Blower fan

Abstract

A blower fan includes a motor unit including a rotary unit; a plurality of blades fixed to an outer surface of the rotary unit and arranged to be rotated about a center axis by the motor unit; and a lower plate portion defined by a magnetic body and positioned below the motor unit and the blades. The lower plate portion includes a motor fixing portion, a curved portion, a peripheral portion, and a plurality of ribs arranged to interconnect the motor fixing portion and the peripheral portion either directly or through the curved portion, the curved portion including a standing portion extending upward from the outer edge portion of the motor fixing portion and an upper surface portion extending radially outward from an upper end of the standing portion, a plurality of openings positioned below the blades being defined by the curved portion, the peripheral portion, and the ribs.

1 . A blower fan, comprising:
 a motor unit including a rotary unit;   a plurality of blades fixed to an outer surface of the rotary unit of the motor unit and arranged to be rotated about a center axis by the motor unit; and   a lower plate portion defined by a magnetic body and positioned below the motor unit and the blades; wherein   the lower plate portion includes a motor fixing portion to which the motor unit is fixed, a curved portion provided in an outer edge portion of the motor fixing portion, a peripheral portion, and a plurality of ribs arranged to interconnect the motor fixing portion and the peripheral portion either directly or through the curved portion;   the curved portion is arranged below a rotor magnet of the rotary unit to annularly extend about the center axis, the curved portion including a standing portion extending upward from the outer edge portion of the motor fixing portion and an upper surface portion extending radially outward from an upper end of the standing portion, a plurality of openings positioned below the blades being defined by the curved portion, the peripheral portion, and the ribs.   
     
     
         2 . The blower fan of  claim 1 , further comprising a sidewall portion arranged to cover sides of the blades, the sidewall portion including a lower end portion fixed to the peripheral portion. 
     
     
         3 . The blower fan of  claim 1 , further comprising an upper plate portion positioned above the motor unit and the blades, the upper plate portion being made of metal or resin. 
     
     
         4 . The blower fan of  claim 2 , further comprising an upper plate portion positioned above the motor unit and the blades, the upper plate portion being made of resin and continuously joined to the sidewall portion. 
     
     
         5 . The blower fan of  claim 3 , wherein the upper plate portion includes an intake port axially overlapping with the blades and the motor unit. 
     
     
         6 . The blower fan of  claim 1 , wherein the ribs extend radially outward from the upper surface portion of the curved portion. 
     
     
         7 . The blower fan of  claim 3 , wherein the ribs are angled downward as the ribs extend radially outward. 
     
     
         8 . The blower fan of  claim 1 , wherein the curved portion further includes a descending portion extending down from a radial outer end portion of the upper surface portion, the ribs extending radially outward from a lower end of the descending portion. 
     
     
         9 . The blower fan of  claim 6 , wherein the ribs are perpendicular or substantially perpendicular to the center axis. 
     
     
         10 . The blower fan of  claim 1 , wherein the ribs extend radially outward from the motor fixing portion, the curved portion being provided in the outer edge portion of the motor fixing portion between the ribs. 
     
     
         11 . The blower fan of  claim 1 , wherein each of the blades includes a lower edge including a straight portion extending from the outer surface of the rotary unit in a direction perpendicular or substantially perpendicular to the center axis, the upper surface portion including a radial outer end portion radially positioned between a radial outer end point of the straight portion and an outer surface of the rotor magnet or radially positioned to coincide with the outer surface of the rotor magnet. 
     
     
         12 . The blower fan of  claim 11 , wherein the radial outer end portion of the upper surface portion is positioned radially between the outer surface of the rotary unit and the outer surface of the rotor magnet or radially positioned to coincide with the outer surface of the rotary unit or the outer surface of the rotor magnet. 
     
     
         13 . The blower fan of  claim 1 , wherein each of the blades includes a lowermost portion positioned lower than the upper surface portion of the curved portion. 
     
     
         14 . The blower fan of  claim 13 , wherein the motor fixing portion is positioned higher than the peripheral portion. 
     
     
         15 . The blower fan of  claim 1 , wherein the curved portion includes a portion extending upward from a radial outer end portion of the upper surface portion. 
     
     
         16 . The blower fan of  claim 15 , wherein the portion extending upward from the radial outer end portion of the upper surface portion is positioned radially outward of the rotor holder. 
     
     
         17 . The blower fan of  claim 1 , wherein the motor unit further includes a circuit board arranged above the motor fixing portion, the motor fixing portion including hole portions or cutout portions into which electronic parts mounted to the circuit board are inserted. 
     
     
         18 . The blower fan of  claim 1 , wherein the motor unit further includes a circuit board arranged above the motor fixing portion, the outer edge portion of the motor fixing portion including a curved portion nonexistence region in which the curved portion is not provided, the circuit board including an integrated circuit positioned within the curved portion nonexistence region.