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US3757999A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic developability control system for electrostatic recording apparatus

Assignee: Xerox Corp
•
Filing: 1972-11-03
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Granted: 1973-09-11
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Expires: 1992-11-03
📄 Original PDF 🌐 Google Patents

Abstract

Abstract A developability control system for an electrostatic recording apparatuin which a sensor including two parallel spaced NESA apparatus in plates through which developer material flows are connected in a circuit wherein each is electrically charged alternately for equal periods of time. While each plate is charged, it is adapted to attract toner. A light source on one side of the two plates and a photocell on the other side ''''senses'''' the sum toner deposit on the two plates at all times thereby effecting a steady state control signal.

Inventors

  • 👤 J Maksymiak

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 06:29
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0855; Y; Y10; Y10S; Y10S222/00; Y10S222/01

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 159 words
An apparatus for maintaining the developability of developing material, including a sensing device having a pair of spaced apart surfaces each adapted to carry a toner attracting charge, means for producing an attracting charge first on one of the surfaces and then on the other surface for each of a series of sensing cycles, said attracting charge being capable of attracting from the material a quantity of toner related to a desired predetermined level of developability in the material, said surfaces being arranged to be applied to developing material therebetween and with movement relative thereto in order to permit said cyclic attraction of the toner upon said surfaces, means for detecting the toner attracted to each of said surfaces during a series of sensing cycles when carrying an attracting charge, as related to the level of developability in the material, and means for adding toner to the material when the level of developability has deviated from said predetermined level.
Claim 2
Independent Claim 159 words
An apparatus for maintaining the developability of developing material, including a sensing device having a pair of spaced apart surfaces each adapted to carry a toner attracting charge, means for producing an attracting charge first on one of the surfaces and then on the other surface for each of a series of sensing cycles, said attracting charge being capable of attracting from the material a quantity of toner related to a desired predetermined level of developability in the material, said surfaces being arranged to be applied to developing material therebetween and with movement relative thereto in order to permit said cyclic attraction of the toner upon said surfaces, means for detecting the toner attracted to each of said surfaces during a series of sensing cycles when carrying an attracting charge, as related to the level of developability in the material, and means for adding toner to the material when the level of developability has deviated from said predetermined level.
Claim 3
Dependent Claim 28 words
The apparatus of claim 1 wherein the level of developability of the material during said series of sensing cycles is related as to the rate of toner attraction.
Claim 4
Dependent Claim 22 words
The apparatus of claim 1 wherein the detecting means is adapted to produce a non-cyclic signal having a near straight line form.
Claim 5
Independent Claim 170 words
An apparatus for maintaining the developability of developing material, by including a sensing device having a pair of spaced apart surfaces each adapted to carry a toner attracting and a toner repelling charge, means for producing an attracting charge first on one of the surfaces and then on the other surface for each of a series of sensing cycles and for producing a repelling charge on that surface not having an attracting charge during each cycle, said attacting charge being capable of attracting from the material a quantity of toner related to a desired predetermined level of developability in the material, said surfaces being arranged to be applied to developing material therebetween with movement relative thereto in order to permit said cyclic attraction of the toner upon said surfaces, means for detecting the toner attracted to said surfaces during a series of sensing cycles as related to the level of developability, and means for adding toner to the material when the level of developability has deviated from said predetermined level.
Claim 6
Independent Claim 170 words
An apparatus for maintaining the developability of developing material, by including a sensing device having a pair of spaced apart surfaces each adapted to carry a toner attracting and a toner repelling charge, means for producing an attracting charge first on one of the surfaces and then on the other surface for each of a series of sensing cycles and for producing a repelling charge on that surface not having an attracting charge during each cycle, said attacting charge being capable of attracting from the material a quantity of toner related to a desired predetermined level of developability in the material, said surfaces being arranged to be applied to developing material therebetween with movement relative thereto in order to permit said cyclic attraction of the toner upon said surfaces, means for detecting the toner attracted to said surfaces during a series of sensing cycles as related to the level of developability, and means for adding toner to the material when the level of developability has deviated from said predetermined level.
Claim 7
Dependent Claim 28 words
The apparatus of claim 4 wherein the level of developability of the material during said series of sensing cycles is related as to the rate of toner attraction.
Claim 8
Dependent Claim 22 words
The apparatus of claim 4 wherein the detecting means is adapted to produce a non-cyclic signal having a near straight line form.
Claim 9
Dependent Claim 178 words
A toner dispensing control device for use in an electrostatic reproduction apparatus having a photosensitive plate and a developing system adapted to apply electrostatically charged toner from developing material to exposed electrostatic latent images on the plate thereby producing powdered toner images thereon including, sensing means arranged to be applied to developing material including a pair of spaced apart, transparent elements, means for cyclically producing an electrical charge on first one and then the other of the elements capable of attracting toner thereon, means for directing light rays through said elements and the toner attracted thereto, a light sensitive device arranged to receive some of the light rays projecting through said elements and to produce a steady state signal in accordance with the toner density of the attracted toner during repeated sensing cycles, means for comparing said signal with a predetermined signal that is indicative of optimum developability of the developing material, and dispensing means responsive to the deviation of said steady state signal from said predetermined signal for effecting the dispensing of toner into the developing system.
Claim 10
Dependent Claim 178 words
A toner dispensing control device for use in an electrostatic reproduction apparatus having a photosensitive plate and a developing system adapted to apply electrostatically charged toner from developing material to exposed electrostatic latent images on the plate thereby producing powdered toner images thereon including, sensing means arranged to be applied to developing material including a pair of spaced apart, transparent elements, means for cyclically producing an electrical charge on first one and then the other of the elements capable of attracting toner thereon, means for directing light rays through said elements and the toner attracted thereto, a light sensitive device arranged to receive some of the light rays projecting through said elements and to produce a steady state signal in accordance with the toner density of the attracted toner during repeated sensing cycles, means for comparing said signal with a predetermined signal that is indicative of optimum developability of the developing material, and dispensing means responsive to the deviation of said steady state signal from said predetermined signal for effecting the dispensing of toner into the developing system.

References Cited (Backward Citations)

US3094049A Cited
US3233781A Cited
US3376854A Cited
US3399652A Cited
US3430606A Cited
US3526338A Cited
US3682132A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-09-10 1977-03-12 1977-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-09-10 1981-03-12 1981-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-09-10 1985-03-12 1985-09-11 $7700.00 Window Closed / Lapsed

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