Biased charge roller with embedded electrodes with post-nip breakdown to enable improved charge uniformity

摘要

Electrodes are embedded in a biased charge roller of a xerographic device. The electrodes, which may run the length of the roller, are deposited on an insulating substrate. A semi-conductive conformable layer of a flexible elastomer covers the electrodes. The semi-conductive conformable layer limits current flow between electrodes and relaxes charge deposited on the roller surface. Stationary pre-nip and post-nip contacts apply the bias to the imbedded electrodes. The electrodes in the post nip region are biased to V_POST. The electrodes positioned in the pre-nip regions are either grounded or biased to V_PREV_POST. The electroded biased charge roller may generate air breakdown in the post nip region, resulting in highly uniform charging.