Control device of injection molding machine, injection molding machine, and method of controlling injection molding machine

A method of controlling an injection molding machine, in which outputs of a plurality of heating units for a plurality of zones, respectively, into which a cylinder is divided in a flow direction of a molding material are individually controlled based on a temperature measured by a temperature measurer, the method comprising:

• a process of acquiring a first output of a heating unit provided in a predetermined zone, among the plurality of heating units, in a steady state when a screw provided inside the cylinder is stopped;
• a process of acquiring a second output of the heating unit at a time of molding when the screw is operated;
• a process of calculating a difference in the first output and the second output;
• a process of raising a set temperature of a zone upstream of the predetermined zone in the flow direction, in an initial stage of a continuous operation in which the injection molding machine manufactures a molding product repeatedly, when the difference indicates that the second output is larger than the first output by more than a predetermined condition, the upstream zone closer to a feed port of the cylinder than the predetermined zone;
• and
• a process of controlling an output of a heating unit provided in the zone upstream of the predetermined zone based on the set temperature during subsequent stages of the continuous operation,
• wherein an amount by which the set temperature of the upstream zone is raised increases as the difference increases.