| 摘要 |
<p>PROBLEM TO BE SOLVED: To guide the relative expandable members to the sides to mutually fix them by forming an adjustment device of a fixing means by a piston cylinder device, and mounting the piston cylinder device in an inner expandable member operated by the supply or discharge of the fluid pressure. SOLUTION: A jib for crane comprises an outer expandable member 12 and an inner expandable member 13 expandable along the longitudinal direction inside the outer expandable member 12. A fixing means is mounted for retaining the relative rotational position of the outer and inner expandable members 12, 13. A stopper 9 is fixed inside the outer expandable member 12. The piston 2 is movably accommodated inside the cylinder 1. A bottom part 3 of the cylinder 1 is connected to a mounting member 16 by a fastening bolt 5, and the mounting member 16 is fixed to an internal vertical support 17 of the inner expandable member 13. Whereby the expandable member can be correctly and infinitely fixed from a part which can not easily access.</p> |
