Abstract: An air-ride beam-type axle suspension system for tractor-trailers and other heavy-duty wheeled vehicles having a brake chamber of an air brake assembly mounted on the beam, wherein the beam is tapered. Specifically, each beam of the axle suspension system tapers from a narrower width at its end that is pivotally attached to a frame rail of the trailer, to a wider width at its opposite end. The tapered beam provides easier mounting of the suspension system on existing trailer frame rails and incorporation of a reduced-size pivot bushing at the narrower end of the beam, and optimizes the weight of the axle suspension system.

Abstract: A movable subframe or slider for a tractor-trailer includes a pair of elongated spaced-apart parallel main members and at least one generally K-shaped cross member structure which extends between and is attached to the main members. Specifically, the K-shaped cross member structure includes a base member which extends perpendicularly between and is attached to the main members, and further includes a pair of inclined members, each of which extends angularly between and is attached to a respective one of the main members and the base member. Each of the main members is adapted to be slidably mounted on a respective one of a pair of depending parallel rails of a trailer, and a retractable pin mechanism enables selective positioning of the slider along the rails for variable load distribution of cargo contained in the trailer. A hanger depends from each of the main members adjacent to the ends of the base member for supporting an axle/suspension system.

Abstract: A movable subframe for tractor-trailers, commonly referred to as a slider, includes a retractable pin mechanism having improved locking pins for locking the movable subframe in a selected position relative to the tractor-trailer body. The improved pin includes a tapered or truncated conical-shaped portion which nests in a tapered enclosure when the pins are in the fully extended or locked position. When one or more of the pins of the retractable pin mechanism become jammed in the locked position due to slight misalignment between the respective slider and trailer body openings through which each pin extends when in the locked position, a generally uniformly distributed contact surface pressure exists between the truncated conical-shaped portion of the pin and the tapered enclosure. Other parts of the pin are subjected to relatively intense contact point pressures. Such pressures in turn cause shear forces which resist retraction of the jammed pins.