US5638159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing unit for an image forming apparatus and method of collecting bicomponent developer therefrom
Assignee: Ricoh Co Ltd
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Filing: 1995-01-26
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Granted: 1997-06-10
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Expires: 2015-01-26
Abstract
Abstract A developing unit using a bicomponent developer and capable of collecting only carrier included in the developer and deteriorated due to aging while recycling toner, and a method of collecting the developer from the developing unit. The developing unit separate the developer into toner and carrier before the collection of the developer.
Inventors
- 👤 Tsukuru Kai
- 👤 Nobuo Iwata
- 👤 Hidetoshi Yano
- 👤 Yasushi Nakazato
- 👤 Satoshi Muramatsu
- 👤 Yoshiko Ishii
- 👤 Nobuto Yokokawa
- 👤 Masako Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:57
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0844; G03G15/0887; G03G15/0891; G03G15/0893
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
97 words
A method of collecting a developer to develop images, said developer including a mixture of a toner and a carrier, comprising the steps of: separating said carrier from said developer; collecting said carrier; collecting said toner by passing said toner past an opening located upstream of said developing unit, said opening being smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing said carrier from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 2
Independent Claim
97 words
A method of collecting a developer to develop images, said developer including a mixture of a toner and a carrier, comprising the steps of: separating said carrier from said developer; collecting said carrier; collecting said toner by passing said toner past an opening located upstream of said developing unit, said opening being smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing said carrier from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 3
Dependent Claim
119 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the carrier; separating means for separating the developer into the toner and the carrier before collection of said carrier; a toner collecting portion; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing said carrier collected by said collecting means from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 4
Dependent Claim
119 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the carrier; separating means for separating the developer into the toner and the carrier before collection of said carrier; a toner collecting portion; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing said carrier collected by said collecting means from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 5
Dependent Claim
39 words
A developing unit as claimed in claim 2, further comprising charging depositing means facing a developer collecting sleeve included in said collecting means, and for depositing a charge opposite in polarity to the toner on said developer collecting sleeve.
Claim 6
Dependent Claim
34 words
A developing unit as claimed in claim 2, further comprising a carrier collecting portion for collecting the carrier separated from the toner, and a developer regulating member located upstream of said carrier collecting portion.
Claim 7
Dependent Claim
75 words
A developing unit using a developer including a mixture of a toner and a carrier, comprising: collecting means for collecting the developer; separating means for separating the developer into the toner and the carrier before collection of said developer; a toner collecting portion; and an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner.
Claim 8
Dependent Claim
75 words
A developing unit using a developer including a mixture of a toner and a carrier, comprising: collecting means for collecting the developer; separating means for separating the developer into the toner and the carrier before collection of said developer; a toner collecting portion; and an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner.
Claim 9
Dependent Claim
127 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the developer; recycling means for separating the developer into the toner and the carrier and then recycling said toner; a toner collecting portion; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing said carrier separated by said recycling means from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the developer supply and the toner is returned to the developer supply.
Claim 10
Dependent Claim
127 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the developer; recycling means for separating the developer into the toner and the carrier and then recycling said toner; a toner collecting portion; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing said carrier separated by said recycling means from a supply of developer, whereby the carrier, which may have become deteriorated due to repeated use, is removed from the developer supply and the toner is returned to the developer supply.
Claim 11
Dependent Claim
119 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the developer; a carrier collecting portion for collecting the carrier of the collected developer; a toner collecting portion for collecting the toner of the collected developer; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing the collected carrier from a supply of developer, whereby the collected carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 12
Dependent Claim
119 words
A developing unit for supplying a developer to develop images, said developer including a mixture of a toner and a carrier, said developing unit comprising: collecting means for collecting the developer; a carrier collecting portion for collecting the carrier of the collected developer; a toner collecting portion for collecting the toner of the collected developer; an opening in said developing unit located upstream of said toner collecting portion and smaller than a particle size of the carrier, but greater than a particle size of the toner; and removing means for removing the collected carrier from a supply of developer, whereby the collected carrier, which may have become deteriorated due to repeated use, is removed from the supply of developer.
Claim 13
Dependent Claim
32 words
A developing unit as claimed in claim 7, wherein said carrier collecting portion and said toner collecting portion are arranged in this order in a direction in which the developer is moved.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-06-09 | 2000-12-09 | 2001-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-09 | 2004-12-09 | 2005-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-09 | 2008-12-09 | 2009-06-10 | $7700.00 | Window Closed / Lapsed |