JPH06144150A - Hybrid ignition system for air bag 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 which protects an occupant from a secondary collision when a vehicle collides.

[0002]

2. Description of the Related Art For example, in a side collision of a vehicle, a side airbag of an airbag device which is inflated and deployed between a side wall of a vehicle interior 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 the same, and is housed in a side door facing the vehicle compartment, an armrest, or the like.

An acceleration sensor for detecting a vehicle collision is, for example, a monocoque in the sensor of an airbag device (see FIG. 5) described in the specification attached to the application of Japanese Patent Application No. 4-10124. The floor tunnel 3 formed on the center line of the floor pan 2 of the body 1 and the side sills 5, 5 formed substantially parallel to the floor tunnel 3 on both sides of the floor pan 2 are connected to the center line of the body. Cross members 6 and 6 provided at right angles to each other are provided. Further, on the floor tunnel 3 provided on the center line of the vehicle body, and at a position on the axis L of the cross members 6 and 6 that connect both side surfaces of the floor tunnel 3 and the side sills 5 and 5, The acceleration sensor 7 is installed as a collision sensor while being fixed by bolts or the like. 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 the vehicle collides with a single collision sensor, and outputs a detection signal to the inflator ( (Not shown), the inflator is ignited, the generated gas inflates the side airbag, and the occupant is protected from a secondary collision with a side wall of the passenger compartment or the like.

[0004]

However, when the inflator is ignited by transmitting a detection signal when a collision is detected like the acceleration sensor 7 of the airbag device described above, the acceleration sensor 7 and the inflator ignition device. Directly to or from a computer (control device)
It is necessary to connect the wiring indirectly via the above. Therefore, when the acceleration sensor 7 is arranged in a rigid body portion such as a vehicle body frame, and the inflator and the air bag are arranged in a side door (not shown), the acceleration sensor and the power source and the inflator are A wire harness that connects to the ignition device will be disposed on the side of the vehicle body.
Therefore, at the time 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, there is provided a plurality of circuits or a structure for firmly protecting the wire harness itself. It becomes necessary, and there is a problem that the cost, space, weight, etc. are increased.

The present invention has been made in view of the above circumstances, and provides an ignition system for an air bag device having means for mechanically igniting an ignition device of an inflator when a wire such as a wire harness is cut. It is intended to be provided.

[0006]

As a means for solving the above problems, a hybrid ignition system for an airbag apparatus according to the present invention is an airbag apparatus equipped with an electric ignition device for electrically igniting an inflator. The inflator includes a mechanical ignition device that mechanically ignites the inflator by utilizing inertial force at the time of collision, and the mechanical ignition device releases the operation regulation when the electric wiring to the electric ignition device is disconnected at the time of 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, the mechanical ignition device that mechanically ignites the inflator by utilizing the inertial force at the time of collision is provided, and the mechanical ignition device is provided with the operation restricting means so as to be provided at the time of collision. When the electric wiring to the electric ignition device is cut, the regulation by the operation regulation means is released,
The mechanical ignition device becomes operable and operates by the inertial force at the time of collision to mechanically ignite the inflator, and the generated gas 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 for a side airbag device will be described below with reference to FIGS.

1 and 2 show a first embodiment of the present invention, in which a back plate 14 for an airbag 12 and an inflator 13 is provided in a side door 11 of a vehicle.
The wire harness 16, which is attached to the door inner panel 15 by being integrally assembled with the vehicle body and which carries an ignition signal and an ignition current at the time of collision detection, is provided on the rigid body portion of the body (not shown), It is stretched between a control device (CPU) that determines a collision direction and the like and an inflator 13 provided on a side door.

A mechanical ignition device 17 is provided outside the vehicle body of the inflator 13 (upper side in FIG. 1). This mechanical ignition device 17 divides the inside of the box-shaped case into two chambers in the longitudinal direction of the vehicle body, and accommodates a steel ball 18 rollably in one of the chambers, as shown in the sectional plan view of FIG. On the other hand, a detonator 19 for igniting the inflator 13 is provided on the other side so that a gas generating agent (not shown) in the inflator 13 can be ignited. Further, an opening 17b is formed in the partition walls 17a of both chambers toward the outer side of the vehicle body, and a lever 20 is inserted into the opening 17b so that the lever 20 can be horizontally rotated about its center as a fulcrum. A hammer 20a is attached to the tip of the lever 20 on the chamber side (right side in FIG. 2) where the detonator 19 is provided. When the steel ball 18 rolls in the vehicle body outward direction due to inertial force at the time of collision and pushes one end side of the lever 20 outwardly, the lever 20 rotates clockwise in FIG. The hammer 20a attached to the other end strikes the detonator 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 a shock or the like at the time of assembly or opening / closing of the side door. The steel ball 18 housed in one of the compartments is inserted into the apparatus from the front side of the vehicle body to regulate the rolling of the steel ball 18 in the vehicle body outer direction (upward in FIG. 2). A wire 22 such as a piano wire, which has a high tensile strength and is hard to stretch, is connected to the end of the stopper pin 21, and the wire 22 is also provided in the side door 11. Is disposed along with the front end extending from the side door 11 and fixed to the body side.

In FIG. 1, reference numeral 23 is a trim cover that covers the inside of the airbag 12 housed in the side door 11 so as to be openable and closable.

Next, the operation of this embodiment configured as described above will be described. When a side collision of the vehicle is detected by the electric acceleration sensor, the collision detection signal is sent to the control device (CP).
U), the collision direction is indexed, and a signal current flows from this control device to the inflator 13 of the side airbag device to be inflated according to the indexed collision direction. The gas generating agent in the inflator 13 is ignited by flowing into a squib (electric detonator) 13a which is an ignition device. Then, the airbag 12 is inflated by the gas generated from the inflator 13, and the inflating airbag 12 pushes the trim cover 23 open and deploys it in the passenger compartment to protect the occupant from a secondary collision with a side wall of the passenger compartment or the like. . When the electric ignition method is operating normally as described above, the operation of the mechanical ignition device 17 is restricted by fixing the steel ball 18 with the stopper pin 21.

When a side collision occurs, when the wire harness 16 disposed on the side of the vehicle body is pulled and cut by an outer plate or the like deformed by the collision vehicle, the wire harness 16 is stretched along the wire harness 16. Wire 22
Since its tensile strength is large and it is difficult to stretch, 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 from the mechanical ignition device 17. Therefore, the mechanical ignition device 17
Of operation of the steel ball 1 by the stopper pin 21
When the rolling regulation of No. 8 is released, the steel ball 18 rolls in the outer side direction of the vehicle body by the inertial force at the time of collision, and pushes one end of the lever 20 in the outer side direction (rolling direction). As a result, the hammer 20a attached to the other end of the lever 20 which rotates about the center as a fulcrum strikes the detonator 19 and ignites the inflator 13. Therefore, even if the wire harness 16 is cut at the time of a collision and the electric ignition method does not work, the mechanical igniter 17 ignites the inflator 13 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 which an airbag 32 and two inflators 33a and 33b are integrated with a backup plate 34 in a side door 31 of a vehicle. The wire harness 36, which is attached to the door inner panel 35 and supplies an ignition current when a collision is detected, detects a collision direction from a collision detection signal of an electric acceleration sensor (not shown) provided in a rigid body portion of the body. It is stretched between a control device (CPU) for determining the above, and one inflator 33a provided on the side door. The inflator 33a also includes a squib 33c that is an electric ignition device.
An electric 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). For example, as shown in the sectional plan view of FIG. 4, the mechanical ignition device 37 accommodates a steel ball 38 rollably inside the box-shaped case inside the vehicle interior, and a lever 40 on the outside of the vehicle body. , Is disposed so as to be horizontally rotatable around a fulcrum as a fulcrum, and a detonator 39 is provided inside the vehicle body of the lever 40 so as to ignite a gas generating agent (not shown) in the inflator 33b. . Further, the mechanical ignition device 37 includes a solenoid stopper 41 as a safety device for preventing malfunction due to 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, the stopper pin 41a compresses the return spring 41b, and projects into the case of the mechanical ignition device 37. Rolling of the steel balls 38 inside the steel balls 38 toward the outer side of the vehicle body is restricted. And this solenoid type stopper 41
As the power source for exciting the other inflator 3
Wire harness 36 connected to squib 33c of 3a
A wire 36a branched from a position extremely close to the inflator 33a is connected.

The solenoid type stopper 41 is
In order to prevent erroneous operation due to impact when the door is opened or closed while the ignition switch is OFF, the switch for the courtesy lamp that lights up when the door is opened is linked with ON / OFF, and the delay circuit by the capacitor (door closing operation) After that, the solenoid type stopper 41 is excited when the door is opened and closed to regulate the operation of the mechanical ignition device 37.

In FIG. 3, reference numeral 42 is a trim cover that covers the inside of the airbag 32 housed in the side door 31 so as to be openable and closable.

Next, the operation of this embodiment configured as described above will be explained. When the electric acceleration sensor detects a side collision of the vehicle, the collision detection signal is sent to the control device (CP).
S), which is an electric ignition device for the inflator 33a of the side airbag device, which is to be inflated according to the collision direction.
3c causes a current to flow, the gas generating agent in the inflator 33a is ignited, the generated gas inflates the airbag 32, pushes the trim cover 42 open, and deploys it in the passenger compartment.
Protects occupants from secondary collisions with the vehicle interior side walls. In addition,
As described above, when the electric ignition method is normally operating, the mechanical ignition device 37 is restricted in operation by fixing the steel ball 38 by the stopper pin 41a.

At the time of a side collision, when the wire harness 36 arranged on the side of the vehicle body is pulled and cut by a deforming outer plate or the like, the electric current to the wiring 36a branched from the wire harness 36 is also cut off. As a result, the excited 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 to release the rolling regulation of the steel ball 38, and the steel ball 3
8 rolls toward the outer side of the vehicle body due to the inertial force at the time of a collision, and one end side of the lever 40 is pushed and rotated.
Hammer iron 40a provided at the other end of the hammer strikes the detonator 39 to ignite the gas generating agent in the inflator 33b. Therefore, even if the wire harness 36 is cut at the time of a collision and the electric ignition method of the one inflator 33a does not operate, the mechanical igniter 37 instead ignites the other inflator 33b, and the generated gas causes the airbag 32 to ignite. Can be inflated to protect the occupant.

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

Further, in this embodiment, as a means for preventing a malfunction when the power is off (when the ignition switch is off), the operation of the mechanical ignition device 37 is prohibited at the time of opening / closing the door by using the courtesy lamp switch. However, as another means for preventing a malfunction when the power is turned off, for example, a solenoid-type stopper 41 is applied by applying a minute current that does not burden the battery even after the power is turned off.
May continue to be excited.

Although the hybrid ignition system is applied to the ignition system of the side airbag device in both of the above embodiments, the same applies to the ignition system of the airbag device for frontal collision. Can be applied.

[0024]

As described above, in the hybrid ignition system for an airbag device according to the present invention, since the mechanical ignition device is provided as the ignition device for the inflator in addition to the electric ignition device, the wire harness is cut and the electric ignition device is cut off. Even if the inoperator becomes inoperable, the inflator can be ignited by the mechanical ignition device, and this mechanical ignition device is released from the operation regulation when the electric wiring to the electric ignition device is cut at the time of a collision. Since the control means is provided, the operation of this mechanical ignition device is restricted when the electric ignition device is operable, and it is prevented from malfunctioning due to impact such as dropping during assembly work or opening / closing the door after installation. be able to.

[Brief description of drawings]

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

FIG. 2 is an enlarged cross-sectional plan view of the mechanical ignition device according to 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 the arrangement of acceleration sensors for an airbag device.

[Explanation of symbols]

 11 Side Door 13 Inflator 13a Squib (Electrical Ignition Device) 16 Wire Harness 17 Mechanical Ignition Device 18 Steel Ball 19 Detonator 20a Hammer Iron 21 Stopper Pin 22 Wire 33c Squib (Electric Ignition Device) 36 Wire Harness 37 Mechanical Ignition Device 41 Solenoid Stopper

Claims (1)

[Claims] 1. An airbag device including an electric ignition device for electrically igniting an inflator, wherein the inflator includes a mechanical ignition device that mechanically ignites the inflator by utilizing inertial force at the time of collision, A hybrid ignition system for an air bag device, wherein the mechanical ignition device includes an operation restricting means for canceling the operation restriction when the electric wiring to the electric ignition device is cut at the time of a collision.