| 摘要 |
PURPOSE:To contrive continuation of good corona discharge even in change of humidity and enable stable charge, transfer, separation and destaticization by controlling the applied voltage to a corona discharger responding to outputs of a humidity sensor provided near a photosensitive body. CONSTITUTION:A voltage higher than the corona starting voltage corresponding to absolute humidity is applied by a power source 5 to a discharge electrode wire 1. Consequently, corona discharge is caused between the discharge electrode wire 1 and paired electrodes 11, and charge is formed on a charged body 10, i.e. a photosensitive body, and the potential of the photosensitive body becomes a certain charge potential. A voltage of the polarity equal to the discharge electrode wire 1, several hundreds volt, is applied from a power source 3. In the case where absolute humidity near the photosensitive body becomes high, the corona starting voltage also becomes higher. However, resistance of a humidity sensor 8 also increases, and the voltage applied to the discharge electrode wire 1 becomes higher, and corona discharge is maintained. Even when absolute humidity becomes low, the voltage applied to the discharge electrode wire 1 also becomes low, and discharge becomes whole path destruction, and generation of spark discharge can be prevented. |
