Abstract: A marking device (10) comprises a frame (1) (of frame plates (12,14)) to which are fixed first and second motors (16,18). A carriage frame (40) is pivoted in the frame about a screw axis (22). A marking head (30) is mounted on the carriage frame for movement in a direction parallel the screw axis. A drive screw (20) is rotationally mounted in the frame along the screw axis and is driven by the first motor (16). The carriage frame is journalled on said drive screw to permit said pivoting about the screw axis. The marking head is driven by rotation of the screw, the carriage frame being pivoted by the second motor. The carriage frame (20) comprises a bar (32) on which the marking head slides. The bar is disposed parallel the drive screw. The bar has at each end an arm (34,36) pivoted on bearings (35,37) on the drive screw. One arm (36) has an extension (66) fixed to a belt (58) disposed around two idler pulleys (62,64) and a motor pulley (60) driven by the second motor.

Abstract: Disclosed is an improved serial impact printer which both prints and serrates a document. The printer includes a print wheel which is rotated to position a selected character in front of an anvil. The print wheel includes a wheel-like circular member having print characters at the end of fingers which extend from the top of the print wheel's perimeter. An impact mechanism pressures the selected print character against the anvil, the document being positioned between the selected print character and impact mechanism. The impact mechanism includes a d.c. motor which turns a threaded shaft which is engaged with a threaded hole in the end of a hammer. Counterclockwise motion of the d.c. motor advances the hammer's head to pressure the back of the print character against the anvil, thereby printing and serrating the document with the selected character. Thereafter, clockwise motion of the d.c. motor restores the impact mechanism to its original position.

Abstract: An electric typewriter for printing indicia includes indicia-selecting and typerwriting mechanisms. Keys are associated with the indicia through a mechanical matrix which controls the positioning of a ball containing the indicia.