2011 年 2011 巻 56 号 p. 19-24
The production of coil spring requires the precise dimension control of coil diameter and free length. Friction between coiling pin and wire material has the key role in controlling the dimension of coil spring products. In this research, experiments on the effect of newly developed coiling pin unit with supersonic vibration being applied. The obtained result shows that the machine capability has improved significantly.