JPH10217903A - Impact absorbing body for car body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain sufficient impact absorption effects even if a small object collides against a car over a wide area by plastically deforming at least a surface layer side of a double structural body into a swelling shape when fluid pressure is filled therein. SOLUTION: When an automobile which is running collides against a pedestrian, a pedestrian collision detection switch 7 is closed, an ignition current flows in an inflator 5, and the resultant gas blows into the inside of an engine hood 1 having a double structure through an opening 4. Then, the whole surface of a surface layer material 2 of the engine hood 1 swells upward due to the pressure as shown by a two-dot chain line and is plastically deformed into the swelling shape. Consequently, a space 8 generated between the surface layer material 2 and a rear layer material 3 becomes an impact absorption stroke. When the head of the pedestrian who falls down because his leg is swept out from under him by a front bumper 6 collides against the engine hood 1, the surface layer material 2 catches the pedestrian's head and caves in.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention alleviates the impact of a pedestrian or a light vehicle by creating a stroke for reducing the deceleration when the pedestrian or the light vehicle collides with the body of an automobile. The present invention relates to a vehicle body shock absorber for absorbing a shock when a vehicle spins or rotates after a collision and hits a road structure.

[0002]

2. Description of the Related Art In a car-to-pedestrian collision, only a slight damage is required if the vehicle hits a bumper. However, a pedestrian who has been lifted by the bumper falls down on the engine hood, and falls on the upper surface of the engine hood. There are cases where the injury is increased because the head is hit. In this case, the rigidity of the engine hood is high and it is difficult to deform, so the damage to the pedestrian will be large.As long as it can take some stroke to reduce the deceleration at the time of collision, the damage to the pedestrian will be It can be significantly reduced. As a technique based on such a viewpoint, for example, Japanese Patent Application Laid-Open No. 7-108902 proposes an airbag device configured to be inflated on an upper surface of an engine hood.

[0003]

However, in this technology, since the airbag must be deployed on the entire surface of the engine hood, the airbag has a much larger capacity than an occupant airbag that is already in practical use. An airbag is required. Therefore, the size of the inflator for inflating the inflator at a high speed is also increased, so that the storage space for the inflator becomes a problem. Further, piercing a part of the engine hood so that the airbag can be inflated requires a significant change in the structure of the conventional vehicle body, and inevitably has a considerable effect on the appearance of the vehicle body. Moreover, since the volume of the airbag is large, if the area of the collision object is small, the internal pressure of the airbag does not increase and the sufficient impact absorbing effect cannot be obtained with a simple bag-shaped airbag. In order to solve this, measures such as partitioning the inside of the airbag into a plurality of small rooms and pulling the surface side of the airbag with a string from the inside to prevent the gas pressure from dispersing inside the airbag. However, when the internal structure is complicated in this way, it is extremely difficult to uniformly fold at high speed after folding compactly.

[0004] The present invention has been devised to solve the problems of the prior art as described above.
In addition to having to change the conventional body structure significantly,
An object of the present invention is to provide a shock absorber for a vehicle body improved so that a sufficient shock absorbing effect can be obtained even when a small object collides with a large area.

[0005]

In order to achieve the above object, according to the present invention, at least a part of an outer shell of a vehicle body is formed by a double structure having a substantially closed periphery. At least the surface layer side of the double structure was plastically deformed into a swollen shape when a fluid pressure was injected. In particular, the double-layered structure may be configured such that the surface layer is formed of an extensible material capable of being plastically deformed by fluid pressure, and the back layer side is formed of a rigid material capable of retaining the shape of the vehicle body outer shell. ,
It is preferable that the inflator operated by a signal from a collision detection sensor for a pedestrian or the like expands by a gas pressure generated. According to this, when a collision with a pedestrian is sensed, the surface layer of the engine hood instantaneously swells due to gas pressure or the like and swells to create a shock-absorbing stroke. It is absorbed by plastic deformation resistance.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below in detail with reference to specific embodiments shown in the accompanying drawings.

FIG. 1 shows an automobile in which an impact absorber according to the present invention is applied to an engine hood. The engine hood 1 has a double structure in which a surface layer material 2 which is rich in extensibility and is relatively easily plastically deformed and a back layer material 3 having relatively high rigidity are overlapped and the periphery thereof is substantially sealed. Yes,
It is shaped like a flat bag.

An opening 4 is provided at the rear end of the engine hood 1. An opening 4 is filled with an inflator 5 filled with a substance that generates a gas at an appropriate pressure by a chemical reaction such as combustion. They are arranged adjacently.

The front bumper 6 is provided with a pedestrian collision detection switch 7 using, for example, a pressure-sensitive element or a touch sensor.

Next, the operation of the present invention will be described. When the running car hits a pedestrian, the pedestrian collision detection switch 7 closes and an ignition current flows through the inflator 5, and the resulting gas is blown from the opening 4 into the engine hood 1 having a double structure. . Then, the entire surface of the surface material 2 of the engine hood 1 swells upward by the pressure as shown by a two-dot chain line in FIG. 1 and is plastically deformed to the swelling shape.

As a result, the space 8 created between the surface layer material 2 and the back layer material 3 becomes a shock absorbing stroke, and the head of the pedestrian P who has fallen by the foot on the front bumper 6 is moved by the engine hood 1. When the collision occurs, the surface material 2 receives the head of the pedestrian P and falls. The buffer action is obtained by the residual gas pressure in the space 8 at that time, and the surface material 2
The collision energy is absorbed by the deformation resistance (see FIG. 2).

The shock absorber of the present invention is applicable not only to the above-described engine hood 1 but also to all parts of the vehicle body such as the front bumper 6, the roof 9, the pillar 10, and the door 11, as shown in FIG. is there. In addition, it is effective not only to reduce the impact of collision with pedestrians and light vehicles, but also to protect occupants from secondary impact when the vehicle collides and is bounced off and collides with a building on the road. is there. In the case of a bumper, the structure is not limited to the bumper itself, and the above structure may be incorporated in a bumper beam supporting the bumper so that the entire bumper protrudes forward.

[0013]

As described above, according to the present invention, since the collision energy is absorbed by the plastic deformation resistance of the structure constituting the outer shell of the vehicle body, it is possible to cope with a local collision and, for example, to use a polymer material. There is no need for space to fold and store the airbag made of the fabric, and it is not necessary to make the appearance of the car body special, so it has less impact on manufacturing costs and body design. It has a great effect on increasing the degree of freedom. In addition, quality control is easy because individual differences can be easily reduced as compared with the conventional method in which deceleration is controlled solely by gas pressure.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view of an automobile to which the present invention is applied.

FIG. 2 is a side view of the main part of the vehicle for explaining the operation of the present invention.

FIG. 3 is an overall perspective view of an automobile showing an example of an application portion of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine hood 2 Surface layer material 3 Back layer material 4 Opening 5 Inflator 6 Front bumper 7 Pedestrian collision detection switch 8 Space 9 Roof 10 Pillar 11 Door

Claims (3)

[Claims] At least a portion of an outer shell of a vehicle body is formed of a double structure having a substantially closed periphery, and at least a surface side of the double structure is injected with a fluid pressure therein. An impact absorber for a vehicle body characterized by being plastically deformed into a swelling shape. 2. The double-structure body is formed on the surface layer side with an extensible material capable of being plastically deformed by fluid pressure, and on the back layer side with a rigid material capable of maintaining the shape of the vehicle body shell. The shock absorber for a vehicle body according to claim 1, wherein the shock absorber is a body. 3. The shock absorber for a vehicle body according to claim 1, wherein an inflator operated by a signal from a collision detection sensor for a pedestrian or the like expands by a gas pressure generated.