Background to the Invention Vehicle suspensions customarily utilise means to provide a dampened movement between a wheel axle mechanism and the vehicle body or chassis.

Such means can include spring based mechanisms, usually associated with shock absorbers, as well as air bags or other types of fluid suspension. Whatever means is used, such suspension means are generally affixed to a chassis on the underside of the relevant vehicle. This requires the vehicle chassis to be custom designed to cooperate with a particular suspension means.

In addition where a concentric spring and shock absorber means is used between a mount on a trailing arm and a vehicle chassis it is common for a fairly crudely fabricated trailing arm to be used where such an arm is manufactured from bent tubing, the strength of which is consequently reduced.

Outline of the Invention It is an object of this invention to provide a vehicle suspension means wh ich is readily attachable to a vehicle and is superior in strength to previous such suspensions and minimises the suspension problems previously described.

The invention is a vehicle suspension system which includes an integral support chassis and suspension means, the suspension means being positioned between extension members of trailing arms, said extension members being associated with wheel hubs, and side members of the support chassis, said trailing arms being pivotally connected to the chassis at pivot points on a lateral end thereof.

It is preferred that the trailing arm is of a welded arcuate sharp rather than a bent tubular member.

It is preferred that the trailing arm be a generally U shaped member with flat upper and lower faces separated by curved side members which are welded to the upper and lower faces. It is preferred that the trailing arm be provided with a cross bracing member interior to hinged connection means at terminal ends of the arm which connect to a generally rectangular support chassis for a vehicle.

It is further preferred that suspension means and associated trailing arms are provided adjacent either lateral side of the support chassis. In order that the invention may be more readily understood we shall describe by way of non limiting example a particular embodiment of the invention with reference to the accompanying drawings.

Brief Outline of the Drawing Figures Fig. 1 shows a perspective view of the integrated suspension and chassis assembly of the invention; Fig. 2 shows the perspective view of Figure 1 from below ; Fig. 3 shows an inverted view of a trailing arm of the invention; Fig. 4 shows a cross-sectional schematic view of the suspension of the invention; Description of a Preferred Embodiment of the Invention In one embodiment of the invention an embodiment which is suitable for use with caravans is provided.

As shown in Figures 1 and 2 a single 2000 kg suspension is provided which includes a support chassis 10, which is in effect a frame of angle iron, which is adapted to be bolted or otherwise connected to the main chassis of the vehicle.

This generally rectangular frame has, at each lateral end, an open channel 12 with extension components 15 on either side of each end of the frame which can engage with the vehicle chassis and be fastened thereto by bolt means. Further bolt holes are also provided in the side members of the frame 11 for additional strength although this is strictly not essential.

The inner lateral end of the frame is provided with downwardly directed members 14 to which trailing arms 20 at either side of the underside of the frame 10 may be pivotally connected at pivot points 16.

The trailing arms 20 are generally U shaped and include cross bracing members 25 and are provided adjacent their far ends, opposite the pivotal connections 16, with cup members 30 at some distance interior to their connections to wheel the hub members 40.

These cup members 30 act as a base for a concentric spring and shock absorber mechanism 45 which passes through to a mounting 50 in each lateral side 15 of the frame or support chassis 10. If required the shock absorber can be mounted separately to the spring.

The invention therefore provides a detachable subframe associated with vehicle suspension means which can be connected to the chassis of a vehicle and which can particularly be used for heavy vehicles such as caravans.

Where a tandem version of the invention is used it is envisaged that loads of up to 3200kg could be mounted in this manner. With such an arrangement it is envisaged that a rocker arm could be used to stabilise the tandem wheel suspension.

Clearly the frame and support components of the suspension system would be manufactured from conventional metal materials however the invention is not restricted to any particular type of suspension mechanism and it is envisaged that an air bag type of system could be used or, alternatively any other type of shock absorbing mechanism required.

The invention is unique however in that it provides an integral support chassis mechanism and vehicle suspension mechanism which is removably attachable to a vehicle chassis.

While we have described herein one particular embodiment of the invention it is to be understood that variations and modifications in the features described can still lie within the scope of the invention.