JP3653932B2 - Body structure of vehicle with frame - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle body structure that restricts an excessive movement of a vehicle having a vehicle body mounted on a frame by restricting the forward movement of the vehicle body in the event of a frontal collision of the vehicle.
[0002]
[Prior art]
In a vehicle having a frame, the vehicle body is elastically supported with respect to the frame via a rubber or the like, and has a structure that restricts the vehicle body from moving excessively forward with respect to the frame by a stopper. For example, Japanese Patent Laid-Open No. 5-185952 discloses a vehicle body structure of this type.
[0003]
In such a vehicle body structure, by quickly transmitting the impact force applied to the frame at the time of a frontal collision of the vehicle to the vehicle body side through the stopper,
(A) To quickly achieve the initial restraint of the occupant by the seat belt.
(B) Quickly actuate the sensor of the airbag installed in the vehicle body.
(C) By restricting the vehicle body from moving excessively forward, the vehicle body mounting mechanism is prevented from being damaged, and a living space for the occupant is secured.
Such actions and effects are expected.
[0004]
[Problems to be solved by the invention]
However, in this type of vehicle structure, if the stopper is too rigid, the impact force of the frame is transmitted directly to the vehicle, causing the vehicle to decelerate rapidly and the occupant to move greatly forward. End up. On the other hand, if the stopper is insufficiently rigid, the stopper will be greatly deformed, and the vehicle body will get over the deformed stopper, so that the mount part will eventually be damaged or the forward movement of the vehicle body cannot be restricted. This causes a malfunction.
Therefore, the present invention provides a vehicle body structure that eliminates the above-described problems.
[0005]
[Means for Solving the Problems]
The vehicle body structure of the present invention is provided at a side member extending in the front-rear direction on both sides of the vehicle, a vehicle body elastically supported on the side member, a stopper device provided on the side member, and a vehicle body portion facing the stopper device. And a protrusion. The stopper device includes a first stopper member facing the protruding portion with a gap, and a second stopper member disposed on the opposite side of the protruding portion with respect to the first stopper member. Is provided.
The stopper device includes a first stopper member including a wall portion facing the protruding portion and a support portion orthogonal to the wall portion, and a tapered portion facing the back surface of the wall portion of the first stopper member. The second stopper member is provided.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an explanatory diagram showing the structure of a vehicle to which the present invention is applied.
The vehicle denoted by reference numeral 1 as a whole has a structure in which a vehicle body 10 is mounted on an upper portion of a frame 20.
The frame 20 includes a side member 22 disposed on both sides of the vehicle in parallel to the axial direction of the vehicle, and a plurality of cross members 30 disposed between the side members 22. It is called a ladder frame.
[0007]
FIG. 2 shows the vehicle body structure at the rear of the vehicle, and a protrusion (bolster) provided on the lower surface of the vehicle body 10 facing the stopper structure 40 mounted on the support bracket 24 fixed to the rear end outside of the side member 22. 12 is shown.
[0008]
FIG. 3 is a perspective view showing a mounting position of the stopper device 40 with respect to the frame.
The stopper device 40 includes a first stopper member 50 and a second stopper member 60.
The first stopper member 50 has a planar shape composed of a wall portion 52 bent substantially at a right angle and a wall portion 54 serving as a support portion, and one wall portion 52 faces the protruding portion of the vehicle body. The side member 22 and the bracket 24 are welded in a posture. The second stopper member 60 has an inclined portion 62, and the inclined portion 62 is welded onto the bracket 24 in a posture close to the back surface of the wall portion 52 of the first stopper member 50.
[0009]
FIG. 4 is a side view showing a positional relationship between the protruding portion 12 of the vehicle body 10 and the stopper device 40 on the frame side in a normal state.
The first stopper member 50 of the stopper device 40 is disposed at a position where the wall portion 52 has a gap G with respect to the protruding portion 12 of the vehicle body. The vehicle body 10 is mounted on the frame 20 via an elastic member such as a rubber member. Accordingly, the vehicle body 10 moves within a certain distance in the horizontal direction with respect to the frame 20 even in a normal traveling state.
The gap G is set to a size larger than the relative movement between the normal vehicle body and the frame.
[0010]
When the vehicle undergoes a frontal collision, a large negative acceleration acts on the side member 22 constituting the frame in response to the impact force. The vehicle body 10 supported on the frame via the elastic member moves forward by the action of the inertial force F ₁ , and the projecting portion 12 is brought into contact with the first stopper member 50 of the stopper device 40 as shown in FIG. collide.
Due to this collision, a negative acceleration is also generated in the vehicle body 10 to activate the restraint device for the seat belt and to activate the sensor for the airbag.
[0011]
The first stopper member 50 undergoes plastic deformation due to the inertial force of the vehicle body and is crushed. The first stopper member 50 absorbs impact energy while causing plastic deformation.
As the deformation of the first stopper 50 progresses, the back surface of the wall portion 52 of the first stopper member 50 finally comes into contact with the tapered portion 62 of the second stopper member 60 as shown in FIG.
[0012]
Since the second stopper member 60 has a large rigidity in the front-rear direction of the vehicle, the movement of the vehicle body 10 forward is completely restricted by the second stopper member 60. This action prevents the vehicle body from moving beyond the allowable range of the support device with respect to the frame, and ensures the safety of the passenger.
[0013]
In FIG. 7, the horizontal axis represents the relative movement amount between the vehicle body and the frame, and the vertical axis represents the drag by the stopper.
The curve C ₁ of the vehicle body structure having one conventional stopper member is indicated by a two-dot chain line, and the curve C ₂ of the vehicle body structure of the present invention is indicated by a solid line.
[0014]
In the vehicle body structure of the present invention, by setting the rigidity of the first stopper member 50 of the stopper device 40 to be relatively small, the rising of the drag can be set gently as shown by the region S _1. . Thereby, the negative acceleration which acts on a passenger | crew can be suppressed small. Further, the peak P ₂ can also be made lower than the conventional curve P _1, and the impact force applied to the vehicle body can be reduced.
When plastic deformation of the first stopper member progresses, the curve of the drag draws a curve right downward as indicated by the region S _2.
[0015]
A point P ₃ indicates a position where the first stopper member 50 is in contact with the second stopper member 60, and the drag curve region S ₃ rises rapidly from this point P ₃ and exceeds the allowable relative movement amount δ ₁ . It is prevented.
[0016]
【The invention's effect】
As described above, the vehicle body structure of the present invention comprises a vehicle body stopper device mounted on a frame, which is composed of two members. In order to restrict the vehicle body that moves forward by inertia force against the frame that stops at a large negative acceleration at the time of a frontal collision of the vehicle, the stopper device provided on the frame is stopped by a two-stage stopper member. The rise of acceleration can be mitigated. Accordingly, the impact applied to the occupant is reduced. In addition, since the amount of movement of the vehicle body remains within the durability range of the mounting device for the vehicle body, it is possible to secure a living space for the occupant.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an outline of a vehicle implementing the present invention.
FIG. 2 is a side view showing a main part of a vehicle for carrying out the present invention.
FIG. 3 is a perspective view of a stopper device.
FIG. 4 is an explanatory diagram showing the operation of the present invention.
FIG. 5 is an explanatory diagram showing the operation of the present invention.
FIG. 6 is an explanatory diagram showing the operation of the present invention.
FIG. 7 is an explanatory diagram showing a relationship between a relative movement amount of a vehicle body and a drag force according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vehicle 10 Car body 12 Protruding part 20 Frame 22 Side member 24 Support bracket 30 Cross member 40 Stopper device 50 First stopper member 60 Second stopper member

Claims (1)

A side member extending in the front-rear direction on both sides of the vehicle, a vehicle body elastically supported on the side member, a stopper device provided on the side member, and a protrusion provided on a vehicle body part facing the stopper device;
The stopper device includes a first stopper member including a wall portion facing the protruding portion with a space between the protruding portions and a support portion orthogonal to the wall portion, and a back surface of the wall portion of the first stopper member. A vehicle body structure for a vehicle with a frame, comprising a second stopper member having a tapered portion opposed to the second stopper member.

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