SPRAYING MACHINE AND METHOD FOR DETECTING TOOL INTERNAL PRESSURE

Abstract

An injection molding machine 1 comprises: an injection device 10 designed to inject resin material molten in a heating cylinder 11 from a nozzle 12, inside of which a screw 20 is arranged; a mold 75 comprising a stationary mold 76 and a movable mold 77 and having a cavity 75a to be filled with resin material; a load cell 60 designed to detect a pressure acting on the screw 20; and a control device 100 designed to control an internal mold pressure.The control device 100 comprises: a pressure loss sensing unit 111, designed to detect as pressure loss the pressure detected by the load cell 60 when resin material is injected from the nozzle 12, which is in contact with the stationary mold 76, while the stationary mold 76 and the movable mold 77 are open; an injection pressure sensing unit 112, designed to detect as injection pressure the pressure detected by the load cell 60 when resin material is injected from the nozzle 12 into the cavity 75a while the mold 75 is closed; and a virtual mold cavity pressure calculation unit 114, designed to subtract the pressure loss from the injection pressure to calculate a virtual mold cavity pressure V.