GB2205074A

GB2205074A - Vehicle wheel suspension arm assembly

Info

Publication number: GB2205074A
Application number: GB08712256A
Authority: GB
Inventors: Laurence Frederick Topping; Michael Colin William Johnson; Frederick David Connor
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1987-05-23
Filing date: 1987-05-23
Publication date: 1988-11-30
Anticipated expiration: 2007-05-23
Also published as: GB2205074B; GB8712256D0

Abstract

The assembly comprises a sheet metal bracket 10 which is bolted to a vehicle body and an arm 14 which is located between plates 28 and 30 of the bracket and has an outbound end for supporting a vehicle wheel. Two compliant bushes 20 and 22, both if which have their axes vertical, receive bolts connecting the bracket and the arm. The bushes have particular forms (Figs. 2 and 3) to provide the required compliance of the assembly. <IMAGE>

Description

SUSPENSION ARM ASSEMBLY This invention relates to a suspension arm assembly for a motor vehicle wheel. The invention is particularly, but not exclusively, useful for a front wheel suspension, and can be used for a steerable, driven wheel.

According to the present invention there is provided a suspension arm assembly comprising a bracket adapted to be bolted to vehicle bodywork and an arm mounted in the bracket and having an outboard end for supporting a vehicle wheel, wherein the arm is L shaped with one limb of the L extending generally parallel to the vehicle centre line and the other limb extending generally at right angles thereto, said one limb being connected to the bracket by two spaced connections, each connection comprising a resiliently mounted bush fitted in the arm with the axis of each bush generally at right angles to the plane of the arm and a line joining the centre lines of both bushes being generally parallel to the vehicle.

centre line, and wherein the bracket has upper and lower plates and the bushes are received between the upper and lower plates, with bolts being passed through the plates and the bushes to complete the connections.

The bracket is preferably a box structure fabricated from sheet metal.

The arm is preferably also fabricated from sheet metal and is made by welding together two plates. The plates preferably have sockets for receiving the bushes as pressfits in the sockets. The sockets preferably have a lip to add strength to the arm sockets and to limit insertion depth of the bushes, and an interruption in the lip to allow for removal of the bushes for service needs.

The arm preferably also has a socket for receiving a ball joint, with the ball joint being intended to carry a wheel of the vehicle through a knuckle. The socket for the ball joint is preferably adapted to receive a ball joint either way up, so that the arm can be non-handed until the ball joint is put in place.

Preferably the one of the bushes which, in use, will be nearer the front of the vehicle is harder than the rear bush. The front bush preferably has a spacer tube with a spherical enlargement around it embedded in a body of rubber which bonds the spacer tube to an annular outer ring. The annular outer ring is additionally reduced in diameter at each end to allow higher articulation. The rear bush may be solid, but is preferably a void bush.

The bracket may include mounting points for a roll bar.

The L shaped arm is preferably arranged so that, in use, the limb which extends generally at right angles to the car centre line is forwardmost in the vehicle.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which; Figure 1 is an exploded view of a suspension arm assembly in accordance with the invention; Figures 2 and 3, are respectively, sections through front and rear bushes for the assembly shown in Figure 1; and Figure 4 is a section through the arm, on the line IV-IV.

Figure 1 shows a bracket 10 which will be secured to the bodywork of a vehicle by bolts passed through five holes 12, and an arm 14. The arm 14 has two sockets 16 and 18 for receiving two bushes 20 and 22. The arm also has a socket 24 for receiving a ball joint 26.

In use, the bushes 20 and 22 are inserted into the sockets 16 and 18 and the arm is then fitted into the bracket between an upper plate 28 and a lower plate 30. The arm and the bracket are connected together by bolts which pass through the holes 32 in the bracket and through central spacer tubes 34 in the bushes 20 and 22. In this way the arm is connected to the bracket, and the outwardly directed limb 36 of the arm can move up and down by taking advantage of the compliance of the bushes 20 and 22.

The characteristics of the bushes can be designed independently of the arm, and the overall compliance of the assembly can easily by changed by using bushes with different characteristics. Figures 2 and 3 show examples of suitable bushes. Figure 2 shows a front bush which has a high lateral and radial stiffness, but low conical stiffness so that up and down movement of the arm can take place without a great deal of resistance. This is achieved by the spherical swelling 38 on the tube 34. A body 40 of rubber is then bonded between the central spacer tube 34 and an outer annular ring 42.

The rear bush shown in Figure 3 is soft and has voids 44 to allow the necessary fore-and-aft compliance.

Figure 4 shows schematically how a representative bush 22 is inserted into a socket 18 in the arm 14. The socket 18 is plunged to a size which will form an interference fit with the outer ring 42 of the bush, and the bush is then simply pressed into place until it reaches a lip 46 which limits insertion movement. If it should be necessary to remove the bush, this can be done by inserting a suitable tool through a cut-out-48 around the periphery of the lip 46. The socket 18 is thus formed directly in the sheet metal of the arm, and no separate mounting sleeve needs to be inserted in the socket to receive the bush.

An arrow 50 in Figure 1 lies in the direction of the centre line of a vehicle in which the assembly will be installed and shows the intended orientation of the parts of the assembly. The head of the arrow points towards the front of the vehicle.

It will be clear from Figure 1 that the ball joint 26 can be inserted and fastened in the socket 24 either way up.

Until the joint has been inserted, the arm 14 is nonhanded apart from the lips 46, and it is immaterial whether these lips are positioned above or below their respective bushes once the assembly is complete. The arms are therefore effectively non-handed for manufacturing purposes.

The arm 14 also has a through hole 50 to allow access from below to the bolt in the hole 12a which secures the bracket to the vehicle body. Thge bracket also has a mounting location 52 where a roll bar can be attached.

Both arm and bracket are made from two pieces of flat sheet material suitably formed and spot welded together.

The assembly thus described provides an effective wheel suspension without undue cost or manufacturing complexity.

The suspension characteristics can easily be controlled by suitable selection of the bushes.

Claims

1. 9 suspension arm assembly for a vehicle, comprising a bracket adapted to be bolted to the vehicle bodywork and an arm mounted in the bracket and having an outboard end for supporting a vehicle wheel, wherein the arm is L shaped with one limb of the L extending generally parallel to the vehicle centre line and the other limb extending generally at right angles thereto, said one limb being connected to the bracket by two spaced connections, each connection comprising a resiliently mounted bush fitted in the arm with the axis of each bush generally at right angles to the plane of the arm and a line joining the centre lines of both bushes being generally parallel to the vehicle centre line, and wherein the bracket has upper and lower plates and the bushes are received between the upper and lower plates, with bolts being passed through the plates and the bushes to complete the connections.

2. An assembly as claimed in Claim 1, wherein the bracket is a box structure fabricated from sheet metal.

3. an assembly as claimed in Claim 1 or Claim 2, wherein the arm is fabricated from sheet metal and is made by welding together two plates.

4. 9n assembly as claimed in Claim 3, wherein the plates have sockets made from the material of the plates for receiving the bushes as press fits in the sockets.

5. An assembly as claimed in Claim 4, wherein the sockets have a lip to limit insertion depth of the bushes, and an interruption in the lip to allow for removal of the bushes for service needs.

6. An assembly as claimed in any preceding claim, wherein the arm also has a socket for receiving a ball joint, the socket being adapted to receive the ball joint either way up.

7. An assembly as claimed in any preceding claim, wherein the bush which, in use, will be nearer the front of the vehicle is harder than the rear bush.

8. An assembly as claimed in Claim 7, wherein the front bush has a spacer tube with a spherical enlargement around it embedded in a body of rubber which bonds the spacer tube to an annular outer tube.

9. An assembly as claimed in Claim 7, wherein the rear bush is a void bush.

10. An assembly as claimed in any preceding claim, wherein the-bracket includes mounting points for a roll bar.

11. An assembly as claimed in any preceding claim, in which the L shaped arm is preferably arranged so that, in use, said other limb which extends generally at right angles to the car centre line is forwardmost in the vehicle.

12. A suspension arm assembly substantially as herein described with reference to and as shown in the accompanying drawings