| 摘要 |
PURPOSE:To effectively utilize generated shearing heat as self-heating source by a structure wherein a heater is detachably and adheringly provided onto the outer peripheral surface of the cylinder and, when the cylinder attains to a predetermined temperature, the heater is detached from the outer periphery of the cylinder in order to form a radiating gap for the over-heated portion to the predetermined temperature between the outer periphery of the cylinder and the heater. CONSTITUTION:When common power is turned ON, the heater 1 starts to raise its temperature under the state being adhered to the cylinder A. When the predetermined temperature is attained, the heater 1 is deenergized and at the same time electromagnets are also deenergized, resulting in detaching the heater 1 from the outer peripheral surface of the cylinder A by the action of springs 3. At this case, the temperature of the cylinder A tends to exceed the set temperature due to the shearing heat generated during the kneading action of a screw B. However the over-heated portion beyond the set temperature is radiated through the radiating gap 7 to the outside. Accordingly, when the molding is performed under the conditions that generate a fixed temperature equilibrium state for maintaining the predetermined temperature, the fabrication can be continued by applying only a starting energy to raise the temperature of the cylinder A up to the predetermined temperature. |
