US3866573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic copying apparatus
Assignee: Agfa Gevaert AG
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Filing: 1972-10-24
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Granted: 1975-02-18
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Expires: 1992-10-24
Abstract
Abstract An electrostatic copying apparatus wherein the rear sides of transfer sheets are biased by a roller during transfer of powder images from an electrostatically charged xerographic surface onto the front sides of transfer sheets. The roller has a dielectric elastic outer cylindrical layer having a thickness of 0.02-0.5 millimeter, a hardness of 30-60 Shore and consisting of a polyolefine; an inner elastic cylindrical layer having a thickness of 2-10 millimeters and consisting of a polyurethane; a deformable third cylindrical layer galvanized onto the inner elastic layer, surrounded by the outer elastic layer, consisting of gold, copper, cadmium or tin and having a thickness of 0.02-2 microns; and a hollow metallic core which is surrounded by the inner elastic layer and is elastically connected with the third layer. The outer elastic layer is charged by the positive electrode of a corona discharge device which is in circuit with a source of high-voltage current. One pole of the current source is connected with the third layer by way of the core.
Inventors
- 👤 Roland Szostak
- 👤 Guenther Maurischat
- 👤 Ulrich Krekeler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:11
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/1665; G03G15/167
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
124 words
IN AN ELECTROSTATIC COPYING APPARATUS, THE COMBINATION OF TRANSPORTING MEANS ARRANGED TO ADVANCE A SERIES OF SHEETS OF TRANSFER MATERIAL ALONG A PREDETERMINED PATH TOWARD, THROUGH AND BEYOND A TRANSFER STATION; AN ELECTRICALLY CHARGED XEROGRAPHIC SURFACE LOCATED AT ONE SIDE OF SAID PATH AND ARRANGED TO TRANSPORT POWDER IMAGES TOWARD SAID TRANSFER STATION; AND A COUNTERSURFACE LOCATED AT THE OPPOSITE SIDE OF SAID PATH AND ARRANGED TO MAINTAIN SAID XEROGRAPHIC SURFACE IN IMAGE-RECEIVING CONTACT WITH SHEETS ADVANCING THROUGH SAID TRANSFER STATION, SAID COUNTERSURFACE INCLUDING A RELATIVELY THIN SHEET-CONTACTING DIELECTRIC LAYER CONSISTING OF ELASTOMERIC MATERIAL, A RELATIVELY THIN CURRENT-CONDUCTING FLEXIBLE SECOND LAYER, AND A RELATIVELY THICK THIRD LAYER CONSISTING OF ELASTOMERIC MATERIAL, SAID SECOND LAYER BEING DISPOSED BETWEEN SAID DIELECTRIC LAYER AND SAID THIRD LAYER.
Claim 2
Dependent Claim
124 words
IN AN ELECTROSTATIC COPYING APPARATUS, THE COMBINATION OF TRANSPORTING MEANS ARRANGED TO ADVANCE A SERIES OF SHEETS OF TRANSFER MATERIAL ALONG A PREDETERMINED PATH TOWARD, THROUGH AND BEYOND A TRANSFER STATION; AN ELECTRICALLY CHARGED XEROGRAPHIC SURFACE LOCATED AT ONE SIDE OF SAID PATH AND ARRANGED TO TRANSPORT POWDER IMAGES TOWARD SAID TRANSFER STATION; AND A COUNTERSURFACE LOCATED AT THE OPPOSITE SIDE OF SAID PATH AND ARRANGED TO MAINTAIN SAID XEROGRAPHIC SURFACE IN IMAGE-RECEIVING CONTACT WITH SHEETS ADVANCING THROUGH SAID TRANSFER STATION, SAID COUNTERSURFACE INCLUDING A RELATIVELY THIN SHEET-CONTACTING DIELECTRIC LAYER CONSISTING OF ELASTOMERIC MATERIAL, A RELATIVELY THIN CURRENT-CONDUCTING FLEXIBLE SECOND LAYER, AND A RELATIVELY THICK THIRD LAYER CONSISTING OF ELASTOMERIC MATERIAL, SAID SECOND LAYER BEING DISPOSED BETWEEN SAID DIELECTRIC LAYER AND SAID THIRD LAYER.
Claim 3
Dependent Claim
45 words
The combination of claim 1, further comprising corona discharge means for electrostatically charging said dielectric layer and an energy source connected in circuit with said corona discharge means and having first and second poles, said second layer being electrically connected with one of said poles.
Claim 4
Dependent Claim
51 words
The combination of claim 1, wherein said countersurface comprises a roller having a first cylindrical portion constituting said dielectric layer, a second cylindrical portion constituting said second layer, and a third cylindrical portion constituting said third layer, said first and second cylindrical portions respectively surrounding said second and third cylindrical portions.
Claim 5
Dependent Claim
27 words
The combination of claim 3, wherein said roller further comprises a core consisting at least in part of current-conducting material and surrounded by said third cylindrical portion.
Claim 6
Dependent Claim
11 words
The combination of claim 4, wherein said core is a tube.
Claim 7
Dependent Claim
15 words
The combination of claim 1, wherein said third layer has a hardness of 30-60 Shore.
Claim 8
Dependent Claim
15 words
The combination of claim 1, wherein the thickness of said third layer is 2-10 millimeters.
Claim 9
Dependent Claim
15 words
The combination of claim 1, wherein the thickness of said dielectric layer is 0.02-0.5 millimeter.
Claim 10
Dependent Claim
15 words
The combination of claim 1, wherein the thickness of said second layer is 0.02-2 microns.
Claim 11
Dependent Claim
12 words
The combination of claim 1, wherein said third layer consists of polyurethane.
Claim 12
Dependent Claim
15 words
The combination of claim 1, wherein the material of said dielectric layer is a polyolefine.
Claim 13
Dependent Claim
10 words
The combination of claim 11, wherein said polyolefine is polyethylene.
Claim 14
Dependent Claim
12 words
The combination of claim 11, wherein said polyolefine is a halogenated polyolefine.
Claim 15
Dependent Claim
12 words
The combination of claim 13, wherein said halogenated polyolefine is polyvinyl chloride.
Claim 16
Dependent Claim
19 words
The combination of claim 1, wherein said dielectric layer is a hose which is shrunk onto said second layer.
Claim 17
Dependent Claim
22 words
The combination of claim 1, wherein the dielectric constant epsilon of the material of said dielectric layer is between 2 and 6.
Claim 18
Dependent Claim
23 words
The combination of claim 1, wherein said second layer is a metal selected from the group consisting of gold, copper, cadmium and tin.
Claim 19
Dependent Claim
14 words
The combination of claim 17, wherein said metal is galvanized onto said third layer.
Claim 20
Dependent Claim
198 words
In an electrostatic copying apparatus, the combination of transporting means arranged to advance a series of sheets of transfer material along a predetermined path toward, through and beyond a transfer station; an electrostatically charged xerographic surface located at one side of said path and arranged to transport powder images toward said transfer station; and a countersurface comprising a roller located at the oppostie side of said path and arranged to maintain said xerographic surface in contact with sheets advancing through said transfer station, said roller having a relatively thin sheet-contacting first cylindrical portion constituting a dielectric layer and consisting of elastomeric material, a relatively thin flexible second cylindrical portion constituting a current-conducting second layer, and a relatively thick third cylindrical portion constituting a third layer and consisting of elastomeric material, said first and second cylindrical portions respectively surrounding said second and third cylindrical portions, and said roller further comprising a core consisting at least in part of current-conducting material and being surrounded by said third cylindrical portion, said third cylindrical portion having an axial end and said second cylindrical portion including an extension overlying said axial end of said third cylindrical portion and electrically connected with said core.
Claim 21
Dependent Claim
198 words
In an electrostatic copying apparatus, the combination of transporting means arranged to advance a series of sheets of transfer material along a predetermined path toward, through and beyond a transfer station; an electrostatically charged xerographic surface located at one side of said path and arranged to transport powder images toward said transfer station; and a countersurface comprising a roller located at the oppostie side of said path and arranged to maintain said xerographic surface in contact with sheets advancing through said transfer station, said roller having a relatively thin sheet-contacting first cylindrical portion constituting a dielectric layer and consisting of elastomeric material, a relatively thin flexible second cylindrical portion constituting a current-conducting second layer, and a relatively thick third cylindrical portion constituting a third layer and consisting of elastomeric material, said first and second cylindrical portions respectively surrounding said second and third cylindrical portions, and said roller further comprising a core consisting at least in part of current-conducting material and being surrounded by said third cylindrical portion, said third cylindrical portion having an axial end and said second cylindrical portion including an extension overlying said axial end of said third cylindrical portion and electrically connected with said core.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |