GB1237441A - Gear pump with movable elements having a plurality of sealing forces - Google Patents

Abstract

1,237,441. Gear pumps. CHANDLER EVANS Inc. Aug. 8, 1968 [Aug. 9, 1967], No.38025/68. Heading F1F. A gear pump comprising a pair of intermeshing gears, includes at least one pressure loaded side plate urged into sealing engagement with the lateral faces of the gears and movable pressureloaded peripheral sealing means comprising a pair of pivotal sealing elements, one for each gear, having arcuate sealing faces and acted upon by first and second vectered forces to sealing engage the tips of the gear teeth to isolate the pump discharge chamber from the pump inlet chamber. In one embodiment, Fig. 5, the tooth tips of gears 6, 7 are engaged by the arcuate faces 27, 28 of sealing elements 145, 146 having elongated recesses 151, 152 engaged by projections 153, 154 on a piston 150 loaded by a spring 156 and pump discharge pressure to provide the first vectored forces. Spring-loaded plungers 147, 148, one for each sealing element, which are also loaded by pump discharge pressure provide the second vectorial forces and overcome any tendency of the sealing elements to be forced away from the gears by internal pump pressure. Other described embodiments, included sealing elements which are formed with depending lugs acted upon by transversely disposed springs or spring-loaded plungers, which urge the lugs transversely and pivot the sealing elements to provide the second vectored forces. In another embodiment, the undersides of sealing elements 119, 120, Fig.4, are formed with recesses 138, 139 which co-operate with projections on a piston 123 and to which pump discharge pressure is applied.