Centrifugal fan and air conditioner having the same

Abstract

A centrifugal fan, which equally maintains air-blowing capacities of both inlets regardless of different suction resistances of both inlets due to a driving device, and an air conditioner having the centrifugal fan. The centrifugal fan includes a rotary plate; first blades disposed at the edge of one surface of the rotary plate; and second blades disposed at the edge of the other surface of the rotary plate, and having a larger outer diameter than the outer diameter of the first blades. Thus, although a large flow resistance is generated at one inlet of the centrifugal fan due to the driving device, air-blowing capacities of both inlets are maintained equally.

1 . A centrifugal fan comprising:
 a rotary plate;   first blades disposed at the edge of one surface of the rotary plate; and   second blades disposed at the edge of the other surface of the rotary plate, and having a larger outer diameter than the outer diameter of the first blades.   
   
   
       2 . The centrifugal fan according to  claim 1 , wherein the height of the second blades is larger than the height of the first blades. 
   
   
       3 . The centrifugal fan according to  claim 1 , wherein the inner diameter of the first blades is smaller than the inner diameter of the second blades. 
   
   
       4 . The centrifugal fan according to  claim 1 , wherein the outer diameter of the first blades is smaller than the diameter of the rotary plate. 
   
   
       5 . The centrifugal fan according to  claim 4 , wherein the first blades and the second blades are respectively disposed in a ring shape at the edges of the surfaces of the rotary plate. 
   
   
       6 . A centrifugal fan comprising:
 a rotary plate; and   a pair of first and second inlets disposed in opposite to each other in the axial direction of the rotary plate such that air is sucked to the centrifugal fan in both directions,   wherein the suction region of the second inlet is wider than the suction region of the first inlet.   
   
   
       7 . The centrifugal fan according to  claim 6 , further comprising a pair of first and second outlets in the radial direction of the rotary plate,
 wherein the discharge region of the second outlet is wider than the discharge region of the first outlet.   
   
   
       8 . The centrifugal fan according to  claim 7 , further comprising a first shroud connected to the outer edges of the first blades and a second shroud connected to the outer edges of the second blades,
 wherein the outer diameter of the second shroud is larger than the outer diameter of the first shroud.   
   
   
       9 . An air conditioner, which has a centrifugal blowing unit to forcibly blow air, the centrifugal blowing unit comprising:
 a centrifugal fan including a rotary plate;   first blades disposed at the edge of one surface of the rotary plate;   second blades disposed at the edge of the other surface of the rotary plate, and having a larger outer diameter than the outer diameter of the first blades; and   a driving device disposed at the second blades to provide rotary force to the rotary plate.   
   
   
       10 . The air conditioner according to  claim 9 , wherein the rotary plate is connected directly to a rotary shaft of the driving device. 
   
   
       11 . The air conditioner according to  claim 9 , wherein the height of the second blades is larger than the height of the first blades. 
   
   
       12 . The air conditioner according to  claim 10 , wherein the inner diameter of the first blades is smaller than the inner diameter of the second blades.