| 摘要 |
A positive displacement pump for a vehicle power steering system comprising a rotor (42) rotatable in and cooperating with a stator (20) to define a pump cavity (52), (54), inlet and outlet ports (56), (58) and (34), (36) communicating with the pump cavity and a flow control valve (96) located in the flow delivery circuit wherein provision is made for opening the flow delivery ciruit to a bypass circuit (72) upon an increase in the speed of the vehicle beyond a design point thereby reducing the pump back pressure and power usage which results in incrased "road feel" at increased speeds while maintaining normal power assist during steering maneuvers at low speeds. |
