Patent US4095980A successfully refreshed from Google Patents.
US4095980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drum cleaning method and apparatus for electrostatography
Assignee: Ricoh Co Ltd
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Filing: 1976-06-04
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Granted: 1978-06-20
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Expires: 1996-06-04
Abstract
Abstract The entire surface of a photoconductive drum is developed with a toner substance after imaging, and a copy sheet is fed into contact with the drum for transfer of the toner image thereto. If the copy sheet is smaller than the maximum image area of the drum, toner from the portion of the drum outside of the edges of the copy sheet will be transferred to transfer and separating rollers and the like to contaminate the same if not removed. The invention provides a brush which slidably contacts the exposed back surface of the copy sheet and the portion of the drum outside the edges of the copy sheet to remove the toner from this portion prior to separating the copy sheet from the drum.
Inventors
- 👤 Toyokazu Satomi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:03
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/095; G03G15/14; G03G15/16; G03G2221/00; G03G2221/0005
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
117 words
A method of electrostatography comprising the steps of: a. radiating a light image onto a photoconductive member to produce an electrostatic image thereon; b. applying a toner substance to the photoconductive member to develop the electrostatic image into a toner image; c. pressing a copy sheet against the photoconductive member to transfer the toner image to the copy sheet; d. producing relative sliding movement between the photoconductive member and a brush in such a manner that the brush slidably contacts an exposed back surface of the copy sheet and a portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and e. separating the copy sheet from the photoconductive member.
Claim 2
Independent Claim
117 words
A method of electrostatography comprising the steps of: a. radiating a light image onto a photoconductive member to produce an electrostatic image thereon; b. applying a toner substance to the photoconductive member to develop the electrostatic image into a toner image; c. pressing a copy sheet against the photoconductive member to transfer the toner image to the copy sheet; d. producing relative sliding movement between the photoconductive member and a brush in such a manner that the brush slidably contacts an exposed back surface of the copy sheet and a portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and e. separating the copy sheet from the photoconductive member.
Claim 3
Dependent Claim
39 words
A method as in claim 1, further comprising the step, performed between steps (c) and (d) of: f. applying an electric potential to the copy sheet to urge the toner substance from the photoconductive member to the copy sheet.
Claim 4
Dependent Claim
39 words
A method as in claim 1, further comprising the step, performed between steps (d) and (e), of: g. applying an electric potential to the copy sheet to urge the toner substance from the photoconductive member to the copy sheet.
Claim 5
Dependent Claim
14 words
A method as in claim 1, in which step (d) comprises grounding the brush.
Claim 6
Dependent Claim
18 words
A method as in claim 1, in which step (d) comprises applying an electric potential to the brush.
Claim 7
Dependent Claim
19 words
A method as in claim 1, in which step (d) comprises applying an alternating electric voltage to the brush.
Claim 8
Dependent Claim
23 words
A method as in claim 1, further comprising the step, performed after step (d), of: h. removing the toner substance from the brush.
Claim 9
Dependent Claim
79 words
An electrostatographic apparatus comprising: a photoconductive member; imaging means for radiating a light image onto the photoconductive member; developing means for applying a toner substance to the photoconductive member; feed means for feeding a copy sheet into contact with the photoconductive member; brush means for slidably contacting an exposed back surface of the copy sheet and a portion of the photoconductive member external of the copy sheet; and separator means for separating the copy sheet from the photoconductive member.
Claim 10
Dependent Claim
79 words
An electrostatographic apparatus comprising: a photoconductive member; imaging means for radiating a light image onto the photoconductive member; developing means for applying a toner substance to the photoconductive member; feed means for feeding a copy sheet into contact with the photoconductive member; brush means for slidably contacting an exposed back surface of the copy sheet and a portion of the photoconductive member external of the copy sheet; and separator means for separating the copy sheet from the photoconductive member.
Claim 11
Dependent Claim
33 words
An apparatus as in claim 8, further comprising transfer charging means for applying an electric potential to the copy sheet for transferring a developed image from the photoconductive member to the copy sheet.
Claim 12
Dependent Claim
32 words
An apparatus as in claim 9, in which the transfer charging means is arranged to operate on the photoconductive member and copy sheet after the feed means and before the brush means.
Claim 13
Dependent Claim
29 words
An apparatus as in claim 9, in which the transfer charging means is arranged to operate on the photoconductive member after the brush means and before the separator means.
Claim 14
Dependent Claim
16 words
An apparatus as in claim 8, in which the photoconductive member comprises a rotary photoconductive drum.
Claim 15
Dependent Claim
15 words
An apparatus as in claim 8, in which the brush means comprises a rotary brush.
Claim 16
Dependent Claim
22 words
An apparatus as in claim 13, in which the brush means further comprises means for removing toner substance from the rotary brush.
Claim 17
Dependent Claim
15 words
An apparatus as in claim 13, in which the rotary brush is a magnetic brush.
Claim 18
Dependent Claim
22 words
An apparatus as in claim 15, in which the magnetic brush comprises a non-magnetic cylinder and a magnet disposed inside the cylinder.
Claim 19
Dependent Claim
33 words
An apparatus as in claim 16, in which the brush means further comprises means for selectively positioning one of a north and a south pole of the magnet adjacent to the photoconductive member.
Claim 20
Dependent Claim
24 words
An apparatus as in claim 16, in which the brush means further comprises a rotary cylinder for removing toner substance from the magnetic brush.
Claim 21
Dependent Claim
30 words
An apparatus as in claim 18, in which the brush means further comprises a toner reservoir disposed below the rotary cylinder to retain toner substance removed from the magnetic brush.
Claim 22
Dependent Claim
25 words
An apparatus as in claim 18, in which the brush means further comprises a fixed scraper to remove the toner substance from the rotary cylinder.
Claim 23
Dependent Claim
13 words
An apparatus as in claim 8, in which the brush means is grounded.
Claim 24
Dependent Claim
18 words
An apparatus as in claim 8, further comprising means for applying an electric potential to the brush means.
Claim 25
Dependent Claim
19 words
An apparatus as in claim 8, further comprising means for applying an alternating electric voltage to the brush means.
Claim 26
Dependent Claim
28 words
An apparatus as in claim 8, further comprising means for selectively moving the brush means into and out of sliding contact with the photoconductive member and copy sheet.
Claim 27
Independent Claim
152 words
A method of electrostatography comprising the steps of: a. radiating a light image onto a photoconductive member to produce an electrostatic image thereon; b. applying a toner substance to the photoconductive member to develop the electrostatic image into a toner image; c. pressing a copy sheet against the photoconductive member to transfer the toner image to the copy sheet, said copy sheet being smaller than the maximum image area of the photoconductive member so that a portion of the photoconductive member external to the copy sheet is not contacted by the copy sheet; d. producing relative sliding movement between the photoconductive member and a brush in such a manner that the brush slidably contacts an exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and subsequently, e. separating the copy sheet from the photoconductive member.
Claim 28
Independent Claim
152 words
A method of electrostatography comprising the steps of: a. radiating a light image onto a photoconductive member to produce an electrostatic image thereon; b. applying a toner substance to the photoconductive member to develop the electrostatic image into a toner image; c. pressing a copy sheet against the photoconductive member to transfer the toner image to the copy sheet, said copy sheet being smaller than the maximum image area of the photoconductive member so that a portion of the photoconductive member external to the copy sheet is not contacted by the copy sheet; d. producing relative sliding movement between the photoconductive member and a brush in such a manner that the brush slidably contacts an exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and subsequently, e. separating the copy sheet from the photoconductive member.
Claim 29
Dependent Claim
26 words
A method as in claim 25, further comprising removing toner substance from said photoconductive member after the copy sheet has been separated from the photoconductive member.
Claim 30
Dependent Claim
16 words
A method as in claim 25, wherein toner substance is applied to the entire photoconductive member.
Claim 31
Dependent Claim
147 words
An electrostatographic apparatus comprising: a photoconductive member; imaging means for radiating a light image onto the photoconductive member; developing means for applying a toner substance to the photoconductive member; feed means for feeding a copy sheet into contact with the photoconductive member, said copy sheet being smaller than the maximum image area of the photoconductive member so that a portion of the photoconductive member external to the copy sheet is not contacted by the copy sheet; brush means for slidably contacting an exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and separator means for separating the copy sheet from the photoconductive member after said brush means has slidably contacted said exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet.
Claim 32
Dependent Claim
147 words
An electrostatographic apparatus comprising: a photoconductive member; imaging means for radiating a light image onto the photoconductive member; developing means for applying a toner substance to the photoconductive member; feed means for feeding a copy sheet into contact with the photoconductive member, said copy sheet being smaller than the maximum image area of the photoconductive member so that a portion of the photoconductive member external to the copy sheet is not contacted by the copy sheet; brush means for slidably contacting an exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet to remove toner substance from said portion; and separator means for separating the copy sheet from the photoconductive member after said brush means has slidably contacted said exposed back surface of the copy sheet and said portion of the photoconductive member external of the copy sheet.
Claim 33
Dependent Claim
29 words
An apparatus as in claim 28, further comprising cleaning means for removing toner substance from said photoconductive member after the copy sheet has been separated from the photoconductive member.
Claim 34
Dependent Claim
19 words
An apparatus as in claim 28, wherein said developing means applies the toner substance to the entire photoconductive member.
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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) | 1981-06-19 | 1981-12-19 | 1982-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-19 | 1985-12-19 | 1986-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-19 | 1989-12-19 | 1990-06-20 | $7700.00 | Window Closed / Lapsed |