GB834609A - Control apparatus for superchargers for internal combustion engines - Google Patents

Abstract

834,609. Charge pumps. GARRETT CORPORATION. Nov. 5, 1957 [Nov. 6, 1956], No. 34494/57. Class 7(2) [Also in Group XXIX] An exhaust by-pass 23 of an exhaust driven turbo-supercharger 16, 17, is controlled by the compressor inlet and outlet pressures to maintain a constant pressure ratio across the compressor 17. The bypass 23 is controlled by a poppet valve 27, Fig. 2, connected to a spring-loaded piston 36 which is adjusted by a fluid pressure set up in chamber 35 by an engine driven lubricating pump 13 and controlled by a bleed valve 51, Fig. 4, actuated by a diaphragm 60 which is subjected to the compressor inlet and outlet pressures conducted through lines 65, 66, to the chambers 62, 61. The chamber 35 is connected to the pump 13 by a pipe 40 and to the space above valve 51 by a pipe 42, the fluid escaping through valve 51 being returned to reservoir 64. The effective area of the upper surface of diaphragm 60 is reduced by a bellows 68 connected to an adjustable stud 70 to produce the desired pressure ratio across the compressor 17, the diaphragm 60 holding the valve 51 open at stable coriditions a sufficient amount to set up a pressure in chamber 35 which holds the by-pass valve 27 open an amount which maintains the turbine 16 and compressor 17 at a speed which produces the desired pressure ratio. A second diaphragm 58 connected to the diaphragm 60 and normally subjected to compressor inlet pressure on both sides moves the valve 51 wide open to put the compressor out of operation if the diaphragm 60 ruptures.