GB542830A - Improvements in and relating to lubricating systems - Google Patents

Abstract

542,830. Fluid-pressure servomotor control systems. BRITISH THOMSON-HOUSTON CO., Ltd. (General Electric Co.). April 10, 1941, No. 4769. [Class 135] [Also in Groups XXXIV and XXVI] An exhaust-gas turbine-driven supercharger has a lubricating system for the shaft bearings in which a scavenging pump 51 which forces oil from the sump 50 to the tank 39 has a greater capacity than the feed pump 36 which forces oil from the tank 39 to the bearings, both pumps being driven from the shaft 15. Oil from the feed pump passes through conduits 41, 42 to the bearings 16, 17 and thence to pockets 32 ... 35. Pockets 34, 35 lead to annular pockets 54, 55 which with pockets 32, 33 drain to the sump 50. The discharge pressure of feed pump 36 is in excess of that required for lubrication and a relief valve 45 in the outlet 26 connects to byepass 46 and inlet 37. The outlet 26 also connects to a chamber 27 in a servomotor 22 with piston 23 actuating the control valve 21 of the turbine 18 which drives the shaft 15 and the impeller 14. The outlet scroll 12 is connected to chamber 30a which has a bellows 30 coupled to a valve 28 connecting outlet 26 and chamber 27 to discharge 29. A drop in the pressure of the air discharge causes an expansion of bellows 30 to close valve 28 so that pressure in chamber 27 increases and valve 21 is opened to increase the flow of gas to the turbine. The casing 59 for bearing 17 has grooves 60, 61 connected to the scroll 12 to prevent leakage of oil along the shaft 15 from pockets 34, 35. Pockets 32, 33 may connect into chamber 64 surrounding the gearing 63 for pumps 36, 51.