PURPOSE: To maintain the uniform temp. distribution over the entire part of a heating roll embeded with a heat source and to prevent the uneven fixing of a copy with respect to a roll fixing device to be used for an electrophotographic copying machine, etc. by forming recesses, projecting parts or holes at specified intervals by drawing, etc. to the circumferential edge at the end of one heating roll and connecting the same to a gear, etc. of a driving system.

CONSTITUTION: The roll 1 which is formed to a piece of cylindrical shape has a meshing part 2 at the circumferential edge at the end which is meshed with a gear 6 connecting to a driving source such as driving motor. The roll rotates when operated by the driving source. A press contact roll is brought into press contact with such roll 1 and a material to be treated such as copying paper is passed therebetween. The meshed part may be depressed to be formed into the recesses or may be made into the projecting parts or may be bored with holes by a boring machine. The roll is integrally produced by working a cylindrical pipe to the shape to be meshed with the gear, etc. of the driving system. The temp. distribution on the surface of such roll is uniform without difference between the end of the roll meshed with the driving system and the central part. The uniformity of the temp. distribution is maintained even if the copying is continuously executed. The sharp copy is thus obtd. without uneven fixing.