Improvements in or relating to a detachable counter-motion device for hoisting and/or translation ropes or chains for the movable trolley of a bridge or travelling gantry crane

摘要

1,092,874. Overhead travelling cranes. MAC GREGOR-COMARAIN. March 16, 1965 [March 25, 1964], No. 11112/65. Heading B8B. [Also in Division E2]. A travelling gantry-crane comprises a main frame 1 with a telescopic girder 3 which may be extended in either direction and a movable handling trolley 4 adapted to move continuously on the entire useful length of the girder 3 and of the frame 1. The position of the trolley 4 is governed by a rope 6, a hoisting hook 10 being operated by a hoisting rope 13. The ropes 6, 13 pass over pulley systems respectively including pulleys 7, 8 and 15, 16 arranged in pairs 7, 16 and 8, 15 respectively disposed co-axially in detachable bearings 40 at the end of the frame 1 and the free projecting end of the girder 3, or vice-versa. The pulleys 7, 16 and 8, 15 are transferred automatically between the end of the girder 3 and the associated end of the frame 3 when the end of the girder 3 is moved into or out of the end of the frame 1. An automatic latching system (see Division E1-E2) locks the pulleys 7, 16 and 8, 15 in place at the end of the frame 1 or the girder 3. The latching system comprises pairs of latches 45a, 45b attached respectively to either side of the frame 1 and of the girder 3. Bistable springs 54 hold the latches 45a, 45b in either locking or unlocking position: as shown in Fig. 6 each latch 45a is unlocked with an arm 52a held against a horizontal rod 53a and each latch 45b is locked with a hook 48 engaged in an orifice 49. Retraction of the girder 3 flush with the frame 1 brings control pins 53b into contact with the arms 52a to pivot the latches 45a into locking position. Further retraction of the girder 3 (i.e. to extend the girder 3 at the other end of the frame 1) causes control pins 53a to swing the latches 45b into unlocked position, the bearing 40 being left supported at the end of the frame 1. The bearing 40 is similarly transferred from the frame 1 to the end of the girder 3 when the latter is extended out from the former.