US4514741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal ink jet printer utilizing a printhead resistor having a central cold spot
Assignee: HP Inc
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Filing: 1982-11-22
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Granted: 1985-04-30
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Expires: 2002-11-22
Abstract
Abstract A thermal ink jet printer utilizes a printhead resistor which has a central conductive region to excite bubble growth and to cause ejection of ink droplets. The existence of the central conductive region causes bubbles to be created which are toroidal in shape and which fragment during collapse, thereby randomly distributing the resultant acoustic shock across the surface of the printhead resistor and minimizing cavitation damage.
Inventors
- 👤 John D. Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:22
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/14; B41J2/14016; B41J2/14088; B41J2/14112; B41J2/1412; B41J2202/00; B41J2202/01; B41J2202/03; B41J2202/11
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
62 words
A thermal ink jet printer, responsive to a control signal, for ejecting an ink droplet from a capillary region, the thermal ink jet printer comprising a printhead resistor in thermal contact with the capillary region for receiving the control signal, the printhead resistor being composed of a resistive region and a conductive region located within said resistive region and electrically connected thereto.
Claim 2
Dependent Claim
62 words
A thermal ink jet printer, responsive to a control signal, for ejecting an ink droplet from a capillary region, the thermal ink jet printer comprising a printhead resistor in thermal contact with the capillary region for receiving the control signal, the printhead resistor being composed of a resistive region and a conductive region located within said resistive region and electrically connected thereto.
Claim 3
Dependent Claim
25 words
A thermal ink jet printer as in claim 1, wherein the resistivity of the conductive region is less than the resistivity of the resistive region.
Claim 4
Dependent Claim
24 words
A thermal ink jet printer as in claim 2, wherein the conductive region is located at substantially the geometric center of the resistive region.
Claim 5
Dependent Claim
16 words
A thermal ink jet printer as in claim 3, wherein the conductive region is substantially circular.
Claim 6
Dependent Claim
16 words
A thermal ink jet printer as in claim 4, wherein the conductive region comprises gold film.
Claim 7
Dependent Claim
114 words
A thermal ink jet printer, responsive to a control signal, for ejecting an ink droplet from a capillary region, the thermal ink jet printer comprising a printhead resistor in thermal contact with the capillary region for receiving the control signal, the printhead resistor comprising: first, second and third current paths electrically connected in parallel; a first insulator attached between the first and second current paths; a second insulator attached between the second and third current paths; the first and third current paths each comprising a central resistive region and upper and lower conductive regions connected thereto; and the second current path comprising a central conductive region and upper and lower resistive regions connected thereto.
Claim 8
Dependent Claim
114 words
A thermal ink jet printer, responsive to a control signal, for ejecting an ink droplet from a capillary region, the thermal ink jet printer comprising a printhead resistor in thermal contact with the capillary region for receiving the control signal, the printhead resistor comprising: first, second and third current paths electrically connected in parallel; a first insulator attached between the first and second current paths; a second insulator attached between the second and third current paths; the first and third current paths each comprising a central resistive region and upper and lower conductive regions connected thereto; and the second current path comprising a central conductive region and upper and lower resistive regions connected thereto.
Claim 9
Dependent Claim
21 words
A printhead resistor as in claim 6, wherein the resistances of the first, second, and third current paths are substantially equal.
Claim 10
Dependent Claim
34 words
A printhead resistor as in claim 7, wherein the central conductive region of the second current path is substantially equidistant from the upper and lower conductive regions of the first and third current paths.
Claim 11
Dependent Claim
23 words
A printhead resistor as in claim 8, wherein the resistivity of the conductive regions is less than the resistivity of the resistive regions.
Claim 12
Dependent Claim
14 words
A printhead resistor as in claim 9, wherein the conductive regions comprise gold film.
Claim 13
Dependent Claim
18 words
A thermal ink jet printer as in claim 1, wherein the capillary region is substantially filled with ink.
Claim 14
Dependent Claim
18 words
A thermal ink jet printer as in claim 4, wherein the capillary region is substantially filled with ink.
Claim 15
Dependent Claim
18 words
A thermal ink jet printer as in claim 6, wherein the capillary region is substantially filled with ink.
Claim 16
Dependent Claim
18 words
A thermal ink jet printer as in claim 7, wherein the capillary region is substantially filled with ink.
Claim 17
Dependent Claim
18 words
A thermal ink jet printer as in claim 8, wherein the capillary region is substantially filled with ink.
Claim 18
Dependent Claim
18 words
A thermal ink jet printer as in claim 9, wherein the capillary region is substantially filled with ink.
References Cited (Backward Citations)
US1381093A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-29 | 1988-10-29 | 1989-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-29 | 1992-10-29 | 1993-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-29 | 1996-10-29 | 1997-04-30 | $7700.00 | Window Closed / Lapsed |