METHOD OF JOINING SHEET MATERIALS AND JOINING EQUIPMENT

PROBLEM TO BE SOLVED: To joint sheet materials regardless of existence of surface processing and secure sufficient joining strength by continuously cutting and bending thin sheet materials through a joint action of dies and a punch having a cutting edge portion and a bending edge portion. SOLUTION: Two sheet materials 18a and 18b to be jointed are supplied horizontally at a specified position on dies 12 and an upper die having a punch 11 starts to descend and its holding plate folds and fixes the sheet materials 18a and 18b and then cutting and bending are started with the punch 11. The sheet materials 18a and 18b are cut with three cutting edge portions 17a-17c of the punch 11 and a peripheral side wall of the die hole 13, and at the same time, the tops of cut pieces 19a and 19b are pressed downward to be bent by about 45 deg. by an inclined face 14a to constitute a bending edge portion 16. Subsequently, the cut pieces 19a and 19b are pressed and bent approximately to the right angle by a perpendicular face portion 15 and the cutting is extended/ expanded by cutting edge portion 17d and 17e, and only that portion is bent to about 45 deg. by an inclined portion 14b. Thus, any sheet material which can be cut and bent can be jointed.