US3880119A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Development apparatus
Assignee: Xerox Corp
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Filing: 1973-12-20
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Granted: 1975-04-29
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Expires: 1993-12-20
Abstract
Abstract An improved copier system in which a photoconductive member bearing a latent electrostatic image is developed by cascade development followed by magnetic development in one mode of operation when solid area image development is desired and by cascade development alone when line or edge development is desired. A magnetic development roll unit is positioned at the lower part of the development housing of the development system in close proximity to the photoconductive member being developed. The photoconductive member is selectively developed by the magnetic development roll unit upon operational development thereof. A control button on the copier control panel sets the development mode of operation as desired.
Inventors
- 👤 Lawrence J Fraser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:56
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
130 words
In a xerographic copier system in which a xerographic member bearing latent electrostatic images is advanced through processing station for producing high quality copies, improved development apparatus for developing line or solid area copies comprising first development means for cascading a two-component magnetic developer material across a moving xerographic member bearing latent electrostatic images to be developed, second development means including magnetic development means positioned in the path of said latent electrostatic image subsequent to the first development means, said magnetic development means having an operative condition for development of solid area portions of the latent electrostatic images and an inoperative condition when no development occurs thereof, means for actuating magnetic development means to cause development of the solid area portions of the images at the option of the operator.
Claim 2
Dependent Claim
130 words
In a xerographic copier system in which a xerographic member bearing latent electrostatic images is advanced through processing station for producing high quality copies, improved development apparatus for developing line or solid area copies comprising first development means for cascading a two-component magnetic developer material across a moving xerographic member bearing latent electrostatic images to be developed, second development means including magnetic development means positioned in the path of said latent electrostatic image subsequent to the first development means, said magnetic development means having an operative condition for development of solid area portions of the latent electrostatic images and an inoperative condition when no development occurs thereof, means for actuating magnetic development means to cause development of the solid area portions of the images at the option of the operator.
Claim 3
Dependent Claim
37 words
Apparatus according to claim 1 in which said magnetic development means is driven by a reversible drive which causes development of the images when moving in a first direction and non-development when moving in a second direction.
Claim 4
Dependent Claim
25 words
Apparatus according to claim 2 wherein said magnetic development means comprises a cylindrical member rotatable on an axis in close proximity to said xerographic member.
Claim 5
Dependent Claim
37 words
Apparatus according to claim 3 wherein said xerographic member is in the form of a drum and said cylindrical member is positioned to receive at least a portion of the cascading developer material across the drum surface.
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) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |