A guide ring structure, axial flow fan, outdoor unit and air conditioning system

Abstract

The present invention discloses a guide ring structure, an axial flow fan, an outdoor unit and an air-conditioning system, which relate to the field of air-conditioning and solve the technical problem that various vortices formed inside the axial flow fan in the prior art not only generate aerodynamic noise but also cause air volume loss of the fan. The guide ring structure of the present invention comprises a guide ring body and a fixed wing assembly, wherein the guide ring body is used to install the fan blade, the fixed wing assembly is arranged in the guide ring body, and the fixed wing assembly is located at the trailing edge of the fan blade. The guide ring structure of the present invention can disperse the shedding vortex generated at the trailing edge of the fan blade and the phase vortex generated between adjacent fan blades through the action of the fixed wing, thereby not only reducing the aerodynamic noise of the fan, but also reducing the air volume loss of the fan, thereby achieving the purpose of increasing the air volume and improving the performance of the fan.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to a guide ring structure, an axial flow fan, an outdoor unit and an air conditioning system. Background Art

[0002] In air conditioner outdoor units, aerodynamic noise from axial fans is second only to compressor vibration noise as a significant source of noise. Therefore, optimizing and improving the axial fan blades and guide rings is a key design task to improve aerodynamic noise. Axial fan aerodynamic noise is generated by the following: Various complex vortices easily form within the impeller of the axial fan blades, such as shedding vortices formed by the boundary layer shedding on the suction surface of the blades and phase vortices formed by the periodic motion of adjacent blades. These vortices destabilize the airflow within the duct, generating turbulent aerodynamic noise.

[0003] The applicant also found that: axial flow blades with different installation angles form trailing edge vortices in different directions, and the noise forms vary greatly. Specifically, for axial flow blades with large installation angles, the trailing edge vortices easily overflow the closed fan guide ring structure, resulting in vortex noise; for axial flow blades with small installation angles, interference vortices are easily formed between phases, resulting in rotational noise that cannot be effectively controlled. On the other hand, the various vortices formed inside the impeller of the axial flow blade not only generate aerodynamic noise, but also cause air volume loss of the fan, affecting the performance of the fan. Existing axial flow fans have the problem of difficulty in increasing air volume. Specifically, axial flow blades with large attack angles have low efficiency and cannot achieve high air volume under energy consumption requirements. For axial flow blades with small attack angles, the transfer frequency required to increase air volume is too high, and the high-speed operation of the blades can easily lead to their strength failure.

[0004] The prior art discloses a guide ring structure, an axial flow fan, and an air conditioner. The guide ring structure comprises a ring body, which includes a closed cavity and a through hole. An opening is provided at the smallest diameter of the ring body, connecting the cavity with the through hole, allowing fluid within the through hole to enter the cavity. The guide ring structure also includes an internal groove to increase the gap between the ring body and the fan blades. While this solution achieves noise reduction, it still presents the following issues: The gap at the blade tip allows downstream high-speed airflow to flow back upstream through the blade tip gap, reducing effective airflow. Furthermore, the blade tip vortex diffuses downstream, exacerbating downstream noise. Summary of the Invention

[0005] One of the objectives of the present invention is to provide a guide ring structure that addresses the technical problem of various vortices formed within axial flow fans in the prior art, which not only generate aerodynamic noise but also cause airflow loss. The various technical benefits of the preferred technical solution of the present invention are detailed below.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] The guide ring structure of the present invention comprises a guide ring body and a fixed wing assembly, wherein the guide ring body is used to install a fan blade, the fixed wing assembly is arranged in the guide ring body, and the fixed wing assembly is located at the trailing edge of the fan blade.

[0008] According to a preferred embodiment, the fixed wing assembly includes a plurality of fixed wings, the fixed wings are evenly distributed along the circumferential direction of the guide ring body, and the inclination direction of the fixed wings is consistent with the inclination direction of the wind blades.

[0009] According to a preferred embodiment, the inclination angle of the fixed wing is determined by the installation angle of the wind blade.

[0010] According to a preferred embodiment, when the installation angle of the fan blade is 28-35°, the installation angle of the fixed wing is 37-42°; when the installation angle of the fan blade is 35-45°, the installation angle of the fixed wing is 30-37°.

[0011] According to a preferred embodiment, the fixed wing is a concave arc structure, and the concave surface of the fixed wing is located on the windward side of the fan blade.

[0012] According to a preferred embodiment, the fixed wing is provided with an opening, and the opening is arranged on the windward surface of the fixed wing.

[0013] According to a preferred embodiment, the diameter of the opening satisfies: 1mm≤D≤2mm, and the spacing between two adjacent openings satisfies: D≤L≤1.5D, wherein D is the diameter of the opening and L is the spacing between two adjacent openings.

[0014] According to a preferred embodiment, the depth of the opening is less than the thickness of the fixed wing, and the depth of the opening also satisfies: 1.5D≤H≤2.5D, wherein D is the diameter of the opening and H is the depth of the opening.

[0015] According to a preferred embodiment, the angle between the direction of the opening and the air outlet direction of the fan satisfies: 20°≤α≤30°, wherein α is the angle between the direction of the opening and the air outlet direction of the fan.

[0016] According to a preferred embodiment, the number of the fixed wings is (M×N), wherein M is an integer greater than the number of the wind blades, and N is an integer greater than or equal to 1.

[0017] According to a preferred embodiment, the fixed wing is rotatably arranged on the guide ring body.

[0018] According to a preferred embodiment, the fixed wing assembly further includes a connecting rod and a driving member, wherein the connecting rod is connected to the driving member, one end of the fixed wing is connected to the connecting rod via a first rotating shaft mounted on the connecting rod, and the fixed wing is further connected to the deflector body via a second rotating shaft. The deflector structure provided by the present invention has at least the following beneficial technical effects:

[0019] The guide ring structure of the present invention includes a guide ring body and a fixed wing assembly. The guide ring body is used to mount the fan blades, and the fixed wing assembly is arranged within the guide ring body and is located at the trailing edge of the fan blade. The fixed wing assembly can disperse the shedding vortex generated by the trailing edge of the fan blade and the phase vortex generated between adjacent fan blades through the action of the fixed wing, thereby not only reducing the aerodynamic noise of the fan but also reducing the fan's air volume loss, thereby achieving the purpose of increasing air volume and improving fan performance. In other words, the guide ring structure of the present invention solves the technical problem of various vortices formed inside axial flow fans in the prior art, which not only generate aerodynamic noise but also cause fan air volume loss.

[0020] A second object of the present invention is to provide an axial flow fan.

[0021] The axial flow fan of the present invention comprises a fan body and a guide ring structure, wherein the guide ring structure is the guide ring structure described in any technical solution of the present invention.

[0022] The axial flow fan provided by the present invention has at least the following beneficial technical effects:

[0023] The axial flow fan of the present invention includes the guide ring structure of any technical solution in the present invention. Through the function of the guide ring structure, not only the aerodynamic noise of the fan can be reduced, but also the air volume loss of the fan can be reduced, thereby achieving the purpose of increasing the air volume and improving the performance of the fan.

[0024] A third object of the present invention is to provide an outdoor unit.

[0025] The outdoor unit of the present invention comprises an outdoor unit body and an axial flow fan, wherein the axial flow fan is the axial flow fan described in any technical solution of the present invention.

[0026] The outdoor unit of the present invention includes the axial flow fan of any one of the technical solutions of the present invention. Since the aerodynamic noise of the axial flow fan is reduced and the air volume is increased, the performance of the outdoor unit can be improved.

[0027] A fourth object of the present invention is to provide an air conditioning system.

[0028] The air conditioning system of the present invention comprises an indoor unit and an outdoor unit, wherein the indoor unit is connected to the outdoor unit, and the outdoor unit is the outdoor unit described in any one of the technical solutions of the present invention.

[0029] The air conditioning system of the present invention includes the outdoor unit of any one of the technical solutions of the present invention. Since the performance of the outdoor unit is improved, the performance of the air conditioning system can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 Schematic diagram of a preferred embodiment of the axial flow fan of the present invention;

[0032] Figure 2 It is a partial schematic diagram of a preferred embodiment of the axial flow fan of the present invention;

[0033] Figure 3 is a schematic diagram of the connection between the fixed wing and the connecting rod of the present invention;

[0034] Figure 4 This is a first schematic diagram of the fixed wing tilt angle and the fan blade installation angle of the present invention;

[0035] Figure 5 This is a second schematic diagram of the fixed wing tilt angle and the fan blade installation angle of the present invention;

[0036] Figure 6 Schematic diagram of a preferred embodiment of the fixed-wing aircraft of the present invention;

[0037] Figure 7 It is a partial schematic diagram of a preferred embodiment of the fixed-wing aircraft of the present invention.

[0038] In the figure: 1. guide ring body; 2. fan blade; 3. fixed wing; 31. opening; 4. connecting rod; 5. first rotating shaft; 6. second rotating shaft. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0040] The following is attached with the instruction manual Figures 1 to 7 And embodiments 1 to 4 describe the guide ring structure, axial flow fan, outdoor unit and air conditioning system of the present invention in detail.

[0041] Example 1

[0042] This embodiment describes the guide ring structure of the present invention in detail.

[0043] The guide ring structure of this embodiment includes a guide ring body 1 and a fixed wing assembly, such as Figure 1 As shown. Preferably, the guide ring body 1 is used to install the fan blade 2. Preferably, the fixed wing assembly is arranged in the guide ring body 1, and the fixed wing assembly is located at the trailing edge of the fan blade 2, as shown. Figure 1 or Figure 2 As shown. The trailing edge of the fan blade 2 mentioned in this embodiment refers to the end of the fan blade 2 opposite to its fixed end. More preferably, the guide ring body 1 is the same as the closed guide ring structure in the prior art, which will not be repeated here. The guide ring structure of this embodiment can disperse the shedding vortex generated by the trailing edge of the fan blade and the phase vortex generated between adjacent fan blades through the action of the fixed wing, thereby not only reducing the aerodynamic noise of the fan, but also reducing the wind volume loss of the fan, thereby achieving the purpose of increasing the wind volume and improving the performance of the fan. That is, the guide ring structure of this embodiment solves the technical problem that various vortices formed inside the axial flow fan in the prior art not only generate aerodynamic noise but also cause wind volume loss of the fan.

[0044] According to a preferred embodiment, the fixed wing assembly includes a plurality of fixed wings 3, the fixed wings 3 are evenly distributed along the circumferential direction of the guide ring body 1, and the inclination direction of the fixed wings 3 is consistent with the inclination direction of the wind blade 2, such as Figure 1 or Figure 2 As shown in the figure, the guide ring structure of the preferred technical solution of this embodiment has fixed wings 3 evenly distributed along the circumferential direction of the guide ring body 1, and the inclination direction of the fixed wings 3 is consistent with the inclination direction of the fan blades 2. The fixed wings 3 can effectively guide the airflow along the wall surface of the guide ring body 1, thereby dispersing the shedding vortex generated by the trailing edge of the fan blade and the phase vortex generated between adjacent fan blades, thereby reducing the aerodynamic noise of the fan and reducing the fan's air volume loss, thereby achieving the purpose of increasing air volume and improving fan performance.

[0045] According to a preferred embodiment, the inclination angle of the fixed wing 3 is determined by the installation angle of the fan blade 2. Preferably, when the installation angle of the fan blade 2 is 28-35 degrees, the installation angle of the fixed wing 3 is 37-42 degrees; when the installation angle of the fan blade 2 is 35-45 degrees, the installation angle of the fixed wing 3 is 30-37 degrees. The installation angle of the fan blade 2 and the inclination angle of the fixed wing 3 are relative to the horizontal plane, such as Figure 4 and Figure 5As shown in the figure, in the guide ring structure of the preferred technical solution of this embodiment, when the installation angle of the fan blades 2 is small, the air duct resistance is large, and interference vortices are generated in the channels between adjacent fan blades 2. In this case, the installation angle of the fixed wings 3 is large, so that the fixed wings 3 can effectively guide the airflow to be discharged, thereby effectively dispersing the phase vortex and effectively reducing the impact of the phase vortex on the fan. When the installation angle of the fan blades 2 is large, the blade tip shedding vortex is easily discharged directly and expanded into a large-scale vortex. In this case, the installation angle of the fixed wings 3 is small, so that the fixed wings 3 can guide the shedding vortex to dissipate on the inner wall surface of the guide ring body 1, thereby effectively dispersing the shedding vortex and effectively reducing the impact of the shedding vortex on the fan.

[0046] According to a preferred embodiment, the fixed wing 3 is a concave arc structure, and the concave surface of the fixed wing 3 is located on the windward side of the fan blade 2, such as Figure 1 or Figure 2 As shown in the figure, the guide ring structure of the preferred technical solution of this embodiment has a concave arc-shaped fixed wing 3, and the concave surface of the fixed wing 3 is located on the windward side of the fan blade 2. This can further enable the fixed wing 3 to effectively guide the airflow to move along the wall surface of the guide ring body 1, thereby further dispersing the shedding vortex generated by the trailing edge of the fan blade and the phase vortex generated between adjacent fan blades, thereby further reducing the aerodynamic noise of the fan and further reducing the wind volume loss of the fan, thereby achieving the purpose of increasing the wind volume and improving the fan performance.

[0047] According to a preferred embodiment, the fixed wing 3 is provided with an opening 31, and the opening 31 is arranged on the windward side of the fixed wing 3, such as Figure 6 or Figure 7 As shown. Preferably, the openings 31 are arranged on the windward surface of the entire fixed wing 3. In the preferred technical solution of the guide ring structure of this embodiment, the openings 31 are provided on the fixed wing 3. The openings 31 not only enhance the friction loss of sound waves but also reduce the turbulence intensity at the outlet section of the guide ring body 1, thereby further reducing the aerodynamic noise of the fan and further reducing the fan's air volume loss, thereby achieving the purpose of increasing air volume and improving fan performance.

[0048] Preferably, the diameter of the opening 31 satisfies: 1 mm ≤ D ≤ 2 mm, and the spacing between two adjacent openings 31 satisfies: D ≤ L ≤ 1.5D, wherein D is the diameter of the opening 31, and L is the spacing between two adjacent openings 31. Figure 7 The guide ring structure of the preferred technical solution of this embodiment can achieve the best effect of reducing the aerodynamic noise of the fan and reducing the air volume loss by limiting the diameter of the openings 31 and the distance between two adjacent openings 31.

[0049] Preferably, the depth of the opening 31 is less than the thickness of the fixed wing 3, and the depth of the opening 31 also satisfies: 1.5D≤H≤2.5D, where D is the diameter of the opening 31 and H is the depth of the opening 31. Figure 7 The guide ring structure of the preferred technical solution of this embodiment, by limiting the depth of the opening 31, can not only make the opening 31 meet the purpose of reducing the aerodynamic noise of the fan and reducing the air volume loss, but also prevent the opening 31 from being too deep and affecting the strength of the fixed wing 3.

[0050] Preferably, the angle between the direction of the opening 31 and the air outlet direction of the fan satisfies: 20°≤α≤30°, where α is the angle between the direction of the opening 31 and the air outlet direction of the fan, such as Figure 6 The guide ring structure of the preferred technical solution of this embodiment can achieve the best effect of reducing the aerodynamic noise of the fan and reducing the air volume loss by limiting the angle of the opening 31.

[0051] According to a preferred embodiment, the number of fixed wings 3 is (M×N), wherein M is an integer greater than the number of fan blades 2, and N is an integer greater than or equal to 1. Preferably, the value of N is 2, 3 or 4. The value of N can also be selected according to actual conditions. The number of fan blades 2 is generally 3 to 5. For example, when the number of fan blades 2 is 3, the number of fixed wings 3 is 4N; when the number of fan blades 2 is 4, the number of fixed wings 3 is 5N; when the number of fan blades 2 is 5, the number of fixed wings 3 is 6N. The guide ring structure of the preferred technical solution of this embodiment, by limiting the number of fixed wings 3, can not only avoid the problem of increased wind resistance and excessive wind volume attenuation due to too many fixed wings 3, but also avoid the problem of unclear guide effect and noise reduction effect due to too few fixed wings 3.

[0052] According to a preferred embodiment, the fixed wings 3 are rotatably mounted on the guide ring body 1. Specifically, the mounting angle of the fixed wings 3 can be adjusted manually or automatically. The guide ring structure of this preferred technical solution, in which the fixed wings 3 are rotatably mounted on the guide ring body 1, can be adjusted to accommodate axial flow fans with blades at different mounting angles, thereby enhancing its applicability.

[0053] According to a preferred embodiment, the fixed wing assembly further comprises a connecting rod 4 and a driving member, such as Figure 2 and Figure 3 Preferably, the connecting rod 4 is connected to the driving member, one end of the fixed wing 3 is connected to the connecting rod 4 through a first rotating shaft 5 installed on the connecting rod 4, and the fixed wing 3 is also connected to the guide ring body 1 through a second rotating shaft 6, as shown. Figure 3 As shown. Preferably, the driving member is, for example, a micro drive motor, which is not shown in the figure. Preferably, a mounting hole is provided on the connecting rod 4, the first rotating shaft 5 is installed in the mounting hole, and both ends of the first rotating shaft 5 are connected to the fixed wing 3, as shown in FIG. Figure 3Specifically, when the driver drives the connecting rod 4 clockwise, the installation angle of the fixed wing 3 increases; when the driver drives the connecting rod 4 counterclockwise, the installation angle of the fixed wing 3 decreases. The guide ring structure of the preferred technical solution of this embodiment, by mounting the fixed wing 3 on the connecting rod 4, can make the change angle of each fixed wing 3 the same through the rotation of the connecting rod 4, thereby ensuring the consistency of the installation angle of each fixed wing 3.

[0054] Example 2

[0055] This embodiment describes the axial flow fan of the present invention in detail.

[0056] The axial flow fan of this embodiment includes a fan body and a guide ring structure. Preferably, the guide ring structure is the guide ring structure of any technical solution in Example 1. The fan body is the portion of the axial flow fan excluding the guide ring. The structure of the fan body can be the same as that of the prior art and will not be further described here.

[0057] The axial flow fan of this embodiment includes the guide ring structure of any one of the technical solutions in Example 1. Through the action of the guide ring structure, not only the aerodynamic noise of the fan can be reduced, but also the air volume loss of the fan can be reduced, thereby achieving the purpose of increasing the air volume and improving the performance of the fan.

[0058] Example 3

[0059] This embodiment describes the outdoor unit of the present invention in detail.

[0060] The outdoor unit of this embodiment includes an outdoor unit body and an axial flow fan. Preferably, the axial flow fan is the axial flow fan of any of the technical solutions in Example 2. The outdoor unit body is the portion of the outdoor unit excluding the axial flow fan. The structure of the outdoor unit body can be the same as that of the prior art and will not be further described here.

[0061] The outdoor unit of this embodiment includes the axial flow fan of any one of the technical solutions in Example 2. Since the aerodynamic noise of the axial flow fan is reduced and the air volume is increased, the performance of the outdoor unit can be improved.

[0062] Example 4

[0063] This embodiment describes the air conditioning system of the present invention in detail.

[0064] The air conditioning system of this embodiment includes an indoor unit and an outdoor unit, wherein the indoor unit is connected to the outdoor unit. Preferably, the outdoor unit is the outdoor unit of any one of the technical solutions in Example 3. The structure of the indoor unit can be the same as that of the prior art and will not be described in detail here.

[0065] The air conditioning system of this embodiment includes the outdoor unit of any one of the technical solutions in Example 3. Since the performance of the outdoor unit is improved, the performance of the air conditioning system can be improved.

[0066] In the description of the present invention, it should be noted that, unless otherwise specified, "plurality" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are intended only to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0067] It should also be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; and direct or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention depending on the specific circumstances.

[0068] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A guide ring structure, characterized in that: It comprises a guide ring body (1) and a fixed wing assembly, wherein the guide ring body (1) is used to install a fan blade (2), the fixed wing assembly is arranged in the guide ring body (1), and the fixed wing assembly is located at the trailing edge of the fan blade (2); The fixed wing assembly comprises a plurality of fixed wings (3), each of the fixed wings (3) being provided with an opening (31), and the opening (31) being arranged on a windward surface of the fixed wing (3); The depth of the opening (31) is less than the thickness of the fixed wing (3), and the depth of the opening (31) also satisfies: 1.5D≤H≤2.5D, wherein D is the diameter of the opening (31) and H is the depth of the opening (31); The angle between the direction of the opening (31) and the air outlet direction of the fan satisfies: 20°≤α≤30°, wherein α is the angle between the direction of the opening (31) and the air outlet direction of the fan.

2. The guide ring structure according to claim 1, characterized in that: The fixed wings (3) are evenly distributed along the circumferential direction of the guide ring body (1), and the inclination direction of the fixed wings (3) is consistent with the inclination direction of the wind blades (2).

3. The guide ring structure according to claim 2, characterized in that: The inclination angle of the fixed wing (3) is determined by the installation angle of the fan blade (2).

4. The guide ring structure according to claim 3, characterized in that: When the installation angle of the fan blade (2) is 28-35°, the installation angle of the fixed wing (3) is 37-42°; when the installation angle of the fan blade (2) is 35-45°, the installation angle of the fixed wing (3) is 30-37°.

5. The guide ring structure according to any one of claims 2 to 4, characterized in that: The fixed wing (3) is a concave arc surface structure, and the concave surface of the fixed wing (3) is located on the windward side of the fan blade (2).

6. The guide ring structure according to claim 5, characterized in that: The diameter of the opening (31) satisfies: 1 mm ≤ D ≤ 2 mm, and the spacing between two adjacent openings (31) satisfies: D ≤ L ≤ 1.5D, wherein D is the diameter of the opening (31) and L is the spacing between two adjacent openings (31).

7. The guide ring structure according to claim 1, characterized in that: The number of the fixed wings (3) is M×N, wherein M is an integer greater than the number of the wind blades (2), and N is an integer greater than or equal to 1.

8. The guide ring structure according to claim 1, characterized in that: The fixed wing (3) is rotatably arranged on the guide ring body (1).

9. The guide ring structure according to claim 8, characterized in that: The fixed wing assembly further comprises a connecting rod (4) and a driving member, wherein the connecting rod (4) is connected to the driving member, one end of the fixed wing (3) is connected to the connecting rod (4) via a first rotating shaft (5) mounted on the connecting rod (4), and the fixed wing (3) is further connected to the guide ring body (1) via a second rotating shaft (6).

10. An axial flow fan, characterized in that: It comprises a fan body and a guide ring structure, wherein the guide ring structure is the guide ring structure according to any one of claims 1 to 9.

11. An outdoor unit, characterized in that: It comprises an outdoor unit body and an axial flow fan, wherein the axial flow fan is the axial flow fan according to claim 10.

12. An air conditioning system, characterized in that: The invention comprises an indoor unit and an outdoor unit, wherein the indoor unit is connected to the outdoor unit, and the outdoor unit is the outdoor unit according to claim 11.

Images