Sharp AL-1000 Service Manual

Also see for AL-1000 Series: Operation manual Operation manual Operation manual Operation manual

Contents

Start1) Because the grid potential is at a low level, the drum poten-tial is at about –400V. (Carrier may not be attracted thoughthe carrier is pulled towards the drum by the electrostaticforce of –400V.2) Developing bias ( –400V) is applied when the photoconduc-tor potential is switched from LOW to HIGH.3) Once developing bias (–400V) is applied and the photo con-ductor potential rises to HIGH, toner will not be attracted tothe drum.StopThe reverse sequence takes place.Retaining developing bias at an abnormal occurrenceFunctionThe developing bias will be lost if the power supply wasremoved during print process. In this event, the drum potentialslightly abates and the carrier makes deposits on the drum be-cause of strong static power. To prevent this, the machine in-corporates a function to retain the developing bias for a certainperiod and decrease the voltage gradually against possiblepower loss.Basic functionNormally, the developing bias voltage is retained for a certaintime before the drum comes to a complete stop if the machineshould stop before completing the normal print cycle. Thedeveloping bias can be added before resuming the operationafter an abnormal interruption. Therfore, carrier will not make adeposit on the drum surface.AL-1000/10106-4