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US3687539A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrophotographic apparatus

Assignee: Katsuragawa Electric Co Ltd
•
Filing: 1971-06-29
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Granted: 1972-08-29
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Expires: 1991-06-29
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Abstract

Abstract In electrophotographic apparatus of the type comprising a rotary photosensitive element, a corona discharge unit for depositing a charge on the surface of the photosensitive element and an optical system for projecting an information containing light image through the corona discharge unit so as to form a latent image, the corona discharge unit and the optical system are rotated in unison about the rotary photosensitive element in a direction opposite to the direction of the rotation of the photosensitive element. The transfer printing device comprises means for bending the leading edge of a recording paper into a V shaped configuration, means for urging the recording paper against the rotary photosensitive element to transfer print a powder image onto the recording paper, a perforated suction cylinder to peel off the recording paper from the photosensitive element after transfer printing and means for admitting fluid under pressure into the space between the V shaped leading edge of the recording paper and the photosensitive element, and the cleaning device comprises a rotary brush in contact with the surface of the photosensitive element, a rotary hollow cylinder supporting the brush and provided with a plurality of perforations for supplying in from the interior of the cylinder to the brush, a stationary partition wall positioned in the hollow cylinder for dividing the interior thereof into two longitudinal compartments, a pair of corona discharge units of the opposite polarities disposed in respective compartments for ionizing the air therein, and means for supplying air under pressure into the compartments to discharge the ionized air toward the brush.

Inventors

  • 👤 Masayoshi Furuichi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 05:05
CPC Classifications
G; G03; G03G; G03G21/00; G03G21/0005; G03G21/0035; G03G15/00; G03G15/22; G03G15/28; G03G15/30; G03G2221/00; G03G2221/0005; Y; Y10; Y10S; Y10S271/00; Y10S271/90

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 105 words
In electrophotographic apparatus of the type comprising a rotary drum, a photosensitive element carried by said rotary drum, a corona discharge unit for depositing an electric charge on the surface of said photosensitive element and an optical system for projecting an information containing light image upon said photosensitive element through said corona discharge unit so as to form a latent image, the improvement which comprises means for rotating in unison said corona discharge unit and said optical system about the axis of said rotary drum in a direction opposite to the direction of rotation of said rotary drum during operation of said corona discharge unit.
Claim 2
Dependent Claim 105 words
In electrophotographic apparatus of the type comprising a rotary drum, a photosensitive element carried by said rotary drum, a corona discharge unit for depositing an electric charge on the surface of said photosensitive element and an optical system for projecting an information containing light image upon said photosensitive element through said corona discharge unit so as to form a latent image, the improvement which comprises means for rotating in unison said corona discharge unit and said optical system about the axis of said rotary drum in a direction opposite to the direction of rotation of said rotary drum during operation of said corona discharge unit.
Claim 3
Dependent Claim 45 words
The electrophotographic apparatus according to claim 1 which further comprises a stationary corona discharge unit which is operated prior to the operation of said movable corona discharge unit to deposite a charge of a polarity opposite to that deposited by said movable corona discharge device.
Claim 4
Dependent Claim 62 words
The electrophotographic apparatus according to claim 1 wherein a hollow cylinder extending in the radial direction of said rotary drum is provided between said photosensitive element and a stationary object, said movable corona discharge unit is mounted on the inner end of said hollow tube and said optical system is mounted at a point intermediate the opposite ends of said hollow tube.
Claim 5
Dependent Claim 31 words
The electrophotographic apparatus according to claim 3 wherein said hollow tube is rotated about the axis of said rotary drum at a speed corresponding to the power of magnification or reduction.
Claim 6
Dependent Claim 60 words
The electrophotographic apparatus according to claim 2 wherein said photosensitive element comprises a photoconductive layer exhibiting persistent internal polarization, a highly insulative layer bonded to one side of said photoconductive layer and an electrode layer bonded to the opposite siDe of said photoconductive layer, said photosensitive element being mounted on said rotary drum with said highly insulative layer faced outward.
Claim 7
Dependent Claim 18 words
The electrophotographic apparatus according to claim 3 wherein said hollow tube carries a lamp for illuminating said object.

References Cited (Backward Citations)

US3536483A Cited
US3540806A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-08-29 1976-02-28 1976-08-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-08-29 1980-02-28 1980-08-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-08-29 1984-02-28 1984-08-29 $7700.00 Window Closed / Lapsed

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