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Patent US4972231A successfully refreshed from Google Patents.
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US4972231A Expired / Lapsed US ⏱️ 0.0 years remaining

Linearly movable developer unit magnet

Assignee: Xerox Corp
•
Filing: 1989-05-01
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Granted: 1990-11-20
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Expires: 2009-05-01
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Abstract

Abstract An apparatus which develops a latent image recorded on a photoconductive member with developer material. The developer material is transported by a tubular member into a development zone. Developer material is attracted to the surface of the tubular member by a stationary magnet. A movable magnet translates from an operative position, wherein the magnet generates a weak magnetic field in the development zone, and a non-operative position, wherein the magnet generates a strong magnetic field in the development zone. In the operative position, the weak magnetic field releases the developer material from the surface of the tubular member so that the latent image attracts the developer material thereto. In the non-operative position, the strong magnetic field attracts the developer material to the surface of the tubular member preventing development of the latent image.

Inventors

  • 👤 Jan Bares

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 17:04
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; G03G15/0921

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 104 words
An apparatus for developing a latent image recorded on a member with developer material, including: means for transporting the developer material into a development zone so as to develop the latent image recorded on the member with developer material; a magnet operatively associated with said transporting means to attract developer material thereto in a non-operative position and to release developer material therefrom in an operative position; and means for moving said magnet between an operative position, wherein said magnet generates a weak magnetic field in the development zone, and a non-operative position, wherein said magnet generates a strong magnet field in the development zone.
Claim 2
Independent Claim 104 words
An apparatus for developing a latent image recorded on a member with developer material, including: means for transporting the developer material into a development zone so as to develop the latent image recorded on the member with developer material; a magnet operatively associated with said transporting means to attract developer material thereto in a non-operative position and to release developer material therefrom in an operative position; and means for moving said magnet between an operative position, wherein said magnet generates a weak magnetic field in the development zone, and a non-operative position, wherein said magnet generates a strong magnet field in the development zone.
Claim 3
Dependent Claim 23 words
An apparatus according to claim 1, wherein said transporting means includes a tubular member having said magnet disposed interiorly thereof and spaced therefrom.
Claim 4
Dependent Claim 18 words
An apparatus according to claim 2, further including an arcuate magnet positioned disposed interiorly of said tubular member.
Claim 5
Dependent Claim 36 words
An apparatus according to claim 3, wherein said moving means translates said magnet between the non-operative position and the operative position with the non-operative position being adjacent the development zone and the operative position remote therefrom.
Claim 6
Dependent Claim 12 words
An apparatus according to claim 4, wherein said arcuate magnet is stationary.
Claim 7
Dependent Claim 13 words
An apparatus according to claim 2, wherein the member is a flexible belt.
Claim 8
Dependent Claim 31 words
An apparatus according to claim 6, further including means for wrapping the flexible about a portion of the exterior circumferential surface of said tubular member to form an extended development zone.
Claim 9
Dependent Claim 40 words
An apparatus according to claim 7, wherein said wrapping means wraps the flexible belt about the exterior circumferential surface of said tubular member in response to said moving means moving said magnet from the non-operative position to the operative position.
Claim 10
Dependent Claim 40 words
An apparatus according to claim 8, wherein said wrapping means spaces the flexible belt from the exterior circumferential surface of said tubular member in response to said moving means moving said magnet from the operative position to the non-operative position.
Claim 11
Dependent Claim 114 words
An electrophotographic printing machine adapted to have an electrostatic latent image recorded on a photoconductive member developed with developer material, wherein the improvement includes: means, for transporting the developer material into a development zone so as to develop the latent image recorded on the photoconductive member with developer material; a magnet operatively associated with said transporting means to attract developer material thereto in a non-operative position and to release developer material therefrom in an operative position; and means for moving said magnet between an operative position, wherein said magnet generates a weak magnetic field in the development zone, and a non-operative position, wherein said magnet generates a strong magnet field in the development zone.
Claim 12
Dependent Claim 114 words
An electrophotographic printing machine adapted to have an electrostatic latent image recorded on a photoconductive member developed with developer material, wherein the improvement includes: means, for transporting the developer material into a development zone so as to develop the latent image recorded on the photoconductive member with developer material; a magnet operatively associated with said transporting means to attract developer material thereto in a non-operative position and to release developer material therefrom in an operative position; and means for moving said magnet between an operative position, wherein said magnet generates a weak magnetic field in the development zone, and a non-operative position, wherein said magnet generates a strong magnet field in the development zone.
Claim 13
Dependent Claim 24 words
A printing machine according to claim 10, wherein said transporting means includes a tubular member having said magnet disposed interiorly thereof and spaced therefrom.
Claim 14
Dependent Claim 19 words
A printing machine according to claim 11, further including an arcuate magnet positioned disposed interiorly of said tubular member.
Claim 15
Dependent Claim 37 words
A printing machine according to claim 12, wherein said moving means translates said magnet between the non-operative position and the operative position with the non-operative position being adjacent the development zone and the operative position remote therefrom.
Claim 16
Dependent Claim 13 words
A printing machine according to claim 13, wherein said arcuate magnet is stationary.
Claim 17
Dependent Claim 15 words
A printing machine according to claim 11, wherein the photoconductive member is a flexible belt.
Claim 18
Dependent Claim 33 words
A printing machine according to claim 15, further including means for wrapping the flexible belt about a portion of the exterior circumferential surface of said tubular member to form an extended development zone.
Claim 19
Dependent Claim 41 words
A printing machine according to claim 16, wherein said wrapping means wraps the flexible belt about the exterior circumferential surface of said tubular member in response to said moving means moving said magnet from the non-operative position to the operative position.
Claim 20
Dependent Claim 41 words
A printing machine according to claim 17, wherein said wrapping means spaces the flexible belt from the exterior circumferential surface of said tubular member in response to said moving means moving said magnet from the operative position to the non-operative position.

References Cited (Backward Citations)

US4801966A Cited
JPS62127878A Cited
US4752802A Cited
US4771311A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-11-19 1994-05-21 1994-11-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-11-19 1998-05-21 1998-11-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-11-19 2002-05-21 2002-11-20 $7700.00 Window Closed / Lapsed

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