An image forming apparatus includes a rotatable image bearing member, a developing member, a transfer member, and a brush contacting a surface of the image bearing member in a contact portion downstream of a transfer portion and upstream of a developing portion with respect to a rotational direction of the image bearing member. The toner which is not transferred onto a toner image receiving member is collected by the developing member. In a charging series, the toner is positioned on the same side as a normal charge polarity of the toner relative to the brush. In the contact portion, a maximum value of a contact pressure of 0.7 gf/mm.sup.2 or more and 3.5 gf/mm.sup.2 or less, a maximum contact area ratio is 18% or more and 74% or less, and a Clark-Evans index of the brush is 1 or more.

A cleaning device that cleans a surface of an image holding unit capable of holding an image formed using an image forming material includes: a cleaning tool that is movable along an intersecting direction intersecting with a moving direction of the image holding unit and cleans the surface of the image holding unit when placed in a contact position where the cleaning tool is in contact with the surface of the image holding unit; and a guiding unit that guides the cleaning tool so that the cleaning tool moves from a non-contact position where the cleaning tool is not in contact with the image holding unit to the contact position for cleaning the surface of the image holding unit, wherein when the image holding unit is moved, the cleaning tool placed in the contact position cleans the surface of the image holding unit.

An image forming apparatus includes an image bearing member, a charger, a static eliminating section, and a determination section. The image bearing member includes a photosensitive layer. The charger charges a circumferential surface of the image bearing member. The static eliminating section eliminates static electricity from the charged circumferential surface of the image bearing member. The determination section determines whether or not static electricity is to be eliminated from the circumferential surface of the image bearing member based on a thickness of the photosensitive layer. The image forming apparatus includes a measurement section and an estimation section. The measurement section measures a drive time or the number of rotations of the image bearing member. The estimation section estimates the thickness of the photosensitive layer based on a result of measurement by the measurement section.

An image forming apparatus using a contact charging method includes a control unit capable of executing cleaning in a post-rotation step at the end of a job and in an inter-image step during execution of the job. The cleaning involves moving toner adhering to a charging member from the charging member to an image bearing member. The job is a series of operations started by a predetermined start instruction and involving forming an image on one or more recording materials and outputting the one or more recording materials. When an instruction to start the next job is input during execution of cleaning in the post-rotation step, the control unit stops the cleaning in the middle of the execution, starts the next job, and adjusts timing for executing subsequent cleaning on the basis of information relating to the amount of cleaning executed before being stopped in the middle of the execution.

An image forming apparatus includes a developing cartridge, a drum cartridge, a casing, a connector, and a controller. The drum cartridge includes a photosensitive drum, a drum cartridge memory, a charger, and a cleaner. The charger is configured to charge the photosensitive drum and including a wire and a grid electrode. The cleaner is configured to clean the wire. The connector is configured to be electrically connected to the drum cartridge memory. Information is writable to the drum memory through the connector. The detection circuit board is configured to detect a state of discharge of the charger. The controller is configured to perform: determining whether or not the state of discharge detected by the detection circuit board is abnormal; and writing, in the drum cartridge memory, information representing occurrence of the abnormal discharge through the connector in a case where occurrence of the abnormal discharge is determined.

An image forming apparatus includes first and second image bearing members; first and second charging members; first and second developing members; a transfer member configured to sequentially transfer toner images from the first and second image bearing members to a transfer-receiving member; and a control portion configured to, at a timing determined based on information relating to the toner image formed on the first image bearing member, perform a cleaning operation of decreasing toner that adheres to the second charging member at a time of non-image formation.

The pixels counting unit divides an area in a main-scanning direction of a recording material on which image formation is performed into a plurality of areas 1 to n based on a width that is a length in the main-scanning direction of the recording material, and measures a pixels count with respect to each area among the plurality of areas 1 to n defined by dividing the area in the main-scanning direction of the recording material.

An example lubricant coating device includes a rotatable applicator to apply lubricant from a solid lubricant source to a member to be coated, and a supporting device to support the solid lubricant source in a contact state with the rotatable applicator. The supporting device changes a supporting angle of the solid lubricant source relative to the rotatable applicator when a consumption of the solid lubricant source reaches a consumption threshold.

A charging member includes a conductive substrate, an elastic layer disposed on the conductive substrate, and a surface layer disposed on the elastic layer. Regarding the surface of the surface layer, in the axial direction, the ratio of the mean spacing of profile irregularities Sm to the ten-point mean roughness Rz and the reduced peak height Spk respectively satisfy 15Sm/Rz35 and Spk5 m.

A charging device includes: a charging member that is rotatable and has a peripheral surface to be in contact with a charging target and to which a voltage is to be applied for charging the charging target; a removing member that includes a core and a removing material spirally wound one to less than two times around the core and rotates and comes into contact with the charging member to remove an unnecessary material from the peripheral surface of the charging member; and a detecting unit that detects a current flowing between the charging member and the removing member.