Patent ID: 7487856

Claim:
A hydraulic power steering system for a motorized vehicle comprising: a hydraulic pump for generating hydraulic pressure; a hydraulic cylinder system having a first chamber of variable volume, a second chamber of variable volume, and at least one movable piston; a steering mechanism operatively engaged with the at least one piston of the hydraulic cylinder; a hydraulic fluid reservoir; and a control valve arrangement operable to selectively connect the first and second chambers of the hydraulic cylinder to the pump and the reservoir, the control valve arrangement operable in at least a first condition, a second condition, and a third condition; wherein in the first condition the control valve arrangement connects the first chamber with the pump and connects the second chamber with the reservoir for fluid communication therebetween; in the second condition the control valve arrangement connects the first chamber with the reservoir and connects the second chamber with the pump for fluid communication therebetween; and in the third condition the control valve arrangement connects the first and second chambers with each other and disconnects the first and second chambers from the reservoir.