US4116567A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Printer synchronization control for shuttle having non-uniform velocity
Assignee: Oki Electric Industry Co Ltd
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Filing: 1976-12-22
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Granted: 1978-09-26
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Expires: 1996-12-22
Abstract
Abstract A printer synchronization control for maintaining columnar alignment of dots printed by a dot matrix printer including a shuttle wherein the relative velocity between the paper and shuttle is non-uniform. Plural print elements are mounted on the shuttle for printing dots at preselected positions on the paper. A particular row and column arrangement of the dots defines a character. A counter measures the relative velocity between the paper and shuttle over a period of time inversely proportional to the relative velocity. A second counter determines the time at which an actuator must be triggered to cause a print element to strike the paper at a preselected columnar position to maintain columnar alignment of the dots in a character. Means are provided for causing the print element to strike the paper at the preselected columnar position as a function of the second counter. A third counter may be provided to enable two or more sets of the print elements to be actuated in time-staggered fashion to minimize peak current drain.
Inventors
- 👤 Craig San Pietro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:21
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/485; B41J2/505; B41J2/5056; B41J25/00; B41J25/001; B41J25/006
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
128 words
In a dot matrix printer including a shuttle and plural print elements mounted thereon for printing dots at preselected positions on a paper, wherein the relative velocity between the paper and the shuttle is non-uniform and wherein each of the print elements strikes the paper a finite time Tflight after having been actuated, a printer synchronization control comprising: means for measuring the relative velocity between the paper and the shuttle over a period of time Tinc inversely proportional to the relative velocity; means for determining the time Tdec at which a print element must be actuated to strike the paper at a preselected columnar position; and means for causing the print element to strike the paper at said preselected position as a function of said time determining means.
Claim 2
Dependent Claim
128 words
In a dot matrix printer including a shuttle and plural print elements mounted thereon for printing dots at preselected positions on a paper, wherein the relative velocity between the paper and the shuttle is non-uniform and wherein each of the print elements strikes the paper a finite time Tflight after having been actuated, a printer synchronization control comprising: means for measuring the relative velocity between the paper and the shuttle over a period of time Tinc inversely proportional to the relative velocity; means for determining the time Tdec at which a print element must be actuated to strike the paper at a preselected columnar position; and means for causing the print element to strike the paper at said preselected position as a function of said time determining means.
Claim 3
Dependent Claim
49 words
A printer synchronization control in accordance with claim 1 wherein the time at which the print element must be triggered is determined by the relationship: Tdec = (N/2)Tinc - Tflight where N is an integer greater than 2Tflight/Tinc minimum and where Tinc minimum is the minimum value of Tinc.
Claim 4
Dependent Claim
39 words
A printer synchronization control in accordance with claim 1 wherein said measuring means includes a clock oscillator for generating pulses at a fixed frequency and a velocity counter for counting the clock pulses over the period of time Tinc.
Claim 5
Dependent Claim
52 words
A printer synchronization control in accordance with claim 3 wherein said time determining means includes a frequency divider circuit for dividing the frequency of the clock pulses by an integral multiple of one half, and a counter for counting the output of the frequency divider circuit over the interval of time Tdec.
Claim 6
Dependent Claim
175 words
In a dot matrix printer including a shuttle and plural print elements divisible into at least two sets mounted on the shuttle for printing dots at preselected positions on a paper, wherein the relative velocity between the paper and shuttle is non-uniform and wherein each of the print elements strikes the paper a finite time Tflight after having been actuated, a printer synchronization control comprising: means for measuring the relative velocity between the paper and shuttle over a period of time Tinc inversely proportional to the relative velocity; means for determining the time Tdec1 at which a first set of print elements must be triggered for the print elements to strike the paper at preselected columnar positions; means for determining the time Tdec2 at which a second set of print elements must be triggered for the print elements to strike the paper at preselected columnar positions; and means for causing the first and second sets of print elements to strike the paper in time-staggered fashion as a function of both of said time determining means.
Claim 7
Dependent Claim
175 words
In a dot matrix printer including a shuttle and plural print elements divisible into at least two sets mounted on the shuttle for printing dots at preselected positions on a paper, wherein the relative velocity between the paper and shuttle is non-uniform and wherein each of the print elements strikes the paper a finite time Tflight after having been actuated, a printer synchronization control comprising: means for measuring the relative velocity between the paper and shuttle over a period of time Tinc inversely proportional to the relative velocity; means for determining the time Tdec1 at which a first set of print elements must be triggered for the print elements to strike the paper at preselected columnar positions; means for determining the time Tdec2 at which a second set of print elements must be triggered for the print elements to strike the paper at preselected columnar positions; and means for causing the first and second sets of print elements to strike the paper in time-staggered fashion as a function of both of said time determining means.
Claim 8
Dependent Claim
82 words
A printer synchronization control in accordance with claim 5 wherein the time at which the first set of print elements must be triggered is determined by the relationship: Tdec1 = (N/2)Tinc - Tflight and wherein the time at which the second set of print elements must be triggered is determined by the relationship: Tdec2 = (N/2)Tinc - Tflight + T0 where N is an integer and T0 is an interval of time determined by the relative velocity between the paper and shuttle.
Claim 9
Dependent Claim
48 words
A printer synchronization control in accordance with claim 5 wherein said means for measuring the relative velocity between the paper and shuttle comprises a clock oscillator for generating clock pulses at a fixed frequency, and a velocity counter for counting the clock pulses during the time interval Tinc.
Claim 10
Dependent Claim
74 words
A printer synchronization control in accordance with claim 7 wherein said means for determining the times Tdec1 and Tdec2 comprises a frequency divider circuit for dividing the frequency of the clock pulses by an integral multiple of one half, a first counter for counting the output of said frequency divider circuit during the time interval Tdec1, and a second counter for counting the output of said frequency divider circuit during the time interval Tdec2.
Claim 11
Dependent Claim
26 words
A printer synchronization control in accordance with claim 6 wherein the interval of time T0 is equivalent to a fraction of the diameter of a dot.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |