Automatic justifying typewriter having pitch changing and line spacing apparatus

In an automatic justifying typewriter wherein a printer includes a horizontally movable carriage for interchangeable mounting of single element print heads of variable type fonts, a rotatable platen provided for a print-out sheet which is selectively engaged by said single element print head, and a keyboard for producing coded electrical printing signals representative of printing and functional operations performed by said keyboard including characters, carriage return and index, the combination therewith comprising:

• horizontal stepping motor means coupled to said carriage and being operative to advance said single element print head in horizontal increments either for forward or reverse escapement, said horizontal stepping motor means including a horizontal stepping motor having an output shaft and horizontal drive means on the output shaft of said horizontal stepping motor,
• vertical stepping motor means coupled to said platen and operative to rotate said platen in vertical increments to index said print-out sheet,
• data source means for storing the coded electrical printing signals produced by said keyboard including processing means for producing a horizontal character spacing signal in a number of increments proportional to the width of each said character, said processing means being further operative to produce functional operation signals for word spacing after each word received, indexing and backspacing, each of said functional operation signals including a number of increments corresponding thereto,
• data entry means for successively applying in sequence one of said coded printing signals followed by at least one of said functional operation signals from said data source means,
• printer gate means responsive to said data entry means for selectively gating said coded printing signals from said data entry means to said printer,
• stepping motor gate means responsive to said data entry means for selectively gating said functional operation signals to one of said horizontal and vertical stepping motor means, said stepping motor gate means including counter means for storing signals corresponding to said increments of said horizontal character spacing signal and said functional operation signals, and
• control means coupled between said data entry means and said printer gate and stepping motor gate means to alternately gate said coded printing signals to said printer and said functional operation signals and character spacing signals to said stepping motor gate means respectively, said control means including means for actuating the print head to print a character followed by stepping said horizontal stepping motor means a predetermined number of horizontal increments corresponding to the number of increments identified by said character spacing signal and said functional operation signals in accordance with the content of said counter means.

In proportional printing apparatus including a printer having character printing means and printer control means for actuating said character printing means to impress selected characters on a print-out sheet or the like, the improvement comprising:

• coupling means including first gear means for providing horizontal relative movement between said character printing means and said print-out sheet,
• a stepping motor having second gear means attached to the output shaft thereof, said first and second gear means intermeshing at a plurality of positions for providing motion transfer therebetween at different ratios as between said positions,
• means for mounting said stepping motor for pivotal and axial movement,
• means for moving said stepping motor in said mounting means for selecting one of said intermeshing positions of said first and second gear means,
• a data source for selectively and successively producing coded printing control signals each corresponding to a particular character to be printed and coded spacing control signals including counts corresponding to a preselected horizontal space for each respective character to be printed,
• said printer control means being operatively associated with said character printing means and being responsive to each printing control signal to actuate said character printing means to print the said character identified thereby, and
• means responsive to each said spacing control signal for a character to actuate said stepping motor for effecting relative motion by said coupling means in increments identified by said counts of said spacing control signals and in accordance with the position of said selecting means.

In an automatic justifying typewriter wherein a printer includes a horizontally movable carriage for interchangeable mounting of single element print heads of variable type fonts, a rotatable platen provided for a print-out sheet which is selectively engaged by said single element print head, and a keyboard including encoding logic means for producing coded printing signals representative of printing and functional operations performed by said keyboard, the combination therewith comprising:

• horizontal stepping motor means coupled to said carriage and operative to advance said single element print head in horizontal increments either in forward or reverse escapement, said horizontal stepping motor means including a horizontal stepping motor having an output shaft, horizontal drive means on the output shaft of said horizontal stepping motor, and shift means to selectively position said horizontal stepping motor and said horizontal drive means for a plurality of pitch settings to conform the escapement distance of each step of said horizontal stepping motor means to the font size on said single element print head,
• said shift means including variable pitch transmission means coupled to said horizontal drive means, said variable pitch transmission means having a plurality of gear settings corresponding to said plurality of pitch settings cooperating with said shift means such that said horizontal drive means operates to engage one of said gear settings,
• horizontal stepping motor control means being operative to apply stepping pulses to said horizontal stepping motor means to control forward and reverse stepping of said horizontal stepping motor thereby to effect forward and reverse stepping escapement of said single element print head for a number of steps corresponding to the stepping pulses applied to said horizontal stepping motor means,
• vertical stepping motor means coupled to said platen and operative to rotate said platen in vertical increments to index said print-out sheet,
• vertical stepping motor control means being operative to apply stepping pulses to said vertical stepping motor means to control indexing of said platen for a number of steps corresponding to the stepping pulses applied to said vertical stepping motor means,
• data source means for storing said coded printing signals and including processing means for determining the space requirements of each said character, for producing a character spacing signal in a number of increments proportional to the width of each said character, and for producing functional operation signals including word spacing signals after each word received, a carriage return signal at the end of each line, indexing and backspacing signals,
• data entry means for successively applying one of said coded printing signals and functonal operation signals, followed by said character spacing signal and after each word signal followed by said word spacing signal sequentially from said data source means,
• printer gate means for selectively gating said coded printing signals from said data entry means to said printer, said coded printing signals being operative with said printer to print said character on said print-out sheet,
• stepping motor gate means for selectively gating said character and word spacing signals to said horizontal stepping motor control means and for selectively gating said functional operation signals to said vertical stepping motor control means, said stepping motor gate means including a step oscillator for generating a train of step pulses for energizing both said horizontal and vertical stepping motor control means and counter means responsive to said character spacing signal to control the number of times the said step oscillator energizes the said horizontal stepping motor control means, and
• control means between said data entry means, said printer gate means and said stepping motor gate means to alternately gate said coded printing signals to said printer and said functional operation signals and character and word spacing signals to said stepping motor gate means respectively to operate to print a character followed by stepping said horizontal stepping motor means a predetermined number of horizontal increments.