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US4993829A Expired / Lapsed US ⏱️ 0.0 years remaining

Developing apparatus for an image forming apparatus

Assignee: Konica Minolta Inc
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Filing: 1989-10-23
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Granted: 1991-02-19
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Expires: 2009-10-23
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Abstract

Abstract A developing apparatus including a developer housing for holding a two-component type developer including toner and a carrier, and a toner housing holding toner to be used to replenish the developer. The developer housing and toner housing are interconnected by a passageway shaped so that toner supplied to the developing housing and the developer contained therein form an interface adjacent to the passageway, in the developer housing. By so shaping the passageway, the amount of toner added to the developer can be adequately controlled, without the use of regulating devices.

Inventors

  • 👤 Seiko Naganuma
  • 👤 Satoshi Haneda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:30
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0896; G03G15/0822; G03G15/0865; G03G15/0875; G03G15/0877; G03G15/0887; G03G15/0891; Y; Y10; Y10S; Y10S222/00; Y10S222/01

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 199 words
A developing means for a photoelectric copying apparatus wherein a developer having a volume and comprising a toner and a magnetic carrier is used, said developing means comprising: a toner housing assembly comprising a toner housing containing said toner, and a toner conveyance means within said toner housing for conveying said toner to a developer having an upper surface housing, and a developer housing assembly comprising (a) said developer housing for containing said developer, (b) a rotating developing sleeve having a plurality of magnetic poles therein for supplying said toner to a photoreceptor to develop a latent image formed thereon, (c) a developer circulation means for mixing and circulating said toner and said magnetic carrier in said developer housing, and (d) a passageway between said toner housing and said developer housing through which toner can be supplied to said developer housing from said toner housing, said passageway being narrower than the upper surface of said developer housing and shaped so that toner supplied from said toner housing, when the volume of developer in said developer housing is reduced, forms a distinct layer on top of said developer in said developer housing, without mixing, in an area adjacent said passageway.
Claim 2
Dependent Claim 199 words
A developing means for a photoelectric copying apparatus wherein a developer having a volume and comprising a toner and a magnetic carrier is used, said developing means comprising: a toner housing assembly comprising a toner housing containing said toner, and a toner conveyance means within said toner housing for conveying said toner to a developer having an upper surface housing, and a developer housing assembly comprising (a) said developer housing for containing said developer, (b) a rotating developing sleeve having a plurality of magnetic poles therein for supplying said toner to a photoreceptor to develop a latent image formed thereon, (c) a developer circulation means for mixing and circulating said toner and said magnetic carrier in said developer housing, and (d) a passageway between said toner housing and said developer housing through which toner can be supplied to said developer housing from said toner housing, said passageway being narrower than the upper surface of said developer housing and shaped so that toner supplied from said toner housing, when the volume of developer in said developer housing is reduced, forms a distinct layer on top of said developer in said developer housing, without mixing, in an area adjacent said passageway.
Claim 3
Dependent Claim 18 words
The apparatus claimed in claim 1, wherein said passage member is provided directly above said developer circulation means.
Claim 4
Dependent Claim 29 words
The apparatus claimed in claim 1, wherein said passageway has a width between 5 mm and 20 mm in the direction transverse to the axis of said developing sleeve.
Claim 5
Dependent Claim 31 words
The apparatus claimed in claim 1, wherein said passageway has a length one third of that of said toner housing in the direction parallel with the axis of said developing sleeve.
Claim 6
Dependent Claim 30 words
The apparatus claimed in claim 1, wherein said passageway is provided with a protrusion member for preventing the backflow of said toner from said developer housing to said toner housing.
Claim 7
Dependent Claim 30 words
The apparatus claimed in claim 1, wherein said passageway is provided with a valve member for preventing the backflow of said toner from said developer housing to said toner housing.
Claim 8
Dependent Claim 16 words
The apparatus claimed in claim 6, wherein said valve member has an opening and closing mechanism.
Claim 9
Dependent Claim 27 words
The apparatus claimed in claim 7, wherein said valve member opens when the developing apparatus is in operation and closes when the developing apparatus is in suspension.
Claim 10
Dependent Claim 16 words
The apparatus claimed in claim 6, wherein said valve member is made of an elastic material.
Claim 11
Dependent Claim 20 words
The apparatus claimed in claim 6, wherein said valve member is a sponge roller with an opening and closing mechanism.
Claim 12
Dependent Claim 27 words
The apparatus claimed in claim 10, wherein said valve member opens when the developing apparatus is in operation and closes when the developing apparatus is in suspension.

References Cited (Backward Citations)

US3981272A Cited
JPS56153990A Cited
JPS56164064A Cited
EP0101640A2 Cited
US4601259A Cited
US4705394A Cited
US4721982A Cited
JPS62262074A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-02-18 1994-08-20 1995-02-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-02-18 1998-08-20 1999-02-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-02-18 2002-08-20 2003-02-19 $7700.00 Window Closed / Lapsed

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