| 摘要 |
1,090,614. Automatic control of jet engines. SOCI•T• NATIONALE D'ETUDE ET DE CONSTRUCTION DE MOTEURS D'AVIATION. Nov. 27, 1964 [Nov. 29, 1963], No.48234/64. Heading G3R. [Also in Division F1] A system for automatically controlling a gas turbine in dependence on a particular function of the inlet and outlet pressures of its compressor, is further controlled by the temperature of hot gases downstream of the combustion chamber. In Fig. 3, pressures dependent on the inlet and outlet pressures P 1 , P 2 of the compressor of a turbo-jet engine 32 are applied to a pressure differential device 27 which controls a hydraulic system 30 adjusting the jet nozzle area to maintain the pressure differential constant. The pressure dependent on compressor outlet pressure is obtained after modification by three restriction orifices. One restriction 8 is preset, another 9 is adjustable by engine throttle lever 10, and a third 19 is adjusted by a servo-operated cam 21 in response to nozzle temperature as detected by a thermocouple 23. Adjustment of this third restriction serves to limit temperature or maintain it constant at a value which is adjustable by a potentiometer (not shown) coupled to the throttle lever. This potentiometer is arranged in a temperature-compensating bridge circuit 24 the output of which opposes that of the thermocouple. The resultant output is applied through a chopper amplifier 26 and has a rate component added by a resistance-capacity network. Rate feedback is applied from a tachometer generator (not shown) driven by electric servomotor 22. Resistors in bridge circuit 24 may be short-circuited by relays to permit temporary over-power operation. Alternative arrangements of restrictions for modifying pressure P 2 are described. The engine is provided with a centrifugally operated hydraulic speed governor, excessive hydraulic signals in which cause operation of a delayed switch to render the temperature control system inoperative by centring cam 21. The temperature control system may also be rendered inoperative manually by operation of a switch. Control of fuel to main and after-burner injectors, and propeller pitch control when the engine is incorporated in an aircraft, is also referred to. |
