US4669861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic recording apparatus
Assignee: Sharp Corp
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Filing: 1985-06-26
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Granted: 1987-06-02
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Expires: 2005-06-26
Abstract
Abstract An electrophotographic recording apparatus which repeats the development of an electrostatic latent image corresponding to the original, which is formed once on an image supporting means, with a toner and the succeeding transfer of the resulting toner image to a transfer substance, thereby producing a number of copies of the original, wherein said recording apparatus comprises a transferring means having at least one corona charger connected to a high AC voltage source to repeatedly conduct transfer and discharge, regions in which said transfer and said discharge are carried out, respectively, being adjacent to each other.
Inventors
- 👤 Etsuzi Nukushina
- 👤 Takao Tagawa
- 👤 Yoshiyuki Nakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:01
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/163; G03G15/1635; G03G15/1645
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
143 words
An electrophotographic recording apparatus which repeats the development of an electrostatic latent image corresponding to the original, which is formed once on an image supporting means, with a toner and the succeeding transfer of the resulting toner image to a transfer substance, thereby producing a number of copies of the original, wherein said recording apparatus comprises a transferring means having at least one corona charger and at least one regulation means, said corona charger being connected to a high AC voltage source to repeatedly conduct transfer and discharge, regions in which said transfer and said discharge are carried out, respectively, being adjacent to each other, said regulation means controlling the transfer efficiency of said transferring means depending upon an external signal with regard to at least one of the quantity of copies, and the decrease in the surface potential of the transfer substance.
Claim 2
Dependent Claim
143 words
An electrophotographic recording apparatus which repeats the development of an electrostatic latent image corresponding to the original, which is formed once on an image supporting means, with a toner and the succeeding transfer of the resulting toner image to a transfer substance, thereby producing a number of copies of the original, wherein said recording apparatus comprises a transferring means having at least one corona charger and at least one regulation means, said corona charger being connected to a high AC voltage source to repeatedly conduct transfer and discharge, regions in which said transfer and said discharge are carried out, respectively, being adjacent to each other, said regulation means controlling the transfer efficiency of said transferring means depending upon an external signal with regard to at least one of the quantity of copies, and the decrease in the surface potential of the transfer substance.
Claim 3
Dependent Claim
54 words
An electrophotographic recording apparatus according to claim 1, wherein an AC corona generated in said transfer region contains an element having a different polarity from the charging polarity of said toner to a greater extent than the same polarity as that of said toner, and acts on the back face of said transfer substance.
Claim 4
Dependent Claim
32 words
An electrophotographic recording apparatus according to claim 1, wherein said transferring means has at least two corona chargers, said corona charges being disposed in the transfer region and the discharge region, respectively.
Claim 5
Dependent Claim
47 words
An electrophotographic recording apparatus according to claim 1, wherein said transferring means has at least two corona chargers, said corona chargers being disposed in the transfer region and the dischage region, respectively, and said regulation means is used for transfer and is disposed in the transfer region.
Claim 6
Dependent Claim
61 words
An electrophotographic recording apparatus according to claim 1, wherein said transferring means has at least two corona charges which are disposed in the transfer region and the discharge region, respectively, and at least two regulation means, one of which is used for transfer and the other of which is used for discharge, said regulation means being disposed in the transfer region.
Claim 7
Dependent Claim
40 words
An electrophotographic recording apparatus according to claim 1, wherein said transferring means has at least two regulation means, one of which is used for transfer and the other of which is used for discharge, said regulation means being controlled independently.
Claim 8
Dependent Claim
49 words
An electrophotographic recording apparatus according to claim 1, wherein for transfer of the toner image to the transfer substance, a high AC voltage having a different polarity from the charging polarity of the toner and being unsymmetrical with respect to zero voltage thereof is applied to said corona charger.
Claim 9
Dependent Claim
19 words
An electrophotographic recording apparatus according to claim 4, 5 or 6 wherein said regulation means comprises a regulation grid.
Claim 10
Dependent Claim
35 words
An electrophotographic recording apparatus according to claim 8, wherein said regulation means further comprises a selection circuit for selecting a grounding mode of said regulation grid to control the transfer efficiency of the transferring means.
Claim 11
Dependent Claim
30 words
An electrophotographic recording apparatus according to claim 9, wherein said regulation grid is grounded through a resistor or a diode selected by said selection circuit depending upon said external signal.
References Cited (Backward Citations)
US4171157A
Cited
US4341457A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |