Patent US3619720A successfully refreshed from Google Patents.
US3619720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrically assisted printing system
Assignee: Hurletron Inc
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Filing: 1969-08-28
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Granted: 1971-11-09
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Expires: 1989-08-28
Abstract
Abstract A printing system having an electric circuit supplying an output potential to assist transfer of ink to a dielectric substrate, the potential being gradually increased up to a breakdown potential of the substrate, for example of a rate of 10 percent per hour. Each time breakdown potential is reached, the applied potential is set back 10 percent and the increase started again, so that the applied potential will follow variations in the breakdown potential of the substrate. A severe fault in the substrate results in removal of the output potential during a timed interval followed by a rapid potential buildup toward breakdown potential, after which the normal cycle is resumed.
Inventors
- 👤 Daniel A Coberley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:22
CPC Classifications
B; B41; B41M; B41M1/00; B41M1/42; B41F; B41F9/00; B41F9/001
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
294 words
In a printing system, an electric circuit having an output for supplying an electric potential across an ink-receiving substrate for assisting in the transfer of ink to the substrate, said circuit comprising, electrical energy supplying means for supplying said output electric potential, automatic control means controlling said electrical energy supply means and operable during normal operation for gradually increasing said output electric potential at a relatively gradual rate of increase, automatic sensing means for automatically sensing when the output electric potential reaches a limiting potential value substantially equal to the breakdown potential of the substrate and for signaling such limiting potential condition, and automatic setback means coupled to said sensing means and responsive to said limiting potential condition during normal operation for automatically reducing the output electric potential to a reduced magnitude which is less than said limiting potential value but which is of a magnitude to maintain transfer of ink to the substrate, said automatic control means being automatically operable to gradually increase the output electric potential from said reduced magnitude at the completion of each cycle of the automatic setback means during normal operation, and safety circuit means responsive to a severe fault at the substrate to substantially remove the electric output potential during a safety cycle and to resume operation with a minimum value of electric potential which is substantially less than said reduced magnitude, said automatic control means being operable after a safety cycle to increase the output electric potential at a relatively rapid rate substantially greater than the relatively gradual rate of increase during normal operation, and said automatic control means being operable in response to the output potential reaching the limiting potential value to resume normal operation in the absence of a further severe fault in the substrate.
Claim 2
Dependent Claim
294 words
In a printing system, an electric circuit having an output for supplying an electric potential across an ink-receiving substrate for assisting in the transfer of ink to the substrate, said circuit comprising, electrical energy supplying means for supplying said output electric potential, automatic control means controlling said electrical energy supply means and operable during normal operation for gradually increasing said output electric potential at a relatively gradual rate of increase, automatic sensing means for automatically sensing when the output electric potential reaches a limiting potential value substantially equal to the breakdown potential of the substrate and for signaling such limiting potential condition, and automatic setback means coupled to said sensing means and responsive to said limiting potential condition during normal operation for automatically reducing the output electric potential to a reduced magnitude which is less than said limiting potential value but which is of a magnitude to maintain transfer of ink to the substrate, said automatic control means being automatically operable to gradually increase the output electric potential from said reduced magnitude at the completion of each cycle of the automatic setback means during normal operation, and safety circuit means responsive to a severe fault at the substrate to substantially remove the electric output potential during a safety cycle and to resume operation with a minimum value of electric potential which is substantially less than said reduced magnitude, said automatic control means being operable after a safety cycle to increase the output electric potential at a relatively rapid rate substantially greater than the relatively gradual rate of increase during normal operation, and said automatic control means being operable in response to the output potential reaching the limiting potential value to resume normal operation in the absence of a further severe fault in the substrate.
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) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |