HEATING DEVICE, HEAT FIXING DEVICE AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To lessen the temperature unevenness in a nip part ant to prevent the heat treatment defect by the temperature unevenness by respectively, independently and electrically controlling heating element patterns according to the results of the temperature detection with temperature detecting elements disposed near the top of the heater surfaces. SOLUTION: An AIN substrate 12c having good thermal conductivity of a heating element which is a heater for heating of the heating device is formed with electrical heating elements 12a and 12b by baking an Ag.Pd paste in prescribed patterns by layer thickness printing and the surfaces of the element are provided with a glass coating layer. Chip-like thermistors 14 are adhered and fixed on the electrode patterns previously formed by film thickness printing in the regions where both of the electrical heating elements 12a and 12b exist on the surface of the substrate 12c on the side opposite to the surface formed with the heating elements, by which the heater substrate temperature is monitored. The broad electrical heating elements 12a are arranged downstream B of the nip part and the narrow electrical heating elements 12b are arranged upstream A of the nip part. The electrical heating elements 12a and 12b are respectively, independently and electrically controlled according to the results of the temperature detection with the thermistors 14.