GB2372785A - Three-bladed axial flow fan for the condenser of a refrigerator - Google Patents

Abstract

A quieter axial flow fan for the condenser of a refrigerator has three blades. In one claim, the diameter d of the hub is 23.3Ò5% of the outside diameter D of the fan and the width b of each blade is 36.6Ò3% of D. In another claim, the diameter d of the hub is 23.0Ò5% of D, the maximum camber position is 0.65 uniformly distributed from the hub to the tip and the maximum camber has curved distributions of 4.0% to 5.0% from the hub to the maximum camber position and of 5.0% to 6.0% from the maximum camber position to the tip.

Description

FAN FOR CONDENSER OF REFRIGERATOR

The present invention relates to a refrigerator, and more particularly, to an axial

flow fan for a condenser for reducing flotnoise in a refrigerator.

In general, a refrigerator in use for freezing or cooling foods includes a housing for defining receiver spaces therein divided into freezer and refrigerator compartments, upper and lower doors installed in one side of the housing for opening/shutting the freezer and refrigerator compartments and instruments which include a compressor, a condenser and an evaporator for carrying out a cooling cycle for cooling the freezer and refrigerator compartments.

In such a refrigerator, a gaseous refrigerant in low temperature and pressure is compressed to have a high temperature and pressure by a compressor. The compressed hot and high-pressure gaseous refrigerant is cold compressed to a high-pressure liquid while passing through a condenser. The high-pressure refrigerant is lowered in temperature and pressure while passing through capillaries, and consequently absorbs heat from the surrounding to cool the neighboring air in the evaporator while being converted to a gas having a low temperature and pressure. The cold air cooled via the evaporator is circulated into the freezer and refrigerator compartments through the operation of a blower fan so that the freezer and refrigerator compartments are lowered m temperature.

In a refrigerator as shown in Fig. 1, a condenser 10 and a compressor 12 are installed in a so-called machine space or compartment in the outer bottom of a housing, and a blower fan assembly is arranged in one side thereof for absorbing the outer air into the machine room and flowing the same toward the condenser 10 to effectively cool a refrigerant introduced into the condenser 10.

The blower fan assembly is comprised of an axial flow fan 20 and a motor 22 for driving the axial flow fan 20, in which the axial flow fan 20, as shown in Fig. 2, is constituted by a hub 201 connected to the rotation axis of the motor 22 and a number of blades 202 arranged in the outer periphery of the hub 201.

According to the blower fan assembly, the axial flow fan 20 is rotated through operation of the motor 22 to cause the pressure difference between the front and rear surfaces of the blades 202. This pressure difference causes the outer air to flow into the machine space and then toward the condenser 10.

Examples of characteristic factors for determining the blowing characteristics of such an axial flow fan 20 include a sweep angle, the maximum camber amount, the number of the blades 202 and the like. The sweep angle, as shown in Fig. 2, means an angle a defined by the Y axis and a line passing the center of the inner side of the blade 202 and the center of the hub 201, in which the Y axis is a line that connects between the center of the inner side of the blade 202 or the center of a portion of the blade contacting with the hub 201 and the center of the outer side or tip of the blade.

Also, as shown in Fig. 2B, the maximum camber amount p means the straight length between a chord connecting the leading edge L. E. and a trailing edge T. E. of the blade 202 and the maximum camber position P.

In this case. the sweep angle a is a factor for determining flow noise of the axial ilow fan 20. a large value of the sweep angle a increases the phase difference of

airflow between the hub 201 and the tip of the blade 202 whereas a small amount of sweep angle a decreases the phase difference of the airflow.

For example, comparing two axial flow fans with the same blade number and blowing amount, a blade with a sweep angle of 30 , as shown in Fig. 3A, allows an airflow to pass through the blade during rotation thereof for about 230 whereas a blade with a sweep angle of 60 , as shown in Fig. 3B, allows an airflow to pass through the blade during rotation thereof for about 49 .

In other words, according to the sweep angle a, the airflow passing the outer end or tip of the blade has the phase difference of 230 and the airflow passing the inner end of the blade has the phase difference of 49 .

Therefore, such a phase difference of the airflow causes a phase difference between noises from the outer end of the blade 202 and from the inner end thereof, in which the frequency passing through the blade decreases as the phase difference is larger.

The maximum camber amount p is a factor for determining the pressure difference between the upper and lower surfaces of the blade 202, in which increment of the maximum camber amount p increases the pressure difference between the upper and lower surfaces thereby increasing the blade-passing frequency also.

Meanwhile, according to the structure of the machine room with a simple passage and a small value of passage resistance, it is efficient that the axial flow fan 20 is configured to have a low level of noise even if a blowing pressure is more or less low rather than the blowing pressure is high. However, the axial flow fan 20 applied to a conventional blower fan assembly has a configuration in which a space between the blades 202 is narrow and the sweep angle a is small whereas the camber amount is large and the number of the blades 202 is three.

Since the narrow space between the blades 202 resultantly causes the blades 202 to be large sized, the airflow generated on the surface of the blades 202 may have a large peeling range and a large pressure-fluctuating range, which are reasons for increasing flow noise. Further, the sweep angle a is small and the maximum camber amount p is large so that flow noise is increased due to the foregoing characteristics of the sweep angle and the maximum camber amount.

Therefore, the axial fan for condenser in the refrigerator of the related art has loud flow noise thereby degrading the performance of the refrigerator as a problem.

It is accordingly an object of the invention to seek to mitigate these disadvantages of the prior art.

According to a first aspect of the invention there is provided an axial flow fan for a condenser in a refrigerator, the axial flow fan comprising three blades,

wherein the diameter of a hub is 23. 35% of the outside diameter of the axial flow fan and the width of each of the blades is 36. 63% of the outside diameter of the axial flow fan.

According to a second aspect of the invention there is provided an axial flow fan for condenser in a refrigerator, the axial flow fan comprising three blades, wherein the ratio of the inside diameter to the outside diameter is 23. 0t5%, the maximum camber position is 0.65 uniformly distributed from the hub to the tip, and the maximum camber has curved distributions of 4.0 to 5.0% from the hub to the maximum camber position and of 5.0 to 6. 0% from the maximum camber position to the tip.

Fig. 1 is a perspective view for showing the structure of a machine room of a general refrigerator; Figs. 2an and 2B are plan and side elevation views for showing characteristic factors of an axial flow fan constituting a general blower fan assembly; Figs. an and 3B are graphs for showing the phase difference of airflows according to sweep angles of characteristic factors of axial flow fans;

Figs. 4an and 4B are plan and side elevation views for showing characteristic ZD factors of an axial flow fan for condenser according to the invention; Fig. 5 is a graph for showing noise variation according to the number of blades of characteristic factors of an axial flow fan according to the invention; Fig. 6 is a graph for showing noise variation according to blade widths of characteristic factors of an axial flow fan according to the invention; Fig. 7 is a graph for showing noise spectra of axial flow fans of the invention and the related art; Fig. 8 is a graph for showing noise variation of an axial flow fan according to variation of pitch angle of the invention; Fig. 9 is a graph for showing noise variation of an axial flow fan according to variation of sweep angles of the invention; Fig. 10 is a sectional view for an axial flow fan for a refrigerator of the invention in which the boundary of a blade is divided into 160 areas for illustration.

Fig. 11 is a graph for comparing noise variation of an axial flow fan of the invention with that of the related art.

Hereinafter detailed description will be made about the invention in reference to the accomoanvins drawings as follows.

As shown there is provided an axial flow fan for condenser in a refrigerator, characterized in that the number of blades is three, the diameter of a hub is 23. 3 5% of the outside diameter of the axial flow fan and the width of each of the blades is 36. 6~3% of the outside diameter of the axial flow fan.

The axial flow fan of the invention is characterized in that the outside diameter of the axial flow fan is 150~1mm. the diameter of the hub is 35lamm, and the width of the blade is 55+1mm.

Also, the axial flow fan of the invention is characterized in that each blade has the maximum camber position of 0.65 which is uniformly distributed from the hub to the tip, wherein the maximum camber has curved distributions of 4.0 to 5.0% from the hub to the maximum camber position and of 5.0 to 6.0% from the maximum camber

position to the tip, each blade having a pitch angle of 36. 0 to 26. 00from the hub to the tip defining a linear distribution, and a sweep angle ouf 67. 0'5%.

Hereinafter, detailed description will be made about the first embodiment of the invention with reference to Figs. 4 to 7. in which the same reference numerals will be used for the elements an axial flow fan of the invention similar to those of the related art.

First, an axial flow fan for a condenser in a refrigerator according to the first embodiment of the invention is configured to have three blades 202 as shown in Fig. 4A. in which the diameter d of a hub is 23.3~5% of the outside diameter D of the axial flow ran and the width b of each of the blades is 36. 6+3% of the outside diameter D of the axial flow fan as shown in FIg. 4B.

In this case, it is preferable that the outside diameter D of the axial flow fan, the diameter d of the hub and the width b of the blade are respectively sized to satisfy the foregoing ratios such as 150=lmm, 35mm and 55mm considering the volume of a machine room.

Those magnitudes are selected as a result of experiments, which were made to axial flow fans with 3,5, 7 and 9 blades in order to compare flow noise according to the number of blades. As shown in Fig. 5, flow noise has the smallest level in the axial flow fan where the number of the blades is 3 or 7.

Further, comparing the fan with 3 blades to the fan with 7 blades, the fan with 3 blades is more smooth in rate of increment and higher in convenience of manufacture and thus has an enhanced performance and is relatively efficient to manufacture.

The blade width b is also an important factor for determining flow noise in a passage closed in the axial direction of the axial flow fan such as the machine space of the refrigerator, and as shown in Fig. 6, it can be seen that flow noise has the smallest value when the ratio of the blade width b is 36.6% about the outside diameter D of the axial flow fan.

Further, in the first embodiment of the invention, the axial flow fan has a configuration in which the maximum camber position P of the each blade 202 is 0.65 uniformly distributed from the hub 201 to the tip, the maximum camber MC having curved distributions of 4.0 to 5.0% from the hub 201 to the maximum camber position P and of 5.0 to 6.0% from the maximum camber position P to the tip, a pitch angle 13 is 36. 0 to 26. 00from the hub 201 to the tip showing a linear distribution, and a sweep angle a is67. 0 5%.

Therefore. in the tirst embodiment of the invention, the fan has J. rotation velocity increase of about 50rpm and noise decrease of aboUt 2dB as shown in Fig. 7 under the condition that the airflow is the same as the conventional axial flow fan.

According to the blower fan for a condenser in the refrigerator of the invention as described hereinbefore, the flow noise and the blade-passing frequency are reduced due to factors having characteristics such as the number and the maximum camber of the blade and the width rate of the blade about the outside diameter of the axial flow fan so that the refrigerator is advantageously improved in performance.

Hereinafter a detailed description will be given of an axial flow fan for a refrigerator according to the second embodiment of the invention with reference to the accompanying drawings and a table as follows.

As shown in Fig. 5, it can be seen that noise from the axial flow fan is inversely proportional to the number of the blades for the same blowing amount. This means that the increment of the number of the blades is the most important factor for overcoming passage resistance and is the most important factor in increased of noise in blowing.

Therefore, it is perferable with regard to noise to apply an axial flow fan with fewer blades as long as the amount of airflow is not reduced to a great extent.

Fig. 8 is a graph showing noise variation in the axial flow fan according to variation of the pitch angle, which is a result of experiments with an axial flow fan with three blades based upon the result in Fig. 5, in which the vertical axis indicates sound pressure and the horizontal axis indicates pitch angle.

The pitch angles shown in Fig. 8 are values at the tip, in which noise is inversely proportional to increment of the pitch angle and then proportional to increment of the pitch angle when the value of the pitch angle increases beyond a certain range. In this case, the pitch angle ranges 20 to 250 have the lowest level of noise.

Fig. 9 is a graph showing the variation of noise in the axial flow fan

according to the variation of the sweep angle, in which the vertical axis indicates sound pressure and the horizontal axis indicates the sweep angle at the tip.

The sweep angle indicates the degree of inclination of the blade in the rotational direction, which is the angle defined by imaginary lines connecting from the hub to the center of the blade and from the tip to the center of the blade together with a line perpendicular to the rotation angle. The sweep angle for reducing noise of the fan has a value of 0 at the hub and a certain value at the tip according to a function.

As shown in Fig. 9, it can be seen that noise is minimized when the sweep angle is 69 to 72'at the tip.

Description will now be made as follows about the optimal axial flow fan for the refrigerator according to the second embodiment of the invention which can minimize noise based upon variation concerning the foregoing factors such as the number of blades, the pitch angle and the sweep angle.

First, as shown in Figs. 4an and 4B, the axial flow fan 20 for the refrigerator according to the second embodiment of the invention is comprised of the hub 201 coupled to the rotation axis of the motor and the 3 blades 202 radially provided in the outer periphery of the hub for blowing the air through rotation thereof.

Each of the blades 202 is an element for incurring airflows, and the three dimensional contour of the each blade is defined by several factors for determining the flow characteristics of the axial flow fan.

In the second embodiment of the invention, the hub diameter d of the axial flow fan is 23. 0+5% of the outside diameter D of the fan, in which practically the rotational diameter D of the axial flow fan is 110lmm, the hub diameter d is 25 Imm and the blade width b of the axial flow fan is 36. 0 1mm.

In the second embodiment of the invention, the maximum camber

position P of the axial flow fan 20 is 0. 65 uniformly distributed from the hub 21 to the tip, and the maximum camber MC has curved distributions of 4.0 to 5.0% from the hub to the maximum camber position P and of 5.0 to 6.0% from the maximum camber position to the tip.

Also, the pitch angle of the axial flow fan has a linear distribution of 35.0 to 24. 0 from the hub 201 to the tip. In this case, the optimal value is selected as the pitch angle from the range of 20 to 250 where noise is minimized from the result of Fig. 4.

The sweep angle a of the axial flow fan according to the second embodiment of the invention has a value of 72. 0 10% from the tip. This is selected to satisfy the range of 69 to 720 where noise is minimized from the result of Fig. 5. In other words, the sweep angle a the axial flow fan 20 is much larger than the sweep angle of the conventional axial flow fan so that the axial flow fan 20 can minimize interference in flowing with other components located in the rear of the axial flow fan 20 including the condenser thereby reducing noise to a great amount.

The axial flow fan 20 configured as above can have both clockwise and counterclockwise rotation directions.

Meanwhile, boundary data of the blade 202 constituting the axial flow fan will described in reference to the drawings and the table as follows First, Fig. 10 is a sectional view of the axial flow fan for a refrigerator embodying the invention for illustrating the boundary of blade in 160 areas, in which the boundary of the blade 202 is divided into 160 areas and then the position of each area is displayed with three coordinates X, Y and Z to show a three-dimensional configuration.

As shown in Fig. 10. the blade 202 is divided into 160 areas m clockwise

sequence from the hub-side front 1 via the hub-side rear 41, the tip-side rear and the tip-side front 121 to the hub-side front 161 again, in which the coordinates of the each area are as in the following Table. In this case, the X coordinates indicate the horizontal axis, the Y coordinates indicate the vertical axis and the Z coordinates

indicate the rotation axis, in which the boundary value of the each area has a unit of mm.

Table 1

No X Y Z 1-9368 8. 276-6. 559 2-9 341 8 307-6 544 3-9. 261 8. 396 -6.5 4-9. 129 3. 539-6. 426 5-8. 945 8 731-6. 323 6-8. 711 8. 965-6 19 7-8. 423 9336-6. 026 8 - 8. 084 9 534 - 5 831 9-7. 691 9. 854-5. 605 0-7. 245 10. 186-5. 345 1-6. 746 10. 523-5. 053 12 -6.196 10 857 -4 729 13 -5 595 11.178 -4.373 14 -4 948 11 479 -3 988 S-4. 257 11 753-3. 574 6 -3 527 11 992 -3 136 17 -2 763 12. 191-2. 677 8 -1 972 12.343 -2.199 19 -1.16 12.446 -1. 709 20 -0.335 12.496 -1 21 21 0. 495 12.49 -0. 707 22 1 324 12 43 -0.206 23 2. 138 12. 316 0.293 24 2.924 12. 153 0.8 25 3.673 11.948 1.309 26 4. 381 11. 707 1. 817 27 5. 045 11 437 2.318 28 5 662 11. 144 2.809 29 6 23 10.837 3. 284 30 6. 748 10.522 3 742 31 7.216 10.207 4.177 32 7 634 9.898 4. 586 33 8.005 9. 601 4. 966 34 8. 328 9.322 5. 314 35 8. 605 9.066 5. 625 36 8.838 8.839 5.898 37 9.028 8. 645 6. 128 38 9. 176 8. 489 6. 312 39 9. 282 8.372 6. 447 40 9. 346 8. 301 6. 531 41 9.368 8. 276 6. 559 42 9. 192 9.972 6. 643 43 8.952 11.565 6.753 44 8. 671 13.073 S. S9 45 8 368 1451 7. 049 46 8.053 15.888 7.225 47 7 734 17. 218 7412 48 7417 18 506 7 603 49 7 106 19 761 7 789 50 6 804 20.987 7 975 51 6. 512 22. 189 8. 173 52 6 233 23. 371 8 382 53 5.968 24 535 8. 602 54 5 698 25 688 8.823

55 5407 26 836 9035 56 5.095 27 977 9.237 57 4 76 29 114 9 43 5S 4. 402 30. 244 9. 613 59 4.023 31 368 9.786 60 3. 621 32. 486 9.95 61 3.196 33.598 10. 103 62 2. 748 34 704 10. 247 63 2 277 35 803 10.382 64 1. 783 36. 894 10.506 65 1. 266 37 979 10 621 66 0. 726 39.056 10.726 67 0 162 40 125 10 821 eu-0. 426 41. 185 10.906 69-1067 42.237 10.967 70 -1 798 43.275 10.986 71-2 621 44 298 10 963 72-3. 534 45.3 10.9 73 -4. 537 46 278 10. 797 74-5. 63 47. 228 10.656 75 -6.812 48.146 10.477 76-8. 081 49.026 10. 187 77 9437 49 865 9. 688 78 -10.88 50.657 8.893 79 -12.44 51 39 7. 774 80 -15. 35 51.709 5. 006 81 -19 85 51. 295 -1 122 82 -19 96 51. 25-1. 293 83-20 3 51. 116-1. 665 84-20 85 50. 894-2. 224 85-21. 6 50. 58-2. 954 86-22. 54 50. 168 -3.837 87-23. 65 49. 654-4. 854 88 -24 93 49. 028 -5.984 89 -26 34 48. 281-7. 203 90-27. 89 47. 405-8. 485 91-29. 55 46. 389-9. 807 92 -31. 3 45. 225 -11.15 93-33. 13 43. 906-12. 49 94-35 42. 423-13. 8 95-3691 40. 773 -15 07 96-38. 83 38. 953-16. 28 97-40 73 36. 962-17 39 98-42. 59 34. 805 -18. 41 99 -44 38 32. 485-19. 31 00 -46. 09 30. 017 -20 09 01 -47 67 27 442-20 8 02 -49.1 24. 783-2147 103 -50 38 22.064 -22 07 104 -51 5 19.307 -22.61 105 -52 46 16 537 -23 08 106 -53.251 13.7781 -23 49 107 -53 88 11 056 -22 82 108 -54 36 8.395 -24.1 109 -54 69 5 819 -24 31

110 -54 9 3 351 -24 48 111 -54.99 1 012 -24.61 112 -54.99 -1 177 -24 69 113 -54.91 -3 199 -24 74 114 -54 77 -5.036 -24 77 115-S. 59-6. 67S-2 78 116 -54 4 -8.093 -24 78 117 -54.21 -9.285 -24 78 118 -54.04 -10 23 -24 78 119-53. 9-10. 93-4. 8 120 -53.82 -11 36 -24 84 121-53. 78-11. 5-24 89 122 -52 11 -13.91 -24 44 123 -50.88 -14 09 -24 11 124 -50 07 -13.33 -23.9 125 -49.26 -12.22 -23 68 126 -48 43 -11 1 -23 44 127 -47.59 -9.975 -23.18 123-46. 73-a 348-22. 9 129 -45.86 -7.717 -22.6 130 -44 96 -6 581 -22 29 131-44. 04-5. 44-21 95 1 32-43 1-4 294-21 59 133 -42.13 -3 145 -21 2 134 -41.14 -1.991 -20.79 135-40. 12-0. 87-20. 36 136 -39 06 0. 186-19. 91 137 -37. 98 1. 178 -19 45 138-36 88 2 105-1 a 98 139-35 75 2. 967-18 49 140 -34 61 3. 764-1 a 141 -33 45 4. 495 -17 49 142 -32.28 5.161 -16.98 143 -31.1 5.761 -16 46 144 -29. 91 6. 297-1 5. 94 145 28. 71 6. 768-1 5 dol 146 -27.52 7 175 -14.88 147 -26.32 7 518 - 14. 36 148 -25.13 7 799 -13 83 149 -23. 94 8. 017 -13. 31 150 -22.76 8. 191-1278 151-21 57 8. 339-12. 25 1 si-20. 38 8461 11 71 153 -19.18 8. 556 11 16 154 -17 98 8. 623 -10 6 15-16. 77 8 663-10. 04 156 -15.56 8 675 -9 474 157-14. 34 8. 6581 -8 901 158-13. 31 8 611-8 323 159 - 1'86 8. 533 -7.739 160 -10 63 8 422 -7 152 161-9 368 8 276-6. 559

Unit : mm

The axial flow fan according to the second embodiment of the invention is compared to the conventional axial flow fan about the degree of generating noise in the same amount of airflow as follows.

First, Fig. 11 is a graph for illustrating noise variation according to a model of the axial flow fan of the second embodiment of the invention and a conventional axial flow fan, in which the vertical axis indicates sound pressure and the horizontal axis indicates fluidity for comparing the axial flow fans of the invention to the related art according to flow capacities such as 140,420 and 500 liters.

As shown in Fig. 11, for 140 liters, the axial flow fan A2 according to the second embodiment of the invention has a noise level lower than that of the related art Al by about 4.14dB at the same amount of airflow. For 360 liters, the axial flow fan D2 according to the second embodiment of the invention has a noise level lower than that of the related art Dl by about 2.35 dB at the same amount of airflow, for 420 liters, lower by about 2.54 dB (C2, Cl) and for 500 liters lower by about 2.55 dB (D2, Dol).

Therefore, the axial flow fan according to the second embodiment of the invention can reduce at least 2. 5 dB of noise on average compared to the conventional axial flow fan in obtaining the same amount of airflow even if there are some differences according to a particular model.

In this case, rotation of the axial flow fan according to the second embodiment of the invention is smaller by about 100rpm than that of the conventional axial flow fan so that the same amount of airflow can be obtained for a low rotation velocity and thus the efficiency of the axial flow fan can be enhanced.

Claims (10)

CLAIMS :

1. An axial flow fan for a condenser in a refrigerator, the axial flow fan comprising three blades, wherein the diameter of a hub is 23. 3~5% of the outside diameter of the axial flow fan and the width of each of the blades is 36. 6~3% of the outside diameter of the axial flow fan.

2. An axial flow fan for a condenser according to claim 1, wherein the outside diameter of the axial flow fan is 150~1mm, the diameter of the hub is 35 : tlmm, and the width of the blade is 55+1mm.

3. An axial flow fan for a condenser according to claim 1, wherein each blade has the maximum camber position of 0.65 uniformly distributed from the hub to the tip, and wherein the maximum camber has curved distributions of 4.0 to 5.0% from the hub to the maximum camber position and of 5.0 to 6.0% from the maximum camber position to the tip.

4. An axial flow fan for a condenser according to claim l, wherein each blade has a pitch angle of 36.0 to 26. 00which is linearly distributed from the hub to the tip, and a sweep angle of67. 00+5%.

5. An axial flow fan for a condenser in a refrigerator, the axial flow fan comprising three blades, wherein the ratio of the inside diameter to the outside diameter is 23.0~5%. the maximum camber position is 0.65 uniformly distributed from the hub to the tip, and the maximum camber has curved distributions of 4. 0 to 5. 0% from the

hub to the maximum camber position and of 5. 0 to 6. 0% from the maximum camber position to the tip.

6. An axial flow fan for a condenser according to claim 5, wherein each of the blade has a pitch angle of 35.0 to 24. 0 which is linearly distributed from the hub to the tip and a sweep angle of 72. 0' 10% at the tip.

7. An axial flow fan for a condenser according to claim 5, wherein the outside

diameter is 110mm, the diameter of the hub is 25+ lmrn, and the width of each of the blades is 36. 0lamm

8. An axial flow fan for a condenser according to claim 5, wherein the axial flow fan is rotatable clockwise or counterclockwise when viewed from the front.

9. An axial flow fan for a condenser according to claim 7, wherein each blade has a boundary divided into 160 areas from the hub-side front progressing clockwise, wherein the rotational axis of the axial flow fan is defined as the Z axis, the horizontal and vertical axes passing through the Z axis are respectively defined as X and

Y axes, and therein the areas have X, Y and Z coordinates according to Table 1 : C : l

No X Y Z 1-9. 368 8. 276-6. 559 2 -9 341 8. 307 -6.544 3 -9.261 8. 396-6. 5 4-9. 129 8. 539-6. 426 5-8. 945 8. 731-6. 323 6 -8 711 8. 965-6. 19 7 -8. 423 9. 236-6. 026 8 -8.084 9 534 -5.831 9 -7 691 9. 8541 -5. 605 10-7 245 10. 186-5 345 11 -6. 746 10. 523-5. 053 12-6 196 10. 857-4. 729 13-5. 595 11. 178 -4. 373 14 4. 948 1 1. 479-3 988 15 -4.257 11.753 -3. 574 16-3. 527 i i. 992-3 136 7-2. 763 12. 191 -2 677 18 -1.972 12.343 -2.199 19-1. 16 12. 446-1. 709 20-0. 335 12. 496 -1 21 21 0.495 12. 49-0. 707 22 1 324 12. 43 -0.206 23 2. 138 12.316 0. 293 24 2. 924 12.153 0. 8 25 3.673 11. 948 1. 309 26 4 381 11 707 1 817 27 5. 045 11. 437 2. 318 28 5.662 11.144 2. 809 29 6. 23 10. 837 3. 284 30 6.748 10. 522 3 742 31 7.216 10.207 4. 177 32 7.634 9. 898 4. 586 33 8. 005 9. 601 4.966 34 8. 328 9.322 5.314 35 8.605 9.066 5. 625 36 8. 838 8. 839 5. 898 37 9.028 8. 645 6.128 38 9.176 8. 489 6. 312 39 9. 282 8. 372 6.447 40 9.346 8. 301 6. 531 41 9. 368 8.276 6. 559 42 9.192 9. 972 6. 643 43 8.952 11. 565 6.753 44 8 671 13. 073 6. 89 45 8. 368 14.51 7. 049 46 8.053 15. 888 7.225 47 7.734 17.218 7 412 48 7.417 18. 506 7.603 49 7.106 19.761 7.789 50 6 804 20. 987 7. 975 51 6. 512 22. 189 8.173 52 6.233 23.371 8.382 53 5. 968 24. 535 8. 602 54 5.698 25.686 8.823

55 5 407 26 836 9.035 56 5.095 27. 977 9.237 57 4 76 S9114 943 58 4.402 30.244 9. 613 59 4. 0SS 31. 36B 9.786 so 3. 621 32. 486 995 61 3. 196 33. 598 10.103 62 2. 748 34.704 10.247 63 2.277 35. 803 10382 64 1. 783 36. 894 10. 506 65 1. 266 37. 979 10. 621 66 0. 726 39. 056 10. 726 67 0. 162 40 125 10.821 68-0. 426 41. 185 10. 906 69 -1 067 42 237 10. 967 70-1. 796 43. 27S 10. 986 71-2 621 44. 298 10.963 72-3. 534 45. 3 10. 9 73-4. 537 46. 278 10. 797 74 -5.63 47 228 10. 656 75 -6.812 48.146 10 477 76 -8.081 49.026 10.187 77-9. 437 49. 865 9. 688 78-10. 88 50. 657 8. 893 79 -12 44 51.39 7.774 80-15. 35 51. 709 5.006 81 -19 85 51. 295 -1 122 32-19. 96 51. 2S-1. 293 S3-20. 3 61 116 -1 665 84 -20.85 50.894 -2.224 85 -21.6 50 58 -2.954 86-22. 54 50. 168-3. 837 87 -23 65 49. 654-4. 854 88-24. 93 49. 028 -5. 984 89-26. 34 48. 281-7. 203 90-27. 89 47. 40S-8. 485 91 -29.55 46. 389 -9. 807 92-31. 3 45. 22S-11 15 93-33. 13 43. 906-12 49 94 -35 42. 423-13. 8 95-36. 91 40. 773-15. 07 96-38. 83 38. 953 -16 28 97-40 73 36. 962 -17 39 98 -42.59 34.805 -18.41 99 -44.38 32. 485 -19 31 100-46. 09 30. 017 -20.09 101 -47 67 27. 442 -20.8 102 -49.1 24.783 -21 47 103-50. 38 22. 064 -22. 07 104 -51.5 19. 307-22. 61 105 -52 46 16. 537-2308 106 -53 25 13. 778-23. 49 107 -53. 88 11.056 -23.82 108 54. 36 8. 395 24. 1 109 -54.69 5.819 -24 31

110 -54.9 3.351 -24 48 111 -54.9 1.012 -24.61 112 -54 99 -1 177 -24.69 113-54 91-3. 199-24. 74 114-54 77-5. 036-24. 77 115 -54.59 -6.672 -24. 78 116 -54.4 -8.093 -24. 78 117 -54 21-9. 285 -24.78 118 -54 04 -10.23 -24 78 119 -53.9 -10.93 -24.8 120 53. 82 11 36 24 84 121 -53.78 -11 5 -24 89 122 -52 11 -13.91 -24 44 123 -50.88 -14.09 -24 11 124-50. 07-13-33-239 125 -49.26 -12.22 -23.68 126-48. 43-111-23 44 127 -47.59 -9.975 -23 18 128 46. 73 8. 848 22. 9 129 -45.86 -7.717 -22.6 103 -44.96 -6.581 -22 29 131 -44.04 -5.44 -21. 95 132 -43.1 -4.294 -21 59 133 -42.13 -3.145 -21. 2 134 -41.14 -1.991 -20. 79 135 -40.12 -0.87 -20 36 136 -39.06 0. 186-19. 91 137-37. 98 1. 178 -19. 45 138 -36 88 2.105 -18 98 139 -35.75 2. 967 -18 49 40 -34. 61 3. 764-18 41 -33.45 4.495 -17 49 42 -32.28 5 161 -16 98 143-31. 1 5 761-16. 46 144 -29. 91 6. 297-15. 94 145 -28. 71 6. 768-1541 146 27. 62 7. 175 14. 88 147 -26. 32 7. 518 -14. 36 148-25. 13 7799-13. 83 149 -23. 94 8. 017 -13 31 150 -22. 76 8 191 -12 78 151 21.57 8.339 -12. 25 152 -20.38 8.461 -11 71 153-19. 18 8. 556-11. 16 154 -17 98 8 623 -10 6 155-16. 77 8. 663-10. 04 156-15. 56 8. 67S-9. 474 157 -14 34 8. 658-8. 901 158 -13 31 8. 611-8323 159 11. 88 8. 533-7 739 160 -10.63 8 422 -7 152 161 9. 368 8. 276-6. 559 Unit: mm ...... table 1.

10. An axial flow fan for a condenser, substantially as hereinbefore described with reference to the accompanying drawings.