| 摘要 |
<p>PROBLEM TO BE SOLVED: To sufficiently improve mechanical strength to a high load, and surely position a bush to the bush fitting hole of a boss part. SOLUTION: Each of first bushes 20 having a lengthy axial dimension L1 and each of second bushes 21 having a short dimension L2 are independently integrally molded of a sintered oil retaining alloy, respectively. A bush 19 is constituted by each first bush 20 and each second bush 21, whereby the axial dimension of the whole bush 19 is set to a longer dimension L. Within the bush fitting hole 16A of each arm boss 16 (arm 9), each first bush 20 and each second bush 21 are fitted to the axial outside part and the axial intermediate part, respectively, and a connecting pin 24 is inserted to each insert hole 20A, 21A in such a manner as to be slidable. Both the end parts of the connecting pin 24 are integrally mounted on each bracket 18 of a bucket 10, whereby the bucket 10 is held on the tip side of the arm 9 in such a manner as to be turnable through the connecting pin 24.</p> |
