Patent ID: 8571448

Claim:
An image forming apparatus comprising: a plurality of developing devices aligned in a predetermined direction, wherein each of the plurality of developing devices comprises: a developing chamber comprising an opening; a developing agent storage chamber disposed above the developing chamber, wherein the developing agent storage chamber is configured to supply developing agent to the developing chamber; a developing roller configured to be exposed by the opening of the developing chamber; a supplying roller disposed adjacent to the developing roller, wherein the supplying roller is configured to supply the developing agent to the developing roller; a first conveying unit disposed within the developing chamber in a vicinity of the supplying roller, wherein the first conveying unit is configured to convey the developing agent in a longitudinal direction of the developing roller so as to supply the developing agent to the supplying roller; a second conveying unit disposed within the developing agent storage chamber, wherein the second conveying unit is configured to convey the developing agent in a longitudinal direction of the developing roller so as to supply the developing agent to the first conveying unit; a partition wall provided between the first conveying unit and the second conveying unit; a first conveying path for conveying the developing agent from the developing agent storage chamber to the developing chamber; and a second conveying path for conveying the developing agent from the developing chamber to the developing agent storage chamber; wherein in the plurality of developing devices, the first conveying path is configured to convey the developing agent from up to down in a vertical direction, and the second conveying path is configured to convey the developing agent from down to up in the vertical direction.