| 摘要 |
PURPOSE:To improve the yield of material and reduce the number of processes by thickening the back edge of the prototype of sickle by pressing, and making the back edge part thicker than that of steel plate used for the edged tool by thickening it uniformly. CONSTITUTION:A prototype 5 of a sickle is made by blanking a steel plate for cutlery in the first process. The back edge 7 of the blade 6 of the prototype 5 is thickened by pressing in the second process. In the third process, the blade 6 of the prototype 5 is bent to chevron-shaped section by press forming narrowing the width longitudinally and with the back edge facing the front, and the back edge 7 is thickened uniformly. In the fourth process, an edging is performed to the cutting part 8 in the blade of the prototype 5. |
