Fixing device control method and apparatus, fixing device, and image forming machine

摘要

In a photoelectrographic image forming machine of the power saving type, a temperature rise tendency calculating unit calculates a tendency of temperature rise in terms of an amount of temperature rise per unit time during the normal operation mode, and a temperature calculating unit calculates a lowest temperature of the heating unit during the power saving mode in terms of a temperature such that a duration till the temperature of the heating unit reaches the target fixing temperature is a desired period during which the image forming machine restores the normal operation mode from the power saving mode. A fixing temperature control unit keeps the temperature of a heating unit not less than the lowest temperature during the power saving mode. The result is that the restoration period can be kept not more than the maximum period the user can be patient to wait.