COPYRIGHT © 1999 CANON INC. CANON imageRUNNER 600 REV.1 JAN. 2000 PRINTED IN U.S.A. 6-29CHAPTER 6 IMAGE FORMATION SYSTEMFigure 6-311 Trailing Edge of Paper3. Correcting the Output at the Trailing Edge of PaperWhen paper moves through the transfer charging assembly, the resistance abruptly drops assoon as the paper leaves the assembly, possibly causing discharge current momentarily and, ulti-mately, leading to white spots or distorted images. To prevent such a problem, the transfer currentlevel is corrected (reduced) when the trailing edge of paper passes.Feeding direction20 mmPaperThe output of the transfer current isvaried over a width of 20 mm alongthe trailing edge of paper.Low humidityNormal humidityHigh humiditySingle-sided copying+220+150Double-sided copyingTransfer current correction (μA)In a low humidity environment, paper tends to dryup collecting excess charges (high resistance); tocounter, the output is reduced.When making a double-sided print, paper will absorb fixingoil and tend to collect less charges (low resistance); sincethe discharge current along the trailing edge of paper willbe low, the output is not varied.COPIER>OPTION>BODY>TRSW-P-B(transfer current output correctioncontrol ON/OFF)Related Service Mode1: do not vary the transfer current level. (default; select iftransfer faults occur along the trailing edge)0: correct the transfer current level along the trailing edge ofpaper.Table 6-302
