Abstract: 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).

Abstract: 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).

Abstract: A control method for detonators (1) fitted with an electronic ignition module (15). Each module (15) is associated with specific parameters including at least one identification parameter and one explosion delay time, and includes a firing capacitor and a rudimentary internal clock. The modules (15) are capable of establishing a dialogue with a firing control unit (17) fitted with a reference time basis. The identification parameters are stored in the modules using a programming unit (18); the specific parameters are stored in the firing control unit (17); for each successive module, its internal clock is calibrated using the firing control unit and the associated delay time is sent to the module; the modules are ordered to load the firing capacitors; and a firing order is sent to the modules using the firing control unit, triggering off eventual resetting of the internal clocks as well as a firing sequence.