It is often necessary to perform actuation movements and to generate force effects at different times or consecutively in injection molding machines. The actuation movements occur over more or less large displacements if little or no displacements are to be overcome when force effects are applied. The varying requirements occur in the operation of injection molding machines in connection with, for example, a pusher type screw unit of extruders wherein the plasticized plastics melt is metered into an injection mold by displacing the pusher type screw and the melt is subsequently subjected to a so-called dwell pressure.
Similar varying requirements also arise when operating a closing unit of an injection mold where two mold halves are movable towards or away from each other for the respective closing and opening of the injection mold, wherein the injection mold must be subjected to a specific closing force in its closed position.
It is therefore an object of the present invention to optimize the operating mode of a true-to-type displacement and/or actuating force driving device for injection molding machines.
A further object of the invention is to provide an economical displacement and/or actuating force drive device for injection molding machines.
Another object of the invention is to provide a device whose electromechanical displacement drive apparatus overcomes relatively larger actuation travels rapidly and safely.
Yet another object of the invention is to provide a device whose electromagnetic displacement drive device provides the necessary dwell pressure and/or closing forces.