JP2001225764A - Body structure for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the degree of freedom in designing a vehicle body and the optimization of body rigidity in a body structure capable of reducing the occupant deceleration at a collision. SOLUTION: A sub-frame 5 from the front section of a body floor part 4 to a body front end section is connected to a connecting member 6 to form a collision load transmission member, and a seat is connected to the body rear end section of the connecting member. A holder 11 serving as a slide support section is fixed to the lower face of a floor side frame member 10 provided between the floor part 4 and a side frame 8, and a bulge member 12 capable of colliding with the holder 11 is fixed to the collision load transmission member. Since the slide support section is provided on the body front side of a body floor, the collision load transmission member can be made short in length and lightweight, and the slide support section can be provided at the place where the rigidity of an engine room or the like can be easily secured, thereby the limitation on the design of a cabin side is reduced, and the degree of freedom in designing the vehicle body and the optimization of body rigidity can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body structure for improving the collision safety of a vehicle.

[0002]

2. Description of the Related Art In recent years, in order to enhance the occupant protection effect at the time of a collision of an automobile, the deformation mode of a portion other than the living space of the vehicle body at the time of the collision is appropriately set to reduce the deceleration of the living space portion of the vehicle body. At the same time, various vehicle body structures have been proposed in which the deformation does not reach the living space.
No. 101354).

[0003] In the event of an automobile collision, the restraint device such as a seat belt acting as a spring causes a time delay in the occupant deceleration with respect to the vehicle deceleration. When the maximum is reached, the occupant deceleration becomes maximum. Therefore, in order to reduce the occupant deceleration (occupant injury value) at the time of a collision, it is preferable to reduce not only the average deceleration of the vehicle body but also the overshoot of the occupant due to the spring action of the restraint device.

The waveform of the vehicle deceleration is an important factor in reducing the occupant injury value. As shown in FIG. 8, the waveform of the vehicle body deceleration G2 that can suppress the occupant deceleration G1 that meets the above-mentioned purpose is small as shown by the solid line in FIG. After a larger deceleration is generated for a fixed time (short time), a reverse deceleration is generated for a short time (section b in the figure), and then the vehicle is decelerated with an average deceleration (section c in the figure). Possible waveform. With the waveform of the deceleration G2 of the vehicle body, the overshoot of the occupant can be reduced by the deceleration in the opposite direction in the section b, and the distance required for decelerating the vehicle body (dynamic stroke) is the same constant deceleration. The simulation performed by the inventors of the present application has confirmed that the occupant deceleration G1 can be further reduced as compared with the case of (square wave).

[0005]

The vehicle body deceleration G2 is a seat deceleration. In order to make the occupant deceleration G1 substantially equal to the vehicle body deceleration G2 in the section c, the occupant must be restrained to the seat by a seat belt. A belt-integrated seat structure in which both ends of the seat belt are connected to the seat is conceivable. In order to realize the above-mentioned waveform in such a belt-integrated sheet structure, for example, as shown in FIG.
The collision load transmitting member 21 extends in the vehicle longitudinal direction separately from the vehicle body floor 22, and the seat 23 is integrally connected to the collision load transmitting member 21.
It is conceivable to provide a stopper 24 integrally formed on the vehicle body floor 22 behind the rear end of the vehicle body 1 at a predetermined distance from the vehicle body rear end of the collision load transmitting member 21.

According to this structure, as shown in FIG. 9B, when the front portion of the vehicle body is compressed and deformed at the time of a frontal collision, the collision load transmitting member 21 applies a seat 23 to the vehicle body floor 22 which is displaced forward. Is relatively displaced rearward, and the rear end of the vehicle body of the collision load transmitting member 21 collides with the stopper 24 to generate a reverse deceleration. Thereafter, in conjunction with the buckling deformation of the collision load transmitting member 21, The above deceleration waveform can be realized by absorbing the impact load.

However, since the collision load transmitting member 21 strikes the stopper 24 integrated with the vehicle body floor 22 to generate the above-described reverse deceleration, it is necessary to increase the rigidity of the portion receiving the collision load. In the case where the stopper 24 is formed by the cross member of the vehicle body floor 22 as in the illustrated example, it is necessary to increase the rigidity of the cross member or to separately provide a high rigidity stopper below the vehicle body floor 22. There are problems in that the degree of freedom in design is reduced and the rigidity of the vehicle body is difficult to balance.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, it is possible to improve the degree of freedom in vehicle design and the optimization of vehicle rigidity in a vehicle structure capable of reducing the occupant deceleration in a collision. In the present invention, the occupant restraint system (1)
The collision load transmitting member (5, 6) coupled to (3) is provided so as to extend in the front-rear direction of the vehicle body, and at the time of a collision, the collision load transmitting member (5.6) is crushed and buckled. And a stopper (24) for the stopper (2).
4) a sliding support portion (11.13) provided on the vehicle body floor (4) for slidably supporting the collision load transmitting member (5.6) on the vehicle body floor (4). When,
An abutting portion (12, 14) provided on the collision load transmitting member (5, 6) to abut the sliding support portion, wherein the sliding support portion (11, 13) is provided on the vehicle body. It is provided on the floor (4) on the front side of the vehicle body.

According to this structure, for example, a seat belt-integrated seat as an occupant restraint device is connected to the collision load transmitting member, so that the seat is relatively displaced rearward of the vehicle body in the event of a collision, thereby moving the seat forward. By preventing the movement of the occupant, the deceleration of the occupant can be started up quickly, and then the abutting portion provided on the collision load transmitting member abuts on the sliding support portion provided on the vehicle body floor, The displacement of the collision load transmitting member toward the rear of the vehicle stops, and at that time, a deceleration in the opposite direction can be generated in the seat, and the buckling deformation of the subsequent collision load transmitting member absorbs the impact force, and at the end of the collision A desirable vehicle deceleration waveform that makes the deceleration of the occupant substantially equal to the deceleration of the vehicle body (seat) can be realized. By providing the sliding support portion on the front side of the vehicle body on the vehicle body floor,
For example, it is not necessary to extend the rear end of the collision load transmitting member to the rear of the vehicle body from the seat and to provide a stopper behind the seat,
The length of the collision load transmitting member can be minimized, and a sliding support portion can be provided at a position where rigidity is easily ensured, for example, in an engine room of a front engine vehicle. Can be reduced, and the degree of freedom in designing the vehicle body and the optimization of the rigidity of the vehicle body can be improved.

[0010] Further, at least one of the sliding support portion (11, 13) and the abutment portion (12, 14) is provided with a compressive load absorbing deformation portion (11a, 14b). For example, it is possible to adjust the reverse deceleration waveform generated in the occupant restraint system by stopping the displacement of the collision load transmitting member to the rear of the vehicle body, for example, to prevent a steep change and gradually change the waveform. .

[0011]

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

FIG. 1 is a schematic side view showing an outline of a vehicle body structure of a vehicle to which the present invention is applied. In this vehicle body structure, a seatbelt-integrated seat in which a seatbelt 3 is integrally connected to the seat 1 is used as an occupant restraint device that restrains the movement of the occupant 2 with respect to the seat 1.

In this vehicle, an engine is mounted on a front part of a vehicle body. In an engine room at a front part of the vehicle body, a subframe 5 extending from a lower part on a vehicle body front side of a floor member 4 constituting a vehicle body floor to a front end part of the vehicle body is provided. Is provided. The sub-frames 5 are provided in a pair on the left and right sides in the vehicle width direction.
It may be used to support an engine or suspension (not shown). Also, subframe 5
A connection member 6 extending below the seat 1 is integrally connected to an end of the vehicle compartment side, and the sub-frame 5 and the connection member 6 form a collision load transmitting member in a single rod shape.

Further, for example, a base 18 is fixed to a bracket 6a formed so as to penetrate the floor member 4 from the connecting member 6 and protrude toward the passenger compartment (upper surface of the floor member). The seat 1 is provided so as to be position-adjustable via a seat rail fixed to the vehicle.
The opening provided in the floor member 4 for penetrating the bracket 6a has a length such that the bracket 6a can be displaced by an arbitrary distance with respect to the floor member 4 in the vehicle longitudinal direction.

At the boundary between the engine room and the cabin, a front dashboard 7 is provided so as to rise from the front end of the vehicle body of the floor member 4. In the engine room, there is provided a front side frame 8 connected to the front dashboard 7 and extending to the front end of the vehicle body. The vehicle body structure may be formed as shown in FIG. 2. As also shown in FIG. 2, the front end portion of the front side frame 8 and the sub-frame 5 means the members 9a and 9b extending in the vehicle width direction.
And a front member 9 comprising a bracket 9c provided at the center of the member 9b.

In the present vehicle body structure, the lower surface of the vehicle body at the corner formed by the floor member 4 and the front dashboard 7 and the intermediate portion of the collision load transmitting member (the subframe 5 and the connecting member 6). Is provided with a stopper according to the invention. In the example of FIG.
On the lower surface of the floor-side frame member 10 provided between the floor member 4 and the front side frame 8, a holder 11 formed by pressing a thin plate into a concave shape as shown in FIG. It is adapted to be fixed by bolts 16.

Note that a rear half portion of the holder 11 is fixed by bolts 16 and, as shown in FIG. 3, a compression load absorbing deformation portion 11a which is deformed by a compression load is provided on the front half portion of the holder 11 as shown in FIG. Is provided. A block-shaped bulge member 12 as an abutting portion is fixed to the sub-frame 5 by, for example, welding so as to face the holder 11 at a predetermined distance from the front side of the vehicle body.

The sub-frame 5 has a cross beam 5c for connecting members extending in the front-rear direction of the left and right vehicle bodies.
Are provided integrally, and brackets 5a and 5b each having a corresponding shape are integrally provided at an appropriate position in order to supportably mount an engine, a suspension, and the like (not shown). In this structure, the subframe 5 used to support the engine, the suspension and the like is used as a shock absorbing member at the time of a collision.

Next, the operation of the present invention will be described with reference to FIG. 4 and FIG. 8 showing a conventional example, assuming a case where a vehicle collides head-on with a road structure.

At the moment when the vehicle collides, the front side frame 8 and both front end portions of the collision load transmitting member 5 both receive an impact load and start deforming. Since the mass is sufficiently small, the deformation of the front end of the subframe 5 is small,
The rear side (connection member 6) of the sub-frame 5 is displaced relatively rearward of the vehicle body with respect to the front side frame 8. Therefore, the seat 1 coupled to the connecting member 6 via the base 18 with a large deceleration (section a in FIG. 8) that rises more steeply than the front side frame 8 side.
Slows down earlier. Therefore, the seat 1 moves rearward relative to the floor member 4 that continues to move forward due to the compression deformation of the front side frame 8.

In this state, the occupant 2 tends to move forward due to inertial force. However, due to the seat belt integrated type seat structure, the restraining force of the seat belt 3 applied to the occupant 2 increases, and the occupant 2 moves forward. Is prevented from moving.

In the middle stage of the collision, the bulge member 12 fixed to the sub-frame 5 which has a large deceleration due to its front portion being struck, comes into contact with the holder 11. Then, the inertia force on the floor member 4 side is transmitted to the bulge member 12, and the impact load causes the compressive load absorbing deformation portion 11a of the holder 11 to buckle, and the floor member 4 and the connecting member remain until there is no room for the buckling deformation. 6 (sheet 1) continues to move. The bulge member 12 and the holder 1
1, a force opposing a collision load acting on the front side frame 8 is applied to the seat 1 via the connecting member 6, and acts on the occupant 2 by acceleration in the vehicle traveling direction at the time of the collision. The inertia force acting forward is canceled (the first half of the section b in FIG. 8).

In the latter half of the middle stage of the collision, the deceleration increases at the moment when the deformation stress of the sub-frame 5 is added to the deformation stress of the front side frame 8 (the latter half of the section b in FIG. 8). Decelerates in unison, the relative speed between the floor member 4 and the seat 1 becomes zero through the above process, and the restraint load of the seat belt 3 balances with the deceleration at the end of the collision. 4
Then, the vehicle decelerates integrally with the seat 1, and this state continues until the vehicle body completely stops (section c in FIG. 8).

According to this structure, the sliding support portion (holder 1)
1) Since the compressive load absorbing and deforming portion 11a is provided at a place (floor side frame member 10) where rigidity can be easily secured, such as an engine room (a front engine vehicle), restrictions on the design of the vehicle interior are reduced, and And the optimization of the vehicle body rigidity can be improved. Further, as compared with the conventional structure in which the collision portion is provided on the rear side of the vehicle body and the rigidity of the collision portion is increased, the size and weight of the stopper can be improved.

According to the present invention, the compressive load absorbing deformation portion 11
The member for providing a (the holder 11 in the illustrated example) is not specified, and the configuration may be reverse to that of the illustrated example. One example is shown below with reference to FIG.

FIG. 5 corresponds to FIG. 3, and in the second example shown in FIG.
Is fixed to the floor side frame member 10 with bolts 17, and a buckling member 14 serving as an abutment portion acting as the holder 11 is fixed to the collision load transmitting member 15. The collision load transmitting member 15 may be a sub-frame as in the above-described example, or may be a member provided to extend in the vehicle longitudinal direction separately from the front side frame 8.

As shown in FIG. 5, the holder 13 has a block shape, and has a through-hole 13a at the center thereof in the thickness direction (in the longitudinal direction of the vehicle body in the mounted state). The collision load transmitting member 15 in the illustrated example is formed in, for example, a pipe shape that can be loosely inserted into the through hole 13a.
Note that the collision load transmitting member 15 is
Is preferably supported by the holder 13 with a frictional engagement force capable of sliding with a load smaller than the load that buckles and deforms at the time of collision in the axial direction. As shown in the figure, the buckling member 14 is opposed to the rigid body 14a on the boss side fixed to the outer peripheral surface of the collision load transmitting member 15 in a penetrating state, and faces the holder 13 integrally with the rigid body 14a. And a cylindrical compressive load absorbing and deforming portion 14b formed coaxially.

In the second example, at the time of a collision, the compressive load absorbing deformation portion 14b of the buckling member 14 deforms in a bellows shape as shown in FIG. The operation and effect in the second example are the same as those in the above-described example, and the same deceleration waveform at the time of collision as described above can be obtained. In each of these examples, the compressive load absorbing and deforming portions 11a and 14b are provided on one of the sliding support portion and the abutting portion, but they may be provided on both. In that case, even if the distance between the initial installation of the two is short, a large amount of displacement of the collision load transmitting member can be ensured, which is suitable for a vehicle with limited space.

FIG. 7 shows a third example according to the present invention. FIG. 7 corresponds to FIG. 5 described above, and the same parts as those in the illustrated example are denoted by the same reference numerals, and detailed description thereof will be omitted. In this third example, an annular block 19 as an abutment portion is fixed to the collision load transmitting member 15 and the annular block 19 is moved by a relative displacement between the floor member 4 and the collision load transmitting member 15 at the time of collision. And the holder 13 collide.

As a result of the collision, a force opposing the collision load acting on the front side frame 8 is applied to the seat 1 via the connecting member 6 in the same manner as in the illustrated example, and the vehicle travels in the collision direction. The inertia force acting on the occupant 2 in the forward direction is canceled by the acceleration toward (the first half of the section b in FIG. 8). As described above, a similar deceleration waveform can be realized. In the third example, the deceleration waveform cannot be adjusted by the compressive load absorbing and deforming portion, but the effect of providing the position of the stopper at the front portion of the vehicle body is the same as that in the above-described example.

[0031]

As described above, according to the present invention, for example, a seat belt integrated type seat as an occupant restraint device is connected to the collision load transmitting member, so that the seat is relatively displaced rearward of the vehicle body in the event of a collision. As a result, the forward movement of the occupant can be prevented, and the deceleration of the occupant can be started up at an early stage. Then, the abutting portion provided on the collision load transmitting member is connected to the sliding support portion provided on the vehicle body floor. By striking,
The displacement of the collision load transmitting member toward the rear of the vehicle stops, and at that time, a deceleration in the opposite direction can be generated in the seat, and the buckling deformation of the subsequent collision load transmitting member absorbs the impact force, and at the end of the collision A desirable vehicle deceleration waveform that makes the deceleration of the occupant substantially equal to the deceleration of the vehicle body (seat) can be realized.
By providing the sliding support portion on the front side of the vehicle body on the vehicle body floor, for example, the rear end of the collision load transmitting member is extended rearward of the vehicle body from the seat and a stopper is provided behind the collision load transmitting member. The length of the transmission member can be shortened and reduced in weight, and a sliding support portion can be provided at a position where rigidity can be easily ensured, for example, in an engine room of a front engine vehicle. Therefore, the degree of freedom in designing the vehicle body and the optimization of the rigidity of the vehicle body can be improved.

Further, by providing a compressive load absorbing and deforming portion on at least one of the sliding support portion and the abutting portion, the displacement of the collision load transmitting member to the rear of the vehicle body is stopped and generated by the occupant restraint device. The deceleration waveform in the opposite direction can be adjusted so as to prevent abrupt change and change gently, for example, and such a compressive load absorbing and deforming part is also located at the front part of the vehicle body. The degree of freedom in designing is improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view schematically showing a vehicle body structure of a vehicle to which the present invention is applied.

FIG. 2 is an exploded perspective view showing a main part of a vehicle body structure to which the present invention is applied.

FIG. 3 is an exploded perspective view of a main part according to the present invention.

FIG. 4 is a view corresponding to FIG. 1, showing a frontal collision state of a vehicle to which the present invention is applied.

FIG. 5 is an exploded perspective view of a main part showing a second example.

FIG. 6 is an essential part side view showing a deformed state at the time of a collision in the second example.

FIG. 7 is an exploded perspective view of a main part showing a third example.

FIG. 8 is a desirable waveform diagram of vehicle body deceleration and occupant deceleration.

9A is a schematic side view schematically showing a vehicle body structure for realizing the deceleration waveform shown in FIG. 8, and FIG. 9B is a diagram showing a front collision state of the vehicle.

[Explanation of symbols]

 Reference Signs List 1 seat (occupant restraint device) 3 seat belt (occupant restraint device) 4 floor member (vehicle body floor) 5 collision load transmitting member 6 connecting member (collision load transmitting member) 11 holder (sliding support portion) 11a compression load absorbing deformation portion Reference Signs List 12 bulge member (collision part) 13 Holder (sliding support part) 14 Buckling member (collision part) 14a Compressive load absorbing deformation part 19 Ring block (collision part)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takahiro Kamei 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 3D003 AA05 BB01 CA09 CA18 DA19

Claims (2)

[Claims] 1. A collision load transmitting member coupled to an occupant restraint device is provided so as to extend in the vehicle longitudinal direction, and a stopper is provided for abutting the collision load transmitting member to cause buckling deformation in a collision. A stopper provided on the vehicle body floor for slidably supporting the collision load transmitting member on the vehicle body floor; and the collision load for abutting against the slide support portion. A vehicle body structure for an automobile, comprising an abutment portion provided on a transmission member, wherein the sliding support portion is provided on a vehicle body front side of the vehicle body floor. 2. The vehicle body structure according to claim 1, wherein a compression load absorbing deformation portion is provided on at least one of the sliding support portion and the abutment portion.