US3944356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Charging apparatus
Assignee: Xerox Corp
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Filing: 1974-08-29
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Granted: 1976-03-16
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Expires: 1994-08-29
Abstract
Abstract An apparatus adapted to charge an image bearing member to a substantially uniform potential. The apparatus controls the area of the surface charged on the image bearing member so that it corresponds substantially in size to that of a sheet of support material arranged to have a copy of an original document reproduced thereon.
Inventors
- 👤 Thomas F. Hayne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:31
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0275
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
102 words
An apparatus for forming a charged area on an image bearing member corresponding substantially in size to the surface area of a sheet of support material arranged to have a copy of an original document reproduced thereon, including: means for detecting the size of the surface area of the sheet of support material; means for charging the image bearing member to a substantially uniform level; and means, responsive to said detecting means, for controlling said charging means so that the charged surface area of the image bearing member corresponds substantially in size to the surface area of the sheet of support material.
Claim 2
Independent Claim
102 words
An apparatus for forming a charged area on an image bearing member corresponding substantially in size to the surface area of a sheet of support material arranged to have a copy of an original document reproduced thereon, including: means for detecting the size of the surface area of the sheet of support material; means for charging the image bearing member to a substantially uniform level; and means, responsive to said detecting means, for controlling said charging means so that the charged surface area of the image bearing member corresponds substantially in size to the surface area of the sheet of support material.
Claim 3
Dependent Claim
72 words
An apparatus as recited in claim 1, wherein said detecting means includes: a base plate adapted to support a stack of support material thereon; and a plurality of switches operatively associated with said base plate, each of said plurality of switches being positioned in different locations on said base plate and being arranged to be energized by differing size of sheets of support material so as to indicate the surface area thereof.
Claim 4
Dependent Claim
75 words
An apparatus as recited in claim 2, wherein said controlling means includes: a voltage source in electrical communication with said charging means; a control voltage source electrically connected to said plurality of switches and said voltage source; and timing means, operatively associated with said control voltage source, for activating said control voltage source differing durations of time regulating the length of time said control voltage source energizes said voltage source to excite said charging means.
Claim 5
Dependent Claim
66 words
An apparatus as recited in claim 3, wherein said charging means includes: an elongated shield extending lengthwise a distance substantially the same as the width of the image bearing member, said shield defining an open ended chamber extending along the length thereof; and at least one coronode wire extended substantially in a longitudinal direction along the length of said shield in the open ended chamber thereon.
Claim 6
Dependent Claim
36 words
An apparatus as recited in claim 4, further including means for moving the image bearing member relative to said charging means in a path of movement substantially normal to the longitudinal axis of said coronode wire.
Claim 7
Dependent Claim
86 words
An apparatus as recited in claim 4, wherein said charging means further includes: a second coronode wire extending substantially parallel to said first mentioned coronode wire along the length of said shield in the open end of the chamber therein; and a plurality of spaced, substantially parallel longitudinally extending grid wires mounted in said shield partially enclosing the open end thereof with said first coronode wire being disposed therebeneath and said second coronode wire being disposed in the unenclosed portion of the chamber of said shield.
Claim 8
Dependent Claim
32 words
An apparatus as recited in claim 6, wherein said charging means further includes means for cleaning said coronode wires and the interior surface of said grid wires opposed from said coronode wires.
Claim 9
Dependent Claim
90 words
An electrophotographic printing machine of the type employing a photoconductive member to reproduce a copy of an original document on a sheet of support material, wherein the improvement includes: means for detecting the size of the surface area of the sheet of support material; means for charging the photoconductive member to a substantially uniform level; and means, responsive to said detecting means, for controlling said charging means so that the charged surface of the photoconductive member corresponds substantially in size to the surface area of the sheet of support material.
Claim 10
Dependent Claim
90 words
An electrophotographic printing machine of the type employing a photoconductive member to reproduce a copy of an original document on a sheet of support material, wherein the improvement includes: means for detecting the size of the surface area of the sheet of support material; means for charging the photoconductive member to a substantially uniform level; and means, responsive to said detecting means, for controlling said charging means so that the charged surface of the photoconductive member corresponds substantially in size to the surface area of the sheet of support material.
Claim 11
Dependent Claim
74 words
A printing machine as recited in claim 8, wherein said detecting means includes: a base plate adpated to support a stack of sheets of support material thereon; and a plurality of switches operatively associated with said base plate, each of said plurality of switches being positioned in different locations on said base plate and being arranged to be energized by differing size sheets of support material so as to indicate the surface area thereof.
Claim 12
Dependent Claim
76 words
A printing machine as recited in claim 9, wherein said controlling means includes; a voltage source in electrical communication with said charging means; a control voltage source electrically connected to said plurality of switches and said voltage source; and timing means, operatively associated with said control voltage source, for activating said control voltage source differing durations of time regulating the length of time said control voltage source energizes said voltage source to excite said charging means.
Claim 13
Dependent Claim
60 words
A printing machine as recited in claim 10, wherein said charging means includes: an elongated shield extending lengthwise a distance substantially the same as the width of the photoconductive member, said shield defining an open ended chamber extending along the length thereof; and at least one coronode wire extending substantially in a longitudinal direction along the length of said shield.
Claim 14
Dependent Claim
36 words
A printing machine as recited in claim 11, further including means for moving the photoconductive member relative to said charging means in a path of movement substantially normal to the longitudinal axis of said coronode wire.
Claim 15
Dependent Claim
87 words
A printing machine as recited in claim 11, wherein said charging means further includes: a second coronode wire extending substantially parallel to said first mentioned coronode wire along the length of said shield in the open end of the chamber therein; and a plurality of spaced substantially parallel longitudinally extending grid wires mounted in said shield partially enclosing the open end thereof with said first coronode wire being disposed therebeneath and said second coronode wire being disposed in the unenclosed portion of the chamber of said shield.
Claim 16
Dependent Claim
33 words
A printing machine as recited in claim 13, wherein said charging means further includes means for cleaning said coronode wires and the interior surface of said grid wires opposed from said coronode wires.
Claim 17
Independent Claim
83 words
A method of copying an original document on a sheet of support material, including the steps of: charging a photoconductive member to a substantially uniform potential; controlling said step of charging so that the surface area charged on the photoconductive member corresponds substantially in size to the surface area of the sheet of support material; and exposing the charged surface area of the photoconductive member to a light image of the original document recording an electrostatic latent image of the original document thereon.
Claim 18
Independent Claim
83 words
A method of copying an original document on a sheet of support material, including the steps of: charging a photoconductive member to a substantially uniform potential; controlling said step of charging so that the surface area charged on the photoconductive member corresponds substantially in size to the surface area of the sheet of support material; and exposing the charged surface area of the photoconductive member to a light image of the original document recording an electrostatic latent image of the original document thereon.
Claim 19
Dependent Claim
28 words
A method as recited in claim 15, further including the step of moving the photoconductive member relative to a substantially stationary charging device extending across the width thereof.
Claim 20
Dependent Claim
65 words
A method as recited in claim 16, wherein said step of controlling includes the steps of: detecting the surface area of the sheet of support material; and regulating the duration of time that the charging device charges the photoconductive member as the photoconductive member passes therebeneath so that the charged surface area therein corresponds substantially in size to that of the sheet of support material.
Claim 21
Dependent Claim
59 words
A method as recited in claim 17, further including the steps of: developing the electrostatic latent image with toner particles to form a toner powder image on the photoconductive member; transferring the toner powder image from the photoconductive member to a sheet of support material; and affixing substantially permanently the toner powder image to the sheet of support material.
Claim 22
Dependent Claim
41 words
A method as recited in claim 18, further including the step of repeating said steps of charging, controlling, exposing, developing and transferring to form a multi-color toner powder image on the sheet of support material prior to said step of affixing.
References Cited (Backward Citations)
US3352218A
Cited
US3503677A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-16 | 1979-09-15 | 1980-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-16 | 1983-09-15 | 1984-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-16 | 1987-09-15 | 1988-03-16 | $7700.00 | Window Closed / Lapsed |