Patent EP0554114A2 successfully refreshed from Google Patents.
EP0554114A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Charging member, charging device, process cartridge and image forming apparatus
Assignee: Canon Inc
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Filing: 1993-01-29
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Granted: —
•
Expires: 2013-01-29
Abstract
Abstract A charging member (2) contactable to a member (1) to be charged to electrically charge it includes a charging portion (2c) contactable to the member to be charged; a supporting portion (2b,c) for supporting the charging portion, the supporting portion including an elastic layer (2b) and a supporting member (2c) for supporting the elastic layer; wherein the charging portion is movable toward and away from the supporting portion, and an inside diameter of the charging portion is larger than an outside diameter of the supporting portion.
Inventors
- 👤 Hiroki C/O Canon Kabushiki Kaisha Kisu
- 👤 Masaharu C/O Canon Kabushiki Kaisha Ohkubo
- 👤 Kazushige C/O Canon Kabushiki Kaisha Sakurai
- 👤 Michihito C/O Canon Kabushiki Kaisha Yamazaki
- 👤 Erika C/O Canon Kabushiki Kaisha Asano
- 👤 Yasushi c/o Canon Kabushiki Kaisha Shimizu
- 👤 Hiroaki C/O Canon Kabushiki Kaisha Ogata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 00:58
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0233; Y; Y10; Y10T; Y10T428/00; Y10T428/25
Claims Analysis
Total Claims: 53
Claim 1
Independent Claim
80 words
A charging member contactable to a member to be charged to electrically charge it, comprising: a charging portion contactable to the member to be charged; a supporting portion for supporting said charging portion, said supporting portion including an elastic layer and a supporting member for supporting the elastic layer; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 2
Dependent Claim
86 words
A charging device for charging a member to be charged, comprising: a charging member including a charging member having a charging portion contactable to the member to be charged and a supporting portion for supporting the charging portion, wherein said supporting portion including an elastic layer and a supporting member for supporting the elastic layer; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 3
Dependent Claim
99 words
A process cartridge detachably mountable to an image forming apparatus, comprising: an image bearing member; a charging member contactable to said image bearing member to charge said image bearing member, said charging member including a charging portion contactable to said image bearing member and a supporting portion for supporting the charging portion, said supporting portion including an elastic layer and a supporting member for supporting the elastic layer; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 4
Dependent Claim
27 words
A process cartridge according to Claim 3, wherein said process cartridge includes developing means for developing a latent image formed on said image bearing member with toner.
Claim 5
Dependent Claim
93 words
An image forming apparatus, comprising: an image bearing member; a charging member contactable to said image bearing member to charge said image bearing member, said charging member including a charging portion contactable to said image bearing member and a supporting portion for supporting the charging portion, said supporting portion including an elastic layer and a supporting member for supporting the elastic layer; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 6
Dependent Claim
14 words
An apparatus according to Claim 5, wherein said charging member is a rotatable member.
Claim 7
Dependent Claim
16 words
An apparatus according.to Claim 6, wherein said charging portion is in the form of a tube.
Claim 8
Dependent Claim
14 words
An apparatus according to Claim 5, wherein said elastic layer is of sponge material.
Claim 9
Dependent Claim
42 words
An apparatus according to Claim 5 or 7, wherein said charging portion includes a conductive layer and a high resistance layer having a volume resistivity larger than the conductive layer in the order named in a direction toward said image bearing member.
Claim 10
Dependent Claim
17 words
An apparatus according to Claim 5, wherein said charging member is in the form of a blade.
Claim 11
Dependent Claim
43 words
An apparatus according to Claim 6, wherein 2 < d/t < 500 is satisfied where t is a thickness of said charging portion, and d is a distance from a rotational axis of said charging member to a surface of said supporting portion.
Claim 12
Dependent Claim
12 words
An apparatus according to Claim 11, wherein 10 < d/t < 200.
Claim 13
Dependent Claim
31 words
An apparatus according to Claim 5, wherein VH/VT > 0.3, where VT is a volume of said charging member, and VH is a volume of a cavity in said charging member.
Claim 14
Dependent Claim
10 words
An apparatus according to Claim 13, wherein VH/VT > 0.4.
Claim 15
Dependent Claim
16 words
An apparatus according to Claim 5, wherein said charging member is supplied with an oscillating voltage.
Claim 16
Dependent Claim
24 words
An apparatus according to Claim 15, wherein a frequency f of the oscillating voltage satisfies: f < 1500 Hz, or f > 2000 Hz.
Claim 17
Dependent Claim
16 words
An apparatus according to Claim 16, wherein f < 1000 Hz, or f > 2500 Hz.
Claim 18
Dependent Claim
23 words
An apparatus according to Claim 5, wherein an Asker-C hardness K of said charging member satisfies: 3 degrees < k < 70 degrees.
Claim 19
Dependent Claim
14 words
An apparatus according to Claim 18, wherein 5 degrees < k < 60 degrees.
Claim 20
Dependent Claim
26 words
An apparatus according to Claim 5, wherein an outer diameter of said charging member increases toward a longitudinal center thereof from each of longitudinal ends thereof.
Claim 21
Dependent Claim
27 words
An apparatus according to Claim 20, wherein the diameter at the central portion is larger than that at the end portion by not more than 2 %.
Claim 22
Dependent Claim
29 words
An apparatus according to Claim 15, wherein said oscillating voltage has a peak-to-peak voltage which is not less than twice a charge starting voltage for said image bearing member.
Claim 23
Dependent Claim
18 words
An apparatus according to Claim 15 or 22, wherein said oscillating voltage is an AC biased DC voltage.
Claim 24
Dependent Claim
35 words
An apparatus according to Claim 5, further comprising a limiting member, adjacent a longitudinal end of said charging member, for limiting relative movement in the longitudinal direction between said charging portion and said supporting portion.
Claim 25
Dependent Claim
22 words
An apparatus according to Claim 5, wherein said charging portion and said supporting portion are bonded with each other at a part.
Claim 26
Dependent Claim
42 words
An apparatus according to Claim 25, wherein a ratio w of an area where said charging portion and said supporting portion are not,contacted with each other to an area where they are faced or contacted with each other, satisfies: w ≧ 0.2.
Claim 27
Dependent Claim
89 words
A charging member contactable to a member to be charged to electrically charge it, comprising: a charging portion contactable to the member to be charged, said charging portion including a surface layer contactable to the member to be charged and an elastic layer at a backside of said surface layer; a supporting portion for supporting said charging member; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 28
Dependent Claim
89 words
A charging device for charging a member to be charged, comprising: a charging member contactable to the member to be charged to electrically charge it said charging member including a surface layer contactable to the member to be charged and an elastic layer at a backside of said surface layer; a supporting portion for supporting said charging portion; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 29
Dependent Claim
99 words
A process cartridge detachably mountable to an image forming apparatus, comprising: an image bearing member; a charging member contactable to said image bearing member to electrically charge said image bearing member, said charging member including a surface layer contactable to the member to be charged and a charging portion having an elastic layer at a backside of said surface layer; a supporting portion for supporting said charging part; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 30
Dependent Claim
26 words
An apparatus according to Claim 29, wherein said process cartridge includes developing means for developing a latent image formed on said image bearing member with toner.
Claim 31
Dependent Claim
93 words
An image forming apparatus, comprising: an image bearing member; a charging member contactable to said image bearing member to electrically charge said image bearing member, said charging member including a surface layer contactable to the member to be charged and a charging portion having an elastic layer at a backside of said surface layer; a supporting portion for supporting said charging part; wherein said charging portion is movable toward and away from said supporting portion, and an inside diameter of said charging portion is larger than an outside diameter of said supporting portion.
Claim 32
Dependent Claim
14 words
An apparatus according to Claim 31, wherein said charging member is a rotatable member.
Claim 33
Dependent Claim
17 words
An apparatus according to Claim 32, wherein said charging portion is in the form of a tube.
Claim 34
Dependent Claim
14 words
An apparatus according to Claim 31, wherein said elastic layer is of sponge material.
Claim 35
Dependent Claim
42 words
An apparatus according to Claim 31 or 33, wherein said charging portion includes a conductive layer and a high resistance layer having a volume resistivity larger than the conductive layer in the order named in a direction toward said image bearing member.
Claim 36
Dependent Claim
17 words
An apparatus according to Claim 31, wherein said charging member is in the form of a blade.
Claim 37
Dependent Claim
43 words
An apparatus according to Claim 32, wherein 2 < d/t < 500 is satisfied where t is a thickness of said charging portion, and d is a distance from a rotational axis of said charging member to a surface of said supporting portion.
Claim 38
Dependent Claim
12 words
An apparatus according to Claim 37, wherein 10 < d/t < 200.
Claim 39
Dependent Claim
31 words
An apparatus according to Claim 31, wherein VH/VT > 0.3, where VT is a volume of said charging member, and VH is a volume of a cavity in said charging member.
Claim 40
Dependent Claim
10 words
An apparatus according to Claim 39, wherein VH/VT > 0.4.
Claim 41
Dependent Claim
16 words
An apparatus according to Claim 31, wherein said charging member is supplied with an oscillating voltage.
Claim 42
Dependent Claim
24 words
An apparatus according to Claim 41, wherein a frequency f of the oscillating voltage satisfies: f < 1500 Hz, or f > 2000 Hz.
Claim 43
Dependent Claim
16 words
An apparatus according to Claim 42, wherein f < 1000 Hz, or f > 2500 Hz.
Claim 44
Dependent Claim
23 words
An apparatus according to Claim 31, wherein an Asker-C hardness K of said charging member satisfies: 3 degrees < k < 70 degrees.
Claim 45
Dependent Claim
14 words
An apparatus according to Claim 44, wherein 5 degrees < k < 60 degrees.
Claim 46
Dependent Claim
26 words
An apparatus according to Claim 31, wherein an outer diameter of said charging member increases toward a longitudinal center thereof from each of longitudinal ends thereof.
Claim 47
Dependent Claim
27 words
An apparatus according to Claim 46, wherein the diameter at the central portion is larger than that at the end portion by not more than 2 %.
Claim 48
Dependent Claim
29 words
An apparatus according to Claim 41, wherein said oscillating voltage has a peak-to-peak voltage which is not less than twice a charge starting voltage for said image bearing member.
Claim 49
Dependent Claim
18 words
An apparatus according to Claim 41 or 48, wherein said oscillating voltage is an AC biased DC voltage.
Claim 50
Dependent Claim
35 words
An apparatus according to Claim 31, further comprising a limiting member, adjacent a longitudinal end of said charging member, for limiting relative movement in the longitudinal direction between said charging portion and said supporting portion.
Claim 51
Dependent Claim
22 words
An apparatus according to Claim 31, wherein said charging portion and said supporting portion are bonded with each other at a part.
Claim 52
Dependent Claim
43 words
An apparatus according to Claim 51, wherein a ratio w of an area where said charging portion and said supporting portion are not contacted with each other to an area where they are faced or contacted with each other, satisfies: w ≧ 0.2
Claim 53
Dependent Claim
55 words
A charging member for an electrophotographic apparatus comprising a charging portion contactable to the member to be charged; and a supporting portion for supporting said charging portion, said supporting portion including an elastic layer and a supporting member for supporting the elastic layer; wherein said supporting portion is disposed with clearance within said charging portion.
References Cited (Backward Citations)
No citation records indexed.
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