Abstract: A cylinder temperature setting method in which the cylinder temperature distribution obtained in the condition setting operation is realized with fidelity, even when the molding operation is performed on injection molding machines which are different from the injection molding machine used for condition setting in the number and/or positions of heat sources arranged on the injection cylinder. A waveform representing the cylinder temperature distribution is obtained from the relationship between the temperatures of respective cylinder portions detected by thermocouples and the positions of the respective thermocouples when a conforming product is molded by a reference injection molding machine. The obtained waveform is stored and reserved in a record medium. The target values for temperature control of respective cylinder portions of another injection molding machine are obtained based on the reserved waveform, thereby realizing the cylinder temperature distribution obtained in the condition setting.

Abstract: A cylinder temperature controller for an injection molding machine in which an injection molding operation is performed while keeping the injection cylinder at a stable preset temperature regardless of disturbances such as the change of mold temperature or ambient temperature and the temperature rise caused by the shear compression of resin. A temperature regulator for carrying out PID feedback control of the injection cylinder temperature is provided with a PID adjusting means unit for automatic tuning. The actual temperature T of each portion of the injection cylinder is detected by a thermocouple. When the actual temperature T deviates from a predetermined temperature range defined by an upper limit [A+B] and lower limit [A-B] which are set on the basis of the preset target temperature A, an automatic tuning command is outputted to the temperature regulator. Upon receipt of this command, the PID adjusting unit sets the PID parameters again at a value suitable to the disturbance.