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US3817615A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for preventing soiling of the trailing end portion of a transfer sheet

Assignee: Ricoh Co Ltd
•
Filing: 1972-12-18
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Granted: 1974-06-18
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Expires: 1992-12-18
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Abstract

Abstract A device for use with electrostatic latent image transferprinting apparatus to prevent soiling of the trailing end portion of the transfer-printing sheet due to overcharging, which device is disposed in a position to impress a bias voltage of the same charge as the electrostatic latent image on the electricallyconducting material layer underside of the transfer-printing sheet immediately after the latent-image containing dielectric upper layer is stripped from the surface of the image forming member.

Inventors

  • 👤 T Adachi
  • 👤 K Kasuya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 21:14
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/18

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 175 words
In an electrophotographic reproduction device of the transfer-printing type in which an electrostatic latent image is formed on the dielectric surface of an image forming member having a dielectric layer on an electrically conducting material layer, and the dielectric surface of a transfer-printing sheet having a dielectric layer provided on an electrically conducting material layer is brought into intimate contact with the electrostatic latent image bearing surface of the image forming member and then stripped off to effect transfer-printing of the electrostatic latent image on the transfer-printing sheet, the improvement comprising voltage impressing means including a power source for impressing a bias voltage of the same charge as the electrostatic latent image on a portion of the electrically conducting material layer of the transfer-printing sheet, which voltage impressing means is disposed in a position immediately beyond that at which the dielectric layer of the transferprinting sheet is stripped off from the dielectric layer of the image forming member whereby soiling of the trailing end portion of the transfer-printing sheet due to overcharging can be prevented.
Claim 2
Dependent Claim 175 words
In an electrophotographic reproduction device of the transfer-printing type in which an electrostatic latent image is formed on the dielectric surface of an image forming member having a dielectric layer on an electrically conducting material layer, and the dielectric surface of a transfer-printing sheet having a dielectric layer provided on an electrically conducting material layer is brought into intimate contact with the electrostatic latent image bearing surface of the image forming member and then stripped off to effect transfer-printing of the electrostatic latent image on the transfer-printing sheet, the improvement comprising voltage impressing means including a power source for impressing a bias voltage of the same charge as the electrostatic latent image on a portion of the electrically conducting material layer of the transfer-printing sheet, which voltage impressing means is disposed in a position immediately beyond that at which the dielectric layer of the transferprinting sheet is stripped off from the dielectric layer of the image forming member whereby soiling of the trailing end portion of the transfer-printing sheet due to overcharging can be prevented.
Claim 3
Dependent Claim 27 words
A device as set forth in claim 1 in which said voltage impressing means comprises a transfer-printing sheet conveying electrically conducting roller connected to said power source.
Claim 4
Dependent Claim 25 words
A device as set forth in claim 1 in which said voltage impressing means comprises a transfer-printing sheet guide plate of an electrically conducting material.
Claim 5
Dependent Claim 20 words
A device as set forth in claim 2 wherein said transfer-printing sheet conveying electrically conducting roller is made of metal.
Claim 6
Dependent Claim 23 words
A device as set forth in claim 2 in which said transfer-printing sheet conveying electrically conducting roller is made of electrically conducting rubber.
Claim 7
Dependent Claim 19 words
A device as set forth in claim 3 in which said transfer-printing sheet guide plate is made of metal.

References Cited (Backward Citations)

US3240596A Cited
US3147679A Cited
US3345925A Cited
US3630608A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-06-17 1977-12-17 1978-06-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-06-17 1981-12-17 1982-06-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-06-17 1985-12-17 1986-06-18 $7700.00 Window Closed / Lapsed

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