Electric blower

Abstract

An electric blower includes: a rotor that includes a rotary shaft; a centrifugal fan that includes a first opening and is attached to the rotary shaft; a fan case that includes a second opening and covers the centrifugal fan, the second opening including an opening end that is located outside an opening end of the first opening; and a fan case spacer that includes a third opening and is attached to the fan case, the third opening being in communication with the first opening. The fan case spacer includes: a spacer part that closes off a gap between the opening end of the first opening and the opening end of the second opening; and a cover part that extends outward from the opening end of the second opening and covers an outer surface of the fan case. The cover part includes a protrusion that is annular, protrudes toward the outer surface of the fan case, and surrounds the second opening. The protrusion is located between the opening end of the second opening and a tip part of the cover part and is in contact with the outer surface of the fan case.

1 . An electric blower comprising:
 a rotor that includes a rotary shaft;   a centrifugal fan that includes a first opening and is attached to the rotary shaft;   a fan case that includes a second opening and covers the centrifugal fan, the second opening including an opening end that is located outside an opening end of the first opening; and   a fan case spacer that includes a third opening and is attached to the fan case, the third opening being in communication with the first opening,   wherein the fan case spacer includes: a spacer part that closes off a gap between the opening end of the first opening and the opening end of the second opening; and a cover part that extends outward from the opening end of the second opening and covers an outer surface of the fan case,   the cover part includes a protrusion that is annular, protrudes toward the outer surface of the fan case, and surrounds the second opening, and   the protrusion is located between the opening end of the second opening and a tip part of the cover part and is in contact with the outer surface of the fan case.   
     
     
         2 . The electric blower according to  claim 1 , wherein the protrusion is inclined along the outer surface of the fan case. 
     
     
         3 . The electric blower according to  claim 2 , wherein the protrusion is curved to extend outward from the third opening. 
     
     
         4 . The electric blower according to  claim 2 , wherein the protrusion is in a tapered shape. 
     
     
         5 . The electric blower according to  claim 1 , wherein the tip part of the cover part includes a first pressure contact surface that adheres annularly to the outer surface of the fan case, the first pressure contact surface surrounding the second opening. 
     
     
         6 . The electric blower according to  claim 5 , wherein the cover part includes a pressure contact part located between the opening end of the second opening and the protrusion, and the pressure contact part includes a second pressure contact surface that is annularly in pressure contact with the outer surface of the fan case, the second pressure contact surface surrounding the second opening. 
     
     
         7 . The electric blower according to  claim 1 , wherein the fan case spacer includes a fixing part for fixing the fan case spacer to the fan case. 
     
     
         8 . The electric blower according to  claim 7 , wherein the fixing part is welded to the opening end of the second opening. 
     
     
         9 . The electric blower according to  claim 8 , wherein the fixing part is welded to the opening end of the second opening by ultrasonic welding. 
     
     
         10 . The electric blower according to  claim 8 , wherein the fixing part includes a thermoplastic resin.