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US4086601A Expired / Lapsed US ⏱️ 0.0 years remaining

Sequential ink jet printing system with variable number of guard drops

Assignee: International Business Machines Corp
•
Filing: 1976-05-24
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Granted: 1978-04-25
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Expires: 1996-05-24
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Abstract

Abstract Insertion of guard drops on a variable basis within a drop segment of an ink jet raster has been found to be highly successful in producing quality printing. A typical sequence is PgPgPgPggPgggPPgP <- time WHERE P designates a printed drop and g a guard drop. The drop on the right is the leading drop of the segment.

Inventors

  • 👤 Gary L. Fillmore
  • 👤 James D. Hill
  • 👤 William F. Robinson
  • 👤 Thomas H. Williams

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 00:06
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/075

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 73 words
Ink jet printing apparatus having means for generating and directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in drop printing sequences to form characters on said record medium; and drop control means for producing in each drop printing sequence a sequence of print drops and guard drops wherein a variable number of guard drops is interposed between successive pairs of print drops.
Claim 2
Dependent Claim 73 words
Ink jet printing apparatus having means for generating and directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in drop printing sequences to form characters on said record medium; and drop control means for producing in each drop printing sequence a sequence of print drops and guard drops wherein a variable number of guard drops is interposed between successive pairs of print drops.
Claim 3
Dependent Claim 86 words
The apparatus of claim 1 wherein each printing sequence comprises at least first (1), second (2), third (3), fourth (4), fifth (5) and succeeding print drops and wherein: said drop control means is operable in a "1032" mode to insert one guard drop between drops (1) and (2), no guard drops between drops (2) and (3), three guard drops between drops (3) and (4), two guard drops between drops (4) and (5) and one guard drop between each succeeding pair of drops beginning with drop (5).
Claim 4
Dependent Claim 89 words
Ink jet printing apparatus having means for generating and directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in drop printing sequences to form characters on said record medium; and drop control means for producing in each drop printing sequence a sequence of print drops and guard drops wherein the first and second print drops are force merged and wherein a variable number of guard drops, or zero guard drops, it interposed between each successive pair of print drops.
Claim 5
Dependent Claim 89 words
Ink jet printing apparatus having means for generating and directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in drop printing sequences to form characters on said record medium; and drop control means for producing in each drop printing sequence a sequence of print drops and guard drops wherein the first and second print drops are force merged and wherein a variable number of guard drops, or zero guard drops, it interposed between each successive pair of print drops.
Claim 6
Dependent Claim 27 words
The apparatus of claim 3 wherein said drop control means incorporates means for inserting a guard drop between the first and second print drops to enhance merging.
Claim 7
Dependent Claim 55 words
Ink jet printing apparatus having means for directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in segments to form characters on said record medium; and drop control means for producing in said segments sequences of ink drops including a variable number of guard drops.
Claim 8
Dependent Claim 55 words
Ink jet printing apparatus having means for directing ink drops toward a record medium for printing on a selective basis, comprising: means for grouping said drops in segments to form characters on said record medium; and drop control means for producing in said segments sequences of ink drops including a variable number of guard drops.
Claim 9
Dependent Claim 30 words
The apparatus of claim 5 further comprising: insert control logic incorporated in said drop control means for controlling the variable number of guard drops to be inserted in said segments.
Claim 10
Dependent Claim 30 words
The apparatus of claim 5 further comprising: black segment insert logic incorporated in said drop control means for controlling the number of guard drops in a black segment of drops.
Claim 11
Dependent Claim 55 words
The apparatus of claim 7 further comprising: aerodynamics correction table look-up logic providing output signals to said black segment insert logic indicative of variable numbers of guard drops required in black segments, and wherein said black segment logic is operable in response to said output signals to control production of guard drops in black segments.
Claim 12
Dependent Claim 33 words
The apparatus of claim 5 further comprising: a gutter for non-print drops; and wherein said drop control means produce sequences of print drops, continuous gutter drops and a variable number of guard drops.
Claim 13
Dependent Claim 54 words
The apparatus of claim 9 wherein said gutter drop and said guard drops are related by the ratio of about 2 guard drops for each 3 gutter drops such that for a white segment the relation of the number of gutter drops plus guard drops divided by gutter drops is about 1.5 to 2.
Claim 14
Dependent Claim 30 words
The apparatus of claim 10 which further comprises means for inserting guard drops in short white segments to cause the total uncharged drops to total five between black printed segments.

References Cited (Backward Citations)

US3596275A Cited
US3562757A Cited
US3833910A Cited
US3828354A Cited
US3846800A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-04-24 1981-10-24 1982-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-04-24 1985-10-24 1986-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-04-24 1989-10-24 1990-04-25 $7700.00 Window Closed / Lapsed

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