GB1358051A - Hydraulic gear pump - Google Patents

Abstract

1358051 Rotary gear pumps and motors MASCHINENFABRIK FRIEDRICH REICHERT GmbH 15 Sept 1971 [16 Sept 1970 6 March 1971] 43032/71 Heading F1F An internally meshing hydraulic gear pump comprises a housing 1, 2 supporting, via bearings 5, a shaft 4 on which is mounted a pinion 3 meshing with a transversely movable gear ring 14, loaded against the pinion 3 and a filler-piece 10 on the high pressure side by high pressure fluid supplied to a space 9 and acting on the ring 14 through an arcuate arm 7 pivoted at 8, axial sealing of the working space being effected by pressure-loaded check plates 15. The space 9 is supplied with pressure fluid via a passageway 13 which passes through the pivot 8 which may be formed integrally with the arm 7, and may also be hemispherical. Pressure fluid is also supplied via passage 32 and recess 27 to the contacting surfaces of the arm 7 and ring 15 to provide lubrication, Fig.6. The bearings 5 are lubricated by fluid from the high pressure side leaking along the shaft 4, being sealed from the low pressure side by seals 22, the fluid being returned to the low pressure side on reaching the end of the shaft 4 via pre-loaded check valves which thus maintain the bearings filled with fluid. To compensate for minor alignment errors, the arm 7 may be provided with a groove 26 in each axial side face, and the filler piece 10 may have recesses on its side faces to relieve axial pressure thereon by the cheek plates 15 in the event of wear of the gears, a narrow lip surrounding these recesses allowing leakage of high pressure fluid into the tooth spaces coming from the low pressure chamber hence reducing noise.