A low-noise and high-reliability bus air-conditioning centrifugal fan and air-conditioning

Abstract

A low-noise and high-reliability bus air-conditioning centrifugal fan and air-conditioning, relating to the technical field of air-conditioning, the low-noise and high-reliability bus air-conditioning centrifugal fan comprises a centrifugal fan body, the length of the air outlet of the centrifugal fan body is L, the width of the air outlet of the centrifugal fan body is W, and the following relationship is satisfied: 2≥L / W≥1.2. The present invention ensures that the air outlet of the centrifugal fan is more uniform, reduces local vortices, and thus reduces the noise of the centrifugal fan, effectively improves the noise level of the centrifugal fan, increases the reliability of the performance of the bus air-conditioning, and thus increases the comfort of the bus.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to a low-noise and high-reliability bus air conditioning centrifugal fan and air conditioner. Background Art

[0002] With the development of economy and the improvement of people's living standards, passengers have higher and higher requirements for the riding environment, especially the comfort of the interior environment, including the noise level in the car, temperature rise and temperature drop and other key parameters, which put forward higher requirements for bus air conditioning. The new national standard has increased the noise level on the indoor side of bus air conditioning from the original 70dB(A) to 65dB(A), and the noise requirements are getting higher and higher.

[0003] The bus air conditioner is the main noise source inside the bus. The centrifugal fan is the air supply component inside the bus air conditioner and is also the main noise source of the bus air conditioner. Only by improving the noise level of the centrifugal fan can we meet the increasingly stringent noise requirements. The design of the centrifugal fan directly determines the reliability of the bus air conditioner's performance and the comfort of the bus. Summary of the invention

[0004] One of the purposes of the present invention is to avoid the deficiencies in the prior art and provide a low-noise and high-reliability bus air-conditioning centrifugal fan, which can effectively improve the noise level of the centrifugal fan, increase the reliability of the performance of the bus air-conditioning, and thus increase the comfort of the bus.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A low-noise and high-reliability bus air conditioner centrifugal fan is provided, comprising a centrifugal fan body, the length of the air outlet of the centrifugal fan body is L, the width of the air outlet of the centrifugal fan body is W, and the following relationship is satisfied: 2≥L / W≥1.2. By reasonably designing the length-to-width ratio of the air outlet of the centrifugal fan, the centrifugal fan can ensure that the air outlet is more uniform, reduce local vortices, and thus reduce the noise of the centrifugal fan, effectively improve the noise level of the centrifugal fan, increase the reliability of the performance of the bus air conditioner, and thus increase the comfort of the bus.

[0007] Furthermore, the centrifugal fan body includes a motor with two output ends, and centrifugal fan blades respectively arranged at the two output ends of the motor, and a volute arranged outside the centrifugal fan blades, and mounting plates respectively fixed to the motor and the volute, the air outlet of the centrifugal fan body is located on the mounting plate, and the air outlet of the centrifugal fan body is connected to the interior of the volute.

[0008] Furthermore, a guide ring is provided at one end of the volute close to the motor, the axial distance between the side of the guide ring close to the motor and the end face of the motor is d, the diameter of the centrifugal fan blade is D, d / D is x, the relative air volume is y, and the following relationship is satisfied:

[0009] y=-3.2495x 2 +2.4306x+0.5709, 0.3≥x>0;

[0010] y=1,x>0.3. The axial distance between the side of the guide ring close to the motor and the end face of the motor is d, which is the effective air inlet distance. The ratio of d / D will directly affect the air volume of the centrifugal fan, and the symmetry of the air inlet on the left and right sides and the middle of the centrifugal fan, and then affect the uniformity of the air outlet of the centrifugal fan. Among them, y is the relative air volume, which means the ratio of the current air volume to the ideal air volume.

[0011] Furthermore, d / D=x≥0.2. When the ratio of d / D is x≥0.2, the air inlet on the left and right sides of the centrifugal fan can be symmetrical with the middle, reducing the air inlet resistance and increasing the air volume of the centrifugal fan. At the same time, it can ensure that the air outlet of the centrifugal fan is more uniform, reduce local vortices, and thus reduce the noise of the centrifugal fan, effectively improve the noise level of the centrifugal fan, increase the reliability of the performance of the bus air conditioner, and thus increase the comfort of the bus.

[0012] Furthermore, d / D=x=0.25. In view of the limitation of structural space, when the ratio of d / D is x=0.25, a balance point is found between the limitation of structural space and the performance of centrifugal fan, which can not only meet the limitation of structural space, but also make the air inlet of the left and right sides of the centrifugal fan symmetrical with that of the middle, reduce the air inlet resistance, increase the air volume of the centrifugal fan, and at the same time ensure that the air outlet of the centrifugal fan is more uniform, reduce the local vortex, thereby reducing the noise of the centrifugal fan, effectively improve the noise level of the centrifugal fan, increase the reliability of the performance of the bus air conditioner, and thus increase the comfort of the bus.

[0013] Furthermore, the mounting plate includes a mounting plate body, and a motor mounting boss integrally formed with the mounting plate body and located in the middle of the mounting plate body, the motor mounting boss is provided with two groups of fixing holes for fixing the motor, the spacing of one group of fixing holes is a, the spacing of the other group of fixing holes is b, and the difference between a and b is greater than 2 times the diameter of the fixing holes. The mounting plate and the motor mounting boss are designed as an integral molding. Compared with the two components connected by bolts or rivets, the motor mounting boss has better strength and higher centrifugal fan assembly efficiency. At the same time, due to the different spacings between the two groups of fixing holes, it is beneficial to the positioning of the motor and effectively prevents the motor from being installed upside down.

[0014] Furthermore, the volute includes a lower volute fixed to the mounting plate, and an upper volute matched with the lower volute, and the lower volute is embedded with a nut for fixing the upper volute. By embedding the nut in the lower volute, it is beneficial to directly fix the upper volute to the lower volute through the stud, so as to improve the assembly efficiency of the centrifugal fan while ensuring the fastening, safety and reliability of the volute.

[0015] Furthermore, volute reinforcement plates are provided at both ends of the lower volute, and the installation position of the lower volute is located between the reinforcement plate and the mounting plate. The installation position of the lower volute is located between the reinforcement plate and the mounting plate, and the reinforcement plate is fixed by countersunk screws and washer nuts to disperse the fastening force, prevent stress concentration, and ensure installation reliability.

[0016] Furthermore, the lower volute is provided with a wire buckle integrally formed with the lower volute. The wire buckle is used to fix the power cord of the centrifugal fan, eliminating the use of wire ties, which can effectively eliminate the risk of wire cutting caused by fixing the general centrifugal fan on the mounting plate with wire ties, and at the same time improve the assembly efficiency of the centrifugal fan.

[0017] Beneficial effects of the present invention: A low-noise and high-reliability bus air conditioning centrifugal fan of the present invention comprises a centrifugal fan body, the length of the air outlet of the centrifugal fan body is L, the width of the air outlet of the centrifugal fan body is W, and the following relationship is satisfied: 2≥L / W≥1.2. The present invention ensures that the air outlet of the centrifugal fan is more uniform and reduces local vortices by reasonably designing the length-to-width ratio of the air outlet of the centrifugal fan, thereby reducing the noise of the centrifugal fan, effectively improving the noise level of the centrifugal fan, increasing the reliability of the performance of the bus air conditioning, and thus increasing the comfort of the bus.

[0018] The second object of the present invention is to avoid the deficiencies in the prior art and provide an air conditioner, which uses the above-mentioned low-noise and high-reliability bus air-conditioning centrifugal fan. By reasonably designing the length-to-width ratio of the air outlet of the centrifugal fan, the air outlet of the centrifugal fan is ensured to be more uniform, and the local vortex is reduced, thereby reducing the noise of the centrifugal fan, effectively improving the noise level of the centrifugal fan, increasing the reliability of the performance of the bus air conditioner, and thereby increasing the comfort of the bus. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0020] Figure 1 It is a bottom view of the overall structure of a low-noise and high-reliability bus air-conditioning centrifugal fan of the present invention.

[0021] Figure 2 It is an exploded view of the overall structure of a low-noise and high-reliability bus air-conditioning centrifugal fan of the present invention.

[0022] Figure 3 It is a schematic diagram of the overall structure of a lower volute of a low-noise and high-reliability bus air-conditioning centrifugal fan of the present invention.

[0023] Figure 4 It is a front view of the overall structure of a low-noise and high-reliability bus air-conditioning centrifugal fan of the present invention.

[0024] Figure 5 It is a graph of d / D ratio and relative air volume.

[0025] Figure 6 This is a comparison of the simulated flow fields of a general fan (left) and the invented fan (right).

[0026] Figure 7 It is the noise curve diagram of different gears of general fans and invented fans.

[0027] Figure 8 It is a comparison of the noise, air volume and power data of general fans and invented fans.

[0028] Included in the picture are:

[0029] Centrifugal fan 1, air outlet 2, motor 3, centrifugal fan blade 4, volute 5, mounting plate 6, guide ring 7, motor mounting boss 8, fixing hole 9, lower volute 10, upper volute 11, nut 12, reinforcement plate 13, wire buckle 14. DETAILED DESCRIPTION

[0030] The present invention is further described in conjunction with the following examples.

[0031] Example 1

[0032] A low-noise and high-reliability bus air conditioning centrifugal fan of this embodiment, such as Figure 1-4 As shown, it includes a centrifugal fan 1 body, the length of the air outlet 2 of the centrifugal fan 1 body is L, the width of the air outlet 2 of the centrifugal fan 1 body is W, and the following relationship is satisfied: 2≥L / W≥1.2. By reasonably designing the length-to-width ratio of the air outlet 2 of the centrifugal fan 1, it is ensured that the air outlet of the centrifugal fan 1 is more uniform, the local vortex is reduced, and thus the noise of the centrifugal fan 1 is reduced, the noise level of the centrifugal fan 1 is effectively improved, the reliability of the performance of the bus air conditioner is increased, and the comfort of the bus is increased.

[0033] The centrifugal fan 1 body includes a motor 3 with two output ends, centrifugal blades 4 respectively arranged at the two output ends of the motor 3, a volute 5 arranged outside the centrifugal blades 4, and a mounting plate 6 respectively fixed to the motor 3 and the volute 5, the air outlet 2 of the centrifugal fan 1 body is located on the mounting plate 6, and the air outlet 2 of the centrifugal fan 1 body is connected to the inside of the volute 5. The centrifugal blades 4 are axially fixed to the output ends of the motor 3 by nuts and bolts, and the thread directions of the nuts and bolts are opposite, so as to ensure that the nuts and bolts are tightened during the rotation of the centrifugal blades 4.

[0034] The end of the volute 5 close to the motor 3 is provided with a guide ring 7, the axial distance between the side of the guide ring 7 close to the motor 3 and the end surface of the motor 3 is d, the diameter of the centrifugal fan blade 4 is D, d / D is x, the relative air volume is y, and the following relationship is satisfied:

[0035] y=-3.2495x 2 +2.4306x+0.5709, 0.3≥x>0;

[0036] y=1,x>0.3. The equation curve is as follows Figure 5 As shown, when 0.3≥x>0, the curve increases monotonically, and this section belongs to the parameter sensitive area. When x>0.3, the curve increases monotonically and the curve remains constant, and this section belongs to the parameter-independent area. The axial distance between the side of the guide ring 7 close to the motor 3 and the end face of the motor 3 is d, and this distance is the effective air inlet distance. The ratio of d / D will directly affect the air volume of the centrifugal fan 1, and the symmetry of the left and right sides and the middle air inlet of the centrifugal fan 1, and then affect the uniformity of the air outlet of the centrifugal fan 1. Among them, y is the relative air volume, which represents the ratio of the current air volume to the ideal air volume.

[0037] When the ratio x of d / D is ≥ 0.2, the left and right sides of the centrifugal fan 1 can be made symmetrical with the middle air inlet, thereby reducing the air inlet resistance and increasing the air volume of the centrifugal fan 1. At the same time, it can ensure that the air outlet of the centrifugal fan 1 is more uniform, reduce local eddies, and thus reduce the noise of the centrifugal fan 1, effectively improve the noise level of the centrifugal fan 1, increase the reliability of the performance of the bus air conditioner, and thereby increase the comfort of the bus.

[0038] In view of the structural space limitation, when the ratio of d / D is x=0.25, a balance point is found between the structural space limitation and the performance of the centrifugal fan 1, which can not only meet the structural space limitation, but also make the left and right sides of the centrifugal fan 1 symmetrical with the middle air inlet, reduce the air inlet resistance, and increase the air volume of the centrifugal fan 1. At the same time, it can ensure that the air outlet of the centrifugal fan 1 is more uniform, reduce local eddy currents, thereby reducing the noise of the centrifugal fan 1, effectively improving the noise level of the centrifugal fan 1, and increasing the reliability of the performance of the bus air conditioner, thereby increasing the comfort of the bus.

[0039] The mounting plate 6 includes a mounting plate 6 body, and a motor mounting boss 8 integrally formed with the mounting plate 6 body and located in the middle of the mounting plate 6 body, the motor mounting boss 8 is provided with two groups of fixing holes 9 for fixing the motor 3, wherein the spacing of one group of fixing holes 9 is a, and the spacing of the other group of fixing holes 9 is b, and the difference between a and b is greater than 2 times the diameter of the fixing holes 9. The mounting plate 6 and the motor mounting boss 8 are integrally formed, and compared with the two components connected by bolts or rivets, the strength of the motor mounting boss 8 is better, and the assembly efficiency of the centrifugal fan 1 is higher. At the same time, due to the different spacings of the two groups of fixing holes 9, it is beneficial to the positioning of the motor 3 and effectively prevent the motor 3 from being installed upside down.

[0040] The volute 5 includes a lower volute 10 fixed to the mounting plate 6, and an upper volute 11 matched with the lower volute 10, and the lower volute 10 is embedded with a nut 12 for fixing the upper volute 11. By embedding the nut 12 in the lower volute 10, it is beneficial to directly fix the upper volute 11 to the lower volute 10 through the studs, so as to improve the assembly efficiency of the centrifugal fan 1 while ensuring the fastening, safety and reliability of the volute 5.

[0041] Volute reinforcement plates 13 are provided at both ends of the lower volute 10, and the installation position of the lower volute 10 is located between the reinforcement plates 13 and the mounting plate 6. The installation position of the lower volute 10 is located between the reinforcement plates 13 and the mounting plate 6, and the reinforcement plates 13 are fixed by countersunk screws and washer nuts to disperse the fastening force, prevent stress concentration, and ensure installation reliability.

[0042] The lower volute 10 is provided with a wire buckle 14 integrally formed with the lower volute 10. The wire buckle 14 is used to fix the power cord of the centrifugal fan 1, and the use of wire ties is eliminated, which can effectively eliminate the risk of wire cutting caused by fixing the general centrifugal fan on the mounting plate by wire ties, and at the same time improve the assembly efficiency of the centrifugal fan 1.

[0043] The invention fan and the general fan designed according to the above centrifugal fan parameters are now tested for relevant performance. The simulated flow fields of the general fan (left) and the invention fan (right) are compared. Figure 6As shown, the high-speed area is larger, the airflow can obtain more power through the impeller, and the blade efficiency is significantly higher than that of general centrifugal fans. The actual prototype test results are shown in Figure 7 and Figure 8 As shown, the noise level of the centrifugal fan of the present invention at each gear is 3-5dB(A) lower than that of the general centrifugal fan.

[0044] The fan assembly efficiency of the invention designed according to the above centrifugal fan related parameters is increased by 12%, after-sales failures are reduced by 50%, noise can be reduced by 3-5dB(A), and air volume is increased by 8%, thereby reducing the fan production cost and improving the fan reliability and fan performance.

[0045] Example 2

[0046] The present embodiment provides an air conditioner, which uses the low-noise and high-reliability bus air-conditioning centrifugal fan described in Example 1. By reasonably designing the length-to-width ratio of the air outlet 2 of the centrifugal fan 1, the air outlet of the centrifugal fan 1 is ensured to be more uniform, and the local vortex is reduced, thereby reducing the noise of the centrifugal fan 1, effectively improving the noise level of the centrifugal fan 1, increasing the reliability of the performance of the bus air conditioner, and thereby increasing the comfort of the bus.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A low-noise and high-reliability bus air conditioning centrifugal fan, comprising a centrifugal fan body, characterized in that: The length of the air outlet of the centrifugal fan body is L, the width of the air outlet of the centrifugal fan body is W, and the following relationship is satisfied: 2≥L / W≥1.2; the centrifugal fan body comprises a motor having two output ends, and centrifugal fan blades respectively arranged at the two output ends of the motor, and a volute arranged outside the centrifugal fan blades, and mounting plates respectively fixed to the motor and the volute, the air outlet of the centrifugal fan body is located on the mounting plate, and the air outlet of the centrifugal fan body is communicated with the inside of the volute; A guide ring is provided at one end of the volute close to the motor, the axial distance between the side of the guide ring close to the motor and the end face of the motor is d, the diameter of the centrifugal fan blade is D, d / D is x, the relative air volume is y, and the following relationship is satisfied: y=-3.2495x 2 +2.4306x+0.5709,0.3≥x>0; y=1,x>0.3; Where y is the relative air volume, which represents the ratio of the existing air volume to the ideal air volume.

2. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 1, characterized in that: d / D= x≥0.

2.

3. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 2, characterized in that: d / D=x=0.

25.

4. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 1, characterized in that: The mounting plate includes a mounting plate body, and a motor mounting boss integrally formed with the mounting plate body and located in the middle of the mounting plate body, the motor mounting boss is provided with two groups of fixing holes for fixing the motor, wherein the spacing of one group of fixing holes is a, and the spacing of the other group of fixing holes is b, and the difference between a and b is greater than 2 times the diameter of the fixing holes.

5. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 1, characterized in that: The volute comprises a lower volute fixed to the mounting plate, and an upper volute matched with the lower volute, and the lower volute is embedded with a nut for fixing the upper volute.

6. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 5, characterized in that: Volute reinforcement plates are arranged at both ends of the lower volute, and the installation position of the lower volute is located between the reinforcement plates and the installation plates.

7. A low-noise and high-reliability bus air conditioning centrifugal fan as claimed in claim 5, characterized in that: The lower volute is provided with a wire buckle which is integrally formed with the lower volute.

8. An air conditioner, characterized in that: Including the low-noise and high-reliability bus air-conditioning centrifugal fan as described in any one of claims 1 to 7.

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