Patent US3811048A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3811048A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrophotographic charging apparatus

Assignee: Xerox Corp
•
Filing: 1972-09-12
•
Granted: 1974-05-14
•
Expires: 1992-09-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A corona shield is positioned about a corona wire to shield against radiation from the wire in all but the desired direction (onto a xerographic surface). The shield members are movable in various directions relative to the corona wire so as to control intensity and direction of the corona discharge, thus to control the density of the electrostatic image on the xerographic surface.

Inventors

  • 👤 S Matsumoto
  • 👤 I Takahashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 19:07
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0291

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 98 words
A corona apparatus for use in charging a surface in an electrophotographic process, said coronA apparatus including a corona wire and a grounded, conductive concave shield member partially surrounding said corona wire, at least a part of said surface being exposed to positive corona discharge from said corona wire when a positive electrical potential is applied to said wire, adjustment means to control the intensity of the positive corona discharge from said corona wire relative to said surface, said adjustment means including means to move at least a part of said shield member relative to said corona wire.
Claim 2
Dependent Claim 98 words
A corona apparatus for use in charging a surface in an electrophotographic process, said coronA apparatus including a corona wire and a grounded, conductive concave shield member partially surrounding said corona wire, at least a part of said surface being exposed to positive corona discharge from said corona wire when a positive electrical potential is applied to said wire, adjustment means to control the intensity of the positive corona discharge from said corona wire relative to said surface, said adjustment means including means to move at least a part of said shield member relative to said corona wire.
Claim 3
Dependent Claim 46 words
A corona apparatus as defined in claim 1, wherein said means to move at least a part of said shield member relative to said corona wire comprises means to move at least part of said shield member in a direction toward and away from said surface.
Claim 4
Dependent Claim 46 words
A corona apparatus as defined in claim 1, wherein said means to move at least a part of said shield member relative to said corona wire comprises means to move at least a part of said shield member in a direction generally parallel to said surface.
Claim 5
Dependent Claim 43 words
A corona apparatus as defined in claim 1, wherein said means to move at least a part of said shield member relative to said corona wire comprises means to expand and contract the concavity of said shield member relative to said corona wire.
Claim 6
Dependent Claim 45 words
The corona apparatus of claim 1, wherein said means to move at least a part of said shield member relative to said corona wire comprises means to move at least a first part of said shield member independently of the remainder of said shield member.
Claim 7
Dependent Claim 22 words
The corona apparatus of claim 1, further including insulating means located between said corona wire and a portion of said shield member.
Claim 8
Dependent Claim 43 words
The corona apparatus of claim 1, wherein said means to move at least a part of said shield member relative to said corona wire includes a spring biased, pivoting support member and an adjusting screw for causing pivotal motion of said support member.

References Cited (Backward Citations)

US2157718A Cited
US3358289A Cited
US3566110A Cited
US3603789A Cited
US3655966A Cited
US3620617A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-05-13 1977-11-12 1978-05-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-05-13 1981-11-12 1982-05-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-05-13 1985-11-12 1986-05-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag