| 摘要 |
PROBLEM TO BE SOLVED: To reduce noise level around 8N on the low frequency side and fluctuation thereof as well as noise level due to primary sound of rotation by constituting the angular interval for the rotary shaft of a plurality of blades of a cross- flow fan of a value determined based on a logistic mapping. SOLUTION: The blade 12 of a cross-flow fan 3 extends from one end to the other end of a plurality of supporting discs 13 arranged, at a substantially constant interval, in the direction of the rotary shaft of the cross-flow fan 3, i.e., from the left end to the right end on the drawing, and one blade 12 penetrates each supporting disc 13. Each blade 12 uniformly forms so-called skew, i.e., an inclination for advancing the drive side (motor side) more than the driven side in the rotational direction ω. Consequently, noise level due to primary sound of rotation is reduced, noise level around 8N on the low frequency side and fluctuation thereof are also reduced, resulting in an air conditioner where low noise is realized without imposing uncomfortableness to a listener. |
