Minolta Company, Ltd.

Ichiro Bessho

Takahiro Tsujimoto

Akira Takasu

Teruhiko Fujikura

Hideki Matsuura

Rotational force of a driving motor is transferred to a photosensitive drum via a planetary-roller reduction device, so that the photosensitive drum is rotated. A speed detector set on the shaft of the photosensitive drum detects the rotational speed of the photosensitive drum. In accordance with the detected rotational speed of the photosensitive drum, the rotational speed of the driving motor is adjusted so that the photosensitive drum is rotated at a constant speed.

Rotator driving device, image forming apparatus using the rotator driving device, and method of driving rotator

This invention concerns an automatic exposure adjusting apparatus which permits infallible production of a signal corresponding exactly to the density of a given original document constantly even when the components of an optical system thereof cause any dispersion or gradual deterioration due to aging. First, the apparatus exposes a standard white subject copy 1 set on a document table 2 to the light of a preset standard amount of exposure, samples the reflected light from the copy 1 by a light detector 14, and adjusts to a proper magnitude the output value of an original document density signal emitted from a noninverting amplifier 33. Then, it exposes the standard density plate 3 to the light of an adjusted standard amount of exposure, samples the reflected light from the standard density plate 3 by the light detector 14, and readjusts to a proper magnitude the output value of an original document density signal issued from the noninverting amplifier 33. By this procedure, the apparatus is enabled to produce infallibly an original document of a proper density constantly.

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Aichi-ken, Japan

Ichiro Bessho