Patent US3887845A successfully refreshed from Google Patents.
US3887845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copier photoreceptor charge control
Assignee: Xerox Corp
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Filing: 1973-09-26
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Granted: 1975-06-03
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Expires: 1993-09-26
Abstract
Abstract A charge control arrangement for a reproduction machine. The machine has a photoconductive member, the surface of which has been uniformly charged to permit the creation of a latent electrostatic image of the original being copied thereon. The latent image is then developed and thereafter transferred to a copy sheet. Following transfer, the photoconductive member is cleaned in preparation for another cycle. To monitor the charge on the photoconductive member, voltage across the copy machine transfer roll is sensed. From this, the corotron power supply is adjusted to provide a desired photoconductor charge level. Alternately, a control may be provided to automatically regulate the corotron power supply in response to the transfer roll voltage sensed. In this latter instance, sensor means to accomodate the presence of a copy sheet in the transfer roll nip is provided to obviate any erroneous readings due to the interposition of the copy sheet between the transfer roll and the photoconductive member. As a further embodiment, a separate conductive roller probe may be used instead of the transfer roller or in machines not having a transfer roller, the roller probe being disposed in physical contact with the photoconductive member.
Inventors
- 👤 Robert J Michatek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:49
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0266
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
87 words
The method of controlling the charge level on the photoreceptor of an electrostatic reproduction machine of the type having corona charging means for placing a charge on the photoreceptor in preparation for imaging together with means including a biased transfer roller to transfer images developed on said photoreceptor to copying material, the steps consisting of: interrupting bias to the transfer roller while measuring the transfer roller electrical output; and Adjusting said corona charging means to provide a predetermined transfer roller output repreesenting optimum charge on said photoreceptor.
Claim 2
Independent Claim
87 words
The method of controlling the charge level on the photoreceptor of an electrostatic reproduction machine of the type having corona charging means for placing a charge on the photoreceptor in preparation for imaging together with means including a biased transfer roller to transfer images developed on said photoreceptor to copying material, the steps consisting of: interrupting bias to the transfer roller while measuring the transfer roller electrical output; and Adjusting said corona charging means to provide a predetermined transfer roller output repreesenting optimum charge on said photoreceptor.
Claim 3
Independent Claim
87 words
The method of controlling the charge level on the photoreceptor of an electrostatic reproduction machine of the type having corona charging means for placing a charge on the photoreceptor in preparation for imaging together with means including a biased transfer roller to transfer images developed on said photoreceptor to copying material, the steps consisting of: interrupting bias to the transfer roller while measuring the transfer roller electrical output; and Adjusting said corona charging means to provide a predetermined transfer roller output repreesenting optimum charge on said photoreceptor.
Claim 4
Independent Claim
87 words
The method of controlling the charge level on the photoreceptor of an electrostatic reproduction machine of the type having corona charging means for placing a charge on the photoreceptor in preparation for imaging together with means including a biased transfer roller to transfer images developed on said photoreceptor to copying material, the steps consisting of: interrupting bias to the transfer roller while measuring the transfer roller electrical output; and Adjusting said corona charging means to provide a predetermined transfer roller output repreesenting optimum charge on said photoreceptor.
Claim 5
Dependent Claim
16 words
The means according to claim 1 including the step of measuring voltage across said transfer roller.
Claim 6
Dependent Claim
16 words
The method according to claim 1 including the step of measuring current across said transfer roller.
Claim 7
Dependent Claim
23 words
The method according to claim 1 including the step of terminating the feeding of copying material while measuring said transfer roller electrical output.
Claim 8
Dependent Claim
111 words
In an electrostatic reproduction machine of the type having corona charging means for generating a charge on the photoreceptor in preparation for imaging thereof together with means to transfer the images developed on said photoreceptor surface to copying material, said transfer means including a biased transfer roll, the combination of: means for monitoring voltage across said transfer roll during operation of said machine, means to interrupt bias to said transfer roller while said transfer roller voltage is being monitored, and means to adjust said corona charging means in response to said monitoring means output to provide a predetermined voltage across said transfer roller representing an optimum charge on said photoreceptor surface.
Claim 9
Dependent Claim
111 words
In an electrostatic reproduction machine of the type having corona charging means for generating a charge on the photoreceptor in preparation for imaging thereof together with means to transfer the images developed on said photoreceptor surface to copying material, said transfer means including a biased transfer roll, the combination of: means for monitoring voltage across said transfer roll during operation of said machine, means to interrupt bias to said transfer roller while said transfer roller voltage is being monitored, and means to adjust said corona charging means in response to said monitoring means output to provide a predetermined voltage across said transfer roller representing an optimum charge on said photoreceptor surface.
Claim 10
Dependent Claim
83 words
In an electrostatic reproduction machine of the type having corona charging means for generating a charge on the photoconductor in preparation for imaging thereof, the combination of: means to measure charges on said photoconductor, said charge measuring means including a probe member in physical and electrical contact with said photoconductor, an adjustable power source for said corona charging means, control means responsive to said charge measuring means for adjusting said charging means power source whereby to provide a predetermined charge on said photoconductor.
Claim 11
Dependent Claim
83 words
In an electrostatic reproduction machine of the type having corona charging means for generating a charge on the photoconductor in preparation for imaging thereof, the combination of: means to measure charges on said photoconductor, said charge measuring means including a probe member in physical and electrical contact with said photoconductor, an adjustable power source for said corona charging means, control means responsive to said charge measuring means for adjusting said charging means power source whereby to provide a predetermined charge on said photoconductor.
Claim 12
Dependent Claim
37 words
The reproduction machine according to claim 7 in which said reproduction machine includes a transfer roller cooperable with said photoconductor to transfer images developed on said photoconductor to copying material, said probe member comprising said transfer roller.
Claim 13
Dependent Claim
30 words
The reproduction machine according to claim 7 in which said probe member comprises a roller, and means supporting said roller in rotatable engagement with the surface of said photoconductor member.
Claim 14
Dependent Claim
35 words
The reproduction machine according to claim 9 in which said roller supporting means supports said roller in engagement with said photoconductive member after said photoconductive member is charged but before said photoconductive member is imaged.
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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |