GB1352863A - Bias control for electrostatic image development - Google Patents

Bias control for electrostatic image development

Info

Publication number
GB1352863A
GB1352863A GB1265771*[A GB1265771A GB1352863A GB 1352863 A GB1352863 A GB 1352863A GB 1265771 A GB1265771 A GB 1265771A GB 1352863 A GB1352863 A GB 1352863A
Authority
GB
United Kingdom
Prior art keywords
image
capacitor
input
electro
amplified
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB1265771*[A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eastman Kodak Co
Original Assignee
Eastman Kodak Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Publication of GB1352863A publication Critical patent/GB1352863A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/065—Arrangements for controlling the potential of the developing electrode

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Developing For Electrophotography (AREA)

Abstract

1352863 Electro-photographic developing process EASTMAN KODAK CO 3 May 1971 [1 May 1970] 12657/71 Heading G2H An electro-photographic developing process comprises measuring the charge levels of the background areas of an electrostatic latent image and controlling the bias applied to a development electrode accordingly. As shown, as an image bearing web 10 is fed past a probe 17, an electrometer 19 provides an input at 45 proportional to the charge level. The input is amplified at 21 and, if less than a predetermined value, causes a capacitor 30 to discharge through a resistor 47 and diode 46 to a voltage corresponding to the input. Contact 25A is kept open by a photo-cell detector 24 while the whole of the image passes probe 17, so that the final charge on capacitor 30 corresponds to the minimum charge level of the image. When the image passes another photo-cell detector 26, a contact 27A is closed and the voltage on capacitor 30, amplified at 22 and 23, controls a voltage supply 18 which biases magnetic brushes 14 at an image developing station 13.
GB1265771*[A 1970-05-01 1971-05-03 Bias control for electrostatic image development Expired GB1352863A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US3357170A 1970-05-01 1970-05-01

Publications (1)

Publication Number Publication Date
GB1352863A true GB1352863A (en) 1974-05-15

Family

ID=21871180

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1265771*[A Expired GB1352863A (en) 1970-05-01 1971-05-03 Bias control for electrostatic image development

Country Status (5)

Country Link
US (1) US3654893A (en)
CA (1) CA925690A (en)
DE (1) DE2121788A1 (en)
FR (1) FR2090922A5 (en)
GB (1) GB1352863A (en)

Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3805739A (en) * 1971-06-11 1974-04-23 Xerox Corp Controlling multiple voltage levels for electrostatic printing
US3719165A (en) * 1971-09-03 1973-03-06 Eastman Kodak Co Tuner concentration control apparatus
US3850662A (en) * 1971-09-10 1974-11-26 Kalle Ag Electrophotographic developing process and apparatus
US3821938A (en) * 1971-12-17 1974-07-02 Ibm Toner usage sensing system
US3823688A (en) * 1972-01-26 1974-07-16 Xerox Corp Magnetic brush assembly
US3922380A (en) * 1973-06-18 1975-11-25 Eastman Kodak Co Auto bias control method
US3877413A (en) * 1973-06-18 1975-04-15 Eastman Kodak Co Auto bias control apparatus
US3889637A (en) * 1973-06-28 1975-06-17 Xerox Corp Self-biased development electrode and reproducing machine employing same
US3893419A (en) * 1973-12-26 1975-07-08 Xerox Corp Background reduction technique
US3918395A (en) * 1974-03-04 1975-11-11 Eastman Kodak Co Continuous bias control for electrographic development apparatus
US3891316A (en) * 1974-03-18 1975-06-24 Xerox Corp Multi-process control system for an electrophotographic printing machine
USRE31964E (en) * 1974-06-17 1985-08-06 Savin Corporation Automatic development electrode bias control system
US3892481A (en) * 1974-06-17 1975-07-01 Savin Business Machines Corp Automatic development electrode bias control system
JPS5810746B2 (en) * 1974-12-24 1983-02-26 株式会社リコー Denshisha Shingen Zosouchi
US3981268A (en) * 1975-06-11 1976-09-21 Fuji Xerox Co., Ltd. Device for controlling electric potential applied to developing electrode in an electrophotographic duplicator
US4021112A (en) * 1975-06-23 1977-05-03 Xerox Corporation Photoreceptor dark current leakage detecting apparatus for xerographic machines
JPS5243439A (en) * 1975-10-03 1977-04-05 Ricoh Co Ltd Generator for the bias voltage for the electrophotographic copying machine
JPS6044653B2 (en) * 1976-05-17 1985-10-04 株式会社リコー Developing bias automatic control method and device
US4105321A (en) * 1976-10-27 1978-08-08 Xerox Corporation Illuminated charge control system for xerographic machines
US4248519A (en) * 1976-10-27 1981-02-03 Xerox Corporation Charge control system for xerographic machines
DE2655158C2 (en) * 1976-12-06 1986-04-03 Hoechst Ag, 6230 Frankfurt Method and apparatus for developing an electrostatic latent image
US4083326A (en) * 1977-02-28 1978-04-11 Eastman Kodak Company Single component developer applicator apparatus
JPS53110840A (en) * 1977-03-09 1978-09-27 Toshiba Corp Electrophotographic copier
US4102305A (en) * 1977-07-01 1978-07-25 Xerox Corporation Development system with electrical field generating means
JPS5497039A (en) * 1978-01-17 1979-07-31 Konishiroku Photo Ind Co Ltd Bias voltage change-over circuit for image density control of copier
US4279942A (en) * 1980-03-03 1981-07-21 Eastman Kodak Company Magnetic field adjustment for magnetic brushes
US4442790A (en) * 1982-09-29 1984-04-17 Eastman Kodak Company Magnetic brush development apparatus
US4496644A (en) * 1983-02-28 1985-01-29 Eastman Kodak Company Electric field adjustment for magnetic brushes
US4600294A (en) * 1983-04-01 1986-07-15 Canon Kabushiki Kaisha Image forming apparatus with detector and control
US4571055A (en) * 1983-12-17 1986-02-18 Sharp Kabushiki Kaisha Transport item detecting arrangement
US5081492A (en) * 1990-12-12 1992-01-14 Xerox Corporation Exposure control system

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2956487A (en) * 1955-03-23 1960-10-18 Rca Corp Electrostatic printing
US3013203A (en) * 1958-07-01 1961-12-12 Xerox Corp Xerographic electrometer apparatus
US3058444A (en) * 1959-03-13 1962-10-16 American Photocopy Equip Co Apparatus for developing electrostatic image on electrographic sheet
US3406334A (en) * 1964-07-27 1968-10-15 Nuclear Corp Of America Apparatus for testing electrostatic copy material
US3553595A (en) * 1967-07-28 1971-01-05 Honeywell Inc Control apparatus

Also Published As

Publication number Publication date
CA925690A (en) 1973-05-08
DE2121788A1 (en) 1971-11-18
US3654893A (en) 1972-04-11
FR2090922A5 (en) 1972-01-14

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee