EP0308185A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A charging device
Assignee: Canon Inc
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Filing: 1988-09-13
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Granted: —
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Expires: 2008-09-13
Abstract
Abstract A charging device (2) for charging a moving member (1) to be charged includes charging device for being contacted to the member (1) to be charged to charge the member; a voltage source (E) for applying a vibratory voltage to the charging device; wherein the charging device includes a first layer (2c) contactable to the member to be charged, a second layer adjacent (2b) thereto wherein the first layer (2a) is a dielectric layer having a volume resistivity larger than that of the second layer.
Inventors
- 👤 Junji Araya
- 👤 Masanobu Saito
- 👤 Hiroki Kisu
- 👤 Yohji Tomoyuki
- 👤 Shunji Nakamura
- 👤 Noribumi Koitabashi
- 👤 Hiroyuki Adachi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 07:48
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0233
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
77 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a vibratory voltage to said charging means; wherein said charging means includes a contact layer contactable to the member to be charged and a further layer adjacent thereto wherein the contact layer is a dielectric layer having a volume resistivity larger than that of the further layer.
Claim 2
Dependent Claim
77 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a vibratory voltage to said charging means; wherein said charging means includes a contact layer contactable to the member to be charged and a further layer adjacent thereto wherein the contact layer is a dielectric layer having a volume resistivity larger than that of the further layer.
Claim 3
Dependent Claim
28 words
A device according to claim 1, wherein an impedance component of an electrostatic capacity of said charging means is smaller than an impedance component of a resistance thereof.
Claim 4
Dependent Claim
76 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a vibratory voltage to the charging means; wherein said charging means includes a surface dielectric contact layer at a contact portion with the member, and the impedance component of the electrostatic capacity of said charging means is smaller than the impedance component of the resistance thereof.
Claim 5
Dependent Claim
76 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a vibratory voltage to the charging means; wherein said charging means includes a surface dielectric contact layer at a contact portion with the member, and the impedance component of the electrostatic capacity of said charging means is smaller than the impedance component of the resistance thereof.
Claim 6
Dependent Claim
117 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a voltage to said charging means; wherein said charging means includes a high resistance contact layer at a portion where it is contacted to the member to be charged, and the following is satisfied: ρℓ > E²x(0.1x10⁻³)²/P (ohm.m²) where ρ is a volume resistivity (ohm.m) of the high resistance contact layer, ℓ is a thickness (m) of the high resistance contact layer, E is the voltage (V) applied by said voltage applying means, P is a capacity (W) of a voltage source of said voltage applying means.
Claim 7
Dependent Claim
117 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a voltage to said charging means; wherein said charging means includes a high resistance contact layer at a portion where it is contacted to the member to be charged, and the following is satisfied: ρℓ > E²x(0.1x10⁻³)²/P (ohm.m²) where ρ is a volume resistivity (ohm.m) of the high resistance contact layer, ℓ is a thickness (m) of the high resistance contact layer, E is the voltage (V) applied by said voltage applying means, P is a capacity (W) of a voltage source of said voltage applying means.
Claim 8
Dependent Claim
235 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a voltage to said charging means; wherein said charging means includes a high resistance contact layer at a portion where it is contacted to the member to be charged, and the following is satisfied: ρ ℓ> E²x(0.1x10⁻³)²/P (ohm.m²) where ρ is a volume resistivity (ohm.m) of the high resistance contact layer, ℓ is a thickness (m) of the high resistance contact layer, E is the voltage (V) applied by said voltage applying means, P is a capacity (W) of a voltage source of said voltage applying means; wherein R2 of said charging means at a nip between said charging means and the member to be charged and an electrostatic capacitance C2 of said charging member satisfy: where E1-V (n=∞) is a saturated voltage of said charging means, E1 is a voltage (V) applied to said charging means, C1 is an electrostatic capacity of the member to be charged at the nip, R1 is a resistance of the member to be charged at the nip, t₁ = (a width of the nip)/(a peripheral speed of said charging means) t₂ = (a peripheral length of said charging means)/(a peripheral speed of said charging means) where E1 is a charge starting voltage of the member to be charged.
Claim 9
Dependent Claim
235 words
A charging device for charging a moving member to be charged, comprising: charging means for being contacted to the member to be charged to charge the member; means for applying a voltage to said charging means; wherein said charging means includes a high resistance contact layer at a portion where it is contacted to the member to be charged, and the following is satisfied: ρ ℓ> E²x(0.1x10⁻³)²/P (ohm.m²) where ρ is a volume resistivity (ohm.m) of the high resistance contact layer, ℓ is a thickness (m) of the high resistance contact layer, E is the voltage (V) applied by said voltage applying means, P is a capacity (W) of a voltage source of said voltage applying means; wherein R2 of said charging means at a nip between said charging means and the member to be charged and an electrostatic capacitance C2 of said charging member satisfy: where E1-V (n=∞) is a saturated voltage of said charging means, E1 is a voltage (V) applied to said charging means, C1 is an electrostatic capacity of the member to be charged at the nip, R1 is a resistance of the member to be charged at the nip, t₁ = (a width of the nip)/(a peripheral speed of said charging means) t₂ = (a peripheral length of said charging means)/(a peripheral speed of said charging means) where E1 is a charge starting voltage of the member to be charged.
Claim 10
Dependent Claim
42 words
A device according to claim 4 or claim 5, wherein the high resistance contact layer is a dielectric layer, and wherein an impedance component of an electrostatic capacity of said charging means is smaller than an impedance component of a resistance thereof.
Claim 11
Independent Claim
32 words
A device according to any one of claims 2, 3 and 6, wherein the electrostatic capacity of said charging means is larger than the electrostatic capacity of the member to be charged.
Claim 12
Dependent Claim
16 words
A device according to claim 4 or claim 5, wherein said voltage is a vibratory voltage.
Claim 13
Independent Claim
22 words
A device according to any one of claims 1, 3 and 8, wherein the voltage is a superposed DC and AC voltage.
Claim 14
Independent Claim
41 words
A device according to any one of claims 1, 3, 8 and 9, wherein a peak-to-peak voltage of the vibratory voltage is not less than twice the absolute value of the charge starting voltage relative to the member to be charged.
Claim 15
Dependent Claim
42 words
A device according to claim 4 or claim 5, wherein the high resistance contact layer of said charging means includes a resin layer at a portion of contact with the member to be charged, and a rubber layer behind the resin layer.
Claim 16
Dependent Claim
28 words
A device according to claim 11, wherein a rubber layer is provided behind the high resistance contact layer, and a core member is provided behind the rubber layer.
Claim 17
Dependent Claim
18 words
A device according to claim 11, wherein a core member is provided behind the high resistance contact layer.
Claim 18
Independent Claim
20 words
A device according to any one of claims 3, 4 and 5, comprising a further layer behind the contact layer.
Claim 19
Dependent Claim
21 words
A device according to claim 1 or claim 14, wherein the further layer of said charging means is a rubber layer.
Claim 20
Dependent Claim
20 words
A device according to claim 15, wherein a core member is provided inside the further layer of said charging means.
Claim 21
Dependent Claim
21 words
A device according to claim 1 or claim 14, wherein the further layer of said charging means is a core member.
Claim 22
Independent Claim
29 words
A device according to any one of claims 1, 3, 4, 5, 14, 15, 16 and 17, wherein the contact layer of said charging means is a rubber layer.
Claim 23
Independent Claim
28 words
A device according to any one of claims 1, 3, 4, 5, 14, 15 and 16, wherein the contact layer of said charging means is a resin layer.
Claim 24
Dependent Claim
18 words
A device according to claim 19, wherein the contact layer of said charging means is of nylon resin.
Claim 25
Independent Claim
22 words
A device according to any one of the preceding claims, wherein said charging means is in the form of a rotatable roller.
Claim 26
Dependent Claim
16 words
A device according to claim 21, wherein said charging means rotates following movement of the member.
Claim 27
Independent Claim
22 words
A device according to any one of claims 1 to 20, wherein said charging means is in the form of a blade.
Claim 28
Independent Claim
21 words
A device according to any one of the preceding claims, wherein the member to be charged is an image bearing member.
Claim 29
Dependent Claim
15 words
A device according to claim 24, wherein said image bearing member is a photosensitive member.
Claim 30
Dependent Claim
35 words
A charging device for charging a moving member to be charged, comprising a first, relatively low resistivity portion, and a further, relatively high resistivity portion between the first portion and the member to be charged.
Claim 31
Dependent Claim
35 words
A charging device for charging a moving member to be charged, comprising a first, relatively low resistivity portion, and a further, relatively high resistivity portion between the first portion and the member to be charged.
References Cited (Backward Citations)
No citation records indexed.
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