| 摘要 |
<p>1,130,459. Tower cranes. RICHIER. 14 June, 1966 [14 June, 1965], No. 26517/66. Heading B8B. The hoisting means 17 of a tower crane is suspended from a crab 12 and is actuated by a lifting cable 8 extending around pulleys 12a, 12b mounted on said crab and pulleys 9, 10, 11 mounted on the jib 3 of the crane. One end of the cable 8 is attached to a winch 7 and the other end passes over pulleys 14a, 14b on an auxiliary arm 5 and is connected to a further hoisting means 16. For operation of either hoisting means the other is first raised and then locked relative to its support whereby on operation of the winch 7 the unlocked hoisting means may be raised or lowered. The auxiliary arm 5 is mounted for independent rotation about the vertical axis on the top of the tower above the jib and is of a length slightly greater than the maximum radial dimensions of the tower whereby the arm may still be fully rotated when the crane is close to a building. Components such as 6 may be raised by the further hoisting means 16 to form an extension of the tower. In an alternative embodiment, not shown, the end of the cable 8, remote from the winch, is attached to the auxiliary arm 5 and the further hoisting means 16 suspended by a cable loop formed between the fixed end and the pulley 14b.</p> |
