JPS5488131A - Auto bias developing device - Google Patents

Auto bias developing device

Info

Publication number
JPS5488131A
JPS5488131A JP15682277A JP15682277A JPS5488131A JP S5488131 A JPS5488131 A JP S5488131A JP 15682277 A JP15682277 A JP 15682277A JP 15682277 A JP15682277 A JP 15682277A JP S5488131 A JPS5488131 A JP S5488131A
Authority
JP
Japan
Prior art keywords
developing device
potential
magnet brush
photoreceptor
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
JP15682277A
Other languages
Japanese (ja)
Inventor
Tadahiro Eda
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 JP15682277A priority Critical patent/JPS5488131A/en
Publication of JPS5488131A publication Critical patent/JPS5488131A/en
Pending legal-status Critical Current

Links

Landscapes

  • Developing For Electrophotography (AREA)
  • Control Or Security For Electrophotography (AREA)

Abstract

PURPOSE: To provide the developing device of a simple constitution in which a detector is not required by controlling the developing bias with the output of detection which corresponds to the electric potential of a material to be developed resulting from the exciation at a magnet brush developing device.
CONSTITUTION: Electric potential in proportion to the surface potential of photoreceptor 11 is excited at magnet brush developing device 12. The excited voltage corresponding to the background of electrostatic latent image of the photoreceptor 11 is detected by the voltage follower A1 of high input resistance and memorized by the charging of capacitor C1 via image timing switch S1 which closes when the forward tip of the electrostatic latent image reaches the device 12. Therefore the bias voltage of the magnet brush developing device 13 is automatically controlled with the added potential resulting from the multiplication of charged potential of capacitor C1 by the predetermined coefficient due to arithmetic circuit A2.
COPYRIGHT: (C)1979,JPO&Japio
JP15682277A 1977-12-26 1977-12-26 Auto bias developing device Pending JPS5488131A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15682277A JPS5488131A (en) 1977-12-26 1977-12-26 Auto bias developing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15682277A JPS5488131A (en) 1977-12-26 1977-12-26 Auto bias developing device

Publications (1)

Publication Number Publication Date
JPS5488131A true JPS5488131A (en) 1979-07-13

Family

ID=15636094

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15682277A Pending JPS5488131A (en) 1977-12-26 1977-12-26 Auto bias developing device

Country Status (1)

Country Link
JP (1) JPS5488131A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61289368A (en) * 1985-06-13 1986-12-19 ゼロツクス　コ−ポレ−シヨン Electrophotographic printing machine
JPS6290570A (en) * 1985-05-02 1987-04-25 ゼロツクス　コ−ポレ−シヨン Measuring device for surface potential

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6290570A (en) * 1985-05-02 1987-04-25 ゼロツクス　コ−ポレ−シヨン Measuring device for surface potential
JPS61289368A (en) * 1985-06-13 1986-12-19 ゼロツクス　コ−ポレ−シヨン Electrophotographic printing machine

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