GB546691A - Improvements in skip hoists - Google Patents

Abstract

546,691. Guided skip hoists. GROSSMITH, G. W., SARGENT, T., and STRACHAN & HENSHAW Ltd. Jan. 14, 1941, No. 520. [Class 78 (iii)] A skip hoist comprises a rail track 1 extending first in a vertical direction or at a steep incline and thereafter at a slight incline along a line of hoppers 2, a skip 4 mounted on a carriage 3 travelling on said track being first raised, then traversed along the line of hoppers, and finally discharged into any pre-selected hopper, the skip being caused to rotate relatively to its carriage 3 to operate a time control switch whereby the carriage is caused to stop, reverse, and return to its filling point. The carriage 3 is hauled along the track by a winch 23 and rope or ropes 14, guard rails 15 being provided to prevent the carriage leaving the track. The skip is pivoted on trunnions 5 on the carriage and is so balanced whether full or empty that a stop 7 on the skip normally abuts a stop 8 on the carriage. As the skip is hauled along the line of hoppers a horn 9 on the skip is adapted to engage a stop 10 over one of the hoppers, if this stop has been raised from an inoperative position to the position shown in Fig. 2, so that the skip is rotated about the trunnions 5 and discharges into the selected hopper. At the same time the forward movement of the carriage 3 is automatically stopped by means of a pulley 16 on the skip ; as the skip rotates this pulley engages a cord or chain 17 and pulls the arm 18 of a reversing limit or time switch 19 to stop the winch 23. After a time interval determined by the switch 19, the carriage 3 runs down the track 1 under the influence of gravity, the start being assisted by the self-righting torque of the skip, due to the horn 9 pressing against the stop 10. The switch 19 is reset by a weighted arm 22. The stops 10 are provided with weighted arms 12 which tend to maintain them in either of their two positions as determined by stops 13, and they may be operated manually or by remote electrical, hydraulic or pneumatic control means.