| 摘要 |
<p>A pendant control system for pendant supported multi-section telescopic boom is disclosed for paying out or hauling sufficient pendant rope in response to detecting changes in the boom-mast angle from a desired angle Y thereby preventing the free end of the boom from raising due to extension and dropping due to retraction of the boom when the outer end of the boom is supported by pendant ropes. The system also provides means for pivoting the mast between a raised boom supporting position and a lowered transport position while maintaining tension on the pendant lines.</p> |
