Improvements in or relating to lifting, pulling and pushing mechanism

摘要

732,721. Ratchet chain hoists; ratchet gears operated by levers. SMITH, G. S. Aug. 28, 1953 [Sept. 13, 1952], No. 23062/52. Classes 78 (3) and 78 (5). The apparatus described in Specification 582,998 is modified by making the friction discs 4, 5, 6 freely rotatable relative to the casing 1 and shaft 2, and by providing a single start thread 2a. The discs 5, 6 are of fibre and are mounted on bosses formed respectively on the metallic disc 4 and the clutch member 3. According to a modification (not shown) the discs 5, 6 are both mounted on the disc 4 by means of bosses one extending from each side thereof.