Patent ID: 7512355

Claim:
An ozone exhaust system for use in an image forming apparatus including a plurality of process printing units, each of said process printing units creating a separated color image corresponding to a color of color-separated image information, comprising: shielding members each enclosing an electric field generating element of one of the process printing units and each extending from one side end to another side end of the electric field generating element; and exhaust passages each connected to one of the shielding members and exhausting ozone generated in the shielding members, wherein the exhaust passages include a plurality of process printing unit side exhaust passages provided for the respective shielding members, and a main exhaust passage to which the process printing unit side exhaust passages are connected, wherein each of the printing unit's side exhaust passages has a respective joint with the main exhaust passage, an exhaust fan at an exhaust outlet of the main exhaust passage, wherein the exhaust outlet is aligned between two of the joints with the printing unit's side exhaust passages, and at least one of the two joints for the process printing unit's side exhaust passages directs air current into the main exhaust passage to flow in the same direction as the air current flowing through the shielding members connected to the process printing unit's side exhaust passages and another of the two joints directs the air current through a joint duct slanted at an acute angle with respect to a flow direction of air through the shielding member connected to the process printing unit's side exhaust passage having the joint duct.