Fixing device and image forming apparatus incorporating same

摘要

A fixing device includes a fixing rotary body rotatable in a given direction of rotation and a pressing rotary body pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed inside the fixing rotary body to heat the fixing rotary body. A reflector, disposed opposite an inner circumferential surface of the fixing rotary body via the heater, reflects light emitted from the heater onto the fixing rotary body. The reflector includes a movable portion movable relative to the heater to direct the light emitted from the heater onto a variable heating span of the fixing rotary body spanning in an axial direction thereof. The variable heating span varies depending on a width of the recording medium in the axial direction of the fixing rotary body.

主权项

1. A fixing device comprising:
a fixing rotary body rotatable in a given direction of rotation; a pressing rotary body pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed; a heater disposed inside the fixing rotary body to heat the fixing rotary body; and a reflector, disposed opposite an inner circumferential surface of the fixing rotary body via the heater, to reflect light emitted from the heater onto the fixing rotary body, the reflector including:
a movable portion movable relative to the heater to direct the light emitted from the heater onto a variable heating span of the fixing rotary body spanning in an axial direction thereof, the variable heating span varying depending on a width of the recording medium in the axial direction of the fixing rotary body, wherein the movable portion of the reflector is movable between a parallel position where the movable portion is parallel to the heater and a first angled position where the movable portion is angled relative to the heater with an increased interval therebetween, andwherein the movable portion of the reflector is movable further to a second angled position where the movable portion is angled relative to the heater with a decreased interval therebetween.