JPS56151957A - Developing voltage generator of copying machine - Google Patents

Developing voltage generator of copying machine

Info

Publication number
JPS56151957A
JPS56151957A JP5517780A JP5517780A JPS56151957A JP S56151957 A JPS56151957 A JP S56151957A JP 5517780 A JP5517780 A JP 5517780A JP 5517780 A JP5517780 A JP 5517780A JP S56151957 A JPS56151957 A JP S56151957A
Authority
JP
Japan
Prior art keywords
voltage
developing
developing voltage
vref2
vref1
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
JP5517780A
Other languages
Japanese (ja)
Inventor
Hiromitsu Yagi
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 JP5517780A priority Critical patent/JPS56151957A/en
Publication of JPS56151957A publication Critical patent/JPS56151957A/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

Abstract

PURPOSE:To easily set the optimum developing voltage corresponding to the state of original images by dividing the source voltage by resistance circuits and selectively applying the divided voltages to a developing electrode by means of control switches and a developing voltage selecting part. CONSTITUTION:This is constituted of a voltage dividing resistance circuit consisting of resistances R1-R4, control switches SW1-SW3, and a developing voltage selecting part 2. For example, at the time of automatic setting, the peak value of the image signal read with a photosensor 4 is outputted as a control signal Vc via a peak holding circut 5, and is compared respectively with the reference voltages (Vref1>Vref2>Vref3) having beforehand been set in 3 stages, whereby the density level of the original images is detected. This turns out that the maximum voltage V1 when Vc>=Vref1, the intermediate developing voltage V2 when Vref1>Vc>Vref2 and further the manimum voltage V3 when Vref2>Vc>=Vref3 are respectively applied to a developing electrode. With such constitution, the optimum developing voltage corresponding to the state of the original images is easily set.
JP5517780A 1980-04-25 1980-04-25 Developing voltage generator of copying machine Pending JPS56151957A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5517780A JPS56151957A (en) 1980-04-25 1980-04-25 Developing voltage generator of copying machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5517780A JPS56151957A (en) 1980-04-25 1980-04-25 Developing voltage generator of copying machine

Publications (1)

Publication Number Publication Date
JPS56151957A true JPS56151957A (en) 1981-11-25

Family

ID=12991436

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5517780A Pending JPS56151957A (en) 1980-04-25 1980-04-25 Developing voltage generator of copying machine

Country Status (1)

Country Link
JP (1) JPS56151957A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6050558A (en) * 1983-08-30 1985-03-20 Matsushita Electric Ind Co Ltd Electrophotographic copying machine
JPS6050557A (en) * 1983-08-30 1985-03-20 Matsushita Electric Ind Co Ltd Electrophotographic copying machine

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5436725A (en) * 1977-08-26 1979-03-17 Ricoh Co Ltd Zerographic copying method

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5436725A (en) * 1977-08-26 1979-03-17 Ricoh Co Ltd Zerographic copying method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6050558A (en) * 1983-08-30 1985-03-20 Matsushita Electric Ind Co Ltd Electrophotographic copying machine
JPS6050557A (en) * 1983-08-30 1985-03-20 Matsushita Electric Ind Co Ltd Electrophotographic copying machine

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