Image forming apparatus

An image forming apparatus comprising:

• a rotatable photosensitive member;
• a charging member configured to electrically charge said photosensitive member;
• a developing device including a developer carrying member for carrying a developer and configured to develop a latent image formed on said photosensitive member;
• a blade configured to clean said photosensitive member;
• and
• a controller configured to execute a predetermined operation in which during continuous image formation for continuously forming images on a plurality of recording materials, the image formation is interrupted and an interval between consecutive recording materials is increased, and then said photosensitive member is rotated,
• wherein during the predetermined operation, said controller executes a first predetermined operation and then executes a second predetermined operation,
• wherein in the first predetermined operation, said photosensitive member is rotated through one full circumference or more on the following conditions:
• (i) a voltage which is a discharge start voltage or higher is applied to said charging member, and
• (ii) an operation condition of said developing device is a first condition,
• wherein on the first condition, an amount of fog toner deposited from said developer carrying member on said photosensitive member is less than an amount of the fog toner on a second condition which is an operation condition of said developing device during a sheet interval step before the image formation during the continuous image formation is interrupted, and
• wherein, in the second predetermined operation, said photosensitive member is rotated on the following conditions:
• (i) to said charging member, a voltage is not applied or a voltage which is lower than the discharge start voltage is applied, and
• (ii) an operation condition of said developing device is a third condition, and
• wherein in the third condition, the amount of the fog toner deposited from said developer carrying member on said photosensitive member is less than an amount of the fog toner in the second condition.

An image forming apparatus comprising:

• a plurality of image forming portions each including a rotatable photosensitive member, a charging member for electrically charging a surface of said photosensitive member, a charging power source for applying a voltage to said charging member, an exposure portion for forming an electrostatic image on the charged surface of said photosensitive member by exposing the charged surface of said photosensitive member to light, a rotatable developing member for forming a toner image on the surface of said photosensitive member by supplying toner to the electrostatic image, a cleaning member for removing the toner from the surface of said photosensitive member in contact with the surface of said photosensitive member, a driving portion for driving said photosensitive member, and a detecting portion for detecting a value correlating with a driving torque of said photosensitive member by said driving portion;
• a transfer device configured to transfer the toner image formed on said photosensitive member of each of said plurality of image forming portions;
• and
• a controller capable of executing an operation, in at least one image forming portion of said plurality of image forming portions during continuous image formation in which image formation for forming the toner image transferred onto a recording material is continuously carried out for transferring the toner images onto a plurality of recording materials, wherein the image formation is interrupted and a voltage generating discharge between said charging member and said photosensitive member is applied to said charging member, and then said photosensitive member is rotated through at least one full circumference in a state in which rotation of said developing member is stopped or in a state in which said developing member is rotated at a rotational speed lower than a rotational speed during the image formation,
• wherein said controller discriminates, at a predetermined timing during the continuous image formation, whether or not a detection result of said detecting portion acquired with time shows that the driving torque has lowered so as to satisfy a predetermined condition, and in a case that discrimination that the detection result shows that the driving torque has lowered in at least one image forming portion of said plurality of image forming portions is made, said controller executes the operation in said at least one image forming portion, and
• wherein in the image forming portion of said plurality of image forming portions in which discrimination that the detection result does not show that the driving torque has lowered is made at the predetermined timing, said controller executes the image formation or executes another operation in which the image formation is interrupted and a voltage is not applied to said charging member or a voltage which does not generate the discharge between said charging member and said photosensitive member is applied to said charging member and in which said photosensitive member is rotated through at least one full circumference in the state in which rotation of said developing member is stopped or in the state in which said developing member is rotated at the rotational speed lower than the rotational speed during the image formation.