Fan motor

Abstract

An outer rotor fan motor includes a stator, a shaft that rotates about a central axis extending vertically, a bearing that supports the shaft to be rotatable with respect to the stator, and an impeller that is connected to the shaft via a shaft housing. The shaft includes a heat pipe extending in an axial direction. The shaft housing is connected to the shaft, extends in a radial direction, and is made of metal.

What is claimed is: 
     
         1 . An outer rotor fan motor comprising:
 a stator;   a shaft that rotates about a central axis extending vertically;   a bearing that supports the shaft to be rotatable with respect to the stator; and   
       an impeller that is connected to the shaft via a shaft housing; wherein
 the shaft includes a heat pipe extending in an axial direction; and 
 the shaft housing is connected to the shaft, extends in a radial direction, and is made of metal. 
 
     
     
         2 . The fan motor according to  claim 1 , wherein a diameter of the heat pipe is equal to or longer than about ½ of a diameter of the shaft. 
     
     
         3 . The fan motor according to  claim 1 , wherein an axial length of a connection portion between the shaft and the shaft housing is longer than a diameter of the shaft. 
     
     
         4 . The fan motor according to  claim 1 , wherein a diameter of the shaft housing is equal to or longer than twice a diameter of the shaft. 
     
     
         5 . The fan motor according to  claim 1 , wherein
 the impeller includes an impeller lid portion that is connected to the shaft housing and extends in the radial direction; and   a diameter of the shaft housing is equal to or longer than about ½ of a diameter of the impeller lid portion.   
     
     
         6 . The fan motor according to  claim 1 , wherein the heat pipe opposes the shaft housing in the radial direction over a length equal to or longer than about ½ of an axial length of the connection portion between the shaft and the shaft housing. 
     
     
         7 . The fan motor according to  claim 1 , wherein a surface extending in the radial direction of the shaft housing includes a concavo-convex portion. 
     
     
         8 . The fan motor according to  claim 1 , wherein the stator is covered with a resin. 
     
     
         9 . The fan motor according to  claim 1 , wherein the bearing is a sleeve bearing.