The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 09, 1989
Filed:
Apr. 26, 1988
Charles B Steger, Warren, MI (US);
Kenneth R Meloche, Warren, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
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.