Vane pump with axial vane and rotor seals, radial and axial ports and discharge pressure biased vanes.

摘要

A variable vane pump includes a rotatable cam ring 12 having an elliptical camming bore 35 defining a pumping chamber with intake ports 45a,b. A rotor 40 within the cam ring defines vane slots 72 supporting vanes to define vane buckets. The vanes have axially biased end vane seals 90 for reducing inter-bucket leakage. Side plates separated by an annular spacer enclose the pumping chamber and floating discharge pressure biased axial rotor seals 76a,b within a rotor groove 96 reduce radially inward leakage. The vanes are radially outwardly biased by discharge pressure acting on radial pins 38 via an annular groove in the rotor shaft bore. The vanes each have twin tip sealing lips and are pressure balanced by twin radial bores 82. The side plates have radially opposed inlet bores orthogonal to outlet bores, passages for supplying the pressure biased seals and vanes and are coupled by axial screws passing through slots in the cam ring; the screws acting as cam ring rotation stops. Vane reciprocation provides secondary pumping.