GB721289A - Turbine and pump assembly - Google Patents

Abstract

721,289. Centrifugal pumps; gas turbine plant. BENDIX AVIATION CORPORATION. Jan. 15, 1952 [Feb. 1, 1951], No. 1180/52. Classes 110 (1) and 110 (3). In a turbine-driven pump unit, wherein the turbine and pump have a common housing, the turbine is rotatably mounted in sup. port members centrally disposed in spaced axial alignment within the housing and defining therewith a conduit connecting the tube with the inlet and the outlet for the motive fluid, and a valve is slidably mounted in one of the support members in axial alignment with the turbine to control the flow of the fluid from the inlet to the conduit. The pump unit shown which may supply fuel to a jet-propulsion engine or the reheat chamber thereof, comprises a centrifugal pump 16 driven by a two-stage turbine 14. Its housing comprises end sections 18, 24 and intermediate sections 20, 22, joined by bolts 26. Nozzle blades 42 are carried by a block 38 which is centrally located within the housing by hollow pins 44. Driving fluid, such as air from the compressor of a jet-propulsion engine, passes to the turbine 14 by way of a conduit 32, valve 46 and an annular passage 34. To open the valve 46, fluid under pressure is supplied through an inlet 82 and a filter 84 to act on a piston 86 which is connected to the valve by a rod 88. The thickness of a shim 102 is selected to adjust the valve opening to the required size. Holes 60 allow driving fluid to enter the valve 46 to balance the external pressure on the valve. The area of contact at 56 between the valve and its seat 50 is slightly less than the area of the end surface 108, so that there is a net force acting to assist the spring 62 when the valve is closed. To cool a bearing 126, fan blading 144 formed on the side of a turbine wheel 110 draws air from the atmosphere through the hollow pins 44, an annular groove 140 and bores 142 formed in a bearing retainer 128, and discharges it into the stream of driving fluid downstream of the nozzle blades 42. Similarly, cooling air for a bearing 134 is drawn by blading 152 through passages 146, groove 148 and bores 150 in a bearing retainer 136 and is discharged to the driving fluid stream in a conduit 137. The passages 146 are formed in radial struts 132 which support a bearing housing 130. A sealing means 164 is assisted by a slinger 166. Specifications 682,358 and 721,273 are referred to.