FAN

PROBLEM TO BE SOLVED: To provide thin-shaped fan with little noise, having a long range of blown air current. SOLUTION: This crossflow fan comprises an impeller 2 with blade width not more than a half of its outer diameter. The impeller 2 is included by a fan casing 4. In a portion of the fan casing closest to the outer peripheral part of the impeller 2 on the flowing-out side, starting from a tongue 24 to a part of 60-80 degree of rotation angle therefrom, a gap 25 between the casing 4 and the outer peripheral part of the impeller 2 is set to about 4% of the impeller outer diameter with a single R. An inlet port 7 starts from the end of the closest portion to a part of 100-120 degree of the rotation angle therefrom. A gap 29 larger than the gap 25 between the tongue 24 and the outer peripheral part of the impeller 2 is formed from the end of the inlet port 7. The scroll enlarging rate is set to 0.3% from there, and the gap between the outer peripheral part of the impeller 2 and the fan casing is gradually enlarged up to an outlet port 6. The size of the outlet port 6 is set not more than about 80% of the effective suction area of the inlet port 7. COPYRIGHT: (C)2004,JPO