Injection molding machine and method of controlling the injection molding machine

(Amended) A method of controlling an injection molding machine including a screw rotating motor for rotating a screw inserted into a heating cylinder about the axis of the screw, and a screw movement means having an actuator for moving the screw axially rearward and forward, wherein

• an axially rearward molding material pressure received by the screw in injection and metering is detected and output as an electric signal,
• an electric disturbance of the electric signal is eliminated by switching a constant to a value different between the injection and the metering, and
• the electric signal from which the electric disturbance has been eliminated by the different constant is fed back and an axial pressure of the screw by the screw movement means is controlled.

(Amended) An injection molding machine including a screw rotating motor for rotating a screw inserted into a heating cylinder about the axis of the screw, and a screw movement means having an actuator for moving the screw axially rearward and forward, wherein the machine includes

• a detection means for detecting an axial pressure of the screw,
• a pre-pressure addition means for previously adding a pre-pressure acting in the opposite direction of an axially rearward molding material pressure received by the screw to a detection means and/or the screw so as to adjust the pre-pressure depending on a molding material pressure, and
• a screw axial direction pressure control means for controlling an axial pressure of the screw by the screw movement means based on a difference between the pre-pressure previously added by the pre-pressure addition means and the molding material pressure detected by the detection means.

(Amended) An injection molding machine including a screw rotating motor for rotating a screw inserted into a heating cylinder about an axis of the screw, and a screw movement means having an actuator for moving the screw axially rearward and forward, wherein the machine includes

• a detection means for detecting an axial pressure of the screw and outputting it as an electric signal, and
• a filter for eliminating an electric disturbance of the electric signal output from the detection means by a predetermined constant,
• wherein the constant of the filter for eliminating the electric disturbance can be switched between the injection and the metering.

An injection molding machine including a screw rotating motor for rotating a screw inserted into a heating cylinder about its axis, and a screw movement means having an actuator for moving the screw axially rearward and forward,

• wherein the actuator of the screw movement means is disposed on the heating cylinder side and
• the rear end of the screw is coupled inside of a rotating output section of the screw rotating motor.