Impeller, blower, and vacuum cleaner

Abstract

An impeller is rotatable about a vertically extending central axis and includes a base portion extending radially outward as it extends downward, first blades circumferentially arrayed on the upper surface of the base portion and extending on one side in the circumferential direction as it extends upward, and second blades between the circumferential direction of the circumferentially adjacent first blades and extending on one side in the circumferential direction as it extends upward. The radial outer end of the second blade is on one side in the circumferential direction relative to the middle in the circumferential direction of the radial outer end of the circumferentially adjacent first blade.

What is claimed is: 
     
         1 . An impeller that is rotatable about a vertically extending central axis, the impeller comprising:
 a base portion extending radially outward as it extends downward;   a plurality of first blades circumferentially arrayed on an upper surface of the base portion and extending on one side in a circumferential direction as it extends upward; and   a plurality of second blades between a circumferential direction of the circumferentially adjacent first blades and extending on one side in a circumferential direction as it extends upward; wherein   a radial outer end of the second blade is on one side in a circumferential direction relative to a middle in a circumferential direction of a radial outer end of the circumferentially adjacent first blade.   
     
     
         2 . The impeller according to  claim 1 , wherein a radial inner edge of the first blade extends upward as it extends radially outward. 
     
     
         3 . The impeller according to  claim 1 , wherein a radial outer edge of the first blade extends upward as it extends radially outward. 
     
     
         4 . The impeller according to  claim 1 , wherein when the first blade is viewed from a radial outward, an upper portion of an upper edge of the first blade is a curved surface protruding to another side in a circumferential direction, and a lower portion of the upper edge of the first blade is a curved surface protruding to the one side in the circumferential direction. 
     
     
         5 . The impeller according to  claim 1 , wherein a radial inner edge of the second blade extends upward as it extends radially outward. 
     
     
         6 . The impeller according to  claim 1 , wherein a radial outer edge of the second blade extends upward as it extends radially outward. 
     
     
         7 . The impeller according to  claim 1 , wherein in a planar view, the radial inner edge of the second blade is on the one side of the circumferential direction as it extends radially outward. 
     
     
         8 . The impeller according to  claim 1 , wherein when the second blade is viewed from a radial outward direction, an upper edge of the second blade is a curved surface protruding to the one side in the circumferential direction. 
     
     
         9 . The impeller according to  claim 1 , wherein in a planar view, a radial inner edge of the first blade extends along an imaginary line radiating from a central axis. 
     
     
         10 . The impeller according to  claim 9 , wherein in a planar view, a radial outer end at a radial inner edge of at least one of the second blades is on the imaginary line. 
     
     
         11 . The impeller according to  claim 1 , wherein when the impeller is viewed from a radial outward direction, an upper end of the second blade is located above an axial midpoint between an upper end of the first blade and a lower end of the first blade. 
     
     
         12 . The impeller according to  claim 1 , wherein in a planar view, a minimum value of a radius of curvature in a first connection region of the base portion and a surface of another side in a circumferential direction of the first blade is smaller than a minimum value of a radius of curvature in a second connection region of the base portion and a surface of another side in a circumferential direction of the second blade. 
     
     
         13 . The impeller according to  claim 1 , wherein radial outer ends of the first blade are located at equal intervals in a circumferential direction, and radial outer ends of the second blade are located at equal intervals in a circumferential direction. 
     
     
         14 . A blower, comprising
 the impeller according to  claim 1 .   
     
     
         15 . A vacuum cleaner, comprising
 the blower according to  claim 14 .