Fault detection method on a drive unit for an injection molding machine involves individual actuation of components of the drive system and reporting of faulty component to machine control unit

摘要

The position of a hydraulically operated piston(5) is monitored by a stroke sensor(S1) and one or more valves(6,7) in the fluid supply line are preceded by and followed by pressure sensors(P1,P2,P3). If the actual piston position deviates from a set position the components of the drive unit governing the movement are individually actuated to check their serviceability. The position of a hydraulically operated piston(5) is monitored by a stroke sensor(S1) and one or more valves(6,7) in the fluid supply line are preceded by and followed by pressure sensors(P1,P2,P3). If the actual piston position deviates from a set position the components of the drive unit governing the movement are individually actuated to check their serviceability. Any component identified as faulty is reported to the machine control unit and/or a visible indication is made. Additional information about the identified faulty component cab be shown during the identification stage. Valves and slides(6,7) are checked in their open condition after shutting off the next component in the fluid flow direction and recording readings from the pressure sensors. The next component is checked in advance to ensure that it is fully shut off. Checking of valves or slides is carried out by starting at the piston end of the circuit and working on one after the other towards the pump(1).