| 摘要 |
<p>A self-erecting tower crane (20) for use on a construction site is supported at a top end (102) of a tower (26) that includes tower sections (114) assembled in an end-to-end relationship relative to one another along a tower axis (38). The tower crane (20) includes a boom assembly (28) for selectively raising tower sections (114) above ground. A boom support structure (24) has an upper portion (30) that rotatably supports the boom assembly (28) relative to the tower axis (38), and a lower portion (32) that is configured and sized for mounting on and releasably securing to the tower top end (102). A self-raising sleeve (22) mounts on the tower (26) for axial movement therealong, and selectively and releasably supports the boom support structure (24) on the tower (26). The sleeve (22) and the boom support structure (24) include a side opening (116) that is configured and sized for allowing a tower section (114) to be assembled to the tower top end (102) for the self-erection of the tower crane (20).</p> |
