JP2890167B2 - Starter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat belt tightening device for rotating a winding shaft of a retractor in a seat belt retracting direction at the time of a vehicle collision, or an impact at the time of collision of an occupant by an air bag rapidly inflated with gas. The present invention relates to an activation device that operates an airbag device that protects from an airbag.

[0002]

2. Description of the Related Art In recent years, passive restraint devices such as seat belt tightening devices and airbag devices have been widely used for the purpose of protecting occupants in an emergency such as a vehicle collision.
This seat belt tightening device connects a piston to one end of a cord body wound around a pulley that is attached to a winding shaft (shaft) of a retractor, and connects the piston to a piston slidably received in the cylinder. The thrust by the expansion pressure of the acting gas exerts a tension on the cord, and the cord pulls the retractor shaft in the webbing winding direction and drives the retractor to remove the webbing in a state of being wrapped around the occupant. It is for emergency use.

In this airbag device, for example, a module composed of a center pad, a folded airbag, an inflator (gas generator), and the like is housed in a steering wheel. By instantly inflating the airbag with the rapidly burned gas, the inflated airbag receives the occupant's body and suppresses the impact force applied to the human body.

As a starting device for detecting a vehicle collision and activating the seat belt tightening device and the airbag device, for example, an operation of an inertial body which is displaced by an inertial force at the time of a collision of a vehicle is usually used for non-operation. 2. Description of the Related Art There is a mechanical actuating device that injects a firing pin held in an operating position toward a primer, thereby igniting an igniter, and activating a seat belt tightening device and an airbag device by its explosive force.

FIG. 6 shows a conventional example used in a seat belt tightening device in this mechanical starting device. The firing pin operating device 120 shown here is a pretensioner device 1
A housing 121 is attached to an end of the housing 30. The housing 121 has a cap 125 having a function of guiding a firing pin 124 on the primer side, and a through hole 102d provided in the housing 121.

[0006] A cylindrical firing pin 124 is mounted on the housing 121 so as to be slidable in the axial direction. The tip of this firing pin 124 is formed into a sharp and sharp shape, and the tip is inserted through the through hole 102d, while the rear end is urged by a spring 140. In a normal state, the flange 141 attached in the middle of the firing pin 124 is locked by the trigger 142.

The pretensioner device 110 has a substantially L-shape including a cylindrical housing 111 containing a gas generator 130 and a cylinder 112 screwed to the end of the housing 111. This gas generator 130
Is a gas generating agent 132 sealed in a bottomed cylindrical case 131 (shown in a broken state in the figure);
The gas generating agent 132 is sealed and a primer 133
And a detonator holder 134 for holding the on-axis line.

When a sharp inertia force greater than a predetermined magnitude acts due to a collision of an automobile or the like,
The balancer 143 oscillatingly held by the shaft 144 oscillates, whereby the trigger 142 swings about the shaft 145 and operates so as to come off the flange 141. As a result, the firing pin 124 is displaced toward the gas generator 130,
The sharp tip pierces the primer 133 and ignites it. The gas generating agent 13 ignited by the firing of the primer 133
2 generates a large amount of hot gas G.

This high-temperature gas G is supplied to a case 13 as shown in FIG.
1 is pierced through the bottom of the pre-tensioner device 110 and jetted into the gas chamber 113 of the pre-tensioner device 110. Thereby, the piston 11 provided in the cylinder 112 of the pretensioner device 110 is
5 is driven by the gas pressure P to be displaced in the cylinder, and the wire cable 116 connected to the piston 115
Is pulled by a pulling force F. As a result, the take-up reel around which the wire cable 116 is wound is urged in the direction in which the seat belt is wound, so that slack of the belt is eliminated. Therefore, the occupant's body is strongly restrained by the seat by the seat belt having no slack, so that the displacement amount to the front of the vehicle body due to the impact of the collision is reduced, and it is possible to prevent an injury due to a collision with the steering wheel or the like. .

[0010]

However, the cap 125 closing one end of the gas generator 130 has a through hole 102d through which a firing pin 124 penetrates. Naturally, the diameter of the through hole 102d is equal to the firing pin. 124 is larger than the outer shape. As a result, a part of the high-temperature and high-pressure gas G generated by the chemical 132 flows backward to the opposite side of the cylinder and leaks into the housing 121. When the amount of the jet gas is large, there are problems that the gas pressure has to be increased and that setting of the gas pressure becomes difficult.

Therefore, as shown in FIG.
A V-packing 151 and an O-ring 152 are provided in a hole 150 having a hole 3 so that the O-ring and the like are bent by the reverse pressure of gas.
154371). However, when the V-packing 151 and the O-ring 152 are pressed in the axial direction of the firing pin 124 to bend, the bending does not occur uniformly. There was a problem that occurred.

Japanese Patent Application Laid-Open No. Hei 6-27132 discloses a substantially cylindrical coupler seal having a seal lip which can abut on the outer peripheral surface of a firing pin and extends along the outer peripheral surface. Is shown. However, since the seal lip itself receives gas pressure and has a shape extending along the outer peripheral surface of the firing pin, it is difficult to bend uniformly by gas pressure, and the strength of the reel lip is increased. In this case, a gap is easily formed. On the other hand, if the strength is weakened, a situation in which the seal is rolled up due to gas pressure occurs and the sealing function cannot be guaranteed.

This is not limited to the above-described seat belt retractor, but also in the case of an airbag provided inside the steering wheel or other places, as long as the mounting method of the gas generator and the like is similar. The same is true. The present invention has been made in view of the above circumstances, and has as its object to provide a starting device that can reliably prevent gas leaking from a gas generator along a firing pin.

[0014]

SUMMARY OF THE INVENTION It is an object of the present invention to detect the collision of a vehicle by utilizing the operation of an inertial body which is displaced by the inertial force at the time of the collision of the vehicle, and to adjust the winding shaft of the retractor to a seat belt. A starting device for operating a seat belt tightening device that rotates in a retracting direction or an air bag device that protects an occupant from an impact at the time of a collision by an air bag that is rapidly inflated with gas. A housing accommodating a firing pin that collide with the primer in conjunction therewith is provided with a through hole that allows the firing pin to collide with the primer, and a through hole on the side of the primer in the through hole extends along the outer periphery of the firing pin. A ring-shaped contact member is provided which is deformable inwardly of the firing pin radius so as to abut against the circumference, and surrounds the outer periphery of the firing pin at a position closer to the detonator than the close contact member, and has Movable in said deformable phosphorus
Ring-shaped member that is less deformable than the contact-shaped contact member in the shape of a bush is provided, and the contact-contact member is pressed by the annular member that receives pressure in the firing pin axial direction accompanying the expansion of the gas, This is achieved by an activation device characterized in that it is configured to bulge inwardly into the firing pin radius.

[0015]

According to the above construction of the present invention, when the firing pin penetrates through the through hole of the housing and collides with the primer in the event of an operation of the inertial body in an emergency, the gas pressure flowing backward is received by the annular member, This annular member uniformly presses the contact member against the wall surface substantially along the radial direction of the firing pin over its entire circumference. As a result, the close contact member is deformed inward in the radial direction of the firing pin, and its inner diameter is reduced uniformly, so that the inner peripheral surface of the close contact member reliably contacts the outer peripheral surface of the firing pin.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a partial front view of a retractor 1 with a pretensioner provided with a starting device according to a first embodiment of the present invention. The retractor 1 with a pretensioner is provided with a take-up reel (located between the emergency lock mechanism 13 and the pretensioner 3) on which the webbing 16 is wound up or pulled out freely. The webbing 16 is constantly urged in a direction in which the webbing 16 is wound by a winding spring connected to the winding shaft. In the event of a collision, the rotation of the winding shaft is prevented by a known emergency lock mechanism 13 so that the webbing 16 is not pulled out any further.

The retractor 1 with a pretensioner has a retractor base 1 formed in a substantially U-shape.
A pretensioner 3, which is a seat belt tightening device for rotating the take-up shaft in a direction in which the slack of the seat belt is removed at the time of a vehicle collision, is provided on one base side wall of the base member 8. Then, the retractor 1 with the pretensioner is attached to the vehicle body panel as an assembly (assembly) in which the pretensioner 3 is previously assembled integrally with the retractor.

The pretensioner 3 applies a tension to a wire 7 which is a transmission member wound around a pulley (not shown) attached to one end of a winding shaft, for example, and the wire 7 moves the winding shaft in a webbing winding direction. The webbing 1 is in a state of being stretched over the occupant by being driven to retract.
6 is drawn in an emergency, and includes a driving unit 4 for applying tension to the wire 7 and an activation device 21 for detecting a vehicle collision and operating the driving unit 4.

The driving means 4 includes a piston 6 connected to one end of a wire 7, a cylinder 5 for slidably receiving the piston 6, a base end of the cylinder 5, and a gas ejection portion of a gas generator 8. And a gas generator 8 that operates in response to an acceleration equal to or greater than a predetermined value. The cylinder side housing 15 is
It is a substantially L-shaped tube member bent at a substantially right angle, and the base end of the cylinder 5 is fixed to one opening 19 thereof.
The wire 7 connected to the piston 6 is inserted through a hole 20 provided opposite the opening 19.

The gas generator 8 incorporates a primer 10 in a case 12 which contains an explosive 11 and is sealed to a frame. When the primer 10 is hit and the explosive 11 is ignited, the inflation gas is ejected from the gas ejection portion at the tip of the case 12. Therefore, beside the primer 10 of the gas generator 8, the primer 10 is sandwiched by the side wall of the retractor base 18.
The starting device 21 for hitting is fixed.

As shown in FIG. 2, the starting device 21 is made of a non-magnetic material such as stainless steel and moves in the direction of the squib to collide with the squib 10 so as to ignite the squib 10. An inertial body 23 formed of a columnar permanent magnet having a through-hole 23a extending along the center axis, and an annular permanent magnet 24 having an inner diameter larger than the outer diameter of the inertial body 23; And a housing 25 fixed to the side wall of the retractor base 18 and a malfunction prevention mechanism 9 disposed in the housing 25 to prevent a malfunction of the activation device 21.

The firing pin 22 has a sharp tip 22a for striking the primer 10 at the tip and a flange 22b at the base, and the rear end is a housing 25.
Is slidably inserted into the bottom wall 25c of the housing 25.
It is installed inside. The firing pin 22 is relatively positioned with respect to the inertial body 23 when a caulking sleeve 22c attached to a rear end portion of the inertial body 23 that penetrates the through hole 23a contacts the bottom wall side end of the inertial body 23. In the initial state, movement to the primer side is restricted. Note that, instead of the crimping sleeve 22c, the position may be fixed by a screwing structure such as a nut so that the position can be adjusted.

The tip 22a of the firing pin penetrates a through hole 25b formed in a wall 25a on the primer side of the housing 25 and faces the primer 10 with a gap therebetween.
(FIG. 2 shows a state in which the firing pin is actuated, so that no gap is formed). Accordingly, when the inertial body 23 collides with the flange portion 22b (the inertial body moves to the primer side), the firing pin 22 moves to the primer side and the firing tip 22
a strikes and ignites the primer 10.

The annular permanent magnet 24 is fitted in the primer side of the housing 25, and the inertial body 23 penetrated by the firing pin 22 normally has the inertial body 23 on the bottom wall side of the housing 25 (anti-prime side). ).

In a state where the malfunction prevention mechanism 9 described later is released and the shaft 31 does not interfere with the inertial body 23 (the state shown in FIG. 2), the inertia of the inertial body multiplied by the weight of the inertial body 23 and the acceleration in the primer direction is used. When the force becomes larger than the repulsive force of the magnetic force, the inertial body 23 moves toward the primer as shown in FIG. That is, when the inertial body 23 moves to a region where the magnetic attraction acts on the inertial body 23, the inertia body 23 is accelerated in the primer direction by the magnetic attraction, and the annular permanent magnet 2
4 and collides with the flange 22b. As described above, the inertial body 23 has a function as an acceleration sensor by utilizing the fact that the magnetic force changes to repulsion and attraction, and a function as trigger means for starting the supply of impact energy to the firing pin 22.

The inertial body 23 accelerated in the direction of the primer by the attraction of the magnetic force moves the firing pin 22 in the direction of the primer, and strikes and ignites the primer 10 with the tip 22a of the firing pin. Is set so that the primer 10 is ignited until it contacts the inner wall surface of the through hole 25b. Further, the activation device 21 includes a malfunction prevention mechanism 9 for preventing the activation device 21 from malfunctioning before the retractor 1 with the pretensioner is assembled to the vehicle as an assembly.
It has.

The malfunction prevention mechanism 9 is provided, for example, between the annular permanent magnet 24 and the primer side end 23b of the inertial body 23 (before the inertial body moves) in a portion above the guide hole of the housing 25. The shaft 31 is inserted through a hole 25d provided so as to cross the inertial body 23. By rotation of the shaft 31, the inertial body 23 can be selectively brought into a movement preventing state and a movable state.

The shaft 31 has, for example, an enlarged diameter at one end to prevent it from falling out of the housing 25, a compression coil spring wound thereon, and a spring pin fixed to the other end by press-fitting. By operating, it can rotate within a predetermined range. An intermediate portion of the shaft 31 corresponding to the guide hole of the housing 25 is formed in a substantially semicircular cross section, and has a cutout portion 31a that can take a rotational phase that does not interfere with the inertial body 23.

The structure of the through-hole 25b for guiding the firing pin 22 to the primer 10 will be further described. As shown in FIG. 2, a ring receiving concave portion 26 having a substantially rectangular cross section is provided on the side of the primer 10 in the through hole 25b so as to increase the diameter of the through hole. A deformation ring 50 as a contact member is fitted. Also, moveable and the firing pin axis enclose the firing pin outer circumference position of the detonator nearer deformation ring 50, the deformable deformation
A plain washer 40, which is an annular member that is less likely to deform than the ring 50, is provided. The plain washer 40 has a flat shape so as to uniformly contact the side surface of the deformation ring 50. Further, the deforming ring 50 is provided with a contact surface 52 in which the center of the inner inner peripheral surface protrudes inward, and a groove 51 is formed on the outer periphery opposite to the contact surface 52.

The deformation ring 50 can be made of a relatively soft metal such as rubber, elastomer or aluminum. Therefore, as shown in FIG. 3, when the groove 51 is formed, the groove 51 functions as a pressure conversion unit for converting the gas pressure in the firing pin radial direction. That is, when the gas pressure in the axial direction of the firing pin 22 is generated, and when the gas is received from the lateral direction (the direction along the firing pin axis) by the action of the gas pressure and the side wall 26 a along the firing pin radial direction in the groove 51. At the same time, the groove 51 is relatively easily deformed so as to be crushed, and at this time, the contact surface 52 is deformed so as to reduce the inner diameter thereof, so that the contact surface 52 pushes the outer peripheral surface of the firing pin 22. Hit the outer peripheral surface. As a result, the through hole 25
Gas leaking outside through b can be suppressed.

Also, as in the present embodiment, the deformable ring 50
Is retractor base 1 with starter 21 attached
Gas leakage can be effectively prevented by being located on the primer side than 8.

Next, the operation of the retractor 1 with a pretensioner will be described. In the normal running state of the vehicle, the pretensioner 3 is not engaged with the winding shaft,
The winding shaft is freely rotatable. Therefore, the webbing 16 can be wound by the biasing force of the winding spring, and the webbing 16 can be pulled out against the spring force.

When a certain amount of deceleration such as sudden braking occurs in the vehicle, the emergency locking mechanism 1 of the retractor
3 operates to lock the rotation of the winding shaft. Thus, the extension of the webbing is prevented, but the inertial body 23
Is smaller than the repulsive force of the magnetic force acting between the annular permanent magnet 24 and the inertial body 23, and the activation device 21 does not operate, so that the driving means 4 of the pretensioner 3 does not operate.

On the other hand, when an extremely large predetermined deceleration occurs at the time of a vehicle collision or the like, the inertial force acting on the inertial body 23 is reduced by the magnetic force acting between the annular permanent magnet 24 and the inertial body 23. The inertia body 23 moves in the direction of the primer and collides with the flange portion 22b, so that the firing pin 2
2 strikes the primer 10 and ignites it. The ignition of the primer 10 causes the gas generator 8 in the drive means 4 to ignite,
When the gas generator 8 generates a combustion gas in the cylinder 5, the pressure of the generated gas causes the piston 6 to rapidly move upward (in the direction of the arrow X). When the wire 7 is rapidly pulled in the direction of the arrow X by a force of a predetermined magnitude by the driving force of the piston 6, the winding shaft is driven in the webbing winding direction, so that the winding shaft is wound around the occupant. Certain webbing 16 is retracted to remove seat belt play.

The present invention is not limited to the above embodiment,
The modification can be made as shown in FIGS. FIG.
In the configuration of the second embodiment shown in FIG. 5, the through hole 25b is provided with a ring receiving recess 26 having a substantially rectangular cross section so as to increase the diameter of the through hole, similarly to the first embodiment. An O-ring 60, which is a close contact member, is fitted into the ring receiving concave portion 26, and a position closer to the primer 10 than the O-ring 60 is smaller than the deformable O-ring 60.
A plain washer 61, which is an annular member that is difficult to deform, is provided. In short, the O-ring 60 is disposed so as to be sandwiched between the plain washer 61 and the side wall 26a of the ring receiving recess 26.

Accordingly, when a gas pressure in the axial direction of the firing pin 22 is generated, the plain washer 61 is pushed by the gas pressure (pushed to the counter-hitting pin side), and the plain washer 6 is pressed.
1, the O-ring 60 is pressed so as to be crushed from the lateral direction. At this time, the O-ring 60 is deformed so as to reduce its inner diameter, and the inner surface hits the outer peripheral surface of the firing pin 22 such that the inner surface presses the outer peripheral surface of the firing pin 22. As a result, gas leaking outside through the through-hole 25b can be suppressed.

The O-ring 60 can be made of a material other than a commercially available O-ring, such as an elastomer other than rubber, a relatively soft metal such as aluminum, or a rope-like fiber.

In each of the above embodiments, the starting device 21 is used.
Although a configuration using a magnet was used, it goes without saying that a configuration using an appropriate member other than the magnet may be used in the activation device of the present invention. In each of the above embodiments, the flange 22b of the firing pin 22 that is prevented from moving relative to the inertial body 23 in the primer direction is provided with the inertial body 23 that moves in the primer direction faster than the firing pin 22. Igniting the primer 10 by colliding with it, the speed of movement of the inertial body 23 is increased, and a sufficient speed for firing the primer 10 is obtained in a small space, but the firing pin is fixed to the inertial body. It is also possible to integrate them.

The members constituting the starting device of the present invention are not limited to the shapes in the above-described embodiments, but may take various forms based on the gist of the present invention. It goes without saying that each structure of the pretensioner can also be changed as appropriate. Further, in each of the above embodiments, the starting device of the present invention is applied as the starting device for operating the gas generator of the seat belt tightening device. However, the starting device for operating the gas generator of the airbag device is not limited thereto. It is equally applicable to devices.

[0040]

As described above, according to the starting device of the present invention, when the firing pin penetrates the through hole and collides with the primer in the event of an operation of the inertia body in an emergency, the close contact member is provided. the axial pressure of the firing pin associated with the expansion of the gas varying the
It is received through an annular member that is less deformable than the formable close contact member, and can be uniformly deformed over the entire circumference by being pressed with uniform pressure, and the inner part of the close contact member contacts the entire circumference of the firing pin outer peripheral surface. Therefore, the gas leaking to the outside through the through hole can be suppressed, the inflation pressure of the gas generating agent can be effectively used, and the peripheral parts can be prevented from being adversely affected by heat.

[Brief description of the drawings]

FIG. 1 is a partial front view of a retractor with a pretensioner provided with a starting device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the activation device shown in FIG.

FIG. 3 is an enlarged sectional view of a main part of the activation device shown in FIG. 1;

FIG. 4 is a longitudinal sectional view of a starting device according to a second embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a main part of the activation device shown in FIG. 4;

FIG. 6 is a schematic view of a partial cross section of a conventional activation device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 retractor with pretensioner 3 pretensioner 4 driving means 5 cylinder 13 emergency lock mechanism 16 webbing 21 activation device 22 firing pin 22a firing pin tip 22b flange 23 inertia body 24 annular permanent magnet 25 housing 25b through hole 26 ring receiving recess 40, 61 Plain washer (annular member) 50 Deformation ring (close contact member) 60 O-ring (close contact member)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60R 22/46 B60R 21/32

Claims (1)

(57) [Claims] 1. A seat belt tightening device for detecting a vehicle collision by utilizing an operation of an inertial body displaced by an inertial force at the time of a vehicle collision and rotating a winding shaft of a retractor in a seat belt retracting direction, or An activation device for activating an airbag device that protects an occupant from an impact at the time of a collision by an airbag that is rapidly inflated with gas, comprising: a firing pin that collides with a primer in conjunction with the operation of the inertial body. The accommodated housing is provided with a through hole that allows the firing pin to collide with the primer, and on the primer side of the through hole, inward of the firing pin radius so as to contact the entire circumference along the outer circumference of the firing pin. with headed deformable ring-shaped contact abutment member is provided, movable and the firing pin axis enclose the firing pin outer circumference position of the detonator nearer said seal adhesive contact member, the deformable phosphorus Jo of adhesion
An annular member that is less likely to deform than the abutting member is provided, and the contact abutting member is pressed by the annular member that has received pressure in the firing pin axial direction accompanying the expansion of the gas, so that the inner radius of the firing pin is reduced. An activation device, characterized in that the activation device is configured to bulge into the device.