Fixing device with mechanism capable of detecting pressure exerted between opposed components and image forming apparatus incorporating same

摘要

A fixing device includes a pressurization member connected to a pressing rotary body to press the pressing rotary body against a fixing rotary body; a depressurization assembly interposed between the pressing rotary body and the pressurization member and movable between a reduced pressure position where the depressurization assembly causes the pressurization member to press the pressing rotary body against the fixing rotary body with reduced pressure therebetween and an enhanced pressure position where the depressurization assembly is free from pressure from the pressurization member to cause the pressurization member to press the pressing rotary body against the fixing rotary body with enhanced pressure therebetween; a positioner separatably contacting the depressurization assembly to immovably halt the depressurization assembly at the enhanced pressure position; and a position detector separatably contacting the depressurization assembly to detect the position of the depressurization assembly.

主权项

1. A fixing device comprising:
a fixing rotary body rotatable in a set 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 pressurization member connected to the pressing rotary body to press the pressing rotary body against the fixing rotary body; a depressurization assembly installed at an end of the fixing device in an axial direction and interposed between the pressing rotary body and the pressurization member and movable between a reduced pressure position where the depressurization assembly causes the pressurization member to press the pressing rotary body against the fixing rotary body with reduced pressure therebetween and an enhanced pressure position where the depressurization assembly is free from pressure from the pressurization member to cause the pressurization member to press the pressing rotary body against the fixing rotary body with enhanced pressure therebetween; a positioner contacting the depressurization assembly to immovably halt the depressurization assembly at the enhanced pressure position; and a position detector contacting the depressurization assembly to detect the position of the depressurization assembly, wherein the fixing rotary body, the pressing rotary body, the pressurization member and the depressurization assembly are inside a housing, and the positioner and the position detector are outside of the housing.