US4550327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for discharging liquid droplets
Assignee: Canon Inc
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Filing: 1984-10-10
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Granted: 1985-10-29
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Expires: 2004-10-10
Abstract
Abstract A device for discharging droplets liquid within nozzles as liquid droplets by utilizing thermal energy comprises said nozzles each provided therein or thereby with a conductive element to detect the state of liquid in the nozzle by measuring the change of electric current passing the conductive element.
Inventors
- 👤 Akira Miyakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:04
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/015; B41J2/04; B41J2/045; B41J2/04501; B41J2/0451; B41J2/04555; B41J2/04563; B41J2/04565; B41J2/0458; B41J2/135; B41J2/14; B41J2002/14354
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
89 words
A device for discharging liquid as liquid droplets, comprising: at least one nozzle for providing a liquid flow path; heating means for applying thermal energy to an area of said nozzle; and means for detecting the absence of liquid in said area, including a conductive element having an electrical conductivity that varies according to the temperature of said conductive element, said conductive element being disposed proximate to said area for detecting changes in the temperature thereof in accordance with changes in the electric current passing through said conductive element.
Claim 2
Independent Claim
89 words
A device for discharging liquid as liquid droplets, comprising: at least one nozzle for providing a liquid flow path; heating means for applying thermal energy to an area of said nozzle; and means for detecting the absence of liquid in said area, including a conductive element having an electrical conductivity that varies according to the temperature of said conductive element, said conductive element being disposed proximate to said area for detecting changes in the temperature thereof in accordance with changes in the electric current passing through said conductive element.
Claim 3
Dependent Claim
15 words
A device according to claim 1, wherein said heating means includes a resistance heating element.
Claim 4
Dependent Claim
13 words
A device according to claim 1, further comprising a plurality of said nozzles.
Claim 5
Dependent Claim
20 words
A device according to claim 1, wherein said conductive element detects the rate of change of temperature of said area.
Claim 6
Dependent Claim
28 words
A device according to claim 4, wherein said heating means is disabled when the rate of change of the temperature of said area is above a reference level.
Claim 7
Dependent Claim
30 words
A device according to claim 5, wherein the reference level corresponds to the rate of change of the temperature of said area when there is an absence of liquid therein.
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) | 1988-10-28 | 1989-04-29 | 1989-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-28 | 1993-04-29 | 1993-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-28 | 1997-04-29 | 1997-10-29 | $7700.00 | Window Closed / Lapsed |