Abstract: A trailing arm axle/suspension system includes rigid or spring beams for mounting the axle directly to the beam without any or minimal, respectively, additional mounting hardware or structure. An axle mounting plate is formed as part of the preassembled rigid beam or attached to the spring beam, and is formed with a recess that can range from significantly smaller than to generally the same size as the smallest axle which will be seated therein. The axle is extruded into the recess to eliminate clearance and create intimate contact between the axle and the axle mounting plate. The force typically deforms the axle from its normal cross-sectional shape, such as round, into a generally oval or elliptical cross-sectional shape. Such clearance-free intimate contact also creates a constant preload or compression between the axle and the axle mounting plate in the recess area.

Abstract: An air-free, relatively lightweight lift assembly for an axle/suspension system of a highway/rail convertible semi-trailer, utilizes a transversely-oriented coil torsion spring having a relatively low spring rate. The torsion spring is captured between a stationary plate and a rotatable plate. A flexible link is pivotally attached at its upper end to the rotatable plate and at its lower end to the axle. This assembly results in a variable rate moment arm and continuously increasing leverage when the suspension air spring is overinflated to lower the system for transfer of the trailer from a highway tractor to a rail bogie, thus enabling use of a less robust air spring. The assembly conversely creates a decrease in leverage at the lifted rail transport position, to securely maintain the axle/suspension system in the rail position. For highway use, the lift assembly provides suspension damping without shock absorbers.

Abstract: An automatic pneumatic control system for the air springs of a semi-trailer air-ride trailing beam-type axle/suspension system. A plurality of conduits and valves of the control system pneumatically interconnect one or more sources of compressed air, the vehicle parking brakes and the suspension air springs. The control system incorporates a vented two-position two-way pilot valve for controlling inflation and deflation of each air spring. The valve closes when air pressures in a pair of control system sensor lines differ, thereby enabling complete or nearly complete deflation of the air spring it controls before the parking brake is set, thereby minimizing or eliminating the problems of trailer drop and walk during loading of an empty trailer, heretofore caused by complete or nearly complete deflation of the air springs only after the parking brakes are already set.

Abstract: A trailing arm axle/suspension system includes rigid or spring beams for mounting the axle directly to the beam without any or minimal, respectively, additional mounting hardware or structure. An axle mounting plate is formed as part of the preassembled rigid beam or attached to the spring beam, and is formed with a recess that can range from significantly smaller than to generally the same size as the smallest axle which will be seated therein. The axle is extruded into the recess to eliminate clearance and create intimate contact between the axle and the axle mounting plate. The force typically deforms the axle from its normal cross-sectional shape, such as round, into a generally oval or elliptical cross-sectional shape. Such clearance-free intimate contact also creates a constant preload or compression between the axle and the axle mounting plate in the recess area.