Fan coil unit

Abstract

A fan coil unit, including: a blower including a volute, a wind wheel, and a motor; a fan housing; a heat exchanger; and a hydrostatic plate. The volute includes a first chamber, a first air inlet, and a first air outlet. The wind wheel is disposed in the first chamber of the volute. The motor includes an output shaft which extends into the first chamber and is connected to the wind wheel. The fan housing includes a second chamber, a second air inlet, and a second air outlet. The heat exchanger is disposed in the second chamber and is located between the second air inlet and the second air outlet. The volute further includes a volute tongue which is close to the first air outlet. The hydrostatic plate is connected to the volute tongue. The hydrostatic plate includes an upper end and a lower end.

Claims

1. A fan coil unit, comprising: a blower comprising a volute, a wind wheel, and a motor; the volute comprising a first chamber, a first air inlet, a first air outlet having two sides, and a volute tongue; and the motor comprising an output shaft; a heat-exchanger housing comprising a top plate, a bottom plate, a rear plate having a second air inlet, two side plates, a second chamber, and a second air outlet; a heat exchanger; an air-guiding plate comprising an upper end, a lower end, and two side ends; and two air-guiding side plates; wherein: the wind wheel is disposed in the first chamber of the volute; the output shaft extends into the first chamber and is connected to the wind wheel; a top of the first air outlet is connected to a top of the second air inlet; the heat exchanger is disposed in the second chamber and is located between the second air inlet and the second air outlet; the volute tongue is disposed adjacent to the first air outlet; and the air-guiding plate is connected to the volute tongue; the air-guiding plate is disposed in an inclined way; the upper end of the air-guiding plate is connected to the volute tongue, and the lower end of the air-guiding plate extends towards the heat exchanger; the two air-guiding side plates are disposed at the two sides of the first air outlet, respectively; and the two air-guiding side plates are connected to the two side ends of the air-guiding plate, respectively; the lower end of the air-guiding plate is connected to the bottom plate; and the air-guiding plate is inclined with respect to the top plate at an angle a, and 75>a>30; parameters of the volute fulfill the following formula: Hscmax>(Hex1+Hex2); Hex1/D20.112; Hex2/D20.685, wherein Hscmax represents a vertical distance between a center of the wind wheel and a highest point of the volute; Hex2 represents a vertical distance between the top of the first air outlet and a top point of the volute tongue; Hex1 represents a vertical distance between the top point of the volute tongue and the center of the wind wheel; and D2 represents an outer diameter of the wind wheel.

2. The fan coil unit of claim 1, wherein the parameters of the volute fulfill the following formula: 1.652*b2/D21.45, where b2 represents an effective width of the wind wheel, and D2 represents an outer diameter of the wind wheel.

3. The fan coil unit of claim 2, wherein a relation between the effective width of the wind wheel and a width of the volute fulfills the following formula: 0.982*b2/B20.845, where B2 represents the width of the volute.

4. The fan coil unit of claim 3, wherein a relation between an arc radius of the first air inlet of the volute and the outer diameter of the wind wheel fulfills the following formula: 0<r/D20.069, where r represents the arc radius of the first air inlet.

5. The fan coil unit of claim 4, wherein the air-guiding side plates are vertically disposed with regard to the top plate.

6. The fan coil unit of claim 5, wherein the air-guiding side plates extend from the first air outlet to a middle section of the air-guiding plate, and the air-guiding side plates and the air-guiding plate are both disposed in the second chamber.

7. The fan coil unit of claim 6, wherein the air-guiding plate comprises a flat surface for guiding air out from the first air outlet into the second chamber, the second air inlet is located at an upper part of the rear plate, and the second air outlet is located at an upper part of the heat-exchanger housing.

8. The fan coil unit of claim 4, wherein the bottom plate comprises a baseplate and a guide plate connected to the baseplate; the guide plate inclines upwards; an upper end of the guide plate is connected to a bottom of the second air outlet; the top plate, the baseplate, the rear plate, and the two side plates form a rectangular structure; and the second air inlet is disposed at an upper part of the rear plate.

9. The fan coil unit of claim 8, wherein the heat exchanger is disposed vertically or slantly in the second chamber; two ends of the heat exchanger are connected to the top plate and the bottom plate, respectively.

10. The fan coil unit of claim 9, wherein the air-guiding plate comprises a plurality of through holes; a third chamber is confined by the rear plate, the two side plates, the air-guiding plate, and the bottom plate; and the third chamber is filled with the damping material.

11. The fan coil unit of claim 4, wherein the second air inlet is disposed at an upper part of the rear plate; the bottom plate comprises a baseplate having a front portion, and a guide plate that is connected to the front portion of the baseplate; the lower end of the air-guiding plate is connected to the front portion of the baseplate; the guide plate inclines upwards; an upper end of the guide plate is connected to a bottom of the second air outlet; and the second air outlet is enclosed by the two side plates, the top plate, and the upper end of the guide plate.

12. The fan coil unit of claim 11, wherein the front portion of the baseplate is parallel to the top plate; the heat exchanger is disposed vertically or slantly in the second chamber; two ends of the heat exchanger are connected to the top plate and the front portion of the baseplate, respectively.

13. The fan coil unit of claim 12, wherein the air-guiding plate is made of a damping material.

14. The fan coil unit of claim 8, wherein the blower comprises two volutes, two wind wheels, and one motor; two second air inlets are disposed at one side of the heat-exchanger housing; the two volutes are respectively disposed at two sides of the motor; the two wind wheels are disposed in the two volutes, respectively; two shaft extensions of the motor are connected to the two wind wheels, respectively; two first air outlets of the two volutes communicate with the two second air inlets of the heat-exchanger housing, respectively.

15. The fan coil unit of claim 14, wherein the air-guiding plate comprises a curved surface for guiding air out from the two first air outlet into the second chamber, the heat exchanger is slantly disposed, and the air-guiding plate and the heat exchanger tilt towards a same direction.

16. The fan coil unit of claim 1, wherein the parameters of the volute fulfill the following formula: 1.652*b2/D21.45, where b2 represents an effective width of the wind wheel, and D2 represents an outer diameter of the wind wheel.

17. The fan coil unit of claim 16, wherein a relation between the effective width of the wind wheel and a width of the volute fulfills the following formula: 0.982*b2/B20.845, where B2 represents the width of the volute.

18. The fan coil unit of claim 17, wherein a relation between an arc radius of the first air inlet of the volute and the outer diameter of the wind wheel fulfills the following formula: 0<r/D20.069, where r represents the arc radius of the first air inlet.

19. The fan coil unit of claim 18, wherein and the air-guiding side plates are vertically disposed with regard to the top plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described hereinbelow with reference to the accompanying drawings, in which:

(2) FIG. 1 is an exploded view of a fan coil unit in the prior art;

(3) FIG. 2 is a top view of a fan coil unit in the prior art;

(4) FIG. 3 is a sectional view taken from line III-III in FIG. 2;

(5) FIG. 4 is a stereogram of a fan coil unit in Example 1 of the disclosure;

(6) FIG. 5 is an exploded view of a fan coil unit in Example 1 of the disclosure;

(7) FIG. 6 is another exploded view of a fan coil unit in Example 1 of the disclosure;

(8) FIG. 7 is a top view of a fan coil unit in Example 1 of the disclosure;

(9) FIG. 8 is a sectional view taken from line VIII-VIII in FIG. 7;

(10) FIG. 9 illustrates design parameters of a fan coil unit of the disclosure;

(11) FIG. 10 is a comparison diagram of experimental results of the disclosure;

(12) FIG. 11 is a sectional view of a fan coil unit in Example 2 of the disclosure;

(13) FIG. 12 is a sectional view of a fan coil unit in Example 3 of the disclosure;

(14) FIG. 13 is a perspective view from direction XIII in FIG. 12;

(15) FIG. 14 is an exploded view of a fan coil unit in Example 3 of the disclosure;

(16) FIG. 15 is a sectional view of a fan coil unit in Example 4 of the disclosure;

(17) FIG. 16 is a sectional view of a fan coil unit in Example 5 of the disclosure;

(18) FIG. 17 is a stereogram of a fan coil unit in Example 6 of the disclosure;

(19) FIG. 18 is an exploded view of a fan coil unit in Example 6 of the disclosure;

(20) FIG. 19 is another exploded view of a fan coil unit in Example 6 of the disclosure;

(21) FIG. 20 is a top view of a fan coil unit in Example 6 of the disclosure;

(22) FIG. 21 is a sectional view taken from line XXI-XXI in FIG. 20;

(23) FIG. 22 is a front view of a volute in Example 6 of the disclosure;

(24) FIG. 23 is a sectional view taken from line XXIII-XXIII in FIG. 22;

(25) FIG. 24 is a comparison diagram of experimental results in Example 6 of the disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(26) For further illustrating the invention, experiments detailing a fan coil unit are described below.

Example 1

(27) As shown in FIGS. 4-9, a fan coil unit, comprises: a blower 1 comprising a volute 11, a wind wheel 12, and a motor 13; a fan housing 2; a heat exchanger 3; and a hydrostatic plate 4. The volute 11 comprises a first chamber 111, a first air inlet 112, and a first air outlet 113; the wind wheel 12 is disposed in the first chamber 111 of the volute 11; the motor 13 comprises an output shaft 131 which extends into the first chamber 111 and is connected to the wind wheel 12; the fan housing 2 comprises a second chamber 21, a second air inlet 22, and a second air outlet 23; the heat exchanger 3 is disposed in the second chamber 21 and is located between the second air inlet 22 and the second air outlet 23; the volute 11 further comprises a volute tongue which is close to the first air outlet 113; the hydrostatic plate 4 is connected to the volute tongue; the hydrostatic plate 4 is disposed in an inclined way and comprises an upper end and a lower end; and the upper end of the hydrostatic plate 4 is connected to the volute tongue which is close to the first air outlet 113, and the lower end of the hydrostatic plate 4 extends towards the heat exchanger 3.

(28) The hydrostatic plate 4 is a flat slab, the second air inlet 22 is located at an upper part of one end of the fan housing 2, and the second air outlet 23 is located at an upper part of the other end of the fan housing 2.

(29) The fan housing 2 comprises a top plate 24, a bottom plate, a rear plate 27, and side plate 28. The top plate 24, the bottom plate, the rear plate 27, and the side plate 28 enclose the second chamber 21. The second air outlet 22 is disposed on the rear plate 27; the bottom plate comprises the hydrostatic plate 4, a middle plate 25, and a guide plate 26 which are connected successively; the lower end of the hydrostatic plate 4 is connected to the middle plate 25 of the fan housing 2; the guide plate 26 inclines upwards; an upper end of the guide plate 26 is connected to a bottom of the second air outlet 23; and the second air outlet 23 is enclosed by the side plate 28, the top plate 24, and the upper end of the guide plate 26. The middle plate 25 is parallel to the top plate 24; the heat exchanger 3 is disposed vertically or slantly in the second chamber; two ends of the heat exchanger 3 are connected to the top plate 24 and the middle plate 25, respectively. The hydrostatic plate 4 is made of damping material.

(30) The blower 1 comprises two volutes 11, two wind wheels 12, and one motor 13; two second air inlets 22 are disposed at one side of the fan housing 2; the two volutes 11 are respectively disposed at two sides of the motor 13; the two wind wheels 12 are disposed in the two volutes 11, respectively; two shaft extensions of the motor 13 are connected to the two wind wheels 12, respectively; two first air outlets 113 of the two volutes 11 communicate with the two second air inlets 22 of the fan housing 2, respectively.

(31) As shown in FIG. 9, the angle a of inclination of the hydrostatic plate 4 is 75>a>30; the parameters of the volute 11 fulfill the following formula: Hscmax>(Hex1+Hex2); Hex1/D20.112; Hex2/D20.685, Hscmax represents a vertical distance between a center of the wind wheel 12 and a highest point of the volute; where Hex2 represents a vertical distance between a top of the second air outlet and a top point of the volute tongue; Hex1 represents a vertical distance between the top point of the volute tongue and the center of the wind wheel 12; and D2 represents an outer diameter of the wind wheel 12. Tests show that, the results are ideal when a=30, a=35, a=40, a=45, a=50, a=60, and a=75. As shown in FIG. 10, when the angle a of inclination is 43, based on the testing conditions in Table 1, the experimental results are listed in Tables 2, 3, and 4. Table 5 lists the experimental result in the presence of the hydrostatic plate. The experimental results are shown in four curves in FIG. 10, that is, Curve A1, Curve A2, Curve A3, Curve A4. Curve A1 fulfills the following conditions: Hscmax>(Hex1+Hex2); Hex1/D20.055; Hex2/D20.883. Curve A2 and Curve A3 are in the critical conditions. Curve A1 has the highest efficiency when the output wind is less than 10 units. Curve A4 is the experimental result in the presence of the hydrostatic plate in Table 5, with the lowest efficiency.

(32) TABLE-US-00001 TABLE 1 Number of revolutions n.sub.n (rpm) = 815.00 Normal atmosphere Pan (hPa) = 1013.00 Standard temperature tan ( C.) = 25.00 Air density a (kg/m.sup.3) = 1.1767

(33) TABLE-US-00002 TABLE 2 Testing conditions I: Hsc.sub.max > (Hex.sub.1 + Hex.sub.2 + 14); a = 43 Hex.sub.1/D.sub.2 = 0.248; Hex.sub.2/D.sub.2 = 0.549: Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1408.98 23.48 0.02 35.38 3.98 9.31 9.33 0.02 10.32 1256.99 20.95 11.21 30.10 3.55 7.41 18.62 13.00 21.60 1027.96 17.13 26.01 23.46 2.90 4.95 30.96 31.66 37.69 807.73 13.46 31.73 17.14 2.28 3.06 34.79 41.55 45.56 712.25 11.87 34.18 14.69 2.01 2.38 36.56 46.04 49.25 604.96 10.08 36.77 12.50 1.71 1.72 38.49 49.42 51.73 501.25 8.35 39.20 10.48 1.41 1.18 40.38 52.09 53.66 382.78 6.38 41.14 8.23 1.08 0.69 41.83 53.18 54.07 173.01 2.88 42.38 4.76 0.49 0.14 42.52 42.78 42.92

(34) TABLE-US-00003 TABLE 3 Testing conditions II: Hsc.sub.max = (Hex.sub.1 + Hex.sub.2); a = 43 Hex.sub.1/D.sub.2 = 0.248; Hex.sub.2/D.sub.2 = 0.549: Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1486.26 24.77 0.02 38.05 4.20 10.36 10.38 0.02 11.26 1358.33 22.64 12.72 33.73 3.83 8.65 21.37 14.23 23.91 995.11 16.59 24.97 22.18 2.81 4.64 29.61 31.12 36.91 791.21 13.19 31.62 17.05 2.23 2.94 34.55 40.76 44.54 695.71 11.60 34.65 14.91 1.96 2.27 36.92 44.92 47.86 584.36 9.74 37.01 12.56 1.65 1.60 38.61 47.82 49.89 472.83 7.88 39.17 10.29 1.33 1.05 40.22 49.99 51.33 366.29 6.10 41.31 8.22 1.03 0.63 41.94 51.16 51.94 173.39 2.89 42.74 4.94 0.49 0.14 42.88 41.69 41.83

(35) TABLE-US-00004 TABLE 4 Testing conditions III: Hsc.sub.max = (Hex.sub.1 + Hex.sub.2 + 14); a = 43 Hex.sub.1/D.sub.2 = 0.112: Hex.sub.2/D.sub.2 = 0.685: Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1453.82 24.23 0.02 37.97 4.10 9.91 9.93 0.02 10.56 1278.48 21.31 11.64 31.38 3.61 7.66 19.31 13.17 21.85 976.20 16.27 24.94 22.21 2.76 4.47 29.41 30.45 35.91 788.84 13.15 32.22 17.68 2.23 2.92 35.14 39.93 43.54 693.25 11.55 34.77 15.12 1.96 2.25 37.02 44.28 47.15 545.88 9.10 35.75 11.44 1.54 1.40 37.15 47.37 49.22 464.78 7.75 38.93 10.15 1.31 1.01 39.94 49.51 50.80 324.00 5.40 40.41 7.47 0.91 0.49 40.91 48.66 49.25 173.20 2.89 41.34 4.85 0.49 0.14 41.48 41.03 41.17

(36) TABLE-US-00005 TABLE 5 Testing conditions IV: No hydrostatic plate Hscmax = (Hex1 + Hex2 + 14); Hex.sub.1/D.sub.2 = 0.248: Hex.sub.2/D.sub.2 = 0.549: Air outlet of volute Blower Outgoing Static Total Rotation Air Air Static Output Blowing dynamic Total pressure pressure speed volume volume pressure power speed pressure pressure efficiency efficiency n (rpm) Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 815.00 1372.25 22.87 0.01 27.11 4.19 10.32 10.33 0.01 11.45 815.00 1296.16 21.60 5.41 32.41 3.97 9.25 14.66 6.28 17.03 815.00 1211.07 20.18 10.91 29.04 3.59 7.60 18.51 12.83 21.76 815.00 946.83 15.78 24.54 21.09 2.77 4.51 29.05 30.61 36.23 815.00 849.84 14.16 28.22 18.61 2.48 3.63 31.85 35.79 40.40 815.00 760.94 12.68 31.66 16.05 2.22 2.91 34.57 41.70 45.53 815.00 622.65 10.38 33.60 12.91 1.82 1.95 35.55 45.01 47.62 815.00 508.48 8.47 36.34 10.91 1.49 1.30 37.64 47.06 48.74 815.00 352.32 5.87 43.60 8.91 1.03 0.62 43.77 47.86 48.05 815.00 227.83 3.80 49.69 7.67 0.67 0.26 49.95 41.00 41.22

Example 2

(37) As shown in FIG. 11, the fan coil unit in this example is basically the same as that in Example 1 except that: the heat exchanger 3 is slantly disposed, the upper end and the lower end of the heat exchanger 3 are connected to the top plate 24 and the middle plate 25, respectively. The heat exchanger 3 is no longer vertical to the top plate 24 and the middle plate 25.

Example 3

(38) As shown in FIGS. 12-14, the fan coil unit in this example is basically the same as that in Example 1 except that: the fan housing 2 comprises a top plate 24, a bottom plate, a rear plate 27, and side plate 28; the bottom plate comprises a baseplate 29 and a guide plate 26 connected to the baseplate 29; the guide plate 26 inclines upwards; an upper end of the guide plate 26 is connected to a bottom of the second air outlet 23; the top plate 24, the baseplate 29, the rear plate 27, and the side plate 28 form a rectangular structure; and the second air outlet 22 is disposed at a top of the rear plate 27.

(39) The heat exchanger 3 is disposed vertically in the second chamber; two ends of the heat exchanger 3 are connected to the top plate 24 and the baseplate 29, respectively; the lower end of the hydrostatic plate 4 is connected to the bottom plate of the fan housing 2.

(40) The hydrostatic plate 4 comprises a plurality of through holes 41, a third chamber 42 is disposed below the hydrostatic plate 4, and third chamber 42 is filled with damping material.

Example 4

(41) As shown in FIG. 15, the fan coil unit in this example is basically the same as that in Example 3 except that: the heat exchanger 3 is slantly disposed.

Example 5

(42) As shown in FIG. 16, the fan coil unit in this example is basically the same as that in Example 4 except that: the heat exchanger 3 is slantly disposed; the hydrostatic plate 4 is a curved plate with depressed middle part, the heat exchanger 3 is slantly disposed, and the direction of tilt thereof is the same as that of the hydrostatic plate 4. Specifically, the hydrostatic plate 4 and the heat exchanger 3 tilt towards the same direction.

Example 6

(43) As shown in FIGS. 17-24, a fan coil unit, comprises: a blower 1 comprising a volute 11, a wind wheel 12, and a motor 13; a fan housing 2; a heat exchanger 3; and a hydrostatic plate 4. The volute 11 comprises a first chamber 111, a first air inlet 112, and a first air outlet 113; the wind wheel 12 is disposed in the first chamber 111 of the volute 11; the motor 13 comprises an output shaft 131 which extends into the first chamber 111 and is connected to the wind wheel 12; the fan housing 2 comprises a second chamber 21, a second air inlet 22, and a second air outlet 23; the heat exchanger 3 is disposed in the second chamber 21 and is located between the second air inlet 22 and the second air outlet 23; the volute 11 further comprises a volute tongue which is close to the first air outlet 113; the hydrostatic plate 4 is connected to the volute tongue; the hydrostatic plate 4 is disposed in an inclined way and comprises an upper end and a lower end; and the upper end of the hydrostatic plate 4 is connected to the volute tongue which is close to the first air outlet 113, and the lower end of the hydrostatic plate 4 extends towards the heat exchanger 3. The hydrostatic plate 4 is a flat slab.

(44) The hydrostatic side plates 5 are disposed at two sides of the first air outlet 113, respectively; bottom ends of the hydrostatic side plates 5 are connected to two side ends of the hydrostatic plate 4, and the hydrostatic side plates 5 are vertically disposed with regard to the ground. The hydrostatic side plates 5 extend from the first air outlet 113 to a middle section of the hydrostatic plate 4, and the hydrostatic side plates 5 and the hydrostatic plate 4 are both disposed in the second chamber 21.

(45) The hydrostatic plate 4 is a vertical slab, the second air inlet 22 is located at an upper part of one end of the fan housing 2, and the second air outlet 23 is located at an upper part of the other end of the fan housing 2.

(46) The fan housing 2 comprises a top plate 24, a bottom plate, a rear plate 27, and side plate 28; the bottom plate comprises a baseplate 29 and a guide plate 26 connected to the baseplate 29; the guide plate 26 inclines upwards; an upper end of the guide plate 26 is connected to a bottom of the second air outlet 23; the top plate 24, the baseplate 29, the rear plate 27, and the side plate 28 form a rectangular structure; and the second air outlet 22 is disposed at a top of the rear plate 27.

(47) The heat exchanger 3 is disposed vertically or slantly in the second chamber; two ends of the heat exchanger 3 are connected to the top plate 24 and the bottom plate, respectively.

(48) The middle plate 25 is parallel to the top plate 24. The heat exchanger 3 is disposed vertically or slantly in the second chamber. Two ends of the heat exchanger 3 are connected to the top plate 24 and the middle plate 25, respectively.

(49) The blower 1 comprises two volutes 11, two wind wheels 12, and one motor 13; two second air inlets 22 are disposed at one side of the fan housing 2; the two volutes 11 are respectively disposed at two sides of the motor 13; the two wind wheels 12 are disposed in the two volutes 11, respectively; two shaft extensions of the motor 13 are connected to the two wind wheels 12, respectively; two first air outlets 113 of the two volutes 11 communicate with the two second air inlets 22 of the fan housing 2, respectively.

(50) As shown in FIG. 23, in the presence of the hydrostatic plate 4 and the hydrostatic side plates 5, the parameters of the volute 11 fulfill the following formula: 1.652*b2/D21.45, where b2 represents an effective width of the wind wheel 12, and D2 represents an outer diameter of the wind wheel 12. The relation between the effective width of the wind wheel 12 and a width of the volute 11 fulfills the following formula: 0.982*b2/B20.845, where B2 represents the width of the volute 11. The relation between an arc radius of the first air inlet 112 of the volute 11 and the outer diameter of the wind wheel 12 fulfills the following formula: 0<r/D20.069, where r represents the arc radius of the first air inlet 112.

(51) Based on the abovementioned structural parameters and the testing conditions in Table 6, the following experimental verifications are performed:

(52) The experimental parameters in Table 7 are as follows: 2b2/D2=1.2625, 2b2/B2=0.796, r/D2=0.075. The measured efficiency values corresponding to different air volumes are recorded and used for fitting a curve A1 as shown in FIG. 24.

(53) The experimental parameters in Table 8 are as follows: 2b2/D2=1.4296, 2b2/B2=0.796, r/D2=0.1096. The measured efficiency values corresponding to different air volumes are recorded and used for fitting a curve A2 as shown in FIG. 24.

(54) The experimental parameters in Table 9 are as follows: 2b2/D2=1.43, 2b2/B2=0.832, r/D2=0.163. The measured efficiency values corresponding to different air volumes are recorded and used for fitting a curve A3 as shown in FIG. 24.

(55) The experimental parameters in Table 10 are as follows: 2b2/D2=1.45, 2b2/B2=0.845, r/D2=0.069. The measured efficiency values corresponding to different air volumes are recorded and used for fitting a curve A4 as shown in FIG. 24.

(56) The experimental parameters in Table 11 are as follows: 2b2/D2=1.45, 2b2/B2=0.874, r/D2=0.055. The measured efficiency values corresponding to different air volumes are recorded and used for fitting a curve A5 as shown in FIG. 24.

(57) The experimental parameters in Table 12 are as follows: 2b2/D2=1.48, 2b2/B2=0.894, r/D2=0.047. The measured efficiency values corresponding to different air volumes are recorded.

(58) The experimental parameters in Table 13 are as follows: 2b2/D2=1.65, 2b2/B2=0.98, r/D2=0.03. The measured efficiency values corresponding to different air volumes are recorded.

(59) The curve graph as shown in FIG. 24 is obtained according to the six groups of experimental data, and comprises Curve A1, Curve A2, Curve A3, Curve A4, and Curve A5. Based on the curve graph in FIG. 24, in Curve A4 and Curve A5, the parameters of the volute 11 fulfill the following formula: 1.652*b2/D21.45, 0.982*b2/B20.845, and 0<r/D20.069, so the work efficiency of the motor is relatively high when the output air volume is between 0 and 10 units. Curve A1, Curve A2 and Curve A3 do not meet the above requirements, so the work efficiency of the motor is relatively low when the output air volume is between 0 and 10 units. In addition, compare the experimental parameters in Tables 12 and 13 with the experimental parameters in Table 11, it is known that the work efficiency of the motor operating under the experimental parameters in Tables 12 and 13 with the output air volume of between 0 and 10 units is relatively high. In practice, the output air volume of the motor is generally between 0 and 10 units, so the core objective of the invention is to find out an operating parameter under which the motor exhibits the highest working efficiency.

(60) TABLE-US-00006 TABLE 6 Number of revolutions n.sub.n (rpm) = 800.00 Normal atmosphere Pan (hPa) = 1013.00 Standard temperature tan ( C.) = 25.00 Air density a (kg/m.sup.3) = 1.1767

(61) TABLE-US-00007 TABLE 7 A1: 2b2/D2 = 1.2625 Blower 2b2/B2 = 0.796 r/D2 = 0.075 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1489.55 24.83 0.02 44.23 7.82 35.99 36.02 0.02 33.69 1305.88 21.76 14.88 38.41 6.86 27.66 42.55 14.06 40.19 1053.72 17.56 32.95 29.85 5.53 18.01 50.96 32.32 49.98 856.39 14.27 40.71 24.40 4.50 11.90 52.60 39.68 51.28 765.96 12.77 44.31 22.56 4.02 9.52 53.83 41.80 50.77 675.75 11.26 46.72 20.23 3.55 7.41 54.13 43.36 50.23 561.04 9.35 47.76 17.55 2.95 5.11 52.87 42.40 46.93 433.58 7.23 47.96 14.52 2.28 3.05 51.00 39.77 42.30 247.22 4.12 48.89 10.25 1.30 0.99 49.88 32.75 33.42

(62) TABLE-US-00008 TABLE 8 A2: 2b2/D2 = 1.4296 2b2/B2 = 0.796 r/D2 = 0.1096 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1154.66 19.24 0.01 18.18 4.18 10.26 10.27 0.02 14.23 1104.61 18.41 3.69 21.94 3.99 9.39 13.08 5.16 18.29 1041.53 17.36 8.19 20.61 3.77 8.35 16.54 11.50 23.22 825.79 13.76 19.79 15.82 2.99 5.25 25.03 28.69 36.30 746.50 12.44 23.48 14.13 2.70 4.29 27.76 34.45 40.74 652.10 10.87 26.52 12.25 2.36 3.27 29.79 39.21 44.04 531.09 8.85 29.11 10.30 1.92 2.17 31.28 41.70 44.81 427.51 7.13 31.71 8.51 1.55 1.41 33.12 44.25 46.21 248.67 4.14 37.41 6.26 0.90 0.48 37.89 41.28 41.81

(63) TABLE-US-00009 TABLE 9 A3: 2b2/D2 = 1.43 2b2/B2 = 0.832 r/D2 = 0.163 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1405.89 23.43 0.01 26.86 4.11 9.94 9.95 0.01 11.35 1331.20 22.19 5.21 31.45 3.89 8.91 14.12 6.12 16.60 1206.45 20.11 10.52 27.43 3.53 7.32 17.84 12.85 21.79 929.41 15.49 23.65 20.82 2.72 4.35 27.99 29.32 34.71 834.20 13.90 27.19 18.50 2.44 3.50 30.69 34.06 38.45 746.94 12.45 30.50 16.67 2.18 2.81 33.31 37.96 41.46 611.19 10.19 32.37 13.70 1.79 1.88 34.25 40.12 42.45 499.12 8.32 35.01 11.92 1.46 1.25 36.26 40.71 42.17 345.84 5.76 41.57 10.17 1.01 0.60 42.17 39.28 39.84

(64) TABLE-US-00010 TABLE 10 A4: 2b2/D2 = 1.45 2b2/B2 = 0.845 r/D2 = 0.069 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1391.89 23.20 0.02 35.26 3.93 9.18 9.20 0.02 10.09 1247.95 20.80 11.31 30.60 3.52 7.38 18.70 12.81 21.18 999.17 16.65 25.13 22.83 2.82 4.73 29.86 30.55 36.31 769.54 12.83 31.39 17.58 2.17 2.81 34.19 38.17 41.58 666.67 11.11 33.65 14.81 1.88 2.11 35.76 42.07 44.71 576.99 9.62 36.57 13.01 1.63 1.58 38.14 45.04 46.98 472.64 7.88 38.62 10.60 1.33 1.06 39.68 47.84 49.15 352.68 5.88 40.46 8.30 1.00 0.59 41.05 47.75 48.45 169.83 2.83 42.24 5.30 0.48 0.14 42.38 37.62 37.74

(65) TABLE-US-00011 TABLE 11 A5: 2b2/D2 = 1.45 2b2/B2 = 0.874 r/D2 = 0.055 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1547.07 25.78 0.02 41.96 4.33 11.04 11.06 0.02 11.33 1370.45 22.84 13.11 35.13 3.84 8.66 21.77 14.21 23.60 1108.25 18.47 28.51 26.69 3.10 5.67 34.18 32.89 39.42 879.89 14.66 33.74 19.99 2.46 3.57 37.31 41.25 45.62 769.23 12.82 36.49 17.77 2.15 2.73 39.22 43.87 47.16 650.98 10.85 38.10 14.85 1.82 1.95 40.06 48.41 48.79 577.30 9.62 40.74 13.14 1.62 1.54 42.28 49.72 51.60 391.82 6.53 40.95 9.46 1.10 0.71 41.66 47.11 47.92 168.47 2.81 41.42 5.28 0.47 0.13 41.55 36.69 36.80

(66) TABLE-US-00012 TABLE 12 A6: 2b2/D2 = 1.48 2b2/B2 = 0.894 r/D2 = 0.047 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) vd (m/s) Pd (Pa) Pt (Pa) sf () tf () 1565.22 26.09 0.03 45.33 4.17 10.25 10.28 0.03 9.86 1361.08 22.68 16.42 36.14 3.63 7.75 24.17 17.18 25.29 1041.01 17.35 31.43 24.79 2.78 4.53 35.97 36.66 41.95 811.05 13.52 36.16 18.36 2.16 2.75 38.91 44.36 47.74 692.85 11.55 37.39 15.21 1.85 2.01 39.40 47.31 49.85 626.57 10.44 39.68 13.49 1.67 1.64 41.33 51.21 53.33 535.59 8.93 41.67 11.93 1.43 1.20 42.87 51.98 53.47 382.57 6.38 41.54 8.73 1.02 0.61 42.15 50.59 51.34 174.75 2.91 45.67 5.42 0.47 0.13 45.80 40.89 41.00

(67) TABLE-US-00013 TABLE 13 A7: 2b2/D2 = 1.65 2b2/B2 = 0.98 r/D2 = 0.03 Air outlet of volute Blower Outgoing Static Total Air Static Output Blowing dynamic Total pressure pressure Air volume volume pressure power speed pressure pressure efficiency efficiency Q (m.sup.3/h) Q (m.sup.3/min) Ps (Pa) Lmo (W) Vd (m/s) Pd (Pa) Pt (Pa) Hsf () Htf () 1570.11 27.12 0.04 47.53 4.01 9.55 10.18 0.04 10.64 1365.01 22.91 18.29 37.25 3.42 7.14 23.48 20.76 27.53 1080.11 16.99 33.28 25.83 2.85 3.54 35.61 40.98 42.15 800.24 14.11 36.83 20.50 1.98 2.11 38.12 46.73 49.52 718.62 11.98 38.28 18.25 1.86 1.56 40.56 49.57 51.25 670.35 10.55 40.18 12.03 1.57 1.20 42.12 53.16 54.84 550.45 9.34 42.98 10.48 1.18 0.95 43.36 53.91 55.79 386.87 6.41 43.12 8.36 0.47 0.49 44.48 52.86 52.74 170.63 2.99 46.82 6.18 0.29 0.13 46.99 42.56 43.58

(68) Unless otherwise indicated, the numerical ranges involved in the invention include the end values. While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.