| 摘要 |
PURPOSE:To detect foaming pressure by transforming a force acting in the opening direction of a mold caused by a foaming pressure of a foaming synthetic resin material in the mold to a positional signal by means of a position detecting device, performing feedback thereof to a servo control part and transforming a torque generated by controlling a servo motor under a condition where a distance between molds is kept const. to an electric voltage. CONSTITUTION:A raw material bead of a foamable synthetic resin e.g. a foamable polystyrene is filled in a molding space 15 of a mold for foam molding and a process consisting of heating, foaming and cooling is performed. In this time, a position of a movable mold 5 is detected by means of a position detecting device 11 and it is transformed to a position pulse, which is fed back to a servo control part 12. The servo control part operates the difference between a pulse at a standard position and a pulse at a detecting position to obtain the deviation and furthermore it determines a speed control command based on this position loop gain and other transmitting function and controls a servo motor 9 so as to make the deviation zero. In this case, it is possible to detect a foaming pressure by transforming it to an electric voltage and detecting by means of a torque detecting device 13 of the servo motor 9. |
