| 摘要 |
PURPOSE:To give reverse gradient accurately to a groove and, at the same time, make the inner circumference a spherical face by supporting a radially slidable liner by one die to plural grooves that have no reverse gradient ironing a material by another die. CONSTITUTION:In manufacturing a part 1 by forging, the tip of a lock pin 11 at the center of a lower die 4 is set inside of a radial liner die 7 and covered with a preliminarily formed material 1' fitting a groove 2a to the die 7. As the groove 2a to has no reverse gradient, this fitting is easy. When an upper die is lowered, the outer circumference face 1b is ironed by a projected part 5, and reverse gradient is given accurately to the lower part of the groove 2a supported by the die 7. At the same time, the inner circumference face is formed by coining spherically. Next, when the pin 11 is lowered by a specified amount, the die 7 moves in centripetal direction being energized by a coil spring 10 and comes off from the groove 2. The part 1 is easily taken out from the die 7 by raising the die 3, and pushed out by downward movement of an eject pin. |
