JPH076003Y2 - Vehicle suspension system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a suspension device for a vehicle having an A-type arm.

[Prior art]

Various types of suspension devices have been adopted as a suspension device that connects and supports a vehicle body to the wheels of an automobile and absorbs the impact of unevenness on the road surface to improve riding comfort. For example, A as described in Japanese Utility Model Publication No. 59-121212
The die arm is widely adopted as it has excellent compatibility with various suspension devices.

The A-shaped arm is substantially A-shaped in a plan view and is connected to a knuckle spindle member on the wheel side at the top thereof,
A pair of base end portions are provided with pivotally-supported bush support portions directed in the front-rear direction, and these pivotally-supported bush support portions are respectively coupled to the vehicle-body-side cross member and the subframe via rubber bushes.

Conventionally, the above-mentioned A-shaped arm has a structure in which two steel plate members formed in a substantially symmetrical shape in the vertical direction are welded and joined to each other by joint flanges formed in an outwardly projecting shape on their outer peripheral portions.

[Problems to be solved by the device]

When the automobile is running, a large rearward load is applied to the wheels due to the unevenness of the road surface, and the large load is supported through the A-shaped arm body and the pair of pivotally attached bush support portions. The outer peripheral portion of the A-shaped arm near the pair of front and rear pivoting bush support portions is curved, and the curved portion near the front pivoting bush support portion on the front side is opened when the large load is applied. A large load acts. At this time, there is a problem that a large tensile stress is generated due to stress concentration due to a bending moment at the outer edge of the joint flange portion of the curved portion, and a crack is generated in the joint flange.

The present invention is to provide a suspension device including an A-shaped arm that does not cause a crack in a curved portion near the pivotally supported bush support portion.

[Means for Solving the Problems]

A vehicle suspension device according to the present invention is a vehicle suspension device having an A-type arm, wherein the A-type arm is composed of upper and lower two plate members joined together at an outer peripheral portion thereof, and the A-type arm has a pivotally supported bush support. The curved outer peripheral portion near the portion is not provided with a joining flange for joining the upper and lower plate members, but is provided with a reinforcing plate member that is joined across the upper and lower plate members.

[Action]

In the vehicle suspension device according to the present invention,
Since the curved outer peripheral portion of the die arm in the vicinity of the pivotally supported bush supporting portion is not provided with a joining flange, but is provided with a reinforcing plate member that is joined across two upper and lower plate members, the section modulus of that portion is In addition to relaxing the maximum stress that occurs as the size increases,
Since a maximum stress is locally generated and a plate-like free end portion where cracks are likely to occur does not exist and the maximum stress is dispersed in the reinforcing plate member having a large cross-sectional area, no crack occurs.

[Effect of device]

According to the suspension device for a vehicle of the present invention, as described above, the A-type arm is pivotally attached by the simple structure of providing the reinforcing plate member which is joined to the upper and lower plate members instead of the joining flange. The strength of the curved outer peripheral portion in the vicinity of the bush supporting portion can be increased to reliably prevent the occurrence of cracks. Further, since the curved portion having the strictest strength can be effectively reinforced, it is possible to reduce the weight by reducing the plate thickness of the A-type arm.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a front suspension device for a vehicle suspends left and right front wheels 3 on a vehicle body 1 to regulate the posture of the front wheels 3 and buffers external forces acting on the front wheels 3 in the front-rear direction and the left-right direction. It is for transmitting the load from the vehicle body 1 to the front wheels 3. The front suspension device in the present embodiment is a strut-type independent suspension device with an A-type arm, and a cross member 2 arranged at the lower part of the front part of the vehicle body 1.
A pair of left and right A-shaped arms 4 for connecting the left and right front wheels 3 respectively
Basically, a pair of left and right struts 5 composed of hydraulic shock absorbers for connecting the inner arms of the axle support member 10 to which the front wheels are fixed to the vehicle body 1 and a coil spring 6 mounted on each strut 5 are basically provided. It is configured.

2 and 3 show a pair of left and right A-shaped arms 4 for connecting the right front wheel 3 to each other. The A-shaped arms 4 are substantially A-shaped in plan view formed by press-forming a steel plate. The pair of upper and lower plate members 4A and 4B are joined to each other by welding the joint flange portions 7A and 7B formed so as to project to the outer periphery of the upper and lower plate members 4A and 7B. Since the lower plate member 4B is formed so as to bulge downward from the joining flange 7, the A-shaped arm 4
Has a closed cross-section structure with excellent strength and rigidity. A mounting portion 8 for connecting to an axle support member via a ball joint is formed at an outer end portion of the A-type arm 4 on the front wheel 3 side,
A bracket 13 for connecting the stabilizer 9 is fixed to the upper plate member 3A at a portion slightly inside the mounting portion 8. At the front end and the rear end of the inner end of the A-shaped arm 4 on the center side of the vehicle body, cylindrical pivoting bush support portions 11 and 12 are formed in the front-rear direction.

Joining flanges 7A and 7A are provided at the front edge portion and the rear edge portion of the upper plate member 4A and the lower plate member 4B, and the rear portion approximately 2/3 of the inner edge portion.
B is formed, the width of the joining flange 7B of the lower plate member 4B is formed smaller than the width of the joining flange 7A of the upper plate member 4A, and the edge of the joining flange 7B is continuously welded to the joining flange 7A. Thus, the upper plate member 4A and the lower plate member 4B are integrally connected.

From the middle of the inner edge of the A-shaped arm 4 to the pivotally connected bush support
Joint flanges 7A and 7B are not formed on the inner edge over 11.
The upper and lower plate members 4A and 4B respectively extend forward in the form of being separated from the middle portion and are joined to the pivotally attached bush support portion 11.

Here, as will be described later, the inner end portion of the A-type arm 4 is connected to the cross member 2 fixed to the vehicle body 1 via the pivotally-supported bush support portions 11 and 12, and when the automobile is running, the front wheel may be damaged due to unevenness of the road surface. When a large rearward external force is applied to 3, a large tensile stress due to a bending moment is generated in the curved portion 14 near the pivotally connected bush support 11.

Therefore, of the inner edge portion of the arm 4 on the vehicle body center side, the curved portion 14 near the pivoting bush support portion 11 and a predetermined range portion on the rear side thereof are reinforced more strongly than the joint by the joint flanges 7A and 7B. Therefore, the reinforcing member 16 is joined across the upper plate member 4A and the lower plate member 4B.

As shown in FIGS. 4 to 6, the reinforcing plate member 16 is formed in a substantially U-shaped cross section between the pivot bush 11 and the front end portions 15 of the joint flanges 7A and 7B.
The edge portion of a is continuously welded to the upper plate member 4A, and the edge portion of the lower flange portion 16b is continuously welded to the lower plate member 4B, and the vertical wall portion 16c has upper and lower plate members 4A and 4A. It is arranged in contact with the inner side surface of 4B.

Then, of the reinforcing plate member 16, the joining flange 7A
The portion extending from the front end portion 15 of 7B rearward by a predetermined length is vertically extended from the front end portion 15 to an extension portion 16d that covers the shoulder portion of the upper plate member 4A and an extension portion 16e that covers the shoulder portion of the lower plate member 4B. The extension part 16d is formed in a shape in which the upper flange part 16a is slightly widened toward the joining flange 7 side and is welded and joined to the upper plate member 4A similarly to the upper flange part 16a, and the extension part 16e is the lower flange part. 16b is formed in a shape that is slightly widened toward the joint flange 7 side, and is welded to the lower plate member 4B in the same manner as the lower flange portion 16b.

The pivoting bush support portions 11 and 12 are cylindrical members 17 and 18, respectively.
Is welded to the upper and lower plate members 4A and 4B, and a bush member formed by fixing a double rubber bush to the outside of the intermediate pipe is fixedly fitted into each pivotally-attached bush support portion 11 and 12. Further, brackets 19 and 20 are fixed to the lower surface side of the cross member 2 at positions corresponding to the pivotally attached bush support portions 11 and 12, respectively, and the intermediate pipe of each pivotally attached bush support portions 11 and 12 and the corresponding brackets 19 and 20 are attached. Bolt 21 across the pivot hole of
・ Pivoting bush support by inserting and fastening 22
11 and 12 are elastically connected to the cross member 2.

In the above suspension apparatus, when a large rearward external force acts on the front wheels 3 due to unevenness of the road surface when the vehicle is running, a forward supporting reaction force F ₁ acts on the pivoting bush support portion 11 of the A-type arm 4. And also the pivoting bush support
A forward supporting reaction force F ₂ and an outward supporting reaction force F ₃ act on 12, so that a large bending tensile stress is generated mainly on the bending portion 14 by the reaction force F ₁ and the reaction force F _3. However, since the curvature of the curved portion 14 is considerably large, a large stress is generated with some concentration of stress, but as described above, the joint flange 7 is not provided over the curved portion 14 and the predetermined range portion on the rear side thereof. Reinforcing plate member
Since 16 is provided so as to straddle the upper plate member 4A and the lower plate member 4B, the section modulus of that part becomes large and the maximum value of the stress decreases, and the joint flange at the part where the maximum stress occurs.
7A and 7B cracks are likely to occur.There is no plate-shaped free end and there is a reinforcing plate member 16 having a large cross-sectional area, so that stress is widely dispersed, and cracks occur in the bending member 14 due to reasons such as There is no such thing. Further, the reinforcing plate portion 16 extends rearward of the front end portion 15 of the joining flange 7, but since the section modulus does not decrease discontinuously, the joining flange 7 is provided near the front end portion 15 of the joining flange 7. No cracks occur in the.

In addition, the joint flange 7 of the curved portion 23 near the pivot bush 12
Since there is a compressive stress, not a tensile stress, there is no problem of cracking. However, the pivoted bush support
Since bending tensile stress is generated in the outer curved portion 24 near 12, the reinforcing plate member may be provided in the curved portion 24 similarly to the reinforcing plate member 16, and the inner curved portion 23 is reinforced similarly. It is also possible to provide a plate member.

If the reinforcing structure of the reinforcing plate member 16 is adopted, the cross-sectional structure can be effectively strengthened with a relatively small member, so that the plate thickness of the upper and lower plate members 4A and 4B can be reduced, etc.
It is also possible to reduce the weight of.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a perspective view of a front and rear suspension of an automobile, and FIG.
FIG. 3 is a plan view of the mold arm, FIG. 3 is a view in the direction of arrow III of FIG. 2, FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 2, FIG. 5 is a cross-sectional view taken along line VV of FIG. 2, and FIG. FIG. 2 is a sectional view taken along line VI-VI of FIG. 4 ... A type arm, 4A ... upper plate member, 4B ... lower plate member,
7 ... Joint flange, 11 ... Pivot bush support, 16 ...
... Reinforcing plate member.

Claims (1)

[Scope of utility model registration request] 1. A vehicle suspension device having an A-shaped arm, wherein the A-shaped arm is formed by joining two upper and lower plate members at an outer peripheral portion thereof, and the A-shaped arm is curved near a pivoting bush support portion. A suspension device for a vehicle, characterized in that a reinforcing plate member joined to the upper and lower two plate members is provided on the outer peripheral portion without providing a joining flange for joining the upper and lower plate members.