Method for tendency control of the switching point in an injection moulding process

摘要

The invention relates to a process for trend control of the change-over point from injection pressure to holding pressure on injection moulding machines for processing thermoplastic moulding compositions. It contains the setpoint entry of an operating window for pressure or force and time or path, the setpoint entry of an operating band for the temperature, the definition of the change-over point within the operating window, measurement of the current pressure or of the force and comparison with the setpoint entries of the operating window of each injection cycle at the instant of change-over and displacement of the change-over point in dependence on the differences from the setpoint entries of the operating window and of the operating band according to specific criteria. In addition, the invention relates to an injection moulding machine for carrying out the process. IMAGE