Type face striking system in an office writing machine

A type face striking system for striking a type face to produce an imprint on a record carrier in a writing machine, said system comprising:

• an electromagnetically actuatable printing hammer movable under the influence of an electrically generated magnetic field between a rest position and a striking position for striking the type face;
• actuating means including magnetic field producing means in the form of a conductor coil connected for receiving an operating voltage for producing the electrically generated magnetic field;
• control means connected to said coil and operative for successively applying thereto:
• a voltage pulse of a first polarity for causing said actuating means to produce a magnetic field which drives said hammer from its rest position to its striking position;
• and a voltage pulse of a second polarity, opposite to the first polarity, initiated substantially immediately upon striking of the type face by said hammer, for causing said actuating means to produce a magnetic field which drives said hammer from its striking position toward its rest position;
• and means for detecting impact of said hammer against a type face when said hammer reaches its striking position and means for producing, in response to such detection, a signal which initiates production of the voltage pulse of a second polarity.