Turbo fan and air conditioner having the same

Abstract

A turbo fan including backward-inclined blades that are inclined in a direction opposite to a rotating direction of a rotating plate. A positive pressure surface of each blade, facing the rotating direction of the rotating plate, takes the form of a flat surface, and a negative pressure surface of the blade, opposite to the rotating direction of the rotating plate, takes the form of a convexly-curved surface. A radius of curvature defined by the convexly-curved negative pressure surface is within a range of 2.5˜4 times of a radius of the turbo fan. The turbo fan can reduce noise and consumption of power together, and consequently, an air conditioner having the turbo fan can achieve an improvement in performance.

1 . A turbo fan comprising:
 a rotating plate connected with a drive unit;   blades radially arranged on the rotating plate; and   a ring-shaped shroud mounted to face one surface of the rotating plate, wherein a positive pressure surface of each blade facing a rotating direction of the rotating plate takes the form of a flat surface, and a negative pressure surface of the blade facing opposite to the rotating direction of the rotating plate takes the form of a convexly-curved surface.   
   
   
       2 . The turbo fan according to  claim 1 , wherein a radius of curvature defined by the convexly-curved negative pressure surface is within a range of 2.5˜4 times a radius of the turbo fan. 
   
   
       3 . The turbo fan according to  claim 1 , wherein the blades take the form of backward-inclined blades, which are inclined in a direction opposite to the rotating direction of the rotating plate. 
   
   
       4 . An air conditioner comprising:
 a body having an air suction opening and an air discharge opening;   a heat exchanger provided in the body and adapted to perform heat exchange of air suctioned through the suction opening; and   a turbo fan including a rotating plate connected with a drive unit, blades radially arranged on the rotating plate, and a ring-shaped shroud mounted to face one surface of the rotating plate, the turbo fan serving to suction the air from the suction opening and blow the suctioned air toward the heat exchanger,   wherein a positive pressure surface of each blade, facing a rotating direction of the rotating plate, takes the form of a flat surface, and a negative pressure surface of the blade, opposite to the rotating direction of the rotating plate, takes the form of a convexly-curved surface.   
   
   
       5 . The air conditioner according to  claim 4 , wherein a radius of curvature defined by the convexly-curved negative pressure surface is within a range of 2.5˜4 times of a radius of the turbo fan. 
   
   
       6 . The air conditioner according to  claim 4 , wherein the blades take the form of backward-inclined blades, which are inclined in a direction opposite to the rotating direction of the rotating plate. 
   
   
       7 . A turbo fan, comprising:
 a rotating plate to connect to a drive member;   a plurality of blades connected at one side to the rotating plate and inclined in a direction opposite to a rotating direction of the rotating plate, each of the blades being shaped to have one curved surface; and   a ring shaped shroud connected to opposite sides of each of the plurality of blades from the side connected to the rotating plate.   
   
   
       8 . A turbo fan according to  claim 7 , wherein a positive pressure surface of each blade takes a form of a flat surface and a negative pressure surface of each blade takes a form of a curved surface. 
   
   
       9 . An air conditioner comprising:
 a body having an air suction opening and an air discharge opening;   a heat exchanger provided in the body and adapted to perform heat exchange of air suctioned through the suction opening; and   a turbo fan to suction the air from the suction opening and blow the suctioned air toward the heat exchanger, the turbo fan including:
 a rotating plate to connect to a drive member, 
 a plurality of blades connected at one side to the rotating plate and inclined in a direction opposite to a rotating direction of the rotating plate, each of the blades being shaped to have one curved surface, and 
 a ring shaped shroud connected to opposite sides of each of the plurality of blades from the side connected to the rotating plate.