Patent ID: 9671711
Date: 2017-06-06
CPC Classifications: G03G

Claim:
1. An image forming apparatus comprising: a plurality of image forming units provided for each of a plurality of colors, each of the image forming units including a photosensitive body and a plurality of types of processing components around the photosensitive body, and forming an image in the corresponding color by electrophotographic system; a high-voltage power supply circuit capable of generating a bias voltage for the processing components of the same type based on a voltage output from a first transformer; and a control unit that controls a first printing mode using a predetermined number of the image forming units, and a second printing mode using a smaller number of the image forming units than the predetermined number, wherein in the second printing mode, the control unit performs such control that the photosensitive bodies provided on the image forming units not used in the second printing mode continuously rotate at a speed lower than a speed in the first printing mode, and such control that a bias voltage whose absolute value is less than an absolute value of a bias voltage in the first printing mode is supplied from the high-voltage power supply circuit to the processing components of the same type provided on the image forming units not used in the second printing mode, and wherein the high-voltage power supply circuit is capable of simultaneously generating different bias voltages for the processing components of the same type.