Cross-flow fan and air conditioner equipped with same

Abstract

A crossflow fan includes an impeller formed by plate-like blades 42. Each blade 42 is inclined such that the outer edge 42 a is located on the leading side of the inner edge 42 d with respect to the rotation direction of the impeller 41. The face of each blade 42 that is located on the leading side of the rotation direction forms a positive pressure surface 42 p, and a face located on the trailing side forms a negative pressure surface 42 q. Notches 42 b are formed at the outer edge 42 a of the blade 42 . The notches 42 b are arranged at predetermined intervals along the rotation axis of the impeller. The bottom 42 y of the notch 42 b is connected to the positive pressure surface 42 p at a positive pressure corner 42 n and connected to the negative pressure surface 42 q at a negative pressure corner 42 m. The positive pressure corner 42 n and the negative pressure corner 42 m are both rounded.

1 . A crossflow fan comprising an impeller having a plurality of support plates located on a rotation axis of the impeller and a plurality of plate-like blades provided at peripheral portions of the support plates, the blades extending parallel to the rotation axis, each blade being inclined such that its outer edge is located on the leading side of its inner edge with respect to the rotation direction of the impeller, one of the faces of each blade that is on the leading side of the rotation direction of the impeller forms a positive pressure surface, the face on the trailing side of the rotation direction forms a negative pressure surface,
 the crossflow fan being characterized in that a plurality of notches are formed at the outer edge of each blade, the notches being arranged at predetermined intervals along the rotation axis of the impeller,   wherein at least one of a positive pressure corner and a negative pressure corner, which connect the bottom of each notch with the positive pressure surface and the negative pressure surface, respectively, is rounded.   
     
     
         2 . The crossflow fan according to  claim 1 , characterized in that the negative pressure corner, which connects the bottom of each notch with the negative pressure surface, is rounded. 
     
     
         3 . The crossflow fan according to  claim 1  or  2 , characterized in that the positive pressure corner, which connects the bottom of each notch with the positive pressure surface, is rounded. 
     
     
         4 . A crossflow fan comprising an impeller having a plurality of support plates located on a rotation axis of the impeller and a plurality of plate-like blades provided at peripheral portions of the support plates, the blades extending parallel to the rotation axis, each blade being inclined such that its outer edge is located on the leading side of its inner edge with respect to the rotation direction of the impeller, one of the faces of each blade that is on the leading side of the rotation direction of the impeller forms a positive pressure surface, the face on the trailing side of the rotation direction forms a negative pressure surface,
 the crossflow fan being characterized in that a plurality of notches are formed at the outer edge of each blade, the notches being arranged at predetermined intervals along the rotation axis of the impeller,   wherein the bottom of each notch is formed as a smooth curved surface that protrudes as a whole outward of the impeller.   
     
     
         5 . The crossflow fan according to  claim 1 , characterized in that each notch is V-shaped as viewed from the negative pressure surface and the pressure surface of the blade. 
     
     
         6 . An air conditioner characterized by the crossflow fan according to  claim 1 .