Fault monitoring system for press drive - out of phase synchro resolvers between drive and control drum

摘要

One of the two synchro resolvers used in the fault monitoring circuit for the stress acts as a transducer. The connection from the mains to the stator of the transducer has an interrupter switch connected with the actuating switch which releases the stroke of the press so that when the actuating switch is closed then the interrupter switch is opened. The drive system switch of the press control system acts in conjunction with the closing of the interrupter switch. This arrangement checks automatically the operational reliability of the drive interrupter before each stroke of the press. This ensures that the press cannot continue working in case of a fault if the drive circuit relay has burnt out.