Patent US4638325A successfully refreshed from Google Patents.
US4638325A
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US
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Ink jet filament length and stimulation amplitude assessment system
Assignee: Eastman Kodak Co
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Filing: 1985-09-09
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Granted: 1987-01-20
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Expires: 2005-09-09
Abstract
Abstract The length of an ink jet filament as a function of stimulation amplitude is measured in an ink jet printing apparatus by locating a narrow charging electrode near the drop break-off point of the ink jet filament, varying the stimulation amplitude to vary the filament length, and measuring the amount of charge imparted to the ink drops as the filament length is changed. Stimulation amplitude is automatically adjusted by as a function of the measured charge.
Inventors
- 👤 John M. Schneider
- 👤 Michael J. Piatt
- 👤 Mark E. Brown
- 👤 Mark C. Bowers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:21
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/115
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
108 words
A method for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterised by: locating a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, adjacent the ink jet filament and applying a charging voltage to the narrow electrode; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the magnitude of the charge imparted to the ink drops by the narrow charging electrode; and sensing the length of the ink jet filament as a function of the detected charge.
Claim 2
Independent Claim
108 words
A method for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterised by: locating a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, adjacent the ink jet filament and applying a charging voltage to the narrow electrode; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the magnitude of the charge imparted to the ink drops by the narrow charging electrode; and sensing the length of the ink jet filament as a function of the detected charge.
Claim 3
Dependent Claim
48 words
The method for sensing the length of an ink jet filament claimed in claim 1, further characterized by: the charging voltage being a low voltage insufficient to deflect a charged ink drop into a catcher; and the charge being detected by an electrometer located in a nose cup.
Claim 4
Dependent Claim
29 words
The method for sensing the length of the ink jet filament claimed in claim 2, further characterized by: the narrow charging electrode being located opposite a planar charging electrode.
Claim 5
Dependent Claim
35 words
The method of sensing the length of an ink jet filament claimed in claim 1, further characterized by: said narrow charging electrode also functioning as a normal charging electrode for the ink jet print head.
Claim 6
Dependent Claim
45 words
The method for sensing the length of an ink jet filament claimed in claim 4, further characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher, and the charge being detected by an electrometer located in the catcher.
Claim 7
Dependent Claim
55 words
The method for sensing the length of an ink jet filament claimed in claim 4, further characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher, and the charge being detected by means for sensing the height of impact of the deflected ink drops on the catcher face.
Claim 8
Independent Claim
129 words
A method for adjusting the amplitude of stimulation in a continuous ink jet printer, characterized by: locating a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, adjacent the ink jet filament and applying a charge voltage to the narrow electrode; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the amount of charge imparted to the ink drops by the narrow charging electrode; sensing the stimulation amplitude that produces the shortest ink jet filament by sensing a peak in the detected charge as the amplitude is varied; and setting the amplitude of the stimulation signal a predetermined amount below the amplitude effective to cause the shortest ink jet filament.
Claim 9
Independent Claim
129 words
A method for adjusting the amplitude of stimulation in a continuous ink jet printer, characterized by: locating a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, adjacent the ink jet filament and applying a charge voltage to the narrow electrode; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the amount of charge imparted to the ink drops by the narrow charging electrode; sensing the stimulation amplitude that produces the shortest ink jet filament by sensing a peak in the detected charge as the amplitude is varied; and setting the amplitude of the stimulation signal a predetermined amount below the amplitude effective to cause the shortest ink jet filament.
Claim 10
Dependent Claim
56 words
The method for adjusting the amplitude of stimulation in a continuous ink jet printer claimed in claim 7, characterized by: the charging voltage being a low voltage insufficient to deflect a charged ink drop into a catcher; and the charge being detected by an electrometer located in a nose cup at a storage and start-up location.
Claim 11
Dependent Claim
31 words
The method for adjusting the amplitude of stimulation in a continuous ink jet printer claimed in claim 8, characterized by: the narrow charging electrode being located opposite a planar charging electrode.
Claim 12
Dependent Claim
36 words
The method for adjusting the amplitude of stimulation in a continuous ink jet printer claimed in claim 7, characterized by: said narrow charging electrode also functioning as a normal charging electrode for the ink jet printer.
Claim 13
Dependent Claim
47 words
The method for adjusting the amplitude of stimulation in a continuous ink jet printer claimed in claim 10, characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher, and the charge being detected by an electrometer located in the catcher.
Claim 14
Dependent Claim
55 words
The method for adjusting the amplitude of stimulation in a continuous ink jet printer claimed in claim 10, characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher, and the charge being detected by means for sensing the height of impact of the drops on a catcher face.
Claim 15
Dependent Claim
95 words
Apparatus for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: a narrow drop charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, located adjacent the ink jet filament; means for applying a charging voltage to the narrow drop charging electrode; means for applying a stimulation signal of varying amplitude to the ink jet head; and means for detecting the amount of charge imparted to the ink drops by the narrow charging electrode.
Claim 16
Dependent Claim
95 words
Apparatus for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: a narrow drop charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, located adjacent the ink jet filament; means for applying a charging voltage to the narrow drop charging electrode; means for applying a stimulation signal of varying amplitude to the ink jet head; and means for detecting the amount of charge imparted to the ink drops by the narrow charging electrode.
Claim 17
Dependent Claim
58 words
The filament length sensing apparatus claimed in claim 13, further characterized by: said charging voltage being a low voltage insufficient to deflect the charged ink drops into a catcher; and said charge magnitude detecting means being an electrometer having a sensing electrode located in a nose cup at a storage and start-up station in the ink jet printer.
Claim 18
Dependent Claim
34 words
The filament length sensing apparatus claimed in claim 14, further characterized by: the ink jet print head having a planar charging electrode; and said narrow charging electrode being located opposite said planar charging electrode.
Claim 19
Dependent Claim
26 words
The filament length sensing apparatus claimed in claim 13, further characterized by: said narrow charging electrode being the normal charging electrode of the ink jet printer.
Claim 20
Dependent Claim
45 words
The filament length sensing apparatus claimed in claim 16, further characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher; and the means for detecting the amount of charge comprising an electrometer located in the ink jet catcher.
Claim 21
Dependent Claim
47 words
The filament length sensing apparatus claimed in claim 16, characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher; and said charge detecting means comprising means for sensing the height of impact of the ink drops on a catcher face.
Claim 22
Dependent Claim
116 words
Apparatus for adjusting stimulation amplitude in a continuous ink jet printer, characterized by: a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, located adjacent the ink jet filament; means for applying a charging voltage to the narrow charging electrode; means for varying the amplitude of the stimulation signal applied to the ink jet print head; means for detecting the amount of charge imparted to the ink drops by the narrow charging electrode; means for detecting the peak charge imparted to the ink drops; and means for setting the stimulation amplitude a predetermined amount below the amplitude producing the peak charge on the ink drops.
Claim 23
Dependent Claim
116 words
Apparatus for adjusting stimulation amplitude in a continuous ink jet printer, characterized by: a narrow charging electrode, extending less than or equal to one drop spacing in the direction of the ink jet filament, located adjacent the ink jet filament; means for applying a charging voltage to the narrow charging electrode; means for varying the amplitude of the stimulation signal applied to the ink jet print head; means for detecting the amount of charge imparted to the ink drops by the narrow charging electrode; means for detecting the peak charge imparted to the ink drops; and means for setting the stimulation amplitude a predetermined amount below the amplitude producing the peak charge on the ink drops.
Claim 24
Dependent Claim
58 words
The stimulation amplitude adjusting apparatus claimed in claim 19, further characterized by: said charging voltage being a low voltage insufficient to deflect the charged ink drops into a catcher; and said charge magnitude detecting means comprising an electrometer having a sensing electrode located in a nose cup at a storage and start-up station in the ink jet printer.
Claim 25
Dependent Claim
34 words
The stimulation amplitude adjustment apparatus claimed in claim 20, further characterized by: the ink jet print head having a planar charging electrode; and said narrow charging electrode being located opposite said planar charging electrode.
Claim 26
Dependent Claim
27 words
Stimulation amplitude adjustment apparatus as claimed in claim 19, further characterized by: said narrow charging electrode being the normal charging electrode of the ink jet printing apparatus.
Claim 27
Dependent Claim
45 words
Stimulation adjustment apparatus claimed in claim 22, further characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher; and said means for detecting the amount of charge imparted to the drops comprising an electrometer located in the catcher.
Claim 28
Dependent Claim
56 words
Stimulation amplitude adjusting apparatus claimed in claim 23, further characterized by: said charging voltage being a high voltage sufficient to deflect charged drops into a catcher; and said means for detecting the amount of charge imparted to the ink drops comprising means for sensing the height of impact of the ink drops on the catcher face.
Claim 29
Independent Claim
119 words
A method for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: locating a pair of narrow charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip adjacent the ink jet filament and applying charging voltages of opposite polarity to said narrow charging electrodes; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the magnitude of the charge imparted to the ink drops by the narrow charging electrode; and sensing the length of the ink jet filament as a function of the detected charge.
Claim 30
Independent Claim
119 words
A method for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: locating a pair of narrow charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip adjacent the ink jet filament and applying charging voltages of opposite polarity to said narrow charging electrodes; changing the amplitude of the stimulation signal to change the length of the ink jet filament; detecting the magnitude of the charge imparted to the ink drops by the narrow charging electrode; and sensing the length of the ink jet filament as a function of the detected charge.
Claim 31
Dependent Claim
54 words
The method for sensing the length of an ink jet filament claimed in claim 25, further characterized by: the charging voltages being of such a magnitude that ink drops that separate opposite said insulating strip receive a charge of zero volts, and sensing when the charge imparted to the ink drops is zero volts.
Claim 32
Independent Claim
123 words
A method for adjusting the amplitude of stimulation in a continuous ink jet printer characterized by: locating a pair of narrow charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip adjacent the ink jet filament and applying charging voltages of opposite polarity to said charging electrodes, said charging voltages being of such a magnitude that drops breaking off adjacent to said insulating strip receive a charge of zero volts; applying a stimulation signal to the ink jet print head; sensing the charge imparted to the ink drops; and adjusting the amplitude of the stimulation signal until a charge of zero volts is imparted to the ink drops.
Claim 33
Independent Claim
123 words
A method for adjusting the amplitude of stimulation in a continuous ink jet printer characterized by: locating a pair of narrow charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip adjacent the ink jet filament and applying charging voltages of opposite polarity to said charging electrodes, said charging voltages being of such a magnitude that drops breaking off adjacent to said insulating strip receive a charge of zero volts; applying a stimulation signal to the ink jet print head; sensing the charge imparted to the ink drops; and adjusting the amplitude of the stimulation signal until a charge of zero volts is imparted to the ink drops.
Claim 34
Dependent Claim
105 words
Apparatus for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: a pair of narrow drop charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip, located adjacent the ink jet filament; means for applying charging voltages of opposite polarity to said narrow drop charging electrodes; means for applying a stimulation signal of varying amplitude to the ink jet head; and means for detecting the amount of charge imparted to the ink drops by the narrow charging electrodes.
Claim 35
Dependent Claim
105 words
Apparatus for sensing the length of an ink jet filament in response to stimulation amplitude in a continuous ink jet printer, characterized by: a pair of narrow drop charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip, located adjacent the ink jet filament; means for applying charging voltages of opposite polarity to said narrow drop charging electrodes; means for applying a stimulation signal of varying amplitude to the ink jet head; and means for detecting the amount of charge imparted to the ink drops by the narrow charging electrodes.
Claim 36
Dependent Claim
35 words
The filament length sensing apparatus claimed in claim 28, further characterized by: said charging voltages being of such magnitude that zero volts are induced on ink drops that break off adjacent said narrow insulating strip.
Claim 37
Dependent Claim
130 words
Apparatus for adjusting filament length in a continuous ink jet printer, characterized by: a pair of narrow drop charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip located adjacent the ink jet filament at a predetermined distance from an orifice plate; means for applying charging voltages of opposite polarity to said charging electrodes, of such a magnitude that ink drops breaking off adjacent said insulating strip received a charge of zero volts; means for sensing the charge imparted to the ink drops; and means for adjusting the amplitude of the stimulation signal until a charge of zero volts is imparted to the ink drops, whereby the filament length is adjusted to said predetermined distance.
Claim 38
Dependent Claim
130 words
Apparatus for adjusting filament length in a continuous ink jet printer, characterized by: a pair of narrow drop charging electrodes, extending less than or equal to one drop spacing in the direction of the ink jet filament, separated by a thin insulating strip located adjacent the ink jet filament at a predetermined distance from an orifice plate; means for applying charging voltages of opposite polarity to said charging electrodes, of such a magnitude that ink drops breaking off adjacent said insulating strip received a charge of zero volts; means for sensing the charge imparted to the ink drops; and means for adjusting the amplitude of the stimulation signal until a charge of zero volts is imparted to the ink drops, whereby the filament length is adjusted to said predetermined distance.
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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) | 1990-01-19 | 1990-07-21 | 1991-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-19 | 1994-07-21 | 1995-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-19 | 1998-07-21 | 1999-01-20 | $7700.00 | Window Closed / Lapsed |