Patent US4631550A successfully refreshed from Google Patents.
US4631550A
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Device and method for sensing the impact position of an ink jet on a surface of an ink catcher, in a continuous ink jet printer
Assignee: Eastman Kodak Co
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Filing: 1985-08-15
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Granted: 1986-12-23
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Expires: 2005-08-15
Abstract
Abstract Information relating to the impact position on a catcher face of a deflected ink jet is used to adjust various parameters of an ink jet printing system, such as the charge voltage, the time between orifice plate stimulation and drop charging, etc., or to check the occurrence of malfunctions such as crooked jets, misregistration between the charge plate and the jets, etc. According to the invention, means integral with the catcher cooperate with the ink flowing on the catcher face to vary an electrical property at said catcher face as a function of the portion of that face which is ink wetted. In one embodiment the jet impact position is derived from an electrical resistance measurement. In another embodiment this position is derived from a capacitance measurement.
Inventors
- 👤 Michael J. Piatt
- 👤 Mark E. Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:16
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/125; B41J2/17; B41J2/18; B41J2/185; B41J2002/1853
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
106 words
Device for sensing the impact position of an electrically conductive ink jet on the vertical face of an ink catcher extending generally parallel to the ink jet and forming part of the printing head of an ink jet printer, characterized by: (a) means integral with the catcher and associated with said catcher face so as to exhibit an electrical property varying as a function of the portion of the face which is wetted by the ink flowing downstream of the impact position of the jet and, (b) circuit means for sensing said electrical property and for deriving therefrom a signal representative of the jet impact position.
Claim 2
Dependent Claim
106 words
Device for sensing the impact position of an electrically conductive ink jet on the vertical face of an ink catcher extending generally parallel to the ink jet and forming part of the printing head of an ink jet printer, characterized by: (a) means integral with the catcher and associated with said catcher face so as to exhibit an electrical property varying as a function of the portion of the face which is wetted by the ink flowing downstream of the impact position of the jet and, (b) circuit means for sensing said electrical property and for deriving therefrom a signal representative of the jet impact position.
Claim 3
Dependent Claim
30 words
Device according to claim 1, characterized in that said circuit means is configured and connected to said integral means so as to sense the electrical impedance of said integral means.
Claim 4
Dependent Claim
74 words
Device according to claim 2, characterized in that said inegral means comprises an electrically conductive catcher face and a plurality of insulating means dividing the catcher face into a plurality of conductive areas, and in that said circuit means is configured and connected to these areas for detecting which insulating means are short-circuited by the ink flowing over the catcher face, so as to determine the particular area where the ink jet is impacting.
Claim 5
Dependent Claim
32 words
Device according to claim 3, characterized in that said insulating means are made of a low surface adhesion material for preventing a stationary ink bridge after the stream of ink has changed.
Claim 6
Dependent Claim
63 words
Device according to claim 2, characterized in that said integral means comprises a catcher face material exhibiting a surface resistivity greater than the one of a thin layer of ink flowing over the catcher surface and in that said circuit means derives, from a measurement of the total resistance of the ink-wetted catcher surface, an analog measurement of the ink jet impact position.
Claim 7
Dependent Claim
97 words
Device according to claim 2, characterized in that said integral means is comprised of an electrode embedded in the catcher and substantially parallel to the catcher face, an insulating material covering said catcher face so as to form a capacitor when a thin layer of conductive ink, forming a second electrode is flowing over that catcher face, and in that said circuit means is configured and electrically connected to the electrodes for measuring the capacitance of the capacitor and for deriving therefrom the surface of the ink layer electrode and the position of the ink jet impact.
Claim 8
Dependent Claim
36 words
Device according to claim 6, characterized in that said ink layer electrode is electrically connected to said circuit means through a metal pan forming one wall of a gutter collecting the ink impacting the catcher face.
Claim 9
Dependent Claim
65 words
Device according to any of claims 2 to 6, characterized in that said circuit means is comprised of a 555 integrated circuit mounted as a timer and delivering pulses at a frequency F=0.7 ((R x +2R 1 )C x ), R x and C x being respectively the jet impact position variable resistor or capacitor to be measured and R 1 being a reference resistance.
Claim 10
Independent Claim
91 words
A method for sensing the impact position of an ink jet on the vertical face of an ink catcher extending generally parallel to the ink jet and forming part of the printing head of an ink jet printer, comprising the steps of: (a) varying an electrical property at said catcher face as a function of the portion of that face which is wetted by the ink flowing downstream the impact position of the jet and, (b) sensing said electrical property and deriving therefrom a signal representative of the jet impact position.
Claim 11
Independent Claim
91 words
A method for sensing the impact position of an ink jet on the vertical face of an ink catcher extending generally parallel to the ink jet and forming part of the printing head of an ink jet printer, comprising the steps of: (a) varying an electrical property at said catcher face as a function of the portion of that face which is wetted by the ink flowing downstream the impact position of the jet and, (b) sensing said electrical property and deriving therefrom a signal representative of the jet impact position.
Claim 12
Dependent Claim
15 words
A method according to claim 9, wherein the variable electrical property is an electrical impedance.
Claim 13
Dependent Claim
15 words
A method according to claim 9, wherein the variable electrical property is an electrical capacitance.
Claim 14
Dependent Claim
103 words
A continuous ink jet printing apparatus, including means for adjusting the phase relations between the stimulation and charging of the ink jet, characterized by: means for sensing the impact of the ink jet on a vertical face of an ink catcher extending generally parallel to the ink jet to product an impact signal; means for generating and applying a narrow jet charging signal; means for shifting the phase of the narrow jet charging signal with respect to a stimulation signal; and means responsive to the impact signal for detecting the phase at which the ink jet impacts the face of the ink catcher.
Claim 15
Dependent Claim
103 words
A continuous ink jet printing apparatus, including means for adjusting the phase relations between the stimulation and charging of the ink jet, characterized by: means for sensing the impact of the ink jet on a vertical face of an ink catcher extending generally parallel to the ink jet to product an impact signal; means for generating and applying a narrow jet charging signal; means for shifting the phase of the narrow jet charging signal with respect to a stimulation signal; and means responsive to the impact signal for detecting the phase at which the ink jet impacts the face of the ink catcher.
Claim 16
Dependent Claim
60 words
The ink jet printing apparatus claimed in claim 12, characterized in that said means for sensing the impact of the ink jet on the face of the ink catcher, includes means for exhibiting a variable electrical property as a function of the portion of the face that is wetted by the ink and means for sensing the variable electrical property.
Claim 17
Independent Claim
101 words
A method for determining the proper phase relationship between the stimulation and charging of a ink jet in a continuous type ink jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet; characterized by the steps of: generating and applying a narrow jet charging signal to the ink jet; shifting the phase of the narrow jet charging signal with respect to a stimulation signal; and sensing the phase at which the ink jet first impacts the face of the ink catcher to determine the proper phase relationship.
Claim 18
Independent Claim
101 words
A method for determining the proper phase relationship between the stimulation and charging of a ink jet in a continuous type ink jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet; characterized by the steps of: generating and applying a narrow jet charging signal to the ink jet; shifting the phase of the narrow jet charging signal with respect to a stimulation signal; and sensing the phase at which the ink jet first impacts the face of the ink catcher to determine the proper phase relationship.
Claim 19
Dependent Claim
103 words
A continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, including means for adjusting ink drop charging voltage, characterized by: means for sensing the impact position of the ink jet on the vertical face of the catcher to produce an impact position signal; means for generating and applying a varying charge voltage to the ink jet; and means responsive to the impact position signal for detecting the charge voltage at which the impact position signal reaches a predetermined value corresponding to a good print quality.
Claim 20
Dependent Claim
103 words
A continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, including means for adjusting ink drop charging voltage, characterized by: means for sensing the impact position of the ink jet on the vertical face of the catcher to produce an impact position signal; means for generating and applying a varying charge voltage to the ink jet; and means responsive to the impact position signal for detecting the charge voltage at which the impact position signal reaches a predetermined value corresponding to a good print quality.
Claim 21
Dependent Claim
62 words
The ink jet printing apparatus claimed in claim 15, characterized in that said means for sensing the impact position of the ink jet on the vertical face of the ink catcher includes means for exhibiting a variable electrical property as a function of the portion of the surface that is wetted by the ink, and means for sensing the variable electrical property.
Claim 22
Independent Claim
76 words
A method for determining ink drop charging voltages in a continuous ink jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by the steps of: generating and applying a varying charge voltage to the ink jet; and sensing the charge voltage at which the ink jet is deflected to a predetermined position on the vertical face of the ink catcher.
Claim 23
Independent Claim
76 words
A method for determining ink drop charging voltages in a continuous ink jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by the steps of: generating and applying a varying charge voltage to the ink jet; and sensing the charge voltage at which the ink jet is deflected to a predetermined position on the vertical face of the ink catcher.
Claim 24
Dependent Claim
129 words
A multi-jet continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet including means for sensing ink jet array straightness characterized by: means for sensing the impact position on an ink jet on the vertical face of the ink catcher to produce an impact position signal; means for generating and applying a varying voltage to the ink jets, one at a time; means responsive to the impact position signal for detecting the charge voltage at which the impact position signal reaches a predetermined value for each ink jet; and means responsive to the variation in detected charge voltages for the multiple ink jets for producing a signal representing ink jet array straightness.
Claim 25
Dependent Claim
129 words
A multi-jet continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet including means for sensing ink jet array straightness characterized by: means for sensing the impact position on an ink jet on the vertical face of the ink catcher to produce an impact position signal; means for generating and applying a varying voltage to the ink jets, one at a time; means responsive to the impact position signal for detecting the charge voltage at which the impact position signal reaches a predetermined value for each ink jet; and means responsive to the variation in detected charge voltages for the multiple ink jets for producing a signal representing ink jet array straightness.
Claim 26
Dependent Claim
68 words
The multi-jet continuous ink jet printing apparatus claimed in claim 18, characterized in that said means for sensing the impact position of the ink jet on the vertical face of the ink catcher includes means for exhibiting a variable electrical property as a function of the portion of the surface of the vertical face that is wetted by the ink, and means for sensing the variable electrical property.
Claim 27
Independent Claim
96 words
A method for determining ink jet array straightness in a multi-jet continuous jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by the steps of: generating and applying a varying charge voltage to the ink jets, one at a time; detecting the charge voltage for each jet that causes the jet to impact the vertical face of the ink catcher at a predetermined position; and sensing the variation in detected charge voltage as a measure of ink jet array straightness.
Claim 28
Independent Claim
96 words
A method for determining ink jet array straightness in a multi-jet continuous jet printer of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by the steps of: generating and applying a varying charge voltage to the ink jets, one at a time; detecting the charge voltage for each jet that causes the jet to impact the vertical face of the ink catcher at a predetermined position; and sensing the variation in detected charge voltage as a measure of ink jet array straightness.
Claim 29
Dependent Claim
93 words
Continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet including means for sensing a crooked ink jet while printing, characterized by: means for sensing the average position of the impact of ink jets on the vertical face of the ink catcher during a period when all of the ink jets are being deflected into the catcher; and means for detecting a change of the average impact position over time to indicate a crooked ink jet.
Claim 30
Dependent Claim
93 words
Continuous ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet including means for sensing a crooked ink jet while printing, characterized by: means for sensing the average position of the impact of ink jets on the vertical face of the ink catcher during a period when all of the ink jets are being deflected into the catcher; and means for detecting a change of the average impact position over time to indicate a crooked ink jet.
Claim 31
Dependent Claim
72 words
The ink jet printing apparatus claimed in claim 21, characterized in that the means for sensing the average position of impact of ink jets on the vertical face of the ink catcher includes means for exhibiting a variable electrical property as a function of the portion of the surface that is wetted by the ink, and means for sensing the variable electrical property to produce a signal representing the average impact position.
Claim 32
Independent Claim
85 words
A method of sensing a crooked ink jet while printing, in a multi-jet ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by: sensing the average position of impact of ink jets on the vertical face of the ink catcher during a period when all of the ink jets are deflected onto the catcher, and detecting a change in the average position over a period of time.
Claim 33
Independent Claim
85 words
A method of sensing a crooked ink jet while printing, in a multi-jet ink jet printing apparatus of the type having a print head with an ink catcher having a vertical face extending generally parallel to the ink jet, characterized by: sensing the average position of impact of ink jets on the vertical face of the ink catcher during a period when all of the ink jets are deflected onto the catcher, and detecting a change in the average position over a period of time.
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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) | 1989-12-22 | 1990-06-23 | 1990-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-22 | 1994-06-23 | 1994-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-22 | 1998-06-23 | 1998-12-23 | $7700.00 | Window Closed / Lapsed |