DUAL ACTING HYDRAULIC ACTUATOR FOR ACTIVE SUSPENSION SYSTEM

摘要

C-3914 D-8826 DUAL ACTING HYDRAULIC ACTUATOR FOR ACTIVE SUSPENSION SYSTEM Active suspension for vehicles with a dual acting hydraulic actuator providing foreshortened overall length for a given amount of stroke. A conventional suspension unit when designed to give appropriate wheel travel protruded through the hood. The cylinder tube of the actuator of this invention makes use of concentric tubes proportioned to provide the same pressure-force relationship in both directions and to be no larger than the conventional unit. This actuator also incorporates a trapped air volume that is separate from the oil volumes. This air volume can be appropriately sized so that an air-spring is created by the moving piston. The air spring is of approximately the correct load an rate for the vehicle. This removes the requirement for carrying static vehicle load from the hydraulic portion of the device, which reduces power consumption. This eliminates the requirement for a coil spring around the actuator to carry these static loads and provides a "limp-home" capability in the event that the hydraulic system becomes damaged.