US3846020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic sheet transport system
Assignee: Xerox Corp
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Filing: 1973-12-03
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Granted: 1974-11-05
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Expires: 1993-12-03
Abstract
Abstract A transport for paper or other copy sheets consisting of a photoconductive belt which is corona charged and then optically exposed to a fine pattern of closely spaced alternating adjacent light and dark areas to provide a correspondingly fine electrostatic pattern of alternating charged and discharged areas on the belt. This provides a fine pattern of fringe fields for electrostatically holding either charged or uncharged paper on the belt. The charge pattern spacing is preferably that of the paper thickness or less so that the system may be utilized for the transport of a copy sheet through a zerographic transfer station without affecting image transfer.
Inventors
- 👤 G Fletcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:40
CPC Classifications
B; B65; B65H; B65H5/00; B65H5/02; B65H5/021; G; G03; G03G; G03G15/00; G03G15/65; G03G15/6529; Y; Y10; Y10S; Y10S271/00; Y10S271/901
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
131 words
In an electrostatographic copying system in which an image is formed on an imaging surface and transferred at a transfer station to a copy sheet, the improvement comprising: copy sheet transport means including a copy sheet supporting surface, said supporting surface being photoconductively electrically dischargable; support means for said transport means for moving said supporting surface intimately past said imaging surface; charging means for electrically charging said supporting surface, and optical means for optically imaging a fine light pattern of closely alternating adjacent light and dark areas on said supporting surface, subsequent to said electrical charging thereof by said charging means, for photoconductively discharging said supporting surface into a fine charge pattern of alternating closely adjacent charged and discharged areas on said supporting surface providing copy sheet retaining electrical fringe fields.
Claim 2
Dependent Claim
131 words
In an electrostatographic copying system in which an image is formed on an imaging surface and transferred at a transfer station to a copy sheet, the improvement comprising: copy sheet transport means including a copy sheet supporting surface, said supporting surface being photoconductively electrically dischargable; support means for said transport means for moving said supporting surface intimately past said imaging surface; charging means for electrically charging said supporting surface, and optical means for optically imaging a fine light pattern of closely alternating adjacent light and dark areas on said supporting surface, subsequent to said electrical charging thereof by said charging means, for photoconductively discharging said supporting surface into a fine charge pattern of alternating closely adjacent charged and discharged areas on said supporting surface providing copy sheet retaining electrical fringe fields.
Claim 3
Dependent Claim
36 words
The copying system of claim 1 wherein said optical means includes an original image pattern of alternating closely adjacent light and dark areas, and lens means for imaging said original image pattern over said supporting surface.
Claim 4
Dependent Claim
47 words
The copying system of claim 1 wherein said copy sheet is moved on said support surface into and out of engagement with said imaging surface at said transfer station, retained on said support surface by said fine charge pattern of alternating closed adjacent charged and discharged areas.
Claim 5
Dependent Claim
29 words
The copying system of claim 3 wherein said spacing of said alternating charged and discharged areas is sufficiently fine that said image transfer at said transfer station is unaffected.
Claim 6
Dependent Claim
27 words
The copying system of claim 3 wherein said spacing of said alternating charged and discharged areas is not substantially greater than the thickness of said copy sheet.
Claim 7
Dependent Claim
22 words
The copying system of claim 3 wherein said spacing of said alternating charged and uncharged areas is less than approximately 0.13 millimeters.
References Cited (Backward Citations)
US3642362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |