| 摘要 |
<p>PROBLEM TO BE SOLVED: To maintain the hang up load performance of a telescope boom and obtain a compact telescope boom by driving a fifth step boom of an interlock device against a fourth step boom with telescope motion in response to the displacement of the fourth step boom for driving a third step boom with the telescoping of a third hydraulic cylinder. SOLUTION: In a telescoping drive device 20, the telescoping of a second step boom 12 for a first step boom 11 and the telescoping of a third step boom 13 for the second step boom 12 are carried out by first/second hydraulic cylinders 21, 22 respectively. A continuous telescoping between the third step boom 13 and a fifth step boom 15 are carried out by an interlock device 26 through a wire rope 31 between the third hydraulic cylinder 25 and respective booms 13-15. In order words, the interlock device 26 is telescoped and driven while interlocking the fifth step boom 15 for the fourth step boom 14 in response to the displacement of the fourth step boom 14 for driving for the third step boom 13 in coping with the telescoping of the third hydraulic cylinder 25.</p> |
