Patent US3893408A successfully refreshed from Google Patents.
US3893408A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Toner dispensing system
Assignee: Xerox Corp
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Filing: 1973-12-26
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Granted: 1975-07-08
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Expires: 1993-12-26
Abstract
Abstract An automatic developability control for a two-component development mixture having toner and conductive carrier. Additional toner may be supplied to the developer mixture when the ratio of toner to carrier has been depleted beyond a predetermined optimum. The developer with its conductive carrier is movable through a space where an electrical potential exists. Shorting is encountered when the toner concentration is so low that toned carrier beads will permit flows of current across the space, creating electrical shorts. Utilizing this effect, a toner dispenser may be triggered in accordance with the number of shorts per unit time.
Inventors
- 👤 Jerome E Lamel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:07
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0851
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
131 words
In a magnetic brush development system wherein a twocomponent developer, including conductive carrier particles and thermoplastic resinous toner particles adhering thereto triboelectrically, is brought into contact with a photoreceptive surface to be developed under the effect of a magnetic field generated by a magnetic brush roller, the improvement comprising, conducting means spaced from said magnetic brush roller by a predetermined gap through which the magnetically conveyed developer is passed, means to bias the magnetic brush roller, circuit means coupling said biased Magnetic brush roller with said conducting means, means responsive to shorts caused by undertoned carrier passing through said gap to determine the level of toner in the developer mixture, and means to dispense additional toner into the developer mixture in response to a predetermined number of shorts per unit time.
Claim 2
Dependent Claim
131 words
In a magnetic brush development system wherein a twocomponent developer, including conductive carrier particles and thermoplastic resinous toner particles adhering thereto triboelectrically, is brought into contact with a photoreceptive surface to be developed under the effect of a magnetic field generated by a magnetic brush roller, the improvement comprising, conducting means spaced from said magnetic brush roller by a predetermined gap through which the magnetically conveyed developer is passed, means to bias the magnetic brush roller, circuit means coupling said biased Magnetic brush roller with said conducting means, means responsive to shorts caused by undertoned carrier passing through said gap to determine the level of toner in the developer mixture, and means to dispense additional toner into the developer mixture in response to a predetermined number of shorts per unit time.
Claim 3
Dependent Claim
15 words
The structure as recited in claim 1 wherein said conducting means is a trimmer bar.
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) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |