| 摘要 |
PROBLEM TO BE SOLVED: To provide a belt driving device capable of suppressing fluctuation of belt moving speed with a high precision.SOLUTION: A belt driving device performs driving control of an intermediate transfer belt by detecting a rotation angular speed ωa of a driven roller 15, of rollers 14, 15, 16, 18, 22 over which the intermediate transfer belt 20 is hung and controlling rotation driving speed of the driving roller 14 on the basis of the detected rotation angular speed. Therein, the rotation driving speed of the driving roller is controlled by correcting the detected rotation angular speed on the basis of an amplitude and a phase of rotation speed fluctuation which have such a period as to have an integer ratio relation (N times or 1/N times; N=natural number) to one rotation period of the driven roller. Diameter of the driven roller has a non-integer ratio relation to a diameter of a rotator around which the intermediate transfer belt is wound, of other rollers which are brought into contact with the inner circumferential surface of the intermediate transfer belt. |
