GB1168185A - Improvements in and relating to Hoisting Systems - Google Patents

Abstract

1,168,185. Hoisting systems. FREDRIKSSTAD MEK VERKSTAD A.S. 28 May, 1968, No. 25464/68. Heading B8B. A system for hoisting a group of load platforms 1, 2, 3, 4 from a working position in which they are suspended and spaced one above another, to a stowed position in which they are stacked together, comprises a hoisting cable 10 for lifting the bottom platform 1 and hence the platforms thereabove and cables 20, 22, 30, 32 for balancing the bottom platform generally parallel to the other platforms. In the working position the platforms are intersupported by links 6, 8 and rest on brackets 9 on a side wall. The hoisting cable 10 extending from a winch 12 passes over pulleys Q<SP>1</SP>, T, X, U, on an overhead support 14 and around pulleys G, H, S, W, K, J on the lower platform 1, the end of the cable 10 being secured at L to the platform 1. The bottom platform 1 is balanced transversely and longitudinally by pairs of cables 22, 20 and 30, 32 respectively, all of which are anchored above and below the group of platforms, and engage pulleys on the bottom platform. In operation the platform 1 is hoisted and thereafter lifts the other platforms until rollers 50, 52 on the top platform 4 engage abutments whereupon the stack of platforms rotate about the axis of the rollers into an inclined stowed position. In the embodiment of Fig. 5 (not shown), the transverse and longitudinal balancing of the bottom platform is effected by a pair of cables which run diagonally opposed to each other over the bottom platform. In a further embodiment, two hoisting systems are used, one for hoisting the lower platforms and one for the upper platforms. In other embodiments, the number of points at which the hoisting cable supports the latter platform is varied.