Patent ID: 7486916

Claim:
An image forming apparatus, comprising: an intermediate transfer belt; a plurality of cartridges disposed at intervals under the intermediate transfer belt, each of which includes at least a developer container; at least one detachable toner storage configured to include a toner exit arranged at a position which is above a side position of the intermediate transfer belt; and at least one toner supplying unit configured to convey toner from the at least one detachable toner storage to the developer container included in one of the plurality of cartridges through a toner conveying passage, wherein the toner conveying passage includes a first position arranged at a side position of the intermediate transfer belt to convey toner from an upper portion to a lower portion thereof, and a second position arranged at a portion between a lower portion of the intermediate transfer belt and an upper portion of the cartridge to convey toner in a horizontal direction.