| 摘要 |
<p>1,219,611. Jib cranes. H. LIEBHERR. 8 March, 1968 [11 March, 1967], No. 11547/68. Addition to 1,218,826. Heading B8B. A mobile crane similar to that disclosed in the parent Specification has, when the mast is being used as a tower, the tip of the main jib connected by a cable of constant length to a strut pivoted on the mast, and the strut connetted to the hook by a further cable of constant length passing round a sheave on the platform. The mast sections are moved relative to one another by a plurality of rams, Figs. 5 to 12 (not shown).</p> |
