| 摘要 |
PURPOSE:To produce a coil spring of stable quality and dimensional accuracy inexpensively by cooling a heated spring blank material quickly while winding the material like coils and hardening the material. CONSTITUTION:While a bar- or wire-like spring blank material 1 is transferred with feed rollers 2, 2, 2, lead screws 3, etc., electricity is conducted to the material from an electric power source device 9 through electrodes 8, 8 in rolling contact with the material 1, whereby the material 1 is heated to a prescribed temp. A mandrel 4 fixes the terminal of the material 1 with a clamping mechanism 5, winds the material 1 and immerses the material into cooling liq. 7 while winding and forming the material like coils thereby cooling the material quickly. Upon completion of coiling and hardening, the coil spring product is removed from the mandrel 4. Since the material is hardened in a restrained state by the above-mentioned method, the deformation by the heat treatment is prevented, and the dimensional accuracy is improved. The products of stable high quality are obtained with the shorter time required from heating up to hardening, with less consumption of energy and under prevention of imperfect hardening and decarburization. |
