| 摘要 |
PROBLEM TO BE SOLVED: To provide a joint jib for a crane allowing recognition of a joint error between jib sections before connecting connection brackets together in either of a vertical assembly method and a horizontal assembly method so as to prevent an error in the connection order for securing strength, stability, and safety sufficiently. SOLUTION: In this joint jib, connection error preventing means 25, 30 prohibiting pin holes 27, 28 between connection brackets 20, 21 in jib sections 2C, 2F connected to each other from matching with each other so as to prevent erroneous connection are arranged properly in the jib section connection brackets. When the respective jib sections are connected together in a normal connection order, matching of the pin holes is not prevented by means of the connection error preventing means, and if a connection order is wrong, matching of the pin holes is prevented by means of the connection error preventing means. |
