Patent ID: 7226105

Claim:
A hydraulic vehicle seat adjustment system for providing powered adjustment of the position of a seat or seat portion, the system comprising arranged in a hydraulic circuit: a pump for generating a flow of pressurised hydraulic fluid; a flow controller for controlling and directing the flow of pressurised hydraulic fluid; and a hydraulic actuator comprising a first inlet/outlet and a second inlet/outlet, the actuator adapted to move the seat portion in response to a flow of pressurised hydraulic fluid directed to and from the first inlet/outlet and second inlet/outlet by the flow controller; wherein the actuator comprises a first system protection valve for the first inlet/outlet of the actuator and second system protection valve for the second inlet/outlet of the actuator; the first and second system protection valves are adapted to be activated in response to pressure within the actuator exceeding a predetermined threshold level, and when activated are adapted to at least partially close off the respective inlet/outlet to hydraulically isolate the actuator and hydraulic fluid within the actuator from the remainder of the hydraulic circuit and adjustment system.