JPH11115429A - Suspension arm structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-weight and strong suspension arm. SOLUTION: This suspension arm 1 is constituted in such a way that a joint arm 2 and a rear bush arm 4 are integrally molded by overlapping an upper plate 1a and a lower plate 1b and its cross section is a closed cross section. A spring seat 5 is provided on a top face of the upper plate 1a. An intermediate plate 6 is welded between the spring seat part 5 and the lower plate 1b. A through hole 6a is drilled in a central part of the intermediate plate 6, and a cylindrical reinforcing collar 8 welded between a bamboo stopper of the upper plate 1a and a bottom face of the lower plate 1b is inserted into this through hole 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension arm structure which is a component of a suspension portion of an automobile and is formed by forging.

[0002]

FIG. 6 shows a strut-type suspension arm 51 of an automobile. The suspension arm 51 is a device for suspending an axle of a tire 52 and a frame of an automobile. A knuckle spindle (not shown) is interposed at a tip end of a joint arm 53 to which a ball joint is attached. Is linked to Further, the front bush arm 54 and the rear bush arm 55 of the suspension arm 51 are attached to a body-side suspension arm member (not shown) by inserting bolts into the respective bush fittings 54a and 55a. As shown in the exploded view of FIG. 7, the suspension arm 51 formed by forging mainly includes an upper plate 51a and a lower plate 51b, and a ball joint 56 is sandwiched therebetween and screwed with a bolt 57.

In the suspension arm having such a shape, a portion where stress is concentrated is determined in each state where a vertical load, a braking load, and a cornering load are applied to the vehicle body during traveling. Stress concentrates on the roots of the joint arm 53 and the rear bush arm 55 when the vehicle is up and down, at the root of the front bush arm 54 during braking, and at the root of the joint arm 53 and the rear arm 55 during cornering. The largest load among them is the vertical load of the vehicle body.

[0004]

It is necessary to prevent the suspension arm from being damaged even if a load due to an excessive impact load is applied to each part of the suspension arm.
The suspension arm is a ball joint 5
If the mounting of 6 is performed by bolting, the manufacturing cost increases. As mentioned above, there is a suspension type forged product in which the joint is welded. However, in the case of a two-piece structure with upper and lower plates, it is impossible to weld the joint by welding. There is a fact that a patch must be used. The present invention has been made in view of the above-mentioned problem, and the mounting of a ball joint is performed by welding, and a portion to which a load is applied is increased in strength, and a portion to which a load is not applied has an appropriate strength, and the weight is increased. It is an object of the present invention to provide a suspension arm structure which is light and does not require material cost.

[0005]

In order to achieve the above object, the present invention comprises a joint arm at one end for supporting a wheel side via a ball joint, and the other end is branched into two branches, each of which is connected to a vehicle body. A suspension arm, comprising: a supported front bush arm and a rear bush arm; and a suspension arm surface formed with a coil spring seat disposed between the suspension arm and the body. Along with providing the above-mentioned spring seat between the and the joint arm, these two arms are overlapped with the upper plate and the lower plate to form a closed cross section, and the front bush arm is made less rigid than between the two arms, It is welded between the arms.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A suspension arm structure according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a forged coil spring separated type lower suspension arm 1 according to the present invention. The suspension arm 1 has a joint arm 2 that supports the axle side of the vehicle body with a knuckle joint (not shown) interposed at one end. Suspension arm 1
Is bifurcated on the inner side of the vehicle body, a front bush arm 3 is provided on the front side, and a rear bush arm 4 is provided on the rear side.

FIG. 2 is an exploded view of the suspension arm 1. As shown in the drawing, the joint arm 2 and the rear bush arm 4 have a closed cross-sectional shape (box shape) in which the upper plate 1a and the lower plate 1b are overlapped and integrally formed. A spring seat 5 is provided on the upper surface of the upper plate 1a as a spring seat for a coil spring (not shown) disposed between the suspension arm 1 and the vehicle body. Between 5 parts of the spring seat and the lower plate 1b,
As shown in FIG. 3, the middle plate 6 is fixed, one side of which is welded to the side surface of the lower plate 1b and the other side of which is welded to the bottom surface of the lower plate 1b. The middle plate 6 is provided with a through hole 6a at the center thereof. The first cylindrical hole is welded between the lower surface of the van booster 7 of the upper plate 1a and the upper surface of the lower plate 1b. Are inserted.

As shown in FIG. 1, a cylindrical second reinforcing collar 9 is provided between the spring seat 5 and the lower joint 12 of the joint arm 2, and is attached to the upper and lower plates 1a and 1b shown in FIG. The holes 10 and 11 are fixed to the edges of the holes 10 and 11 by welding. The reinforcing collar 9 is disposed on a line (or almost on the line) connecting the tire-side support portion of the joint arm 2 and the mounting center of the rear bush arm 4 and between the spring seat 5 and the joint arm 2. I do. Specifically, it is arranged in a portion where damage is likely to occur due to a vertical load. As shown in FIG. 2, mounting portions 12a and 12b of the lower joint are provided on the joint arm 2 side of the upper and lower plates 1a and 1b, respectively, and the lower joint 12 is fixed by welding so that the lower joint 12 is sandwiched therebetween. You. The upper and lower plates 1a,
A bush metal fitting 14 for mounting the vehicle body is fixed to the rear bush arm 4 of 1b.

The front bush arm 3 has a U-shaped cross section, and the joint arm 2 of the upper and lower plates 1a and 1b
And the rear bush arm 4 is fixed by welding to the side of the spring seat 5. The strength of the front bush arm 3 is
Rigidity is lower than that of the upper and lower plates 1a, 1b superposed, and a bush fitting 15 is fixed to the end of the front bush arm 3.

The configuration of the suspension arm structure according to the embodiment of the present invention has been described above. Next, its operation will be described. As described above, the largest load among the loads applied to the suspension arm 1 is a load in the vertical direction of the vehicle body (when the vehicle is fully bumped), and this load is the root of each of the joint arm 2 and the rear bush arm 4. It takes Suspension arm 1
The joint arm 2 and the rear bush arm 4 have a closed section formed by the upper and lower plates 1a and 1b, and have high rigidity. In the present embodiment, the section rigidity is increased by further attaching the middle plate 6. Since the cross-sectional rigidity between the center of attachment of the joint arm 2 and the spring seat 5 is important, this method simply uses the upper and lower plates 1.
The cross-sectional rigidity is larger than when patches are applied to a and 1b. This is particularly effective when reinforcement with a patch is not possible.

Reinforcement collars 8, 9 are provided between the spring seat 5 and the spring seat 5 and the joint arm 2.
And the rigidity is further increased. Therefore, the suspension arm 1 can sufficiently withstand the load in the vertical direction of the vehicle body. The same applies to cornering. At the time of braking, a load is applied to the base of the front bush arm 3, but since this load is smaller than the vertical load or the like, the load can sufficiently withstand even if the rigidity is smaller than that between the joint arm 2 and the rear bush arm 4. be able to.

As described above, in the present embodiment, the cross-sectional rigidity of the portion of the suspension arm that receives the most severe vertical load is increased, and the portion to which a large load is not applied has appropriate rigidity, so that the strength balance of the suspension arm is improved. Well done. By making the upper and lower plates 1a and 1b closed sections and adding the middle plate 6 and the reinforcing collars 8 and 9, the thickness of the upper and lower plates 1a and 1b can be reduced, and the thickness of the front bush arm 3 can be reduced. It is possible to reduce the weight without increasing the thickness. In addition, the size of the lower joint 12 of the joint arm 2 can be made smaller than that of a conventional forged product, so that bolting can be eliminated and fixed by welding.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications and changes can be made based on the technical concept of the present invention.
The suspension arm 20 shown in FIG. 4 includes a joint arm 21 and front and rear side bush arms 22, 23,
0a is integrally formed, and the lower plate is a lower plate 2 forming the joint arm 21 and the rear bush arm 23.
0b and the lower plate 20c forming the front bush arm 22 are separate. The lower plate 20 is used to reinforce the space between the joint arm 21 and the rear bush arm 23.
The rib 20d is erected on b. The ribs 20d are arranged at a line a connecting the mounting center of the joint arm 21 and the mounting center of the rear bush arm 23 and a line b connecting the front and rear bush arms 22, 23 from the mounting center of the joint arm 21. It is within the range of a line c drawn by a perpendicular line.

In this modification, by welding the upper edge of the rib 20d to the upper plate 20a, the cross section between the joint arm 22 and the rear bush arm 23 becomes a closed cross section, and the rigidity therebetween increases. In the suspension arm 30 shown in FIG. 5, the space between the joint arm 31 and the rear bush arm 32 is divided into two sections by upper and lower plates 30a and 30b to form a closed cross section.
It is divided into two by 0c and 30d. In this modification, the front bush arm 33 has a closed cross section, so that it can be formed with a thin plate. In addition, although the said intermediate | middle plate 6 is abolished in the said modification and this modification, you may attach it.

[0015]

As described above, according to the present invention, the joint arm and the rear bush arm are formed in a closed cross section by overlapping the upper plate and the lower plate, and the front bush arm is more rigid than between the two arms. Is reduced, the rigidity of the portion where the load of the suspension arm is large can be increased, and the portion where the load is not large is appropriately rigid, so that the strength balance is improved. By providing a lower plate and a middle plate that forms a closed cross section with the lower plate, the strength is increased and the patch can be eliminated. Further, by providing the second reinforcing member between the support portion of the joint arm and the coil spring seat, the rigidity is further increased with respect to the load in the vertical direction.

[Brief description of the drawings]

FIG. 1 is a plan view of a suspension arm having a suspension arm structure according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the suspension arm of FIG.

FIG. 3 is a sectional view taken along line XX in FIG.

FIG. 4 is an exploded perspective view of a suspension arm having a suspension arm structure according to a modification of the present invention.

FIG. 5 is an exploded perspective view of a suspension arm having a suspension arm structure according to another modification of the present invention.

FIG. 6 is a plan view of a suspension section of a conventional suspension arm structure.

FIG. 7 is an exploded perspective view of a suspension arm having a conventional suspension arm structure.

[Explanation of symbols]

 1,20,30 Suspension arm 1a Upper plate 1b Lower plate 2 Joint arm 3,22,33 Front bush arm 4,23,31 Rear bush arm 5 Spring seat 6 Middle plate 6a Through hole 8,9 Reinforcement collar 12 Lower joint 12a, 12b mounting part

Claims (4)

[Claims] An end provided with a joint arm for supporting the wheel side via a ball joint, the other end branched into two branches, and a front bush arm and a rear bush arm each supported on the vehicle body side; A suspension arm having a coil spring seat disposed between the suspension arm and the body on a suspension arm surface, the spring arm being provided between the rear bush arm and the joint arm; The upper plate and the lower plate are overlapped to form a closed cross section, and the front bush arm is made less rigid than between the two arms, and is welded between the two arms. The suspension arm structure according to the above. 2. Under the coil spring seat,
An intermediate plate is provided which is welded to the lower plate to form a closed cross section, and a first reinforcing member which penetrates a hole provided in the intermediate plate and connects the coil spring seat surface and the lower plate surface is fixed. The suspension arm structure according to claim 1. 3. A cross-section of the suspension arm between the support portion of the joint arm and the coil spring seat, wherein a cross-section having a small rigidity against a load is provided with a second reinforcing member for connecting the upper plate and the lower plate. The suspension arm structure according to claim 2. 4. The suspension plate according to claim 1, wherein the entire upper plate of the suspension arm is formed of one sheet, and the lower plate is provided with a rib for providing a closed cross section between the two arms, and the rib is welded to the upper plate. The suspension arm structure according to the above.