METHOD OF DETECTION OF ABNORMALITY OF SQUEEZE PIN AND MOLDING MACHINE

A molding machine that can stably detect the abnormality of a squeeze pin, and a method of detecting the abnormality of a squeeze pin are provided. A molding machine comprises: a clamping device for clamping a fixed mold and a movable mold; an injection device for supplying melt into a cavity formed by the fixed mold and movable mold; a squeeze pin(75) that can advance or retreat relative to the cavity; a hydraulic cylinder(78) which has a piston(79) fixed to the squeeze pin and drives the squeeze pin; a hydraulic circuit(83) for controlling the flow of a working fluid supplied into a rod side cylinder chamber(78b) and a head side cylinder chamber(78a) divided by the piston of the hydraulic cylinder; a control device(95) constructed to control operations of the clamping device, the injection device, and the hydraulic circuit; and sensors(91,92) for detecting a physical amount indicating the operation state of the squeeze pin, wherein the control device controls operations of the clamping device, the injection device, and the hydraulic circuit in order to repeat a molding cycle including an injection process, a pressure applying process, a carrying out process, and a lubricating and cooling process, and the control device judges whether any abnormality of the squeeze pin is present or not based on the comparison of a physical amount detected by the sensor in the lubricating and cooling process with a predetermined reference value.