Turbo fan

Abstract

Provided is a turbo fan. The turbo fan includes a main plate rotating by a fan motor providing power and a plurality of blades having one ends connected to the main plate, the plurality of blades being disposed along a circumferential direction on the main plate. Each of the plurality of blades includes a first curved part curved in one direction with respect to an extension part and a second curved part curved in the other direction with respect to the extension part. A plurality of projections protruding in one direction from the one end of the blade and a plurality of grooves protruding in the other direction are alternately disposed on the first and second curved parts. Alternatively, the turbo fan includes a main plate rotating by a fan motor providing power, a rotation shaft providing a rotation center of the main plate, a plurality of blades having a blade front end disposed adjacent to the rotation shaft and a blade rear end disposed spaced from the rotation shaft, the plurality of blades being disposed in a circumferential direction on the main plate, and an extension part defined as a virtual line straightly extending from an upper portion of the blade rear end to a lower portion of the blade rear end. Each of the blades includes a first curved part curved in one direction with respect to the extension part, a second curved part curved in the other direction with respect to the extension part, a first flow part defined as a space between the extension part and the first curved part, and a second flow part defined as a space between the extension part and the second curved part.

What is claimed is: 
     
         1 . A turbo fan comprising:
 a main plate rotating by a fan motor providing power; and   a plurality of blades having one ends connected to the main plate, the plurality of blades being disposed along a circumferential direction on the main plate,   wherein each of the plurality of blades comprises:   a first curved part curved in one direction with respect to an extension part; and   a second curved part curved in the other direction with respect to the extension part,   wherein a plurality of projections protruding in one direction from the one end of the blade and a plurality of grooves protruding in the other direction are alternately disposed on the first and second curved parts.   
     
     
         2 . The turbo fan according to  claim 1 , wherein the first and second curved parts are disposed on rear end of the blade, and
 the extension part is defined as a virtual line straightly extending from an upper portion of the rear end of the blade up to a lower portion of the rear end of the blade.   
     
     
         3 . The turbo fan according to  claim 1 , further comprising a shroud connected to the other end of the blade to guide an inflow of air into the blade,
 wherein the blade comprises:   a first contact point at which the main plate and the rear end of the blade meets each other; and   a second contact point at which the shroud and the rear end of the blade meet each other,   wherein the extension part is defined as a virtual line straightly extending from the first contact point up to the second contact point.   
     
     
         4 . The turbo fan according to  claim 1 , wherein the blade further comprises a crossing part defined as a point at which the extension part and the rear end of the blade meet each other,
 wherein the crossing part is defined as a boundary between the first curved part and the second curved part.   
     
     
         5 . The turbo fan according to  claim 4 , wherein the crossing part is defined as a central point of the extension part, and
 the first curved part has a length equal to that of the second curved part.   
     
     
         6 . The turbo fan according to  claim 1 , further comprising:
 an outer circumferential surface that is a virtual line connecting the plurality of projections to each other; and   an inner circumferential surface that is a virtual line connecting the plurality of grooves to each other,   wherein the outer circumferential surface and the inner circumferential surface are disposed parallel to each other.   
     
     
         7 . The turbo fan according to  claim 6 , wherein the outer circumferential surface and the inner circumferential surface have the same curvature. 
     
     
         8 . The turbo fan according to  claim 6 , wherein a vertical distance between the outer circumferential surface and the inner circumferential surface is constant. 
     
     
         9 . The turbo fan according to  claim 6 , wherein the blade comprises:
 a protrusion protruding from the inner circumferential surface toward the inner circumferential surface to constitute one surface of the blade; and   a hollow disposed between the protrusions,   wherein the protrusion and the hollow are alternately disposed with respect to each other.   
     
     
         10 . The turbo fan according to  claim 1 , further comprising a rotation shaft providing a rotation center of the main plate,
 wherein the blade comprises:   a blade front end disposed adjacent to the rotation shaft; and   a blade rear end disposed spaced from the rotation shaft,   wherein the plurality of projections and the plurality of grooves are disposed on the blade rear end.   
     
     
         11 . The turbo fan according to  claim 10 , wherein the plurality of projections and the plurality of grooves protrude from the blade front end toward the blade rear end. 
     
     
         12 . The turbo fan according to  claim 11 , wherein the plurality of curved parts protrude in a direction perpendicular to the protruding direction of the plurality of projections. 
     
     
         13 . The turbo fan according to  claim 12 , wherein each of the plurality of projections and the plurality of grooves has a predetermined curvature. 
     
     
         14 . The turbo fan according to  claim 12 , wherein each of the plurality of projections and the plurality of grooves has a tip. 
     
     
         15 . A turbo fan comprising:
 a main plate rotating by a fan motor providing power;   a rotation shaft providing a rotation center of the main plate;   a plurality of blades having a blade front end disposed adjacent to the rotation shaft and a blade rear end disposed spaced from the rotation shaft, the plurality of blades being disposed in a circumferential direction on the main plate; and   an extension part defined as a virtual line straightly extending from an upper portion of the blade rear end to a lower portion of the blade rear end,   wherein each of the blades comprises:   a first curved part curved in one direction with respect to the extension part;   a second curved part curved in the other direction with respect to the extension part;   a first flow part defined as a space between the extension part and the first curved part; and   a second flow part defined as a space between the extension part and the second curved part.   
     
     
         16 . The turbo fan according to  claim 15 , wherein the blade further comprises a crossing part defined as a point at which the extension part and the blade rear end meet each other,
 wherein the crossing part is defined as a boundary between the first flow part and the second flow part.