Patent attributes
A variable displacement engine oil vane pump includes a displacement control for controlling displacement of the pump. The control includes a cam ring in a housing pivotally connected to a wall of the housing by a pivot. The cam ring is internally engaged by slide vanes. A control chamber is defined by the cam ring and the housing wall. A control orifice provides for communication of control oil from a pressurized source to the control chamber. A vent chamber is generally opposite the control chamber and is defined by the cam ring and the housing wall. A dump chamber is defined by the cam ring and the housing wall and is generally disposed between the control chamber and the vent chamber. A dump orifice provides for communication between the control chamber and the dump chamber. A vent orifice provides for communication between the vent chamber and the dump chamber.
