Abstract: A method of providing an ink jet printing head with piezo-crystals comprises the steps of providing a plateshaped basic printing head body including an ink supply reservoir, ink pressure chambers, ink exit openings, ink outlet channels which connect the pressure chambers with the ink exit openings, and ink inlet channels for connecting the pressure chambers with the ink supply chamber; providing a membrane plate; providing an piezo-ceramic plate; attaching the piezo-ceramic plate face-to-face to the membrane plate; attaching the membrane plate face-to-face to the basic body; and subsequent to attaching the piezo-ceramic plate to the membrane plate, entirely separating piezo-crystals from the piezo-ceramic plate by providing closed-course cuts through the piezo-ceramic plate such that a separate piezo-crystal is obtained in alignment with each pressure chamber.

Abstract: A method and apparatus to avoid disturbing an inexperienced operator of a text station, such as a typewriter or other word processing device which is equipped with a one-line display device (6), when the text approaches the end of the display device and a word must be hyphenated. In a typical conventional text station having a one-line display device, the current typing position is marked on the display device by a cursor (9) which automatically advances toward the right margin (10) until a line feed is initiated, whereupon the cursor jumps to the left margin (11) on the display device and the previously displayed text is erased. If a word is divided, the first part of the divided word is then no longer visible at a conventional text station after the automatic line feed, and for inexperienced operators this disturbs the typing rhythm.

Abstract: A ribbon cassette for an office machine, composed of: a cassette housing removably mountable in the machine, the housing having an entrance opening, an exit opening, an openable cover and elements constituting deflection points; a supply spool and a take-up spool having a core, each of the spools being removably mounted in the cassette housing; a carbon ribbon initially wound in the form of a coil on the supply spool, the ribbon having a leading end at the outer surface of the coil to be received by the take-up spool core to permit the ribbon to be wound up on the take-up spool while being unwound from the supply spool; and a fastening member secured to the leading end of the ribbon for threading the ribbon around the deflection points; and wherein the core is formed for enabling the fastening member to be fixed thereto to aid winding of the ribbon on the take-up spool.

Abstract: A process for inscription of parts from plastic material whose color can be changed through the effect of an energy radiation used for providing alphanumeric characters or other symbols on the key buttons of a keyboard. The office machine keyboard completely equipped with blank key buttons is for that purpose moved relative to the energy radiation, for instance a laser beam, with the coordinated character or symbol being inscribed on each key button by the energy radiation in accordance with stored data as the key button proceeds into the effective area of the energy radiation.

Abstract: For underlining a text section a command is typed both before and after the text section in the typing sequence, which command causes the storing of position values in two registers. The underlining is then performed underneath the already entered characters. A command for line advance, facultatively in connection with returning the printing head to a left position, ensures that the underlining will be performed prior to the line advance, but that the conditions for the underline will be retained also for the next line.