EP0474220A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Charging device
Assignee: Konica Minolta Inc
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Filing: 1991-09-04
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Granted: —
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Expires: 2011-09-04
Abstract
Abstract The invention provides an apparatus for charging an imaging surface of photoreceptor. The apparatus forms a magnetic brush on a cylinder facing with a space the photoreceptor by a magnet disposed in the cylinder. The cylinder and the magnet are relatively rotatable to each other so that the magnetic brush moves around the cylinder and comes in contact with the imaging surface of the photoreceptor. An electric bias source is provided to apply an electric bias voltage superimposed DC bias voltage and AC bias voltage betweeen the imaging surface of the photoreceptor and the cylinder, whereby the imaging surface is charged by the magnetic brush under the electric bias voltage.
Inventors
- 👤 Satoshi Konica Corporation Haneda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 12:05
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; G03G15/0241; G03G21/00; G03G21/0005; G03G21/0047; G03G2215/00; G03G2215/02; G03G2215/021; G03G2215/022; G03G2221/00; G03G2221/0005
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
147 words
An apparatus for charging an imaging surface of an image carrying member which rotates in a given direction, comprising: brush means for forming a magnetic brush, said brush means including a cylinder member facing with a space said imaging surface of said image carrying member, and a magnet member disposed in said cylinder member, for attracting magnetic particles on said cylinder member to form said magnetic brush, said cylinder member and said magnet member relatively rotatable to each other so that said magnetic brush moves around said cylinder member and comes in contact with said imaging surface of said image carrying member; and bias means for applying an electric bias voltage superimposed DC bias voltage and AC bias voltage betweeen said imaging surface of said image carrying member and said cylinder member; wherein said imaging surface is charged by said magnetic brush under said electric bias voltage.
Claim 2
Independent Claim
147 words
An apparatus for charging an imaging surface of an image carrying member which rotates in a given direction, comprising: brush means for forming a magnetic brush, said brush means including a cylinder member facing with a space said imaging surface of said image carrying member, and a magnet member disposed in said cylinder member, for attracting magnetic particles on said cylinder member to form said magnetic brush, said cylinder member and said magnet member relatively rotatable to each other so that said magnetic brush moves around said cylinder member and comes in contact with said imaging surface of said image carrying member; and bias means for applying an electric bias voltage superimposed DC bias voltage and AC bias voltage betweeen said imaging surface of said image carrying member and said cylinder member; wherein said imaging surface is charged by said magnetic brush under said electric bias voltage.
Claim 3
Dependent Claim
202 words
An image forming apparatus, comprising: an image carrying member having an imaging surface rotating in a given direction; brush means for forming a magnetic brush, said brush means including a cylinder member facing with a space said imaging surface of said image carrying member, and a magnet member disposed in said cylinder member, for attracting magnetic particles on said cylinder member to form said magnetic brush, said cylinder member and said magnet member relatively rotatable to each other so that said magnetic brush moves around said cylinder member and comes in contact with said imaging surface of said image carrying member; bias means for applying an electric bias voltage betweeen said imaging surface of said image carrying member and said cylinder member, wherein said imaging surface is charged by said magnetic brush under said electric bias voltage; means for forming toner image on said charged imaging surface of said image carrying member; means for transferring said toner image from said imaging surface to a recording medium; said brush means cleaning a remaining toner on said imaging surface by said magnetic brush after said toner image has been transferred to said recording medium, and charging said cleaned imaging surface by said magnetic brush.
Claim 4
Dependent Claim
202 words
An image forming apparatus, comprising: an image carrying member having an imaging surface rotating in a given direction; brush means for forming a magnetic brush, said brush means including a cylinder member facing with a space said imaging surface of said image carrying member, and a magnet member disposed in said cylinder member, for attracting magnetic particles on said cylinder member to form said magnetic brush, said cylinder member and said magnet member relatively rotatable to each other so that said magnetic brush moves around said cylinder member and comes in contact with said imaging surface of said image carrying member; bias means for applying an electric bias voltage betweeen said imaging surface of said image carrying member and said cylinder member, wherein said imaging surface is charged by said magnetic brush under said electric bias voltage; means for forming toner image on said charged imaging surface of said image carrying member; means for transferring said toner image from said imaging surface to a recording medium; said brush means cleaning a remaining toner on said imaging surface by said magnetic brush after said toner image has been transferred to said recording medium, and charging said cleaned imaging surface by said magnetic brush.
Claim 5
Dependent Claim
18 words
The apparatus of claim 2, wherein said electric bias voltage includes DC bias voltage and AC bias voltage.
Claim 6
Dependent Claim
44 words
The apparatus of claim 2, wherein, for a brush cleaning that toner is removed from said magnetic brush, said bias means applies a DC voltage having a polarity reverse to the polarity of said DC bias voltage used when a toner image is formed.
Claim 7
Dependent Claim
16 words
The apparatus of claim 4, wherein said brush cleaning is carried out during non-image forming period.
Claim 8
Dependent Claim
39 words
The apparatus of claim 4, wherein said imaging surface having an image forming area and a non-image forming area, and wherein said brush cleaning is carried out when said magnetic brush comed in contact with said non-image forming area.
References Cited (Backward Citations)
No citation records indexed.
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