GB767149A - Improvements in and relating to control apparatus for electric mine hoists and the like - Google Patents

Abstract

767,149. Hoist control. ENGLISH ELECTRIC CO., Ltd. July 22, 1955 [July 27, 1954], No. 21952/54. Class 78 (5). Control apparatus for a mine hoist of the kind operable at will under two modes of manual or automatic control, includes a manuallyoperated control lever 10 which both controls the hoist under the first mode of control and effects the change-over to the second mode of control. As shown, the winch drum driven by a slip-ring induction motor is controlled by speed lever 10 and brake lever 60, the two levers being pivoted respectively at 12, 12B so that when said levers are moved to positions within their respective gates 11, 61 (Fig. 2), they engage the clutches shown to move bell-cranks 16 or 17, 65 or 66 to operate links 19, 19A or 100, 37, or 80, 101 or 67 in correct sequence to govern cam followers 90, 84 of cam wheels 86, 87, brake engine 70, change-over switches 38 and 98, master direction controller 18, speed reference controller 23 and speed regulator 24. Speed reference controller 23 and speed regulator 24 are operated from handle 10 through said links 37, 19A and change-over device 20. Said device has horizontal lever 20 which can be locked, by the sliding of bars 34, 35 when operated through crank lever 36 by link 37, so as to pivot either at 29 or at 30 when moved by link 19A so as respectively to influence either speed reference controller 23 through link 21, or speed regulator 24 through link 22, quadrant devide 25, link 48, linkage 26 and actuator 27. The system (Fig. 2) is shown under open-loop manual control. Speed lever 10 works in slots 151, 152 ; brake lever 60 works in slot 153. To change to closed-loop manual control brake lever 60 is kept in brakes-on position 158 whilst speed lever 10 is moved to slot 150 into position 156. (An interlock prevents this movement if lever 60 is not in position 158). Under this closed-loop control, lever 10 works in slot 151 and lever 60 works in slot 153. Similarly, the system may be changed to or from semi-automatic or automatic control. Thus, no separate lever is needed to move the system into or from any of these four methods of control and only two manual control levers are used.