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US3697170A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic duplexing apparatus

Assignee: Xerox Corp
•
Filing: 1970-12-23
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Granted: 1972-10-10
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Expires: 1990-12-23
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Abstract

Abstract The method of producing a duplex copy by simultaneously placing images of the original subject matter to be reproduced on both sides of a sheet of final support material. A first latent electrostatic image and a second latent electrostatic image containing original input scene information are sequentially formed on a photoconductive plate and developed in the conventional xerographic manner by contacting the charged images with oppositely charged toner particles. The first image is transferred to an image storage member where the polarity of the charged toner particles making up the image is reversed. The first image, carried on the support member, is then brought adjacent to the second image on the photoreceptor surface and a sheet of final support material interposed therebetween. The two oppositely charged images are subjected to an electrostatic force of a polarity and a potential to produce simultaneously a transfer of the images to opposite sides of the final support sheet.

Inventors

  • 👤 Gopal C Bhagat
  • 👤 John M Randall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:14
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/23; G03G15/231; G03G15/232

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 189 words
The method of producing toner particle images on opposite sides of a final support member comprising forming a first toner particle image on an image retaining member with toner particles electrostatically charged to a first polarity, transferring said first image to a storage member by moving the storage and image retaining members past a transfer station where the charged toner particles are electrostatically transferred, forming a second toner particle image on an image retaining member with toner particles electrostatically charged to the first polarity with said second image being optically reversed relative to the first image, reversing the charge polarity of the particles comprising one image relative to the charge polarity of the particles comprising the other image, and simultaneously transferring charged particles of said first and second images to opposite sides of a final support member by positioning the image retaining member carrying said second image and the storage member carrying the first image on opposite sides of the final support member and moving said member past a transfer station where the charged particles from both images are electrostatically transferred to opposite sides of said final support member.
Claim 2
Independent Claim 189 words
The method of producing toner particle images on opposite sides of a final support member comprising forming a first toner particle image on an image retaining member with toner particles electrostatically charged to a first polarity, transferring said first image to a storage member by moving the storage and image retaining members past a transfer station where the charged toner particles are electrostatically transferred, forming a second toner particle image on an image retaining member with toner particles electrostatically charged to the first polarity with said second image being optically reversed relative to the first image, reversing the charge polarity of the particles comprising one image relative to the charge polarity of the particles comprising the other image, and simultaneously transferring charged particles of said first and second images to opposite sides of a final support member by positioning the image retaining member carrying said second image and the storage member carrying the first image on opposite sides of the final support member and moving said member past a transfer station where the charged particles from both images are electrostatically transferred to opposite sides of said final support member.
Claim 3
Dependent Claim 31 words
The method of claim 1 further including the step of fixing said first and second toner particle images to the opposite sides of the transfer member to which they are transferred.
Claim 4
Dependent Claim 68 words
The method of claim 1 wherein said first and second images are sequentially formed on a continuous image retaining member including a photoconductive layer, said particles comprising the first and second images have the same charge polarity when the images are formed and wherein said reversing step includes changing the charge polarity of the particles comprising the first image while the first image is on said storage member.
Claim 5
Dependent Claim 15 words
The method of claim 3 wherein said storage means includes a continuous dielectric belt member.
Claim 6
Dependent Claim 38 words
The method of claim 4 wherein said images are electrostatically transferred to opposite sides of said final support member by steps including depositing electrostatic charge on the dielectric belt surface opposite the belt surface carrying the first image.
Claim 7
Dependent Claim 51 words
The method of claim 5 wherein said transfer station includes corona generating means for depositing charge on the side of said dielectric belt opposite the side carrying an image for transferring the first image to tHe storage member and for transferring the first and second images to the final support member.
Claim 8
Dependent Claim 26 words
The method of claim 3 wherein the polarity of said first image on said storage member is reversed by spraying said image with oppositely charged corona.

References Cited (Backward Citations)

US3318212A Cited
US3506347A Cited
US3580670A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-10-10 1976-04-10 1976-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-10-10 1980-04-10 1980-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-10-10 1984-04-10 1984-10-10 $7700.00 Window Closed / Lapsed

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