INJECTION MOLDING MACHINE HAVING A PROGRAMMING DEVICE AND A METHOD OF OPERATING THE SAME

摘要

INJECTION MOLDING MACHINE HAVING A PROGRAMMING DEVICE AND A METHOD OF OPERATING THE MACHINE An injection molding-machine, particularly for plastics, comprises an injection cylinder having an injection discharge at one end and an inlet for material to be plasticized which is spaced therefrom. An injection screw is rotatable in the cylinder and it is also movable by the force of a fluid pressure applied against a piston so that it will advance in the cylinder. The means for supplying a pressure for operating the piston is connected to a control device which in turn is connected to means for measuring the pressure for actuating the piston and also means for measuring the distance of movement of the injector screw and the velocity of its movement. The operating pressure for advancing the screw is continuously measured and the switching device which is connected to the control is operated so that upon reaching a predetermined hydraulic pressure and after a predetermined movement of the screw and a predetermined filling distance movement, a first mold filling phase is carried out in which the injection velocity is controlled as a function of the covered distance and until a predetermined hydraulic pressure is reached. The control thereafter effects an after pressure phase in which the after pressure is applied for a predetermined time control period on the basis of the operating pressure.