| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable commonality between a standard boom and a pivotal-supporting and connecting member of a two-piece boom comprising a first boom in which the pivotal-supporting and connecting member pivotally supported on and connected to a boom supporting portion is provided on the side of its base end, and a second boom, the base-end side of which is pivotally supported on and connected to the side of the leading end of the first boom and the arm of which is pivotally supported on and connected to the side of its leading end. <P>SOLUTION: A main body portion 51 of the second boom 18B is formed in such a shape that a horizontal width of a base end-side portion Y is smaller than that of a leading end-side portion X. The base end-side portion Y of the second boom 18B is inserted between right and left side walls 29 of the first boom 18A, and pivotally supported on and connected to it in such a manner as to be turnable rightward/leftward on the axis. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
