Abstract: A printing head structure of calculator, including a belt type printing head the outer periphery of which is disposed with at least one group of fine characters and at least one group of coarse characters. The fine characters have the same symbols and numerals as the coarse ones, while having different thicknesses and letterforms. By means of a printing control program of the calculator, the printing head is able to print out a positive or negative result respectively by fine characters or coarse characters so as to apparently visually distinguish the positive result from the negative one and thus achieve a reliably reminding effect.

Abstract: A set of characters is provided wherein each character is formed by arranging a number of relatively small like characters in a pattern that presents a filled-in outline of the character. Each of the small like characters are printed by a thermographic process to provide a character which protrudes slightly from the media surface thus providing tactile feedback when the character is touched or traced with a finger.

Abstract: An improved printing support and method for use in a conventional dry lettering printing machine of the type having a print station, a rotatable printing support having print characters thereon, and means for causing the machine to execute a print cycle which includes providing a color carrying ribbon and image carrying tape at the print station, aligning the ribbon, tape, and a selected print character at the print station for printing, exerting a printing force at the print station, and reciprocating the tape cartridge to advance the tape and ribbon to print the next character at the print station. The improvement comprises inverting the print characters relative to a readable orientation so that when the characters are printed on a first tape surface and the tape is inverted, the characters appear in the correct sequence and orientation when viewed through the tape from a second tape surface opposite the first. The tape will thus be readable when inverted and placed on the underside of a transparent sheet.

Abstract: A device for monitoring and compensating for changes in the flight time of the print hammers of impact printers is disclosed. The flight time of the respectively monitored hammer is calculated from the elapsed time between the moment of firing of a hammer and the moment of impact of the print type carrier against the impact platen. In order to ensure automatic self-adjustment of all print hammers in predetermined test cycles, without the actual printing process itself being affected, and without there being any test imprints on the record carrier, the print type carrier includes, in addition to the standard print types, an additional test type. The impact surface area of the test type is large enough such that no visible imprint is made upon its impact on the record carrier because of the low impact pressure.

Abstract: Mechanisms are disclosed for modifying conventional single element and typebar typewriters, having character-for-character correction systems, with automatic backspacing or non-backspacing, and non-forward spacing, after obliteration, to provide an additional operational mode whereby character-for-character correction can be achieved with automatic forward spacing, after each obliteration, thereby to provide simplified word obliteration.

Abstract: A method and apparatus for correction of non-impact printed material which is formed by depositing a thermoplastic marking material on the print sheet. The method and apparatus uses a correction tape or ribbon comprising a substrate which carries a pressure transferable pigmented material on one face. The correction ribbon is positioned between the erroneously printed character and a correction device which is actuated to produce sufficient pressure to move the correction ribbon into intimate contact with the erroneously printed character, and the pigmented material is transferred selectively only to the character area to cover the erroneously printed character, so that the correct character can then be printed. In an alternate embodiment, the correction device is actuated concurrently with a backspace operation.

Abstract: A printing apparatus of the type having a printing station, a printing force exerting and resisting means, an image carrier and a font element with a raised character and a tape-ribbon cartridge therefor. The improvement of the present invention relates to an improved device for exerting a printing force and an improved tape-ribbon cartridge for supplying tape and ribbon to the printing station and for guiding and supporting the font element into printing alignment.

Abstract: An error correction system for a typewriter in which a silent type action with a blank type face is operatively connected and synchronized to initiate a backspace action and elevate and feed an error correction ribbon in advance of the striking of the blank type face against the space wherein an error was printed. Thus, to obliterate an error and type in a correct character, an operator need only perform two operations; depress the error key and the correct character key. Further, in accordance with the invention, the error key may be further depressed to a repeat position whereby a series of characters may be obliterated automatically.