Abstract: An image forming apparatus includes an image carrier that holds an image, a developer carrier that holds a developer to be supplied to the image carrier, a transport member that transports the developer in an axial direction of the developer carrier, and a restraint member that restrains the developer, which has scattered as a result of being transported by the transport member, from moving toward the developer carrier.

Abstract: An image forming apparatus includes: an image carrier that carries an image; a transport-path forming part that forms a transport path for developer used to develop the image carried by the image carrier; a transport member that transports the developer in the transport path; and a concentration detector that detects toner concentration in the developer in the transport path. The transport path includes a first portion and a second portion. Difference in sectional area between the second portion and the transport member in a direction intersecting a direction in which the developer is transported is smaller than difference in sectional area between the first portion and the transport member. The second portion is located downstream of the first portion in the direction in which the developer is transported. The concentration detector is disposed in the second position of the transport path.

Abstract: An image forming apparatus includes an image carrier that holds an image, a developer carrier that holds a developer to be supplied to the image carrier, a transport member that transports the developer in an axial direction of the developer carrier, and a restraint member that restrains the developer, which has scattered as a result of being transported by the transport member, from moving toward the developer carrier.

Abstract: A developing device includes a developing sleeve and a regulation portion. The developing sleeve includes a magnetism generating portion to which magnetic poles are attached. The developing sleeve holds a developer on an outer circumferential surface. The regulation portion includes a magnetic plate. A first segment connecting a peak position of the magnetic pole disposed at a position facing the magnetic plate and an axial center of the developing sleeve has an angle, with respect to a second segment connecting the magnetic plate and the axial center, equal to or less than 7 degrees on a downstream side in a rotation direction of the developing sleeve and equal to or less than 6 degrees on an upstream side in the rotation direction. An angle of a half value width of the magnetic pole is equal to or greater than 41 degrees to equal to or less than 52 degrees.