| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a grapple which structurally eliminates the risk of a breakage of a bolt for attaching a cover for closing an opening of a bottom plate of a lower frame and the fall of the cover, associated with the breakage. Ž<P>SOLUTION: A bottom plate 2c of a tubular lower frame for attaching openably/closably a claw is provided with a circular opening 29. The circular cover 27 is turnably fitted into the opening 29. A support 32 is put on a top surface of an upper plate 2d which constitutes a part of the bottom plate 2c. A means for regulating the turning of the support 32 in the circumferential direction of the opening 26 is provided. A spacer 33 is externally fitted to a cover attachment bolt 31, and turnably inserted through an attachment hole 27a in the center of the cover 27. The spacer 33 is interposed between a head 31a of the bolt 31 or a nut and the support 32, so that the bolt 31 can be tightened in such a manner that the force of tightening the bolt 31 cannot be applied to the cover 27. A breaking force is hardly applied to the bolt 31 through the cover 27 is turned or displaced by backlash in the application of an external force from a treatment object. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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