US 5,924,712 A · Dual trailing arm vehicle suspension

Abstract

A suspension system for a vehicle includes a longitudinally extending frame, an axle connected to the frame for relative movement with respect thereto, an air spring mounted between the frame and the axle to yieldably support the axle with respect to the frame, and upper and lower trailing arms attached to each side of the frame. A first torsion bar extends between and is rigidly attached to the upper trailing arms and a second torsion bar extends between and is rigidly attached to the lower trailing arms. The torsion bar cooperates with the springs during deflection of the suspension system with respect to the frame to thereby yieldably resist relative movement between the trailing arms and the frame. In one embodiment, the upper and lower trailing arms are parallel to each other. This arrangement results in load equalization between the suspension assemblies. Any relative torque caused by deflection of the trailing arms is equally distributed between both torque bars. In another embodiment, the upper and lower trailing arms are non-parallel, and arranged such that when the trailing arms pivot due to road conditions or vehicle loading, fore and aft movement of the air spring and axle due to arcuate swing of the trailing arms is minimized.

Claims16

Dependent claims

In a suspension system for a vehicle having a frame with a pair of opposite sides, the suspension system including a pair of frame brackets laterally spaced from each other and each of which is adapted to be mounted to a side of the frame;

a first pair of longitudinally extending upper trailing arms having first ends pivotally connected to the frame brackets and second ends;
a second pair of longitudinally extending lower trailing arms having first ends pivotally connected to the frame brackets and second ends, the upper trailing arms being vertically spaced above the lower trailing arms;
an axle pivotally mounted to and extending between the second ends of each set of first and second trailing arms, the axle having opposite ends and a central axis, a pair of springs mounted to the second ends of the first and second trailing arms and adapted to be mounted to the vehicle frame to cushion the movement of the first and second trailing arms toward the vehicle frame;
a first torsion bar extending between and being rigidly attached to one of the pairs of upper and lower trailing arms, the torsion bar being adapted to yieldably resist relative rotational movement between the one pair of trailing arms and the frame;
the improvement which comprises:
the second ends of the first trailing arms are mounted to the axle vertically above the axle and the second ends of the second trailing arms are mounted to the axle vertically below the axle, and the pivotal mounting of the second ends of the first and second trailing arms to the axle and the central axis of the axle are aligned.

3 more elements

a first pair of longitudinally extending upper trailing arms having first ends pivotally connected to the frame brackets and second ends;
a second pair of longitudinally extending lower trailing arms having first ends pivotally connected to the frame brackets and second ends, the upper trailing arms being vertically spaced above the lower trailing arms;
an axle pivotally mounted to and extending between the second ends of each set of first and second trailing arms, the axle having opposite ends and a central axis, a pair of springs mounted to the second ends of the first and second trailing arms and adapted to be mounted to the vehicle frame to cushion the movement of the first and second trailing arms toward the vehicle frame, a first torsion bar extending between and being rigidly attached to one of the pairs of upper and lower trailing arms, the torsion bar being adapted to yieldably resist relative rotational movement between the one pair of trailing arms;
and the improvement comprising:
the upper trailing arms are in a common plane with the lower trailing arms.

2 more elements

Dependencies are inferred from the claim text.

Dual trailing arm vehicle suspension

Life of this patent

Dual trailing arm vehicle suspension

Life of this patent

Abstract

Claims16