| 摘要 |
1501601 Hoisting device SVENSKA FLAKTFABRIKEN AB 25 Feb 1976 [8 April 1975] 07470/76 Heading B8H A hoisting device, shown attached to a platform stand having elements 2, 3, 4, 23 and in use for workmen attaching ventilation elements 10 to a roof (not shown), comprises an outer cradle 5 pivotally mounted on tube 3 and pivotally mounting an inner cradle 6 on pivots 14. Hoisting means 8 is carried by the inner cradle 6 and includes a wire 8a attached to a chain 8b passing over a roller 9 with a groove 9a for the wire 8a and with recesses 9b for the chain links. The chain 8b carries a beam 8d from which the ventilation elements 10 may be suspended. As shown a ventilation element 10 has been hoisted up to the inner cradle 6. Continued hauling on the wire 8a causes the inner cradle 6 to pivot to a vertical position 15<SP>1</SP>, shown in broken lines (see arrows 15a, 21a), whereupon further hauling on the wire 8a causes both cradles 5, 6 to pivot jointly about the tube 3 into a position, indicated by broken line 23, parallel with tube 23. Upon continued hauling on the wire 8a the ventilation element 10 passes from the cradles 5, 6 to rest on the tube 23. The cradles 5, 6 then pivot back under their own weight into their initial position. |
