Image forming apparatus

An image forming apparatus, comprising:

• an image carrier on which an electrostatic latent image is formed;
• a developing device provided corresponding to the image carrier, the developing device including:
• a developing container for accommodating a two-component developer including magnetic carrier and toner;
• a developer carrier rotatably supported in the developing container;
• an agitation member that agitates and conveys the developer in the developing container;
• a supply member that agitates and conveys the developer received from the agitation member and supplies the developer to the developer carrier;
• a developer supply port through which the developer is supplied into the developing container;
• and
• a developer discharge portion that discharges surplus part of the developer out of the developing container,
• the developing device developing the electrostatic latent image formed on the image carrier into a toner image,
• an image forming section including the image carrier and the developing device;
• and
• a developer recovery mechanism that has a connection portion connected to the developer discharge portion, and recovers the surplus part of the developer discharged from the developing device,
• the image forming section being capable of selectively incorporating either one of
• a first developing device employing a first developing method where toner is caused to adhere to a surface of the image carrier by means of a magnetic brush formed on the developer carrier and
• a second developing device having a toner carrier disposed between the developer carrier and the image carrier, and employing a second developing method where a toner layer is formed on a surface of the toner carrier by means of a magnetic brush formed on the developer carrier and toner is caused to adhere to the surface of the image carrier by means of the toner layer formed on the toner carrier,
• the first developing device and the second developing device, in a state of being installed in the image forming device, have a same positional relationship of the developer discharge portion with respect to a rotation shaft of the image carrier.