GB191202657A - Improvements in Apparatus for Preventing Overwinding at Collieries, Mines or other Places. - Google Patents

Abstract

2657. Ashton, W. H. Feb. 1. [Cognate Application, 12,484/12.] Overwinding, preventing; emergency power cut-off year.-Relates to apparatus for preventing overwinding at collieries &c., in which a slowly-rotating stop member engages towards the end of the wind with a treadle connected to stop-gear, and consists primarily in moving the stop member nearer to the treadle by means of a governor when the speed is excessive. A nut travelling along a screw driven by the engine engages towards the end of the wind with one or other of a pair of tappets secured to a rack. A pinion 15 gearing into the rack is attached to a rock-shaft 12, which carries stop members or arms 13, 14 projecting in opposite directions and adapted when rocked downwards to engage treadles 23 adjustably mounted on levers 19, 20. A catch 3 coupled by links 21, 22 to the lower arms of the levers 19, 20 is thereby raised and releases a spring-controlled bar 1, which closes the throttle and releases a spring-actuated brake lever 34. The arms 13, 14 and the treadles 23 are pivoted so as to give during their backward or idle stroke. In order that the engine may be shut off earlier if the speed is high, the sleeve of a governor 30 is, by means of a lever 29, arranged to give an axial movement to the shaft 12. The arms 13, 14 are attached to sleeves 27 which are secured to the shaft 12 by pins entering helical grooves 26, so that, as the shaft is moved endways, the arms 13, 14 are brought closer to the treadles 23. An auxiliary pair of tappets 40 are arranged to prevent the cage from passing beyond the proper stopping-place. The governor lever 29 may be arranged to operate a trip gear for stopping the engine if the speed should be excessive at any period of the wind.