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US5136311A Expired / Lapsed US ⏱️ 0.0 years remaining

Apertureless direct electrostatic printer

Assignee: Xerox Corp
•
Filing: 1990-05-21
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Granted: 1992-08-04
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Expires: 2010-05-21
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Abstract

Abstract Direct electrostatic printing without the use of an apertured printhead structure is accomplished by supplying mechanical energy in an image-wise manner via AC fringe fields coupled to a toned donor member. The A.C. fringe fields are created using paired electrodes positioned behind the donor member where they can properly function notwithstanding fluctuations in the ambient environment.

Inventors

  • 👤 Dan A. Hays

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 10:22
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/34; G03G15/344; G03G15/348; B; B41; B41J; B41J2/00; B41J2/385; B41J2/41

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 120 words
An apertureless direct electrostatic printing apparatus for forming toner images on a plain paper image receiving member, said apparatus comprising: a supply of toner; a donor belt having opposed surfaces for conveying toner on one of said opposed surfaces from said supply to a location remote from said supply; means for moving said plain paper image receiving member proximate said remote location; a plurality of electrode pairs positioned adjacent the other of said opposed surfaces; means for selectively applying an AC voltage to said plurality of electrode pairs for detaching toner from said donor member in image configuration; and means for effecting attraction of toner detached from said donor member in image configuration to said plain paper image receiving member.
Claim 2
Dependent Claim 120 words
An apertureless direct electrostatic printing apparatus for forming toner images on a plain paper image receiving member, said apparatus comprising: a supply of toner; a donor belt having opposed surfaces for conveying toner on one of said opposed surfaces from said supply to a location remote from said supply; means for moving said plain paper image receiving member proximate said remote location; a plurality of electrode pairs positioned adjacent the other of said opposed surfaces; means for selectively applying an AC voltage to said plurality of electrode pairs for detaching toner from said donor member in image configuration; and means for effecting attraction of toner detached from said donor member in image configuration to said plain paper image receiving member.
Claim 3
Dependent Claim 20 words
Apparatus according to claim 1 wherein said donor member and said image receiving member are space apart about 250 microns.
Claim 4
Dependent Claim 19 words
Apparatus according to claim 2 wherein said supply of toner comprises a two component developer and a magnetic brush.
Claim 5
Dependent Claim 36 words
Apparatus according to claim 3 wherein a positve DC voltage of approximately 200 volts is applied between said magnetic brush and a backing electrode for effecting transfer of toner to said belt donor from said supply.
Claim 6
Dependent Claim 32 words
Apparatus, according to claim 4 including a backing electrode positioned behind said image receiving member, said electrode having a negative DC voltage in the order of 100 to 500 volts applied thereto.
Claim 7
Dependent Claim 36 words
Apparatus according to claim 3 wherein a negative DC voltage of approximately 200 volts is applied between said magnetic brush and a backing electrode for effecting transfer of toner to said belt donor from said supply.
Claim 8
Dependent Claim 14 words
Apparatus accordilng to claim 6 wherein said AC voltage is approximately 300 volts peak.
Claim 9
Dependent Claim 32 words
Apparatus according to claim 7 including a backing electrode positioned behind said image receiving member, said electrode having a positive DC voltage in the order of 100 to 500 volts applied thereto.
Claim 10
Independent Claim 112 words
The method of forming toner images on a plain paper image receiving member, said method including the steps of: providing a supply of toner; using a donor belt having opposed surfaces with toner carried by one of said opposed surfaces, conveying toner from said supply to a location remote from said supply; moving a plain paper image receiving member proximate said remote location; selectively applying AC voltages to a plurality of electrode pairs positioned adjacent the other of said opposed surfaces for effecting detachment of toner from said donor member in image configuration; and effecting attraction of toner detached from said donor member in image configuration to said plain image receiving member.
Claim 11
Independent Claim 112 words
The method of forming toner images on a plain paper image receiving member, said method including the steps of: providing a supply of toner; using a donor belt having opposed surfaces with toner carried by one of said opposed surfaces, conveying toner from said supply to a location remote from said supply; moving a plain paper image receiving member proximate said remote location; selectively applying AC voltages to a plurality of electrode pairs positioned adjacent the other of said opposed surfaces for effecting detachment of toner from said donor member in image configuration; and effecting attraction of toner detached from said donor member in image configuration to said plain image receiving member.
Claim 12
Dependent Claim 21 words
The method according to claim 9 wherein said donor member and said image receiving member are spaced apart about 250 microns.
Claim 13
Dependent Claim 20 words
The method according to claim 10 wherein said supply of toner comprises a two component developer and a magnetic brush.
Claim 14
Dependent Claim 37 words
The method according to claim 11 wherein a positive DC voltage of approximately 200 volts is applied between said magnetic brush and a backing electrode for effecting transfer of toner to said belt donor from said supply.
Claim 15
Dependent Claim 33 words
The method according to claim 12 including a backing electrode positioned behind said image receiving member, said electrode having a negative DC voltage in the order of 100 to 500 volts applied thereto.
Claim 16
Dependent Claim 37 words
The method according to claim 11 wherein a negative DC voltage of approximately 200 volts is applied between said magnetic brush and a backing electrode for effecting transfer of toner to said belt donor from said supply.
Claim 17
Dependent Claim 16 words
The method according to claim 14 wherein said AC voltage is approximately 300 volts peak voltage.
Claim 18
Dependent Claim 33 words
The method according to claim 15 including a backing electrode positioned behind said image receiving member, said electrode having a positive DC voltage in the order of 100 to 500 volts applied thereto.

References Cited (Backward Citations)

US3689935A Cited
US4746939A Cited
US4491855A Cited
US4454520A Cited
US4568955A Cited
US4641955A Cited
US4755837A Cited
US4814796A Cited
US4743926A Cited
US4876561A Cited
US4860036A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-08-04 1996-02-03 1996-08-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-08-04 2000-02-03 2000-08-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-08-04 2004-02-03 2004-08-04 $7700.00 Window Closed / Lapsed

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