Lateral position control means for data printer heads

Claim 2

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading electrical pulse signal train when said printing means is moving in a first direction and comprising a lagging electrical pulse signal train when said printing means is moving in a second direction, respectively, said second electrical pulse signal train comprising a lagging electrical pulse signal train when said printing means is moving in said first direction and comprising a leading electrical pulse signal train when said printing means is moving in said second direction, respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic level of a pulse in the leading electrical pulse signal train with a transition event in the logic level of the corresponding pulse in the lagging electrical pulse signal train, said transition event being a change from the particular type of logic state the existing in the lagging electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of reversal of the direction of printing.

Claim 3

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and second directions respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic state of a pulse in the lagging electrical pulse signal train with a transition event in the logic state of the corresponding pulse in the leading electrical pulse signal train, the transition event being a change from the same type of logic state then existing in the leading electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of any change in the direction of printing.

Claim 4

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and second directions respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic state of a pulse in the lagging electrical pulse signal train with a transition event in the logic state of the corresponding pulse in the leading electrical pulse signal train, the transition event being a change from the same type of logic state then existing in the leading electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of any change in the direction of printing.

Claim 5

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and second directions, respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic level of a pulse in the leading electrical pulse signal train with a transition event in the logic level of the corresponding pulse in the lagging electrical pulse signal train, said transition event being a change from the particular type of logic state then existing in the lagging electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of reversal of the direction of printing, said comparison means being conditioned to determine the instantaneous position of the printing means at a particular location as a function of printing movement direction and reversals of direction by producing from said first and second electrical pulse signal trains a first interim pulse series whose pulses indicate transitions in logic state from a low to a high level in the first electrical pulse signal train, by producing a second interim pulse series whose pulses indicate transitions in logic state from a high to low level in the first electrical pulse signal train, by producing a third interim pulse series representing the logic level condition of the second electrical pulse signal train at the times when pulses occur in the second interim pulse series, and by producing a fourth interim pulse series representing comparison of said third interim pulse series with both said first and said second interim pulse series.

Claim 6

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and second directions, respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic level of a pulse in the leading electrical pulse signal train with a transition event in the logic level of the corresponding pulse in the lagging electrical pulse signal train, said transition event being a change from the particular type of logic state then existing in the lagging electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of reversal of the direction of printing, said comparison means being conditioned to determine the instantaneous position of the printing means at a particular location as a function of printing movement direction and reversals of direction by producing from said first and second electrical pulse signal trains a first interim pulse series whose pulses indicate transitions in logic state from a low to a high level in the first electrical pulse signal train, by producing a second interim pulse series whose pulses indicate transitions in logic state from a high to low level in the first electrical pulse signal train, by producing a third interim pulse series representing the logic level condition of the second electrical pulse signal train at the times when pulses occur in the second interim pulse series, and by producing a fourth interim pulse series representing comparison of said third interim pulse series with both said first and said second interim pulse series.

Claim 7

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and said second directions respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic state of a pulse in the lagging electrical pulse signal train with a transition event in the logic state of the corresponding pulse in the leading electrical pulse signal train, the transition event being a change from the same type of logic state then existing in the leading electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of any change in the direction of printing, said comparison means being conditioned to determine the instantaneous position of the printing means at a particular location as a function of printing movement direction and reversals of direction by producing from said first and second electrical signal trains a first interim pulse series whose pulses indicate transitions in logic state from a low to a high level in the first electrical pulse signal train, by producing a second interim pulse series whose pulses indicate transitions in logic state from a high to a low level in the first electrical pulse signal train, by producing a third interim pulse series representing the logic level condition of the second electrical pulse signal train at the times when pulses occur in the second interim pulse series, and by producing a fourth interim pulse series representing comparison of said third interim pulse series with both said first and said second interim pulse series.

Claim 8

A data printing machine of the type having laterally movable printing means for selectively printing alphanumeric characters on a printing surface and having driving means for moving said printing means along a lateral path so that characters may be printed in horizontal rows, said printing machine further having an encoder means coupled to be actuated in accordance with the lateral movement of said printing means so as to produce first and second electrical pulse signal trains embodying information indicative of the position of said printing means along said lateral path, said electrical pulse signal trains having substantially the same electrical characteristics but being offset from one another by a known phase difference, said first electrical pulse signal train comprising a leading and a lagging electrical pulse signal train when said printing means is moving in a first and a second direction respectively, said second electrical pulse signal train comprising said lagging and said leading electrical pulse signal trains when said printing means is moving in said first and said second directions respectively, said printing machine further comprising: means for electrically decoding the first and second electrical pulse signal trains produced by the encoder means so as to obtain early and accurate indications whenever the printing means reverses its direction of motion along the path of its lateral travel, said means for electrically decoding comprising comparison means coupled to receive said first and second electrical pulse signal trains and conditioned to detect the instantaneous logic level state existing in the leading electrical pulse signal train in relation to the event of a transition in the logic level state of the lagging electrical pulse signal train, to thereby determine at the earliest instant any change in the direction of motion of the printing means from the direction of previous movement, said comparison means being conditioned to determine the direction of printing by comparing the logic state of a pulse in the lagging electrical pulse signal train with a transition event in the logic state of the corresponding pulse in the leading electrical pulse signal train, the transition event being a change from the same type of logic state then existing in the leading electrical pulse signal train to the opposite type of logic state, in order to obtain an early indication of any change in the direction of printing, said comparison means being conditioned to determine the instantaneous position of the printing means at a particular location as a function of printing movement direction and reversals of direction by producing from said first and second electrical signal trains a first interim pulse series whose pulses indicate transitions in logic state from a low to a high level in the first electrical pulse signal train, by producing a second interim pulse series whose pulses indicate transitions in logic state from a high to a low level in the first electrical pulse signal train, by producing a third interim pulse series representing the logic level condition of the second electrical pulse signal train at the times when pulses occur in the second interim pulse series, and by producing a fourth interim pulse series representing comparison of said third interim pulse series with both said first and said second interim pulse series.