Fan motor

Abstract

A fan motor includes a static body, a rotating body that has a shaft, a hub encircling a first end of the shaft and joined with the first end, and a blade joined around an outer periphery of the hub, a sleeve that retains thereinside a portion of the shaft at a second end side, a rotating flange which encircles the sleeve and which rotates together with the hub, a static flange which is disposed in an area at a side of the first end of the shaft, and which is joined with the static body so as to overlap the rotating flange in a radial direction, a dynamic pressure generating groove provided in either one of surfaces of the static body and the rotating body facing with each other in the axial direction, and a lubricant present between the static body and the rotating body.

What is claimed is: 
     
         1 . A fan motor comprising:
 a static body including a base;   a rotating body which includes a shaft, a hub encircling a first end of the shaft and joined with the first end, and a blade joined around an outer periphery of the hub, and which rotates relative to the static body;   a sleeve which retains thereinside a portion of the shaft at a second end side and which is joined with the base;   a rotating flange which encircles at least a portion of the sleeve and which rotates together with the hub;   a first static flange which is disposed in an area at a side of the first end of the shaft in an axial direction and which faces the rotating flange in the axial direction;   a second static flange which is disposed in an area at a side of the second end of the shaft in the axial direction and which faces the rotating flange in the axial direction;   a first dynamic pressure generating groove that is provided in either one of surfaces of the rotating flange and the first static flange facing with each other in the axial direction;   a second dynamic pressure generating groove that is provided in either one of surfaces of the rotating flange and the second static flange facing with each other in the axial direction; and   a lubricant present between the static body and the rotating body.   
     
     
         2 . The fan motor according to  claim 1 , wherein the rotating flange is located outwardly of a portion of the sleeve retaining the shaft in a radial direction. 
     
     
         3 . The fan motor according to  claim 1 , wherein the rotating flange is located at an area close to the first end of the shaft rather than the second end thereof in the axial direction. 
     
     
         4 . The fan motor according to  claim 1 , wherein the rotating flange is located in an area at the side of the first end of the shaft beyond a weighted center of the rotating body in the axial direction. 
     
     
         5 . The fan motor according to  claim 1 , wherein the rotating flange is joined with the hub. 
     
     
         6 . The fan motor according to  claim 1 , wherein the first static flange is joined with the sleeve. 
     
     
         7 . The fan motor according to  claim 1 , further comprising a radial dynamic pressure groove provided in either one of an outer periphery of the shaft and an inner periphery of the sleeve. 
     
     
         8 . The fan motor according to  claim 1 , further comprising a housing which is joined with the second static flange and which encircles the sleeve. 
     
     
         9 . The fan motor according to  claim 8 , wherein
 the base is provided with a base hole where the housing is inserted to fasten the housing, and   the fan motor further comprising a welded part that joins an edge of the base hole with the housing.   
     
     
         10 . The fan motor according to  claim 1 , further comprising:
 a magnet joined with the hub; and   a magnetic member which is joined with the static body and which suctions the magnet toward the base.   
     
     
         11 . The fan motor according to  claim 1 , further comprising:
 a first cylinder part joined with the hub; and   a second cylinder part encircled by and joined with the first cylinder part and having an inner periphery holding an air-liquid interface of the lubricant.   
     
     
         12 . The fan motor according to  claim 11 , wherein the second cylinder part and the rotating flange are joined together in a seamless manner. 
     
     
         13 . The fan motor according to  claim 1 , further comprising:
 a stator core including a core encircling part, core teeth running outwardly of the radial direction from the core encircling part and each having a coil, and a core tip running outwardly of the radial direction from the core teeth;   a core holder that joins the stator core and the base; and   a ring magnet which encircles the stator core, is joined with the hub, and has a magnetic polarity at a surface facing the core tip in the radial direction.   
     
     
         14 . The fan motor according to  claim 13 , further comprising a spacer present between the core tip and the base in the axial direction. 
     
     
         15 . A fan motor comprising:
 a static body including a base;   a rotating body which includes a shaft, a hub encircling a first end of the shaft and joined with the first end, and a blade joined around an outer periphery of the hub, and which rotates relative to the static body;   a sleeve which retains thereinside a portion of the shaft at a second end side and which is joined with the base;   a rotating flange which encircles at least a portion of the sleeve and which rotates together with the hub;   a static flange which is disposed in an area at a side of the first end of the shaft in an axial direction with reference to the rotating flange and which is joined with the static body so as to overlap with the rotating flange in the radial direction;   a dynamic pressure generating groove which is disposed outwardly of a portion of the sleeve retaining the shaft in the radial direction and which is provided in either one of surfaces of the static body and the rotating body facing with each other in the axial direction; and   a lubricant present between the static body and the rotating body.   
     
     
         16 . The fan motor according to  claim 15 , wherein the rotating flange is located outwardly of a portion of the sleeve retaining the shaft in a radial direction. 
     
     
         17 . The fan motor according to  claim 15 , wherein the rotating flange is located at an area close to the first end of the shaft rather than the second end thereof in the axial direction. 
     
     
         18 . The fan motor according to  claim 15 , wherein the rotating flange is located in an area at the side of the first end of the shaft beyond a weighted center of the rotating body in the axial direction. 
     
     
         19 . The fan motor according to  claim 15 , wherein the static flange is joined with the sleeve. 
     
     
         20 . A fan motor comprising:
 a static body including a base;   a rotating body which includes a shaft, a hub encircling a first end of the shaft and joined with the first end, and a blade joined around an outer periphery of the hub, and which rotates relative to the static body;   a sleeve which retains thereinside a portion of the shaft at a second end side and which is joined with the base;   a rotating flange which encircles at least a portion of the sleeve and which rotates together with the hub;   a static flange which is disposed in an area at a side of the first end of the shaft in an axial direction with reference to the rotating flange, and which is joined with the static body so as to overlap the rotating flange in a radial direction;   a dynamic pressure generating groove provided in either one of surfaces of the static body and the rotating body facing with each other in the axial direction; and   a lubricant present between the static body and the rotating body.