| 摘要 |
PURPOSE:To perform an excellent heat treatment with less power consumption and to obtain excellent fixability by heating at least one of the 1st and the 2nd rotating bodies in a heat developing device, etc. CONSTITUTION:The heating value of a heater 3 is 0-200% corresponding to respective heat generation zones and heat generation parts and has a projection at the center part on the whole. Using this heater 3 allows heat movement from the center part of a heating roll 1 to the end parts and a temperature distribution which is nearly uniform on the whole is obtained on the heating roll 1. When fixing operation is carried out in this state, no abnormal temperature rises occurs to the roll end parts even if the temperature of the heating roll drops owing to a toner image and a recording material, and the surface temperature of the heating roll is held at necessary temperature for the fixation by the heater 3. On the other hand, sleeves 15a and 15b made of heat insulating materials are fitted where bearings 12c and 12d for supporting both ends of a pressurizing roll 2 pressed against the heating roll rotatably contacts the roll and the sleeves 15a and 15b are wider than the contacting width of the bearings 12c and 21d, so even if the pressurizing roll 2 shifts in position slightly to left or right, the loss of heat conduction from end parts of the pressurizing roll 2 is eliminated. |
