| 摘要 |
<p>The telescopic beam is made up of a base section, hinged to the crane mounting vehicle and several telescopic sections. A multiple pressure cylinder has a piston hinged to the base section, and there are telescopic cylinder sections for each telescopic section with synchronising cables, or chains, for synchronous extension and retraction. The multiple pressure cylinder (7) carries a plunger, and the synchronising cables (12-14) are fitted to driven cable drums (15-18) whose different circumferential speeds are matched to the separate extension and retraction ratios.</p> |
