| 摘要 |
<p>SELF-HEALING ELECTRODE FOR UNIFORM NEGATIVE CORONA The present invention relates to electrodes used for charging electrophotographic image surfaces in copying machines. More particularly, the disclosure is directed to the negative corona discharge electrodes which produce a negative charge that is applied to the photoconductive surface exposed to the corona discharge. In the present invention, the electrode structure includes a combination of a wire of valve metal with a high resistivity coating spread uniformly over the surface of the wire. The valve metal, one example being tantalum, may serve as the electrode wire itself or may surround an inner wire such as stainless steel. By providing an electrode for corona discharge having a uniform high resistive coating, the plasma glow produced will spread uniformly along the length of the wire. By using a valve metal, which form a hard oxide under the high resistivity coating, the electrode is self-healing in that if cracks or imperfections occur in the coating, the exposed valve metal will oxidize and fill in the cracks and imperfections.</p> |
