Vehicle suspension with load-controlled damping and load-controlled

Abstract

A vehicle suspension system with load-controlled damping for a vehicle having a leveling valve actuated by changes in the distance between the axles and the frame and connected to air springs and to a damper to provide load control of the damper. The damper has two cylinders, an inner one filled with oil and in which a piston moves, and an outer one with an annular space between them mostly filled with oil. A jounce metering valve passes oil from below the piston into the annular space upon downward movement of the piston, the resistance to the fluid flow being varied by pressure applied by the leveling valve in accordance with vehicle load. A high-speed-jounce blow-off valve passes oil in the same manner in larger amount when actuated by high-velocity downward movement of the piston, the actuation speed depending on the pressure applied by the leveling valve. Similarly a rebound metering valve sends oil through the piston upon its upward movement, and there is a high-speed-rebound blow-off valve for sending additional oil therethrough, and the resistance of the pressure and the actuation velocity of the latter depend on the pressure applied by the leveling valve, which depends on the frame-supported load.