Patent ID: 6807389
Filing Date: 2004-10-19
Classification: G03G

Abstract:
An apparatus for applying an electrical charge to a member to be charged, comprising:a. a charge roll member situated proximately to a surface of the member to be charged; b. a power supply for supplying an oscillating voltage signal to the charge roll member; c. a device, interposed between the power supply and the charge roll member, for removing a selected polarity component of the oscillating voltage signal, thereby supplying a voltage signal to the charge roll member comprised of a rectified waveform with a DC bias offset; wherein a first and second Paschen threshold voltage exist between the charge roll member and a member to be charged; wherein a portion of the voltage signal exceeds the first Paschen threshold voltage, thereby inducing a corona of the same polarity as the rectified waveform; and wherein a portion of the voltage signal exceeds the second Paschen threshold voltage, thereby inducing a corona of the opposite polarity of the rectified waveform.