US4267797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Development system
Assignee: Xerox Corp
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Filing: 1979-04-27
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Granted: 1981-05-19
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Expires: 1999-04-27
Abstract
Abstract An apparatus which develops a latent image by advancing a conductive developer composition comprising marking particles into contact therewith. The apparatus interacts with the developer composition causing the developer composition to have higher and lower regions of conductivity. In the regions of higher conductivity, development of the solid areas within the latent image is optimized. Development of lines within the latent image is optimized in the regions of lower conductivity.
Inventors
- 👤 Raymond W. Huggins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:43
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
116 words
An apparatus for developing a latent image, including: first magnetic means for advancing a conductive developer composition comprising marking particles into contact with the latent image, said first means interacting with the developer composition causing the developer composition to have a first conductivity so as to optimize development of solid areas within the latent image with the marking particles; and second magnetic means, spaced from said first means, for advancing the developer composition into contact with the latent image, said second means interacting with the developer composition causing the developer composition to have a second conductivity lower than the first conductivity so as to optimize development of lines within the latent image with the marking particles.
Claim 2
Independent Claim
116 words
An apparatus for developing a latent image, including: first magnetic means for advancing a conductive developer composition comprising marking particles into contact with the latent image, said first means interacting with the developer composition causing the developer composition to have a first conductivity so as to optimize development of solid areas within the latent image with the marking particles; and second magnetic means, spaced from said first means, for advancing the developer composition into contact with the latent image, said second means interacting with the developer composition causing the developer composition to have a second conductivity lower than the first conductivity so as to optimize development of lines within the latent image with the marking particles.
Claim 3
Dependent Claim
46 words
An apparatus as recited in claim 1, wherein said first means includes: means for forming a first magnetic field; and means for electrically biasing said first forming means to produce an electrical field with the magnetic field vector being substantially normal to the electrical field vector.
Claim 4
Dependent Claim
61 words
An apparatus as recited in claim 2, wherein said first forming means includes: a first elongated magnetic member oriented so as to position remotely the magnetic poles from the region opposed to the latent image in the development zone; and a first non-magnetic tubular member journaled for rotary movement, said first tubular member having said first elongated member disposed interiorly thereof.
Claim 5
Dependent Claim
46 words
An apparatus as recited in claim 3, wherein said second means includes: means for forming a second magnetic field; and means for electrically biasing said second forming means to produce an electrical field with the magnetic field vector being substantially parallel to the electrical field vector.
Claim 6
Dependent Claim
57 words
An apparatus as recited in claim 4, wherein said second forming means includes: a second elongated magnetic member oriented so as to position a magnetic pole opposed to the latent image in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 7
Dependent Claim
45 words
An apparatus as recited in claim 5, with said first tubular member being spaced a first distance from the latent image and said second tubular member being spaced a second distance from the latent image with the first distance being less than the second distance.
Claim 8
Dependent Claim
55 words
An apparatus as recited in claim 3, wherein said second means includes: a second elongated magnetic member oriented to position a weak magnetic pole opposed to the latent image in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 9
Dependent Claim
45 words
An apparatus as recited in claim 7, with said first tubular member being spaced a first distance from the latent image and said second tubular member being spaced a second distance from the latent image with the first distance being less than the second distance.
Claim 10
Dependent Claim
77 words
An apparatus as recited in claim 3, wherein said second means includes: a second elongated magnetic member oriented so as to position remotely the magnetic poles from the region opposed to the latent image in the development zone with said second elongated magnetic member generating a weaker magnetic field than said first elongated magnetic member; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 11
Dependent Claim
45 words
An apparatus as recited in claim 9, with said first tubular member being spaced a first distance from the latent image and said second tubular member being spaced a second distance from the latent image with the first distance being less than the second distance.
Claim 12
Dependent Claim
44 words
An apparatus as recited in claim 1, wherein said first means includes: means for forming a magnetic field; and means for electrically biasing said forming means to produce an electrical field with the magnetic field vector being substantially parallel to the electrical field vector.
Claim 13
Dependent Claim
56 words
An apparatus as recited in claim 11, wherein said forming means includes: a first elongated magnetic member oriented so as to position a magnetic pole opposed to the latent image in the development zone; and a first non-magnetic tubular member journaled for rotary movement, said first tubular member having said first magnetic member disposed interiorly thereof.
Claim 14
Dependent Claim
55 words
An apparatus as recited in claim 12, wherein said second means includes: a second elongated magnetic member oriented to position a weak magnetic pole opposed to the latent image in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 15
Dependent Claim
45 words
An apparatus as recited in claim 13, with said first tubular member being spaced a first distance from the latent image and said second tubular member being spaced a second distance from the latent image with the first distance being less than the second distance.
Claim 16
Dependent Claim
70 words
An apparatus as recited in claim 12, wherein said second means includes: a second elongated magnetic member oriented so as to position a magnetic pole opposed to the latent image in the development zone with said second magnetic member generating a weaker magnetic field than said first magnetic member; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said magnetic member disposed interiorly thereof.
Claim 17
Dependent Claim
45 words
An apparatus as recited in claim 15, with said first tubular member being spaced a first distance from the latent image and said second tubular member being spaced a second distance from the latent image with the first distance being less than the second distance.
Claim 18
Dependent Claim
139 words
An electrophotographic printing machine of the type having an electrostatic latent image recorded on a photoconductive member, wherein the improvement includes: first magnetic means for advancing a conductive developer composition comprising toner particles into contact with the latent image recorded on the photoconductive member, said first means interacting with the developer composition causing the developer composition to have a first conductivity so as to optimize development of solid areas within the latent image with the toner particles; and second magnetic means, spaced from said first means, for advancing the developer composition into contact with the latent image recorded on the photoconductive member, said second means interacting with the developer composition causing the developer composition to have a second conductivity lower than the first conductivity so as to optimize development of lines within the latent image with the toner particles.
Claim 19
Dependent Claim
139 words
An electrophotographic printing machine of the type having an electrostatic latent image recorded on a photoconductive member, wherein the improvement includes: first magnetic means for advancing a conductive developer composition comprising toner particles into contact with the latent image recorded on the photoconductive member, said first means interacting with the developer composition causing the developer composition to have a first conductivity so as to optimize development of solid areas within the latent image with the toner particles; and second magnetic means, spaced from said first means, for advancing the developer composition into contact with the latent image recorded on the photoconductive member, said second means interacting with the developer composition causing the developer composition to have a second conductivity lower than the first conductivity so as to optimize development of lines within the latent image with the toner particles.
Claim 20
Dependent Claim
46 words
A printing machine as recited in claim 17, wherein said first means includes: means for forming a first magnetic field; and means for electrically biasing said forming means to produce an electrical field with the magnetic field vector being substantially normal to the electrical field vector.
Claim 21
Dependent Claim
62 words
A printing machine as recited in claim 18, wherein said first forming means includes: a first elongated magnetic member oriented so as to position remotely the magnetic poles from the region opposed to the photoconductive member in the development zone; and a first non-magnetic tubular member journaled for rotary movement, said first tubular member having said first elongated member disposed interiorly thereof.
Claim 22
Dependent Claim
48 words
A printing machine as recited in claims 18 or 19, wherein said second means includes: means for forming a second magnitude field; and means for electrically biasing said forming means to produce an electrical field with the magnetic field vector being substantially parallel to the electrical field vector.
Claim 23
Dependent Claim
58 words
A printing machine as recited in claim 20, wherein said second forming means includes: a second elongated magnetic member oriented so as to position a magnetic pole opposed to the photoconductive member in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 24
Dependent Claim
46 words
A printing machine as recited in claim 21, with said first tubular member being spaced a first distance from the photoconductive member and said second tubular member being spaced a second distance from the photoconductive member with the first distance being less than the second distance.
Claim 25
Dependent Claim
56 words
A printing machine as recited in claim 19, wherein said second means includes: a second elongated magnetic member oriented to position a weak magnetic pole opposed to the photoconductive member in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 26
Dependent Claim
46 words
A printing machine as recited in claim 23, with said first tubular member being spaced a first distance from the photoconductive member and said second tubular member being spaced a second distance from the photoconductive member with the first distance being less than the second distance.
Claim 27
Dependent Claim
77 words
A printing machine as recited in claim 19, wherein said second means includes: a second elongated magnetic member oriented so as to position remotely the magnetic poles from the region opposed to the latent image in the development zone with said second elongated magnetic member generating a weaker magnetic field than said first elongated member; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 28
Dependent Claim
45 words
A printing machine as recited in claim 25, with said first tubular member being spaced a first distance from the photoconductive member and said second tubular member spaced a second distance from the photoconductive member with the first distance being less than the second distance.
Claim 29
Dependent Claim
46 words
A printing machine as recited in claim 17, wherein said first means includes: means for forming a first magnetic field; and means for electrically biasing said forming means to produce an electrical field with the magnetic field vector being substantially parallel to the electrical field vector.
Claim 30
Dependent Claim
57 words
A printing machine as recited in claim 27, wherein said forming means includes: a first elongated magnetic member oriented so as to position a magnetic pole opposed to the photoconductive member in the development zone; and a first non-magnetic tubular member journaled for rotary movement, said first tubular member having said first magnetic member disposed interiorly thereof.
Claim 31
Dependent Claim
56 words
A printing machine as recited in claim 28, wherein said second means includes: a second elongated magnetic member oriented to position a weak magnetic pole opposed to the photoconductive member in the development zone; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said second magnetic member disposed interiorly thereof.
Claim 32
Dependent Claim
44 words
A printing machine in claim 29, with said first tubular member being spaced a first distance from the photoconductive member and said second tubular member being spaced a second distance from the photoconductive member with the first distance being less than the second distance.
Claim 33
Dependent Claim
71 words
A printing machine as recited in claim 28, wherein said second means includes: a second elongated magnetic member oriented so as to position a magnetic pole opposed to the photoconductive member in the development zone with said second magnetic member generating a weaker magnetic field than said first magnetic member; and a second non-magnetic tubular member journaled for rotary movement, said second tubular member having said magnetic member disposed interiorly thereof.
Claim 34
Dependent Claim
46 words
A printing machine as recited in claim 31, with said first tubular member being spaced a first distance from the photoconductive member and said second tubular member being spaced a second distance from the photoconductive member with the first distance being less than the second distance.
References Cited (Backward Citations)
US3543720A
Cited
US3664857A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-18 | 1984-11-17 | 1985-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-18 | 1988-11-17 | 1989-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-18 | 1992-11-17 | 1993-05-19 | $7700.00 | Window Closed / Lapsed |