US4124287A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Imaging system utilizing uncharged marking particles
Assignee: Xerox Corp
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Filing: 1977-03-31
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Granted: 1978-11-07
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Expires: 1997-03-31
Abstract
Abstract An apparatus for imagewise marking a photoconductive imaging surface includes a means for forming an imagewise non-uniform charge pattern on the surface and a means for contacting the surface with uncharged marking particles.
Inventors
- 👤 Lloyd F. Bean
- 👤 Roger L. Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:52
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/04; G03G15/04027; G03G13/00; G03G13/22; Y; Y10; Y10S; Y10S118/00; Y10S118/05
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
75 words
An apparatus for producing a visible image on a photoconductive imaging surface which comprises: (a) a means for forming an imagewise non-uniform charge pattern having an average strength of at least about 100 volts on a photoconductive surface having a thickness of at least about 1.25 microns; and (b) a means for contacting the surface with finely divided uncharged marking particles having a dielectric constant of at least about 1.5 more than the surrounding medium.
Claim 2
Independent Claim
75 words
An apparatus for producing a visible image on a photoconductive imaging surface which comprises: (a) a means for forming an imagewise non-uniform charge pattern having an average strength of at least about 100 volts on a photoconductive surface having a thickness of at least about 1.25 microns; and (b) a means for contacting the surface with finely divided uncharged marking particles having a dielectric constant of at least about 1.5 more than the surrounding medium.
Claim 3
Dependent Claim
47 words
The apparatus of claim 1 wherein the means for forming includes a charging means for uniformly charging the surface, an exposure means for discharging the surface in a regular pattern of light and dark and an exposure means for subsequently discharging the surface in an imagewise pattern.
Claim 4
Dependent Claim
36 words
The apparatus of claim 1 wherein the means for forming includes a means for placing a regular pattern of non-uniform charge on the surface and a means for discharging the regular pattern in an imagewise pattern.
Claim 5
Dependent Claim
42 words
The apparatus of claim 1 wherein the means for forming includes a means for uniformly charging the surface of a layer comprising a conductive substrate supporting a regular pattern of photoconductive deposits and a means for subsequently imagewise exposing the charged layer.
Claim 6
Dependent Claim
23 words
The apparatus of claim 4 wherein at least the portions of the surface not covered by deposits is coated with a leaky insulator.
Claim 7
Dependent Claim
30 words
The apparatus of claim 1 wherein the means for contacting is a magnetic brush positioned to apply to the surface finely divided uncharged marking particles containing a magnetically attractable material.
Claim 8
Dependent Claim
25 words
The apparatus of claim 1 wherein the means for contacting is an electric brush positioned to apply to the surface finely divided uncharged marking particles.
Claim 9
Dependent Claim
23 words
The apparatus of claim 1 wherein the means for contacting is an arrangement for flowing finely divided uncharged marking particles over the surface.
Claim 10
Dependent Claim
25 words
The apparatus of claim 1 wherein the means for contacting is a fluidized bed of finely divided uncharged marking particles positioned for contacting the surface.
Claim 11
Dependent Claim
16 words
The apparatus of claim 1 further including means for transferring the image to a receiving member.
Claim 12
Dependent Claim
17 words
The apparatus of claim 10 further including means for fixing the transferred image to the receiving member.
Claim 13
Dependent Claim
15 words
The apparatus of claim 1 further including means for fixing the image to the surface.
Claim 14
Dependent Claim
17 words
The apparatus of claim 1 further including means for cleaning and discharging the surface prior to reuse.
Claim 15
Dependent Claim
22 words
The apparatus of claim 1 wherein the imagewise non-uniform charge pattern has a period of from about 25 microns to 175 microns.
Claim 16
Dependent Claim
20 words
The apparatus of claim 1 wherein the marking particles have a diameter of from about 5 to about 30 microns.
Claim 17
Dependent Claim
42 words
The apparatus of claim 1 wherein the means for forming includes a charging means for uniformly charging the surface and means for simultaneously exposing the surface to a regular pattern of dark and light and an imagewise pattern of dark and light.
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) | 1981-11-06 | 1982-05-08 | 1982-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-06 | 1986-05-08 | 1986-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-06 | 1990-05-08 | 1990-11-07 | $7700.00 | Window Closed / Lapsed |