Patent US3847478A successfully refreshed from Google Patents.
US3847478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Segmented bias roll
Assignee: Xerox Corp
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Filing: 1973-12-17
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Granted: 1974-11-12
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Expires: 1993-12-17
Abstract
Abstract A bias roll xerographic transfer system for simultaneous single pass duplex copying is disclosed. The transfer roll is provided with multiple, discrete (segmented), conductive areas. In the transfer nip area the transfer bias potential is applied through a sliding contact to only the conductive segments which are in that area. A grounding brush contacts different conductive segments in separate image charging and cleaning areas, both spaced from the transfer nip. The surface of the transfer roll, with a toner image thereon, is independently corona charged in the image charging area. Thus, the transfer and image charging functions are independent. The image charging corona means may be switched between D.C. and A.C. outputs in response to movement of the transfer roll to effect image reversal or neutralization, respectively.
Inventors
- 👤 E Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:11
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/23; G03G15/231; G03G15/232; G03G15/14; G03G15/16; G03G15/1665; G03G15/167
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
204 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; anD selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means includes A.C. and D.C. corona charging means and switching means for switching between said A.C. and D.C. corona charging means in coordination with movement of said transfer member; where said D.C. corona charging means is for polarity reversal of said one image and said A.C. corona charging means is for charge neutralizing.
Claim 2
Dependent Claim
204 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; anD selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means includes A.C. and D.C. corona charging means and switching means for switching between said A.C. and D.C. corona charging means in coordination with movement of said transfer member; where said D.C. corona charging means is for polarity reversal of said one image and said A.C. corona charging means is for charge neutralizing.
Claim 3
Dependent Claim
26 words
The electrostatographic system of claim 1 further including grounding means for grounding a selected number of said conductive strips which are adjacent said corona charging means.
Claim 4
Dependent Claim
192 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable imaging charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means comprises a single corona charging apparatus and A.C. and D.C. corona power supplies and switch means for selectively connecting said corona power supplies for selecting between image polarity reversal and charge neutralizing in coordination with movement of said transfer member.
Claim 5
Dependent Claim
192 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable imaging charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means comprises a single corona charging apparatus and A.C. and D.C. corona power supplies and switch means for selectively connecting said corona power supplies for selecting between image polarity reversal and charge neutralizing in coordination with movement of said transfer member.
Claim 6
Dependent Claim
167 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; further including grounding means for grounding a selected member of said conductive strips which are adjacent said image charging means.
Claim 7
Dependent Claim
167 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; further including grounding means for grounding a selected member of said conductive strips which are adjacent said image charging means.
Claim 8
Dependent Claim
191 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging meanS for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said images comprise charged toner particles, and further including cleaning means substantially spaced away from said transfer nip for cleaning said image receiving surface and grounding means for grounding conductive strips which are adjacent said cleaning means and adjacent said image charging means.
Claim 9
Dependent Claim
191 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging meanS for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said images comprise charged toner particles, and further including cleaning means substantially spaced away from said transfer nip for cleaning said image receiving surface and grounding means for grounding conductive strips which are adjacent said cleaning means and adjacent said image charging means.
Claim 10
Dependent Claim
256 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means includes A.C. and D.C. corona charging means and switching means for switching between said A.C. and D.C. corona charging means in coordination with movement of said transfer member, where said D.C. corona charging means is for polarity reversal of said one image and said A.C. corona charging means is for charge neutralizing, wherein said one image comprises charged toner particles; and further including cleaning means substantially spaced away from said transfer nip for cleaning said image receiving surface and grounding means for grounding conductive strips which are adjacent said cleaning means and also for grounding conductive strips which are adjacent said corona charging means.
Claim 11
Dependent Claim
256 words
In an electrostatographic duplex copying system, wherein one image is transferred from an imaging surface to a transfer member and then is subsequently retransferred to a final support surface at a transfer nip, and wherein another image is transferred from an imaging surface to said same final support surface by said same transfer member: wherein said transfer member has an image receiving surface and a multiplicity of electrically discrete conductive strips underlying said image receiving surface; transfer bias means for applying an electrical transfer bias to selected ones of said conductive strips only adjacent said transfer nip for said image transfer to said final support surface; and selectively operable image charging means for selectively applying an electrical charge to said image receiving surface of said transfer member, at a charging area of said surface substantially spaced away from said transfer nip, independently of said transfer bias means; wherein said image charging means includes A.C. and D.C. corona charging means and switching means for switching between said A.C. and D.C. corona charging means in coordination with movement of said transfer member, where said D.C. corona charging means is for polarity reversal of said one image and said A.C. corona charging means is for charge neutralizing, wherein said one image comprises charged toner particles; and further including cleaning means substantially spaced away from said transfer nip for cleaning said image receiving surface and grounding means for grounding conductive strips which are adjacent said cleaning means and also for grounding conductive strips which are adjacent said corona charging means.
References Cited (Backward Citations)
US3318212A
Cited
US3684364A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-11 | 1978-05-13 | 1978-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-11 | 1982-05-13 | 1982-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-11 | 1986-05-13 | 1986-11-12 | $7700.00 | Window Closed / Lapsed |