Patent ID: 9195174
Filing Date: 2015-11-24
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a rotatable photosensitive member; a charging device that charges the photosensitive member; an exposure device that exposes the charged photosensitive member to form an electrostatic latent image on the photosensitive member; a developing device that supplies toner to the photosensitive member to develop an electrostatic latent image on the photosensitive member as a toner image; a common power supply that applies voltage to the charging device and the developing device; a movable rotary member that forms a transfer portion with the photosensitive member to receive the toner image from the photosensitive member or to convey a recording material that receives the toner image; a moving unit that effects relative movement between the developing device and the photosensitive member between a first position for developing the electrostatic latent image and a second position in which the developing device is further away from the photosensitive member than in the first position; a determination unit that determines whether a relative position when the photosensitive member starts rotating is the first position or the second position; and a control unit configured to perform a control of potential at the transfer portion, wherein in a case where the determination unit determines that the relative position when the photosensitive member starts rotating is the first position, during a period after the common power supply starts outputting and before a charge area charged by the charging device on the photosensitive member reaches the transfer portion, the control unit controls the potential at the transfer portion to be a potential of a same polarity as a charged polarity of the toner.