US3737222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Copying machine
Assignee: BRIGGS BY VIERS
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Filing: 1971-11-19
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Granted: 1973-06-05
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Expires: 1991-11-19
Abstract
Abstract An improved electrostatic copying machine which utilizes a novel, biased double screen arrangement to form latent electrostatic image on a dielectric receiving layer, such as paper or the like, is disclosed. The double screen arrangement includes a first wire mesh screen having a photoconductive coating thereon and a second wire mesh screen having either a photoconductive coating or an insulator coating thereon. These screens are positioned, one above the other, between a conventional corona device and the receiving layer, with the first screen being positioned adjacent to the corona device and the second screen being positioned adjacent to the receiving layer. The first screen is biased with respect to the receiving layer and with respect to the second screen and the second screen is biased with respect to the receiving layer. A latent electrostatic image is formed on the receiving layer by projecting an optical image of the original to be copied onto the first screen while simultaneously raising the corona device to a corona discharge potential. The latent electrostatic image thus formed on the receiving layer is then made visible by suitable developing techniques known to the art.
Inventors
- 👤 L Briggs
- 👤 D Kazen
- 👤 V Viers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:19
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/05; G03G15/051
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
371 words
An improved copying machine for reproducing, on a dielectric receiving layer, an optical image conforming to an original to be copied, the improved machine comprising: a. means adapted for forming latent electrostatic image on a surface of a dielectric receiving layer comprising: means adapted to support the receiving layer while an electrostatic image is being formed thereon; ion generating source positioned at one side of and spaced from said surface of the receiving layer as it is supported by the supporting means; relatively high voltage power supply means which, when connected to the ion generating source, maintains the ion generating source at an ion discharge potential; first electrically conductive, electrostatic and electrophotographic grid means spaced from and positioned between the ion generating source and the receiving layer as it is supported by the supporting means; biasing control grid means spaced from and positioned between the first grid means and the receiving layer as it is supported by the supporting means, the biasing control grid means having an electrically insulating outer coating thereon; first means for electrically biasing the first grid means with respect to the biasing control grid means and with respect to the receiving layer as it is supported by the supporting means; second means for electrically biasing the biasing control grid means with respect to the receiving layer as it is supported by the supporting means; means for projecting an optical image, conforming to the original to be copied, onto one surface of the first grid means; and means for connecting the power supply meAns to the ion generating source, and thus causing ion discharge, simultaneously while said optical image is being projected onto the first grid means, while the first biasing means biases the first grid means with respect to the biasing control grid means and with respect to the receiving layer, and while the second biasing means biases the biasing control grid means with respect to the receiving layer; b. means for applying toner to the electrostatic image formed on the receiving layer; c. means for fixing the toner on the receiving layer; and d. means for transporting the receiving layer from the supporting means to the toner applying means and then to the toner fixing means.
Claim 2
Dependent Claim
371 words
An improved copying machine for reproducing, on a dielectric receiving layer, an optical image conforming to an original to be copied, the improved machine comprising: a. means adapted for forming latent electrostatic image on a surface of a dielectric receiving layer comprising: means adapted to support the receiving layer while an electrostatic image is being formed thereon; ion generating source positioned at one side of and spaced from said surface of the receiving layer as it is supported by the supporting means; relatively high voltage power supply means which, when connected to the ion generating source, maintains the ion generating source at an ion discharge potential; first electrically conductive, electrostatic and electrophotographic grid means spaced from and positioned between the ion generating source and the receiving layer as it is supported by the supporting means; biasing control grid means spaced from and positioned between the first grid means and the receiving layer as it is supported by the supporting means, the biasing control grid means having an electrically insulating outer coating thereon; first means for electrically biasing the first grid means with respect to the biasing control grid means and with respect to the receiving layer as it is supported by the supporting means; second means for electrically biasing the biasing control grid means with respect to the receiving layer as it is supported by the supporting means; means for projecting an optical image, conforming to the original to be copied, onto one surface of the first grid means; and means for connecting the power supply meAns to the ion generating source, and thus causing ion discharge, simultaneously while said optical image is being projected onto the first grid means, while the first biasing means biases the first grid means with respect to the biasing control grid means and with respect to the receiving layer, and while the second biasing means biases the biasing control grid means with respect to the receiving layer; b. means for applying toner to the electrostatic image formed on the receiving layer; c. means for fixing the toner on the receiving layer; and d. means for transporting the receiving layer from the supporting means to the toner applying means and then to the toner fixing means.
Claim 3
Dependent Claim
33 words
The improved machine described in claim 1 wherein the first grid means is a wire mesh screen having a photoconductive coating thereon; and wherein the first biasing means is connected the wire mesh.
Claim 4
Dependent Claim
36 words
The improved machine described in claim 2 wherein the biasing control grid means is a wire mesh screen having an electrical insulating coating thereon; and wherein the second biasing means is connected to the wire mesh.
Claim 5
Dependent Claim
35 words
The improved machine described in claim 2 wherein the biasing control grid means is a wire mesh screen having a photoconductive coating thereon; and wherein the second biasing means is connected to the wire mesh.
Claim 6
Dependent Claim
43 words
The improved machine described in claim 2 which includes means for varying strength of the electric field between the biasing control grid means and the first grid means so as to vary the contrast of the electrostatic image formed on the receiving layer.
Claim 7
Dependent Claim
312 words
For use in a copying machine, an improved apparatus for reproducing, on a surface of a dielectric receiving layer, an electrostatic image conforming to an optical image to be copied, the improved apparatus comprising: means adapted to support the receiving layer while an electrostatic image is being formed thereon; an ion generating source positioned at one side of and spaced from the surface of the receiving layer as it is supported on the supporting means; relatively high voltage power supply means which, when connected to the ion generating source, maintains the ion generating source at an ion discharge potential; first conductive, electrostatic and electrophotographic grid means spaced from and positioned between the corona generating means and the receiving layer as it is supported by the supporting means; biasing control grid means spaced from and positioned between the first grid means and the receiving layer as it is supported by the supporting means, the biasing control grid means having an electrically insulating outer coating thereon; first means for electrically biasing the first grid means with respect to the biasing control grid means and with respect to the receiving layer as it is supported by the supporting means; second means for electrically biasing the biasing control grid means with respect to the receiving layer as it is supported by the supporting means; means for projecting an optical image, conforming to the original to be copied, onto the first grid means; and means for connecting the power supply means to the ion generating source, and thus causing ion discharge, simultaneously while the optical image is being projected onto the first grid means, while the first biasing means biases the first grid means with respect to the biasing control grid means and with respect to the receiving layer, and while the second biasing means biases the biasing control grid means with respect to the receiving layer.
Claim 8
Dependent Claim
312 words
For use in a copying machine, an improved apparatus for reproducing, on a surface of a dielectric receiving layer, an electrostatic image conforming to an optical image to be copied, the improved apparatus comprising: means adapted to support the receiving layer while an electrostatic image is being formed thereon; an ion generating source positioned at one side of and spaced from the surface of the receiving layer as it is supported on the supporting means; relatively high voltage power supply means which, when connected to the ion generating source, maintains the ion generating source at an ion discharge potential; first conductive, electrostatic and electrophotographic grid means spaced from and positioned between the corona generating means and the receiving layer as it is supported by the supporting means; biasing control grid means spaced from and positioned between the first grid means and the receiving layer as it is supported by the supporting means, the biasing control grid means having an electrically insulating outer coating thereon; first means for electrically biasing the first grid means with respect to the biasing control grid means and with respect to the receiving layer as it is supported by the supporting means; second means for electrically biasing the biasing control grid means with respect to the receiving layer as it is supported by the supporting means; means for projecting an optical image, conforming to the original to be copied, onto the first grid means; and means for connecting the power supply means to the ion generating source, and thus causing ion discharge, simultaneously while the optical image is being projected onto the first grid means, while the first biasing means biases the first grid means with respect to the biasing control grid means and with respect to the receiving layer, and while the second biasing means biases the biasing control grid means with respect to the receiving layer.
Claim 9
Dependent Claim
34 words
The improved apparatus described in claim 6 wherein the first grid means is a wire mesh screen having a photoconductive coating thereon; and wherein the first biasing means is connected to the wire mesh.
Claim 10
Dependent Claim
35 words
The improved apparatus described in claim 7 wherein the biasing control grid means is a wire mesh screen having an insulating coating thereon; and wherein the second biasing means is connected to the wire mesh.
Claim 11
Dependent Claim
35 words
The improved apparaTus described in claim 7 wherein the biasing control grid means is a wire mesh screen having a photoconductive coating thereon; and wherein the second biasing means is connected to the wire mesh.
Claim 12
Dependent Claim
146 words
The improved apparatus described in claim 8 wherein an electric field of between approximately 1,000 volts per centimeter to 20,000 volts per centimeter exists between the biasing control grid means and the receiving layer as it is supported by the support means, with the separation distance between the biasing control grid means and the receiving layer being between approximately 1 millimeter and 3 centimeters; wherein an electric field of between approximately 500 volts per centimeter to 10,000 volts per centimeter exists between the first grid means and the biasing control grid means, with a separation distance between the first grid means and the biasing control grid means being between approximately 1 millimeter and 1 centimeter; and wherein an electric field, resulting from the corona discharge, of between approximately 3,000 volts per centimeter to 10,000 volts per centimeter exists in the region of the first grid means.
Claim 13
Dependent Claim
42 words
The improved apparatus in claim 10 which includes means for varying strength of the electric field between biasing control grid means and the first grid means so as to vary the contrast of the developed electrostatic image formed on the receiving layer.
Claim 14
Dependent Claim
43 words
The improved apparatus described in claim 10 wherein the separation distance between the first grid means and the biasing control grid means is less than 1 centimeter and wherein the coating on wire mesh screen of the biasing control grid means is photoconductive.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |