JPS5776562A - Electrophotographic cpier - Google Patents

Electrophotographic cpier

Info

Publication number
JPS5776562A
JPS5776562A JP55152027A JP15202780A JPS5776562A JP S5776562 A JPS5776562 A JP S5776562A JP 55152027 A JP55152027 A JP 55152027A JP 15202780 A JP15202780 A JP 15202780A JP S5776562 A JPS5776562 A JP S5776562A
Authority
JP
Japan
Prior art keywords
value
photosensor
original
bias
cpu14
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.)
Pending
Application number
JP55152027A
Other languages
Japanese (ja)
Inventor
Yasuo Sawada
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.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
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 Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP55152027A priority Critical patent/JPS5776562A/en
Publication of JPS5776562A publication Critical patent/JPS5776562A/en
Pending 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)
  • Exposure Or Original Feeding In Electrophotography (AREA)
  • Control Or Security For Electrophotography (AREA)

Abstract

PURPOSE:To prevent not only a faulty working of a copier due to the dust on an original and other factors but the soil on the surface of a copy sheet, by detecting a part of an optical image which gives an exposure to a drum through a photosensor and then setting the bias value of development with the mean value of those higher than the reference value among the detection outputs of the above-mentioned photosensor. CONSTITUTION:An original dividing mirror 10 divides a part of an optical image of an original 1 that gives an exposure to a photosensitive drum 9, and a photosensor 11 receives the divided beams. In such constitution, the detection signal of the sensor 11 is supplied to a CPU14 via an amplifying circuit 12 and an A/D converter 13. The value less than the reference value B is cut at the CPU14 to calculate the mean value of the signals at the texture part, and this output controls the output of a bias power supply 17 via a D/A converter 15 and a bias potential control circuit 16. In such way, the low bias application is eliminated although an abnormal value like signal C is caused by the dust. Thus the soil can be prevented on the surface of a copy sheet.
JP55152027A 1980-10-31 1980-10-31 Electrophotographic cpier Pending JPS5776562A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP55152027A JPS5776562A (en) 1980-10-31 1980-10-31 Electrophotographic cpier

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP55152027A JPS5776562A (en) 1980-10-31 1980-10-31 Electrophotographic cpier

Publications (1)

Publication Number Publication Date
JPS5776562A true JPS5776562A (en) 1982-05-13

Family

ID=15531452

Family Applications (1)

Application Number Title Priority Date Filing Date
JP55152027A Pending JPS5776562A (en) 1980-10-31 1980-10-31 Electrophotographic cpier

Country Status (1)

Country Link
JP (1) JPS5776562A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6010269A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPS6010267A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPS6010268A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPS6035751A (en) * 1983-08-06 1985-02-23 Canon Inc Image control device
JPS6053965A (en) * 1983-09-05 1985-03-28 Canon Inc Device for controlling recording of image
JPS60239729A (en) * 1984-05-14 1985-11-28 Sharp Corp Automatic exposure adjusting device
US4607954A (en) * 1983-02-26 1986-08-26 Mita Kogyo Kabushiki Kaisha Automatic developing bias control device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5393835A (en) * 1977-01-28 1978-08-17 Ricoh Co Ltd Copy picture quality controller of electrostatic copying machine
JPS5446560A (en) * 1977-09-20 1979-04-12 Ricoh Co Ltd Automatic texture blot compensating device
JPS5461535A (en) * 1977-10-25 1979-05-17 Ricoh Co Ltd Image density control device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5393835A (en) * 1977-01-28 1978-08-17 Ricoh Co Ltd Copy picture quality controller of electrostatic copying machine
JPS5446560A (en) * 1977-09-20 1979-04-12 Ricoh Co Ltd Automatic texture blot compensating device
JPS5461535A (en) * 1977-10-25 1979-05-17 Ricoh Co Ltd Image density control device

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4607954A (en) * 1983-02-26 1986-08-26 Mita Kogyo Kabushiki Kaisha Automatic developing bias control device
JPS6010269A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPS6010267A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPS6010268A (en) * 1983-06-30 1985-01-19 Canon Inc Image processor
JPH0532748B2 (en) * 1983-06-30 1993-05-17 Canon Kk
JPH0555867B2 (en) * 1983-06-30 1993-08-18 Canon Kk
JPH0555868B2 (en) * 1983-06-30 1993-08-18 Canon Kk
JPS6035751A (en) * 1983-08-06 1985-02-23 Canon Inc Image control device
JPH0555872B2 (en) * 1983-08-06 1993-08-18 Canon Kk
JPS6053965A (en) * 1983-09-05 1985-03-28 Canon Inc Device for controlling recording of image
JPS60239729A (en) * 1984-05-14 1985-11-28 Sharp Corp Automatic exposure adjusting device
JPH0576019B2 (en) * 1984-05-14 1993-10-21 Sharp Kk

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