Adjustable coil spring assembly

A vehicle supplementary spring assembly adapted to supplement the spring force provided by a leaf spring of a vehicle, said leaf spring acting between the chassis of the vehicle and an axle of the vehicle, and extending transversely relative to the axle, and said supplementary spring assembly comprising:

• an elongate coil spring which forms an axially extending passage having a wall of helical configuration defined by the inner surface of the coils of the coil spring;
• a first anchoring insert having an outer surface with a complemental helical formation thereon dimensioned to be in threaded engagement with the helical wall of the passage and adapted to be screwed into one end of the coil spring;
• a second anchoring insert having an outer surface with a complemental helical formation thereon dimensioned to be in threaded engagement with the helical wall of the passage and adapted to be screwed into an opposite end of the coil spring;
• a first connector member connected to the first anchoring insert and adapted to connect the supplementary spring assembly to a first reaction point on the vehicle;
• and
• a second connector member connected to the second anchoring insert and adapted to connect the supplementary spring assembly to a second reaction point on the vehicle;
• adjustment means for adjusting the overall length of the supplementary spring assembly and so as to allow for variations in spacing between the first and second reaction points when fitted to different vehicles;
• said supplementary spring assembly being adapted to apply a tensile force between said first and second reaction points, so as to supplement the action of the leaf spring in supporting the vehicle under conditions of increased loading, said tensile force being selectively variable by varying the position of at least one of the anchoring inserts along the length of the passage, said second connector member being adapted to connect the spring assembly to the axle of the vehicle and being configured to align the coil spring so that its longitudinal axis is perpendicular to and passing through the axle, regardless of the degree of flexure of the leaf spring.