JPH04303050A - Automotive air bag structure - Google Patents

Abstract

PURPOSE:To provide an automobile air bag structure that is favorably applicable to such a vehicle, where a crash space of an engine room or the like is almost none in the front of a car body in front of an assistant driver's seat as in a commercial car and, what is more, makes proper restraint giveable to a person in this seat. CONSTITUTION:This air bag structure is installed in front of an assistant driver' s seat of an automobile, and expansion of an air bag 6 is set so as to be finished just after a collision, thereby restraining a rider in the assistant driver's seat, who moves forward even after a body front has collapsed to the full, therefore immediately after the car crash, an air bag unit 3 is once moved toward the body rearward together with a dashpanel 9 by a bracket 10, and in succession, the air bag unit 3 is moved toward the body front by means of a cutoff of a connecting pin 11 connecting the bracket 10 and an air bag unit 13 and action of an energy storage means 8, thus restraint against the rider at the assistant driver's seat is eased to some extent.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an airbag structure for automobiles, and is particularly suitable for application to vehicles such as commercial vehicles that have almost no crash space such as an engine room in the front of the vehicle body in front of the passenger seat. Regarding the structure of airbags for automobiles.

0002

2. Description of the Related Art In recent years, airbag devices have been increasingly installed in automobiles to protect occupants. This airbag system uses an airbag housed in an airbag unit installed at the front of the vehicle to instantly inflate in the passenger compartment due to the impact of a collision, restraining the occupant's upper body. On the passenger side, each device is installed between the dash panel and the instrument panel. and,
Since the distance between the passenger and the airbag unit on the passenger seat side is large, the inflation rate of the airbag on the passenger seat side is generally set to be larger than that on the driver's seat side.

0003

[Problems to be Solved by the Invention] Up until now, airbag devices have been mainly installed in passenger cars, but there are also increasing requests for installation in commercial vehicles and the like. However, when an airbag device is installed in a commercial vehicle or the like, there is a possibility that the restraint force exerted on the occupant by the airbag becomes excessive, especially on the passenger seat side.

First, looking at the structure of commercial vehicles, most of them are cab-over type in which the engine is mounted below the driver's seat, and there is almost no crash space at the front of the vehicle body in front of the passenger seat, so in the event of a collision, The dash panel moves directly to the rear of the vehicle, and especially on the passenger seat side, there is nothing between the dash panel and the occupant that prevents the dash panel from moving backwards.

[0005] Regarding the function of the airbag, it is necessary to set the restraining force of the airbag on the occupant so that it does not become excessive. Passenger car-type vehicles have a crash space called the engine room at the front of the vehicle body, so the amount of receding of the dash panel due to the collapse of the front of the vehicle body during a collision is relatively small. In a vehicle, there is almost nothing to prevent the dash panel from retreating, so the amount it retreats is large. Therefore, as the dash panel recedes during a collision, the airbag unit installed on the dash panel approaches the front passenger, causing damage to both passengers. The distance becomes smaller. As a result,
Due to the approach of the airbag unit to the occupant, there is a possibility that the restraint force exerted by the airbag on the occupant becomes excessively large.

In other words, the inflation of the airbag is generally set to complete immediately after a collision, and even after the front part of the vehicle body has collapsed, it restrains the front passenger seat occupant who is moving forward. As mentioned above, in car-type vehicles, the distance between the front passenger and the airbag unit is large, so the gas pressure introduced into the airbag is increased to instantly deploy the airbag with a large volume immediately after a collision. Although it is necessary to restrain the occupant moving forward, when the airbag unit approaches the occupant side due to the collapse of the front part of the vehicle body after a collision, this airbag unit is moved a considerable amount to the rear of the vehicle. Considering that the distance between the driver and the occupant who continues to move forward is becoming smaller, it is preferable to reduce the restraining force of the airbag on the occupant after the front of the vehicle has completely collapsed. It is desired to devise an airbag structure that can solve both of these problems.

The present invention has been made in view of the above circumstances, and can be preferably applied to vehicles such as commercial vehicles that have almost no crash space such as an engine compartment in the front of the vehicle body in front of the passenger seat. An object of the present invention is to provide an airbag structure for an automobile that can provide an appropriate restraining force to an occupant.

[0008]

[Means for Solving the Problems] The present invention moves an airbag unit provided in front of a passenger seat to inflate and deploy an airbag to the rear following the movement of the front part of the vehicle body to the rear of the vehicle body. The present invention is characterized in that a restraining force relieving means is provided for subsequently returning the airbag unit to the front of the vehicle body and relieving the restraint force exerted by the airbag.

The restraining force relieving means is provided between the front portion of the vehicle body and the airbag unit to connect them, and is configured to move the front portion of the vehicle body toward the rear of the vehicle body so as to move the airbag unit. It is preferable to include a connecting means that moves the unit rearward and separates the front portion of the vehicle body and the airbag unit under a set load or more.

[0010] It is also preferable that the restraining force relieving means includes energy storage means for accumulating a restoring force for returning the airbag unit to the front of the vehicle body when the airbag unit moves toward the rear of the vehicle body.

Furthermore, the energy storage means has a U-shaped cross section, one end of which is attached to a vehicle body side member insulated from the front of the vehicle that is moved toward the rear of the vehicle, and the other end of which is connected to the airbag unit. It is preferable that the support plate is comprised of a support plate.

0012

[Function] To explain the function of the present invention, the restraining force alleviation means moves the airbag unit rearward following the movement of the front part of the vehicle body to the rear of the vehicle body, and then returns the airbag to the front of the vehicle body. From immediately after the collision until the front of the vehicle is completely collapsed, the airbag unit can approach the occupant and exert sufficient restraint force. By moving away from the vehicle, the restraining force of the airbag on the occupant, which would be excessive if the vehicle remained close to the vehicle, can be alleviated, and the restraining force of the airbag on the occupant over time can be preferably set.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of the automobile airbag structure according to this embodiment, FIG. 2 is an explanatory diagram showing the action, and FIG. 3 is a graph showing the action.

As shown in FIG. 1, inside the lid 2 along the instrument panel section 1 in front of the passenger seat of the automobile,
An airbag unit 3 is arranged. The airbag unit 3 is configured by housing an inflator 5 and an airbag 6 in a reaction can 4, and is set so that the inflation of the airbag 6 is completed immediately after a collision.

The reaction can 4 of the airbag unit 3 is supported by connecting means 7 on both sides of its front end, and supported by an energy storage means 8 at its lower end.

The connecting means 7 includes a bracket 10 extending rearward from the dash panel 9 and a connecting pin 11 connecting the rear end of the bracket 10 to the reaction can 4 of the airbag unit 3. Ori,
The airbag unit 3 is configured to move rearward to follow the movement of the dash panel 9 toward the rear of the vehicle body immediately after a car collision, and to separate the airbag unit 3 from the dash panel 9 side when a set load is exceeded. ing. That is, when the front portion of the vehicle body is crushed during a collision and the dash panel 9 is moved toward the rear of the vehicle body, the bracket 10 moves rearward together with the dash panel 9. The shearing strength of the connecting pin 11 is set so that it will break when the resultant force of the forward movement force of the dash panel 9, the inflation reaction force of the airbag 6, and the reaction force due to the forward movement of the front passenger seat passenger acts on the connection pin 11. ing. And after cutting,
The configuration allows the airbag unit 3 to move toward the front of the vehicle body.

The energy accumulating means 8 is for accumulating the restoring force for returning the air bag unit 3 to the front of the vehicle body when the air bag unit 3 moves toward the rear of the vehicle body during a collision, and has a substantially U-shaped cross section. The structure includes a support plate 12 having a shape. That is, the support plate 12 has a horizontally long upper piece 12a and a lower piece 12b, and the lower piece 12b is attached to a vehicle body side member, such as the steering support member 13, which does not move when the front of the vehicle body is crushed. , a mounting bracket 14 and a mounting tool 15 such as a bolt.
has been fixed through. Further, the upper piece 12a of the support plate 12 is integrally attached to the lower end of the reaction can 4 of the airbag unit 3 via a support bracket 16 and a fixture 17 such as a bolt.

Next, with reference to FIGS. 2 and 3, the operation of this embodiment with the above configuration will be explained in comparison with the conventional example. FIG. 2 shows the behavior of the airbag unit 3 and the front passenger seat occupant 19 at the time of a car collision, with (A) showing the present embodiment and (B) showing the conventional example. Further, the upper row of the diagrams showing both examples shows the state at the time of the collision, the middle row shows the state when the front part of the vehicle body has completely collapsed, and the lower row shows the forward movement state of the occupant after that. Note that, as a conventional example, a configuration in which the airbag unit 3 is simply supported by the steering support member 13 is shown.

At the time of a collision, as shown in the upper rows of FIGS. 2A and 2B, in both this embodiment and the conventional example, the front passenger seat occupant 19 is separated from the dash panel 9 by a certain distance.

Next, when the dash panel 9 moves backward a distance B due to the crushing of the front part of the vehicle body at the time of the collision, by this time the airbag 6 has already been inflated and deployed, and the occupant restraint force is exerted. However, in the conventional example, Fig. 2 (B
) As shown in the middle row, the airbag unit 3 is at the initial position, and the front passenger seat occupant 19 moves forward by a distance A1. In contrast, in this embodiment, the airbag unit 3
is pushed by the bracket 10 and moves backward by a distance B together with the dash panel 9. At this point, when comparing the two with the same restraining force of the airbag 6, the front passenger seat passenger 1
9 moves forward of the vehicle by a distance A that is smaller than the distance A1. At this time, the support plate 9 of the energy storage means 8 extends rearward and stores energy for the forward return of the airbag unit 3.

Finally, as shown in the lower rows of FIGS. 2(A) and 2(B), the front passenger seat occupant 19 moves further forward, but in this case, in the conventional example, the position of the airbag unit 3 remains unchanged. Then, the front passenger seat occupant 19 moves forward by a distance C1. On the other hand, in this embodiment, the connecting pin 11 is disconnected and the energy accumulating means 8 acts accordingly, so that the airbag unit 3 is moved forward by a distance D, and the front passenger seat 19 is moved by a distance C. Moving. In this state, regarding the occupant restraint force by the airbag 6, in the conventional example, the airbag unit 3 does not move, so the occupant 19 has only a distance C1 to move.
On the other hand, in this embodiment, the forward movement of the airbag unit 3 has a margin corresponding to a distance (C+D) larger than the distance C1. Therefore, as shown in FIG. 3, in the conventional example (see broken line a in the figure), the occupant restraint force becomes considerably high, whereas in this embodiment (see practice b in the figure),
The restraint force for the occupant can be lowered, and the restraint force can be relaxed. Furthermore, as is clear from this graph, the occupant 19 and the airbag unit 3 approach each other immediately after the collision, so the occupant 19 can be restrained by the airbag 6 at an early stage.

The inflation speed of the airbag unit 3 is set by the gas pressure generated by the propellant of the inflator 5, but if all the propellants are applied at once, the rise will be sudden as shown by the solid line c in FIG. , the initial restraint force increases rapidly accordingly, so in this example, after once applying a part of the propellant, the remaining propellant is applied after a certain time delay, as shown by the broken line d in Fig. 4. The rise speed itself at the initial stage of expansion can also be relaxed. This makes the above-mentioned restraint force relaxation even more effective.

[0023]

As described above, according to the present invention, the restraint force relieving means moves the airbag unit rearward to follow the movement of the front part of the vehicle body toward the rear of the vehicle body, and then moves the airbag toward the front of the vehicle body. This allows the airbag unit to approach the occupant and exert sufficient restraint force from immediately after the collision until the front of the vehicle is completely collapsed, and after that, the airbag unit, once close to the occupant, can move in the opposite direction. It is possible to move away from the occupant in order to alleviate the occupant restraining force caused by the airbag, which would be excessive if the airbag remained close to the occupant, and to preferably set the restraining force of the airbag on the occupant over time. can. Therefore, it can be preferably applied to a vehicle such as a commercial vehicle that has almost no crash space such as an engine room in the front part of the vehicle body in front of the passenger seat, and can provide an appropriate restraint force to the passenger seat occupant.

[Brief explanation of drawings]

FIG. 1 is a side view showing one embodiment of the present invention.

FIG. 2 (A) is a diagram showing the operation of the embodiment. (B) It is a figure showing the effect of a conventional example.

FIG. 3 is a graph showing the effects of the embodiment in comparison with the effects of a conventional example.

FIG. 4 is a graph showing the expansion characteristics of the airbag unit.

[Explanation of symbols]

3 Airbag unit 6 Airbag 7. Connection means 8 Energy storage means 9 Dash panel 10 Bracket 11 Connecting pin 12 Support plate

Claims (4)

[Claims] Claim 1: An airbag unit installed in front of the passenger seat that inflates and deploys the airbag is moved rearward to follow the movement of the front part of the vehicle to the rear of the vehicle, and then the airbag unit is moved to the front of the vehicle. Let me return to
An airbag structure for an automobile, characterized in that a restraint force relaxation means is provided to relieve the restraint force caused by the airbag. 2. The restraint force relieving means is provided between the front part of the vehicle body and the airbag unit to connect them, and is configured to reduce the air pressure by following the movement of the front part of the vehicle body toward the rear of the vehicle body. Claim 1 characterized in that it has a connecting means that moves the bag unit rearward and separates the front part of the vehicle body and the air bag unit when a load exceeds a set load.
Automotive airbag structure described. 3. A claim characterized in that the restraining force alleviating means includes energy storage means for accumulating a restoring force for returning the airbag unit to the front of the vehicle body when the airbag unit moves toward the rear of the vehicle body. The automobile airbag structure according to any one of Items 1 and 2. 4. The energy storage means has a U-shaped cross section, one end of which is attached to a vehicle body side member insulated from the front of the vehicle that is moved toward the rear of the vehicle, and the other end of which is connected to the airbag unit. 4. The airbag structure for an automobile according to claim 3, wherein the airbag structure is comprised of a support plate.