Sharp SF-7700 - Developer Unit

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[11] DEVELOPER UNIT
1. General description
An electrostaticlatent image is formed on the drum surface and
toneris appliedoverthe latentimageto changeitto a visibleimage.
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Toner is chargedbyfrictionwiththe carrier(devehper bythe stirring
rollerwithinthe developer unit. The toner is charg~ positiveand
the carrier negative.
The latent image area not exposed by light is charged negative.
The toners positivepotentialis attractedto that area.
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A bias potentialof –~OVDC is applied to the MG rollerfrom the
bias PWB during.the developingprocess.
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2. Adjustments
(1) Mainpoleadjustment
The bouble describedneti may occur if the DV doctorblade was
improperlyadjusted.
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. Lack of copy density
●Toner dusting
@ As illustratedin the figurebelow,stretchone end of a paper ~ip
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and,tie the other end with,astring.
NOTE: Clear the developer away fromthe MG rollerarea.
Paperdip
\
String
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@ Hold the stringand bringthe paper clipclose to theMG roller:
@ Mark the surfau of the MG roller sleeve where the clip made
contactwith the MG roller.
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SF-7700
SF–77=
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Measure the disfa~ between the MS* and point (A) on the
DVdoctorblade.Makssura ifthedistancaiswi~in~.7f0.2mm.
If not,Imsen the K rolleradjueti~.~ate screwand move ifto
adjust.Then,repeatsteps@to@ again,tochecktheadju~ent.
Mak
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DV&r Wade
@ Tightenthe MG rolleradjustingplate screw.
(2) DV dWor bladeto MG rollergap adjustment
This adjustmentrnuatbe done afterthecom~etion of the man pole
adjustment.Revep wcs is not permitted.
% troubledescrfbednem may occur if the DV doctor.Made was
impro@y adjusted.
●Lack of WW density
●Backgroundon the cow
●Toner dusting
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@ LoosentwoDV doctortide screwsIocatd’wifhin the DV doctor
blade.
@ Insertone each of 1.7mm Wer gatigaa betweenthe MG roller
and the DV doctorblada,each one IODmmawayfromthecenter
of the deve~r unit(see figure
bebw).
@
Tightenthe DV*rMada~ewwhile pressingthe DVdoctor
blade in the arrowdir-n.
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