US20090038333A1

US20090038333A1 - Turbo fan for blowing and refrigerator having the same

Info

Publication number: US20090038333A1
Application number: US12/280,879
Authority: US
Inventors: Jun-Ho Bae; Chang-joon Kim
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2006-10-19
Filing date: 2006-10-19
Publication date: 2009-02-12
Also published as: CN101529177B; EP1984683A4; WO2008047962A1; EP1984683A1; CN101529177A

Abstract

A turbofan for blowing comprises: a base plate having a hub protruding from a center thereof; a plurality of blades disposed on an outer circumerential surface of the base plate with a constant interval therebetween in a circumferential direction; and a shroud connected to the blades in opposition to the base plate. An outer diameter of a fan, a height of the blade, an inner diameter of the blade, an inner diameter of the shroud, an entrance angle of the blade, etc. are designed with an optimum condition, there by improving a blowing efficiency for cool air and reducing power consumption and noise.

Description

TECHNICAL FIELD

The present invention relates to a turbofan for blowing and a refrigerator having the same, and more particularly, to a turbofan for blowing capable of improving a blowing efficiency for cool air and minimizing power consumption and noise, and a refrigerator having the same.

BACKGROUND ART

In general, a refrigerator serves to store foodstuffs as a freezing state or a refrigerating state by circulating cool air generated by a refrigerating cycle.
As shown in FIG. 1, the conventional refrigerator comprises a body 10 having a freezing chamber 1 and a refrigerating chamber 2, and a door 3 disposed at a front surface of the body 10 for opening and closing the freezing chamber 1 and the refrigerating chamber 2.
As shown in FIG. 2, a turbofan 9 for forcibly blowing air cooled through an evaporator 7 into the freezing chamber 1 is installed at a rear side of the body 10. A shroud 8 for introducing air blown by the turbofan 9 into the freezing chamber 1 is mounted at one side of the turbofan 9.
Air cooled by the evaporator 7 is introduced into the freezing chamber 1 by the turbofan 9, and then is circulated, thereby cooling foodstuffs stored in the freezing chamber 1 and the refrigerating chamber 2.
Even if the turbofan 9 maintains an inner temperature of the refrigerater, it causes noise.
Accordingly, it is required to design the turbofan 9 so as to reduce noise and power consumption and to improve a blowing efficiency for cool air.

DISCLOSURE OF THE INVENTION

Therefore, it is an object of the present invention to provide a turbofan for blowing capable of improving a blowing efficiency for cool air and minimizing power consumption and noise, and a refrigerator having the same.
To achieve these objects, there is provided a turbofan for blowing, comprising: a base plate having a hub protruding from a center thereof; a plurality of blades disposed on an outer circumerential surface of the base plate with a constant interval therebetween in a circumferential direction; and a shroud connected to the blades in opposition to the base plate, wherein a height of the blade is 16%˜26% of an outer diameter of the fan, in which the height of the blade denotes a gap between the base plate and the shroud, and the outer diameter of the fan denotes a diameter of a circle that is obtained by connecting outer ends of the respective blades.
An inner diameter of the shroud is 72%˜85% of the outer diameter of the fan.
An inner diameter of the blade is 55%˜62% of the outer diameter of the fan, in which the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.
To achieve these objects, there is also provided a refrigerator having a turbofan for blowing, the turbofan comprising: a base plate having a hub protruding from a center thereof; a plurality of blades disposed on an outer circumerential surface of the base plate with a constant interval therebetween in a circumferential direction; and a shroud connected to the blades in opposition to the base plate, wherein a height of the blade is 16%˜26% of an outer diameter of a fan, in which the height of the blade denotes a gap between the base plate and the shroud, and the outer diameter of the fan denotes a diameter of a circle that is obtained by connecting outer ends of the respective blades.
In the refrigerator according to the present invention, an inner diameter of the shroud is 72%˜85% of the outer diameter of the fan.
In the refrigerator according to the present invention, an inner diameter of the blade is 55%˜62% of the outer diameter of the fan, in which the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a refrigerator in accordance with the conventional art;

FIG. 2 is a sectional view showing a side of the refrigerator in accordance with the conventional art;

FIG. 3 is a perspective view showing a turbofan for blowing according to the present invention;

FIG. 4 is a planar view showing the turbofan for blowing according to the present invention;

FIG. 5 is a lateral view showing a turbofan for blowing according to the present invention;

FIG. 6 is a graph showing power consumption according to a ratio between a height of a blade and an outer diameter of a fan (H/Do);

FIG. 7 is a graph showing noise according to the ratio between a height of a blade and an outer diameter of a fan (H/Do);

FIG. 8 is a graph showing power consumption according to a ratio between an inner diameter of a shroud and an outer diameter of a fan (Ds/Do);

FIG. 9 is a graph showing noise according to the ratio between an inner diameter of a shroud and an outer diameter of a fan (Ds/Do);

FIG. 10 is a graph showing power consumption according to a ratio between an inner diameter of a blade and an outer diameter of a fan (Di/Do);

FIG. 11 is a graph showing noise according to the ratio between an inner diameter of a blade and an outer diameter of a fan (Di/Do);

FIG. 12 is a graph showing power consumption according to an entrance angle of a blade (B1);

FIG. 13 is a graph showing noise according to the entrance angle of a blade (B1);

FIG. 14 is a graph showing power consumption according to an exit angle of a blade (B2);

FIG. 15 is a graph showing noise according to the exit angle of a blade (B2);

FIG. 16 is a graph showing power consumption according to an outer diameter of a fan (Do);

FIG. 17 is a graph showing noise according to an outer diameter of a fan (Do);

FIG. 18 is a graph comparing power consumption according to a fluid amount of the turbofan for blowing according to the present invention with that of the conventional axial flow fan and the conventional turbofan; and

FIG. 19 is a graph comparing noise according to a fluid amount of the turbofan for blowing according to the present invention with that of the convent ional axial flow fan and the conventional turbofan.

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS

Hereinafter, a turbofan for blowing and a refrigerator according to the present invention will be explained in more detail.
As shown in FIGS. 3 to 5, the turbofan for blowing comprises: a base plate 110 of a disc shape having a hub 111 protruding from a center thereof; a plurality of blades 120 disposed on an outer circumerential surface of the base plate 110 with a constant interval therebetween in a circumferential direction, for blowing cool air introduced from the hub 111 in a radial direction; and a shroud 130 connected to the blades 120 in opposition to the base plate.
A circle that is obtained by connecting outer ends of the respective blades 120 in a radial direction corresponds to an outer circumference of the shroud 130, and is more protruding than an outer circumference of the base plate 110. That is, a diameter (Do) of a circle that is obtained by connecting outer ends of the respective blades 120 is equal to an outer diameter of the shroud 130, but is larger than an outer diameter of the base plate 110.
In the turbofan 100 for blowing, cool air introduced to the hub 111 of the base plate 110 moves between the blades 120 thus to be exhausted in a circumferential direction.
The turbofan 100 for blowing is designed with an optimum condition so as to reduce power consumption and noise and to improve a blowing efficiency. Hereinafter, each optimum component of the turbofan 100 for blowing will be explained.
As shown in FIG. 4, a diameter of a circle (I) that is obtained by connecting inner ends of the respective blades 120 in a radial direction is defined as an inner diameter (Di) of the blades 120. A diameter of a circle (O) that is obtained by connecting outer ends of the respective blades 120 in a radial direction is defined as an outer diameter (Do) of a fan. An angle formed between an extension line (E1) from the inner end of the blade 120 and a tangential line (T1) of the circle (I) that is obtained by connecting inner ends of the respective blades 120 is defined as an entrance angle (B1) of the blade. An angle formed between an extension line (E2) from the outer end of the blade 120 and a tangential line (T2) of the circle (O) that is obtained by connecting outer ends of the respective blades 120 is defined as an exit angle (B2) of the blade.
As shown in FIG. 5, a gap between the base plate 110 and the shroud 130 is defined as a height (H) of the blade 120, and a diameter of inside of the shroud 130 to which cool air is introduced is defined as an inner diameter (Ds) of the shroud.
The turbofan for blowing 100 optimized by designing each factor with an optimum condition will be explained.
FIG. 6 is a graph showing power consumption according to a ratio (H/Do) between a height (H) of the blade 120 and an outer diameter (Do) of the fan, and FIG. 7 is a graph showing noise according to the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan. The power consumption and the noise of FIGS. 6 and 7 are represented as a secondary function, respectively.
As shown in FIG. 6, when the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan is approximately 10% or 30%, the power consumption is increased to be more than approximately 4.5 W. However, when the ratio (H/Do) is approximately 16%˜26%, a maximum value of the power consumption is approximately 2.75 W.
More concretely, the power consumption when the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan is approximately 16%˜26% corresponds to approximately 61% of the power consumption when the ratio (H/Do) is approximately 10% or 30%.
As shown in FIG. 7, when the ratio between the height (H) of the blade 120 and the outer diameter (Do) of the fan is approximately 10% or 30%, the noise is increased to be more than approximately 22 dB. However, when the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan is approximately 16%˜26%, the noise is approximately 19.5 dB.
More concretely, the noise when the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan is approximately 16%˜26% corresponds to approximately 86% of the noise when the ratio (H/Do) is approximately 10% or 30%.
Accordingly, an optimum value of the ratio (H/Do) between the height (H) of the blade 120 and the outer diameter (Do) of the fan is determined as approximately 16%˜26%.
FIG. 8 is a graph showing power consumption according to a ratio between an inner diameter of a shroud and an outer diameter of a fan (Ds/Do), and FIG. 9 is a graph showing noise according to the ratio between an inner diameter of a shroud and an outer diameter of a fan (Ds/Do).
The power consumption and the noise of FIGS. 8 and 9 are represented as a secondary function, respectively.
As shown in FIG. 8, when the ratio (Ds/Do) between an inner diameter (Ds) of the shroud and the outer diameter (Do) of the fan is less than approximately 60% or more than approximately 93%, the power consumption is increased to be more than approximately 3.8 W. However, when the ratio (Ds/Do) is approximately 72%˜85%, a maximum value of the power consumption is approximately 3.25 W.
More concretely, the power consumption when the ratio (Ds/Do) between the inner diameter (Ds) of the shroud and the outer diameter (Do) of the fan is approximately 72%˜85% corresponds to approximately 85% of the power consumption when the ratio (Ds/Do) is approximately 60% or 93%.
As shown in FIG. 9 when the ratio (Ds/Do) between the inner diameter (Ds) of the shroud and the outer diameter (Do) of the fan is less than approximately 65%, the noise is more than 19.8 dB. Also, when the ratio (Ds/Do) is approximately 92.5%, the noise is more than 19.55 dB. However, when the ratio (Ds/Do) is approximately 72%˜87%, a maximum value of the noise is approximately 19.2 dB.
More concretely, the noise when the ratio (Ds/Do) between the inner diameter (Ds) of the shroud and the outer diameter (Do) of the fan is approximately 72%˜87% corresponds to approximately 96% of the noise when the ratio (Ds/Do) is approximately 65% or 92.5%.
Accordingly, an optimum value of the ratio (Ds/Do) between the inner diameter (Ds) of the shroud and the outer diameter (Do) of the fan is determined as approximately 72%˜85%.
FIG. 10 is a graph showing power consumption according to a ratio between an inner diameter of a blade and an outer diameter of a fan (Di/Do), and FIG. 11 is a graph showing noise according to the ratio between an inner diameter of a blade and an outer diameter of a fan (Di/Do).
The power consumption and the noise of FIGS. 10 and 11 are represented as a secondary function, respectively.
As shown in FIG. 10, when the ratio (Di/Do) between the inner diameter (Di) of the blade and the outer diameter (Do) of the fan is approximately 50%, the power consumption is approximately 3.65 W. Also, when the ratio (Di/Do) is approximately 54%˜62%, a maximum value of the power consumption is approximately 3.3 W and a minimum value of the power consumption is approximately 3.25 W.
More concretely, the power consumption when the ratio (Di/Do) between the inner diameter (Di) of the blade and the outer diameter (Do) of the fan is approximately 54%˜62% corresponds to approximately 90% of the power consumption when the ratio (Di/Do) is approximately 50% or 65%.
As shown in FIG. 11, when the ratio (Di/Do) between the inner diameter (Di) of the blade 120 and the outer diameter (Do) of the fan is approximately 50%, the noise is approximately 20.4 dB. Also, when the ratio (Di/Do) is more than approximately 67%, the noise is approximately 20 dB. However, when the ratio (Di/Do) is approximately 55%˜64%, a maximum value of the noise is approximately 19.8 dB and a minimum value of the noise is approximately 19.6 dB.
More concretely, the power consumption when the ratio (Di/Do) between the inner diameter (Di) of the blade and the outer diameter (Do) of the fan is approximately 55%˜64% corresponds to approximately 97% of the power consumption when the ratio (Di/Do) is approximately 50% or 67%.
Accordingly, an optimum value of the ratio (Di/Do) between the inner diameter (Di) of the blade 120 and the outer diameter (Do) of the fan is determined as approximately 55%˜62%.
FIG. 12 is a graph showing power consumption according to an entrance angle of a blade (B1), and FIG. 13 is a graph showing noise according to the entrance angle of a blade (B1).
The power consumption and the noise of FIGS. 12 and 13 are represented as a secondary function, respectively.
As shown in FIG. 12, when the entrance angle (B1) of the blade 120 is approximately 27°˜35°, the power consumption has a low value of approximately 3.35 W. Also, when the entrance angle (B1) of the blade is approximately 32°, the power consumption has a minimum value. When the entrance angle (B1) of the blade 120 is approximately 40°, the power consumption is approximately 3.5 W.
More concretely, the power consumption when the entrance (B1) of the blade 120 is approximately 27°˜35° corresponds to approximately 95% of the power consumption when the entrance (B1) of the blade 120 is less than approximately 25° or more than approximately 40°.
As shown in FIG. 13, when the entrance angle (B1) of the blade 120 is approximately 28°˜37°, the noise has a low value of approximately 18.7 dB. AI so, when the entrance angle (B1) of the blade is approximately 33°, the noise has a minimum value. When the entrance angle (B1) of the blade 120 is approximately 24°, the noise is approximately 19.8 dB.
More concretely, the noise when the entrance (B1) of the blade 120 is approximately 28°˜37° corresponds to approximately 94% of the noise when the entrance (B1) of the blade 120 is less than approximately 24°.
Accordingly, an optimum value of the entrance angle (B1) of the blade 120 is determined as approximately 28°˜35°.
FIG. 14 is a graph showing power consumption according to an exit angle of a blade (B2), and FIG. 15 is a graph showing noise according to the exit angle of a blade (B2).
The power consumption and the noise of FIGS. 14 and 15 are represented as a secondary function, respectively.
As shown in FIG. 14, when the exit angle (B2) of the blade 120 is approximately 31°˜40°, the power consumption has a low value of approximately 3.32 W. Also, when the exit angle (B2) of the blade is approximately 34°, the noise has a minimum value. When the exit angle (B2) of the blade 120 is approximately 22°, the noise is approximately 3.52 W.
More concretely, the power consumption when the exit angle (B2) of the blade 120 is approximately 31°˜40° corresponds to approximately 94% of the power consumption when the exit angle (B2) of the blade 120 is approximately 22°.
As shown in FIG. 15, when the exit angle (B2) of the blade 120 is approximately 30°˜41°, the noise has a low value of approximately 18.75 dB. Also, when the exit angle (B2) of the blade is approximately 34°, the noise has a minimum value of approximately 18.7 dB. When the exit angle (B2) of the blade 120 is approximately 48°, the noise is approximately 19.1 dB.
More concretely, the noise when the exit angle (B2) of the blade 120 is approximately 30°˜41° corresponds to approximately 98% of the noise when the exit angle (B2) of the blade 120 is approximately 48°.
Accordingly, an optimum value of the exit angle (B2) of the blade 120 is determined as approximately 31°˜40°.
FIG. 16 is a graph showing power consumption according to an outer diameter of a fan (Do), and FIG. 17 is a graph showing noise according to an outer diameter of a fan (Do).
The power consumption and the noise of FIGS. 16 and 17 are represented as a secondary function, respectively.
As shown in FIG. 16, when the outer diameter (Do) of the fan is approximately 122 mm˜155 mm, the power consumption has a maximum value of approximately 2.4 W. When the outer diameter (Do) of the fan is approximately 135 mm, the power consumption has a minimum value of approximately 2.2 W. When the outer diameter (Do) of the fan is approximately 110 mm, the power consumption is approximately 2.9 W.
More concretely, the power consumption when the outer diameter (Do) of the fan is approximately 122 mm˜155 mm corresponds to approximately 83% of the power consumption when the outer diameter (Do) of the fan is approximately 110 mm.
As shown in FIG. 17, when the outer diameter (Do) of the fan is approximately 130 mm˜170 mm, the noise has a maximum value of approximately 21 dB. When the outer diameter (Do) of the fan is approximately 155 mm, the noise has a minimum value of approximately 19 dB. When the outer diameter (Do) of the fan is approximately 110 mm, the noise is approximately 25 dB.
More concretely, the noise when the outer diameter (Do) of the fan is approximately 130 mm˜170 mm corresponds to approximately 84% of the noise when the outer diameter (Do) of the fan is approximately 110 mm.
Accordingly, an optimum value of the outer diameter (Do) of the fan is determined as approximately 130 mm˜155 mm.
Referring to FIGS. 18 and 19, a function of the turbofan for blowing 100 according to the present invention will be compared with that of the conventional axial flow fan and the conventional turbofan.
FIG. 18 is a graph comparing power consumption according to a fluid amount of the turbofan for blowing according to the present invention with that of the conventional axial flow fan and the conventional turbofan, and FIG. 19 is a graph comparing noise according to a fluid amount of the turbofan for blowing according to the present invention with that of the conventional axial flow fan and the conventional turbofan.
The outer diameter (Do) of the fan is set to be 140 mm, and the rest factors are set to have a medium value in the aforementioned optimum range, respectively. That is, the height (H) of the blade 120 is 29 mm {140*(0.16+0.26)/ 2}, the inner diameter (Ds) of the shroud 130 is 110 mm, the inner diameter (Di) of the blade 120 is 82 mm, the entrance angle (B1) of the blade 120 is 31.5°, and the exit angle (B2) of the blade 120 is 35.5°.
As shown in FIG. 18, the turbofan for blowing 100 according to the present invention, the conventional turbofan, and the conventional axial flow fan show each increasing function in which the power consumption is increased as the fluid amount is increased.
The turbofan for blowing 100 according to the present invention has less power consumption than the conventional axial flow fan and the conventional turbofan, and shows the smallest gradient.
More concretely, when the fluid amount is increased to 1.5 m³/s from 1.3 m³/s, the conventional axial flow fan has a gradient of 10{(5.4-3.4)/0.2} by in creasing the power consumption to 5.4 W from 3.4 W. In the same condition, the conventional turbofan has a gradient of 9 by increasing the power consumption to 4.6 W from 2.8 W. However, in the same condition, the turbofan for blowing according to the present invention has a gradient of 5 by increasing the power consumption 2.9 W from 1.9 W.
In conclusion, the turbofan for blowing 100 according to the present invention has a smaller power consumption and a smaller gradient than the conventional axial flow fan and the conventional turbofan, thereby having an excellent economical characteristic.
As shown in FIG. 19, the turbofan for blowing 100 according to the present invention, the conventional turbofan, and the conventional axial flow fan show each increasing function in which the noise is increased as the fluid amount is increased.
The turbofan for blowing 100 according to the present invention has less noise than the conventional axial flow fan and the conventional turbofan, and shows the smallest gradient.
In conclusion, the turbofan for blowing 100 according to the present invention has smaller noise and a smaller gradient than the conventional axial flow fan and the conventional turbofan, thereby having a low noise characteristic.
According to another aspect of the present invention, there is provided a refrigerator installed at a rear surface of a grill of a freezing chamber and having the turbofan for blowing cool air generated from an evaporator into the freezing chamber. As the turbofan, an optimized turbofan capable of reducing power consumption and noise is used. The grill of the freezing chamber and the evaporator (not shown) can be easily understood with reference to FIG. 2.
In the present invention, each component of the turbofan for blowing is designed with an optimum state. Accordingly, power consumption is lowered thus to enhance a cooling efficiency and to reduce noise.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A turbofan for blowing, comprising:

a base plate having a hub protruding from a center thereof;

a plurality of blades disposed on an outer circumerential surface of the base plate with a constant interval therebetween in a circumferential direction; and

a shroud connected to the blades in opposition to the base plate,

wherein a height of the blade is 16%˜26% of an outer diameter of a fan, in which the height of the blade denotes a gap between the base plate and the shroud, and the outer diameter of the fan denotes a diameter of a circle that is obtained by connecting outer ends of the respective blades.

2. The turbofan for blowing of claim 1, wherein an entrance angle of the blade is 28°˜35°, in which the entrance angle of the blade denotes an angle formed between an extension line from an inner end of the blade and a tangential line of a circle that is obtained by connecting inner ends of the respective blades.

3. The turbofan for blowing of claim 1, wherein an exit angle of the blade is 31°˜40°, in which the exit angle of the blade denotes an angle formed between an extension line from an outer end of the blade and a tangential line of a circle that is obtained by connecting outer ends of the respective blades.

4. The turbofan for blowing of claim 1, wherein an outer diameter of the fan is in a range of 130 mm˜155 mm.

5. The turbofan for blowing of claim 1, wherein the outer diameter of the fan is equal to that of the shroud, but is larger than that of the base plate.

6. The turbofan for blowing of claim 1, wherein an inner diameter of the shroud is 72%˜85% of the outer diameter of the fan.

7. The turbofan for blowing of claim 1, wherein an inner diameter of the blade is 55%˜62% of the outer diameter of the fan, in which the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.

8. A turbofan for blowing, comprising:

a base plate having a hub protruding from a center thereof;

a shroud connected to the blades in opposition to the base plate,

wherein an inner diameter of the shroud is 72%˜85% of an outer diameter of a fan, in which the outer diameter of the fan denotes a diameter of a circle that is obtained by connects outer ends of the respective blades.

9. The turbofan for blowing of claim 8, wherein an entrance angle of the blade is 28°˜35°, in which the entrance angle of the blade denotes an angle formed between an extension line from an inner end of the blade and a tangential line of a circle that is obtained by connecting inner ends of the respective blades.

10. The turbofan for blowing of claim 8, wherein an exit angle of the blade is 31°˜40°, in which the exit angle of the blade denotes an angle formed between an extension line from an outer end of the blade and a tangential line of a circle that is obtained by connecting outer ends of the respective blades

11. The turbofan for blowing of claim 8, wherein an outer diameter of the fan is in a range of 130 mm˜155 mm.

12. The turbofan for blowing of claim 8, wherein an inner diameter of the blade is 55%˜62% of the outer diameter of the fan, in which the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.

13. A turbofan for blowing, comprising:

a base plate having a hub protruding from a center thereof;

a shroud connected to the blades in opposition to the base plate;

wherein an inner diameter of the blade is 55%˜62% of an outer diameter of a fan, in which the outer diameter of the fan denotes a diameter of a circle that is obtained by connecting outer ends of the respective blades, and the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.

14. The turbofan for blowing of claim 13, wherein an entrance angle of the blade is 28°˜35°, in which the entrance angle of the blade denotes an angle formed between an extension line from an inner end of the blade and a tangential line of a circle that is obtained by connecting inner ends of the respective blades.

15. The turbofan for blowing of claim 13, wherein an exit angle of the blade is 31°˜40°, in which the exit angle denotes an angle formed between an extension line from an outer end of the blade and a tangential line of a circle that is obtained by connecting outer ends of the respective blades.

16. The turbofan for blowing of claim 13, wherein an outer diameter of the fan is in a range of 130 mm˜155 mm.

17. The turbofan for blowing of claim 13, wherein a height of the blade is 16%˜26% of the outer diameter of the fan, in which the height of the blade denotes a gap between the base plate and the shroud.

18. A refrigerator having a turbofan for blowing, the turbofan comprising:

a base plate having a hub protruding from a center thereof;

a shroud connected to the blades in opposite to the hub,

19. The refrigerator of claim 18, wherein an inner diameter of the shroud is 72%˜85% of the outer diameter of the fan.

20. The refrigerator of claim 18, wherein an inner diameter of the blade is 55%˜62% of the outer diameter of the fan, in which the inner diameter of the blade denotes a diameter of a circle that is obtained by connecting inner ends of the respective blades.