Image forming apparatus controlling condition of charging brush

An image forming apparatus comprising:

• a rotatable photosensitive member;
• a charging member configured to electrically charge a surface of the photosensitive member at a charging portion;
• a developing device configured to supply toner to the surface of the electrically charged photosensitive member to form a toner image;
• a transfer member configured to transfer the toner image from the photosensitive member to a recording material at a transfer portion;
• a brush contacting the surface of the photosensitive member downstream of the transfer portion and upstream of the charging portion with respect to a rotational direction of the photosensitive member and configured to form a contacting portion;
• a driving source configured to rotatably drive the photosensitive member;
• and
• a control portion configured to control the driving source to execute an image forming process in which the image formation on the recording material is executed, a non-image-forming process in which the photosensitive member is driven to rotate other than in the image forming process, and a post rotation process in which the photosensitive member is rotated without executing the image forming process after executing the image forming process,
• wherein the non-image-forming process occurs between a first recording material and a second recording material on which the image formation is executed following the first recording material, and
• wherein the control portion determines a time of the post rotation process to be executed after executing the image forming process on the second recording material based on history information correlating with a usage amount of the photosensitive member and a time of the first non-image-forming process.

An image forming apparatus comprising:

• a rotatable photosensitive member;
• a charging member configured to electrically charge a surface of the photosensitive member at a charging portion;
• a developing device configured to supply toner to the surface of the electrically charged photosensitive member to form a toner image;
• a transfer member configured to transfer the toner image from the photosensitive member to a recording material at a transfer portion;
• a brush contacting the surface of the photosensitive member downstream of the transfer portion and upstream of the charging portion with respect to a rotational direction of the photosensitive member and configured to form a contacting portion;
• and
• a control portion configured to control a time of non-image-formation which is a time when the photosensitive member is rotating in a period from when a preceding recording material passes through the transfer portion until a succeeding recording material reaches the transfer portion,
• wherein an inter-image time is a time of non-image-formation from when the preceding recording material passes through the transfer portion until the succeeding recording material reaches the transfer portion without stopping rotation of the photosensitive member, and
• wherein the control portion controls to change the time of the non-image-formation from when a last recording material in consecutive image formation, in which the toner image is consecutively transferred to a plurality of recording materials passes through the transfer portion until a succeeding recording material succeeding the last recording material reaches the transfer portion based on history information correlating with a usage amount of the photosensitive member during the consecutive image formation.