JPH0885473A - Sub-frame structure for automobile - Google Patents

Abstract

PURPOSE: To smoothly bend the vertical member of a sub-frame at the time of a collision. CONSTITUTION: A vertical member 6 extended in the vehicle body longitudinal direction of a parallel cross-shaped sub-frame provided at the front section of an automobile is bent so that an intermediate section 6c is located lower than the front and rear end sections 6a, 6b. The vertical member 6 is fastened to the vehicle body side at three points of an intermediate connecting bracket 9 erected at the intermediate section 6c and the front and rear end sections 6a, 6b. Groove-like bending beads 10a, 10b nearly perpendicular to the axial direction are provided respectively at different positions in the axial direction on the upper face and lower face between the front end section 6a and the intermediate connecting bracket of the vertical member 6. When the buckling load is generated by a collision, the bending beads 10a, 10b can serve as bending points, and the downward bending deformation of the vertical member 6 can be smoothly performed at the time of a collision.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile subframe structure, and more particularly to an automobile subframe structure having a vertical member extending in the front-rear direction of a vehicle body.

[0002]

2. Description of the Related Art Some automobiles use a subframe that supports a suspension, and when the subframe is arranged at the front of the automobile, some subframes are equipped with an engine and a suspension. In the structure of the sub-frame, a vertical member extending in the front-rear direction on the left and right of the vehicle body and a horizontal member connecting the front end portions of the both vertical members and the rear end portions are formed in a cross beam shape. There is something.

In the case of using the sub-frame as described above, for example, as disclosed in Japanese Utility Model Publication No. 61-39651, the vertical member of the sub-frame is deformed together with the deformation of the body at the time of collision, and the impact is generated. I try to absorb power. In order to deform the vertical member due to the buckling load at the time of collision, there is a device in which a portion (bead) that triggers bending is provided on the vertical member as disclosed in the above publication. Further, as shown in FIG. 3 which schematically shows the side surface of the vertical member, the vertical portion 11 is vertically arranged so that the intermediate portion 11c is located below the front and rear end portions 11a and 11b which are connected to the vehicle body side. There is one in which the member 11 is formed by bending, and the main cross-sectional view center axis is offset downward so that it can be bent downward due to a buckling load at the time of collision.

Further, the vertical member of the sub-frame is shown in FIG.
In addition to supporting at two points on both the front and rear ends as shown in FIG. 3, an intermediate connecting bracket is erected on the intermediate portion and supported at three points via the intermediate connecting bracket. By doing so, the rigidity of the sub-frame can be increased, and the degree of freedom of attachment to the vehicle body can be improved. However, since the intermediate point of the vertical member is connected to the vehicle body side through the intermediate connecting bracket, there arises a problem that it becomes difficult to bend downward during buckling deformation.

[Problems to be Solved by the Invention]

In view of the above problems of the prior art, a main object of the present invention is to provide a subframe structure for an automobile capable of smoothly bending due to buckling at the time of collision.

[0006]

According to the present invention, there is provided a subframe structure for an automobile having a vertical member extending in the front-rear direction of a vehicle body, wherein the vertical member has an intermediate portion. There is an intermediate connecting bracket which is formed by bending so as to be positioned below the vehicle body with respect to the front and rear end portions, and which is provided upright in the intermediate portion, and at each point of the front and rear end portions and the intermediate connecting bracket. A plurality of bending beads that are coupled to the vehicle body and that are substantially orthogonal to the axial direction are formed at a plurality of different positions in the axial direction of the vertical member between the intermediate coupling bracket and the front end portion. It is achieved by providing a subframe structure for an automobile, characterized in that

[0007]

According to this structure, when a buckling load occurs due to a collision, a portion between the front end of the vertical member and the intermediate connecting bracket is provided for bending at a plurality of different positions in the axial direction. Since each bead for bending can be bent using the bead as a bending point, the bending deformation of the vertical member at the time of collision can be smoothly performed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view showing a front frame of an automobile to which the present invention is applied. In a bonnet (not shown), left and right front side frames 2.3 extending in the front-rear direction are provided. It is provided. The front side frames 2 and 3 rise obliquely upward from a floor panel side of a vehicle compartment (not shown) and then extend substantially horizontally to the front part of the hood.

A sub frame 4 is attached to the lower side of the front side frames 2 and 3, and an engine 5 for driving front wheels is supported by the sub frame 4.
The sub-frame 4 is formed in a cross beam shape as shown in the drawing, and the left and right vertical members 6 extending in the front-rear direction of the vehicle body.
And a front lateral member 7 and a rear lateral member 8 that connect the front end portions of the vertical members 6 and the rear end portions of the vertical members 6, respectively.

The vertical member 6 is joined to the front side frame 2 by a fastening member (not shown) at three points, namely, front and rear ends 6a and 6b and an intermediate connecting bracket 9 provided upright on the intermediate portion 6c. The vertical member 6 is shown in FIG.
As shown in (a), the intermediate portion 6c is connected to the front and rear end portions 6
It is formed by bending the vicinity of the front and rear end portions 6a and 6b so as to be located below the vehicle body with respect to a and 6b.

As shown in FIG. 2 (a), the vertical member 6 has two positions between the intermediate connecting bracket 9 and the front end portion 6a and at different positions with respect to the axial direction of the vertical member 6. , And bending beads 10a and 10b are provided respectively. These bending beads 10a and 10b are processed at the same time when the vertical member 6 is pressed into a groove shape in a direction substantially orthogonal to the axial direction of the vertical member 6. One bending bead 10a is provided on the front end portion 6a side of the upper surface of the vertical member 6,
The other bending bead 10b is provided on the lower surface of the vertical member 6 on the side of the intermediate coupling bracket 9.

A bending bead 10 is also provided between the intermediate connecting bracket 9 of the vertical member 6 and the rear end portion 6b in the same manner as described above.
c.10d is provided. Then, one bending bead 10c is provided on the upper surface of the vertical member 6 on the side of the intermediate connecting bracket 9.
And the other bending bead 10d is provided on the rear surface 6b side of the lower surface of the vertical member 6.

In the vertical member 6 thus formed, when a buckling load is applied at the time of collision, each bending bead 1 is bent.
Deformation as shown by the solid line in FIG. 2 (b) may occur triggered by 0a to 10d. Each bending bead 10a, 10b provided on the front side of the intermediate connecting bracket 9
Is for causing the vertical member 6 to be deformed before the external impact force directly acts on the engine 5, and each bending bead 10 provided on the rear side of the intermediate connecting bracket 9.
c · 10d is for causing the vertical member 6 to be deformed when an external impact force acts on the engine 5 and the engine 5 is about to be displaced rearward. Can be absorbed.

By providing the bending beads 10a to 10d as in this embodiment, it is possible to smoothly bend the vertical member 6 downward. Note that when a stronger impact force is applied, it can be bent more greatly as shown by the imaginary line in FIG. 2 (b).

[0016]

As described above, according to the present invention, the bending bead, which serves as a bending point due to buckling at the time of collision, is provided at a plurality of axially different positions between the intermediate connecting bracket and the front end of the vertical member. Since the vertical member is connected to the front and rear end portions and the intermediate portion, the bending due to buckling can be smoothly performed, which affects the buckling deformation of the body. It is possible to appropriately absorb the impact force at the time of a collision.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a front frame of an automobile to which the present invention is applied.

FIG. 2A is a diagram schematically showing a side surface of a vertical member of a subframe, and FIG. 2B is a diagram showing a bent state of the vertical member.

FIG. 3 is a schematic side view showing an example of a conventional vertical member.

[Explanation of symbols]

 2.3 Front side frame 4 Subframe 5 Engine 6 Vertical member 6a Front end portion 6b Rear end portion 6c Middle portion 7 Front lateral member 8 Rear lateral member 9 Intermediate connecting bracket 10a, 10b, 10c, 10d Bending beads 11 Vertical member 11a front end part 11b rear end part 11c middle part

Claims (1)

[Claims] 1. A subframe structure for an automobile having a vertical member extending in the front-rear direction of a vehicle body, wherein the vertical member is bent so that an intermediate portion is located below the front and rear end portions of the vehicle body. And an intermediate connecting bracket which is formed upright in the intermediate portion, is connected to the vehicle body at each point of the front and rear end portions and the intermediate connecting bracket, and the intermediate connecting bracket and the front end. A subframe structure for an automobile, characterized in that a plurality of bending beads are formed at a plurality of positions different from each other in the axial direction of the vertical member between the parts, and the bending beads are oriented substantially orthogonal to the axial direction.