A developing apparatus includes a developer bearing member bearing a developer on a surface in a developing operation, a regulating member configured to regulate layer thickness of the developer borne on the developer bearing member, a development chamber provided with the developer bearing member and the regulating member and having an opening, a storage chamber to store the developer, and a conveying member to convey the developer stored in the storage chamber to the development chamber through the opening. When the developing operation is performed, a bottom section of the development chamber is located above a bottom section of the storage chamber in a vertical direction, and a contact region of the developer bearing member in contact with the regulating member is located directly above the opening in the vertical direction.

An image forming apparatus includes a sheet feeding unit configured to hold a plurality of sheets, an image forming unit configured to form a toner image on a sheet, and a carrying unit configured to sequentially carry sheets from the sheet feeding unit in a carrying direction towards the image forming unit. A mechanical cleaner is provided to remove extraneous matter from a portion of the image forming unit. A moving mechanism is configured to re-position the sheet along a sheet width direction intersecting the sheet carrying direction. The moving mechanism is on an upstream side of a position along the carrying direction at which the toner image is formed on the sheets.

A drum cleaner in a drum unit removes toner from a photosensitive drum. A waste-toner conveyance pipe has a waste-toner discharge port and conveys toner removed from the photosensitive drum by the drum cleaner. A toner accommodation chamber accommodates toner to be supplied to a developing roller. A waste-toner accommodation chamber accommodates toner removed from the photosensitive drum. A toner cartridge rotatably moves relative to the drum unit between: a first position at which a waste-toner receiving port is separated from the waste-toner discharge port in a state where the toner cartridge is mounted on the drum unit; and a second position at which an internal space of the waste-toner accommodation chamber is in communication with an internal space of the waste-toner conveyance pipe through the waste-toner discharge port and the waste-toner receiving port in a state where the toner cartridge is mounted on the drum unit.

In an image forming apparatus, the image bearing member has a surface and configured to rotate about an axis. The collection device is in contact with the surface, and configured to collect materials adhered to the surface. The developing roller is configured to provide a charged toner having a first polarity. The processor is configured to perform: executing a print job in a printing period; executing, in a non-printing period, a first process in which the image bearing member is rotated at least one rotation while a holding bias is applied to the collection device, the holding bias having a second polarity opposite to the first polarity; and executing, in a non-printing period after the first process, a second process in which the image bearing member is rotated while an ejection bias is applied to the collection device, the ejection bias having the first polarity.

In a case where a collection mode in which an exposure unit forms a first potential on a photosensitive member and a developing unit collects discharging toner discharged from the developing unit to a position where the first potential is formed is executed, a potential forming unit forms, on an intermediate transfer member, a potential same as a normal charging polarity of toner and an absolute value greater than an absolute value of the first potential, and a charging power supply applies, to a charging member, a voltage having a polarity same as the normal charging polarity and an absolute value greater than an absolute value of the first potential.

An image forming apparatus includes a photosensitive drum for bearing a developer, a charging roller that comes into contact with the photosensitive drum at a different velocity and that charges the photosensitive drum, a transfer roller that transfers a developer image on the photosensitive drum to a recording material, and a developing sleeve that supplies a developer to the photosensitive drum and that recovers a developer on the photosensitive drum after transfer. A detecting device detects information relating to injection charging, and a controller controls an amount of the fogging developer during image formation according to information detected by the detecting device while suppressing the amount of the developer recovered in the developing sleeve.

An image forming apparatus includes a photosensitive drum, first and second charging members, a development member, and first and second charging voltage applying units. The photosensitive drum includes a surface layer constituting a surface of the photosensitive drum. The second charging voltage applying unit applies a second charging voltage to the second charging member. The surface layer of the photosensitive drum has a volume resistivity of 1.0?109 ohm centimeters (?.Math.cm) or more and 1.0?1014 ?.Math.cm or less. The second charging voltage applying unit applies the second charging voltage such that a second potential difference formed between the second charging member and the surface of the photosensitive drum charged by the first charging member is equal to or higher than a discharge starting voltage.

An image forming apparatus including an image bearing member, a charging member, a developing roller, a transfer roller, and a brush configured to be brought into contact with a surface of the image bearing member on a side downstream of a transfer portion and upstream of a charging portion in a rotation direction of the image bearing member and in which, wherein, after the transfer of a developer image onto a transferred member, a developer remaining on the surface of the image bearing member is collected by the developing roller, the brush is disposed such that, in a cross section perpendicular to a rotation axis of the image bearing member, a contact region of the surface of the image bearing member in contact with the brush overlaps a virtual line containing the rotation axis of the image bearing member and extending upward from the rotation axis in a vertical direction.

A charge roller includes, in a surface thereof, recesses that have sizes that are equivalent to or larger than a volume average particle diameter of a toner accommodated in a developing unit and that are capable of collecting the toner retransferred to a photosensitive drum.

An image forming method includes when an image forming device is in a non-image-forming stage, applying voltages to a surface of a photosensitive element and a surface of a developer element of the image forming device to form an electric field. Applying the voltages includes: forming a first potential difference between the photosensitive element and the developer element in a first stage, and forming a second potential difference between the photosensitive element and the developer element in a second stage. When a developer used by the developer element is a negatively charged developer, a direction of the first potential difference and a direction of the second potential difference are in a direction from the developer element to the photosensitive element. When positively charged, the direction of the first potential difference and the direction of the second potential difference are in a direction from the photosensitive element to the developer element.