Print control system for high speed printers

Claim 2

In combination with a high speed printer having a character pulse generator for producing character pulses at first intervals determined by the intervals between arrival of a series of characters in printing position, memory means for storing a sequence of character signals representing the characters in a line to be printed, means responsive to each character pulse for scanning said memory means and producing a sequence of binary signals each determining whether or not a character is to be printed in a different column following that character pulse, means for sequentially registering said sequences, timing signal generating means responsive to said character pulses for alternately producing a first or a second timing pulse following each memory scan, an image forming device for each binary signal in said sequence, and means controlled by said registering means and said timing signal generating meaNs for energizing each of said image forming devices for a time determined by said timing pulses when said registering means is storing a binary signal indicating that a character is to be printed by that image forming device and one of said timing signals is present.

Claim 3

In a high speed printer comprising means for producing character pulses at intervals t1 and a series of printing means, each actuable to print characters in response to energy applied at a substantially constant rate for an interval t2, where t2 is greater than t1, means for alternately producing first and second overlapping timing signals each having a duration t2, means for registering a first or a second signal for each image forming device following each character pulse, and means responsive to each first signal and either of said timing signals that is present for energizing the corresponding printing means for the duration of the timing signal that is present.

Claim 4

In a high speed printer comprising means for producing character pulses at intervals t1 and a series of printing means, each actuable to print characters in response to energy applied at a substantially constant rate for an interval t2, where t2 is greater than t1, means for alternately producing first and second overlapping timing signals each having a duration t2, means for registering a first or a second signal for each image forming device following each character pulse, and means responsive to each first signal and either of said timing signals that is present for energizing the corresponding printing means for the duration of the timing signal that is present.

Claim 5

In a high speed printer comprising memory means for storing a sequence of character signals each representing a character in a line to be printed, register means for storing a sequence of binary signals, one for each column in a line to be printed, each binary signal having a first or a second truth value according as a character is or is not to be printed in the associated column, means for producing a character pulse each time a character approaches printing position, means responsive to each character pulse for scanning said memory means and loading said register means with a sequence of binary signals each having a truth value determined by whether or not the character approaching printing position is to be printed in the corresponding column, means responsive to said character pulses for alternately producing first and second timing signals of equal duration greater than the intervals between said character pulses, printing means for each column in a line to be printed, and means controlled by said timing signals and said register means for actuating each printing means when the corresponding signal in said register means indicates that a character is to be printed for the interval of the timing signal that is present.

Claim 6

In a high speed printer comprising memory means for storing a sequence of character signals each representing a character in a line to be printed, register means for storing a sequence of binary signals, one for each column in a line to be printed, each binary signal having a first or a second truth value according as a character is or is not to be printed in the associated column, means for producing a character pulse each time a character approaches printing position, means responsive to each character pulse for scanning said memory means and loading said register means with a sequence of binary signals each having a truth value determined by whether or not the character approaching printing position is to be printed in the corresponding column, means responsive to said character pulses for alternately producing first and second timing signals of equal duration greater than the intervals between said character pulses, printing means for each column in a line to be printed, and means controlled by said timing signals and said register means for actuating each printing means when the corresponding signal in said register means indicates that a character is to be printed for the interval of the timing signal that is present.

Claim 7

In combination with a high speed printer having more than three image forming devices each requiring energization for an interval t1 and print signal registering means loaded at intervals t2 less than t1 with signals indicating whether or not each image forming device is to be energized in response to character pulses produced at intervals t2, timing signal generating means for alternately producing first and second timing signals of duration t1, and means controlled by said registering means and said timing signal generating means for activating each of said image forming devices for the duration of either of said timing signals that is present when said print signal registering means indicates that that image forming device is to be energized.

Claim 8

In combination with a high speed printer having more than three image forming devices each requiring energization for an interval t1 and print signal registering means loaded at intervals t2 less than t1 with signals indicating whether or not each image forming device is to be energized in response to character pulses produced at intervals t2, timing signal generating means for alternately producing first and second timing signals of duration t1, and means controlled by said registering means and said timing signal generating means for activating each of said image forming devices for the duration of either of said timing signals that is present when said print signal registering means indicates that that image forming device is to be energized.

Claim 9

In a high speed printer of the line at a time type having an image printing device for each column in a line to be printed and a character pulse generator for producing a character pulse each time a different character approaches printing position, memory means for storing a sequence of character signals, one for each column in the line to be printed, register means having a storage location for each column in the line to be printed, comparator means responsive to each character pulse for scanning said memory means and storing a sequence of signals in said register means each determining whether or not the character approaching printing position is or is not to be printed in a corresponding column, means for producing a first timing signal following every other character pulse, means for producing a second timing signal following every character pulse not followed by a first timing signal, and means controlled by said register means and said timing signals for energizing each image forming device for the duration of eaCh timing signal produced when the signal in the corresponding location of said register means indicates that the character coming into position is to be pritned.

Claim 10

In a high speed printer of the line at a time type having an image printing device for each column in a line to be printed and a character pulse generator for producing a character pulse each time a different character approaches printing position, memory means for storing a sequence of character signals, one for each column in the line to be printed, register means having a storage location for each column in the line to be printed, comparator means responsive to each character pulse for scanning said memory means and storing a sequence of signals in said register means each determining whether or not the character approaching printing position is or is not to be printed in a corresponding column, means for producing a first timing signal following every other character pulse, means for producing a second timing signal following every character pulse not followed by a first timing signal, and means controlled by said register means and said timing signals for energizing each image forming device for the duration of eaCh timing signal produced when the signal in the corresponding location of said register means indicates that the character coming into position is to be pritned.

Claim 11

The apparatus of claim 5, in which the duration of said first timing signals is equal to the duration of said second timing signals and greater than the interval between said character pulses.

Claim 12

The apparatus of claim 5, in which said means for energizing each image forming device comprises first and second latch means each enabled by a signal in the corresponding location of said register means indicating that the character coming into printing position is to be printed and set to energize the corresponding image device for an interval corresponding to the duration of a different one of said timing signals.

Claim 13

The apparatus of claim 7, in which the duration of said first timing signal is equal to the duration of said second timing signals and greater than the interval between said character pulses.

Claim 14

Apparatus for supplying printing energy to the image forming devices of a high speed printer having a character pulse generator producing character pulses at intervals t1 for intervals t2 longer than the intervals t1 between character pulses, comprising first and second latch means for each image forming device, a register for each image forming device set to a first state or a second state following each character pulse according as said image forming device is or is not to be energized, respectively, means responsive to said character pulses for alternately producing first and second timing signals having equal durations t2, and means controlled by each of said registers and by said timing signals when present for energizing the corresponding image forming device when the said register is in its first state for the duration of the timing signal that is present.

Claim 15

Apparatus for supplying printing energy to the image forming devices of a high speed printer having a character pulse generator producing character pulses at intervals t1 for intervals t2 longer than the intervals t1 between character pulses, comprising first and second latch means for each image forming device, a register for each image forming device set to a first state or a second state following each character pulse according as said image forming device is or is not to be energized, respectively, means responsive to said character pulses for alternately producing first and second timing signals having equal durations t2, and means controlled by each of said registers and by said timing signals when present for energizing the corresponding image forming device when the said register is in its first state for the duration of the timing signal that is present.

Claim 16

A print control system for line printers having a line memory adapted to be loaded with digital signals representing the characters to be printed on a line and means for moving a font of characters past each of a bank of image forming devices, one for each column in a line to be printed, comprising means for producing a character pulse each time a different character approaches printing position, means responsive to each character pulse for searching the memory for the character then approaching printing position, a first register, means responsive to each character pulse for loading said first register with a print signal for each column in which the associated character is to be printed, means responsive to each character pulse for detecting the parity of the character pulse in a predetermined sequence, a first bank of latches, one for each image forming device, a second bank of latches, one for each image forming device, means responsive to each character pulse and to said parity detecting means for producing a first or a second timing pulse for each character pulse in accordance with the parity of that character pulse, means responsive to said first timing pulse for actuating said first bank of latches to a first state or a second state in accordance with the contents of said first register to set the corresponding latch of said first bank of latches to its first state for the interval of said first pulse when the corresponding character print signal is present in said first register, means responsive to said second timing pulse for actuating said second bank of latches to a first state or a second state in accordance with the contents of said first register to set the corresponding latch of said second bank to its first state for the interval of said second pulse when the corresponding character print signal is present in said first register, and means controlled by said banks of latches in their first states for energizing said image forming devices.

Claim 17

A print control system for line printers having a line memory adapted to be loaded with digital signals representing the characters to be printed on a line and means for moving a font of characters past each of a bank of image forming devices, one for each column in a line to be printed, comprising means for producing a character pulse each time a different character approaches printing position, means responsive to each character pulse for searching the memory for the character then approaching printing position, a first register, means responsive to each character pulse for loading said first register with a print signal for each column in which the associated character is to be printed, means responsive to each character pulse for detecting the parity of the character pulse in a predetermined sequence, a first bank of latches, one for each image forming device, a second bank of latches, one for each image forming device, means responsive to each character pulse and to said parity detecting means for producing a first or a second timing pulse for each character pulse in accordance with the parity of that character pulse, means responsive to said first timing pulse for actuating said first bank of latches to a first state or a second state in accordance with the contents of said first register to set the corresponding latch of said first bank of latches to its first state for the interval of said first pulse when the corresponding character print signal is present in said first register, means responsive to said second timing pulse for actuating said second bank of latches to a first state or a second state in accordance with the contents of said first register to set the corresponding latch of said second bank to its first state for the interval of said second pulse when the corresponding character print signal is present in said first register, and means controlled by said banks of latches in their first states for energizing said image forming devices.

Claim 18

The apparatus of claim 10, in which said timing pulses are of equal duration greater than the intervals between character pulses.

Claim 19

In a high speed printer haviNg the capacity to print in more than three columns, means for producing character pulses, a register having the capacity to store a signal for each column to be printed, means for loading said register at each character pulse with signals indicating whether or not the corresponding character is to be printed in each column, first and second timing pulse generators each operable to produce a timing signal having a predetermined duration longer than the interval between character pulses, said timing pulses overlapping, first and second latch means, an image forming device for each column to be printed, and means controlled by said timing pulse generators, said latch means, and said register for energizing each image forming device each time a corresponding signal in said register indicates that a character is to be printed when a timing signal is produced for the duration of the timing signal.

Claim 20

In a high speed printer haviNg the capacity to print in more than three columns, means for producing character pulses, a register having the capacity to store a signal for each column to be printed, means for loading said register at each character pulse with signals indicating whether or not the corresponding character is to be printed in each column, first and second timing pulse generators each operable to produce a timing signal having a predetermined duration longer than the interval between character pulses, said timing pulses overlapping, first and second latch means, an image forming device for each column to be printed, and means controlled by said timing pulse generators, said latch means, and said register for energizing each image forming device each time a corresponding signal in said register indicates that a character is to be printed when a timing signal is produced for the duration of the timing signal.