| 摘要 |
PURPOSE:To form a bead having excellent water and dust proofings by forming the waving end which is bent in the depth direction of a groove simultaneously with forming a gutter shaped return groove from a plate blank material, then by overlapping the return waving end on a plate blank material. CONSTITUTION:A gutter shaped return groove 12, the waving part 13 bending therealong and a recessed part 12a are formed in cooperation with upper and lower dies 6, 7 with descending the upper die 6 and plate holders 111, 112. The center of the waving part 13 is cut with fitting the return groove 12 of a blank plate material 1 and the half of the waving part 13 between the separate up and down dies, and a return waving end 17 is formed. A waving end 17 is formed with pressing by a punch 26 by overlapping a reinforcing plate on the upper face of which the blank plate material 1 is fixed on a supporting stand 24. The return groove 12 is not cracked at forming work time and consequently the bead having excellent water and dust proofings is formed. |
