Patent ID: 7322881

Claim:
An exhaust device suitably used to exhaust air from an inside of a target apparatus to an outside thereof, comprising: a louver that includes a plurality of blades arrayed in a lattice, the louver being selectively lockable and detachably engaged with a peripheral wall portion of a through hole portion of a cover of the target apparatus and having a plurality of concave portions on an edge portion of said peripheral wall such that the louver can rotate freely in any of a clockwise direction and a counterclockwise direction when unlocked; and a fan unit positioned upstream in an airflow direction from the louver, wherein the fan unit is provided separately from the louver such that the fan unit does not rotate when the louver is rotated, wherein the blades form an angle between 0° and 90° with a plane that is perpendicular to a central axis of the louver, wherein the louver includes locking pawls that are selectively lockable with and detachably engaged with the concave portions of the peripheral wall of the through hole portion of the cover when the louver is engaged with the through hole portion of the cover.