GB1235013A - Improvements in rotary pumps and motors - Google Patents

Abstract

1,235,013. Rotary pumps and motors. SPERRY RAND CORP. Nov.10, 1969 [Nov.14, 1968], No.54863/69. Heading F1F. In a rotary sliding vane pump (or motor), as shown of the multi-abutment type, to reduce wear and friction between the end faces of the rotor 52, Fig.1, and the adjacent end-face48 of a housing and cover 20 and end-face 50 of a wear plate 18 the axial length of the rotor 52 is slightly less than the axial width of cam ring 14 to permit slight axial floating movement of the rotor. Annular grooves or pressure pockets 98, 100 provided in the end-faces 48, 50 respectively communicate through substantially constant area restricted passageways with the high-pressure side of the pumps (or motor) and through variable area restricted passageways with the low-pressure side of the pump (or motor). Pressure fluid is admitted to the pocket 98 from high-pressure passage 30 via ducts 90, Fig. 4 (not shown) annular groove 86 and V-shaped grooves 106, 108 and to the pocket 100 from the annular groove 86 via undervane pressure chambers 84, annular groove 88 and V-shaped grooves 110, 112, Fig.3. Pressure fluid seeps from the pockets 98, 100 past lands 102, 104 in the end-faces 48, 50 respectively. The land 102 seperating the pocket 98 from a recess 94 at the shaft end and the land 104 separating the pocket 100 from the shaft bore which is connected to low-pressure via a duct 97. On a build up of pressure between one of the lands and the associated end-face of the rotor, the rotor moves towards the other land until the clearances on the two sides of rotor are equal and the rotor is in pressure balance. The clearances are such to produce liquid films between the rotor and the end-faces to provide lubrication.