Line printer time shared electronics

Claim 2

A time shared electronic system for selectively driving a plurality of impact hammers of a rotary type multi-column impact printer with the hammers operatively associated with a print-drum rotationally supported for rotation about its axis having a font of characters engraved on its periphery the characters arranged in an array of columns and rows, the plurality of print hammers disposed in spatial one to one correspondence with the characters of a row when passing a print-ready position, the print hammers also movably supported for selectively striking a recording medium when disposed between the print hammers and the corresponding engraved characters, said time-shared electronic system comprising: a. data shift-register means for receiving a coded information to be printed on the recording medium; b. shift-register means coupled to said data shift-register means for receiving bit by bit and character by character the coded information shifted out of said data shift-register means and reapplying them bit by bit and character by character to said shift-register means; c. drum character line-counter means responsive to the rotating print drum as each row of characters thereon reaches printready position for identifying the row of characters on the print drum that is in print-ready position for printing on the recOrding medium; d. and comparator means coupled to said shift-register means and to said drum character line-counter means for comparing the coded information in said shift-register means with the coded information in said drum character line-counter means.

Claim 3

The time-shared electronic system as recited in claim 1 wherein said data shift-register means, said shift-register means, said drum character line-counter means and said comparator means statically store the coded information.

Claim 4

A time-shared electronics system as recited in claim 2 including column selector means coupled to said data register means and to said comparator means for selecting the column of a row in print-ready position when a match is found between the coded information in said shift-register means and said drum character line-counter means.

Claim 5

A time-shared electronic system as recited in claim 3 including first storage means for storing the identity of the column selected by said column selector means.

Claim 6

A time-shared electronic system as recited in claim 1 wherein all of the coded information in said data shift-register means to be printed on the recording medium are shifted bit by bit and character by character once through said shift-register means during a time interval equal to a time interval of rotation of the drum from one row of type to an adjacent row of type on the drum.

Claim 7

A time-shared electronic system as recited in claim 5 wherein all of the characters of a line to be printed on the recording medium in said data shift-register means are shifted through said shift-register means during one complete revolution of the print-drum for as many times as there are rows of characters on the print-drum.

Claim 8

A time-shared electronic system as recited in claim 6 including first magnetic signal generating means coupled to said drum character line-counter means for generating electronic timing signals each time that a row of characters passes by the print-ready position.

Claim 9

A time shared electronic system as recited in claim 7 including second magnetic signal generating means coupled to said drum character line counter means for producing an electronic reset signal to reset said drum character line counter means to zero each time a complete revolution of the print-drum occurs relative to the print-ready position and wherein the information in said drum character line counter means corresponds at any instant to the information engraved in the row of type on the print-drum in print-ready position during the same instant and wherein the corresponding information in said drum character line-counter means and the engraved row of type at any instant is in binary form in said drum character line-counter means and in decimal form in the engraved row of type on the print drum.

Claim 10

A rotary type multi-column impact printer comprising: a. a print-drum rotationally supported for rotation about its axis having a font of characters engraved on its periphery arranged in an array of columns and rows; b. a plurality of print-hammers disposed in spatial one to one correspondence with the characters of a row when passing a print-ready position, said print-hammers movably supported for selectively striking a recording medium when disposed between said print-hammers and said corresponding engraved characters; c. first flip-flop shift-register means for receiving a line of coded information for printing on the recording medium; d. second flip-flop shift-register means coupled to said first flip-flop shift-register means for serially receiving coded information from said first register means, serially shifting the coded information through said second shift-register means, and serially applying the coded information directly back into said first shift-register means; e. first flip-flop character line-counter means responsive to the row position of the characters relative to said print-hammers position, for identifying the row of characters on the print-drum that is in print-reAdy position for printing on the recording medium; f. comparator means coupled to said second flip-flop shift-register means and to said first flip-flop character line-counter means for comparing the coded information on said second flip-flop shift-register means with the code information in said first flip-flop character line-counter means; g. and first flip-flop ring-counter means responsive to said first flip-flop shift-register means for identifying the column of a row of characters in print-ready position, when a match is found between said second flip-flop shift-register means and said first flip-flop character line-counter means.

Claim 11

A rotary type multi-column impact printer comprising: a. a print-drum rotationally supported for rotation about its axis having a font of characters engraved on its periphery arranged in an array of columns and rows; b. a plurality of print-hammers disposed in spatial one to one correspondence with the characters of a row when passing a print-ready position, said print-hammers movably supported for selectively striking a recording medium when disposed between said print-hammers and said corresponding engraved characters; c. first flip-flop shift-register means for receiving a line of coded information for printing on the recording medium; d. second flip-flop shift-register means coupled to said first flip-flop shift-register means for serially receiving coded information from said first register means, serially shifting the coded information through said second shift-register means, and serially applying the coded information directly back into said first shift-register means; e. first flip-flop character line-counter means responsive to the row position of the characters relative to said print-hammers position, for identifying the row of characters on the print-drum that is in print-reAdy position for printing on the recording medium; f. comparator means coupled to said second flip-flop shift-register means and to said first flip-flop character line-counter means for comparing the coded information on said second flip-flop shift-register means with the code information in said first flip-flop character line-counter means; g. and first flip-flop ring-counter means responsive to said first flip-flop shift-register means for identifying the column of a row of characters in print-ready position, when a match is found between said second flip-flop shift-register means and said first flip-flop character line-counter means.

Claim 12

A rotary type multi-column impact printer as recited in claim 9 wherein said flip-flop ring-counter means is delayed one bit from the input coded information.

Claim 13

A rotary type multi-column impact printer as recited in claim 9 including first magnetic signal generating means coupled to said first flip-flop character line-counter means for generating electronic timing signals whenever a row of characters on the print-drum passes the print-ready position, second magnetic signal generating means coupled to said first flip-flop character line-counter means for producing an electronic reset signal to reset said first character line-counter means to an initial state whenever a complete revolution of the print-drum occurs relative to the print-ready position, and first reset flip-flop means responsive to said first magnetic signal generating means for dividing every two signals generated by said first magnetic signal generating means into one signal for incrementing said first flip-flop character line-counter means and another trigger signal which is the complement of said one signal.

Claim 14

A rotary type multi-column impact printer as recited in claim 15 wherein said hammer magnet driver means are comprised of a plurality of magnet driver flip-flop means coupled each to each to said column selector NAND gate means for selectively storing the column identity selected by said selector means, and transistor switch-means coupled each to each to said magnet driver flip-flop means and to said hammer magnet means for selectively switching said hammer magnet means to the on-state.

Claim 15

A rotary type multi-column impact printer as recited in claim 11 further including start flip-flop means coupled to said first reset flip-flop means and responsive to externally generated start signals for generating a start print cycle signal.

Claim 16

A rotary type multi-column impact printer as recited in claim 12 further including control flip-flop means coupled to said start flip-flop means and to said first reset flip-flop means for synchronizing the externally generated start signals to occur synchronously with a timing pulse.

Claim 17

A rotary type multi-column impact printer as recited in claim 12 further including AND gate means coupled to said control flip-flop means, to said first reset flip-flop means and to said comparator means for generating a signal when a match is obtained between the coded information in said second flip-flop shift-register means and the information in said first flip-flop character line-counter means, coincidentally with the application of said trigger signal and a sync signal to the input terminals of said AND gate means.

Claim 18

A rotary type multi-column impact printer as recited in claim 9 further including column selector means coupled to said first flip-flop ring-counter means and to said comparator means for selecting the column of a row of characters in print-ready position when a match is found between the coded information in said second flip-flop shift-register means and said first flip-flop character line-counter means, hammer magnet means operatively associated with said plurality of print-hammers for causing said plurality of print-hammers to selectively strike the recording medium when disposed between said print-hammers and said corresponding engraved characters, and hammer magnet driver means coupled to said column selector means and to said hammer magnet means for selectively energizing said hammer magnet means.

Claim 19

A rotary type multi-column impact printer as recited in claim 15 wherein said column selector means is comprised of a plurality of column selector NAND gate means each having at least three input terminals adapted to receive an (H) signal on one of its first input terminal, a (Qn) signal on its second input terminal and a (Qn) signal on its third input terminaL.

Claim 20

A rotary type multi-column impact printer as recited in claim 16 wherein there are at least twelve column selector NAND gate means and the (Qn, Qn) signal associated with each NAND gate are as follows: NAND Gate Identity Pattern of Qn Qn Signals 1 Q1 Q2 2 Q2 Q3 3 Q3 Q4 4 Q4 Q5 5 Q5 Q6 6 Q6 Q7 7 Q1 Q7 8 Q1 Q2 9 Q2 Q3 10 Q3 Q4 11 Q4 Q5 12 Q5 Q6

Claim 21

A rotary type multi-column printer as recited in claim 9 wherein the coded information that may appear in said first flip-flop character line-counter means corresponding to the characters engraved on said print wheel has the following corresponding code: First Flip-Flop Character Print Drum Character Line Counter Code and Row Number 0 0 0 0 0 0 0 0 1 1 0 0 1 0 2 0 0 1 1 3 0 1 0 0 4 0 1 0 1 5 0 1 1 0 6 0 1 1 1 7 1 0 0 0 8 1 0 0 1 9 1 1 1 1 Blank