EP0338546A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Charger and image forming apparatus with same
Assignee: Canon Inc
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Filing: 1989-04-19
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Granted: —
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Expires: 2009-04-19
Abstract
Abstract A charging device (4) which is supplied with a voltage (E) and is contacted to a member (3) to be charged to electrically charge it. The voltage applied to the charging member (4) includes an AC component (E1), which is controlled to be a constant current (H), by which the member (3) to be charged can be stably and uniformly charged even if the ambient conditions are changed.
Inventors
- 👤 Hiroki Kisu
- 👤 Toshio Miyamoto
- 👤 Yohji Tomoyuki
- 👤 Junji Araya
- 👤 Shunji Nakamura
- 👤 Masanobu Saito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 12:05
CPC Classifications
G; G03; G03G; G03G13/00; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0266
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
65 words
A charging device for charging a movable member to be charged, comprising: charging means contactable to the member to be charged to charge the member to be charged; voltage application means for applying a voltage having an AC component to said charging means; and control means for controlling the AC component applied to said charging means by said voltage application means to a constant current.
Claim 2
Dependent Claim
65 words
A charging device for charging a movable member to be charged, comprising: charging means contactable to the member to be charged to charge the member to be charged; voltage application means for applying a voltage having an AC component to said charging means; and control means for controlling the AC component applied to said charging means by said voltage application means to a constant current.
Claim 3
Dependent Claim
40 words
A device according to Claim 1, wherein the voltage has a DC component, and said device further comprises second control means for controlling the DC component applied to the charging means by said voltage application means to a constant voltage.
Claim 4
Dependent Claim
18 words
A device according to Claim 1, wherein the AC component is in the form of a sine wave.
Claim 5
Dependent Claim
18 words
A device according to Claim 1, wherein the AC component is in the form of a triangular wave.
Claim 6
Dependent Claim
18 words
A device according to Claim 1, wherein the AC component is in the form of a rectangular wave.
Claim 7
Dependent Claim
40 words
A device according to Claim 1, wherein the voltage applied to the charging means includes the AC component which has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage to the member to be charged.
Claim 8
Dependent Claim
13 words
A device according to Claim 1, wherein said charging means includes a roller.
Claim 9
Dependent Claim
13 words
A device according to Claim 1, wherein said charging means includes a blade.
Claim 10
Dependent Claim
16 words
A device according to Claim 1, wherein the member to be charged is a photosensitive member.
Claim 11
Dependent Claim
101 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means having charging means contactable to said image bearing member to charge it and for forming a latent image on said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having an AC component to said charging means; and control means for controlling the AC component applied to said charging means by said voltage application means to a constant current.
Claim 12
Dependent Claim
101 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means having charging means contactable to said image bearing member to charge it and for forming a latent image on said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having an AC component to said charging means; and control means for controlling the AC component applied to said charging means by said voltage application means to a constant current.
Claim 13
Dependent Claim
40 words
An apparatus according to Claim 10, wherein the voltage has a DC component, and said apparatus further comprises second control means for controlling the DC component applied to the charging means by said voltage application means to a constant voltage.
Claim 14
Dependent Claim
18 words
An apparatus according to Claim 10, wherein the AC component is in the form of a sine wave.
Claim 15
Dependent Claim
18 words
An apparatus according to Claim 10, wherein the AC component is in the form of a triangular wave.
Claim 16
Dependent Claim
18 words
An apparatus according to Claim 10, wherein the AC component is in the form of a rectangular wave.
Claim 17
Dependent Claim
39 words
An apparatus according to Claim 10, wherein the voltage applied to the charging means includes the AC component which has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage to said image bearing member.
Claim 18
Dependent Claim
13 words
An apparatus according to Claim 10, wherein said charging means includes a roller.
Claim 19
Dependent Claim
13 words
An apparatus according to Claim 10, wherein said charging means includes a blade.
Claim 20
Dependent Claim
16 words
An apparatus according to Claim 11, wherein the member to be charged is a photosensitive member.
Claim 21
Dependent Claim
38 words
An apparatus according to Claim 10, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied by said developing means.
Claim 22
Dependent Claim
52 words
An apparatus according to Claim 18, wherein said latent image forming means includes exposure means for exposing to light a surface of said image bearing member having been charged by said charging means, and said exposure means applies to said image bearing member light corresponding to a signal indicative of image information.
Claim 23
Dependent Claim
15 words
An apparatus according to Claim 20, wherein said exposure means includes a laser beam scanner.
References Cited (Backward Citations)
No citation records indexed.
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