Being the person in charge stopping system for the person in charge stopping system null expansion and contraction crane jib

摘要

PROBLEM TO BE SOLVED: To save the length of a telescoping cylinder by increasing the extension distance of a crane jib, and further, to reduce the weight of the whole of the jib.;SOLUTION: In a locking system for a telescopic crane jib, in particular for a mobile crane, a lock 5 is installed between a telescoping cylinder 10 and telescopic parts 1-4 by means of a locking unit 21 in order to extract and retract the telescopic parts 1-4, and the locking unit 21 is disposed on the telescoping cylinder 10 in such a way that it can be moved longitudinally. With this structure, the distance of movement of the locking unit 21 and the point of arrival thereof can be free from the moved quantity of the telescoping cylinder 10 and a selected arrangement thereof.;COPYRIGHT: (C)2010,JPO&INPIT