Fan unit and outdoor unit

Abstract

The fan unit (20) includes an axial fan (30) and a bell (40). The axial fan (30) has a hub (31) on which a rotating shaft (12a) is mounted; and blades (32) disposed on the hub (31). The axial fan (30) has a turbulent interference section (50). The turbulent interference section (50) has an overlapping section (51), which is the portion where the blades (32) and the bell (40) overlap radially in the axial direction of the axial fan (30); and an extension section (52), which is disposed on both sides of the overlapping section (51) axially in the axial direction of the axial fan (30). The axial length (h) of the extension section (52) is less than 0.1 times the radius (R) of the axial fan (30). Within the range of the turbulent interference section (50), a porous portion (61) is provided on the blade (32). The area of ​​the porous part (61) is less than 30% of the area of ​​the blade (32).

Description

Technical Field

[0001] This disclosure relates to fan units and outdoor units. Background Technology

[0002] The axial fan disclosed in Patent Document 1 has a porous component. By incorporating a porous component, the axial fan in Patent Document 1 can suppress pressure fluctuations and noise generation.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 2754862 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] There is room for improvement in axial fans or flare nozzles to reduce wind noise.

[0008] The purpose of this disclosure is to provide a fan unit that can appropriately reduce wind noise.

[0009] Methods for solving problems

[0010] The first viewpoint for solving this problem relates to a fan unit comprising an axial fan and a bell mouth. The axial fan includes: a hub on which a rotating shaft is mounted; and blades disposed on the hub. The axial fan has a turbulent interference portion, which includes: an overlapping portion, which is the portion where the blades and the bell mouth overlap radially in the axial direction of the axial fan; and an extension portion, which is disposed on both sides of the overlapping portion axially in the axial direction of the axial fan. The length of the extension portion axially is less than 0.1 times the radius of the axial fan. Within the range of the turbulent interference portion, a porous portion is provided on the blade, the area of ​​which is less than 30% of the area of ​​the blade.

[0011] According to this structure, by incorporating a porous section in the turbulence interference zone of the axial fan, turbulence can easily pass through the porous section when pressure changes occur in the air between the flare and the axial fan. This allows for an appropriate reduction in wind noise caused by surface eddies.

[0012] In the fan unit of the second viewpoint, the area of ​​the porous part is less than 25% of the area of ​​the blade.

[0013] According to this structure, by incorporating a porous section in the turbulence interference zone of the axial fan, turbulence can more easily permeate through the porous section when pressure changes occur in the air between the flare and the axial fan. This allows for a more appropriate reduction in wind noise caused by surface eddies.

[0014] In a fan unit of the third viewpoint, in a fan unit of the first or second viewpoint, the blade has: a leading edge located in front of the rotating axis in the direction of rotation; and a trailing edge located behind the rotating axis in the direction of rotation. If the dimension from the leading edge to the trailing edge is set as a first dimension, the porous portion is located at a position at least 40% of the first dimension behind the leading edge.

[0015] According to this structure, by providing a porous part at a position that is more than 40% of the first dimension rearward from the leading edge, it is possible to reduce the noise generated on the trailing edge side of the blade.

[0016] In the fan unit of the fourth viewpoint, in any of the fan units described in the first to third viewpoints, the porous portion is disposed radially in the blades up to 70% of the radius from the rotation axis to the radius of the axial fan.

[0017] According to this structure, by arranging a porous part from the rotating shaft to 70% of the radius of the axial fan, the noise generated on the trailing edge side of the blades can be reduced.

[0018] In the fan unit of the fifth viewpoint, in any of the fan units described in the first to fourth viewpoints, the blade has a trailing edge located in the rotational direction of the rotating shaft, and a notch is provided on the trailing edge. The porous material portion is provided in the portion of the blade that is closer to the rotating shaft in the radial direction than the notch.

[0019] According to this structure, by arranging a porous part in the radial direction closer to the rotation axis than the notch, it is possible to reduce the noise generated on the trailing edge side of the blade.

[0020] In the fan unit of the sixth viewpoint, in any of the fan units described in the first to fifth viewpoints, the porous part has pores with an average pore diameter of less than 1000 μm that are connected in the thickness direction of the blade.

[0021] According to this structure, when pressure changes occur, air near the surface of the blades or near the surface of the flared end is allowed to pass through the porous section, while excess air is suppressed from passing through the porous section. This reduces air loss through the axial fan.

[0022] In the fan unit of the seventh viewpoint, in any of the fan units of the first to sixth viewpoints, the flared opening has the overlapping portion, and within the range of the overlapping portion, the porous portion is provided in the flared opening, the porous portion being discontinuously arranged in the circumferential direction of the flared opening.

[0023] According to this structure, by intermittently providing a porous section in the turbulence interference section of the horn opening, turbulence can easily pass through the porous section when pressure changes occur in the air between the horn opening and the axial fan. This allows for an appropriate reduction in wind noise caused by surface eddies.

[0024] The outdoor unit of the eighth viewpoint that solves the above-mentioned problem has a fan unit based on any one of the first to seventh viewpoints.

[0025] According to this structure, when pressure changes occur in the air passing between the flared end and the axial fan, turbulence easily permeates the porous section. Therefore, the outdoor unit can appropriately reduce wind noise caused by surface eddies.

[0026] The ninth viewpoint for solving the above-mentioned problem includes a fan unit comprising an axial fan and a flared nozzle. The axial fan has a hub on which a rotating shaft is mounted; and blades disposed on the hub. The axial fan and the flared nozzle have turbulent interference portions. The turbulent interference portions have an overlapping portion, which is the portion where the blades and the flared nozzle overlap radially with respect to the axial fan; and an extension portion disposed on both sides of the overlapping portion axially with respect to the axial fan. The length of the extension portion axially is less than 0.1 times the radius of the axial fan. Within the range of the turbulent interference portions, a pressure variation component permeation portion is provided on the blades or the flared nozzle. The pressure variation component permeation portion is configured to reduce the pressure variation generated between the axial fan and the flared nozzle.

[0027] According to this structure, by providing a pressure variation component permeation section in the turbulence interference section of the axial fan or the horn nozzle, turbulence easily passes through the pressure variation component permeation section when pressure variations occur in the air passing between the horn nozzle and the axial fan. This allows for an appropriate reduction in wind noise caused by surface eddies.

[0028] In the fan unit of the tenth viewpoint, in the fan unit of the ninth viewpoint, the blade has: a leading edge located in front of the rotation direction of the rotation axis; and a trailing edge located behind the rotation direction of the rotation axis. Within the range of the turbulence interference portion, when the blade is provided with the pressure variation component permeation portion, the pressure variation component permeation portion includes a porous portion. If the dimension from the leading edge to the trailing edge is set as a first dimension, the porous portion is located at a position that is more than 40% of the first dimension from the leading edge to the rear.

[0029] According to this structure, by providing a porous part at a position that is more than 40% of the first dimension rearward from the leading edge, it is possible to reduce the noise generated on the trailing edge side of the blade.

[0030] The eleventh aspect of the solution to the aforementioned problem includes an axial fan and a bell. The axial fan has: a hub with a rotating shaft mounted on it; and blades disposed on the hub. The axial fan and the bell have a turbulent interference portion. The turbulent interference portion has: an overlapping portion, which is the portion where the blades and the bell overlap radially with respect to the axial fan; and an extension portion, which is disposed on both sides of the overlapping portion axially with respect to the axial fan. The length of the extension portion axially is less than 0.1 times the radius of the axial fan wheel, within the range of the turbulent interference portion. Inside, a pressure variation component permeation section is provided on the blade and the flare. The pressure variation component permeation section is configured to reduce the pressure variation generated between the axial flow impeller and the flare. The blade has: a leading edge located in front of the rotation direction of the rotation axis; and a trailing edge located behind the rotation direction of the rotation axis. The pressure variation component permeation section provided on the blade includes a porous portion. If the dimension from the leading edge to the trailing edge is defined as a first dimension, the porous portion is located at a position that extends at least 40% of the first dimension backward from the leading edge.

[0031] According to this structure, by providing a pressure variation component permeation section at the turbulence interference section of the axial fan and the horn, turbulence easily passes through the pressure variation component permeation section when pressure variations occur in the air passing between the horn and the axial fan. This allows for an appropriate reduction in wind noise caused by surface eddies.

[0032] In the fan unit of the twelfth viewpoint, in the fan unit of the tenth or eleventh viewpoint, the porous material portion is disposed radially in the blade up to 70% of the radius from the rotation axis to the axial fan.

[0033] According to this structure, by arranging a porous part in the blade at a position that extends more than 40% of the first dimension from the leading edge and up to 70% of the radius from the rotating axis to the axial fan, it is possible to reduce the noise generated on the trailing edge side of the blade.

[0034] In the fan unit of any of the tenth to twelfth viewpoints, when a notch is provided at the trailing edge, the porous portion is provided in the portion of the blade that is closer to the rotation axis in the radial direction than the notch.

[0035] According to this structure, by arranging a porous part in the radial direction closer to the rotation axis than the notch, it is possible to reduce the noise generated on the trailing edge side of the blade.

[0036] In the fan unit of the fourteenth viewpoint, in any of the fan units of the tenth to thirteenth viewpoints, the area of ​​the porous part is less than 30% of the area of ​​the blade.

[0037] According to this structure, compared with the case where porous parts are set over a large area of ​​the blade, the reduction in blade strength can be suppressed.

[0038] In the fan units of the ninth to fourteenth viewpoints, the pressure variation component permeation section of the fifteenth viewpoint has pores with an average pore diameter of 1000 μm or less that are connected in the thickness direction of the blade or the flare.

[0039] According to this structure, when pressure fluctuations occur, air near the surface of the blades or near the surface of the flared end is allowed to pass through the pressure fluctuation component permeator, while excess air is suppressed from passing through the pressure fluctuation component permeator. This reduces air loss through the axial fan.

[0040] In the fan units of the 9th, 10th, and 12th to 15th viewpoints, within the range of the turbulence interference section, when the pressure variation component permeation section is provided at the horn opening, the pressure variation component permeation section is intermittently arranged in the circumferential direction of the horn opening.

[0041] According to this structure, compared with the case where pressure variation component permeation portions are continuously provided in the circumferential direction of the flared mouth, the reduction in the strength of the flared mouth can be suppressed.

[0042] The outdoor unit of the seventeenth viewpoint that solves the above-mentioned problem has fan units of the ninth to sixteenth viewpoints.

[0043] According to this structure, when the air pressure changes between the horn and the axial fan, turbulence can easily pass through the pressure-changing component permeator, thus appropriately reducing wind noise caused by surface eddies. Attached Figure Description

[0044] Figure 1 This is a schematic front view showing the interior of an outdoor unit equipped with a fan unit.

[0045] Figure 2 It is a schematic representation Figure 1 A partial cross-sectional view of the fan unit.

[0046] Figure 3 yes Figure 2 A three-dimensional view of the flared mouth.

[0047] Figure 4 Viewed from the positive pressure side Figure 2 Front view of an axial fan.

[0048] Figure 5 yes Figure 4 A cross-sectional view of the blade at line D5-D5.

[0049] Figure 6 yes Figure 4 An enlarged view of an axial fan.

[0050] Figure 7 It is a graph showing the magnitude of the low-noise effect relative to the ratio of the extension length to the radius of the axial fan.

[0051] Figure 8 This is a graph showing the magnitude of the low-noise effect relative to the placement of the porous part in the blade.

[0052] Figure 9 This is a front view of the axial fan of the second embodiment as viewed from the positive pressure side.

[0053] Figure 10 This is an enlarged view of the blade in the second embodiment.

[0054] Figure 11 This is a partial cross-sectional view schematically illustrating the fan unit of the third embodiment.

[0055] Figure 12 This is a front view of the axial fan of the third embodiment as viewed from the positive pressure side.

[0056] Figure 13 This is a graph showing the magnitude of the low-noise effect in the axial fan of the third embodiment relative to the ratio of the length from the upstream end of the horn to the third end to the length of the first extension.

[0057] Figure 14 It is a graph showing the magnitude of the maximum stress on the blade relative to the ratio of the area of ​​the porous part to the area of ​​the blade. Detailed Implementation

[0058] <First Implementation>

[0059] Reference Figures 1 to 6 The first embodiment of the fan unit is described.

[0060] <Outdoor unit>

[0061] Reference Figure 1 and Figure 2The outdoor unit 10 will be described below. The outdoor unit 10 of this embodiment is the outdoor unit of an air conditioner that cools or heats the space inside a residence. The outdoor unit 10 is connected to the indoor unit via refrigerant piping. The outdoor unit 10 includes a fan unit 20 and a housing 11. The shape of the housing 11 is not particularly limited. The housing 11 may be, for example, a horizontally elongated cuboid shape. The fan unit 20 is housed within the housing 11.

[0062] <Fan Unit>

[0063] The fan unit 20 includes an axial fan 30 and a flare 40. The flare 40 is provided at the outlet 11a of the housing 11. The flare 40 is arranged around the axial fan 30 in a manner that surrounds the axial fan 30. The axial fan 30 is connected to the rotation shaft 12a of the axial fan motor 12. The axial fan motor 12 is provided in the housing 11.

[0064] The fan unit 20 is configured such that air drawn in from the intake port (not shown) of the housing 11 is blown out from the outlet 11a of the housing 11. The fan unit 20 is used, for example, as an air supply device.

[0065] <French-shaped opening>

[0066] like Figures 1 to 3 As shown, the flare 40 is housed within the housing 11 in a manner that allows it to be installed around the periphery of the outlet 11a of the housing 11. The flare 40 has a peripheral wall 41 that forms an annular shape when viewed from the front. The peripheral wall 41 has an outlet portion 42, a cylindrical portion 43, and an intake portion 44. In the following description of this embodiment, the upstream side is the upstream side of the airflow generated by the axial fan 30, and the downstream side is the downstream side of the airflow generated by the axial fan 30.

[0067] The blow-out portion 42 is located at the downstream end 45 of the bell mouth 40. The blow-out portion 42 is curved such that its inner diameter decreases towards the upstream end 46 of the bell mouth 40. The cylindrical portion 43 extends continuously from the upstream end of the blow-out portion 42 towards the upstream end 46 of the bell mouth 40. The inner diameter of the cylindrical portion 43 is constant from the upstream end of the blow-out portion 42 to the downstream end of the suction portion 44. The axis of the cylindrical portion 43 coincides with the axis C of the bell mouth 40.

[0068] The suction section 44 extends continuously from the upstream end of the cylindrical section 43. The suction section 44 bends in such a way that its inner diameter increases from the upstream end of the cylindrical section 43 toward the upstream end 46 of the flared mouth 40.

[0069] The thickness of the peripheral wall 41 is not particularly limited. For example, the thickness of the peripheral wall 41 is 1 mm or more. Preferably, the thickness of the peripheral wall 41 is 2 mm or more. For example, the thickness of the peripheral wall 41 is 10 mm or less. Preferably, the thickness of the peripheral wall 41 is 5 mm or less. Preferably, the thickness of the peripheral wall 41 is 2 mm or more and 5 mm or less.

[0070] There are no particular restrictions on the material of the peripheral wall 41. The peripheral wall 41 can be made of materials such as resin, ceramic, or metal. When the peripheral wall 41 is made of resin, it is preferable to maintain the strength of the flared opening 40 while achieving a lightweight design.

[0071] like Figure 2 and Figure 3 As shown, the flared opening 40 has a pressure-changing component transmission section 60. In Figure 2 and Figure 3 In the diagram, the pressure variation component permeation section 60 is indicated by a dot. Details regarding the pressure variation component permeation section 50 will be described later.

[0072] Axial flow fan

[0073] like Figure 2 and Figure 4 As shown, the axial fan 30 has a hub 31 and blades 32. The hub 31 is cylindrical. The material of the hub 31 is, for example, resin. The hub 31 has an insertion hole 31a and an outer peripheral surface 31b. The axis of the hub 31 coincides with the axis C2 of the axial fan 30. The insertion hole 31a is located at the center of the hub 31. The rotating shaft 12a of the axial fan motor 12 is inserted into the insertion hole 31a. The axial fan 30 rotates in one direction by the driving force of the axial fan motor 12. The axial fan 30 rotates in the rotation direction X by rotating the rotating shaft 12a. The rotation direction X is the rotation direction of the rotating shaft 12a.

[0074] The number of blades 32 is 5 or less. For example, there may be 3 blades. The number of blades 32 can also be 5, 4, or 2. The blades 32 are disposed on the outer peripheral surface 31b of the hub 31. The blades 32 extend radially from the outer peripheral surface 31b along the hub 31. The radial direction of the hub 31 is orthogonal to the rotation axis 12a of the axial fan motor 12. The radial direction of the axial fan 30 is consistent with the radial direction of the hub 31. The blades 32 are spaced apart from each other in the rotation direction X. The three blades 41 are of the same shape.

[0075] like Figure 5As shown, the blade 32 has a positive pressure surface 32a and a negative pressure surface 32b. The positive pressure surface 32a is the blade surface that becomes the positive pressure side due to airflow when the axial fan 30 is rotated. The negative pressure surface 32b is the blade surface that becomes the negative pressure side due to airflow when the axial fan 30 is rotated. When the blade 32 has a porous portion 61, the positive pressure surface 32a and the negative pressure surface 32b are connected through the pores of the porous portion 61. The positive pressure surface 32a is the surface on which air flows out from the porous portion 61 when the axial fan 30 is rotated. The negative pressure surface 32b is the surface on which air flows in from the porous portion 61 when the axial fan 30 is rotated.

[0076] like Figure 2 and Figure 4 As shown, the blade 32 has a body 33. The body 33 is made of, for example, resin. The hub 31 is integrally formed with the body 33. The hub 31 and the body 33 are integrally formed, for example, by injection molding. The blade 32 has a porous portion 61. The porous portion 61 is included in the pressure-varying component permeation portion 60. Figure 2 and Figures 4 to 6 In the diagram, the porous portion 61 is represented by a dot. The porous portion 61 is disposed in the turbulence interference portion 50 of the axial flow fan 30. Details regarding the turbulence interference portion 50 and the porous portion 61 will be described later.

[0077] The main body 33 has a leading edge 33a, a trailing edge 33b, an inner peripheral edge 33c, and an outer peripheral edge 33d. The leading edge 33a is the front edge located in the rotation direction X. The trailing edge 33b is the rear edge located in the rotation direction X. The leading edge 33a is curved. The leading edge 33a is curved in an arc shape towards the trailing edge 33b. The trailing edge 33b is curved. The trailing edge 33b is curved in an arc shape towards the downstream side in the rotation direction X. The inner peripheral edge 33c engages with the hub 31. The inner peripheral edge 33c extends between the leading edge 33a and the trailing edge 33b. The outer peripheral edge 33d extends between the leading edge 33a and the trailing edge 33b. In the radial direction of the axial fan 30, the dimension of the hub 31 from the rotation shaft 12a to the inner peripheral edge 33c is shorter than the dimension of the hub 31 from the rotation shaft 12a to the outer peripheral edge 33d. The outer peripheral edge 33d is curved. The outer periphery 33d is curved in an arc shape, protruding radially toward the axial fan 30.

[0078] like Figure 6As shown, the dimension from the leading edge 33a to the trailing edge 33b is defined as the first dimension L1. The first dimension L1 is the dimension of an imaginary line connecting the points of the axial fan 30 with the same radial dimension from the axis C2 of the axial fan 30 between the leading edge 33a and the trailing edge 33b. More specifically, when depicting a circle centered on the axis C2 of the axial fan 30, the first dimension L1 is the length of the arc extending between the leading edge 33a and the trailing edge 33b of the same blade 32. The dimensions of each first dimension L1 vary depending on the radial dimension of the axial fan 30 from the axis C2 of the axial fan 30.

[0079] Reference Figure 5 The leading edge portion 34 and trailing edge portion 35 of the blade 32 will be described. The first dimension L1 is divided into the leading edge portion 34 and the trailing edge portion 35 by an imaginary line connecting the center points of the first dimension L1. For example, the portion between the center position P1 of the first dimension L1 and the leading edge 33a is the leading edge portion 34, and the portion between the center position P1 of the first dimension L1 and the trailing edge 33b is the trailing edge portion 35. The leading edge portion 51 is heavier than the trailing edge portion 52. For example, by making the body 33 gradually thicken from the trailing edge 33b towards the leading edge 33a, the leading edge portion 34 is heavier than the trailing edge portion 35. Alternatively, the leading edge portion 51 can be made heavier than the trailing edge portion 52 by making a portion of the leading edge portion 51 thicker than the trailing edge portion 52.

[0080] <Turbulent Interference Section>

[0081] The axial fan 30 and the flare 40 have a turbulence interference section 50. For example, the turbulence interference section 50 includes a part of the axial fan 30 or a part of the flare 40 where turbulence is easily interfered with when pressure changes occur in the air between the flare 40 and the axial fan 30.

[0082] like Figure 2 As shown, the turbulence interference section 50 is disposed on the axial fan 30 or the bell mouth 40. The turbulence interference section 50 can be disposed on the axial fan 30 or the bell mouth 40. The turbulence interference section 50 can also be disposed on both the axial fan 30 and the bell mouth 40. The turbulence interference section 50 has an overlapping section 51 and an extension section 52.

[0083] The overlapping portion 51 is the portion where the blade 32 and the flare 40 overlap in the radial direction of the axial fan 30. For example, when an imaginary cylinder formed by the rotational trajectory of the blade 32 is projected onto the flare 40 in the radial direction of the axial fan 30, the overlapping portion 51 of the flare 40 is defined as the portion where the imaginary cylinder and the flare 40 overlap. More specifically, when an imaginary cylinder formed by the trajectory of the outer periphery 33d of the blade 32 is projected onto the flare 40 in the radial direction of the axial fan 30, the overlapping portion 51 of the flare 40 is defined as the portion where the imaginary cylinder and the flare 40 overlap. When the flare 40 is projected onto the blade 32 in the radial direction of the axial fan 30, the overlapping portion 51 of the blade 32 is defined as the portion where the flare 40 and the blade 32 overlap.

[0084] The overlapping portion 51 is disposed on the flare 40 and the axial fan 30. The overlapping portion 51 varies depending on the positional relationship between the axial fan 30 and the flare 40. For example, the portion of the flare 40 corresponding to the overlapping portion 51 is a part of the outlet portion 42, the cylindrical portion 43, and a part of the intake portion 44 of the flare 40. For example, the portion of the axial fan 30 corresponding to the overlapping portion 51 is a part of the trailing edge portion 35 of the blade 32.

[0085] The extension portion 52 is disposed on the upstream and downstream sides of the overlapping portion 51. In other words, the extension portion 52 is disposed on both sides of the overlapping portion 51 in the axial direction of the axial fan 30. Alternatively, the extension portion 52 may be disposed on only one side of the overlapping portion 51 in the axial direction of the axial fan 30.

[0086] The extension 52 varies according to the positional relationship between the axial fan 30 and the flare 40. Figure 3 In this configuration, the exhaust portion 42 and the intake portion 44 are curved in a manner that extends radially in the flare opening 40, thereby avoiding interference of turbulence at the exhaust portion 42 and the intake portion 44. Therefore, the flare opening 40 does not have a portion corresponding to the extension portion 52. The extension portion 52 of the axial fan 30 includes a portion of the trailing edge portion 35 of the blade 32. The extension portion 52 of the axial fan 30 may also include a portion of the leading edge portion 34 of the blade 32.

[0087] Reference Figure 7 The relationship between the length h of the axial extension 52 of the axial fan 30 and the radius R of the axial fan 30 will be explained. Figure 7 The diagram shows the magnitude of the low-noise effect relative to the ratio of the length h of the extension 52 to the radius R of the axial fan 30. Figure 7 The charts were observed through experiments. For example... Figure 7 As shown, by setting the length h to less than 0.1 times the radius R, the airflow noise can be appropriately reduced. Therefore, it is preferable to set the length h of the axial extension 52 of the axial fan 30 to less than 0.1 times the radius R of the axial fan 30.

[0088] like Figure 2 As shown, within the range of the turbulence interference section 50, a pressure variation component permeation section 60 is provided on the blade 32 or the flare 40. In other words, the pressure variation component permeation section 60 is provided within the range of the portion of the axial fan 30 or the flare 40 corresponding to the turbulence interference section 50. Preferably, the entire pressure variation component permeation section 60 is provided within the range of the turbulence interference section 50.

[0089] <Pressure-changing component permeable section and porous section>

[0090] Reference Figures 2 to 6 and Figure 8 The pressure fluctuation component permeation section 60 and the porous section 61 will be described below. The pressure fluctuation component permeation section 60 is configured to reduce the pressure fluctuation generated between the axial fan 30 and the flare 40. The pressure fluctuation component permeation section 60 is provided on the blade 32 of the axial fan 30 or the peripheral wall 41 of the flare 40. In this embodiment, the pressure fluctuation component permeation section 60 is provided on both the blade 32 and the peripheral wall 41.

[0091] Within the turbulence interference section 50, when a pressure variation component passage 60 is provided at the flare opening 40, the pressure variation component passage 60 is discontinuously arranged in the circumferential direction of the flare opening 40. For example, multiple pressure variation component passages 60 are arranged at intervals in the circumferential direction of the flare opening 40. For example, multiple pressure variation component passages 60 are arranged at equal intervals in the circumferential direction of the flare opening 40.

[0092] For example, the pressure variation component permeation section 60 is provided with a number of blades corresponding to the number of blades 32 at the portion of the peripheral wall 41 corresponding to the turbulence interference section 50. Figure 3 As shown, three pressure-changing component permeation sections 60 are provided circumferentially on the peripheral wall 41 of the flared mouth 40. For example, the pressure-changing component permeation sections 60 are provided across a portion of the blowing section 42, the cylindrical section 43, and a portion of the suction section 44 of the peripheral wall 41.

[0093] The surface of the pressure-changing component permeation section 60 is coplanar with the surfaces of the blowing section 42, the cylindrical section 43, and the suction section 44 of the peripheral wall 41. The thickness of the pressure-changing component permeation section 60 is substantially the same as the thickness of the peripheral wall 41 other than the pressure-changing component permeation section 60.

[0094] The pressure variation component permeation section 60 is composed of a porous body. The porous body extends through the peripheral wall 41 in the thickness direction. The porous body has pores communicating with the outside. These pores are those that connect the peripheral wall 41 in the thickness direction. The average pore diameter is not particularly limited. Preferably, the average pore diameter is 1000 μm or less, more preferably 700 μm or less. The method for measuring the average pore diameter is not particularly limited. For example, the average pore diameter can be measured by a gas adsorption method, also known as the BET method.

[0095] There are no particular limitations on the material of the pressure variation component permeation section 60. The porous material can be, for example, resin, ceramic, or metal. For example, the resin is a foaming resin. For example, ceramic or metal is a porous sintered body. Metal can also be a mesh, also known as a mesh. When the porous material is a porous sintered body, it is easier to control the average pore size, and therefore is preferred.

[0096] There are no particular limitations on the method of providing the pressure-changing component passage 60 on the peripheral wall 41 of the flared opening 40. For example, by providing an opening in the peripheral wall 41 of the flared opening 40 for fitting the pressure-changing component passage 60, and fitting the pressure-changing component passage 60, which has a predetermined shape, into the opening, the pressure-changing component passage 60 can be provided on the peripheral wall 41. The pressure-changing component passage 60 can also be mounted to the portion of the peripheral wall 41 of the flared opening 40 corresponding to the opening using a known adhesive. The pressure-changing component passage 60 can also be provided on the flared opening 40 by insert molding.

[0097] When the pressure-changing component permeation section 60 is provided on the blade 32, the pressure-changing component permeation section 60 includes a porous section 61. The porous section 61 is made of materials such as resin, ceramic, or metal. For example, the resin is a foamed resin. For example, the ceramic or metal is a porous sintered body. The metal can also be a mesh, also known as a mesh. When the porous body is made of a porous sintered body, it is easier to control the average pore size, and therefore it is preferred.

[0098] The strength of the porous portion 61 is lower than that of the main body 44. The porous portion 61 is disposed in a region surrounded by a leading edge 33a, a trailing edge 33b, an inner peripheral edge 33c, and an outer peripheral edge 33d. The porous portion 61 is generally surrounded by the main body 33, which has a higher strength than the porous portion 61. The porous portion 61 has pores communicating with the outside between the positive pressure surface 32a and the negative pressure surface 32b. The average pore diameter is preferably 1000 μm or less, more preferably 700 μm or less. The thickness of the porous portion 61 is, for example, 5 mm or less. The porous portion 61 is integrally disposed with the main body 33. The porous portion 61 is integrally disposed with the main body 33, for example, by insert molding, bonding, or embedding.

[0099] The porous portion 61 is quadrilateral in shape. For example, the four corners of the porous portion 61 are curved. Figure 6 As shown, the dimension of the imaginary line connecting the axial fan 30 between the leading edge 33a and the porous part 61, with the same radial dimension from the axis C2 of the axial fan 30, is set as the configuration distance L2. The configuration distance L2 is, for example, the length of the arc extending between the leading edge 33a of the same blade 32 and the first end 61a of the porous part 61 on the leading edge 33a side, when drawing a circle centered on the axis C2 of the axial fan 30. Equation (1) holds true at the location with the same radial dimension from the rotation axis 12a.

[0100] Equation (1): {(L2 / L1)×100}≥40

[0101] According to equation (1), it can be said that the porous portion 61 is located at a position extending rearward from the leading edge 33a to a position of more than 40% of the first dimension L1. Figure 6 The diagram shows a boundary line L11 representing a position 40% of the first dimension L1 from the leading edge 33a. A first region 36 is defined between the leading edge 33a and the boundary line L11. A second region 37 is defined between the boundary line L11 and the trailing edge 33b. The boundary line L11 is included in the second region 37. A porous portion 61 is only provided in the second region 37. The porous portion 61 is not provided in the first region 36.

[0102] In this embodiment, both the first dimension L1 and the arrangement distance L2 change with the radial position change from the rotation axis 12a. In this case, the porous part 61 of this embodiment is located within the range of the turbulent interference part 50 and at a position where equation (1) holds.

[0103] like Figure 6 As shown, the distance from the axis C2 of the axial fan 30 to the outer perimeter 33d or the extension of the outer perimeter 33d is defined as the radius R. The distance from the inner perimeter 33c to the second end 61b of the porous part 61 on the side near the outer perimeter 33d is defined as the first blade length R1. Equation (2) holds regarding the relationship between the radius R and the first blade length R1. According to Equation (2), it can be said that the porous part 61 is the portion of the blade 32 arranged radially in the axial fan 30, from the rotation axis 12a to 70% of the radius R of the axial fan 30.

[0104] Equation (2): {(R 1 / R)×100}≥70

[0105] The porous portion 61 is provided on the blade 32 to suppress noise generated accompanying the rotation of the axial fan 30. When the flare 40 has a pressure variation component permeation portion 60 and the blade 32 has the porous portion 61, the noise reduction effect based on the porous portion 61 varies depending on its placement within the turbulence interference portion 50. For example... Figure 2 As shown, the dimension from the upstream end to the downstream end of the turbulence interference section 50 is defined as the axial length H. The axial length H is the dimension obtained by adding the length of the overlapping section 51 and the length h of the extension section 52 in the axial direction. Figure 8 As shown, a low-noise effect was confirmed by providing a porous part 61 near the middle of the turbulence interference part 50 of the blade 32 in the axial length H.

[0106] like Figure 6 As shown, the line passing through the midpoint of the blade 32 among the imaginary lines of the first dimension L1 is defined as the intermediate first dimension L3. In the radial direction of the axial fan 30, the distance from the inner periphery 33c to the intermediate first dimension L3 is the second blade length R2. In the radial direction of the axial fan 30, the distance from the intermediate first dimension L3 to the outer periphery 33d is the third blade length R3. When the blade 32 is divided into an inner peripheral region 38 and an outer peripheral region 39, the portion of the second blade length R2 in the blade 32 is the inner peripheral region 38. When the blade 32 is divided into an inner peripheral region 38 and an outer peripheral region 39, the portion of the third blade length R3 in the blade 32 is the outer peripheral region 39. The inner peripheral region 38 is the region closer to the hub 31 than the outer peripheral region 39. The outer peripheral region 39 is the region closer to the outer periphery 33d than the inner peripheral region 38.

[0107] Table 1 shows the difference in low-noise effect resulting from the mounting position of the porous portion 61 in the turbulence interference portion 50 of the blade 32 when both the turbulence interference portion 50 of the horn 40 and the turbulence interference portion 50 of the blade 32 are provided with pressure variation component permeation portions 60. "Low-noise effect" in Table 1 refers to the reduced noise value. "Combined use" in Table 1 indicates the case where both the horn 40 and the blade 32 are provided with pressure variation component permeation portions 60. In Table 1, the case where the porous portion 61 is mounted in the turbulence interference portion 50 of the blade 32 at the outer peripheral region 39 of the blade 32 is considered the first embodiment. In Table 1, the case where the porous portion 61 is mounted in the turbulence interference portion 50 of the blade 32 at the trailing edge 35 of the blade 32 is considered the second embodiment.

[0108] As shown in the second row of Table 1, when the pressure variation component permeation section 60 is provided only in the turbulence interference section 50 of the horn 40, the low noise effect value is 2.0 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 and the outer peripheral region 39 of the blade 32, the low noise effect value is 2.0 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn 40 and the turbulence interference section 50 and the outer peripheral region 39 of the blade 32, the low noise effect value is 3.5 dBA. In the first embodiment, the low noise effect value when the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn 40 and the turbulence interference section 50 and the outer peripheral region 39 of the blade 32 is smaller than the value obtained by adding the low noise effect values ​​when the pressure variation component permeation section 60 is provided only in either the turbulence interference section 50 of the horn 40 or the turbulence interference section 50 and the outer peripheral region 39 of the blade 32.

[0109] As shown in the fourth row of Table 1, when the pressure variation component permeation section 60 is provided only in the turbulence interference section 50 of the horn nozzle 40, the low noise effect value is 2.0 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 and the trailing edge section 35 of the blade 32, the low noise effect value is 1.5 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn nozzle 40 and the turbulence interference section 50 and the trailing edge section 35 of the blade 32, the low noise effect value is 4.0 dBA. In the second embodiment, the low noise effect value when the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn nozzle 40 and the turbulence interference section 50 and the trailing edge section 35 of the blade 32 is higher than the value obtained by adding the low noise effect values ​​obtained when the pressure variation component permeation section 60 is provided only in either the turbulence interference section 50 of the horn nozzle 40 or the turbulence interference section 50 and the trailing edge section 35 of the blade 32.

[0110] [Table 1]

[0111]

[0112] The area of ​​the porous portion 61 is smaller than the area of ​​the blade 32. For example, the area of ​​the overall positive pressure surface 32a is larger than the area of ​​the porous portion 61. In this embodiment, the area of ​​the porous portion 61 is 30% or less of the area of ​​the blade 32. For example, the area of ​​the porous portion 61 is 30% or less relative to the overall area of ​​the positive pressure surface 32a.

[0113] <The Role of the First Implementation Method>

[0114] As shown in Table 1, when both the axial fan 30 and the flare 40 are provided with pressure variation component permeation sections 60, the low-noise effect varies depending on the arrangement of the porous portion 61 in the axial fan 30. When the pressure variation component permeation sections 60 are provided in both the turbulence interference section 50 of the flare 40 and the turbulence interference section 50 and trailing edge portion 35 of the blade 32, a higher low-noise effect can be obtained than when the low-noise effect is combined when the pressure variation component permeation sections 60 are provided in either the turbulence interference section 50 of the flare 40 or the turbulence interference section 50 and trailing edge portion 35 of the blade 32.

[0115] <Effects of the First Implementation Method>

[0116] The effects of the first embodiment will be explained.

[0117] (1-1) The fan unit 20 includes an axial fan 30 and a bell 40. The axial fan 30 has: a hub 31, on which a rotating shaft 12a is mounted; and blades 32 disposed on the hub 31. The axial fan 30 and the bell 40 have a turbulence interference portion 50. The turbulence interference portion 50 has: an overlapping portion 51, which is the portion where the blades 32 and the bell 40 overlap in the radial direction of the axial fan 30; and an extension portion 52, which is disposed on both sides of the overlapping portion 51 in the axial direction of the axial fan 30. The length h of the extension portion 52 in the axial direction is less than 0.1 times the radius R of the axial fan 30. Within the range of the turbulence interference portion 50, a pressure variation component permeation portion 60 is provided in the blades 32 or the bell 40. The pressure variation component permeation portion 60 is configured to reduce the pressure variation generated between the axial fan 30 and the bell 40.

[0118] According to this structure, by providing a pressure variation component permeation section 60 in the turbulence interference section 50 of the axial fan 30 or the flare 40, turbulence easily passes through the pressure variation component permeation section 60 when pressure variations occur in the air passing between the flare 40 and the axial fan 30. This allows for appropriate reduction of wind noise caused by surface vortices. For example, surface vortices are vortices generated on the surface of the blade 32 or the peripheral wall 41 of the flare 40.

[0119] (1-2) The blade 32 has a leading edge 33a located in the rotation direction X of the rotation axis 12a and a trailing edge 33b located in the rotation direction X of the rotation axis 12a. Within the range of the turbulence interference section 50, when the blade 32 is provided with a pressure variation component permeation section 60, the pressure variation component permeation section 60 includes a porous section 61. If the dimension from the leading edge 33a to the trailing edge 33b is set as a first dimension L1, the porous section 61 is provided at a position that is more than 40% of the first dimension L1 from the leading edge 33a to the rear.

[0120] According to this structure, by providing a porous part 61 at a position more than 40% of the first dimension L1 rearward from the leading edge 33a, the noise generated on the trailing edge 33b side of the blade 32 can be reduced.

[0121] (1-3) The fan unit 20 includes an axial fan 30 and a bell 40. The axial fan 30 has: a hub 31, on which a rotating shaft 12a is mounted; and blades 32 disposed on the hub 31. The axial fan 30 and the bell 40 have a turbulence interference portion 50. The turbulence interference portion 50 has: an overlapping portion 51, which is the portion where the blades 32 and the bell 40 overlap in the radial direction of the axial fan 30; and an extension portion 52, which is disposed on both sides of the overlapping portion 51 in the axial direction of the axial fan 30. The axial length h of the extension portion 52 is less than 0.1 times the radius R of the axial fan 30, within the range of the turbulence interference portion 50. Pressure variation component permeation section 60 is provided in blade 32 and flare 40. Pressure variation component permeation section 60 is configured to reduce the pressure variation generated between axial fan 30 and flare 40. Blade 32 has a leading edge 33a located in the rotation direction X of rotation axis 12a and a trailing edge 33b located in the rotation direction X of rotation axis 12a. Pressure variation component permeation section 60 provided in blade 32 includes a porous part 61. If the dimension from leading edge 33a to trailing edge 33b is defined as a first dimension L1, the porous part 61 is provided at a position that is more than 40% of the first dimension L1 from leading edge 33a to the rear.

[0122] According to this structure, by providing a pressure variation component permeation section 60 in the turbulence interference section 50 of the axial fan 30 and the horn 40, turbulence easily passes through the pressure variation component permeation section 60 when pressure variation occurs in the air between the horn 40 and the axial fan 30. Therefore, wind noise caused by surface eddies can be appropriately reduced.

[0123] (1-4) The porous part 61 is provided in the blade 32 in the radial direction of the axial fan 30, from the rotating shaft 12a to 70% of the radius R of the axial fan 30.

[0124] According to this structure, by arranging a porous part 61 in the blade 32 at a position that extends more than 40% of the first dimension L1 rearward from the leading edge 33a and up to 70% of the radius R of the axial fan 30 from the rotating shaft 12a, the noise generated on the trailing edge 33b side of the blade 32 can be reduced.

[0125] (1-5) The area of ​​the porous part 61 is less than 30% of the area of ​​the blade 32.

[0126] According to this structure, compared with the case where a porous portion 61 is provided over a large area of ​​the blade 32, the reduction in the strength of the blade 32 can be suppressed.

[0127] (1-6) The pressure variation component permeation section 60 has pores with an average pore diameter of 1000 μm or less that are connected in the thickness direction of the blade 32 or the bell mouth 40.

[0128] According to this structure, when a pressure change occurs, air near the peripheral wall 41 is allowed to pass through the pressure change component passage 50, while excess air is suppressed from passing through the pressure change component passage 50. As a result, air loss through the axial fan 30 can be reduced.

[0129] (1-7) Within the range of the turbulent interference section 50, when a pressure variation component passage section 60 is provided in the flared mouth 40, the pressure variation component passage section 60 is discontinuously arranged in the circumferential direction of the flared mouth 40.

[0130] According to this structure, compared with the case where the pressure variation component permeation portion 60 is continuously provided in the circumferential direction of the flared mouth 40, the reduction in the strength of the flared mouth 40 can be suppressed.

[0131] (1-8) The outdoor unit 10 is equipped with a fan unit 20.

[0132] According to this structure, when the air pressure changes between the horn 40 and the axial fan 30, the turbulence easily passes through the pressure change component permeator 60, thus appropriately reducing wind noise caused by surface eddies.

[0133] <Second Implementation>

[0134] Reference Figure 9 and Figure 10 A second embodiment of the fan unit 20 will be described. In this second embodiment, the differences from the first embodiment will be explained. Components identical to those in the first embodiment will be labeled with the same names and their descriptions will be omitted.

[0135] like Figure 9 and Figure 10 As shown, the trailing edge 71 of the axial fan 70 in the second embodiment includes an inner peripheral connecting portion 72, an outer peripheral connecting portion 73, and a notch dividing portion 74. The inner peripheral connecting portion 72 is connected to the inner peripheral edge 33c. The inner peripheral connecting portion 72 extends from the inner peripheral edge 33c toward the notch dividing portion 74. As the inner peripheral connecting portion 72 approaches the notch dividing portion 74 from the inner peripheral edge 33c, it tilts downstream in the rotation direction X of the axial fan 70.

[0136] The outer peripheral connecting portion 73 is connected to the outer peripheral edge 33d. The outer peripheral connecting portion 73 extends from the notch dividing portion 74 toward the outer peripheral edge 33d. As the outer peripheral connecting portion 73 approaches the notch dividing portion 74 from the outer peripheral edge 33d, it tilts toward the downstream side in the rotation direction X of the axial flow fan 70.

[0137] A notch dividing portion 74 is provided between the inner peripheral connecting portion 72 and the outer peripheral connecting portion 73. The notch dividing portion 74 connects the inner peripheral connecting portion 72 and the outer peripheral connecting portion 73. The notch dividing portion 74 includes a first portion 75, a second portion 76, and a third portion 77.

[0138] The first part 75 is connected to the inner peripheral connecting part 72. The first part 75 extends from the inner peripheral connecting part 72 toward the leading edge 33a. As the first part 75 approaches the outer peripheral edge 33d from the inner peripheral connecting part 72, it tilts upstream in the rotation direction X of the axial fan 70.

[0139] The second part 76 is connected to the outer peripheral connection part 73. The second part 76 extends from the outer peripheral connection part 73 toward the leading edge 33a. The second part 76 tilts upstream in the rotation direction X of the axial fan 70 as it moves away from the outer peripheral connection part 73. The distance between the first part 75 and the second part 76 decreases as they approach the leading edge 33a.

[0140] The third part 77 connects the first part 75 and the second part 76. The third part 77 is curved in a way that it is recessed towards the leading edge 33a. The area surrounded by the first part 75, the second part 76, and the third part 77 is a notch 78. The notch 78 is formed by the notch dividing part 74. The notch 78 is provided for the purpose of improving airflow and noise. The notch 78 is the space extending between the positive pressure surface 32a and the negative pressure surface 32b. The notch 78 is recessed towards the leading edge 33a.

[0141] like Figure 10 As shown, an imaginary line extending along the rotational direction X through the center position P2 of the third portion 77 is designated as the track L12. The center position P2 of the third portion 77 is the portion of the notch division 74 closest to the leading edge 33a. The portion of the blade 32 closer to the inner peripheral edge 33c than the track L12 is the inner peripheral region 79. The portion of the blade 32 closer to the outer peripheral edge 33d than the track L12 is the outer peripheral region 80. The track L12 is contained within the inner peripheral region 79.

[0142] When a notch 78 is provided at the trailing edge 33b, the porous portion 61 is provided in the blade 32 at a point in the axial fan 30 that is closer to the rotation axis 12a than the notch 78 in the radial direction. For example, the porous portion 61 is provided in the blade 32 at a point in the axial fan 30 that is closer to the inner periphery 33c than the track L12. Preferably, the porous portion 61 is provided in the blade 32 in the radial direction of the axial fan 30 between the first portion 75 and the inner periphery 33c.

[0143] Table 2 shows the difference in low-noise effect resulting from the mounting position of the porous portion 61 in the turbulence interference portion 50 of the blade 32 in the fan unit 20 having the second embodiment, when both the turbulence interference portion 50 of the horn 40 and the turbulence interference portion 50 of the blade 32 are provided with pressure variation component permeation portions 60. "Low noise effect" in Table 2 refers to the reduced noise value. "Combined" in Table 2 indicates the case where both the horn 40 and the blade 32 are provided with pressure variation component permeation portions 60. In Table 2, the case where the porous portion 61 is mounted in the turbulence interference portion 50 of the blade 32 in the outer peripheral region 80 of the blade 32 is designated as the third embodiment. In Table 2, the case where the porous portion 61 is mounted in the turbulence interference portion 50 of the blade 32 in the inner peripheral region 79 and the trailing edge 35 of the blade 32 is designated as the fourth embodiment.

[0144] As shown in the second row of Table 2, when the pressure variation component permeation section 60 is provided only in the turbulence interference section 50 of the horn nozzle 40, the low noise effect value is 1.8 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 and the outer peripheral region 80 of the blade 32, the low noise effect value is 0.5 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn nozzle 40 and the turbulence interference section 50 and the outer peripheral region 80 of the blade 32, the low noise effect value is 2.1 dBA. In the third embodiment, the low noise effect value when the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn nozzle 40 and the turbulence interference section 50 and the outer peripheral region 80 of the blade 32 is smaller than the value obtained by adding the low noise effect values ​​obtained when the pressure variation component permeation section 60 is provided only in either the turbulence interference section 50 of the horn nozzle 40 or the turbulence interference section 50 and the outer peripheral region 80 of the blade 32.

[0145] As shown in the fourth row of Table 1, when the pressure variation component permeation section 60 is provided only in the turbulence interference section 50 of the horn nozzle 40, the low noise effect value is 1.8 dBA. When the pressure variation component permeation section 60 is provided in the turbulence interference section 50, the trailing edge 35, and the inner peripheral region 79 of the blade 32, the low noise effect value is 1.0 dBA. When the pressure variation component permeation section 60 is provided in both the turbulence interference section 50 of the horn nozzle 40 and the turbulence interference section 50, the trailing edge 35, and the inner peripheral region 79 of the blade 32, the low noise effect value is 3.3 dBA. In the fourth embodiment, the low noise effect value obtained by combining the pressure variation component permeation portion 60 with the turbulence interference portion 50 of the horn mouth 40 and the turbulence interference portion 50, trailing edge portion 35, and inner peripheral region 79 of the blade 32 is greater than the value obtained by adding the low noise effect values ​​obtained by combining the pressure variation component permeation portion 60 with either the turbulence interference portion 50 of the horn mouth 40 or the turbulence interference portion 50, trailing edge portion 35, and inner peripheral region 79 of the blade 32.

[0146] [Table 2]

[0147]

[0148] <Effects of the Second Implementation>

[0149] The effects of the second embodiment will be explained. In addition to the effects of the first embodiment, the following effects can also be obtained in the second embodiment.

[0150] (2-1) When a notch 78 is provided on the trailing edge 71, the porous part 61 is provided in the blade 32, which is closer to the rotating shaft 12a in the radial direction of the axial fan 30 than the notch 78.

[0151] According to this structure, by arranging the porous part 61 in the radial direction closer to the rotation axis 12a than the notch 78, the noise generated on the trailing edge 71 side of the blade 32 can be reduced.

[0152] <Third Implementation Method>

[0153] Reference Figures 11 to 14 A third embodiment of the fan unit 20 will be described. In this third embodiment, the differences from the first and second embodiments will be explained. Components that are the same as those in the first and second embodiments will be omitted from description by using the same names.

[0154] like Figure 11 and Figure 12 As shown, the porous portion 61 is disposed on the blade 32, but not on the flared end 40. For example, the porous portion 61 is disposed on the body 33 of the blade 32. Figure 11 and Figure 12 In the diagram, the porous part 61 located on the blade 32 is represented by a dot.

[0155] The porous portion 61 is generally elliptical in shape. However, the shape of the porous portion 61 is not limited to elliptical; it can be circular or quadrilateral. When the porous portion 61 is elliptical, the ratio of the length of the major axis to the length of the minor axis is 1.3 or more and 1.8 or less.

[0156] The porous portion 61 is configured such that its center lies within a region defined by a circle of a predetermined radius centered on the centroid of the blade 32. This predetermined radius is smaller than the radius R of the axial fan 30. Preferably, the porous portion 61 is configured such that its center coincides with the centroid of the blade 32.

[0157] In this embodiment, the extension 52 disposed upstream of the overlapping portion 51 in the turbulence interference portion 50 is defined as the first extension 53. The first extension 53 extends from the upstream end 46 of the horn 40 toward the upstream side of the airflow generated by the axial fan 30. The length h1 of the first extension 53 is 0.1 times the radius R of the axial fan 30. Hereinafter, the region defined by the first extension 53 will be described as the first extension region.

[0158] The porous portion 61 is disposed on the blade 32 such that a portion of the porous portion 61 is disposed within the first extended region. The third end 61c of the porous portion 61, which is the end closest to the upstream side of the flared end 46 of the flared end 40, is disposed on the blade 32 within the first extended region. The length t from the upstream end 46 of the flared end 40 to the third end 61c is less than or equal to the length h1 of the first extended portion 53.

[0159] Reference Figure 13 The relationship between the ratio A1 of the length t from the upstream end 46 of the horn 40 to the third end 61c and the length h1 of the first extension 53 and the low-noise effect is explained. Figure 13 The diagram shows the low noise effect relative to the size of A1. Figure 13 The charts were observed through experiments. For example... Figure 13 As shown, by making the ratio A1 0.4 or higher and 0.9 or lower, the air supply noise can be reduced. In particular, by making the ratio A1 0.5 or higher and 0.7 or lower, the air supply noise can be appropriately reduced. Therefore, the ratio A1 is preferably 0.5 or higher and 0.7 or lower.

[0160] The area of ​​the porous portion 61 is smaller than the area of ​​the blade 32. The area of ​​the porous portion 61 is 30% or less of the area of ​​the blade 32. For example, the area of ​​the porous portion 61 is 30% or less of the total area of ​​the positive pressure surface 32a. In other words, the ratio A2 of the area of ​​the porous portion 61 to the area of ​​the blade 32 is 0.3 or less. For example, the ratio of the area of ​​the porous portion 61 to the total area of ​​the positive pressure surface 32a is 0.3 or less.

[0161] Preferably, the area of ​​the porous portion 61 is 25% or less of the area of ​​the blade 32. For example, the area of ​​the porous portion 61 is 25% or less of the area of ​​the overall positive pressure surface 32a. In other words, the ratio of A2 is 0.25 or less. For example, the ratio of the area of ​​the porous portion 61 to the area of ​​the overall positive pressure surface 32a is 0.25 or less.

[0162] Reference Figure 14 This illustrates the relationship between the maximum stress of blade A2 and blade 32. Figure 14 The figure shows the magnitude of the maximum stress of blade 32 relative to ratio A2. Figure 14 The charts were observed through experiments. For example... Figure 14 As shown, when the blade 32 is provided with a porous portion 61, by setting the ratio A2 to 0.3 or less, the increase in the maximum stress of the blade 32 can be suppressed. In particular, when the blade 32 is provided with a porous portion 61, by setting the ratio A2 to 0.25 or less, the increase in the maximum stress of the blade 32 can be appropriately suppressed. That is, when the blade 32 is provided with a porous portion 61, the ratio A2 is preferably 0.25 or less.

[0163] Preferably, the porous portion 61 is located at a position extending rearward from the leading edge 33a to a position at least 40% of the first dimension L1. The porous portion 61 is radially disposed in the portion of the blade 32 extending from the rotation axis 12a to 70% of the radius R of the axial fan 30.

[0164] Alternatively, a notch 78 may be provided at the trailing edge 33b of the blade 32. When the notch 78 is provided at the trailing edge 33b, the porous portion 61 is provided in the portion of the blade 32 that is closer to the rotation axis 12a in the radial direction than the notch 78.

[0165] <Example of Change>

[0166] In addition to the embodiments described above, the fan unit 20 and outdoor unit 10 disclosed herein may also be obtained by combining the following modifications and at least two non-contradictory modifications.

[0167] • The outdoor unit 10 can also be an outdoor unit of a heat pump type hot water supply device that generates hot water through a refrigeration cycle and stores the generated hot water.

[0168] The pressure variation component permeator 60 may also be provided only in the axial fan 30. The pressure variation component permeator 60 may also be provided only in the bell mouth 40.

[0169] The peripheral wall 41 of the flared mouth 40 may also be without the cylindrical portion 43. The peripheral wall 41 of the flared mouth 40 may also be configured such that the blowing portion 42 and the suction portion 44 are continuous.

[0170] The pressure-changing component permeation section 60 and the porous section 61 can also be porous materials having multiple through holes along one direction. For example, a porous material having multiple through holes along one direction can be produced by repeatedly inserting needle-shaped parts into a solid resin body from one direction.

[0171] In the third embodiment, in addition to the porous portion 61 provided on the blade 32, the porous portion 61 may also be provided on the flared end 40. In this modified example, the porous portion 61 is discontinuously arranged circumferentially within the turbulence interference portion 50 of the flared end 40.

[0172] The embodiments of the fan unit 20 and the outdoor unit 10 have been described above. However, it should be understood that various changes in manner and details can be made without departing from the spirit and scope of the fan unit 20 and the outdoor unit 10 as described in the claims.

[0173] Label Explanation

[0174] 10 Outdoor unit; 12a Rotating shaft; 20 Fan unit; 30 Axial flow fan; 31 Hub; 32 Blade; 33a Leading edge; 33b Trailing edge; 40 Trumpet mouth; 50 Turbulent interference part; 51 Overlapping part; 52 Extension part; 61 Porous part; 70 Axial flow fan; 71 Trailing edge; 78 Notch; h Length; L1 First dimension; R Radius; X Rotation direction.

Claims

1. A fan unit (20) comprising an axial fan (30) and a flare (40), wherein, The axial fan (30) has: Hub (31), rotating shaft (12a) is mounted on hub (31); and Blade (32), which is disposed on the hub (31). The axial fan (30) has a turbulence interference section (50). The turbulence interference section (50) has: The overlapping portion (51) is the portion where the blade (32) and the flare (40) overlap radially in the axial flow fan (30); as well as An extension (52) is disposed on both sides of the overlapping portion (51) in the axial direction of the axial fan (30). The length (h) of the extension (52) in the axial direction is less than 0.1 times the radius (R) of the axial fan (30). Within the range of the turbulent interference section (50), a porous section (61) is provided on the blade (32). The area of ​​the porous part (61) is less than 30% of the area of ​​the blade (32). The extension (52) includes a first extension (53), which is disposed upstream of the overlapping portion (51) in the turbulence interference portion (50). A portion of the porous portion (61) is disposed on the blade (32) in such a manner that it is located within a first extended region defined by the first extended portion (53).

2. The fan unit according to claim 1, wherein, The area of ​​the porous part (61) is less than 25% of the area of ​​the blade (32).

3. The fan unit according to claim 1, wherein, The blade (32) has: The leading edge (33a) is located in front of the rotation direction (X) of the rotation axis (12a); and The trailing edge (33b) is located behind the axis of rotation (12a) in the direction of rotation (X). If the dimension from the leading edge (33a) to the trailing edge (33b) is set as the first dimension (L1), then the porous part (61) is located at a position that extends more than 40% of the first dimension (L1) from the leading edge (33a) to the rear.

4. The fan unit according to claim 1 or 2, wherein, The porous portion (61) is the portion of the blade (32) arranged radially up to 70% of the radius (R) from the rotating shaft (12a) to the axial fan (30).

5. The fan unit according to claim 1 or 2, wherein, The blade (32) has a trailing edge (33b) located in the rotational direction (X) of the rotation axis (12a). A notch (78) is provided at the trailing edge (33b). The porous portion (61) is disposed in the portion of the blade (32) that is closer to the rotation axis (12a) in the radial direction than the notch (78).

6. The fan unit according to claim 1 or 2, wherein, The porous part (61) has pores with an average pore diameter of less than 1000 μm that are connected in the thickness direction of the blade (32).

7. The fan unit according to claim 1 or 2, wherein, The flared opening (40) has the overlapping portion (51). Within the range of the overlapping portion (51), the porous portion (61) is provided at the flared opening (40). The porous portion (61) is discontinuously arranged in the circumferential direction of the flared mouth (40).

8. An outdoor unit comprising the fan unit (20) as described in claim 1 or 2.

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