JP2000326825A - Occupant restraint device and power generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance high operation reliability, to facilitate assembling and to miniaturize a device by using a power generating device of a structure projecting a piston member by a gas generation means for suddenly increasing internal pressure of a cylinder and energizing the piston member in the projecting direction by a spring. SOLUTION: A power generating device 8 has a cylinder 13 fixed to a sheet frame via a casing, a piston main body 11a received so that it may appear or disappear within an inner hole 13a of the cylinder 13 and a gas generating device 14 as a gas generation means received to a base end side, than the piston main body 11a. Between the piston main body 11a and the gas generating device 14, a seal member 15 having elasticity and a compressive oil spring 16 are interposed and always energize towards the piston main body 11a operating direction (projecting direction). The seal member 15 is allowable if it has elasticity in an axis direction and is capable of surely preventing the leakage when gas is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant restraint device incorporated in a vehicle seat device for preventing an occupant from slipping forward from a lower portion of a seatbelt in the event of an impact such as a vehicle collision. The present invention relates to a power generation device for instantaneously driving a driven member suitable for use in a high-speed operation mechanism.

[0002]

2. Description of the Related Art Conventionally, there has been a so-called submarine phenomenon in which an occupant slides forward from a lower portion of a seat belt when an impact such as a vehicle collision occurs, and a waist belt comes off a pelvis portion. This submarine phenomenon is likely to occur when the occupant sits in the seat shallow or leans down the seat back, and in some cases, the occupant restraint effect of the seat belt is reduced, and the occupant restraint part is shifted. there were.

For example, it is conceivable to prevent the submarine phenomenon by providing a projection at the front end of the seat frame or providing a panel to increase the front end, but if the projection or panel is too low, a sufficient effect cannot be obtained. However, when the height is high, there is a disadvantage that a feeling of a foreign substance is generated at the time of normal use and riding comfort is deteriorated.

In order to raise the front end of the sheet only when an impact occurs, an airbag is used (see, for example, JP-A-5-229378, JP-A-7-81466, and JP-A-3-227745). ) Or a device that mechanically lifts the front end of the sheet (Japanese Utility Model Laid-Open No. 2-1493).
No. 28, Japanese Utility Model Application Laid-Open No. 3-121947, Japanese Utility Model Application Laid-Open No. 4
(See Japanese Patent Application Laid-Open No. 3-62440), and a device that mechanically lifts the leading end of a sheet using a high-pressure gas generated by a chemical reaction as a power generation device (see Japanese Utility Model Application Laid-Open No. 3-61440).
There is.

A conventional power generator 50 using high-pressure gas
Is shown in FIG. An inner hole 51 having a reduced diameter portion 51b at an intermediate portion is provided in a cylinder 51 fixed to a base member of a seat.
a is formed, and a piston 52 is received at one end portion thereof. For example, the free end 52a of the piston 52, which is integrally held by the main body by being screwed together, protrudes from one end opening of the cylinder 51 and engages with the front end of the seat via a link member or the like. The diameter is slightly increased, and is in contact with the inner peripheral surface of the cylinder 51 via an O-ring 53. A cap 54 having an opening 54a at the center thereof is fastened to one end opening of the cylinder 51. The opening 54a functions as a bearing when the piston 52 moves by slidingly contacting an intermediate portion of the piston 52.

A gas generator 55 is received in the other end of the inner hole 51a of the cylinder 51. The rear end opening of the cylinder 51 is caulked via a holding plate 57 also serving as a seal, and keeps the gas generator 55 from coming off.

[0007]

In the above structure, the piston 52 is assembled in a state where it is most immersed in the inner hole 51a of the cylinder 51. However, the gap between the base end 52b of the piston 52 and the step of the reduced diameter portion 51b is increased. If the size is small, the dimensional error of the device component (for example, the connecting portion of the link member, the base member of the seat and the cylinder receiving portion), or the displacement of the link member at the time of assembling cannot be absorbed. There was a problem that became difficult. If, after assembly, the connection between the free end 52a of the piston 52 and the link member or the connection between the link member or the like and the front end of the seat has a backlash, the so-called thrust at the portion where the backlash occurs during operation. A phenomenon occurs, and the impact force causes local plastic deformation in each part, resulting in energy loss of high-pressure gas.

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 seat belt for restraining the occupant is fastened is rapidly attached to the seat of the automobile. There has been proposed a pretensioner device which is moved in a direction to increase the restraining force of the seat belt (US Pat. No. 4,70,704).
5,296).

In such a pretensioner device, a power generating device utilizing high-pressure gas generated by a chemical reaction to pull a buckle is used, as described in, for example, JP-A-10-181529. However, there is a problem that the backlash occurs as in the above case.

Therefore, it is preferable to incorporate a structure for absorbing this backlash into each device, but there is a problem that the size of the device is increased depending on the structure.

The present invention has been devised in order to solve such problems imposed on the prior art, and has an object to achieve high operation reliability, easy assembling, and further miniaturization. It is an object of the present invention to provide an occupant restraint device and a power generation device suitable for use in these high-speed operation mechanisms.

[0012]

According to the present invention, in order to achieve the above object, in order to prevent an occupant from slipping forward from a lower portion of a seat belt when an impact such as a vehicle collision occurs, the occupant is fixed to a seat frame when an impact occurs. In the occupant restraint device in which the anti-slip member movably supported so as to be able to protrude upward in the casing that has been protruded upward with the power generation device and held at that position with the lock mechanism, it is received in the cylinder and one end is A power generating device having a structure in which a piston member directly or indirectly engaged with a slip-out preventing member is protruded by gas generating means for rapidly increasing the internal pressure of a cylinder, and a structure in which the piston member is biased by a spring in a protruding direction. And

Further, a piston member directly or indirectly engaged with the driven member is received in a cylinder fixed to drive the driven member instantaneously, and the gas generating means is also received in the cylinder. The piston is supported by a step provided in the cylinder, and biases the piston member in the protruding direction in the cylinder in the power generating device for moving the piston member in the protruding direction by rapidly increasing the internal pressure of the cylinder. A spring is provided between the member and the gas generating means, and a tip of the gas generating means is inserted into a central through hole of the spring.

[0014]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

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

FIG. 3 shows the structure of the subassembly 4 of the occupant restraint device. Since the left and right subassemblies 4 have the same structure, only one on the right side as viewed from the front of the vehicle will be described, and illustration and detailed description of the other will be omitted.
The sub-assembly 4 of the occupant restraint device includes a rectangular cylindrical casing 5 and a collar 6 formed on the casing 5 by a support portion 5d.
a arm 6 rotatably supported in the vertical direction by a.
A bar-shaped slip-out preventing member 7 having both ends engaged with both arms 6, a power generating device 8 received by the casing 5 to drive the slip-out preventing member 7 via the arm 6, A one-way lock mechanism 9 supported by the casing 5 near the working end of the device 8 and a slip-out preventing member projection start load defining means 10 (FIGS. 4 and 6) attached to the one-way lock mechanism 9 are provided. I have. By engaging a pin 12 attached to a free end of a piston rod 11b of a piston member 11 of the power generation device 8, which will be described later, with a slot 6b provided at a position offset from the support portion 5d of the arm 6, the piston The free end of the rod 11b is connected to a position offset from the support 5d of the arm 6. Further, the pin 12 is inserted into the guide hole 5 c and the piston rod 11 formed in the casing 5.
b is guided in the direction of emergence. The power generating device 8
And the one-way lock mechanism 9
After being received in the main body 5a, the cover 5b is fixed and held in the casing 5 by caulking. In addition, color 6
The pin a and the pin 12 are prevented from coming off by caulking and expanding the tips.

As shown in FIG. 4, the power generation device 8 includes a cylinder 13 fixed to the seat frame 3 via the casing 5 and a piston body 11a reciprocally received in an inner hole 13a of the cylinder 13. And the piston body 11
and a gas generating device 14 as gas generating means received on the base end side with respect to a. A sealing member 15 having elasticity is provided between the piston body 11a and the gas generator 14.
And the compression coil spring 16 intervene, and the piston body 11a
Is always urged in the operation direction (projection direction). The seal member 15 may have any elasticity in the axial direction and can surely prevent leakage when gas is generated.

Here, the gas generator 14 has a large-diameter portion 14a at the base end and a small-diameter portion 14b at the distal end from which gas is ejected, and a step portion 14c between them has an annular sealing member 15 having elasticity. And abuts and engages with a step 13 b formed in the cylinder 13, and penetrates into the central through hole of the compression coil spring 16 through the central through hole of the seal member 15.
In addition, the step portion 14 c forms a spring seat of the compression coil spring 16 via the seal member 15. The gas generator 14
Of the distal end side small diameter portion 14b enters the central through hole of the compression coil spring 16 to such an extent that a gap is secured between the piston main body 11a and the distal end of the distal end side small diameter portion 14b of the gas generator 14 even during its most contraction. I have. Accordingly, even when an external force is generated to move the piston main body 11a toward the gas generator 14 during or after assembly, there is no fear that the piston main body 11a hits the front end of the small diameter portion 14b on the front end side of the gas generator 14, Damage and deformation of the gas generator 14 can be prevented. Further, the tip side small diameter portion 14b of the gas generator 14 also fills the inner hole of the step portion 13b of the cylinder 13 and further projects into the compression coil spring 16 so that the dead space can be filled. The initial volume can be reduced, that is, the propellant used for the gas generator 14 can be reduced.

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 is connected to the arm 6 abuts against the piston body 11a from the axial direction, and the piston body 11a and the piston rod 11b make the piston member 1a.
1 is configured. Here, the piston main body 11a and the piston rod 11b are formed by a curved surface having a curvature toward the center of the axis, such as a spherical concave portion, and a curved surface having a slightly smaller curvature, such as a spherical convex portion. The engagement (abutment) is achieved by the contact at the center portion, whereby the two are self-aligned, and the piston rod 11b is prevented from being twisted in the cylinder 13, which may cause energy loss or gas leakage due to eccentricity. There is no.

In actuality, as shown in FIG. 5, the piston body 11a and the piston rod 11b are tapered concave portions whose diameter gradually decreases toward the center of the axis, and the diameter of the taper is reduced more gradually than this taper. The engagement may be made by contact at the center portion with the tapered projection. The concave portion may have a tapered shape, and the convex portion may have a curved surface.

As described above, the compression coil spring 1
6 always urges the piston main body 11a in the operation direction, so that the piston rod 11b is also urged in the operation direction, and the backlash of the connection portion between the piston rod 11b and the arm 6 is absorbed. I have. The spring is not limited to a compression coil spring, but may be a disc spring or a rubber elastic body. The working end opening 13c of the cylinder 13 is reduced in diameter so that the outer peripheral surface of the intermediate portion of the piston rod 11b comes into sliding contact.

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 working end opening 13c of the cylinder 13, that is, from the base end side opening. Then, the gas generating device 14 is inserted and the base end side opening portion of the cylinder 13 is caulked via the holding plate. Since the assembly direction can be unified in this manner, the caulking is performed by using the proximal end opening 1 of the cylinder 13.
The ease of assembling is improved because there are enough points. At this time, since the elastic sealing member 15 is interposed between the step 13b of the cylinder 13 and the step 14c of the gas generator 14, the dimension A of the gas generator 14 and the cylinder 1
Even if the caulking dimension B or the like 3 varies, it can be absorbed by the elastic deformation of the seal member 15, so that there is no problem such as damaging or deforming the gas generator 14 even when caulking and assembling.

At this time, if the piston rod 11b is not assembled to the power generating device 8 but is handled as a separate part, even if the gas generating device 14 is activated for some reason, the piston body 11a Since it only moves, its handling is easy.
Also, since the piston body 11a is light, the cylinder 13
It is not necessary to provide a strong cap in the working end opening 13c, and it is only necessary to reduce the diameter of the opening. Therefore, the working end opening 13c 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, thereby improving the freedom of arrangement of the device and the ease of assembly. Further, since no cutting process for providing the cap is required, the ease of manufacturing the cylinder is improved.

A one-way lock mechanism 9 is provided at the tip of the power generation device 8. The one-way lock mechanism 9 includes a plurality of engagement pieces 19 surrounding the outer circumference of the piston rod 11b inside a casing 18 fixed to the casing 5 so as to cover the outer circumference of the piston member 11, and the engagement pieces 19. It has a structure that receives a 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 engagement piece 19 is gradually reduced in diameter from the free end side of the piston member 11 to the base end side. Further, the inside of the casing 18 includes a tapered portion 18b which gradually narrows from the large diameter portion 18a. Therefore, in the state of FIG.
9 is urged by the spring 20 and is pressed by the tapered portion 18b and is in contact with the outer peripheral surface of the piston member 11. However, when the piston member 11 moves in the protruding direction, it resists the urging force of the spring 20. Then, each engagement piece 19 also moves in the direction in which the piston member 11 protrudes, and reaches the large-diameter portion 18a.
To move away from 1, the piston member 11 is free to move. Conversely, when the piston member 11 is to be moved in the direction of immersion, each of the engaging pieces 19 is
8b so as to contact the outer peripheral surface of the piston member 11 to fix them. Here, an annular groove or a thread groove 11c is formed on the outer peripheral surface of the piston rod 11b. The groove 1 is also provided on the inner peripheral surface of each engagement piece 19.
An annular groove or screw groove 11c corresponding to 1c is formed. Therefore, when trying to move the piston member 11 in the direction of immersion, the inner peripheral surface of each engagement piece 19 and the outer peripheral surface of the piston member 11 engage so that both are firmly fixed at that position. Has become.

At the end of the one-way lock mechanism 9, a lid 18 for the casing 18 is provided with a sliding start preventing member projecting start load regulating means 10. The slip-out preventing member projection start load defining means 10 is fitted to the front end of the casing 18 and is fixed by engaging the engaging groove 18c with the engaging portion 10a of the slip-out preventing member projection start load defining means 10. ing. A groove 1 of the piston rod 11b
An opening 10b is formed in which an annular groove or a thread groove with which 1c is engaged is formed. A thin portion 10c is formed around the opening 10b. As a result, even if the piston member 11 normally moves in the protruding direction at normal times, the inner peripheral surface of the opening 10b and the annular groove or the thread groove 11c on the outer peripheral surface of the piston member 11 are engaged. It is designed to hold. However, when a load larger than the predetermined load, that is, a thrust by the gas generator 14 is applied, the thin portion 10c is broken, and the piston member 11 projects. Further, even when the sub-assembly 4 is transported before assembling, the piston member 11 does not fall off, and the handling thereof is improved.

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

An occupant restraint system is constituted by the sub-assemblies 4 of the left and right occupant restraint devices, impact generation detecting means including acceleration sensors and the like (not shown) and control means.

The occupant restraint system can be assembled to an existing seat at the time of assembling the seat. However, if the occupant restraint system is assembled simultaneously at the time of assembling the seat for welding or the like, the welding process is completed. Later, a power generator 8 with built-in gunpowder
The sub-assembly 4 of the occupant restraint device having Further, in this configuration, the seat frame 3 is mounted on the seat rail 2 via a slidable holder. However, a seat that can be tilted or lifted is mounted on the mounting bracket.

Next, the operation of the present embodiment will be described. First, during normal running, as described above, the opening 10
thread groove 11c on the inner peripheral surface of b and the outer peripheral surface of piston member 11
Are engaged with each other, the piston member 11, the arm 6 and the slip-out preventing member 7 engaged with the piston member 11 are kept at the position without being inadvertently moved. Then, when the occurrence of an impact such as a collision is detected by a sensor or the like (not shown), gas is generated by the gas generator 14 and the cylinder 1
3, the thrust in the protruding direction of the piston member 11 is generated, and the load is applied to the free end of the piston member 11, that is, the free end of the piston rod 11b. The engaging portion is input to the opening 10c of the slip-out preventing member projection start load defining means 10, breaks the thin portion 10d, and the free end side of the piston member 11 projects from the cylinder 13 instantaneously. 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 preventing member 7 moves upward (projects), and in some cases, the seat cushion is removed. It swells out and prevents the occupant's submarine phenomenon. Even if the gas generation by the gas generator 14 is completed and the driving force of the power generator 8 is lost, the one-way lock mechanism 9
Accordingly, the effect of preventing the submarine phenomenon is maintained without the upwardly moving slip-out preventing member 7 returning downward.

In this configuration, the same one-way lock mechanism is provided on both the left and right sides, and both sides are supported against the load from the occupant. However, only one can be used as long as the strength can be ensured. Different types may be used. For example, one side may be provided with the one-way lock device, and the other side may be provided with a ball one-way lock device which can be locked at a stepless position. Similarly, if the power generation devices are provided on both the left and right sides, one power generation device can be downsized, and the devices are dispersed on both sides of the seat, and there is an advantage that the size is not locally increased. If it is obtained, only one of them may be used.

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

The occupant seated on the seat 25 pulls out the seat belt 23 from the ELR device 22 and fastens the tongue plate 27 to the buckle 28 so that the seat belt 23 is stretched from the occupant's shoulder to the chest and around the waist. .

The pretensioner device P is for automatically increasing the tension of the seat belt 23 in the event of a vehicle collision or the like. As shown in FIGS. A base plate 31 for fixing, an arm 32 pivotally connected at one end to the base plate 31 and having the other end connected to an anchor portion 28a of the buckle 28, and a power generating device according to the present invention substantially fixed to the base plate 31 And a link member 34 having one end connected to the operating end of the power generation device 8 and the other end connected to a position at an appropriate radial distance from the pivot center of the arm 32 at the pivot end. And a one-way lock mechanism 35 including a well-known ball one-way lock mechanism for limiting the rotation direction of the arm 32 to only one direction.

A center shaft 36 for supporting the arm 32 is mounted on the base plate 31. One end of the arm 32 is rotatably stopped with respect to the center shaft 36, and an anchor pin 37 is fixed to the other end by projection welding or the like. Then, the anchor portion 28a of the buckle 28 is
The arm 32 is rotatably supported by a protruding portion from the side surface.

One end of the link member 34 is an operating end of the power generating device 8 similar to the first embodiment, that is, the piston rod 1
1b is connected to the free end portion so as to be relatively rotatable, and the other end is connected to the arm 32 so as to be relatively rotatable. The C-shaped portion 34a at the other end of the link member 34 is engaged with the pin 38 and forms a fuse for preventing the arm 32 from being rotated carelessly.

Here, in this embodiment, the one-way lock mechanism 35 and the fuse (C-shaped portion 34a, pin 38)
As shown in FIG. 10, the power generating device 8 is not provided with the one-way lock mechanism 9 and the (slip-out prevention member) projection start load regulating means 10 as shown in FIG.
Conversely, the power generating device 8 is provided with the one-way lock mechanism 9 and the protrusion start load regulating means 10 to provide the one-way lock mechanism 3.
It goes without saying that the fuse 5 and the fuse (C-shaped portion 34a, pin 38) may be omitted. The configuration of the other parts of the power generation device 8 is the same as that of the first embodiment, and the description thereof is omitted. As shown in FIG. 10, the working end opening 13c and the step 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 slides.

When assembling the power generating device 8 to the pretensioner device P, the cylinder 13 is
And the piston rod 11b is inserted through the working end opening 13c of the cylinder 13, and its free end is connected to the link member 34.
With a pin 39.

The operation of this embodiment will be described below. First, when a vehicle collision is detected by a deceleration sensor (not shown), the propellant 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 causes the link member 34 to move. Through arm 32
And is converted to the rotational power of the arm 32. Then, the buckle 28 is retracted with the rotation of the arm 32 (see FIG. 11), and tension is applied to the seat belt 23 to increase the restraining force of the occupant. At this time, the one-way lock mechanism 35 prevents the arm 32 from reversing even if the combustion gas pressure disappears.
Is prevented from loosening.

FIG. 12 is a view similar to FIG. 10 showing a modified example of the power generating apparatus having the above-mentioned structure. The outer diameter of the cylinder 13 is made substantially constant over its entire length, and the thickness of the inner hole 13a is changed. This forms the step 13b. This facilitates the assembly of the power generation device 8. Other structures are the same as those in FIG.

FIG. 13 is a view similar to FIG. 9 showing a modification of the above configuration, in which a flange 13d is formed near the working end opening 13c of the cylinder 13, and the reaction force at the time of gas generation is reduced by the rear end of the cylinder 13. In addition to receiving the force not only on the flange 13d but also on the flange 13d, the force can be dispersed. Other structures are the same as those in FIG.

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

Specifically, the base end of the buckle 42 is connected to the free end of the piston member 11 of the power generator 8 via a link member 43 and a rotating arm 44. Accordingly, 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, so that the free end side of the piston member 11 Is instantaneously protruded from the cylinder 13, and as described above, the anti-slip member 7 moves upward (projects) (imaginary line), and at the same time, the buckle 42 is retracted downward (imaginary line), and tension is applied to the seat belt. To increase occupant restraint.

In each of the above configurations, the power generating device according to the present invention is applied to an occupant restraint device or a seat belt pretensioner device for preventing a submarine phenomenon. However, the present invention is not limited to this. It is needless to say that the present invention can be easily applied to an application for generating an instantaneous driving force, such as a device for moving the handle forward to prevent the collision.

[0044]

As described above, according to the present invention, in order to prevent the occupant from slipping forward from the lower portion of the seat belt when an impact such as a vehicle collision occurs, the occupant is moved upward by the casing fixed to the seat frame when the impact occurs. In an occupant restraint device in which a protruding and movably supported slip-out preventing member is protruded upward by a power generating device and held at that position by a lock mechanism, one end is received directly in the cylinder and one end of the slip-out preventing member is directly or By using a power generating device having a structure in which the indirectly engaged piston member is protruded by gas generating means for rapidly increasing the internal pressure of the cylinder, and having a structure in which the piston member is biased by a spring in the protruding direction, the occupant The rattling is eliminated without increasing the size of the restraining device.

A piston member directly or indirectly engaged 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 causes the cylinder to be driven. In a power generating device for moving the piston member in the protruding direction by rapidly increasing the internal pressure, the piston member is supported by a step provided in the cylinder, and biases the piston member in the protruding direction. By providing a spring disposed between the gas generating means and the tip of the gas generating means being inserted into the center through hole of the spring, extra space can be effectively used,
The power generator can be reduced in size and the initial volume at the time of gas generation can be reduced, that is, the propellant used for the gas generating means can be reduced.

The distal end of the gas generating means projects into the central through hole of the spring means so that a gap is secured between the piston member and the distal end of the gas generating means from which the gas is ejected even when the spring means is most contracted. By doing so, the gas generating means and the spring means partially overlap to shorten the overall length of the cylinder, or increase the piston stroke for the same length, or increase the gas generating means and without providing a separate spacer. Interference between the piston and the gas generating means can be prevented. Also,
The gas generating means is composed of a proximal-side large-diameter portion and a distal-side small-diameter portion, and the step between them is a spring seat, so that the number of parts can be reduced and the gas generating means has an elastic sealing member at the step. By engaging the step formed on the cylinder via the through hole, a dimensional error and an assembly error between the cylinder and the gas generating means can be absorbed.

[Brief description of the drawings]

FIG. 1 is a partially exploded perspective view of a vehicle seat device according to a first embodiment to which the present invention is applied.

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

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

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

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

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

FIG. 7 is a perspective view of a pretensioner device of a seat belt including a power generation device according to a second embodiment to which the present invention is applied and around a seat;

FIG. 8 is a side view of a seat belt pretensioner device to which the present invention is applied.

FIG. 9 is a bottom view of the seat belt pretensioner device to which the present invention is applied.

FIG. 10 is a sectional view showing the structure of a power generating device according to the present invention.

FIG. 11 is a diagram illustrating the operation of a seat belt pretensioner device to which the present invention is applied.

FIG. 12 is a view similar to FIG. 10 showing a modified example of the power generation device according to the present invention.

FIG. 13 is a view similar to FIG. 10 showing a modified example of the power generation device according to the present invention.

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

FIG. 15 is a view similar to FIG. 4 or FIG. 10 showing a structure of a power generation device of a conventional seat belt pretensioner device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle seat 2 Seat rail 3 Seat frame 4 Subassembly of occupant restraint device 5 Casing 5a Body 5b Cover 5c Guide hole 5d Supporting portion 5e Fastening portion 6 Arm 6a Collar 6b Long hole 7 Slip-out prevention member 8 Power generation device 9 One-way lock mechanism 10 Slip-out prevention member projecting start load defining means 10a Engagement part 10b Opening 10c Thin part 10d Central opening 11 Piston member 11a Piston body 11b Piston rod 11c Screw groove 12 Pin 13 Cylinder 13a Inner hole 13b Step 13c Working end opening 13d Thin portion 14 Gas generator 14a Base end large-diameter portion 14b Tip-side small-diameter portion 14c Step 15 Seal member 16 Compression coil spring 17 O-ring 18 Casing 18a Large-diameter portion 18b Taper portion 18c Engagement groove 19 Engagement piece 0 spring 21 center pillar 22 ELR device 23 seat belt 24 through ring 25 seat 26 end 27 tongue plate 28 buckle 28a anchor portion P pretensioner device 31 base plate 32 arm 33 actuator 34 link member 34a C-shaped portion 35 check device 36 Center shaft 37 Anchor pins 38, 39 pins 41 Pretensioner device 42 Buckle 43 Link member 44 Rotating arm 50 Power generation device 51 Cylinder 51a Inner hole 51b Reduced diameter portion 52 Piston 52a Free end 52b Base end 53 O-ring 54 Cap 54a Opening 55 Gas generator 57 Pressing plate

Claims (8)

[Claims] 1. A slip-out preventing member movably supported by a casing fixed to a seat frame so as to protrude upward so as to prevent an occupant from slipping forward from a lower portion of a seat belt when an impact such as a vehicle collision occurs. An occupant restraint system comprising: a lock mechanism for holding the slide-out preventing member projecting upward at a projecting position; and a power generation device for driving the slide-out prevention member, wherein the power generation device includes a cylinder. A piston member that is received in the cylinder and projects from one end opening thereof and directly or indirectly engages with the slip-out preventing member; and a gas received in the cylinder to rapidly increase the internal pressure of the cylinder. Occupant restraint, comprising: generating means; and a spring for urging the piston member in a protruding direction within the cylinder. Apparatus. 2. A power generator for driving a driven member instantaneously, comprising: a cylinder; a cylinder; A piston member to be engaged, gas generating means received in the cylinder to rapidly increase the internal pressure of the cylinder, and the piston member and the gas to urge the piston member in a protruding direction within the cylinder. And a spring disposed between the spring and the generating means, wherein a tip end of the gas generating means enters a central through hole of the spring. 3. The center passage of the spring such that the distal end of the gas generating means secures a gap between the piston member and the distal end of the gas generating means from which gas is ejected even when the spring is most contracted. The power generator according to claim 2, wherein the power generator is inserted into the hole. 4. The gas generating means has a large-diameter portion on the proximal end and a small-diameter portion on the distal end from which gas is ejected, and a step between them forms a spring seat of the spring. Claim 2
Or the power generator according to claim 3. 5. The power generating apparatus according to claim 4, wherein a step formed on said cylinder is engaged with a step of said gas generating means via a sealing member having elasticity. 6. A free end, wherein said piston member is detachably engaged with said piston main body having a size not protruding from said cylinder even when power is generated, said base end being detachably engaged with said piston main body from said one end opening side of said cylinder. The power generator according to any one of claims 2 to 5, wherein the power generator comprises a piston rod directly or indirectly engaged with the driven member. 7. A contact between the piston body and the piston rod at a central portion between a concave portion having a curved surface toward the center of the axis and a convex portion having a slightly smaller curved surface than the concave portion. The power generation device according to claim 6, wherein the power generation device is engaged. 8. The piston body and the piston rod have a tapered concave portion gradually reduced in diameter toward the center of the axis and a convex portion formed in a curved surface or a tapered shape in which the diameter is reduced more gradually than the taper. The power generation device according to claim 6, wherein the power generation device is engaged by contact at a central portion with the projection that forms the power generation device.