| 摘要 |
811,587. Safety devices for friction-driven winches. GENERAL ELECTRIC CO. Ltd. Aug. 9, 1957 [Aug. 9, 1956], No. 24417/56. Class 78 (5). Mine winch drum 1 drives by friction the haulage cable 2. The movement of the drum is transmitted through gear 4, pulley 5 and belt 6, to tachometer 7; the movement of the cable is transmitted through roller 8 and worm 12 to tachometer 13; and the two resultant E.M.F.'s are balanced across relay 14. Predetermined slip of the cable relative to the drum causes said relay to operate, and to thus bring into play a protective device which either signals the driver or stops the winch motor. Additionally, the movement of the cable may be transmitted by selsyn transmitter 16 to selsyn receiver 17 so as to operate tachometer 18, and the E.M.F.'s of tachometers 7 and 18 may be balanced across relay 19, to bring into play a second protective device. Roller 8 also operates depth indicator 15. |
