GB458350A - - Google Patents

Abstract

458,350. Fluid-pressure servomotorcontrol systems. SIEMENS APPARATE UND MASCHINEN GES., 4, Askanischer Platz, Berlin. June 19, 1936, No. 17155. Convention date, July 1, 1935. [Class 135] In a charging-pressure regulator for supercharged aircraft engines in which a servomotor 19 controlled by a device 7 responsive to the pressure of the air or mixture passing to the engine, actuates a throttle device 6 so as to restore the charging pressure to a predetermined value, the servomotor is subject to the supplementary control of a device 8 responsive only to temperature changes in the charging air or mixture so that the charging pressure is compensated for such changes and overheating of the engine is avoided. The charging pressure is stabilized at a slightly lower or higher value according as the temperature increases or decreases. As shown, an evacuated bellows 7 in the conduit 1 leading from a blower 5 to the engine is coupled by a rod 9 to a double-armed lever 10, one end of which is connected to the control valve 18 of the servomotor and the other of which carries a roller 15. The latter is held resiliently against a suitably shaped cam 14 on a lever 13 connected to a Bourdon tube 11 which responds to the change in volume of the mercury in a bulb 8. A throttle valve 6 in the inlet 4 of the blower is coupled to the servopiston 19 by a linkage 21 ... 24 and may be operated manually at any time by a lever 26. In a modification, the bellows 7 is filled with air or gas and also controls a further servomotor regulating the quantity of fuel delivered by a fuel injection pump.