this purpose, in which in<figref idrefs="f0005">figure 9</figref> illustrated bevel friction ring gearing a plate spring arrangement and a helical cam clutch provided. The ramp cam clutch allows torque adjustment, while the disc spring assembly requires a base load. The ramp cam coupling includes radially extending bevels that accrue under a force acting on the conical friction wheel 3 successive torque, thereby increasing the contact pressure. In the in<figref idrefs="f0001 f0002 f0003">Figures 1-7</figref> Bevel friction ring gearing shown this are hydraulic means provided 36th Here is an axially movable cylinder 37, which can be driven hydraulically via an opening 38 and acts on the deep groove ball bearings of the bearing 33rd

p0068The control of the ratio of the two bevel friction ring gearing is effected by tachometer 30 are provided on both the drive shaft 20 as well as on the output shaft. As controlled variable speed ratio is used between the two shafts 20, 30. The speed ratio is controlled by the rotational position of the friction ring. 4 This rotational position, by the motors 56 'and 56 "are changed. Attempting the speed ratio of the desired speed ratio, is a corresponding change in position by the motors 56' and 56" generates. Then, the friction ring travels along the lateral surface of the conical friction wheels 2, 3. the desired speed ratio is reached, an appropriate rotational position change of the friction ring 4 is made and this aligned parallel to the Kegelreibradachsen.

p0069The rotational position of the friction ring 4 is determined by the position of the motors 56 'and 56 "and used as a control variable.

p0070Furthermore, the relative position of the friction ring 4 is determined. The measured relative position is also one as a control element in the control loop. This is made 4 use of the relative position only in the case of relatively rapid displacement of the friction ring.