| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a boom telescopic mechanism capable of making stability performance generally equal to that of a one-cylinder telescoping mechanism since the total weight of the telescopic mechanism is generally equal to the one-cylinder telescopic mechanism while a time required for a telescopic boom to be brought in an extended state is shorter than that of the one-cylinder telescopic mechanism since basically the boom telescopic mechanism is a two-cylinder telescopic mechanism. <P>SOLUTION: This boom telescopic mechanism comprises a first telescopic cylinder 47 and a second telescopic cylinder 48 capable of providing a telescoping stroke of an amount equivalent to one stage of boom by adding the telescopic movements of both cylinders to each other, boom fixing means 49 to 52, a first cylinder/boom connection means 53 and a first fixing pin drive means 54 fitted to the cylinder tube rod side end part 47b of the first telescopic cylinder 47, and a second cylinder/boom connection means 55 and second fixing pin drive means 56 fitted to the cylinder tube anti-rod side end part 48c of the second telescopic cylinder 48. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
