JP5034239B2 - Pedestrian airbag device - Google Patents

Description

  The present invention relates to a pedestrian airbag apparatus having an airbag that inflates along an outer surface of a vehicle body.

2. Description of the Related Art A pedestrian airbag device is known in which an airbag is inflated along an outer surface of a vehicle body to receive a pedestrian or the like (pedestrian, bicycle occupant, etc.). Japanese Patent Application Laid-Open No. 2003-306097 describes that a release valve that opens when the gas pressure in the airbag exceeds a predetermined pressure is provided as the airbag device for a pedestrian.
JP 2003-306097 A

  When a pedestrian airbag is inflated and deployed in front of or on the side of the driver's seat, if the airbag remains inflated for an excessively long period of time, the inflated airbag blocks the view from the driver's seat. There is a danger of losing control of the vehicle. For this reason, after a certain amount of time has passed since the airbag has been inflated, it is desirable to reduce the volume of the airbag by letting gas flow out of the airbag to ensure visibility from the driver's seat.

  In the pedestrian airbag device disclosed in Japanese Patent Laid-Open No. 2003-306097, the release valve does not open until the gas pressure in the airbag exceeds a predetermined pressure (that is, gas does not flow out from the airbag). The airbag may remain inflated for an excessively long period of time.

  The present invention does not open the valve following the internal pressure of the airbag, but communicates between the inside and outside of the airbag when a predetermined time has elapsed since the start of the operation of the inflator. It is an object of the present invention to provide a pedestrian airbag device configured to accommodate.

A pedestrian airbag apparatus according to the present invention (Claim 1) is a pedestrian airbag apparatus having an airbag that inflates along an outer surface of a vehicle body and an inflator that releases a gas for inflating the airbag. In order to ensure the driver's field of view, when the predetermined time has elapsed since the start of the operation of the inflator, it is activated to connect the inside of the airbag with the outside of the airbag, and exhausts the gas in the airbag. The communication device includes a communication device that forms a communication hole for reducing the volume of the airbag, the communication device is an explosion device that ignites and pierces the airbag, and the explosion device starts operating the inflator. When 250 to 500 mSec elapses, the air bag is exploded and the airbag is perforated .

In the pedestrian airbag device of the present invention, when 250 to 500 mSec has elapsed since the start of the inflator operation, the communication device is activated and the inside and outside of the airbag communicate. Until this 250 to 500 mSec elapses, the communication device does not communicate between the inside and outside of the airbag, the airbag is rapidly inflated by the gas from the inflator, and the internal pressure of the airbag is ensured. A pedestrian or the like is received by the inflated airbag.

When 250 to 500 mSec has elapsed since the start of the operation of the inflator , the communication device is activated, and a communication hole is formed to communicate between the inside and outside of the airbag, so that the gas in the airbag is brought out of the airbag through this communication hole. Outflow and volume reduction of the airbag. Therefore, this airbag prevents the view from the driver's seat from being obstructed for an excessively long period.

In the present invention, RendoriSo location is a detonator drilling airbag detonated.

  Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a perspective view of an automobile provided with a pedestrian airbag device according to an embodiment, FIG. 2 is a perspective view of the automobile of FIG. 1 when the airbag is inflated, and FIG. 3 is III of FIG. FIG. 4 is an enlarged sectional view taken along line -III, FIG. 4 is an enlarged sectional view taken along line IV-IV in FIG. 2, and FIG. 5 is an enlarged view of a case portion for storing an airbag in FIG. FIG. 5 (a) shows the state before the explosion of the detonator, and FIG. 5 (b) shows the state after the detonation.

  As shown in FIG. 1, the automobile 1 is a four-door sedan in this embodiment, but the present invention is not limited to a specific vehicle form. A pedestrian airbag device 4 is installed at the rear of the hood 3. As shown in FIG. 2, when the airbag 5 of the pedestrian airbag device 4 is inflated, at least a part of the cowl louver 2, the windshield 6, and the left and right A pillars 7 are covered with the airbag 5.

  As shown in FIGS. 3 to 5, the pedestrian airbag device 4 includes a case 8 for storing the folded airbag 5, an inflator 9 for inflating the airbag 5, and an air for the hood 3. A lid 10 that closes the bag passage opening 3a, and an initiation device 20 as a communication device that communicates the inside and outside of the airbag 5 are provided.

  The case 8 has a long box shape extending in the vehicle body width direction. The case 8 includes a bottom portion 8a, a front wall portion 8b, a rear wall portion 8c, and left and right end walls (not shown), and an upper portion is open.

  In this embodiment, a gas outlet 8e (FIG. 5) is provided in the rear wall portion 8c facing the rear side of the vehicle for allowing the gas flowing out from the airbag 5 to flow out of the case 8.

  A folded body of the airbag 5 is disposed in the case 8, and a base end side of the airbag 5 is fixed to the case 8. The inflator 9 is also disposed in the case 8 (in the airbag 5 in this embodiment) and fixed to the case 8. A wiring (not shown) for energization to the initiator (not shown) of the inflator 9 is drawn out of the airbag 5 and the case 8 and connected to a control circuit (not shown).

  In this embodiment, on the base end side of the airbag 5, when the airbag 5 is inflated, a portion of the rear wall 8 c of the case 8 that faces the gas outlet 8 e is disposed in the airbag 5. A gas outlet 5a (FIG. 5) for allowing gas to flow out of the airbag 5 is provided. The gas outlets 5a and 8e have substantially the same size and shape.

  Although the detailed illustration is omitted, in the present embodiment, the detonator 20 has a housing of a size and shape capable of closing the gas outlets 5a and 8e, a glaze accommodated in the housing, and the glaze. And an initiator for detonation. A pair of flange portions 20a and 20b project (peripherally) from the side peripheral portion of the housing so as to sandwich the peripheral portions of the gas outlets 5a and 8e from the inside and outside of the case 8.

  When installing the detonator 20, as shown in FIG. 5, the peripheral portion of the gas outlet 5a is overlapped with the peripheral portion of the gas outlet 8e from the inside of the case 8, and the housing of the detonator 20 is placed inside thereof. Fit. Then, the housing is fixed so as to sandwich the peripheral portions of the gas outlets 5a and 8e that overlap each other between the flange portions 20a and 20b on the peripheral side of the housing. As a result, the gas outlets 5a and 8e are integrated with each other and are sealed by the housing of the detonator 20.

  The flange portions 20a and 20b may be formed by fitting the housing into the gas outlets 5a and 8e and then caulking and deforming the side peripheral portion of the housing, and are provided separately from the housing. It may be attached later. The flange portions 20a and 20b may be made of elastically deformable rubber, synthetic resin, or the like, and the housing may be fitted into the gas outlets 5a and 8e while elastically deforming them.

  However, the installation structure of the detonator 20 and the closed structure of the gas outlets 5a and 8e are not limited to the above-described configuration. For example, although not illustrated, the gas outlets 5a and 8e are closed by a lid member provided separately from the detonator 20, and the lid member is closed by the initiation force of the initiator 20 with the gas outlets 5a and 8e. You may comprise so that it may detach | leave from.

  A wiring for energizing the initiator of the detonator 20 is connected to the control circuit. When it is detected or predicted that the vehicle has collided with a pedestrian or the like by various sensors provided in the vehicle, the control circuit first activates the initiator of the inflator 9 and starts the initiator of the inflator 9. The initiator of the detonator 20 is activated after a predetermined time has elapsed since activation.

  In the present invention, it is preferable that the time from when the initiator of the inflator 9 is activated to when the initiator of the detonator 20 is activated is about 250 to 500 mSec.

  The lid 10 is provided with a hinge 11 on the rear edge side of the vehicle body, and the hinge 11 is bolted to a rear edge side of the opening 3a of the hood 3 (a protruding piece 3t protruding from the rear edge of the opening 3a). And so on. When the airbag 5 is inflated, the lid 10 is configured to open while rotating backward as indicated by an arrow θ in FIG. 3 with the hinge 11 as a base point. The front edge side of the lid 10 is fastened to the vehicle body on the front edge side of the opening 3a by locking means (not shown) such as a clip. The locking means is configured to release the locking when the lid 10 is released by being pushed by the airbag 5.

  Next, the action | operation of the airbag apparatus 4 for pedestrians of this structure is demonstrated.

  When the sensor detects or predicts that the vehicle equipped with this pedestrian airbag device 4 collides with a pedestrian or the like, the control circuit first activates the initiator of the inflator 9 from the inflator 9. Gas spouts out. The airbag 5 starts to expand due to the gas ejected from the inflator 9, and the airbag 5 is deployed along the outer surface of the vehicle body as shown in FIG. After a predetermined time has elapsed since the initiator of the inflator 9 is started, the initiator of the detonator 20 is started by the control circuit. As a result, the glaze in the housing of the detonator 20 is detonated, the housing is ruptured, and the gas outlets 5a and 8e are opened as shown in FIG. 5 (b).

  In the pedestrian airbag device 4, the gas outlets 5 a and 8 e are closed until a predetermined time has elapsed since the operation of the inflator 9 is started. 5 is rapidly inflated and the internal pressure of the airbag 5 is secured. A pedestrian or the like is received by the inflated airbag.

  When a predetermined time (about 250 to 500 mSec) elapses after the inflator 9 starts operating, the initiation device 20 is ruptured and the gas outlets 5a and 8e are opened, so that the gas in the airbag 5 is discharged to the gas outlet. The air bag 5 flows out of the airbag 5 (in this embodiment, further out of the case 8) through 5a and 8e, and the volume of the airbag 5 is reduced. This prevents or suppresses the front view of the driver's seat of the vehicle from being obstructed by the airbag 5.

  The above embodiment shows an example of the present invention, and the present invention is not limited to the above embodiment.

  For example, in the above embodiment, the gas outlet 5a (and 8e) is provided in the airbag 5 (and the case 8) in advance, and the gas outlet 5a is closed by the detonator 20, and the detonator 20 is ruptured. The gas outlet 5a is thus opened, but this gas outlet is omitted, and a hole is opened in the airbag 5 by the initiation force of the initiation device 20 so that the inside and outside of the airbag 5 communicate with each other. May be. In the present invention, the inside and outside of the airbag may be communicated with each other by means other than the initiation force of the initiation device.

It is a perspective view of the car provided with the air bag device for pedestrians concerning an embodiment. It is a perspective view of the motor vehicle of FIG. 1 at the time of airbag expansion. It is the III-III line expanded sectional view of FIG. It is the IV-IV line expanded sectional view of FIG. It is a figure which shows the communication structure inside and outside an airbag.

Explanation of symbols

1 Car 2 Cowl Top 3 Bonnet Hood 3a Opening 4 Pedestrian Airbag Device 5 Airbag 5a Gas Outlet 8 Case 8a Bottom 8b Front Wall 8c Rear Wall 8e Gas Outlet 9 Inflator 10 Lid 20 Explosive Device

Claims (1)

In a pedestrian airbag apparatus having an airbag that inflates along the outer surface of the vehicle body and an inflator that releases a gas for inflating the airbag.
In order to secure the driver's field of view, when the predetermined time has elapsed since the start of the operation of the inflator, the driver is activated to communicate the inside of the airbag with the outside of the airbag, and the gas in the airbag is exhausted to It has a communication device that forms a communication hole that reduces the volume of the airbag ,
The communication device is a detonator that detonates and pierces the airbag,
The initiating device explodes and perforates the airbag when 250 to 500 mSec has elapsed since the operation of the inflator has started .

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