Patent ID: 7618247

Claim:
A fluid pressure energy translating device of a sliding vane type comprising: a cam ring including an internal contour, a rotor having a plurality of vanes notable therewith and slideable thereto in slots in rotor with one end of each said vane engaging said internal contour, each said vane has an undervane chamber which is subject to discharge to urge engagement contact with said internal contour, an axial passage in said rotor is located between each pair of vane slots and providing an axial port on each side of said rotor, a radial port is located on the peripheral surface of said rotor and between each pair of said vane slots inward to intersect with said axial passage, said rotor and said cam ring with said internal contour configuration to define one or more pumping cycles between the said periphery of said rotor and said internal contour by which said vanes carry fluid from the inlet port to the outlet port, each said pumping cycle consists of an inlet zone, an inlet to discharge (precompression) transition zone, a discharge zone, and a discharge to inlet (decompression) transition zone, axial support surfaces are provided to retain and guide the rotating group consisting of said rotor and said vanes, said axial support surfaces contain valve timings to define said pumping cycle with respect to said internal contour, each said valve timing contains strategically located access ports to radially correspond to said axial ports in said rotor, said access port is strategically located in the inlet to discharge (precompression) zone, another said access port is strategically located in the discharge zone, both said access ports are located to angularly correspond to two (2) consecutive said axial ports in said rotor, both said access ports are connected by a passage located beneath the surface of each said axial support surface, the angular location of both access ports control the registered opening with said axial ports in said rotor when the intervane volume has completed the filling cycle and is sealed from said inlet port, and the registered opening between said axial ports in said rotor and said access ports complete the circuit for directing pressurized flow through several restrictions and into said intervane volume in said precompression zone.