GB1002758A - Anti-pendulation device for jig cranes - Google Patents

Abstract

1,002,758. Preventing the load of jib-cranes from swinging. C. H. WHEELER MANUFACTURING CO. Nov. 20, 1962, No. 43909/62. Heading B8B. The load of a jib-crane is prevented from swinging by lines 18, 19, Fig. 2, which are wound on to drums 16, 17 at the same rate that a hoisting line 13 is wound on to a drum 12. All the drums are driven by a single motor through a shaft and differentials 28, 29. In addition, the drums 16, 17 may also be driven by motors 30, 31 which have electric brakes 30a, 31a. Pulleys 22, 23 may be mounted directly on the jib 4, Fig. 3, instead of on an arm 24, Fig. 2. In a further embodiment the drums 16, 17 and their motors 30, 31, Fig. 6, are mounted on top of the king-post of the crane, the drive from the drum 12 to drums 16, 17 being through a pulley 14 and a shaft and differentials 28, 29. The operator, who sits in a chair 32, Fig. 4, controls the motors 30, 31 to wind in either of the lines 18, 19 faster than the hoisting line according to which way the load is tending to swing, by depressing foot pedals 33, 34. Pushbuttons 37, 38 control the motors when line is paid out. Level luffing is effected by leading the hoist rope 13, Fig. 1, over a pulley 14 on top of the king-post. The king-post and jib are slewed by ring gear 7.