Abstract: A suspension system which includes at least one beam, a support spring extending between the vehicle frame and the support beam and a lift spring extending between a lift bracket welded to the beam and the vehicle frame. The support spring is precompressed by using a U-bolt and may be adjusted by increasing or decreasing the length of the U-bolt. Additionally, the spring provides a constant effective force throughout the entire path of travel of the tire-wheel assemblies attached to the axle. While the axle force provided by the spring increases, the force operates through a changing lever arm relative to the pivot point to assure that the spring force operating through the lever arm remains substantially constant throughout the path of travel of the suspension system.

Abstract: A vehicle suspension system having a pair of hanger brackets. A first intermediate bracket dependent from a vehicle, a second intermediate bracket a pair of control arms, and a torque rod. One end of each control arm is pivotally mounted on a corresponding hanger bracket. Another end of each control arm, is pivotally attached to an axle seat. The torque arm is pivotally mounted between the first and second intermediate brackets. One end of a stabilizer bar is mounted to each control arm to increase the suspensions roll stability, and resistance to lateral deflection. In one embodiment, the stabilizer bar extends through a hole formed in each control arm, and in other embodiments, flanges extend outwardly from the stabilizer bar adjacent respective control arms for mounting the stabilizer bar to the control arms.

Abstract: A vehicle suspension system having a pair of hanger brackets and a pair of beams. A first end of each beam is attached, via a bushing sleeve to each hanger bracket, and an axle is rigidly attached to the second end of each beam. Each beam is manufactured from a plurality of layers of laminate material which extend circumferentially around the axle and the bushing sleeve. An adhesive layer extends between the bushing sleeve and axle, and the layers of laminate material, for securing the bushing sleeve and axle to the beam. Inasmuch as the laminate material and adhesive have a relatively low modulus of elasticity, these materials flex in response to movement of the axle, thereby assuring that the connection between the laminate beam and the axle remains stable, even as the axle moves in response to forces acting thereon. In another embodiment of the invention, each beam is integrally formed with an air spring piston.

Abstract: A vehicle suspension system having a pair of hanger brackets and a pair of beams. A first end of each beam is pivotally attached to each hanger bracket, and an axle is rigidly attached to the second end of each beam. A tri-functional bushing is positioned at each pivot to provide a horizontal spring rate different from the vertical spring rate. Each beam is formed with a top section and a bottom section which are joined along the longitudinal axis. Both the top section and bottom section are formed with axle recesses complementary related to a portion of the axle. Each axle recess is formed with a trailing edge positioned on either side of a arcuate section of the axle. In one embodiment, a rear plate extends downwardly from the top section adjacent the front of the axle and is welded thereto. In another embodiment, a half sleeve is positioned circumferentially around a front portion of the axle and is complementary related to the axle recesses of the top section and the bottom section.

Abstract: A suspension system for mounting to a vehicle frame includes a pair of stationary hanger brackets each formed with a compression plate and a pair of sidewalls. A movable hanger bracket is pivotally mounted on a pivot pin intermediate the sidewalls of the stationary hanger bracket, and a beam is pivotally mounted to each movable hanger bracket. An axle extends substantially perpendicular to the beams, and is rigidly attached thereto. An elastomeric bushing is positioned intermediate the movable hanger bracket and the stationary hanger bracket with a compression bolt extending therethrough. A nut threadably engages the compression bolt to draw the movable hanger bracket toward the compression plate thereby applying a compressive force to the elastomeric bushing.

Abstract: A tag axle assembly has a frame having a pair of hanger brackets, an upper cross tube and a lower cross tube. A pair of rocker beams having a primary pivot for pivotally mounting the rocker beam to the support frame is mounted to the frame. A suspension air spring extends between the upper cross tube and each rocker beam, and a lift air spring extends between each hanger bracket and the front end of the rocker beam. An axle seat is hingedly mounted to the rear end of each rocker beam. An upper beam having an actuator beam and a lift bar are pivotally mounted to the axle seat and to the support frame. A linear actuator extends between the support frame and the actuator beam. Inflation of the lift air spring causes the rocker beams to rotate about the primary pivots, and expansion of the linear actuator causes the actuator beam and the interconnected lift bar to raise.

Abstract: A vehicle suspension system having a pair of hanger brackets, with one control arm and one torque arm pivotally mounted on one end to each hanger bracket. Each control arm and each torque arm is pivotally attached to one of a pair of axle seats at another end. One end of a stabilizer bar is mounted to a control arm to increase the suspensions roll stability, and resistance to lateral deflection. The pivotal connections on either end of the control arm include a flexible bushing formed with a hole, and a pivot pin extending through the hole. A lift mechanism includes a compression spring acting against a force plate to move a pair of tire-wheel assemblies between ground engaging and non-ground engaging positions through an interconnected lift bar. The lift mechanism will raise the tire-wheel assembly between a non-ground engaging position, a first ground engaging position, and a second ground engaging position for use in roadrailer applications.

Abstract: A lift axle suspension system to be mounted under a vehicle for selectively raising and lowering a tire-wheel assembly into and out of engagement with a road surface which includes a beam mounted to a hanger bracket via a pivot connector. The hanger bracket is rigidly attached to a vehicle frame rail. An air bellows is interposed vertically between one end of the beam and the hanger bracket for lowering the tire-wheel assembly into engagement with the road surface and providing the support therefor. Another air bellows extends horizontally from the hanger bracket, and is pivotally attached to the beam by a pivot plate at its other end. The pivot plate is pivotally mounted to the beam such that expansion of said other air bellows will cause the beam to rotate about the pivot connector raising the beam and attached axle to raise the tire-wheel assembly out of engagement with the road surface.