Belt conveying device, fixing device, image forming device

Abstract

The present invention provides a belt conveying device that controls the belt's position based on the belt's position detected by a sensor, thereby suppressing belt meandering caused by the temperature of the sensor. [Solution] The feedback gain of the control system for belt-side control is corrected by capturing the change in the output characteristics of the sensor unit 390 caused by temperature. Using the first voltage VPD1 and the second voltage VPD2 output from the sensor unit 390, which change depending on the end position of the fixing belt, the subtraction unit 33 calculates a differential value "VPD1-VPD2" indicating the end position of the fixing belt, and the addition unit 34 calculates a sum value "VPD1+VPD2" that reflects the change in the amount of light emitted by the light-emitting unit. Then, the "steering operation amount STEPn" calculated by the PID calculation unit 31 according to the differential value "VPD1-VPD2" is corrected by a gain correction coefficient determined by the gain determination unit 35 based on the sum value "VPD1+VPD2" to determine the tilt angle of the steering roller.

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