Patent ID: 7815039

Claim:
A belt skew correction device comprising: a belt skew correcting roller that corrects skew of an endless belt by being brought into contact with the endless belt that is wound between a driving roller and a driven roller; a driving body that performs a driving operation which causes the skew correcting roller to incline in a direction for correcting the skew of the endless belt, wherein a rate change of the incline in the direction for correcting the skew of the endless belt is non-linear and varies in association with a rate at which the driving body is driven, such that the rate of change of the inline when there is a small skew and the driving body is driven at a smaller rate is less than the rate of change of the incline when there is a large skew and the driving body is driven at a larger rate; and a sensor which detects the skew of the endless belt; a control device that drives the driving body based on the detection of the sensor, wherein a driving state of the driving body is maintained for a predetermined period of time after the sensor detects a skew in the endless belt, and wherein the control device drives the driving body for an additional period of time if the skew is not reduced when the predetermined period of time elapses.