Textured contact rollers and the method of using them for improving electrical contact with a fuser belt fusing

摘要

Three fuser rollers cooperate with a pressure roller to form an extended fusing zone through which an electrically resistive substrate carrying toner images passes with the toner images contacting fusing belt. Electrical power is applied to the three fuser rolls in such a manner that only the portions of the belt between the rollers are heated. The energy is concentrated only in the part of the fusing belt where it is needed for fusing the toner images on the final substrate. Thus free extent of the belt or in other words the portion of the belt outside of the fusing zone remains unheated. To ensure good electrical contact in the presence of silicone oil contamination on the inner surface of the fusing belt the contact rollers are textured by knurling, bead blasting or other suitable techniques. Such treatment produces high and low surface areas, the former providing the good electrical contact.