Abstract: A type face striking system for striking a type face to produces an imprint on a record carrier in a writing machine, the system including; 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; an actuating device including a magnetic field producing means in the form of a conductor coil connected for receiving an operating voltage for producing the electrically generated magnetic field; and a control unit connected to the coil and operative for successively applying thereto: a voltage pulse of a first polarity for causing the actuating device to produce a magnetic field which effects movement of the hammer from its rest position to its striking position; and a voltage pulse of a second polarity, opposite to the first polarity, for causing the actuating device to produce a magnetic field which effects movement of the hammer from its striking position toward its rest p

Abstract: Plural imprints of a selected character on a record carrier medium, which imprints are close together, mutually offset and partially overlapping, are generated in an office machine printer equipped with a typing element, in order to correct misprints or produce bold face prints.