A die casting machine includes a plurality of ejector pins capable of advancing and retracting together with respect to the internal portion of a die; an electric motor capable of driving the plurality of ejector pins; a position sensor capable of detecting the positions of the plurality of ejector pins; a force sensor capable of detecting the pressure which is given to the molding material inside the die by the plurality of ejector pins; a display device capable of displaying images, and a control device controlling the electric motor and display device. The control device includes a drive control part which controls the electric motor so as to generate a driving force making the plurality of ejector pins advance to the inside of the die after the start of injection and before die opening, and a display control part which controls the display device so as to display the position detected by a position sensor and the pressure detected by a force sensor along a common time axis.

An injection molding method of a resin molded article closes a first die and a second die by a predetermined clamping force, conducts pressure holding and cooling after filling a cavity formed between the first die and the second die with a molten resin, and opens the first die and the second die. The injection molding method conducts clamping, filling, pressure holding, and cooling for the first die and the second die by a clamping force previously specified on the basis of a sample with which pressure in the cavity during a cooling process indicates a minimum and which is specified from samples of clamping forces.

An injection molding machine includes: an acquisition unit configured to acquire, during a mold opening operation of a mold, at least one of a first measurement value relating to a resistance when a protrusion operation of an ejector pin to release a molding product from the mold in a mold-opened state is performed and a second measurement value relating to a resistance when an accommodation operation of the ejector pin is performed; and an estimation unit configured to estimate an amount of deposition of a mold deposit deposited on the mold, based on at least one of the first measurement value, excluding an element before the molding product is released or lowering a priority of the element, and the second measurement value.