EP0439168A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A charger
Assignee: Canon Inc
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Filing: 1991-01-24
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Granted: —
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Expires: 2011-01-24
Abstract
Abstract A charging device for charging a moving member (1) to be charged includes a charging member (10) for contact with the member (1) to be charged; and means for applying a voltage to the charging member (10); wherein the charging member (10) has a volume resistivity of not more than 1x10⁹ ohm.cm, and a surface resistivity at a surface contactable to the member (1) to be charged not less than 5x10 ohm/cm².
Inventors
- 👤 Norihisa C/O Canon Kabushiki Kaisha Hoshika
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 14:00
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0233
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
66 words
A charging device for charging a moving member to be charged, comprising: a charging member for contact with the member to be charged; and means for applying a voltage to said charging member; wherein said charging member has a volume resistivity of not more than 1x10⁹ ohm.cm, and a surface resistivity at a surface contactable to the member to be charged not less than 5x10⁷ ohm/□.
Claim 2
Dependent Claim
21 words
A device according to Claim 1, wherein said voltage is a superposed voltage of a DC voltage and an AC voltage.
Claim 3
Dependent Claim
13 words
A device according to Claim 1, wherein said voltage is a DC voltage.
Claim 4
Dependent Claim
17 words
A device according to Claim 1, wherein said charging member is in the form of a blade.
Claim 5
Dependent Claim
29 words
A device according to Claim 1, wherein said charging member has a first layer contactable to the member to be charged and a second layer adjacent the first layer.
Claim 6
Dependent Claim
32 words
A device according to Claim 5, wherein the first layer has a surface resistivity of 5x10⁷ ohm/□ or more, and the second layer has a volume resistivity of 1x10⁹ ohm.cm or smaller.
Claim 7
Dependent Claim
14 words
A device according to Claim 1, wherein said charging member is of rubber material.
Claim 8
Dependent Claim
13 words
A device according to Claim 7, wherein the rubber material includes epichlorohydrin rubber.
Claim 9
Dependent Claim
17 words
A device according to Claim 4, wherein the member to be charged is an image bearing member.
Claim 10
Dependent Claim
16 words
A device according to Claim 9, wherein said image bearing member is a rotatable photosensitive drum.
Claim 11
Dependent Claim
18 words
A device according to Claim 10, wherein said charging member extends along an axis of said photosensitive drum.
Claim 12
Dependent Claim
18 words
A device according to Claim 4, wherein said charging member has a thickness of 1 - 3 mm.
Claim 13
Dependent Claim
25 words
A device according to Claim 10, wherein said charging member is contactable to the photosensitive drum counter-directionally with respect to a rotational movement direction thereof.
Claim 14
Dependent Claim
24 words
A device according to Claim 13, wherein an angle formed between said charging member and the photosensitive drum is not more than 30 degrees.
Claim 15
Dependent Claim
15 words
A device according to Claim 5, wherein the second layer is of a rubber material.
Claim 16
Dependent Claim
13 words
A device according to Claim 15, wherein said rubber material includes epichlorohydrin rubber.
Claim 17
Dependent Claim
15 words
A device according to Claim 5, wherein the first layer is a PTFE dispersed paint.
Claim 18
Dependent Claim
30 words
A device according to Claim 5, wherein the first layer has a thickness of 3 - 100 microns, and the second layer has a thickness of 1 - 3 microns.
Claim 19
Dependent Claim
14 words
A device according to Claim 5, wherein the first layer is of nylon resin.
Claim 20
Dependent Claim
15 words
A device according to Claim 5, wherein the first layer is of polyurethane elastomer material.
Claim 21
Dependent Claim
94 words
A charging device for charging a moving member to be charged, comprising: a charging member for contact to the member to be charged; and means for applying a voltage to said charging member; wherein said charging member has a first layer contactable to the member to be charged and a second layer adjacent to the first layer, wherein the first layer has a surface resistivity of 5x10⁷ or more ohm/□, and the second layer has a volume resistivity of 1x10⁹ ohm.cm or less; and wherein flourinated resin powder is dispersed in the first layer.
References Cited (Backward Citations)
No citation records indexed.
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