| 摘要 |
PURPOSE:To definitely control the surface temp. of a roller and obtain uniformity of temp. by forming a revolvable roller with a heating element having positive resistance temp. characteristics of nonlinear type, supplying voltage to this and maintaining the roller temp. definitely. CONSTITUTION:Electrodes 12, 13 are formed on the inside surface and outside surface of a roller 11 consisting of a heating element, and a heat roller 10 can be maintained at the temp. of set temp. TD by applying constant voltage through their terminals 14, 15. Namely, this simply necessitates setting the voltage to be applied to the roller 11 in such a manner that the set temp. TD is attained. Hence, there is no need for intricate circuits such as heat sensitivie elements, temp. control circuit or the like, and the surface temp. of the roller 11 is maintained at the set temp. simply by providing the constant voltage source. |
