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US4891673A Expired / Lapsed US ⏱️ 0.0 years remaining

Development system

Assignee: Xerox Corp
•
Filing: 1988-08-04
•
Granted: 1990-01-02
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Expires: 2008-08-04
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Abstract

Abstract An apparatus which develops an electrostatic latent image recorded on a photoconductive member used in an electrophotographic printing machine. The apparatus employs a developer material which ages during the life of the electrophotographic printing machine. Carrier granules are added to the developer material to extend the life of the developer material. When the quantity of developer material exceeds a predetermined quantity, developer material exits therefrom through an exit port. A magnetic flux field is generated in the region of the exit port to form a carrier bead curtain which prevents the passage of toner particles therethrough while permitting developer material and carrier granules to exit therefrom.

Inventors

  • 👤 Kim S. Buell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 03:17
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0844; G03G13/00; G03G13/06; G03G13/08; G03G13/09

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 190 words
An apparatus for developing an electrostatic latent image used in a printing machine, including: means for transporting a developer material comprising at least carrier granules having toner particles adhering thereto into contact with the electrostatic latent image; a housing defining a chamber having a supply of developer material therein, said transporting means being in communication with the chamber of said housing for receiving developer material, said housing having an exit port located at a selected position in the chamber of said housing to enable developer material to exit from the chamber when the level of developer material therein covers at least a portion of the exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and means for sealing the exit port of said housing with a substantially impervious toner particle seal, said sealing means being previous to developer material and carrier granules so as to prevent the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.
Claim 2
Independent Claim 190 words
An apparatus for developing an electrostatic latent image used in a printing machine, including: means for transporting a developer material comprising at least carrier granules having toner particles adhering thereto into contact with the electrostatic latent image; a housing defining a chamber having a supply of developer material therein, said transporting means being in communication with the chamber of said housing for receiving developer material, said housing having an exit port located at a selected position in the chamber of said housing to enable developer material to exit from the chamber when the level of developer material therein covers at least a portion of the exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and means for sealing the exit port of said housing with a substantially impervious toner particle seal, said sealing means being previous to developer material and carrier granules so as to prevent the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.
Claim 3
Dependent Claim 56 words
An apparatus according to claim 1, wherein said sealing means includes means for generating a magnetic flux field in the region of the exit port of said housing to form a carrier bead curtain which prevents the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough.
Claim 4
Dependent Claim 49 words
An apparatus according to claim 2, wherein the ratio of toner particles to carrier granules by weight being added by said discharging means to the chamber of the housing is substantially greater than the ratio of toner particles to carrier granules by weight in the chamber of said housing.
Claim 5
Dependent Claim 22 words
An apparatus according to claim 3, wherein said generating means includes a magnetic member positioned adjacent the exit port of said housing.
Claim 6
Dependent Claim 22 words
An apparatus according to claim 4, wherein said discharging means includes means for storing a supply of carrier granules and toner particles.
Claim 7
Dependent Claim 201 words
An electorphotograhic printing machine of the type having an electrostatic latent image recorded on a photoconductive member, wherein the improvement includes: means for transporting a developer material comprising at least carrier granules having toner particles adhering thereto closely adjacent to the electrostatic latent image recorded on the photoconductive member; a housing defining a chamber having a supply of developer material therein, said transporting means being in communication with the chamber of said housing for receiving developer material, said housing having an exit port located at a selected position in the chamber of said housing to enable developer material to exit from the chamber when the level of developer material therein covers at least a portion ofthe exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and means for sealing the exit port of said housing with a substantially impervious toner particle seal, said sealing means being previous to developer material and carrier granules so as to prevent the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.
Claim 8
Dependent Claim 201 words
An electorphotograhic printing machine of the type having an electrostatic latent image recorded on a photoconductive member, wherein the improvement includes: means for transporting a developer material comprising at least carrier granules having toner particles adhering thereto closely adjacent to the electrostatic latent image recorded on the photoconductive member; a housing defining a chamber having a supply of developer material therein, said transporting means being in communication with the chamber of said housing for receiving developer material, said housing having an exit port located at a selected position in the chamber of said housing to enable developer material to exit from the chamber when the level of developer material therein covers at least a portion ofthe exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and means for sealing the exit port of said housing with a substantially impervious toner particle seal, said sealing means being previous to developer material and carrier granules so as to prevent the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.
Claim 9
Dependent Claim 57 words
A printing machine according to claim 6, wherein said sealing means includes means for generating a magnetic flux field in the region of the exit port of said housing to form a carrier bead curtain which prevents the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough.
Claim 10
Dependent Claim 50 words
A printing machine according to claim 7, wherein the ratio of toner particles to carrier granules by weight being added by said discharging means to the chamber of the housing is substantially greater than the ratio of toner particles to carrier granules by weight in the chamber of said housing.
Claim 11
Dependent Claim 23 words
A printing machine according to claim 8, wherein said generating means includes a magnetic member positioned adjacent the exit port of said housing.
Claim 12
Dependent Claim 23 words
A printing machine according to claim 9, wherein said discharging means includes means for storing a supply of carrier granules and toner particles.
Claim 13
Independent Claim 205 words
An apparatus for developing an electrostatic latent image used in a printing machine, including: a magnetic developer roller for transporting a developer material comprising at least magnetic carrier granules having toner particles adhering thereto into contact with the electrostatic latent image; a housing defining a chamber having a supply of developer material therein with at least a portion of said magnetic developer roller being located in the chamber of said housing for attracting developer material to the exterior surface thereof, said housing having an exit port located at a selected position in the chamber of said housing for enabling excessive developer material to escape from the chamber when the level of developer material therein covers at least a portion of the exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and a magnetic member mounted on said housing adjacent the exit port therein to generate a magnetic flux field to form a carrier bead curtain over the exit port which prevents the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.
Claim 14
Independent Claim 205 words
An apparatus for developing an electrostatic latent image used in a printing machine, including: a magnetic developer roller for transporting a developer material comprising at least magnetic carrier granules having toner particles adhering thereto into contact with the electrostatic latent image; a housing defining a chamber having a supply of developer material therein with at least a portion of said magnetic developer roller being located in the chamber of said housing for attracting developer material to the exterior surface thereof, said housing having an exit port located at a selected position in the chamber of said housing for enabling excessive developer material to escape from the chamber when the level of developer material therein covers at least a portion of the exit port; means for discharging toner particles and carrier granules into the chamber of said housing; and a magnetic member mounted on said housing adjacent the exit port therein to generate a magnetic flux field to form a carrier bead curtain over the exit port which prevents the passage of toner particles through the exit port while permitting the passage of developer material and carrier granules therethrough to maintain a predetermined quantity of developer material and carrier granules in the chamber of said housing.

References Cited (Backward Citations)

US4101211A Cited
US4387982A Cited
US4394086A Cited
US4697914A Cited
US4614165A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-01-01 1993-07-03 1994-01-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-01-01 1997-07-03 1998-01-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-01-01 2001-07-03 2002-01-02 $7700.00 Window Closed / Lapsed

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