摘要 |
<p>In an electrostatographic copying system wherein an image on an initial image support is transferred to a copy sheet, particularly by a transfer corona generator assisted by an auxiliary transfer corona generator applying pre-transfer charges to the initial image support, opposing conductive rollers measure the conductivity of each copy sheet prior to transfer and through a control circuit vary the voltages applied to both the transfer corona generator and the auxiliary transfer corona generator means accordingly. A relay switching system is disclosed automatically selecting between AC and two levels of DC transfer voltages in response to four different copy sheet humidity conditions to optimize the image transfer.</p> |