Injection molding device and method for controlling injection molding device

An injection molding device that performs injection molding of a molded product using a mold formed of a fixed mold and a movable mold, the injection molding device comprising:

• an injection unit configured to inject a material for the molded product into the mold;
• a mold opening and closing unit to which the mold is attached and configured to open and close the mold;
• and
• a control unit configured to control the injection unit and the mold opening and closing unit, wherein
• the injection unit includes
• a material supply portion configured to supply the material,
• an injection portion communicating with the material supply portion and configured to inject the material into the mold, and
• a pressure detection portion configured to detect a pressure of the material in the injection portion,
• a waveform of the pressure detected by the pressure detection portion in an injection period that is a period during which the injection portion performs an injection operation includes a first peak waveform and a second peak waveform that exists after the first peak waveform, and
• the control unit controls the injection portion based on a pressure value included in the first peak waveform.