| 摘要 |
In a workpiece joining method an end portion of a bolt shaft 1 is inserted into each hole 3a of at least one workpiece 3, and a sleeve 2 is placed onto an end of each bolt shaft. Then, an upper die 5 is lowered toward the workpiece supported on a lower die 4 so that while the workpiece is being pressed toward base end portions of the bolt shafts 1, a tightening portion 6b of each nose 6 provided on the upper die 5 draws the outer wall of the corresponding sleeve 2, thus tightening the sleeves. The tightened portion of each sleeve progressively enters a relief portion 6c formed above the tightening portion. The thrust of the noses 6 does not act directly on the bolt shafts in the direction of their axes, so that the joining jig can apply a tightening force without being restricted by the strength of the bolt shafts. |
