Abstract: Mechanism for automatically adjusting the feed increment according to the type of ribbon in a ribbon cassette is characterized by a pawl and feed ratchet and to means operative by coded features on a cassette, when the cassette is mounted, to control the interval of engagement of the pawl and feed ratchet.

Abstract: An engage/disengage coupling between a drive and driven part for imparting rotational force without axial force components.

Abstract: The invention is a mechanism for raising and lowering the ribbon in typewriters to make typed text visible. No separate drive such as a motor or magnet is required to raise the ribbon. The ribbon is raised by means of a spring-loaded bar prior to each character reproduction. To accomplish this, an armature of a control magnet releases a pivoting lever and the spring loaded bar. A pin wheel, driven by a motor and acting on the lever serves to return the bar and allow return of the ribbon. The motor is energized after each character reproduction to advance either a type element carrier or the paper carrier by one character space. In typewriters with ribbon spools fixed to the machine frame, the ribbon spool drive also can be derived from the spring powered bar.

Abstract: Disclosed is a preferably transparent removably mounted cover plate for covering the top opening or printing point area in a printer, e.g. a needle printer, which serves to reduce noise and to prevent the introduction of foreign substances and dust. Of particular advantage is the inclusion on the cover plate of paper guide elements, a switch actuating cam which acts on a switch to shut off the machine when the cover plate is removed or swung out, and a paper tear-off edge.

Abstract: An electromechanical printer having characters of a type font located on radial spokes of a circular type disc is disclosed. The type disc is normally arrested and connected to be driven about its axis by a unidirectional motor source via a slip clutch. Selection-print activating mechanism responsive to source, e.g. keyboard, generated mechanical outputs serve to select a character stop, in an assembly of character stops, corresponding to characters located on the spokes of the type disc and, incident to selection of a character stop, to release the normally arrested type disc. The type disc is provided with counterstops adapted to engage selected character stops positioned in the path thereof and to move the character stop assembly to a frame supported final positioning stop which arrests the type disc with the selected character opposite a print point.