JPH06286569A - Air bag system for vehicle - Google Patents

Abstract

PURPOSE:To quickly expand an air bag and effectively mitigate a shock applied on a crew by providing an elastic member crossing an exhaust hole on the middle territory of the exhaust hole of an air bag, and fixing respective end parts to the air bag. CONSTITUTION:For example, four slender exhaust holes 5 are formed on the back face side 2 of an air bag 1, and sheet-like elastic members 6 of rubber and the like are provided on the exhaust holes 5. In this case, the elastic member 6 crosses the exhaust hole 5 on the middle territory in the lengthwise direction of the exhaust hole 5. The elastic member 6 is fixed to the air bag 1 at respective end parts by sewing, adhesive, or the like. When the air bag 1 is not expanded by gas pressure, the exkaust holes are restrsained with the elastic members, and not so largely opened. In the early stage of beginning of expansion, the size of the exhaust holes are small, and hence the air bag 1 is quickly expanded. When the pressure reaches the maximum value, the elastic members deform elastically and extend, and hence the exhaust holes largely open.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air bag for inflating an air bag between an occupant and an indoor part in front of the occupant to prevent the occupant from directly contacting the indoor part in a vehicle collision. It relates to a bag system.

[0002]

2. Description of the Related Art It is well known in the prior art to mount an airbag system for restraining the occupant by restraining the movement of the occupant by an inflated airbag when the vehicle collides with a vehicle such as an automobile (for example, an actual flat tire). No. 1-150155).

In this type of airbag system, a vehicle collision is detected by a sensor that detects the vehicle deceleration at the time of a collision, and the detection signal is used to operate an inflator provided in front of the occupant to generate gas. The gas is sent into the airbag that has been folded so far to inflate the bag, and the occupant is received by the airbag to protect the occupant. An exhaust hole is formed in such an airbag, and by discharging a part of the gas in the airbag from the exhaust hole, when an occupant hits the airbag, the repulsion of the occupant is mitigated, and the air bag for the occupant is restrained. I try to absorb the shock.

[0004]

Such an air bag is configured to complete inflation in an extremely short time after the sensor detects a collision, for example, a short time of about 30 msec, and reliably receive the occupant. Has been done. However, since the exhaust hole is formed in the airbag as described above, the gas constantly flows out from the exhaust hole until the gas is sent from the folded state of the bag until the inflation is completed. To configure the airbag system so that the time from the start of inflation of the bag to the completion of inflation is extremely short as described above, the total cost is high and the airbag system is expensive. I couldn't avoid the drawback.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide an airbag system for a vehicle which can reduce the cost as compared with the conventional one.

[0006]

In order to achieve the above object, the present invention provides a sensor for detecting a collision of a vehicle, an inflator which operates in response to the detection signal to generate gas, and the gas which is fed to expand the gas. In an air bag system for a vehicle, the air bag is provided with an elongate exhaust hole for exhausting gas inside the air bag, and the exhaust hole has an intermediate region in a longitudinal direction thereof. An airbag system for a vehicle is proposed in which an elastic member that traverses the exhaust hole is provided so as to traverse the longitudinal direction, and each end of the elastic member is fixed to the airbag.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing an airbag 1 of an airbag system according to the present invention. This airbag 1
Is made of a non-breathable flexible material, for example, a bag-shaped nylon cloth whose inside is coated with rubber. A gas inflow hole 3 is formed in the center of the back surface 2 of the airbag 1.

The above-described airbag 1 is arranged in a state of being folded in front of an occupant in a vehicle compartment. For example, although not shown in the drawing, the inflator is arranged on a support plate provided on the central hub portion of the steering wheel located in front of the driver's seat in the passenger compartment, and the airbag 1 has the gas inflow hole 3 of the inflator. The peripheral portion of the gas inflow hole 3 is fixed to the support plate in a state of being fitted to. The airbag 1 is stored in a cover attached to the support plate in a folded state.

Since such a mounting structure of the airbag 1 is well known in the art, as described in detail in, for example, Japanese Utility Model Laid-Open No. 1-150155, further description will be omitted.

The airbag system according to the present invention has, in addition to the airbag 1 and the inflator described above, a sensor (not shown) arranged at a proper position on the vehicle body, and this sensor detects a collision of an automobile. Upon detection, the detection signal causes the inflator to operate and generate, for example, nitrogen gas. The gas thus generated is sent into the airbag 1 through the gas inflow hole 3 shown in FIG. 1, whereby the airbag 1 starts inflating, and the pressure thereof causes the above-mentioned cover surrounding the airbag 1 to be inflated. To break. Then, the airbag 1 largely inflates between the steering wheel and the occupant, and the front surface side 4 receives the body of the occupant, particularly the face thereof, and protects the occupant.

When the inflated airbag 1 receives an occupant, it is necessary to discharge a part of the gas in the airbag 1 for the purpose of reducing the impact on the occupant. For this reason,
In the present invention, as illustrated in FIGS. 1 to 3, an appropriate number of four elongate exhaust holes 5 in the illustrated example are formed on the back side 2 of the airbag 1. It is configured so that the gas inside the airbag 1 is discharged through the air bag 5. At that time, a sheet-like elastic member 6 made of, for example, rubber or soft synthetic resin is provided in these exhaust holes 5.

As can be seen from FIGS. 2 and 3 showing one of these exhaust holes 5 in an enlarged manner, the exhaust hole 5 is formed in an elongated slot shape, and the elastic member 6 is formed in the longitudinal direction of the exhaust hole 5. In the intermediate region of X, the exhaust hole 5 is crossed so as to cross the longitudinal direction X thereof. Each end of the elastic member 6 is fixed to the airbag 1 by sewing or an adhesive. Reference numeral 7 indicates the sewn portion. Since the elastic member 6 is located in the longitudinal intermediate region of the exhaust hole 5, the elastic member 6 covers only a part of the exhaust hole 5, and the exhaust hole portions 5a on both sides of the elastic member 6 are closed by the elastic member 6. It will not be done.

When no gas has been sent to the airbag 1 and therefore the airbag 1 is not inflated by the gas pressure, the exhaust hole 5 is restrained by the elastic member 6,
There is no large opening. Is the exhaust hole 5 closed?
Alternatively, the opening area is extremely small as shown in FIGS.

FIG. 4 is a diagram showing an example of changes in the internal pressure of the airbag 1 when gas is fed into the airbag 1 and the airbag 1 is inflated. FIG. 4 is a graph in which the vertical axis represents the pressure inside the airbag and the horizontal axis represents time. The solid line A shows the change in the internal pressure of the airbag 1 shown in FIGS. 1 to 3.

In FIG. 4, at time t ₁ , the airbag 1 is
The internal pressure of P shows a peak value P ₁ , which is the pressure when the airbag 1 fed with gas breaks the cover as described above. After breaking the cover, the pressure in the airbag is reduced once, according to the amount of gas fed into the inside is increased, the pressure in the airbag is increased again, the maximum value P ₂ at the time indicated by t ₂ Then, the inflation of the airbag 1 is completed.

When the pressure inside the airbag 1 rises again after the cover is broken, a tensile force is applied to the airbag 1, and the magnitude thereof increases with the inflation of the airbag 1. When such a tensile force acts on the airbag 1, the exhaust hole 5 formed therein expands so as to expand the width of the hole 5 in a direction orthogonal to the longitudinal direction X while tensilely deforming the elastic member 6. .

Since the air bag 1 is made of the rubber-coated cloth as described above, the air bag 5 does not largely undergo tensile deformation, but the exhaust hole 5 is expanded by the tensile force applied to the air bag 1. Thus, the maximum value P ₂ the pressure of the air bag 1 is at time t ₂
The exhaust hole 5 has a large opening as shown in FIGS. 5 and 6. At this time, the elastic member 6 elastically deforms and expands, so that the expansion of the exhaust hole 5 is not hindered.

As described above, the exhaust hole 5 is substantially closed or the size thereof is kept small immediately after the airbag 1 breaks the cover.
The air bag 1 continues to inflate, and the exhaust hole 7 greatly expands just before the internal pressure reaches the maximum value P ₂ . With the expansion of the airbag 1 after the cover is broken, the gas inside flows out from the exhaust hole portion 5a. At this time, in the initial stage where the expansion starts, the size of the exhaust hole 5 is small as described above, so that the amount of gas flowing out from the exhaust hole 5 is extremely small. Therefore, the airbag 1 inflates rapidly and completes the inflation in a very short time. Therefore, the occupant can be reliably received by the airbag 1.

On the other hand, as the inflation of the airbag 1 progresses and the exhaust hole 5 expands largely immediately before the internal pressure reaches the maximum value P ₂ (FIGS. 5 and 6), the inside of the airbag 1 passes through this. The amount of gas flowing out increases. Therefore, when the occupant hits the inflated airbag 1,
The pressure inside the airbag 1 does not become too high, and even after the occupant hits the airbag 1, the gas inside the airbag 1 is effectively released through the expanded exhaust hole 5, so It is possible to reliably reduce the impact on the.

As described above, the amount of gas discharged from the airbag 1 increases in accordance with the increase of the gas pressure inside the airbag 1, so that the inflation of the airbag 1 is completed quickly and the occupant of the airbag 1 is inflated. The impact on the can be effectively softened.

In the embodiment shown in FIGS. 1 to 3, the exhaust hole 5 is formed in a slot shape, but its form can be selected appropriately. For example, as shown in FIG. 7, the exhaust hole 5 may have a slit shape that is closed when the airbag 1 is not inflated. Further, as shown in FIG. 8, the exhaust hole 5 may be formed in an appropriate shape. The point is that the exhaust holes have an elongated shape.

[0023]

According to the structure described in claim 1, when the airbag is quickly inflated and the occupant is received by the airbag, the impact given to the occupant can be effectively mitigated, and The structure of the airbag system is simple, and there is an advantage that the cost can be reduced as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a perspective view of an airbag.

FIG. 2 is an enlarged perspective view of an exhaust hole and an elastic member provided in the airbag.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a graph showing an example of changes in the internal pressure of the airbag.

FIG. 5 is a perspective view similar to FIG. 2 when the airbag is inflated.

FIG. 6 is a perspective view similar to FIG. 1 when the airbag is inflated.

FIG. 7 is a perspective view similar to FIG. 2, showing another embodiment of exhaust holes.

FIG. 8 is a perspective view similar to FIG. 2, showing yet another embodiment of an exhaust hole.

[Explanation of symbols]

 1 Airbag 5 Exhaust hole 6 Elastic member X Longitudinal direction

Claims (1)

[Claims] 1. A sensor for detecting a collision of a vehicle, and an inflator which operates by the detection signal to generate gas.
An air bag system for a vehicle, comprising an air bag that is inflated by feeding the gas, wherein an elongated exhaust hole for discharging the gas inside the air bag is formed in the air bag, and the length of the exhaust hole is long. An airbag system for a vehicle, comprising: an elastic member that traverses the exhaust hole so as to traverse the longitudinal direction in an intermediate region in the direction; and each end of the elastic member is fixed to the airbag.