Abstract: For use in a printing machine, such as an office typewriter, employing a replaceable printing head to be mounted on a carriage, there is provided a printing head fastening arrangement for releasably clamping the printing head to the carriage and permitting adjustable spacing of the printing head relative to the cooperating print support for containing the recording medium. The inventive arrangement enables the fastening and adjustment function to be integrated such that both functions can be carried out in one step. To this end, a rotatable pin is disposed upstanding from the carriage and provided with an operating element, which is resiliently seated relative to the printing head, for selectively engaging against a support surface formed on the printing head to clamp the printing head against the carriage.

Abstract: A printing mechanism is provided with a counter-balanced hammer bank such that the hammer bank and a counterweight are oppositely reciprocated by a pair of coaxial, identical, orthogonally oriented cams. Vibration of the printer even at high speed can be eliminated by completely dynamically balancing the system.

Abstract: The matrix head (1) of a matrix printer is guided close to the printing site (2) on a round bar (7) by means of profiled rollers (8) absorbing the reactive force during printing and being fixedly mounted at the matrix head (1) and by means of guide rollers (9) absorbing the force of gravity of the matrix head (1) and being resiliently mounted at this head, and is slidingly guided, at the head end facing away from the printing site (2), on a rail (15). A cord drive serves for displacing the matrix head (1), this cord drive comprising a cord (31, 32, 33, 34, 35) guided over a cord pulley (17) at the matrix head (1) and over further cord pulleys (19, 23, 24) and over a driving pulley (26), the ends (29, 30) of this cord being fixedly attached beside the ends of the round bar (7). Thereby the matrix printer can be constructed in a compact and lightweight fashion and can be operated with accuracy even in case of strong vibrations.

Abstract: A linear motor for a printer has stator teeth which are protected from dust and debris generated when the printing mechanism strikes the recording paper by a downward extension of the stator teeth, by a horizontal extension of the stator teeth, or by a horizontal extension of stator teeth which face away from the printing platen. The translating member of the motor to which the printing mechanism is attached has pole teeth spaced from the stator by mechanical rollers. The motor force acts close to the center of gravity of the moving members to reduce mechanical vibrations.

Abstract: There is disclosed herein a dot matrix tilting print head assembly in which the print head is rotatably mounted in a frame. A solenoid is provided for rotating the print head a controlled distance so that printing occurs between previously printed dots. A pin extending from the print head is positioned into a larger diameter hole in the frame for controlling the distance to be one half of the center-to-center distance between printed dots. This entails maintaining very low tolerances for the mechanically moving parts. In addition, there is provided support members for allowing the removal of the print head alone from the frame means.

Abstract: A print head carriage assembly for a serial printer apparatus, the carriage including a platform having two parallel channels extending laterally through the frame member for receiving self-aligning bearings and carriage guide rails; a central seat within the platform for seating the housing of a matrix print head with the longitudinal dimension of the print head oriented normal to the longitudinal axes of the channels, locking means for securing the matrix print head in place about said central seat with the neck of the head extending substantially normal to the axes of the channels, manifold adjustment means for adjusting the position of the head within the seat relative to the axes of the channels; and means for engaging the platform to a drive means for driving said platform laterally along said guide rails.

Abstract: A carriage for positioning a print mechanism in front of a record medium and moving the print mechanism back and forth in front of the record medium with facility for retracting the print mechanism to permit insertion of a ribbon and biasing the print mechanism forward toward the record medium against an adjustable stop. The retracting mechanism being further adjustable for retracting the printing mechanism completely out of the carriage for removal therefrom.