Occupant restraint device and power generating device

INDUSTRIAL APPLICABILITY The present invention is an occupant restraint device and the device attached to a vehicle seat device in order to prevent an occupant from slipping forward from the lower part of the seat belt when an impact such as a vehicle collision occurs. It relates to a power generator for instantaneously driving a driven member suitable for use in a high-speed operation mechanism such as the above.

[0002] Conventionally, there is a so-called submarine phenomenon in which an occupant slides forward from the lower part of a seatbelt and the waist belt comes off from the pelvis portion when an impact such as a vehicle collision occurs. This submarine phenomenon is likely to occur when the occupant is sitting shallowly on the seat or the seat back is tilted down, and in some cases, the occupant restraint effect of the seat belt may be reduced, or the occupant restraint part may shift. there were.

[0003] For example, it is conceivable to provide a protrusion on the front end of the seat frame or to raise the front end by providing a panel to prevent the submarine phenomenon, but if the protrusion or the panel is too low, a sufficient effect cannot be obtained. However, if it is raised, there is a drawback that a foreign body sensation is generated during normal use and the ride is uncomfortable.

[0004] Therefore, in order to raise the front end of the sheet only when an impact is generated, an airbag is used (for example, Japanese Patent Application Laid-Open No. 5-229378, Japanese Patent Application Laid-Open No. 7-81466, Japanese Patent Application Laid-Open No. 3-227745, etc.). ), The one that mechanically lifts the tip of the sheet (see Jitsukaihei 2-149328, Jitsukaihei 3-121947, Jitsukaihei 4-93222, etc.), and the high pressure generated by a chemical reaction as a power generator. There is a device that mechanically lifts the tip of the sheet using gas (see Japanese Patent Application Laid-Open No. 3-61440).

[0005] FIG. 15 shows a power generator 50 using a conventional high-pressure gas. An inner hole 51a having a reduced diameter portion 51b is formed in the middle portion of the cylinder 51 fixed to the base member of the seat, and the piston 52 is received in the one end side portion thereof. For example, the free end portion 52a of the piston 52 integrally held in the main body portion by screwing protrudes from one end opening of the cylinder 51 and engages with the seat tip portion via a link member or the like, and the base end portion 52b The diameter is slightly increased, and it is in contact with the inner peripheral surface of the cylinder 51 via an O-ring 53. A cap 54 having an opening 54a in the center is fastened to one end opening of the cylinder 51. This opening 54a slides in contact with the intermediate portion of the piston 52 and functions as a bearing when the piston 52 moves.

[0006] Further, the gas generator 55 is received in the other end side portion of the inner hole 51a of the cylinder 51. The rear end opening of the cylinder 51 is crimped via a holding plate 57 that also serves as a seal to prevent the gas generator 55 from coming off.

[0007] [Problem to be Solved by the Invention] In the above structure, the piston 52 is assembled in a state of being most immersed in the inner hole 51a of the cylinder 51, but the base end portion 52b of the piston 52 and the stepped portion of the reduced diameter portion 51b If the gap between the two is small, it cannot be absorbed if the dimensional error of the device component (for example, the connecting part of the link member, the base member of the seat and the cylinder receiving part), or the misalignment of the link member at the time of assembly is large. There was a problem that it became difficult to assemble. Further, if there is a backlash in the connecting portion between the free end portion 52a of the piston 52 and the link member or the like or the connecting portion between the link member or the like and the seat tip portion after assembly, the so-called billiards are formed at the portion having the backlash during operation. A phenomenon occurs, and the impact force causes local plastic deformation in each part, resulting in energy loss of high-pressure gas.

[0008] On the other hand, in order to prevent the occupant from being thrown forward in the event of a collision or the like, a buckle to which a seatbelt for restraining the movement of the occupant is fastened is rapidly attached to the seat of the automobile. A pretensioner device has been proposed in which the seatbelt is moved in a direction to increase the binding force of the seatbelt (see US Pat. No. 4,705,296, etc.).

[0009] As such a pretensioner device, for example, as described in Japanese Patent Application Laid-Open No. 10-181529, a power generator using a high-pressure gas generated by a chemical reaction to pull a buckle is used. There are some, but there is a problem that rattling occurs in the same way as above.

[0010] Therefore, it is advisable to incorporate a structure that absorbs this backlash into each device, but there is a problem that the device becomes large depending on the structure.

[0011] The present invention has been devised to solve the problems imposed on the prior art, and the object thereof is high operational reliability, easy assembly, and further miniaturization. It is an object of the present invention to provide a occupant restraint device and a power generator suitable for use in these high-speed operation mechanisms.

[Means for Solving the Problems] In order to achieve the above object, in the present invention, in order to prevent the occupant from slipping forward from the lower part of the seat belt when an impact such as a vehicle collision occurs, the seat is seated at the time of impact. A slip-out prevention member movably supported by a casing fixed to a frame so as to project upward is projected upward by a power generator and is received in a cylinder in a occupant restraint device held by a lock mechanism at that position. At the same time, a power generator having a structure in which a piston member whose one end directly or indirectly engages with a slip-out prevention member is projected by a gas generating means for rapidly increasing the internal pressure of the cylinder is used, and the piston member is attached with a spring in the protruding direction. Force<u style="single">Then, let the tip of the gas generating means enter the central through hole of the spring.</u>The structure was set.

[0013] Further, a piston member that directly or indirectly engages with the driven member is received in a cylinder fixed to drive the driven member instantaneously, and the gas generating means also received in the cylinder is used. This piston is supported by a step portion provided in the cylinder in the cylinder in the power generator in which the internal pressure of the cylinder is rapidly increased to move the piston member in the protruding direction, and the piston member is urged in the protruding direction. A spring arranged between the member and the gas generating means is provided, and the tip of the gas generating means is made to enter the central through hole of the spring.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0015] FIG. 1 shows a perspective view of a vehicle seat 1 according to a first embodiment to which the present invention is applied. FIG. 2 is a side view of the partial fracture. The seat frame 3 slidably supported in the front-rear direction on the seat rail 2 of the vehicle seat 1 fixed to the vehicle body can be fixed at a desired position by a seat adjuster mechanism (not shown). A pair of sub-assemblies 4 constituting the occupant restraint device are symmetrically fastened to the seat frame 3.

FIG. 3 shows the configuration of the sub-assembly 4 of the occupant restraint device. Since the left and right sub-assemblies 4 have the same structure, only one on the right side when facing the front of the vehicle will be described, and the illustration and detailed description of the other will be omitted. The sub-assembly 4 of the occupant restraint device consists of a rectangular tubular casing 5, an arm 6 rotatably supported by a collar 6a on the casing 5 with a support portion 5d, and both arms 6 at both ends thereof. Near the operating end of the power generator 8 and the power generator 8 received in the casing 5 to drive the slip prevention member 7 which is engaged and forms a bar shape, and the slip prevention member 7 is driven via the arm 6. It is composed of a one-way lock mechanism 9 supported by the casing 5 and a slip-out prevention member protrusion start load defining means 10 (FIGS. 4 and 6) attached to the one-way lock mechanism 9. By engaging the pin 12 attached to the free end of the piston rod 11b of the piston member 11 described later with the elongated hole 6b provided at a position offset from the support portion 5d of the arm 6, the piston The free end portion of the rod 11b is connected to a position offset from the support portion 5d of the arm 6. Further, the pin 12 is guided by the guide hole 5c in the direction of appearance of the piston rod 11b formed in the casing 5. The power generator 8 and the one-way lock mechanism 9 are fixed and held in the casing 5 by receiving them into the main body 5a of the casing 5 and then crimping the lid 5b. The collar 6a and the pin 12 are prevented from coming off by crimping and widening the tip portion thereof.

As shown in FIG. 4, the power generator 8 includes a cylinder 13 fixed to the seat frame 3 via a casing 5 and a piston body 11a movably received in the inner hole 13a of the cylinder 13. And a gas generator 14 as a gas generating means received on the proximal end side of the piston body 11a. An elastic sealing member 15 and a compression coil spring 16 are interposed between the piston body 11a and the gas generator 14, and the piston body 11a is constantly urged in the operating direction (protruding direction). The seal member 15 may be elastic as long as it has elasticity in the axial direction and can reliably prevent leakage when gas is generated.

[0018] Here, the gas generator 14 has a base end measuring large diameter portion 14a and a tip side small diameter portion 14b from which gas is ejected, and a step portion 14c between the step portion 14c is interposed via an annular sealing member 15 having elasticity. It abuts and engages with the stepped portion 13b formed on the cylinder 13 and enters the central through hole of the compression coil spring 16 through the central through hole of the seal member 15. Further, the step portion 14c forms a spring seat of the compression coil spring 16 via the seal member 15. The small diameter portion 14b on the tip side of the gas generator 14 has a gap in the central through hole of the compression coil spring 16 between the piston body 11a and the tip of the small diameter portion 14b on the tip side of the gas generator 14 even at the time of maximum contraction. It's getting into the level of securing. As a result, even if an external force is generated to move the piston body 11a to the gas generator 14 side during or after assembly, there is no concern that the piston body 11a will hit the tip of the small diameter portion 14b on the tip side of the gas generator 14. It is possible to prevent damage and deformation of the gas generator 14. Further, the small diameter portion 14b on the tip side of the gas generator 14 also fills the inner hole of the step portion 13b of the cylinder 13, and further rushes into the compression coil spring 16 to fill the dead space, so that the dead space can be filled when gas is generated. The initial volume can be reduced, that is, the amount of propellant used for the gas generator 14 can be reduced.

[0019] The piston body 11a is in contact with the wall surface of the inner hole 13a via an O-ring 17. Further, a piston rod 11b whose free end portion is coupled to the arm 6 abuts on the piston body 11a from the axial direction, and the piston member 11 is composed of the piston body 11a and the piston rod 11b. Here, the piston body 11a and the piston rod 11b form a curved surface shape having a curvature toward the center of the axis, for example, a spherical concave portion and a curved surface shape having a slightly smaller curvature, for example, a spherical convex portion. Engagement (contact) by contacting at the central part, which automatically aligns the two, prevents the piston rod 11b from twisting in the cylinder 13, and is concerned about gas leakage due to energy loss and eccentricity. There is no.

[0020] Actually, as shown in FIG. 5, the piston body 11a and the piston rod 11b have a tapered recess that gradually reduces in diameter toward the center of the axis, and the diameter is slightly smaller than this taper. It may be engaged by contact with the tapered convex portion at the central portion. Further, the concave portion may be tapered and the convex portion may be curved.

[0021] Further, as described above, the compression coil spring 16 constantly urges the piston body 11a in the operating direction, so that the piston rod 11b is also urged in the operating direction, and the piston rod 11b and the arm 6 are connected to each other. The backlash of the part etc. is absorbed. The spring is not limited to the compression coil spring, and may be a disc spring or a rubber elastic body. The diameter of the working end opening 13c of the cylinder 13 is reduced so that the outer peripheral surface of the intermediate portion of the piston rod 11b is in sliding contact with the opening 13c.

[0022] In order to assemble the power generator 8, first, the piston body 11a and the compression coil spring 16 are inserted from the side opposite to the operating end opening 13c of the cylinder 13, that is, the base end side opening, and further, the seal member 15 is assembled. And the gas generator 14 is inserted and the opening portion on the base end side of the cylinder 13 is crimped via the holding plate. Since the assembly direction can be unified in this way, and the caulking is sufficient at one opening on the base end side of the cylinder 13, the ease of assembly is improved. At this time, the elastic sealing member 15 is interposed between the step portion 13b of the cylinder 13 and the step portion 14c of the gas generator 14, so that the dimension A of the gas generator 14, the caulking dimension B of the cylinder 13 and the like are formed. Even if it fluctuates, it can be absorbed by the elastic deformation of the seal member 15, so that there is no problem such as damage or deformation of the gas generator 14 even if it is caulked.

At this point, the piston rod 11b is not assembled to the power generator 8, and if it is treated as a separate part, even if the gas generator 14 is activated for some reason, the piston body 11a is contained in the cylinder 13. Is easy to handle because it only moves. Further, since the piston body 11a is light, it is not necessary to provide a strong cap on the operating end opening 13c of the cylinder 13, and since the opening only needs to be reduced in diameter, it is not bulky in the radial direction and is lightweight. .. This makes it possible to further reduce the size and thickness of the occupant restraint device, and improve the degree of freedom in arranging the device and the ease of assembly. Further, since the cutting process for providing the cap is not required, the ease of manufacturing the cylinder is improved.

[0024] A one-way lock mechanism 9 is provided at the tip of the power generator 8. The one-way lock mechanism 9 has a plurality of engaging pieces 19 surrounding the outer periphery of the piston rod 11b and these engaging pieces 19 inside the casing 18 fixed to the casing 5 so as to cover the outer periphery of the piston member 11. It has a structure that receives the spring 20 that urges the base end side of the piston member 11, that is, the cylinder 13 side. The outer peripheral surface of each engaging piece 19 is gradually reduced in diameter from the free end side to the base end side of the piston member 11. Further, the inside of the casing 18 is composed of a tapered portion 18b that gradually narrows from the large diameter portion 18a. Therefore, in the state of FIG. 4, each engaging piece 19 is urged by the spring 20, pressed by the tapered portion 18b, and is in contact with the outer peripheral surface of the piston member 11, but moves in the direction in which the piston member 11 protrudes. At that time, each engaging piece 19 also moves in the direction in which the piston member 11 protrudes against the urging force of the spring 20, reaches the large diameter portion 18a, and separates from the piston member 11, so that the piston member 11 moves freely. .. On the contrary, when the piston member 11 is moved in the immersive direction, each engaging piece 19 moves to the tapered portion 18b due to the urging force of the spring 20 and comes into contact with the outer peripheral surface of the piston member 11 to fix them. It has become. Here, an annular groove or a threaded groove 11c is formed on the outer peripheral surface of the piston rod 11b. An annular groove or a threaded groove 11c corresponding to the groove 11c is also formed on the inner peripheral surface of each engaging piece 19. Therefore, when trying to move the piston member 11 in the immersive direction, the inner peripheral surface of each engaging piece 19 and the outer peripheral surface of the piston member 11 engage with each other, and both are firmly fixed at that position. It has become.

[0025] At the tip of the one-way lock mechanism 9, a slip-out prevention member protrusion start load defining means 10 forming a lid of the casing 18 is provided. The slip-out prevention member protrusion start load defining means 10 is fitted to the tip end portion of the casing 18, and is fixed by engaging the engaging portion 10a of the slip-out prevention member protrusion start load defining means 10 in the engaging groove 18c. ing. An opening 10b having an annular groove or a threaded groove with which the groove 11c of the piston rod 11b is engaged is formed in the central portion of the slip-out prevention member protrusion start load defining means 10. Further, a thin portion 10c is formed around the opening 10b. As a result, even if the piston member 11 tries to move in the protruding direction in a normal state, the inner peripheral surface of the opening 10b and the annular groove or the threaded groove 11c on the outer peripheral surface of the piston member 11 are engaged with each other. It is designed to hold. However, when a load larger than a predetermined load, that is, a thrust force by the gas generator 14, is applied, the thin-walled portion 10c is destroyed and the piston member 11 protrudes. Further, the piston member 11 does not come off even when the sub-assembly 4 is transported before assembling, and the ease of handling thereof is improved.

[0026] The left and right arms 6 are firmly connected to each other by a slip-out prevention member 7 extending in the left-right direction of the vehicle. The sub-assembly 4 of each occupant restraint device is bolted to the seat frame 3 at the support portion 5d and the fastening portion 5e.

[0027] The occupant restraint device is composed of the sub-assembly 4 of the left and right occupant restraint devices, and the impact generation detecting means and the control means including an acceleration sensor (not shown) .

[0028] The occupant restraint device can be assembled to the existing seat even when the seat is assembled. However, for example, when the seat is assembled at the same time as welding or the like, the welding process is completed. After that, it is advisable to assemble the sub-assembly 4 of the occupant restraint device having the power generator 8 with the built-in explosive. Further, in this configuration, the seat frame 3 is attached to the seat rail 2 via a slideable holder, but in the case of a tiltable or liftable seat, it is attached to the assembling bracket.

[0029] Next, the operation procedure of the present embodiment will be described. First, during normal running, since the inner peripheral surface of the opening 10b and the thread groove 11c on the outer peripheral surface of the piston member 11 are engaged as described above, the piston member 11 and the arm 6 and the arm 6 engaged with the thread groove 11c are engaged. The slip-out prevention member 7 does not move carelessly and holds its position. Then, when an impact such as a collision is detected by a sensor or the like (not shown), gas is generated in the gas generator 14, and the internal pressure of the cylinder 13 rapidly increases, so that a thrust force is generated in the protruding direction of the piston member 11. Then, the load is input to the opening 10c of the slip-out prevention member protrusion start load defining means 10 which is engaged with the annular groove or the thread groove 11c on the free end side of the piston member 11, that is, the free end side of the piston rod 11b. , The thin portion 10d is destroyed, and the free end side of the piston member 11 instantly protrudes from the cylinder 13. Then, the arm 6 connected to the free end of the piston rod 11b rotates clockwise as shown by the imaginary line in FIG. 2, and the slip-out prevention member 7 moves (protrudes) upward, and in some cases, the seat cushion is pushed. It will swell and prevent the occupant's submarine phenomenon. Even if the gas generation by the gas generator 14 ends and the driving force of the power generator 8 disappears, the one-way lock mechanism 9 prevents the slip-out prevention member 7 that has moved upward from returning downward, and the effect of preventing the submarine phenomenon is maintained. To do.

[0030] In this configuration, the same one-way lock mechanism is provided on both the left and right sides to hold both sides against the load from the occupant, but only one can be used as long as the strength can be secured. At that time, the one-way lock mechanism is different on the left and right sides. You may use the kind. For example, the one-way lock device may be provided on one side, and a ball one-way lock device or the like that can be locked at a stepless position may be provided on the other side. Similarly, if power generators are provided on both the left and right sides, one power generator can be miniaturized, and the devices are distributed on both sides of the seat, which has the advantage of not locally increasing the size, but the required power is required. If it can be obtained, only one of them may be used.

FIG. 7 shows a perspective view of a vehicle seat incorporating a seatbelt pretensioner device according to a second embodiment to which the present invention has been applied. In FIG. 7, the seatbelt 23 pulled upward from the ELR device 22 fixed to the lower part of the center pillar 21 in the vehicle interior passes through the through ring 24 attached to the upper part of the center pillar 21 and then extends downward. The end 26 is fixed to the rear side surface of the seat 25. A tongue plate 27 is provided in the portion of the seatbelt 23 between the through ring 24 and the end portion 26 so as to be movable along the seatbelt 23. Further, a buckle 28 is attached to the side surface of the seat opposite to the fixing point of the seat belt end portion 26 via the pretensioner device P.

[0032] The occupant seated on the seat 25 pulls out the seat belt 23 from the ELR device 22 and connects the tongue plate 27 to the buckle 28, whereby the seat belt 23 is hung from the occupant's shoulders to the chest and around the waist. ..

[0033] The pretensioner device P is for automatically increasing the tension force of the seat belt 23 in the event of a vehicle collision or the like, and as shown in FIGS. 8 and 9, the entire device is mounted on the side surface of the seat 25. A base plate 31 for fixing, an arm 32 having one end pivotally attached to the base plate 31 and the other end connected to an anchor portion 28a of the buckle 28, and a power generator according to the present invention substantially fixed to the base plate 31. 8 and a link member 34 having one end connected to the operating end of the power generator 8 and the other end connected to a position at an appropriate radial distance from the pivoting center on the pivoting end side of the arm 32. , A one-way lock mechanism 35 including a known ball one-way lock mechanism or the like for defining the rotation direction of the arm 32 to only one side.

A center shaft 36 that supports the arm 32 is attached to the base plate 31. One end of the arm 32 is rotatably fixed to the center shaft 36, and the anchor pin 37 is fixed to the other end by projection welding or the like. The anchor portion 28a of the buckle 28 is rotatably supported by a protruding portion from the side surface of the arm 32 of the anchor pin 37.

One end of the link member 34 is rotatably connected to the operating end of the power generator 8 as in the first embodiment, that is, the free end portion of the piston rod 11b, and the vicinity of the other end is relative to the arm 32. It is rotatably connected. Further, the C-shaped portion 34a at the other end of the link member 34 is engaged with the pin 38 to form a fuse to prevent the arm 32 from being inadvertently rotated.

[0036] Here, in the present embodiment, the one-way lock mechanism 35 and the fuse (C-shaped portion 34a, pin 38) are separately provided. Therefore, as shown in FIG. 10, the power generator 8 has the one-way lock mechanism 9 and the fuse (C-shaped portion 34a, pin 38). (Slip prevention member) The protrusion start load regulating means 10 is not provided, but conversely, the power generator 8 is provided with the one-way lock mechanism 9 and the protrusion start load regulating means 10, and the one-way lock mechanism 35 and the fuse (C-shaped portion) are provided. Needless to say, 34a and pin 38) may be omitted. Since the configuration of the other parts of the power generator 8 is the same as that of the first embodiment, the description thereof will be omitted. As shown in FIG. 10, the working end opening 13c and the stepped portion 13b of the cylinder 13 may be reduced in diameter by swaging (drawing) so that the outer peripheral surface of the intermediate portion of the piston rod 11b is in sliding contact with each other.

When assembling the power generator 8 to the pretensioner device P, the cylinder 13 is fixed to the base plate 31, the piston rod 11b is inserted from the operating end opening 13c of the cylinder 13, and the free end portion thereof is inserted into the link member 34. Connect with pin 39.

[0038] The operation procedure of this embodiment will be described below. First, when a vehicle collision is detected by a deceleration sensor (not shown), the thrust of the gas generator 14 is ignited, and the thrust of the piston member 11 pushed out by the combustion gas pressure generated at this time pushes the link member 34. It is transmitted to the arm 32 via and converted into the thrust of the arm 32. Then, the buckle 28 is pulled in as the arm 32 rotates (see FIG. 11), and tension is applied to the seat belt 23 to increase the restraining force of the occupant. At this time, even if the combustion gas pressure disappears, the one-way lock mechanism 35 prevents the arm 32 from reversing, so that the seat belt 23 is prevented from loosening after the combustion gas pressure disappears.

[0039] FIG. 12 is a diagram similar to FIG. 10 showing a modified example of the power generator having the above configuration, in which the outer diameter of the cylinder 13 is made substantially constant over the entire length thereof, and the wall thickness of the inner hole 13a thereof is changed. As a result, the step portion 13b is formed. This facilitates the assembly of the power generator 8. Other than that, the structure is the same as in FIG.

[0040] FIG. 13 is a diagram similar to FIG. 9 showing a modified example of the above configuration. A flange 13d is formed in the vicinity of the operating end opening 13c of the cylinder 13, and the reaction force when gas is generated is applied to the rear end of the cylinder 13. Not only the flange 13d but also the flange 13d can receive the force so that the force can be dispersed. Other than that, the structure is the same as in FIG.

FIG. 14 is a diagram similar to FIG. 2 showing a third embodiment to which the present invention has been applied. In this configuration, in addition to the configuration of the occupant restraint device shown in FIGS. 2 to 6, a pretensioner device 41 for automatically increasing the tension force of the seat belt in the event of a vehicle collision or the like is provided. Since the configuration of the sub-assembly 4 (the structure of the power generator 8, the one-way lock mechanism 9, the protrusion start load defining means 10, etc.) is the same as that of the first embodiment, the illustration and description thereof will be omitted. In this configuration, the power generator 8 of the sub-assembly 4 in the configuration of the occupant restraint device of FIG. 2 moves the buckle 42 of the seat belt to the side where the seat belt is tense in the pretensioner device 41. Also serves as a power generator. Further, the one-way lock mechanism 9 also serves as a lock mechanism for holding the buckle 42 of the seatbelt in the pretensioner device 41 in a state of being moved to the side where the seatbelt is tense. Further, in order to prevent the buckle 42 of the seat belt from inadvertently moving during normal use, the slip-out prevention member protrusion start load defining means 10 also serves as a means for defining the movement start load of the buckle 42. As a result, the power generator of both devices, the locking mechanism, and the means for defining the starting load of operation can be shared, and the number of parts can be reduced.

[0042] Specifically, the base end portion of the buckle 42 is connected to the free end portion of the piston member 11 of the power generator 8 via the link member 43 and the rotating arm 44. As a result, when an impact such as a collision is detected by a sensor or the like (not shown) during traveling, gas is generated by the gas generator 14, and the internal pressure of the cylinder 13 is rapidly increased to the free end side of the piston member 11. Is instantly projected from the cylinder 13, and the buckle 42 is pulled downward (imaginary line) at the same time as the slip-out prevention member 7 moves upward (projects) (imaginary line) as described above, and tension is applied to the seat belt. To increase the binding force of the occupants.

[0043] In each of the above configurations, the power generator according to the present invention is applied to the occupant restraint device and the seatbelt pretensioner device for preventing the submarine phenomenon, but the present invention is not limited to this, and the driver hits the steering wheel in the event of a collision. Needless to say, it can be easily applied to applications that generate instantaneous driving force, such as a device that moves the steering wheel forward to prevent collision.

[Effect of the Invention] As described above, according to the present invention, in order to prevent the occupant from slipping forward from the lower part of the seat belt when an impact such as a vehicle collision occurs, the casing fixed to the seat frame when the impact occurs. In the occupant restraint device that projects upward with a power generator and holds it with a lock mechanism at a position where the anti-slip member that is movably supported so as to project upward is received in the cylinder and one end of the anti-slip member is received. A power generator having a structure in which the piston member directly or indirectly engaged with the piston member is projected by a gas generating means for rapidly increasing the internal pressure of the cylinder, and the piston member is urged by a spring in the projecting direction. Therefore, the occupant restraint device does not become large and its backlash is eliminated.

[0045] A piston member that directly or indirectly engages with the driven member is received in a cylinder fixed to drive the driven member instantaneously, and the cylinder is subjected to gas generating means that is also received in the cylinder. In a cylinder in a power generator that rapidly increases the internal pressure to move the piston member in the protruding direction, the piston member is supported by a step portion provided on the cylinder and the piston member is urged in the protruding direction. By providing a spring arranged between the gas generating means and the tip of the gas generating means entering the central through hole of the spring, the extra space can be effectively used and the power generator can be miniaturized. At the same time, the initial volume at the time of gas generation can be reduced, that is, the amount of propellant used for the gas generation means can be reduced.

[0046] Further, the tip of the gas generating means rushes into the central through hole of the spring means to such an extent that a gap is secured between the piston member and the tip of the gas generating means from which the gas of the gas generating means is ejected even when the spring means is fully contracted. By doing so, the gas generating means and the spring means partially overlap to shorten the total length of the cylinder, or to lengthen the piston stroke with the same length, or to increase the gas generating means and without providing a separate spacer. Interference between the piston and the gas generating means can be prevented. Further, the gas generating means is composed of a large diameter portion on the base end side and a small diameter portion on the tip end side, and the step portion between them is a spring seat, so that the number of parts can be reduced and the step portion of the gas generating means has elasticity. By engaging the step portion formed on the cylinder via the seal member, it is possible to absorb the dimensional error and the assembly error between the cylinder and the gas generating means.

BRIEF DESCRIPTION OF THE DRAWINGS [FIG. 1] A partially exploded perspective view of a vehicle seat device according to a first embodiment to which the present invention is applied.

2 is a partially fractured side view of the vehicle seat device of FIG. 1. FIG.

FIG. 3 is an exploded perspective view showing a configuration of a sub-assembly of a occupant restraint device to which the present invention is applied.

FIG. 4 is a cross-sectional view showing the structure of a power generator of the occupant restraint device to which the present invention is applied.

FIG. 5 is a cross-sectional view showing another structure of the power generator of the occupant restraint device to which the present invention is applied.

6 is a perspective view of a main part of FIG. 4. FIG.

FIG. 7 is a perspective view of a seatbelt pretensioner device and a seat circumference including a power generator according to a second embodiment to which the present invention is applied.

FIG. 8 is a side view of a seatbelt pretensioner device to which the present invention has been applied.

FIG. 9 is a bottom view of a seatbelt pretensioner device to which the present invention has been applied.

FIG. 10 is a cross-sectional view showing the structure of the power generator according to the present invention.

FIG. 11 is a diagram illustrating an operation procedure of a seatbelt pretensioner device to which the present invention is applied.

FIG. 12 is a diagram similar to FIG. 10 showing a modified example of the power generator according to the present invention.

FIG. 13 is a diagram similar to FIG. 10 showing a modified example of the power generator according to the present invention.

FIG. 14 is a side view similar to FIG. 2 showing a configuration of a occupant restraint device according to a third embodiment to which the present invention is applied.

FIG. 15 is a diagram similar to FIG. 4 or FIG. 10 showing the structure of a power generator of a conventional seatbelt pretensioner device.

[Explanation of symbols] 1 Vehicle seat 2 Seat rail 3 Seat frame 4 Sub-assembly of occupant restraint device 5 Casing 5a Main body 5b Lid 5c Guide hole 5d Support 5e Fastening part 6 Arm 6a Color 6b Long hole 7 Anti-slip member 8 Power generator 9 One-way lock mechanism 10 Anti-slip member protruding start load defining means 10a Engagement part 10b Opening 10c Thin wall part 10d Central opening 11 Piston member 11a Piston body 11b Piston rod 11c Thread groove 12 Pin 13 Cylinder 13a Inner hole 13b Step Part 13c Working end opening 13d Thin wall part 14 Gas generator 14a Base end measuring large diameter part 14b Tip side small diameter part 14c Step part 15 Sealing member 16 Compression coil spring 17 O-ring 18 Casing 18a Large diameter part 18b Tapered part 18c Engagement groove 19 Engagement piece 20 Spring 21 Center pillar 22 ELR device 23 Seat belt 24 Through ring 25 Seat 26 End 27 Tongue plate 28 Buckle 28a Anchor P pretensioner device 31 Base plate 32 Arm 33 Actuator 34 Link member 34a C-shaped part 35 Check valve 36 Center shaft 37 Anchor pin 38, 39 Pin 41 Pretensioner device 42 Buckle 43 Link member 44 Rotating arm 50 Power generator 51 Cylinder 51a Inner hole 51b Shrinkage Diameter 52 Piston 52a Free end 52b Base end 53 O-ring 54 Cap 54a Opening 55 Gas generator 57 Holding plate