Method for controlling back pressure in electrically-operated injection apparatus.

摘要

The present invention provides a method for controlling back pressure in an electrically-operated injection apparatus, in which apparatus, rotation and forward movement of an injection plunger (1) within an injection heating tube (2) are carried out by an electric motor (19) as a driving source, backward motion of the injection plunger (1) during the charging of material is converted into rotational motion, and a rotating force thereof is controlled to control back pressure of the injection plunger (1), the method being characterized by using an electric motor (22) as a back pressure control means for the injection plunger (1), electrically measuring a backward force of the injection plunger (1) or molten material pressure within the injection heating tube (2) as the back pressure, and driving and controlling the motor (22) by feedback control so that the back pressure is in coincidence with a set value.