| 摘要 |
PURPOSE:To manufacture a plyer by cold press-working by using a steel plate as a stock by selecting the thickness of a steel plate stock in accordance with the required thickness of a pivotally holding part, at which two pieces of unit bodies are cross attached to each other and are pivotally held by a pin. CONSTITUTION:The thickness of a stell plate stock is selected basing on the desired thickness of an unit body 3 of a finished plyer A at a cross-pivot holding part 5. On side face of a product stock blanked at the 1st stage is flushed with one side face of the nonbulged part 5 at the 2nd stage, and the thickness of a bulging part is made to two times the thickness of nonbulging part by providing a warp to the stock. At the 3rd stage, a part predetermined to be a holding front-tip part is inserted in a die, and is press-formed into the holding front-tip part 4. A gripping part 6 is bulged at the 4th stage, and a continuous chevron- shaped edge is formed at a holding piece 41 of the part 4 at the 5th stage. An unit body 3 of plyer a formed in this manner is heat treated, and then the two unit bodies 3 are pivotally attached to each other in one body by a pin 7. |
