JPS5660462A - Exposure light quantity adjusting device of slit exposure type variable magnification copying machine - Google Patents

Exposure light quantity adjusting device of slit exposure type variable magnification copying machine

Info

Publication number
JPS5660462A
JPS5660462A JP13683979A JP13683979A JPS5660462A JP S5660462 A JPS5660462 A JP S5660462A JP 13683979 A JP13683979 A JP 13683979A JP 13683979 A JP13683979 A JP 13683979A JP S5660462 A JPS5660462 A JP S5660462A
Authority
JP
Japan
Prior art keywords
photosensitive material
discharging equipment
corona discharging
part potential
light quantity
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.)
Granted
Application number
JP13683979A
Other languages
Japanese (ja)
Other versions
JPH0219954B2 (en
Inventor
Hiroshi Ogawa
Shigehiro Komori
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP13683979A priority Critical patent/JPS5660462A/en
Priority to US06/141,922 priority patent/US4411514A/en
Priority to DE19803015820 priority patent/DE3015820A1/en
Publication of JPS5660462A publication Critical patent/JPS5660462A/en
Publication of JPH0219954B2 publication Critical patent/JPH0219954B2/ja
Granted legal-status Critical Current

Links

Landscapes

  • Exposure Or Original Feeding In Electrophotography (AREA)
  • Variable Magnification In Projection-Type Copying Machines (AREA)
  • Control Or Security For Electrophotography (AREA)

Abstract

PURPOSE:To make it possible to adjust the exposure light quantity to the photosensitive material stably and accurately, by changing the electric field intensity between the corona discharging equipment and the photosensitive material to an intensity corresponding to the selected circumferential speed of the photosensitive material to control corona discharge given to the photosensitive material. CONSTITUTION:The reference current is flowed to corona discharging equipment 21 for primary charging and corona discharging equipment 22 for electricity removal while photosensitive material 10 is rotated in a circumferential speed corresponding to the selected copying magnification, and the bright part potential and the dark part potential on the surface of the photosensitive material are measured alternately by sensor 29. These signals of the bright part potential and the dark part potential are input to operation control circuit 32 through amplifying circuit 31. The signal set previously of target potential constant signal generating means 33 and the detection signal of sensor 29 are compared with each other, and their difference is calculated, and the calculated correction current according to the correction expression set previously is added to the reference current. This added current is applied to corona discharging equipment 21 for primary charging and corona discharging equipment 22 for electricity removal through power sources 34 and 35.
JP13683979A 1979-04-24 1979-10-23 Exposure light quantity adjusting device of slit exposure type variable magnification copying machine Granted JPS5660462A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP13683979A JPS5660462A (en) 1979-10-23 1979-10-23 Exposure light quantity adjusting device of slit exposure type variable magnification copying machine
US06/141,922 US4411514A (en) 1979-04-24 1980-04-21 Variable magnification electrophotographic copying apparatus
DE19803015820 DE3015820A1 (en) 1979-04-24 1980-04-24 Variable magnification photocopier with constant scanning speed - has variable speed photo-sensitive layer and corrected corona charging rate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13683979A JPS5660462A (en) 1979-10-23 1979-10-23 Exposure light quantity adjusting device of slit exposure type variable magnification copying machine

Publications (2)

Publication Number Publication Date
JPS5660462A true JPS5660462A (en) 1981-05-25
JPH0219954B2 JPH0219954B2 (en) 1990-05-07

Family

ID=15184701

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13683979A Granted JPS5660462A (en) 1979-04-24 1979-10-23 Exposure light quantity adjusting device of slit exposure type variable magnification copying machine

Country Status (1)

Country Link
JP (1) JPS5660462A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58160967A (en) * 1982-03-19 1983-09-24 Matsushita Electric Ind Co Ltd Variable power copying machine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4898842A (en) * 1972-03-29 1973-12-14
JPS5010124A (en) * 1973-05-24 1975-02-01

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4898842A (en) * 1972-03-29 1973-12-14
JPS5010124A (en) * 1973-05-24 1975-02-01

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58160967A (en) * 1982-03-19 1983-09-24 Matsushita Electric Ind Co Ltd Variable power copying machine

Also Published As

Publication number Publication date
JPH0219954B2 (en) 1990-05-07

Similar Documents

Publication Publication Date Title
JPS55157756A (en) Surface potential control unit
JPS5518667A (en) Stabilization method of image density
CA1079129A (en) Process and apparatus for developing an electrostatic latent image
US4390265A (en) Image forming apparatus
JPS55153970A (en) Developer replenishing time detector
JPS5660462A (en) Exposure light quantity adjusting device of slit exposure type variable magnification copying machine
JPS5784463A (en) Image former
JPS5484738A (en) Developing device for variable magnification copier
ES8607577A1 (en) Method and device for getting a predetermined value of potential by the illumination of electrostatically charged photoconductive layers.
JPS55142368A (en) Variable magnification copying machine
JPS5473055A (en) Charge quantity controller in electrophotographic copier
JPS56161555A (en) Controller of electrophotographic copying machine
JPS5688142A (en) Image density control device
JPS5664367A (en) Transfer device
JPS5529857A (en) Electrostatic recorder
JPS5589856A (en) Electrophotographic method
JPS5786842A (en) Adjustment device for density irregularity of electrophotographic copying machine
JPS5677850A (en) Method of controlling surface potential of photoreceptor of electrophotographic copier
SU900470A1 (en) Static charge neutralizer
JPS59169A (en) Device for controlling surface potential
JPS5677852A (en) Variable magnification controllable copying apparatus
JPS5742056A (en) Electrostatic printing control method
JPS57173841A (en) Electrostatic recorder
JPS5647064A (en) Discharge quantity controlling method of discharger for electrophotography or electrostatic recording
JPS5511257A (en) Corona discharger-charger