SWIVELLING WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To prevent generation of unexcavated portion by making offset the widthwise center line of arm and bucket to an offset member mounting side with respect to the widthwise center line of first and second booms under the condition where an excavation working machine is directed forward/rearward. SOLUTION: A first boom 10 is mounted to a turning base of an excavation working machine so as to move up and down freely in the forward and rearward direction, and to a tip of the first boom 10 a second boom 11 is mounted so as to be turnable right and left freely. To the second boom 11 a third boom 12 is mounted so as to be turnable right and left freely, and to the third boom 12 an arm 13 having a bucket 14 at its tip is mounted so as to be turnable up and down freely. To the center line 20 of the boom 10 and the boom 12 the lateral center line 21 of an arm cylinder 17 and the bucket 14 are arranged in an offset manner only by a distance Y to the side of offset rod 30 and offset cylinder 31. Accordingly, a stay 23 pivotally supporting the rod 30 is prevented from abutting on a groove or the like and being damaged thereby, and generation of unexcavated portion can be prevented.