FIXING DEVICE FOR ELECTROPHOTOGRAPHIC PRINTER

摘要

PROBLEM TO BE SOLVED: To provide a small and low-cost fixing device for an electrophotographic printer which is free of thermal breakage on a heat roller surface and can perform high-speed printing by thermal fixation with stable high temperature setting. SOLUTION: The fixing device is constituted by arranging two temperature detectors detecting the surface temperature of a heat roller and the heat roller includes one main heating element which always operates and two subordinate heating elements. The fixing device selects and operates one of the two subordinate heating elements according to information obtained by a form size detector detecting the size of a form in use and independently controls the respective heating elements according to detection information of the temperature detectors corresponding to the heating elements. Here, the ratio of the heating range of the main heating element, the heating range of one subordinate heating element, and the heating range of the other subordinate heating element is 2:2:1 to 10:2:1 and the ratio of outputs is 2:2:1 to 16:2:1. COPYRIGHT: (C)2004,JPO&NCIPI