JP2871363B2 - Hybrid ignition system for airbag device - Google Patents

Abstract

PURPOSE:To prevent the malfunction of a mechanical ignition device to be operated when an electrical ignition device is made nonoperational. CONSTITUTION:A mechanical ignition device 17 is provided on an inflator 13 electrically ignited at the time of a collision, and it is provided with a stopper pin 21 restricting the rolling of the steel ball 18 of the mechanical ignition device 17 rotated in the outside direction of a car body at the time of a collision to operate a firing hammer 20a striking a detonator 19. When a wire harness 16 connected to an electrical ignition device 13a is cut off, the rolling restriction by the stopper pin 21 is released, and the steel ball 18 is rolled to mechanically ignite the inflator 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inflator ignition system for inflating an airbag of an airbag device for protecting an occupant from a secondary collision at the time of a vehicle collision.

[0002]

2. Description of the Related Art For example, at the time of a side collision of a vehicle, a side airbag of an airbag device that inflates and deploys between a passenger compartment side wall and the like and an occupant to protect the occupant from a secondary collision is folded. It is generally housed in a case together with an inflator for inflating it, and housed in a side door facing a vehicle compartment, an armrest, or the like.

An acceleration sensor for detecting a collision of a vehicle is, for example, a monocoque sensor (see FIG. 5) of an airbag device described in the specification attached to the application for Japanese Patent Application No. Hei 4-10124. A floor tunnel 3 formed on the vehicle center line of the floor pan 2 of the body 1 and side sills 5 formed substantially parallel to the floor tunnel 3 on both sides of the floor pan 2 are connected to the vehicle center line. Cross members 6 and 6 provided at right angles to each other are provided. In addition, on the floor tunnel 3 provided on the center line of the vehicle body and at the position on the axis L of the cross members 6 and 6 connecting the both side faces of the floor tunnel 3 and both side sills 5 and 5, An acceleration sensor 7 is fixedly installed with a bolt or the like as a collision sensor. The acceleration sensor 7 detects an input of a load equal to or more than a predetermined value from the right side or the left side of the vehicle body, detects which side of the vehicle body has collided with a single collision sensor, and outputs a detection signal to an inflator ( (Not shown) to ignite the inflator, inflate the side airbag with the generated gas, and protect the occupant from a secondary collision with a vehicle interior side wall or the like.

[0004]

However, in the case where an inflator is ignited by transmitting a detection signal upon detection of a collision, as in the case of the acceleration sensor 7 of the airbag device described above, the acceleration sensor 7 and the ignition device for the inflator are used. (Not shown), directly or by computer (control device)
It is necessary to indirectly connect wiring via such as. Therefore, when the acceleration sensor 7 is disposed on a rigid body such as a body frame and the inflator and the airbag are disposed in a side door (not shown), the acceleration sensor and the power supply are connected to the inflator. The wire harness for connecting to the ignition device is disposed on the side of the vehicle body.
Therefore, in the event of a side collision of the vehicle, the wire harness may be cut when the side door or the like is deformed, and in order to prevent this, a structure in which a plurality of circuits are provided or the wire harness itself is strongly protected is provided. However, there is a problem that a burden such as cost, space, and weight is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an ignition system for an airbag device having means for mechanically igniting an ignition device of an inflator when a wiring such as a wire harness is cut. It is intended to provide.

[0006]

As a means for solving the above-mentioned problems, a hybrid ignition system for an airbag device according to the present invention is an airbag device provided with an electric ignition device for electrically igniting an inflator. The inflator includes a mechanical ignition device that mechanically ignites the inflator by utilizing inertia force at the time of a collision, and the mechanical ignition device is released from the operation regulation when the electric wiring to the electric ignition device is cut off during the collision. It is characterized in that it is provided with an operation restricting means.

[0007]

As described above, in addition to the electric ignition device, a mechanical ignition device for mechanically igniting the inflator using the inertia force at the time of collision is provided, and the mechanical ignition device is provided with an operation restricting means. When the electric wiring to the electric ignition device is cut, the regulation by the operation regulating means is released,
The mechanical ignition device becomes operable, and is activated by inertia force at the time of collision to mechanically ignite the inflator, and the gas generated inflates the airbag.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the hybrid ignition system of the present invention is applied to an ignition system of a side airbag device will be described below with reference to FIGS.

FIGS. 1 and 2 show a first embodiment of the present invention. An airbag 12 and an inflator 13 are provided in a side door 11 of a vehicle with a backup plate 14.
Although not shown, a wire harness 16 for passing an ignition signal and an ignition current at the time of collision detection is provided on a rigid body portion of the body, and is attached to the door inner panel 15. It is stretched between a control device (CPU) for determining a collision direction and the like and an inflator 13 provided on a side door.

A mechanical ignition device 17 is provided outside the inflator 13 outside the vehicle body (upper side in FIG. 1). As shown in a sectional plan view of FIG. 2, for example, the mechanical ignition device 17 divides the inside of the box-shaped case into two chambers in the front-rear direction of the vehicle body, and one of them accommodates a steel ball 18 in a rollable manner. At the same time, a detonator 19 for igniting the inflator 13 is provided on the other side so as to ignite a gas generating agent (not shown) in the inflator 13. An opening 17b is formed in the partition 17a of both chambers on the outer side of the vehicle body, and a lever 20 is inserted through the opening 17b so that the lever 20 can be rotated in a horizontal direction about a substantially center thereof. A hammer 20a is attached to the end of the lever 20 on the chamber side (right side in FIG. 2) where the primer 19 is provided. When the steel ball 18 rolls outward in the vehicle body due to inertial force at the time of collision and pushes one end of the lever 20 outward, the lever 20 rotates clockwise in FIG. A hammer 20a attached to the other end strikes the primer 19 to ignite the inflator 13.

Further, the mechanical ignition device 17 is provided with a stopper pin 21 as a safety device for preventing a malfunction due to an impact or the like at the time of assembling or opening / closing the side door. The steel ball 18 accommodated in one room is inserted into the apparatus from the front side of the vehicle body to regulate the rolling of the steel ball 18 toward the outside of the vehicle body (upward in FIG. 2). The end of the stopper pin 21 is connected to a wire 22 such as a piano wire, which has a high tensile strength and is hardly stretched, and is connected to a wire harness 16 provided in the side door 11. The front end extends from the side door 11 and is fixed to the body side.

In FIG. 1, reference numeral 23 denotes a trim cover which covers the interior of the airbag 12 housed in the side door 11 so as to be able to open and close.

Next, the operation of this embodiment constructed as described above will be described. When an electric acceleration sensor detects a side collision of a vehicle, the collision detection signal is transmitted to a control unit (CP).
U), the collision direction is determined, and a signal current flows from the control device to the inflator 13 of the side airbag device to be inflated in accordance with the determined collision direction. The gas flows into the squib (electric detonator) 13a, which is an ignition device, and the gas generating agent in the inflator 13 is ignited. Then, the airbag 12 is inflated by the gas generated from the inflator 13, and the inflated airbag 12 pushes open the trim cover 23 and deploys in the vehicle interior, thereby protecting the occupant from a secondary collision with a vehicle interior side wall or the like. . When the electric ignition method is operating normally as described above, the operation of the mechanical ignition device 17 is regulated by fixing the steel ball 18 with the stopper pin 21.

At the time of a side collision, when the wire harness 16 disposed on the side of the vehicle body is cut by being pulled by an outer plate or the like deformed by a collision vehicle, the wire harness 16 is stretched along the wire harness 16. Wire 22
Since the steel has high tensile strength and is hardly stretched, a large tensile force is applied without being cut. As a result, the stopper pin 21 connected to the end of the wire 22 is pulled out of the mechanical ignition device 17. Therefore, the mechanical ignition device 17
Operation of the steel ball 1 by the stopper pin 21
8 is released, the steel ball 18 rolls outward due to the inertial force at the time of collision, and pushes one end of the lever 20 outward (rolling direction). As a result, the hammer 20 a attached to the other end of the lever 20 that rotates about the center as a fulcrum strikes the primer 19 and ignites the inflator 13. Therefore, even if the wire harness 16 is cut off at the time of the collision and the electric ignition method does not operate, the inflator 13 is ignited by the mechanical ignition device 17 instead, and the airbag 12 is inflated by the generated gas to inflate the occupant. Can be protected.

FIGS. 3 and 4 show a second embodiment of the present invention. In a side door 31 of a vehicle, an airbag 32 and two inflators 33a and 33b are integrated with a backup plate 34. And a wire harness 36 for supplying an ignition current when a collision is detected is detected by a collision detection signal of an electric acceleration sensor (not shown) provided on a rigid body of the body. It is stretched between a control device (CPU) for determining the operation and the like and one inflator 33a provided on the side door. The inflator 33a includes a squib 33c as an electric ignition device.
A current flows through 3c to ignite the inflator 33a.

The other inflator 33b is provided with a mechanical ignition device 37 outside the vehicle body (upper side in FIG. 3). As shown in a sectional plan view of FIG. 4, for example, the mechanical ignition device 37 rotatably accommodates a steel ball 38 in the vehicle interior of the box-shaped case, and has a lever 40 on the outside of the vehicle body. The lever 40 is provided so as to be rotatable in a horizontal direction with a fulcrum as a fulcrum, and a primer 39 is provided on the inside of the lever 40 so as to ignite a gas generating agent (not shown) in the inflator 33b. . The mechanical ignition device 37 includes a solenoid type stopper 41 as a safety device for preventing a malfunction due to an impact when the side door is opened and closed.
Is provided on the front side of the mechanical ignition device 37, and this solenoid type stopper 41 is excited by energization, and the stopper pin 41a compresses the return spring 41b and protrudes into the case of the mechanical ignition device 37, The rolling of the steel balls 38 inside the steel balls 38 in the outward direction of the vehicle body is regulated. And, this solenoid type stopper 41
The other inflator 3 as a power source for exciting the
Wire harness 36 connected to squib 33c of 3a
The wiring 36a branched from a position very close to the inflator 33a is connected.

The solenoid type stopper 41 is
To prevent erroneous operation due to the impact of opening and closing the door when the ignition switch is turned off, it is linked to the ON / OFF of the courtesy lamp switch that lights when the door is opened, and a delay circuit by the capacitor (door closing operation) (Approximately 200 msec later) so that the solenoid-type stopper 41 is excited when the door is opened and closed, and the operation of the mechanical ignition device 37 is regulated.

In FIG. 3, reference numeral 42 denotes a trim cover which covers the interior of the airbag 32 housed in the side door 31 so as to be able to open and close.

Next, the operation of this embodiment constructed as described above will be described. When an electric acceleration sensor detects a side collision of a vehicle, the collision detection signal is transmitted to a control unit (CP).
U), the collision direction is determined, and the squib 3 is an electric ignition device of the inflator 33a of the side airbag device to be inflated according to the collision direction.
An electric current flows through 3c, the gas generating agent in the inflator 33a is ignited, and the generated gas inflates the airbag 32, pushes and opens the trim cover 42 and deploys it in the vehicle interior,
Protects occupants from secondary collision with the cabin side walls. In addition,
As described above, when the electric ignition method is operating normally, the operation of the mechanical ignition device 37 is regulated by fixing the steel ball 38 by the stopper pin 41a.

When the wire harness 36 disposed on the side of the vehicle body is pulled and cut by a deformable outer plate or the like at the time of a side collision, the power supply to the wiring 36a branched from the wire harness 36 is also cut off. As a result, the magnetized solenoid type stopper 41 is demagnetized.
Therefore, the stopper pin 41a of the solenoid type stopper 41 is retracted by the elastic force of the return spring 41b, and the rolling regulation of the steel ball 38 is released.
8 is rolled outward by the inertia force at the time of collision, and one end of the lever 40 is pushed to rotate.
Of the gas generating agent in the inflator 33b by striking the primer 39 with the hammer 40a provided at the other end. Therefore, even if the wire harness 36 is cut off at the time of collision and the electric ignition method of one of the inflators 33a does not operate, the other inflator 33b is ignited by the mechanical ignition device 37 instead, and the airbag 32 is generated by the generated gas. Can be inflated to protect the occupant.

In this embodiment, a case has been described in which two inflators, an inflator 33a for electrically igniting and an inflator 33b for igniting mechanically, are attached to one airbag 32. However, a dedicated airbag may be attached to each of the inflators 33a and 33b.

In this embodiment, as a means for preventing malfunction when the power supply is turned off (when the ignition switch is turned off), the operation of the mechanical ignition device 37 is prohibited by using a courtesy lamp switch at the time of opening and closing the door. However, as another means for preventing malfunction when the power is turned off, for example, a solenoid-type stopper 41 may be provided by applying a small current that does not impose a load on the battery even after the power is turned off.
May be continuously excited.

In both of the above embodiments, the description has been given of the case where the hybrid ignition system is applied to the ignition system of the side airbag device. However, the ignition system of the airbag device for a frontal collision and the like are almost the same. Can be applied.

[0024]

As described above, in the hybrid ignition system of the airbag device according to the present invention, since the mechanical ignition device is provided in addition to the electric ignition device as the ignition device for the inflator, the electric ignition device is cut by cutting the wire harness. Is inoperable, the inflator can be ignited by the mechanical ignition device, and the operation of the mechanical ignition device is released when the electric wiring to the electric ignition device is cut off in the event of a collision. Since the control means is provided, when the electric ignition device is operable, the operation of the mechanical ignition device is restricted, and malfunction due to an impact such as dropping during assembly work or opening / closing a door after mounting is prevented. be able to.

[Brief description of the drawings]

FIG. 1 is a sectional plan view of a side door showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional plan view of the mechanical ignition device in the first embodiment.

FIG. 3 is a sectional plan view of a side door showing a second embodiment of the present invention.

FIG. 4 is an enlarged sectional plan view of a mechanical ignition device according to a second embodiment.

FIG. 5 is an explanatory diagram showing an arrangement of an acceleration sensor for an airbag device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Side door 13 Inflator 13a Squib (electric igniter) 16 Wire harness 17 Mechanical igniter 18 Steel ball 19 Detonator 20a Hammer 21 Stopper pin 22 Wire 33c Squib (electric igniter) 36 Wire harness 37 Mechanical igniter 41 Solenoid type stopper

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

Claims (1)

(57) [Claims] 1. An airbag device including an electric ignition device for electrically igniting an inflator, wherein the inflator includes a mechanical ignition device for mechanically igniting the inflator using inertial force at the time of collision. The hybrid ignition system for an airbag device, wherein the mechanical ignition device includes an operation restriction unit that releases an operation restriction when an electric wire to the electric ignition device is cut off in a collision.