Thermal fixing roller for use in a copying machine and method for manufacturing the same.

摘要

A thermal fixing roller for use in a copying machine and a method for manufacturing the thermal fixing roller are disclosed. An insulator layer is formed on an outer surface of a cylindrical metallic pipe, a masking wire material is wound in a spiral manner on the surface of the insulator layer, a heat-generating resistor is formed by spray coating heat-generating resistor material on the surface of these, there after the wire material is removed to leave a groove at its trace, and thereby the above-mentioned heat-generating resistor can be formed in a spiral shape. By choosing pitches at the opposite end portions of this spiral resistor smaller than that at the central portion thereof, uniform temperature is maintained over the entire length of the thermal fixing roller. Also by forming a cross-section configuration of the masking wire material in a rectangular shape, it is allowed to reduce the width of the above-mentioned groove to minimum.