A developer conveyance device includes a downward conveyance path in which a developer falls under gravity, a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path, a transport screw disposed in the transverse conveyance path, and a floating member. The transport screw is configured to rotate in a predetermined direction to transport the developer in the transverse direction. The floating member is configured to contact the transport screw rotating in the predetermined direction to float in the downward conveyance path.

An image forming apparatus includes an image bearing member, a cleaning device detachably provided on a main assembly to clean toner remaining on the image bearing member, a main assembly feeding portion detachably provided on the main assembly to feed the toner discharged from the cleaning device, a collecting container detachably provided on the main assembly to collect the toner discharged from the main assembly feeding portion, a control portion, and an operating portion capable of inputting a predetermined instruction to the operating portion. Without an image forming operation based on the predetermined instruction, the control portion performs a discharging operation in which the main assembly feeding portion is caused to be driven to discharge the toner inside of the main assembly feeding portion.

An image forming apparatus includes an image bearing member, a cleaning device detachably provided on a main assembly to clean toner remaining on the image bearing member, a main assembly feeding portion detachably provided on the main assembly to feed the toner discharged from the cleaning device, a collecting container detachably provided on the main assembly to collect the toner discharged from the main assembly feeding portion, a control portion, and an operating portion capable of inputting a predetermined instruction to the operating portion. Without an image forming operation based on the predetermined instruction, the control portion performs a discharging operation in which the main assembly feeding portion is caused to be driven to discharge the toner inside of the main assembly feeding portion.

A target value for a gap between a developer bearing member supported by a developing frame member and a regulating blade that is fixed to the developing frame member is determined based on input information about a local maximum peak value of magnetic flux density of a predetermined magnetic pole which is located closest to the regulating blade when the regulating blade is fixed to the developing frame member among a plurality of magnetic poles included in a magnet fixedly located inside the developer bearing member and configured to generate a magnetic field for causing a developer to be borne by the developer bearing member.

A target value for a gap between a developer bearing member supported by a developing frame member and a regulating blade that is fixed to the developing frame member is determined based on input information about a local maximum peak value of magnetic flux density of a predetermined magnetic pole which is located closest to the regulating blade when the regulating blade is fixed to the developing frame member among a plurality of magnetic poles included in a magnet fixedly located inside the developer bearing member and configured to generate a magnetic field for causing a developer to be borne by the developer bearing member.

An image forming apparatus includes a control unit configured to execute a stop mode in which, after image forming operation is stopped, a developer bearing member is rotated for a predetermined time with a potential difference between a film forming electrode and a developer bearing member set to zero or smaller than that during image formation, and thereafter, the rotation of the developer bearing member is stopped.

An image forming apparatus includes a control unit configured to execute a stop mode in which, after image forming operation is stopped, a developer bearing member is rotated for a predetermined time with a potential difference between a film forming electrode and a developer bearing member set to zero or smaller than that during image formation, and thereafter, the rotation of the developer bearing member is stopped.

A developer conveyance device includes a downward conveyance path in which a developer falls under gravity, a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path, a transport screw disposed in the transverse conveyance path, and a floating member. The transport screw is configured to rotate in a predetermined direction to transport the developer in the transverse direction. The floating member is configured to contact the transport screw rotating in the predetermined direction to float in the downward conveyance path.

A developer conveyance device includes a downward conveyance path in which a developer falls under gravity, a transverse conveyance path communicating with a lower end of the downward conveyance path and extending in a transverse direction intersecting with the downward conveyance path, a transport screw disposed in the transverse conveyance path, and a floating member. The transport screw is configured to rotate in a predetermined direction to transport the developer in the transverse direction. The floating member is configured to contact the transport screw rotating in the predetermined direction to float in the downward conveyance path.

A belt unit includes a belt member, a cleaning member that scrapes off a developer being attached and carried on the belt member, a waste developer accommodation chamber that accommodates the developer as a waste developer, a waste developer carrying member that carries the waste developer accommodated in the waste developer accommodation chamber in correspondence with a rotation thereof; and a waste developer taking-up member that takes up the waste developer in correspondence with a rotation thereof and supplies the waste developer to a contact portion between the cleaning member and the belt member, wherein the waste developer taking-up member is composed with a shaft and a brush attached to the shaft.