Method for continuously checking the production of security printing machines, application of said method and device for performing the method

摘要

The ink-agitator (1) is supported and guided by fixed means between pedestals (2) and (3) above an ink fountain containing security ink. It is driven in alternate movement on its guiding means and its tip is dipping into the ink. Bore (11) receives a detector head in the form of a transformer with primary winding arranged for normally producing a "zero" magnetic field, adjustable ferrite core place in such a manner that the "zero" magnetic field is obtained for a standard magnetic property of the security ink, and secondary winding going out of balance and issuing a signal if the magnetic property of the ink into which the tip of the ink-agitator is displaced undergoes modifications. The output signal is transmitted to feed line (4) with slide contact (6) whereas the ground pole is connected through wire (5) and sliding contact (7).