TURBO FAN FOR BLOWING AND REFRIGERATOR HAVING THE SAME

TECHNICAL FIELD

The present invention relates to a turbofan for blowing and a refrigerat or having the same, and more particularly, to a turbofan for blowing capable o f improving a blowing efficiency for cool air and minimizing power consumptio n and noise, and a refrigerator having the same.

BACKGROUND ART In general, a refrigerator serves to store foodstuffs as a freezing state o r 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 disp osed at a front surface of the body 10 for opening and closing the freezing ch amber 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 b ody 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 refrigerato r, it causes noise. Accordingly, it is required to design the turbofan 9 so as to reduce nois

e 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 f or blowing capable of improving a blowing efficiency for cool air and minimizin g power consumption and noise, and a refrigerator having the same.

To achieve these objects, there is provided a turbofan for blowing, com prising: 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 c onnected 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 di ameter 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 t he fan.

An inner diameter of the blade is 55%~62% of the outer diameter of th e fan, in which the inner diameter of the blade denotes a diameter of a circle t hat 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 protr uding from a center thereof; a plurality of blades disposed on an outer circum erential surface of the base plate with a constant interval therebetween in a ci rcumferential 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 diamete r of a fan, in which the height of the blade denotes a gap between the base pi ate 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 conne cting inner ends of the respective blades.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a refrigerator in accordance with t he conventional art; FIG. 2 is a sectional view showing a side of the refrigerator in accordan ce with the conventional art;

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

FIG. 4 is a planar view showing the turbofan for blowing according to th e 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 bet ween 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 heigh

t of a blade and an outer diameter of a fan (H/Do);

FIG. 8 is a graph showing power consumption according to a ratio bet ween 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 inne r 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 bet ween 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 inn er diameter of a blade and an outer diameter of a fan (Di/Do); FIG. 12 is a graph showing power consumption according to an entran ce 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 an gle 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 d iameter of a fan (Do); FIG. 17 is a graph showing noise according to an outer diameter of a f an (Do);

FIG. 18 is a graph comparing power consumption according to a fluid a mount 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 t

urbofan 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 p resent invention will be explained in more detail.

As shown in FIGS. 3 to 5, the turbofan for blowing comprises: a base p late 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 bas e 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 s hroud 130 connected to the blades 120 in opposition to the base plate.

A circle that is obtained by connecting outer ends of the respective bla des 120 in a radial direction corresponds to an outer circumference of the shr oud 130, and is more protruding than an outer circumference of the base plat e 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 th e base plate 110 moves between the blades 120 thus to be exhausted in a cir cumferential 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 efficien cy. 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 connec ting 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 obta ined by connecting outer ends of the respective blades 120 in a radial directio n 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 forme d between an extension line (E2) from the outer end of the blade 120 and a ta ngential 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 th e 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 a n optimum condition will be explained.

FIG. 6 is a graph showing power consumption according to a ratio (H/D o) between a height (H) of the blade 120 and an outer diameter (Do) of the fa n, 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 po wer consumption and the noise of FIGS. 6 and 7 are represented as a second ary function, respectively.

As shown in FIG. 6, when the ratio (H/Do) between the height (H) of th e blade 120 and the outer diameter (Do) of the fan is approximately 10% or 3

0%, the power consumption is increased to be more than approximately 4.5W . However, when the ratio (H/Do) is approximately 16%~26%, a maximum val ue of the power consumption is approximately 2.75W.

More concretely, the power consumption when the ratio (H/Do) betwee n the height (H) of the blade 120 and the outer diameter (Do) of the fan is app roximately 16%~26% corresponds to approximately 61% of the power consu mption 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 22dB. However, when the r atio (H/Do) between the height (H) of the blade 120 and the outer diameter (D o) of the fan is approximately 16%~26%, the noise is approximately 19.5dB.

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 a pproximately 16%~26%. FIG. 8 is a graph showing power consumption according to a ratio bet ween an inner diameter of a shroud and an outer diameter of a fan (Ds/Do), a nd FIG. 9 is a graph showing noise according to the ratio between an inner di ameter of a shroud and an outer diameter of a fan (Ds/Do).

The power consumption and the noise of FIGS. 8 and 9 are represente d 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 approxi mately 60% or more than approximately 93%, the power consumption is incre ased to be more than approximately 3.8W. However, when the ratio (Ds/Do) i s approximately 72%~85%, a maximum value of the power consumption is ap proximately 3.25W.

More concretely, the power consumption when the ratio (Ds/Do) betwe en the inner diameter (Ds) of the shroud and the outer diameter (Do) of the fa n 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 approxi mately 65%, the noise is more than 19.8dB. Also, when the ratio (Ds/Do) is a pproximately 92.5%, the noise is more than 19.55dB. However, when the rati o (Ds/Do) is approximately 72%~87%, a maximum value of the noise is appro ximately 19.2dB.

More concretely, the noise when the ratio (Ds/Do) between the inner di ameter (Ds) of the shroud and the outer diameter (Do) of the fan is approxima tely 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 d iameter (Ds) of the shroud and the outer diameter (Do) of the fan is determine d as approximately 72%~85%.

FIG. 10 is a graph showing power consumption according to a ratio bet ween 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 dia meter of a blade and an outer diameter of a fan (Di/Do).

The power consumption and the noise of FIGS. 10 and 11 are represe nted as a secondary function, respectively. As shown in FIG. 10, when the ratio (Di/Do) between the inner diamete r (Di) of the blade and the outer diameter (Do) of the fan is approximately 50

%, the power consumption is approximately 3.65W. Also, when the ratio (Di/D o) is approximately 54%~62%, a maximum value of the power consumption is approximately 3.3W and a minimum value of the power consumption is appr oximately 3.25W.

More concretely, the power consumption when the ratio (Di/Do) betwe en the inner diameter (Di) of the blade and the outer diameter (Do) of the fan i s approximately 54%~62% corresponds to approximately 90% of the power c onsumption when the ratio (Di/Do) is approximately 50% or 65%. As shown in FIG. 11 , when the ratio (Di/Do) between the inner diamete r (Di) of the blade 120 and the outer diameter (Do) of the fan is approximately

50%, the noise is approximately 20.4dB. Also, when the ratio (Di/Do) is more t han approximately 67%, the noise is approximately 2OdB. However, when the ratio (Di/Do) is approximately 55%~64%, a maximum value of the noise is a pproximately 19.8dB and a minimum value of the noise is approximately 19.6 dB.

More concretely, the power consumption when the ratio (Di/Do) betwe en the inner diameter (Di) of the blade and the outer diameter (Do) of the fan i s approximately 55%~64% corresponds to approximately 97% of the power c onsumption when the ratio (Di/Do) is approximately 50% or 67%.

Accordingly, an optimum value of the ratio (Di/Do) between the inner di ameter (Di) of the blade 120 and the outer diameter (Do) of the fan is determi ned as approximately 55%~62%.

FIG. 12 is a graph showing power consumption according to an entran ce angle of a blade (B1), and FIG. 13 is a graph showing noise according to t he entrance angle of a blade (B1 ).

The power consumption and the noise of FIGS. 12 and 13 are represe nted 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 approxima tely 3.35W. 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 approxi mately 3.5W. More concretely, the power consumption when the entrance (B 1 ) 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 ap proximately 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 18.7dB. Al 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 appr oximately 24°, the noise is approximately 19.8dB.

More concretely, the noise when the entrance (B1) of the blade 120 is approximately 28°~37°corresponds to approximately 94% of the noise when t

he 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 an gle of a blade (B2), and FIG. 15 is a graph showing noise according to the exi t angle of a blade (B2).

The power consumption and the noise of FIGS. 14 and 15 are represe nted as a secondary function, respectively.

As shown in FIG. 14, when the exit angle (B2) of the blade 120 is appr oximately 31°~40°, the power consumption has a low value of approximately

3.32W. Also, when the exit angle (B2) of the blade is approximately 34°, the n oise has a minimum value. When the exit angle (B2) of the blade 120 is appro ximately 22°, the noise is approximately 3.52W.

More concretely, the power consumption when the exit angle (B2) of th e blade 120 is approximately 31°~40°corresponds to approximately 94% of th e power consumption when the exit angle (B2) of the blade 120 is approximat ely 22°.

As shown in FIG. 15, when the exit angle (B2) of the blade 120 is appr oximately 30°~41 °, the noise has a low value of approximately 18.75dB. Also, when the exit angle (B2) of the blade is approximately 34°, the noise has a minimum value of approximately 18.7dB. When the exit angle (B2) of the blad e 120 is approximately 48°, the noise is approximately 19.1dB.

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 i s determined as approximately 31°~40°.

FIG. 16 is a graph showing power consumption according to an outer d iameter of a fan (Do), and FIG. 17 is a graph showing noise according to an o uter diameter of a fan (Do).

The power consumption and the noise of FIGS. 16 and 17 are represe nted as a secondary function, respectively.

As shown in FIG.16, when the outer diameter (Do) of the fan is approxi mately 122mm~155mm, the power consumption has a maximum value of app roximately 2.4W. When the outer diameter (Do) of the fan is approximately 13 5mm, the power consumption has a minimum value of approximately 2.2W. When the outer diameter (Do) of the fan is approximately 110mm, the power consumption is approximately 2.9W.

More concretely, the power consumption when the outer diameter (Do) of the fan is approximately 122mm~155mm corresponds to approximately 8 3% of the power consumption when the outer diameter (Do) of the fan is appr oximately 110mm.

As shown in FIG. 17, when the outer diameter (Do) of the fan is approx imately 130mm~170mm, the noise has a maximum value of approximately 21 dB. When the outer diameter (Do) of the fan is approximately 155mm, the noi se has a minimum value of approximately 19dB. When the outer diameter (Do

) of the fan is approximately 110mm, the noise is approximately 25dB.

More concretely, the noise when the outer diameter (Do) of the fan is a pproximately 130mm~170mm corresponds to approximately 84% of the noise when the outer diameter (Do) of the fan is approximately 110mm.

Accordingly, an optimum value of the outer diameter (Do) of the fan is determined as approximately 130mm~155mm.

Referring to FIGS. 18 and 19, a function of the turbofan for blowing 10 0 according to the present invention will be compared with that of the conventi onal axial flow fan and the conventional turbofan.

FIG. 18 is a graph comparing power consumption according to a fluid a mount 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 i s a graph comparing noise according to a fluid amount of the turbofan for bio wing 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 140mm, and the rest fac tors are set to have a medium value in the aforementioned optimum range, re spectively. That is, the height (H) of the blade 120 is 29mm {140*(0.16+0.26)/ 2}, the inner diameter (Ds) of the shroud 130 is 110mm, the inner diameter (D i) of the blade 120 is 82mm, 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 pre sent invention, the conventional turbofan, and the conventional axial flow fan show each increasing function in which the power consumption is increased a s the fluid amount is increased.

The turbofan for blowing 100 according to the present invention has les s power consumption than the conventional axial flow fan and the convention al turbofan, and shows the smallest gradient. More concretely, when the fluid amount is increased to 1.5m ³ /s from 1.

3m ³ /s, the conventional axial flow fan has a gradient of 10{(5.4-3.4)/0.2} by in creasing the power consumption to 5.4W from 3.4W. In the same condition, th e conventional turbofan has a gradient of 9 by increasing the power consumpt ion to 4.6W from 2.8W. However, in the same condition, the turbofan for blowi ng according to the present invention has a gradient of 5 by increasing the po wer consumption 2.9W from 1.9W.

In conclusion, the turbofan for blowing 100 according to the present inv ention has a smaller power consumption and a smaller gradient than the conv entional axial flow fan and the conventional turbofan, thereby having an excell ent economical characteristic.

As shown in FIG. 19, the turbofan for blowing 100 according to the pre sent invention, the conventional turbofan, and the conventional axial flow fan show each increasing function in which the noise is increased as the fluid am ount is increased. The turbofan for blowing 100 according to the present invention has les s noise than the conventional axial flow fan and the conventional turbofan, an d shows the smallest gradient.

In conclusion, the turbofan for blowing 100 according to the present inv ention has smaller noise and a smaller gradient than the conventional axial flo w 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 ha ving the turbofan for blowing cool air generated from an evaporator into the fr eezing chamber. As the turbofan, an optimized turbofan capable of reducing p

ower consumption and noise is used. The grill of the freezing chamber and th e 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 t hus to enhance a cooling efficiency and to reduce noise.

It will be apparent to those skilled in the art that various modifications a nd 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.