Patent US4323905A successfully refreshed from Google Patents.
US4323905A
Expired / Lapsed
US
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Ink droplet sensing means
Assignee: NCR Voyix Corp
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Filing: 1980-11-21
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Granted: 1982-04-06
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Expires: 2000-11-21
Abstract
Abstract An ink droplet sensing means for detecting whether or not droplets are impinging on record media during ink jet printing operations. A synthetic foil having a metal layer is placed over a counter electrode having a rough surface on one side and a voltage is then applied to the electrode and the metal layer. Ink droplets impinging on the foil momentarily deflect the foil and cause a change in capacity which in turn causes a voltage change at the electrode. The voltage change is coupled through a capacitor and an amplifier and through recognition logic for evaluation of the signals.
Inventors
- 👤 Peter H. Reitberger
- 👤 Helmut Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:17
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/07; B41J2/125
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
87 words
Apparatus for detecting the presence of ink droplets comprising an electrode member having an uneven surface, an insulating sheet covering the uneven surface, said sheet having a conductive coating on one side thereof distal from the electrode member, and voltage means connected to said electrode and to the conductive coating and responsive to ink droplets impinging on and deflecting said insulating sheet thereby causing a change in voltage at the electrode to indicate the impact of the ink droplets and to generate a pulse in response thereto.
Claim 2
Dependent Claim
87 words
Apparatus for detecting the presence of ink droplets comprising an electrode member having an uneven surface, an insulating sheet covering the uneven surface, said sheet having a conductive coating on one side thereof distal from the electrode member, and voltage means connected to said electrode and to the conductive coating and responsive to ink droplets impinging on and deflecting said insulating sheet thereby causing a change in voltage at the electrode to indicate the impact of the ink droplets and to generate a pulse in response thereto.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 wherein said electrode member is a metallic block having said uneven surface on one side thereof to receive impact of said ink droplets.
Claim 4
Dependent Claim
18 words
The apparatus of claim 1 wherein said electrode member includes a plurality of grooves on one face thereof.
Claim 5
Dependent Claim
22 words
The apparatus of claim 1 wherein said insulating sheet comprises a thin foil stretched across the uneven surface of the electrode member.
Claim 6
Dependent Claim
16 words
The apparatus of claim 1 wherein the insulating sheet includes a conductive layer of metal thereon.
Claim 7
Dependent Claim
31 words
The apparatus of claim 1 wherein said voltage means includes a resistor and a capacitor connected for causing a change in capacitance upon impact of ink droplets on said insulating sheet.
Claim 8
Dependent Claim
32 words
The apparatus of claim 1 including means adjacent the uneven surface of the electrode member for maintaining an atmosphere of moist air for preventing drying of ink droplets on the conductive coating.
Claim 9
Dependent Claim
135 words
In an ink jet printer having a print head and record media for receiving droplets of ink from said print head, means for detecting the presence of ink droplets comprising an electrode element positioned in relation to the print head to be impacted by ink droplets therefrom, a surface of said electrode element including a series of indentations to provide an uneven surface, a foil sheet covering the surface of said electrode element and having a conductive coating on one side thereof, and means connected with said electrode element for applying a voltage between the element and ground potential and responsive to impacting of ink droplets toward and against the foil sheet covering the indentations to cause a voltage change at the electrode element and generate a pulse in response to the change in voltage.
Claim 10
Dependent Claim
135 words
In an ink jet printer having a print head and record media for receiving droplets of ink from said print head, means for detecting the presence of ink droplets comprising an electrode element positioned in relation to the print head to be impacted by ink droplets therefrom, a surface of said electrode element including a series of indentations to provide an uneven surface, a foil sheet covering the surface of said electrode element and having a conductive coating on one side thereof, and means connected with said electrode element for applying a voltage between the element and ground potential and responsive to impacting of ink droplets toward and against the foil sheet covering the indentations to cause a voltage change at the electrode element and generate a pulse in response to the change in voltage.
Claim 11
Dependent Claim
25 words
In the printer of claim 8 wherein said electrode element is a metallic block formed to receive impact of ink droplets on one surface thereof.
Claim 12
Dependent Claim
27 words
In the printer of claim 8 wherein the series of indentations are spaced to receive ink droplets from the respective column of nozzles of the print head.
Claim 13
Dependent Claim
21 words
In the printer of claim 8 wherein the foil sheet is an insulating medium stretched across the indentations of said surface.
Claim 14
Dependent Claim
22 words
In the printer of claim 8 wherein the foil sheet includes a conductive coating of metal thereon distal from the electrode element.
Claim 15
Dependent Claim
33 words
In the printer of claim 8 wherein said voltage applying means includes a resistor and a capacitor connected for causing a change in capacitance upon impact of ink droplets on said foil sheet.
Claim 16
Dependent Claim
30 words
In the printer of claim 8 including means adjacent the surface of said electrode element for maintaining a moist atmosphere for preventing drying of ink droplets on the conductive coating.
Claim 17
Dependent Claim
18 words
In the printer of claim 8 including circuit means for filtering noise from the ink droplet detecting means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-05 | 1985-10-05 | 1986-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-05 | 1989-10-05 | 1990-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-05 | 1993-10-05 | 1994-04-06 | $7700.00 | Window Closed / Lapsed |