Fixing device and image forming apparatus

摘要

A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.

主权项

1. A fixing device comprising:
a fixing rotary body rotatable in a predetermined direction of rotation; a heater disposed opposite and heating the fixing rotary body; an opposed body contacting the fixing rotary body to form a nip therebetween through which a recording medium is conveyed; a heat shield movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater, the heat shield not circular in the circumferential direction of the fixing rotary body and extending substantially throughout a conveyance span of the fixing rotary body in an axial direction thereof where the recording medium is conveyed; and an overheating suppressor interposed between the heater and the heat shield to shield the heat shield from the heater, the heat shield including an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.