| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the interference of the pulled-out part of a piping with an attachment by providing a joint insert hole on the tip side surface of a top boom body, and setting a joint for attachably and detachably connecting a piping inserted into a boom to the piping of the attachment on the boom tip through the joint insert hole. SOLUTION: A boom 1 mounted on a working vehicle such as crane is formed of a base boom body, a middle boom body and a top boom body 4, and a jib 5 is installed to the boom head 4a of the top boom body 4, the hydraulic piping H1 of the jib 5 is inserted extending from the base boom body to the middle boom body, and its tip is connected to a cylinder-side piping H2 through a joint 9 provided on one side surface part of the boom head 4a. A joint through hole 13 is provided on the side wall having the joint 9 of the boom head 4a, and the connecting block 10 of the joint 9 is set over the outside and inside of the boom in the state extending through the joint through hole 13. According to this, the attachment and detachment of the jib 5 is facilitated.</p> |
