To enable production cost to be decreased by reducing the amount of material to be used in addition to easiness of manufacture due to small man hour required for manufacture.
On the tip end of the screw shaft part 4 of a bolt main body 1 capable of being welded to a base, a bolt in which an expanded head part 2 for engagingly locking a chuck is provided aside via a breaking narrow neck part 3, and a sleeve capable of making plastic deformation through a member to be clamped is loosely fitted to the screw shaft part 4 erected on the base by welding the bolt on the base and this sleeve is brought in press contact with the member to be clamped while being caulked from the side surface by means of a caulking tool so that the sleeve may be formed in a nut in which a female screw part is formed and simultaneously the member to be clamped is tightened to the base. In addition, the engagingly locking claw of the chuck stored inside of the caulking tool is engagingly locked to the expanded head part 2 of the bolt main body 1 and tracted so that the expanded head part 2 may be broken and removed from the narrow neck part 3.
MIZUNO HIROMICHI
WAKIHARA TAKEYOSHI
