GB281329A - Improvements in and relating to auxiliary control means for prime movers - Google Patents

Abstract

281,329. British Thomson-Houston Co., Ltd., (Assignees of Goodwin, A. M.). Nov. 29, 1926, [Convention date]. Hand and automatic gear.- Relates to remote control gear for starting and stopping prime movers, particularly applicable to hydroelectric generating units. The valve 6 of the turbine 5 driving the generator 26 is controlled by a governor 18, through a link 10, valve 9, servomotor 8, and follow-up linkage 11, 12. The fulcrum 32 of the link 10 is movable and when the plant is at rest is held in the position shown by a lever 31 on a shaft 33 which is turned against the tension of the spring 34 and the governor spring 20 by fluid pressure beneath the piston 37 The shaft 33 carries a wheel 43 having pawls 46 in engagement with a loose wheel 44 in gear with a pinion 50 driven through irreversible, worm gear 48 from a timing-motor 47. To start the plant a switch 54 is closed, energizing an electromagnet 39, and starting the motor 47 whereby the shaft 33 is turned anticlockwise at a speed determined by the motor, until a pin 61 opens a switch 58, when the turbine assumes its running speed but without load. When the load is put in the generator by closing a switch 29, the motor 47 is restarted by a shunt switch 59, whereupon the shaft 33 continues its movement until a switch 57 is opened by a pin 60, when the end of the lever 31 assumes a position in which the governor controls the speed of the turbine under load. On opening the switch 54 to stop the plant the magnet 39 is de-energized and the lever 31 is returned to its initial position by fluid pressure admitted beneath the piston 37. In a modification the lever 10 is operated by a shaft driven in one direction through ratchet-controlled, epicyclic gearing from the) timing-motor and in the other direction by a coiled spring.