| 摘要 |
PROBLEM TO BE SOLVED: To enhance efficiency of an axial flow fan switchable in the blowing direction in two directions. SOLUTION: A casing 1 is equipped internally with impellers 3a and 3b on both sides of a motor 2 of reversible type about the rotating direction, and the air flow can be switched between A and B in accordance with the rotating direction of the motor 2. In the case of the direction A, a jet flow consisting of the component in the direction A and the circumferential direction velocity component in the rotating direction of each blade 4b blows out with rotation of the blades 4b of the front stage impeller 3b, where the motor 2 is held by a small diameteric stay 7, etc., in the air flow passages of the impellers 3a and 3b, so that the circumferential direction velocity component is not obstructed substantially, and the jet flow is sent to the rear stage impeller 3b while it contains the described components mostly. Because the impeller 3b rotates in the same direction and at the same speed as the impeller 3a, it scarcely applies the work to the air flow but is sent out in the direction A.
|
