Patent ID: 6817175
Filing Date: 2004-11-16
Classification: B62D,B64C,F15B

Abstract:
A hydraulic steering system architecture comprising at least one steering control actuator having chambers connected to the outlets of a directional-control valve which presents a feed port and a return port, wherein the hydraulic system comprises an accumulator and an electrically-driven pump unit associated with an emergency supply which is arranged to maintain a predetermined pressure level in the accumulator, and wherein the hydraulic system comprises a general selector arranged, in a normal mode of operation, to connect the feed port of the directional-control valve to a pressure-generator device and the return port of the directional-control valve to a main supply associated with the pressure-generator device, while also ensuring that the emergency supply is filled, and in an alternate mode of operation, to connect the feed port of the directional-control valve to the accumulator.