Abstract: A method is disclosed for controlling an injection molding machine of the type having an injection screw drivable for axial movement within an extrusion cylinder by a drive-controlled servo motor through a mechanical transmission, to provide a filling phase, a dwell phase, and a plasticization phase, the servo motor having a velocity command signal input connection, and the molding machine having sensors for screw position and injection pressure. The method includes the steps of presetting desired values for at least one of the injection pressure and the screw position; sensing the respective one of the corresponding actual injection pressure and actual screw position; and transmitting non-zero velocity command signals to the drive-controlled servo motor during at least the plasticization phase, and preferably also the filling and dwell phases, to move the injection screw within the cylinder.

Abstract: So that the injection nozzle (1) in an electrically driven injection molding machine may be driven free of shock into engagement with the mold (10), a spring has been interposed until the present time. The invention now proposes to delete this spring. The injection nozzle (1) is clamped between the stationary mold (10) and the injection unit (4) by two tie bolts or shafts (9) by the electric motor drive. Initially, the injection nozzle (1) is driven into engagement free of shock, for instance by presetting a brake ramp. Thereafter, the nozzle engagement force is adjusted as a function of the injection force or the pressure of the injection material, as the case may be, by way of a corresponding control device. In this manner, a constant equilibrium of engagement pressure and the opening force in the pressure is established, with selectable initial engagement tension. The energy consumption of the drive motor is reduced.