air conditioner

Abstract

This invention discloses an air conditioner, comprising a casing and a heat exchanger. The casing has an air inlet and an air outlet, and the heat exchanger is disposed corresponding to the air inlet. The air conditioner further includes an axial flow fan assembly disposed between the air outlet and the heat exchanger. The axial flow fan assembly includes an air outlet duct and a rear fan blade installed inside the air outlet duct near the heat exchanger. The diameter of the air outlet duct is d0, where 250mm ≤ d0 ≤ 450mm. The minimum distance between the rear fan blade and the heat exchanger is d1, where 20mm ≤ d1 ≤ 120mm. This invention reduces the noise generated during air conditioner operation.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to an air conditioner. Background Technology

[0002] An axial flow fan assembly has one, two, or more axial flow impellers inside. For axial flow fans with two or more axial flow impellers, the air volume is larger during operation.

[0003] Some existing air conditioners are equipped with axial fan assemblies. As these axial fan assemblies themselves inevitably generate considerable noise during operation, they are not without their own drawbacks. Summary of the Invention

[0004] The main objective of this invention is to provide an air conditioner that addresses the problem of excessive noise in existing air conditioners.

[0005] To achieve the above objectives, the air conditioner proposed in this invention includes a housing and a heat exchanger. The housing has an air inlet and an air outlet, and the heat exchanger is disposed corresponding to the air inlet. The air conditioner further includes:

[0006] An axial flow fan assembly is disposed between the air outlet and the heat exchanger; the axial flow fan assembly includes an air outlet duct and a rear fan blade installed inside the air outlet duct and close to the heat exchanger. The diameter of the air outlet duct is d0, 250mm≤do≤450mm. The minimum distance between the rear fan blade and the heat exchanger is d1, 20mm≤d1≤120mm.

[0007] Preferably, 60mm≤d1≤80mm.

[0008] The air conditioner includes an indoor unit and an outdoor unit. The axial fan assembly is placed inside the indoor unit. The indoor unit can be a floor-standing unit, a ceiling-mounted unit, or a wall-mounted unit; or, the axial fan assembly is placed inside the outdoor unit.

[0009] Preferably, the axial flow fan assembly is a first fan, and a second fan is also provided inside the air conditioner. Both the first fan and the second fan are located in the indoor unit of the air conditioner, with a diameter of 30mm ≤ d4 ≤ 40mm; or...

[0010] Both the first fan and the second fan are installed in the outdoor unit of the air conditioner, with a diameter of 30mm ≤ d4 ≤ 40mm.

[0011] Preferably, the axial flow fan assembly further includes a front fan blade near the air outlet, and the distance between the front fan blade and the rear fan blade is d2, where 10mm ≤ d2 ≤ 50mm.

[0012] Preferably, 20mm≤d2≤30mm.

[0013] Preferably, the axial flow fan assembly further includes a rear motor and a rear bracket, the rear fan blade is mounted on the rear motor, the rear motor is mounted on the rear bracket, and the rear bracket is located on the rear side of the rear fan blade.

[0014] Preferably, the minimum distance between the rear support and the rear fan blade is d3, where 5mm ≤ d3 ≤ 30mm.

[0015] Preferably, 10mm≤d3≤20mm.

[0016] Preferably, the axial flow fan assembly further includes a front motor, a front fan blade, and a front bracket, wherein the front fan blade is mounted on the front motor, the front motor is mounted on the front bracket, and the front bracket is located on the front side of the front fan blade.

[0017] Preferably, the minimum distance between the front bracket and the front fan blade is d4, where 5mm≤d4≤30mm.

[0018] Preferably, 10mm≤d4≤20mm

[0019] Preferably, the axial flow fan assembly further includes an air outlet duct and a front fan blade near the air outlet. The front fan blade and the rear fan blade are disposed inside the air outlet duct. The distance between the front fan blade and / or the rear fan blade and the inner wall of the air outlet duct is d5, where 3mm≤d5≤15mm.

[0020] Preferably, 6mm≤d5≤10mm.

[0021] Preferably, the heat exchanger is a direct-flow heat exchanger, a V-type heat exchanger, a C-type heat exchanger, a U-type heat exchanger, or a W-type heat exchanger.

[0022] Preferably, the axial flow fan assembly further includes a front fan blade near the air outlet, wherein the rotation direction of the front fan blade when blowing airflow toward the air outlet is opposite to the rotation direction of the rear fan blade when blowing airflow toward the air outlet.

[0023] The technical solution of this invention limits the diameter d0 of the outlet duct of the axial flow fan assembly to a certain value.

[0024] The minimum distance d1 between the rear fan blade and the heat exchanger is limited to 20mm≤d1≤120mm, which greatly reduces the noise generated during the operation of the air conditioner. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of an embodiment of the air conditioner of the present invention;

[0027] Figure 2 for Figure 1 Front view of the central air conditioner;

[0028] Figure 3 for Figure 1 A schematic diagram of the internal structure of a central air conditioner, with the front panel removed;

[0029] Figure 4 for Figure 2 A cross-sectional view of the central air conditioner along the MM line.

[0030] Explanation of icon numbers:

[0031] label name label name 10 air conditioner 11 shell 11a Front panel 11b Back panel 110 air vent 12 Axial flow fan assembly 120 air outlet 121a Forewind blades 122a Front motor 123a Front bracket 121b Back wind leaf 122b Rear motor 123b Rear bracket 13 heat exchanger

[0032] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0035] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0036] Please see Figure 1 This invention proposes an air conditioner 10, which can be a floor-standing air conditioner, a ceiling-mounted air conditioner, etc. The following description of the air conditioner 10 uses a floor-standing indoor unit as a specific embodiment.

[0037] Please see Figure 2 , Figure 3 and Figure 4 The outer casing 11 has a front panel 11a and a back panel 11b. The front panel 11a has an air outlet 110 with an air outlet frame. The back panel 11b has an air inlet with an air inlet grille. A filter screen is installed inside the air inlet grille. The heat exchanger 13 is installed inside the outer casing 11 and located between the air inlet and the air outlet 110. Typically, the heat exchanger 13 can be installed on the back panel 11b or the side panel, but other installation methods are also possible. An axial flow fan assembly 12 is installed at the air outlet 110. When the air conditioner 10 is in cooling mode, the axial flow fan assembly 12 operates, creating a negative pressure behind it. Under this negative pressure, external air passes through the heat exchanger 13 along the air inlet and is then blown towards the front of the air conditioner 10 by the axial flow fan assembly 12.

[0038] Specifically, the axial flow fan assembly 12 can be a single-stage axial flow fan (with only one blade) or a multi-stage axial flow fan (with multiple blades, such as two, three, or even more, arranged at intervals along the axial direction of the outlet duct). For multi-stage axial flow fans, the following embodiments will specifically use a counter-rotating fan as an example. For a counter-rotating fan, a front blade and a rear blade are arranged in the outlet duct. The rotation direction of the front blade blowing airflow towards the outlet is opposite to the rotation direction of the rear blade blowing airflow towards the outlet. The axial flow fan assembly 12 includes an outlet duct 120, a front blade 121a, a front support 123a, a front motor 122a, a rear blade 121b (if the axial flow fan assembly 12 has only one blade, this blade is named the rear blade), a rear support 123b, and a rear motor 122b. The air outlet duct 120 is installed at the air outlet 110, and both ends of the air outlet duct 120 are open. The rear bracket 123b is installed inside the air outlet duct 120 and is located near its air inlet end. The rear motor 122b is installed on the rear bracket 123b. The rear fan blade 121b is located inside the air outlet duct 120 and is installed on the rear motor 122b. The front bracket 123a is installed inside the air outlet duct 120 and is located near its air outlet end. The front motor 122a is installed on the front bracket 123a. The rear fan blade 121b is located inside the air outlet duct 120 and is installed on the rear motor 122b.

[0039] The heat exchanger 13 can be straight, V-shaped, C-shaped, U-shaped, or W-shaped.

[0040] Please see Figures 1 to 4 The diameter d0 of the air outlet duct 120 is 250mm≤d0≤450mm, for example d0=280mm, 300mm, 330mm, 350mm, 380mm, 400mm, 420mm or 440mm. Of course, it is preferred here that d0∈[300mm,400mm].

[0041] The minimum distance between the rear fan blade 121b and the heat exchanger 13 is d1, where d1 ∈ [20mm, 120mm], for example, d1 = 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 110mm, etc.

[0042] To test the impact of d1 on the noise of air conditioner 10, a test was conducted using an air outlet duct 120 with a diameter of 360mm and an air volume of 1200 cubic meters as an example. The experiment is as follows:

[0043] Table 1A

[0044]

[0045]

[0046] Normally, the larger d1 is, the lower the noise of the axial fan assembly 12 at the same air volume. However, as can be seen from Table 1, when d1 is greater than 120mm, the noise change at the same air volume is not significant. From a noise perspective, d1 of 120mm is optimal. However, when d1 is too large, it will affect the thickness of the entire unit and increase the manufacturing cost. Furthermore, when d1 is greater than 60mm, the noise reduction at the same air volume decreases. Therefore, overall, d1 between 60mm and 80mm is better.

[0047] The above embodiments are for a single bipolar axial flow fan (counter-rotor fan).

[0048] In addition, tests showed that when the air conditioner contains not only a single bipolar axial fan (counter-rotating fan, referred to here as the first fan) but also other fans (referred to as the second fan), such as axial, cross-flow, or centrifugal fans, the optimal value of d1 changes. Of course, both the first and second fans can be installed in the indoor unit or both in the outdoor unit.

[0049] To test the relationship between the noise generated by two or more fans and d1, the following experiment was conducted (taking the indoor unit as an example):

[0050] Table 1B

[0051]

[0052] As can be seen from Table 1B, when d1 is between 60mm and 80mm, the noise of the indoor air conditioner unit is relatively high. On the contrary, when d1 is between 30mm and 40mm, the noise of the indoor air conditioner unit is at the lowest level. In particular, when d4 = 30mm, the noise value is at its lowest.

[0053] Besides d1 having a significant impact on the noise of the axial fan assembly 12, other parameters also have varying degrees of influence on the noise of the axial fan assembly 12. For example, the distance between the front fan blade 121a and the rear fan blade 121b is d2.

[0054] The minimum distance between the rear support 123b and the rear fan blade 121b is d3.

[0055] The minimum distance between the front support 123a and the front fan blade 121a is d4.

[0056] The distance between the front fan blade 121a and / or the rear fan blade 121b and the inner wall of the air outlet duct 120 is d5, etc.

[0057] In order to reduce the noise of the axial flow fan assembly 12 to a lower level, the above parameters were tested respectively.

[0058] To test the impact of d2 on the noise of air conditioner 10, a test was conducted using an air outlet duct 120 with a diameter of 360mm and an air volume of 1200 cubic meters as an example. The experiment is as follows:

[0059] Table 2

[0060]

[0061] As shown in Table 2, the smaller d2 is, the greater the air volume of the axial flow fan assembly 12 at the same rotational speed, and the lower the fan noise at the same air volume. However, due to assembly errors, deformation during transportation, and deformation of the fan blades under stress during operation, the distance between the two fan blades should not be too small to ensure the reliability of the fan operation. Referring to Table 2, when d2 is in the range of 10mm to 50mm, the noise is below 50dB. When d2 is in the range of 20mm to 30mm, it can satisfy the requirement of low noise and effectively prevent interference caused by excessively small spacing between the two fan blades.

[0062] To test the impact of d3 on the noise of air conditioner 10, a test was conducted using an air outlet duct 120 with a diameter of 360mm and an air volume of 1200 cubic meters as an example. The experiment is as follows:

[0063] Table 3

[0064]

[0065]

[0066] Theoretically, the smaller d3 is, the better. However, considering the assembly, transportation, and deformation of the rear fan blade 121b during operation, d3 should not be too large or too small. Therefore, a d3 between 5mm and 30mm is preferred, within which the noise level is below 50dB.

[0067] Furthermore, Table 3 shows that when d3 increases from 15mm to 20mm, the noise level suddenly drops to a lower level, and then increases again when d3 continues to rise from 20mm. This is likely because when d3 is between 5mm and 15mm, some vortices are generated between the two blades, increasing wind resistance, energy consumption, and noise. When d3 is between 15mm and 20mm, the vortex effect decreases, thus reducing noise. As d3 continues to increase, the vortex effect intensifies, leading to a greater noise level.

[0068] The minimum distance d4 between the front support 123a and the front fan blade 121a is similar to that between the rear support 123b and the rear fan blade 121b, that is, d4∈[5mm,30mm], preferably d4∈[10mm,20mm].

[0069] To test the impact of d5 on the noise of unit 10, a test was conducted using an air outlet duct 120 with a diameter of 360mm and an air volume of 1200 cubic meters as an example. The experiment is as follows:

[0070] Table 4

[0071]

[0072]

[0073] According to theoretical and test verification, the smaller d5 is, the larger the air volume of the small axial flow fan assembly 12 at the same speed, and the lower the fan noise at the same air volume. However, considering the possible errors or deformations in assembly, transportation and fan operation, in order to avoid interference between the fan blades and the inner wall of the air outlet duct 120, d5 should not be too large or too small.

[0074] Since the manufacturing tolerance of the 360mm air outlet duct 120 is ±2mm, interference can easily occur between the fan blades and the inner wall of the air outlet duct 120 when d5 = 2mm. Therefore, in this embodiment, d5 ≥ 3mm.

[0075] As can be seen from Table 4, when d5 = 15mm, the corresponding noise value is 49.8mm, which is very close to 50mm. Therefore, d5 is better in the range of 3mm to 15mm.

[0076] In addition, Table 4 also shows that the noise level increases slowly as d5 gradually increases from 2mm to 10mm, while the noise level increases rapidly when d5 increases from 8mm to 10mm. Based on this, it is preferable that 6mm≤d5≤10mm, with 7mm being the optimal value.

[0077] When the air conditioner 10 is supplying air, the rear fan blade 121b rotates counterclockwise. At this time, under the action of the rear fan blade 121b, outside air passes through the heat exchanger 13 and flows towards the front of the rear fan blade 121b. The airflow has kinetic energy in both counterclockwise rotation and axial kinetic energy along the rear fan blade 121b. If the front fan blade 121a rotates in the same direction as the rear fan blade 121b when actively supplying air forward, the airflow ultimately delivered by the front fan blade 121a will have higher rotational kinetic energy, thus resulting in a shorter air supply distance.

[0078] Therefore, in this embodiment, the rotation direction of the rear fan blade 121b when guiding the airflow from the inlet end to the outlet end is opposite to the rotation direction of the front fan blade 121a when guiding the airflow from the inlet end to the outlet end. Thus, when the airflow located between the two axial flow impellers flows out from the front fan blade 121a, most of its rotational kinetic energy is converted into axial kinetic energy, resulting in a longer air delivery distance.

[0079] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An air conditioner, comprising a housing and a heat exchanger, the housing having an air inlet and an air outlet, the heat exchanger being disposed corresponding to the air inlet, characterized in that, Also includes: An axial flow fan assembly is disposed between the air outlet and the heat exchanger; the axial flow fan assembly includes an air outlet duct and a rear fan blade installed inside the air outlet duct near the heat exchanger, the diameter of the air outlet duct is d0, 250mm≤d0≤450mm; the minimum distance between the rear fan blade and the heat exchanger is d1, 20mm≤d1≤120mm; The axial flow fan assembly also includes a rear motor and a rear support. The rear fan blade is mounted on the rear motor, and the rear motor is mounted on the rear support. The rear support is located behind the rear fan blade. The minimum distance between the rear support and the rear fan blade is d3, where 10mm ≤ d3 ≤ 18mm. The axial flow fan assembly further includes a front motor, a front fan blade, and a front bracket. The front fan blade is close to the air outlet, the front fan blade is mounted on the front motor, the front motor is mounted on the front bracket, and the front bracket is located in front of the front fan blade. The rotation direction of the front fan blade when blowing airflow towards the air outlet is opposite to the rotation direction of the rear fan blade when blowing airflow towards the air outlet. The minimum distance between the front bracket and the front fan blade is d4, where 10mm ≤ d4 ≤ 20mm. The front fan blade and the rear fan blade are disposed inside the air outlet duct, and the distance between the front fan blade and / or the rear fan blade and the inner wall of the air outlet duct is d5, where 3mm≤d5≤15mm.

2. The air conditioner as described in claim 1, characterized in that, 60mm≤d1≤80mm.

3. The air conditioner as described in claim 1, characterized in that... The air conditioner includes an indoor unit and an outdoor unit. The axial fan assembly is placed inside the indoor unit. The indoor unit can be a floor-standing unit, a ceiling-mounted unit, or a wall-mounted unit; or, the axial fan assembly is placed inside the outdoor unit.

4. The air conditioner as described in claim 1, characterized in that, The axial flow fan assembly is the first fan, and a second fan is also installed inside the air conditioner. Both the first fan and the second fan are installed in the indoor unit of the air conditioner, with a diameter of 30mm ≤ d1 ≤ 40mm; or... Both the first fan and the second fan are installed in the outdoor unit of the air conditioner, with a diameter of 30mm ≤ d1 ≤ 40mm.

5. The air conditioner as described in claim 1, characterized in that, The distance between the front wind vane and the rear wind vane is d2, where 10mm≤d2≤50mm.

6. The air conditioner as described in claim 5, characterized in that, 20mm≤d2≤30mm.

7. The air conditioner as described in claim 1, characterized in that, 6mm≤d5≤10mm.

8. The air conditioner as described in claim 1, characterized in that, The heat exchanger is a direct-flow heat exchanger, a V-type heat exchanger, a C-type heat exchanger, a U-type heat exchanger, or a W-type heat exchanger.

Images