US Patent 7596331 Image forming apparatus

An image forming apparatus includes an auxiliary charging member contacting an image bearing member and for being supplied with a bias of an identical polarity to a normal charge polarity of toner at a position downstream from a transfer portion where a transfer member is located and upstream from a charging portion where a charging member is located with respect to a rotation direction of the image bearing member. When rotation of the image bearing member is stopped and then resumed, application of a toner transfer bias to the transfer member is started before a contact position between the image bearing member and the auxiliary charging member during the rotation stop of the image bearing member first reaches the transfer portion.