Blower and cleaner

Abstract

A blower includes an impeller that rotates around a central axis extending in an up-down direction; a motor that is disposed at one side in the up-down direction with respect to the impeller, and rotates the impeller; a motor housing that houses the motor; a fan casing that houses the impeller and the motor housing, and forms a first flow passage between the fan casing and the motor housing; and a substrate disposed at the one side in the up-down direction with respect to the impeller. One and the other end portions in the up-down direction of the fan casing respectively have first and second openings communicating with one another via the first flow passage. A capacitor is disposed on the substrate, at least a portion of the capacitor overlapping the first flow passage in plan view.

What is claimed is: 
     
         1 . A blower comprising:
 an impeller that rotates around a central axis extending in an up-down direction;   a motor that is disposed at one side in the up-down direction with respect to the impeller, and rotates the impeller;   a motor housing that houses the motor;   a fan casing that houses the impeller and the motor housing, and forms a first flow passage between the fan casing and the motor housing; and   a substrate disposed at the one side in the up-down direction with respect to the impeller,   wherein one end portion and the other end portion in the up-down direction of the fan casing respectively have a first opening and a second opening, the first opening communicating with the second opening via the first flow passage, a capacitor being disposed on the substrate, and   wherein at least a portion of the capacitor overlaps the first flow passage in plan view.   
     
     
         2 . The blower according to  claim 1 ,
 wherein the first flow passage has a curved portion extending in the up-down direction and outward in a radial direction from an outer end portion in the radial direction of the impeller, and an extending portion communicating with the curved portion and extending in the up-down direction.   
     
     
         3 . The blower according to  claim 1 ,
 wherein the capacitor is disposed on a surface at the other side in the up-down direction of the substrate.   
     
     
         4 . The blower according to  claim 2 ,
 wherein the capacitor is disposed on a surface at the other side in the up-down direction of the substrate.   
     
     
         5 . The blower according to  claim 1 ,
 wherein the motor housing has a cylindrical portion forming the first flow passage and extending in the up-down direction, and at least a portion of the capacitor is disposed at an inner side in the radial direction of the cylindrical portion in plan view.   
     
     
         6 . The blower according to  claim 1 ,
 wherein the motor housing has a cylindrical portion forming the first flow passage and extending in the up-down direction, and a position in the radial direction of an outer end in the radial direction of the capacitor is aligned with a position in the radial direction of an outer surface in the radial direction of the cylindrical portion in plan view.   
     
     
         7 . The blower according to  claim 1 ,
 wherein a plurality of stator blades are disposed in a circumferential direction on an outer surface of the motor housing.   
     
     
         8 . The blower according to  claim 7 ,
 wherein at least a portion of the capacitor faces at least one of the stator blades in the up-down direction.   
     
     
         9 . The blower according to  claim 1 ,
 wherein the motor housing has a motor-housing recess recessed in the up-down direction, and at least a portion of the capacitor is housed in the motor-housing recess.   
     
     
         10 . The blower according to  claim 1 ,
 wherein the motor housing has an inlet port extending therethrough in the radial direction and communicating with the first flow passage.   
     
     
         11 . The blower according to  claim 1 ,
 wherein a field-effect transistor is disposed on a surface of the substrate on which the capacitor is disposed, at a position near the capacitor.   
     
     
         12 . A cleaner comprising the blower according to  claim 1 .