Centrifugal fan

Abstract

Disclosed herein is a centrifugal fan. The centrifugal fan includes a back plate having a central portion for coupling with a rotation center shaft, a plurality of blades extending from the back plate, and a shroud which is connected to end portions of the blades and has an introduction end portion and a discharge end portion through which fluid passes, and the discharge end portion is rounded with a predetermined curvature in a direction away from the back plate.

1 . A centrifugal fan comprising:
 a back plate having a central portion for coupling with a rotation center shaft;   a plurality of blades extending from the back plate; and   a shroud having a circular ring shape and connected to end portions of the blades, wherein the shroud comprises:   an introduction end portion through which fluid is introduced;   a connection portion curved to have a diameter that gradually increases from the introduction end portion; and   a discharge end portion through which the fluid is discharged via the connection portion, and   wherein the discharge end portion is rounded in a direction away from the back plate.   
     
     
         2 . The centrifugal fan according to  claim 1 , wherein the discharge end portion has a larger curvature than the connection portion. 
     
     
         3 . The centrifugal fan according to  claim 2 , wherein the curvature of the discharge end portion is equal to or more than a single arc (1arc). 
     
     
         4 . The centrifugal fan according to  claim 1 , wherein the back plate comprises a connection portion which extends in a radial direction of the back plate from the central portion and connects the central portion to a circumferential portion, and the circumferential portion is rounded in a direction away from the discharge end portion of the shroud. 
     
     
         5 . The centrifugal fan according to  claim 4 , wherein a distance between the discharge end portion of the shroud and the circumferential portion of the back plate is gradually increased in a discharge direction of the fluid. 
     
     
         6 . The centrifugal fan according to  claim 4 , wherein the discharge end portion of the shroud and the circumferential portion of the back plate form a diffuser. 
     
     
         7 . The centrifugal fan according to  claim 1 , wherein the central portion protrudes toward the introduction end portion. 
     
     
         8 . The centrifugal fan according to  claim 7 , wherein the back plate is continuously rounded from the central portion to the circumferential portion of the back plate. 
     
     
         9 . A centrifugal fan comprising:
 a back plate having a central portion for coupling with a rotation center shaft;   a plurality of blades extending from the back plate; and   a shroud having a circular ring shape and connected to end portions of the blades,   wherein the shroud comprises:   an introduction end portion through which fluid is introduced;   a connection portion curved to have a diameter that gradually increases from the introduction end portion; and   a discharge end portion through which the fluid is discharged via the connection portion, and   wherein the discharge end portion of the shroud and a circumferential portion of the back plate are rounded in opposite directions to each other.   
     
     
         10 . The centrifugal fan according to  claim 9 , wherein the discharge end portion of the shroud and the circumferential portion of the back plate are rounded in directions away from each other. 
     
     
         11 . The centrifugal fan according to  claim 9 , wherein the central portion protrudes toward the introduction end portion. 
     
     
         12 . The centrifugal fan according to  claim 9 , wherein the back plate is continuously rounded from the central portion to the circumferential portion of the back plate.