Axial fan and electrical device

Abstract

Embodiments of the disclosure provide an axial fan and an electrical device. A center of a radial inner surface and a center of a radial outer surface of a cylindrical portion of a housing of the axial fan are disposed at different positions.

What is claimed is: 
     
         1 . An axial fan, comprising:
 a motor comprising a shaft rotatable about a central axis;   an impeller fixed to the shaft; and   a housing comprising a cylindrical portion disposed on a radial outer side of the impeller and extending in an axial direction,   wherein   a center of an axial projection of a radial inner surface of the cylindrical portion is a first center, the first center being located on the central axis, and   a center of an axial projection of a radial outer surface of the cylindrical portion is a second center, the second center being at a position different from a position of the first center in a direction perpendicular to the central axis.   
     
     
         2 . The axial fan according to  claim 1 , wherein
 in the direction perpendicular to the central axis, a radial width of a first region of the cylindrical portion that is disposed on a second center side based on the first center is greater than a radial width of a second region of the cylindrical portion that is disposed on an opposite side of the second center based on the first center, and   a housing recess that is recessed in the axial direction is formed in the first region.   
     
     
         3 . The axial fan according to  claim 2 , wherein
 a plurality of housing recesses are formed in a circumferential direction.   
     
     
         4 . The axial fan according to  claim 3 , wherein
 a first rib is disposed between the plurality of housing recesses.   
     
     
         5 . The axial fan according to  claim 2 , wherein
 the housing further comprises:   a base that overlaps with the motor in the axial direction; and   a second rib connecting the base and the radial inner surface of the cylindrical portion, wherein   the second rib and the housing recess are provided at different positions in a circumferential direction.   
     
     
         6 . The axial fan according to  claim 2 , wherein
 in a direction toward an air outlet of the axial fan, the radial inner surface of the first region of the cylindrical portion inclines in a direction away from the central axis.   
     
     
         7 . The axial fan according to  claim 1 , wherein
 the cylindrical portion comprises a cylindrical inner wall extending in the axial direction, and a cylindrical outer wall that is disposed on a radial outer side of the inner wall and extends in the axial direction,   the inner wall comprises the radial inner surface, and the outer wall comprises the radial outer surface, and   the inner wall and the outer wall are connected by a third rib extending in a radial direction.   
     
     
         8 . The axial fan according to  claim 1 , wherein
 the housing further comprises:   an edge portion extending to the radial outer side from an end of the cylindrical portion that is close to an air outlet of the axial fan in the axial direction, and   a center of an axial projection of the edge portion is the second center.   
     
     
         9 . An electrical device, comprising the axial fan according to  claim 1 .