Fixing device and control method used therein

摘要

A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, a temperature detector, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween. The heater is disposed adjacent to the fuser member to heat the fuser member. The temperature detector is directed to at least one of the fuser member, the pressure member, and the heater to detect an operational temperature of the fixing device. The controller is operatively connected to the temperature detector and the heater to control power supply to the heater according to readings of the temperature detector, so as to regulate the detected operational temperature at a setpoint temperature that is variable depending on a print page printed on the recording medium.

主权项

1. A fixing device comprising:
a rotatable fuser member subjected to heating; a rotatable pressure member opposite the rotatable fuser member, the rotatable pressure member being configured to press against the rotatable fuser member to form a fixing nip there between, a recording medium being conveyed through the fixing nip; a heater adjacent to the rotatable fuser member and configured to heat the rotatable fuser member; a temperature detector directed to at least one of the rotatable fuser member, the rotatable pressure member, and the heater, the temperature detector being configured to detect an operational temperature of the fixing device; and a controller connected to the temperature detector and the heater and configured to control power supply to the heater according to readings of the temperature detector, so as to regulate the detected operational temperature at a setpoint temperature that is variable depending on a print page printed on the recording medium, wherein during sequential processing of multiple print pages, including a current print page and a previous print page immediately preceding the current print page, the controller controls the power supply by adjusting the setpoint temperature for the current print page to,
a primary temperature determined based on image information of the current print page when the primary temperature is equal to or higher than the setpoint temperature used to print the previous print page, anda secondary temperature higher than the primary temperature when the primary temperature is lower than the setpoint temperature used to print the previous print page.