JPS56128961A - Copying machine - Google Patents

Copying machine

Info

Publication number
JPS56128961A
JPS56128961A JP3193280A JP3193280A JPS56128961A JP S56128961 A JPS56128961 A JP S56128961A JP 3193280 A JP3193280 A JP 3193280A JP 3193280 A JP3193280 A JP 3193280A JP S56128961 A JPS56128961 A JP S56128961A
Authority
JP
Japan
Prior art keywords
potential
voltage
photoreceptor drum
development roller
capacitor
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
JP3193280A
Other languages
Japanese (ja)
Inventor
Tadahiro Eda
Harumi Takahashi
Susumu Tatsumi
Tsutomu Imai
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 JP3193280A priority Critical patent/JPS56128961A/en
Publication of JPS56128961A publication Critical patent/JPS56128961A/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)
  • Holders For Sensitive Materials And Originals (AREA)
  • Developing For Electrophotography (AREA)
  • Control Or Security For Electrophotography (AREA)

Abstract

PURPOSE:To rationalize copying conditions of a copying machine having a device which detects a photoreceptor potential and then controls a developing electrode voltage by adding some voltage to the detected potential, by varying the added voltage according to the properties of an original. CONSTITUTION:Developing device 11 is composed of a magnetic brush developing device which uses development roller 11a, and detector 20 is installed opposing to photoreceptor drum 1 at a very small interval in front of development roller 11a to induce the potential that corresponds to the surface potential of photoreceptor drum 1. This potential is amplified by amplifier 21 and stored in capacitor 23 via switch 22. Switch 22 is closed only at the timing when the leading edge part of an electrostatic latent image on photoreceptor drum 1 passes by detector 20, and the potential of the background at the leading edge part is stored in capacitor 23. This potential is multiplied by a coefficient by arithmetic circuit 24 and an additional voltage is added to the output of the arithmetic circuit to obtain a bias potential, which is applied to development roller 11a via switch 25 during development. Thus, copying conditions are optimized.
JP3193280A 1980-03-13 1980-03-13 Copying machine Pending JPS56128961A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3193280A JPS56128961A (en) 1980-03-13 1980-03-13 Copying machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3193280A JPS56128961A (en) 1980-03-13 1980-03-13 Copying machine

Publications (1)

Publication Number Publication Date
JPS56128961A true JPS56128961A (en) 1981-10-08

Family

ID=12344737

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3193280A Pending JPS56128961A (en) 1980-03-13 1980-03-13 Copying machine

Country Status (1)

Country Link
JP (1) JPS56128961A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60263172A (en) * 1984-06-11 1985-12-26 Sharp Corp Image correcting method of copying machine
JPS61148460A (en) * 1984-12-21 1986-07-07 Fujitsu Ltd Driving control system of laser printer
JPH04121458A (en) * 1989-12-21 1992-04-22 Briggs & Stratton Corp Speed limiter for internal combustion engine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5398834A (en) * 1977-02-09 1978-08-29 Canon Inc Controller for electrostatic device
JPS53105230A (en) * 1977-02-25 1978-09-13 Ricoh Co Ltd Optimum maintaining method of electrophotographical duplication images

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5398834A (en) * 1977-02-09 1978-08-29 Canon Inc Controller for electrostatic device
JPS53105230A (en) * 1977-02-25 1978-09-13 Ricoh Co Ltd Optimum maintaining method of electrophotographical duplication images

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60263172A (en) * 1984-06-11 1985-12-26 Sharp Corp Image correcting method of copying machine
JPS61148460A (en) * 1984-12-21 1986-07-07 Fujitsu Ltd Driving control system of laser printer
JPH04121458A (en) * 1989-12-21 1992-04-22 Briggs & Stratton Corp Speed limiter for internal combustion engine

Similar Documents

Publication Publication Date Title
JPS5767969A (en) Transcription device for electrophotographic copier for copying plural sheets
JPS56110968A (en) Electrophotographic device
JPS5486347A (en) Development stabilizing system
JPS56128961A (en) Copying machine
JPS53110840A (en) Electrophotographic copier
JPS5784463A (en) Image former
JPS5393835A (en) Copy picture quality controller of electrostatic copying machine
JPS55127573A (en) Gain adjusting method of toner image detector in electrophotographic copier
JPS5785070A (en) Control device for copying density of electrophotographic copier
JPS57104159A (en) Toner density detecting method
JPS5497034A (en) Image quality controller for electrostatic copier
JPS55117163A (en) Image forming device
JPS5729061A (en) Detector for remaining amount of toner of electrophotographic copier
JPS5590965A (en) Electrophotographic copier
JPS554577A (en) Electrometer
JPS5488131A (en) Auto bias developing device
JPH0413708B2 (en)
JPS54130134A (en) Developing bias control unit
JPS5737356A (en) Retention type electrostatic recording apparatus
JPS578553A (en) Recording device
JPS6255141B2 (en)
JPS57181568A (en) Electrophotographic copying machine
JPS5794770A (en) Cleaning method of electrophotographic photoreceptor
JPS55151665A (en) Electrode cleaning device of copying machine
JPS55117156A (en) Copying control method