VARIABLE DISPLACEMENT PUMP WITH MULTIPLE PRESSURE CHAMBERS

摘要

A variable displacement vane pump has a plurality of seals between the inner surface defining the housing's internal chamber and an outer surface of the control ring. The seals define a plurality of pressure regulating chambers comprising a first chamber and a second chamber each for receiving pressurized fluid. The first chamber is defined between a pair of seals located in a circumferential direction of the ring on opposing sides of the pivotal mounting of the control ring and having at least one inlet for receiving pressurized fluid. The circumferential extent of the first chamber is greater along a portion for applying force to the ring in a second pivotal direction than along a portion for applying force in the first pivotal direction such that a net force is applied in the second pivotal direction. The second chamber is defined between a pair of seals located in the circumferential direction of the ring and has at least one outlet for receiving pressurized fluid such that the entire circumferential extent of the second chamber applies force to the ring in the second pivotal direction.

主权项

1. A variable displacement vane pump comprising:
a housing comprising an inner surface defining an internal chamber, at least one inlet port and at least one outlet port; a control ring pivotally mounted within the internal chamber, the control ring having an inner surface defining a rotor receiving space; a rotor rotatably mounted within the rotor receiving chamber space of the control ring, wherein the rotor has a central axis eccentric to a central axis of the rotor receiving space; the rotor comprising a plurality of radially extending vanes mounted to the rotor for radial movement and sealingly engaged with the inner surface of the control ring such that rotating the rotor draws fluid in through the at least one inlet port by negative intake pressure and outputs the fluid out through the at least one outlet port by positive discharge pressure; a resilient structure urging said control ring in a first pivotal direction; a plurality of seals between the inner surface defining the housing's internal chamber and an outer surface of the control ring, the seals defining a plurality of pressure regulating chambers comprising a first chamber and a second chamber each for receiving pressurized fluid; wherein the first chamber is defined between a pair of seals located in a circumferential direction of the ring on opposing sides of the pivotal mounting of the control ring and having at least one inlet for receiving pressurized fluid, the circumferential extent of the first chamber being greater along a portion for applying force to the ring in a second pivotal direction than along a portion for applying force in the first pivotal direction such that a net effect is an application of force in the second pivotal direction; and wherein the second chamber is defined between a pair of seals located in the circumferential direction of the ring and has at least one inlet for receiving pressurized fluid such that the entire circumferential extent of the second chamber applies force to the ring in the second pivotal direction.