GB444174A - - Google Patents

Abstract

444,174. Fluid pressure servomotor systems. AKT.-GES. BROWN, BOVERI, & CIE, Baden, Switzerland. July 13, 1934, No. 20574. Convention date, July 13, 1933. [Class 135] In a steam generator fired with air and oil under pressure and in which the air is supplied by a compressor driven by a gas turbine assisted by an auxiliary motor, the power of the auxiliary motor is controlled by the steam consumption, the power of the prime mover or the quantity of fuel used by the furnace. As shown in Fig. 1, the flow of steam from the boiler 1 to the turbine 7 driving a generator 8 acts upon a diaphragm 10 to control a valve 11 in a pressure oil pipe 12 to vary the pressure acting upon a piston 13 connected to the fuel injection valve 6. Variation of the oil pressure in the pipe 12 is also transmitted to a device 15 by which the brushes in the case of an auxiliary alternating current motor 4 or a resistance in the case of a continuous current motor may be displaced to vary the power of the auxiliary motor assisting the gas turbine 3 driving the compressor 2 supplying combustion air. The oil pressure in the pipe 12 may also be regulated by the output of the generator 8 through the electric regulator 26 connected to the valve 27. Fig. 2 shows an alternative form of control in which steam pressure in the pipe 17 controls through the diaphragm 19 the pressure oil supply to the piston 13 to regulate the fuel supply valve 6, the oil supply to which passes over both sides of an apertured diaphragm 21, the pressure difference on which is balanced by the pressure difference on a diaphragm 23 connected to the air supply pipe constriction nozzle 24 when the fuel and air supply are in the current ratio. Variation of the oil supply operates the valve 25 in the pressure oil supply pipe and actuates the regulator of the auxiliary motor 4. Specification 424,604, [Group XII], is referred to.