A method of heating a thermoplastic plastic bottle or a preform and a method of controlling the temperature of the heating body used in the heating method

摘要

This invention relates to a heating method for shaping a thermoplastic bottle, which comprises inserting a heating member into the inside of a preform made of a thermoplastic plastic or the bottle and heating the preform or the bottle from both inside and outside with the heating member and a heater disposed outside in the heating process. The present method enables to control individually and accurately the temperature of this heating member, provide the heating member with a radiation energy distribution which changes in the longitudinal direction and carrying out heating suitable for the bottle to be shaped in order to produce a high-quality plastic bottle. Furthermore, the method of the present invention comprises sealing a metal which melts in a desired temperature range into the heating member, keeping the heating member at a predetermined temperature accurately for a long period of time by utilizing the latent heat of the metal to produce a high-quality plastic bottle. Similar means is used for heating the mouth of the plastic bottle to attain the optimum crystallization of the mouth.