GB766718A - Improvements in or relating to ships' derricks - Google Patents

Abstract

766,718. Jib cranes. DIETLEIN, H. W. A. VON., [trading as STULCKEN SOHN KOMM.- GES., H. C.]. Aug. 26, 1954 [Feb. 11, 1954; April 5, 1954J, No. 24885/54. Class 78 (4). Independently-winched hangers 53, supporting a boom 5 from a pair of masts 3 are so guided that the boom may be swung through the masts from one side to the other and the load tackle 43, 44 is arranged so that it may be swung from one side of the boom 5 to the other without unreeving. As illustrated, the blocks 58 on the boom for the hanger tackle are carried on sleeves each of which rotates about one limb 40 of a fork at the end of the jib while the blocks 56 adjacent the masts 3 are carried by rotating heads 14 on the masts. The hauling ends 52 of the hanger tackles pass into the hollow interiors of the heads 14 over pulleys 46 and down through the hollow masts to pass over pulleys 47, 48 which guide them out of slots 54 to pass to the hanger winches. The hauling ends 43 of the load tackles similarly pass from pulleys 42 carried by the rotatable sleeves 41 on the fork ends of the jib into the interior of the heads 14 of the masts and over pulleys 45, 49, 50 to pass out of slots 51 in the masts to the load winches. When the boom is to be moved from one side of the mast to the other the lower block 63 is drawn up to the upper block 62 so that interengaging surfaces 64, 61 on the blocks connect them, to swing over a bolt 59 from which the upper block 62 is suspended. As the blocks pass through the fork 40 the hauling ends 43 of the load tackle are guided by pulleys 66, 67 carried on discs 65 free to rotate on either side of the lower block.