Drive circuit for a matrix printer

Abstract

A drive system for printers, in particular for matrix printers of a needle-type construction or hammer-type construction, exhibits an electromagnetic coil (L) coordinated to each printing element (6), as well as a magnetizable armature disposed opposite to each electromagnetic core (2), where the print element (6) is attached to the magnetizable armature, where the armature, in case of switched-off electromagnetic coil (L), is maintained in a rearward launching position, and where during a current-passing electromagnetic coil (L) the armature is launched with the print element (6) into a forward-disposed print position. In order to further increase the driving frequency for such electromagnetic coils (L), it is disclosed that a discharge time (t3), for the feeding back of the discharge current from the capacitor (C) into the electromagnetic coil (L) and via a resistor (R3) and a transistor (V2) into the capacitor (C), is provided following to a charge time (t2) for the capacitor (C), which charge time (t2) follows to a first pulse time (t1). Such a drive system is suitable both for electromagnetic-coil permanent-magnet systems as well as electromagnetic-coil clapper-armature systems.