US3924943A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Segmented biased transfer member
Assignee: Xerox Corp
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Filing: 1974-06-11
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Granted: 1975-12-09
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Expires: 1994-06-11
Abstract
Abstract In an electrostatographic copying system wherein an image is transferable from an image support surface to a copy utilizing an electrically biased transfer roller positionable thereagainst, the transfer roller conductive core is divided along its axis into electrically discrete cylindrical segments, and commonly covered with an electrically relaxable elastomer layer. An electrical bias circuit provides discrete electrical bias supplies for these core segments, whereby a central segment can be connected to a constant current (variable voltage) source, and end segments slaved to the voltage level on the central segment to prevent roll and leakage in no copy areas from adversely affecting the constant current source.
Inventors
- 👤 Gerald M Fletcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:18
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/1665; G03G15/167; G03G15/1685
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
63 words
An improved transfer member for transferring an image from an image support surface to a copy moved between the transfer member and support surface, the improvement comprising: at least two segments which are electrically discrete in a direction perpendicular to the direction of movement of the copy and electrical bias means for supplying discrete electrical biases to at least two of the segments.
Claim 2
Dependent Claim
63 words
An improved transfer member for transferring an image from an image support surface to a copy moved between the transfer member and support surface, the improvement comprising: at least two segments which are electrically discrete in a direction perpendicular to the direction of movement of the copy and electrical bias means for supplying discrete electrical biases to at least two of the segments.
Claim 3
Dependent Claim
114 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased transfer member positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer member wherein: said transfer member comprises at least two endless loop core segments which are electrically discrete in a direction transverse to the direction of movement of said copy, and a resistive material layer commonly overlying said segments; and electrical bias means for supplying discrete electrical biases to at least two of said segments.
Claim 4
Dependent Claim
114 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased transfer member positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer member wherein: said transfer member comprises at least two endless loop core segments which are electrically discrete in a direction transverse to the direction of movement of said copy, and a resistive material layer commonly overlying said segments; and electrical bias means for supplying discrete electrical biases to at least two of said segments.
Claim 5
Dependent Claim
52 words
The copying system of claim 2, wherein said electrical bias means provides a substantially constant current and variable voltage bias to a first one of said segments, and a non-constant current variable voltage bias to another of said segments corresponding to the variable voltage applied to said first one of said segments.
Claim 6
Dependent Claim
114 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased generally cylindrical transfer roller mounted for rotation about its longitudinal axis and positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer roller wherein: said transfer roller is divided along its axis into a plurality of electrically discrete generally cylindrical segments, and electrical bias means are connected to Said transfer roller for providing electrical bias supplies which are discrete for at least two of said segments.
Claim 7
Dependent Claim
114 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased generally cylindrical transfer roller mounted for rotation about its longitudinal axis and positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer roller wherein: said transfer roller is divided along its axis into a plurality of electrically discrete generally cylindrical segments, and electrical bias means are connected to Said transfer roller for providing electrical bias supplies which are discrete for at least two of said segments.
Claim 8
Dependent Claim
52 words
The copying system of claim 4, wherein said electrical bias means provides a substantially constant current and variable voltage bias to a first one of said segments, and a non-constant current variable voltage bias to another of said segments corresponding to the variable voltage applied to said first one of said segments.
Claim 9
Dependent Claim
25 words
The copying system of claim 4 wherein said transfer roller comprises conductive core segments insulated from one another and a commonly overlying resistive material layer.
Claim 10
Dependent Claim
123 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased generally cylindrical transfer roller mounted for rotation about its longitudinal axis and positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer roller wherein said transfer roller comprises: a conductive generally cylindrical central core; conductive end cores axially extending from opposite ends of said central core and mounted co-axially therewith, said end cores being electrically insulated from said central core; and a layer of resistive material overlying both said central core and said end cores.
Claim 11
Dependent Claim
123 words
In an electrostatographic copying system wherein an image is transferable from an image support surface to an adjacent copy utilizing an electrically biased generally cylindrical transfer roller mounted for rotation about its longitudinal axis and positioned so as to contact and keep said copy in contact with said support surface while said copy is moved between said support surface and said transfer member, the improvement in said electrically biased transfer roller wherein said transfer roller comprises: a conductive generally cylindrical central core; conductive end cores axially extending from opposite ends of said central core and mounted co-axially therewith, said end cores being electrically insulated from said central core; and a layer of resistive material overlying both said central core and said end cores.
Claim 12
Dependent Claim
32 words
The copying system of claim 7, wherein said layer of resistive material is a single monolithic generally cylindrical blanket providing a resistive electrical connection between said central core and said end cores.
Claim 13
Dependent Claim
16 words
The copying system of claim 7 wherein said resistive material is an elastomeric electrically relaxable material.
Claim 14
Dependent Claim
48 words
The copying system of claim 7 further including electrical bias means for biasing said central core with a substantially constant current and variable voltage bias, and for discretely biasing said end cores with a variable voltage maintained substantially equal to the variable voltage applied to said central core.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |