GB751617A - Pump assembly and means for cooling bearings thereof - Google Patents

Abstract

751.617. Centrifugal pumps; air tubines. BENDIX AVIATION CORPORATION. Jan. 25, 1954 [Feb. 4, 1953], No. 2181/54. Classes 110(1) and 110(3) A portion of the pumped fluid is taken from the pump outlet and passed through each bearing retainer, for cooling purposes, and returned to the pump inlet. The impeller 130 of a centrifugal fuel pump is driven through shaft 92 by a two-stage turbine 14. Driving fluid, which may be derived from the discharge of an engine-driven compressor, passes from an inlet 30 to the turbine by way of a valve 50 which is urged towards its seat 52 by a spring 56. The valve is opened by a piston 74, which is acted on by pressure fluid which is admitted at 70 and passes through a filter 72. The opening of valve 50 is limited by a shim 82 of selected thickness. Fluid is taken from the pump outlet by way of duct 156, pipe 160 and ducts 164 and 154 to the space 152 between the end wall 42 of the valve housing 38 and a cap 106 bolted to the retainer 100 of a bearing 94, and to a passage 150 around the retainer, to cool the bearing. The fluid is returned to the pump inlet 128 by way of duct 166 and pipe 170. Fluid is also conducted through a duct 180 into a passage 176 around a bearing retainer 116 to cool bearings 114 and returned to the pump inlet by way of a duct 182, a pipe 186 and the pipe 170. The retainer 116 has cooling fins 178. Ducts 156 and 180 may be found as orifices to limit the flow of cooling fluid. Leakage of fluid from impeller 130 along shaft 92 to the bearings 114 is prevented by a carbon ring seal 142 and a slinger 146 which discharges to a drain (not shown). Specification 721,289 is referred to.