Patent GB-635967-A (GB)
Title: Improvements relating to regulators for internal combustion engines
IPC: F02D9/00
Filed: 1945-11-28
Abstract: 635,967. Fluid - pressure servomotor control systems. BENDIX AVIATION CORPORATION. Nov. 28, 1945, No. 32198. Convention date, Dec. 11, 1944. [Class 135] [Also in Group XXVII] In a supercharged aircraft engine of the kind in which a boost control maintains the pressure in the engine induction passage at either of two predetermined values, in response to changes of pressure in a conduit connected to the induction passage, and having a leak controlled by a valve which is opened or closed in dependence upon the operation or non-operation of an anti-detonant fluid injection system, the conduit leading from the induction passage to the leak is provided with two restricted orifices and the boost control is connected to the part of the conduit between these orifices. A throttle valve 7, Fig. 1, in the inlet to the supercharger 1 is controlled, in accordance with the supercharger outlet pressure by a boost control 12 comprising a sealed bellows 13 and a bellows 14 connected by a conduit 20 containing a restriction 26 to the supercharger outlet 3. The conduit 20 also connects, through a restriction 27, with a chamber 21 housing a spring-loaded valve 30 controlling communication of the conduit 20 with a conduit 29 connected to the supercharger inlet. A stem 31 of the valve 30 extends into a chamber 35, vented at 45 and bounded on one side by a diaphragm 36 subjected on its upper surface to the pressure of the anti-detonant fluid communicated through a conduit 46. Thus, when the anti-detonant system is in operation, the diaphragm 36 is depressed to open the valve 30, thereby reducing the pressure in the bellows 14 and causing the boost pressure to be increased. In a modification, Fig. 2, the leak opens to atmosphere and means is provided to prevent the pressure drop occasioned by opening of the leak from increasing with increase in altitude. A first stage supercharger 51, driven by an exhaustgas turbine, delivers air past a pilot-controlled throttle-valve 58, through a carburetter 56, to an engine-driven second-stage supercharger 65. The exhaust-gas turbine is controlled by a waste gate-valve 75 adjusted by a regulator or boost control 78 subjected to the supercharger interstage pressure through a conduit 80, a restriction 91 and passages 90A, 90B, 79. The setting of the regulator 78 is adjusted manually by an arm 85. A valve 140, spring-biassed to its closed position and opened by a diaphragm 118 subjected to the pressures before and after the restriction 91 through passages 95, 176 respectively, controls communication of the passage 90A with a chamber 160 which chamber communicates, under the control of a valve 115, with the atmosphere through a passage 170. The valve 115 is actuated by a spring-loaded diaphragm 101 subjected on its lower surface to the pressure in the conduit 80, and on its upper surface, to the pressure in a conduit 105 connecting with the anti-detonant system, whereby, when this system is in operation the valve 115 is opened, placing the chamber 160 and therefore the passage 90A in communication with the atmosphere and changing, the datum of the regulator 78. As the altitude increases, the pressure in the passage 170, in the chamber 160, and the passages 90A, 90B, 176, falls and the diaphragm 118 moves downwardly to decrease the opening of the valve 140 and maintain substantially constant the pressure difference between the conduit 80 and the passages 90A, 90B, 79. Specification 611,909 is referred to.