Blower device

Abstract

To provide a blower capable of reducing noise generated by rotation of a rotary blade body, by reducing a flow speed fluctuation by frictional resistance of gas flowing in a ventilation passage.SOLUTION: A blower includes a rotor blade body rotatable about a central axis extending in an axial direction, a motor configured to rotate the rotor blade body, a housing having an air passage and surrounding the rotor blade body and the motor, and a noise reduction member located in the air passage. The noise reduction member is a porous member which has a plurality of air bubbles opening to the air passage on the surface side of the noise reduction member and through which a gas flow in a direction crossing the surface of the noise reduction member and the plurality of air bubbles does not pass.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a blower device. [Background technology]

[0002] There is known a blower device that blows air by rotating a rotor body using the driving force of a motor. For example, Patent Document 1 discloses a fan that blows air by rotating a rotor located within a frame. The fan described in Patent Document 1 is an axial flow fan that blows air in the axial direction of the rotor.

[0003] Furthermore, the above-mentioned blower generates noise due to wind generated by the rotation of the rotor body. Patent Document 1 discloses that such noise can be reduced by using sound-absorbing material. The fan described in Patent Document 1 has a rotor with multiple blades, a frame that houses the rotor, and a lining layer made of sound-absorbing material on the inner surface of the frame. Patent Document 1 lists felt, nonwoven fabric, etc. as the sound-absorbing material. As a result, the fan described in Patent Document 1 achieves a sound-absorbing effect. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 55-083595 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, Patent Document 1 lists felt, nonwoven fabric, etc. as the sound absorbing material. The material such as felt or nonwoven fabric has, for example, a fiber material and voids formed between the fiber material.

[0006] In response to incident sound waves, solid-borne waves propagate through the fiber material, and air-borne waves propagate through the voids. It is believed that the interaction between solid-borne waves and air-borne waves converts sound energy into heat energy within the material. It is believed that this process allows the material to achieve a sound-absorbing effect.

[0007] For this reason, in the sound-absorbing material described in Patent Document 1, gas permeates into the material, causing a loss in the flow velocity or momentum of the gas flowing on the surface of the material.

[0008] Therefore, there is a demand for a blower device that can reduce noise generated by the rotation of the rotor while preventing loss of gas flow velocity or momentum.

[0009] The object of the present invention is to provide a blower device that can reduce noise generated by the rotation of the rotor body by reducing flow velocity fluctuations due to frictional resistance of the gas flowing through the air passage while preventing loss of gas flow velocity or momentum. [Means for solving the problem]

[0010] A blower according to an exemplary embodiment of the present invention includes a rotor body rotatable about a central axis extending in an axial direction, a motor for rotating the rotor body, a housing having an air passage and enclosing the rotor body and the motor, and a noise reduction member located within the air passage. The noise reduction member is a porous member having a surface side of the noise reduction member with a plurality of air bubbles opening into the air passage. [Effects of the Invention]

[0011] According to the present invention, the noise generated by the rotation of the rotor body can be reduced by preventing loss of gas flow velocity or momentum while reducing flow velocity fluctuations caused by frictional resistance of the gas flowing through the air passage. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a front perspective view showing a schematic configuration of a blower according to an embodiment. [Figure 2] FIG. 2 is a rear perspective view showing a schematic configuration of the blower according to the first modification. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a partially enlarged cross-sectional view showing a schematic configuration of a blower according to the second modification. [Figure 5] FIG. 5 is an enlarged cross-sectional view showing a schematic configuration of a blower according to the third modification. [Figure 6] FIG. 6 is an enlarged cross-sectional view showing a schematic configuration of a blower according to the fourth modification. [Figure 7] FIG. 7 is a cross-sectional view showing a schematic configuration of a rotor blade according to an embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a schematic configuration of a rotor blade according to a comparative example that does not have a noise reduction member. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and their description will not be repeated. Furthermore, the dimensions of the components in each drawing do not faithfully represent the actual dimensions of the components and the dimensional ratios of the components.

[0014] In the following description, in the blowers 10, 11, 12, 13, 14, and 15, the direction parallel to the central axis X1 of the rotor blade 20 is referred to as the axial direction, the direction perpendicular to the central axis X1 is referred to as the radial direction, and the direction along the arc centered on the central axis X1 is referred to as the circumferential direction.

[0015] In the following description, "equivalent" does not only refer to strict equality, but also includes cases where the same can be considered to be substantially equal.

[0016] In the following description, expressions such as "fix," "connect," and "attach" include not only cases where members are directly fixed to each other, but also cases where members are fixed via other members. In other words, in the following description, expressions such as "fix" include both direct and indirect fixation of members to each other.

[0017] Fig. 1 is a front perspective view showing a schematic configuration of a blower 10 according to an embodiment. Referring to Fig. 1, blower 10 is an axial fan that draws in gas from the other side in the axial direction and sends the drawn-in gas in one side in the axial direction. Blower 10 has rotor blades 20 as a rotor body, a motor 30, a housing 40, and a noise reduction member 50.

[0018] The rotor blade 20 is a rotor body that can rotate around a central axis X1 extending in the axial direction in conjunction with the rotation of the motor 30. The rotor blade 20 has a plurality of blades that extend radially outward from the central axis X1.

[0019] The motor 30 rotates the rotor blades 20 by rotating a shaft about a central axis X1. A known motor having a rotor and a stator can be used as the motor 30.

[0020] The housing 40 has an air passage AP1 and surrounds the rotor blades 20 and the motor 30 radially outward. The housing 40 has a cylindrical portion 41 extending along the axial direction. The cylindrical portion 41 has an intake port 411 located on the other side in the axial direction and an exhaust port 412 located on one side in the axial direction. The air passage AP1 is connected to the intake port 411 and the exhaust port 412. As the rotor blades 20 rotate, gas is sucked in through the intake port 411, and the sucked gas passes through the air passage AP1 and is discharged from the exhaust port 412.

[0021] The noise reduction member 50 is a member that reduces noise generated by the rotation of the rotor blade 20. The noise reduction member 50 is located within the air passage AP1. Specifically, the noise reduction member 50 is located on at least a portion of the inner surface of the tubular portion 41, and is located opposite at least a portion of the rotor blade 20 in the radial direction of the central axis X1.

[0022] The noise reduction member 50 is a synthetic resin member having a plurality of air bubbles 51 that open to the air passage AP1 on the surface 501 side of the noise reduction member 50. The noise reduction member 50 also has a plurality of air bubbles 52 inside the noise reduction member 50. In other words, the noise reduction member 50 is a porous member having a plurality of air bubbles 51, 52. Examples of the synthetic resin member include foamed resin members such as polystyrene, polyolefin, polyester, polyurethane, ethylene-vinyl acetate copolymer resin (EVA), and polyvinyl alcohol (PVA).

[0023] The multiple cells 51, 52 are closed cells positioned at intervals from one another. The noise reduction member 50 having such multiple cells 51, 52 can be easily formed, for example, by adding a foaming agent to a synthetic resin material and foaming the foaming agent in the synthetic resin material by heating or the like.

[0024] As described above, the blower 10 includes the rotor blades 20 as rotor bodies rotatable about the central axis X1 extending in the axial direction, the motor 30 that rotates the rotor blades 20, the housing 40 that has the air passage AP1 and surrounds the rotor blades 20 and the motor 30, and the noise reduction member 50 located within the air passage AP1. The noise reduction member 50 is a porous member that has, on the surface 501 side of the noise reduction member 50, a plurality of air bubbles 51 that open to the air passage AP1.

[0025] With the above-described configuration, when gas passes through the air passage AP1 due to the rotation of the rotor blade 20 as a rotor body, it is possible to reduce the flow velocity fluctuations of a portion AF1 of the gas passing over the surface 501 of the noise reduction member 50 having the bubbles 51. The portion AF1 of the gas is, for example, gas that flows in a boundary layer that is affected by frictional resistance with respect to the surface 501 of the noise reduction member 50 due to the viscosity of the gas. This makes it possible to reduce the flow velocity fluctuations of the gas passing over the surface 501 of the noise reduction member 50. Therefore, it is possible to reduce the noise generated by these flow velocity fluctuations.

[0026] Furthermore, noise reduction member 50, which is a porous member having a plurality of bubbles 51, can prevent loss of gas flow velocity or momentum compared to materials such as nonwoven fabric. This prevents loss of gas flow velocity or momentum while reducing flow velocity fluctuations due to frictional resistance of the gas flowing through air passage AP1, thereby reducing noise generated by the rotation of rotor blade 20.

[0027] Furthermore, the noise reduction member 50 is a porous member that is impermeable to gas flow in the thickness direction of the noise reduction member 50. That is, the noise reduction member 50 is a porous member that is impermeable to gas flow in the intersecting direction of the surface 501 of the noise reduction member 50 and the plurality of cells 51. That is, gas moves within the cells 51 in the porous member, but does not substantially pass through the resin portion. Because the noise reduction member 50 is an air-tight porous member that is impermeable to gas flow, the gas flowing in the intersecting direction relative to the surface of the porous member does not enter the noise reduction member 50, which is a porous member.

[0028] More specifically, as shown in the partially enlarged cross-sectional view XS1 of the blower device 10 in FIG. 1 , the gas flow AF11 moving in a direction intersecting the surface 501 of the noise reduction member 50 changes direction at the surface 501 of the noise reduction member 50. There are several possible patterns of movement of the gas flow AF11. For example, the gas flow AF11 may bounce off the surface 501 of the noise reduction member 50 in a direction away from the surface 501 of the noise reduction member 50. Alternatively, the gas flow AF11 may change direction at the surface 501 of the noise reduction member 501 in a direction along the surface 501 of the noise reduction member 50.

[0029] Furthermore, the gas flow AF12 flowing into the plurality of bubbles 51 changes direction at the surfaces of the plurality of bubbles 51. There are several possible patterns for the movement of the gas flow AF12 flowing into the bubble 51. For example, the gas flow AF12 is considered to enter the bubble 51 in the thickness direction, then proceed along the surface of the bubble 51 and flow out. For example, the gas flow AF12 is considered to enter the bubble 51 in an oblique direction intersecting the thickness direction, then proceed along the surface of the bubble 51 and flow out. For example, the gas flow AF12 is considered to enter the bubble 51 in an oblique direction intersecting the thickness direction, then proceed along the surface of the bubble 51 and flow out. For example, the gas flow AF12 is considered to enter the bubble 51 in an oblique direction intersecting the thickness direction, then bounce off the surface of the bubble 51 in a direction away from the surface of the bubble 51.

[0030] Therefore, the gas flow AF11 moving in a direction intersecting the surface 501 of the noise reduction member 50 or the gas flow AF12 flowing into the plurality of bubbles 51 does not enter the plurality of bubbles 52 located within the noise reduction member 50.

[0031] This prevents the flow rate of the gas passing over the surface 501 of the noise reduction member 50 from decreasing due to penetration into the noise reduction member 50, thereby preventing a decrease in the flow velocity or momentum of the gas.

[0032] Furthermore, the multiple bubbles 51, 52 are closed bubbles that are spaced apart from one another. Therefore, there are walls between the bubbles that block the movement of gas. In other words, the bubbles are not connected to one another. Therefore, in the noise reduction member 50, gas does not pass from one bubble to another, and therefore a decrease in the flow rate of gas passing through the air passage AP1 can be further suppressed.

[0033] Furthermore, in the above-described configuration, the noise reduction member 50 is positioned radially opposite at least a portion of the rotor blade 20. In this manner, with a configuration in which the noise reduction member 50 is positioned radially outward of the rotor blade 20, noise generated by gas passing through the air passage AP1 located between the rotor blade 20 and the noise reduction member 50 can be further reduced.

[0034] (Variation 1) Fig. 2 is a rear perspective view showing a schematic configuration of blower 11 according to Modification 1. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. Blower 11 according to Modification 1 of the embodiment differs from blower 10 according to the embodiment in that it further includes stator vanes 422. In the following, a description of the same configuration as in the embodiment will be omitted, and only the configuration different from the embodiment will be described.

[0035] 2 and 3, the blower 11 includes a rotor blade 20, a motor 30, a housing 40, and noise reduction members 50 and 60. As shown in FIG.

[0036] The housing 40 has a cylindrical portion 41 and a support portion 42. The support portion 42 is located on one axial side of the rotor blade 20. The support portion 42 supports the rotor blade 20 and the motor 30 relative to the cylindrical portion 41. The support portion 42 has a holder 421 and a plurality of stator blades 422.

[0037] The holding portion 421 is located on one side in the axial direction from the rotor blade 20. The holding portion 421 is located in the center in the radial direction and holds the motor 30.

[0038] The plurality of stator vanes 422 extend radially outward from the radially outer end of the holder 421 and are connected to the inner surface of the cylindrical portion 41. The plurality of stator vanes 422 have the function of regulating the airflow that flows through the air passage AP1 when the rotor blades 20 rotate. The plurality of stator vanes 422 also function as ribs that connect the cylindrical portion 41 and the holder 421. Note that a lead wire for supplying power to the motor 30 may be wired to at least one of the plurality of stator vanes 422.

[0039] The noise reduction member 50 is located at a position radially facing at least a portion of the rotor blade 20 and on the other side of the support portion 42 in the axial direction.

[0040] Like the noise reduction member 50, the noise reduction member 60 is a porous synthetic resin member having a plurality of air bubbles 51, 52. A portion of the noise reduction member 60 is located on the inner surface of the tubular portion 41, which is located to the one side of the rotor blade 20 in the axial direction. Another portion of the noise reduction member 60 is located at a position radially opposite at least a portion of the rotor blade 20.

[0041] According to the above-described configuration, the plurality of stator vanes 422 can regulate the airflow, while the noise reduction member 60 can reduce noise that occurs when gas passes through the support portions 42 .

[0042] (Variation 2) 4 is a partially enlarged cross-sectional view showing the schematic configuration of blower 12 according to Modification 2. Blower 12 according to Modification 2 differs from blower 10 according to the above embodiment in that blower 12 according to Modification 2 has a noise reducing member 70 with an open-cell structure, whereas blower 10 according to the above embodiment has a noise reducing member 50 with a closed-cell structure. Below, a description of the same configuration as in the above embodiment will be omitted, and only the configuration that differs from the above embodiment will be described.

[0043] 4, blower 12 has a noise reduction member 70 with an open-cell structure. Noise reduction member 70 has a plurality of open-cell cells 71, 72, and 73. Noise reduction member 70 may also have a plurality of closed-cell cells 51 and 52. The plurality of cells may also be in contact with each other.

[0044] For example, a portion of air bubble 71 is connected to air bubble 72. A portion of air bubble 72 is connected to air bubble 73. Air bubble 71 is open to air passage AP1. Air bubble 72 is located radially outward from air bubble 71. Air bubble 73 is located further radially outward from air bubble 72. For example, gas moves through air bubbles 71, 72, and 73 in the porous member, while substantially no gas passes through the resin portion.

[0045] The continuous cells 701, which are made up of a plurality of cells connected together, may penetrate from the front surface 501 located on one surface in the thickness direction of the noise reduction member 70 to the back surface 502 located on the other surface in the thickness direction of the noise reduction member 70. Furthermore, the radial dimension of the continuous cells 702, which are made up of a plurality of cells connected together, may be smaller than the thickness TK1 of the noise reduction member 70. Therefore, even if an airflow enters the continuous cells 702, it will not reach the back surface 502 of the noise reduction member 70.

[0046] A portion of the gas passing over the surface 501 of the noise reduction member 70 when air is blown enters the open cells 701 and 702 .

[0047] The back surface 502 of the noise reduction member 70 is in contact with the inner surface of the tubular portion 41 of the housing 40. Therefore, the gas flow AF13 that has entered the open cells 701 that penetrate the noise reduction member 70 in the thickness direction changes direction on the inner surface of the tubular portion 41. The thickness TK1 of the noise reduction member 70 is a dimension that prevents substantial loss of momentum due to gas entering the open cells 701, 702.

[0048] In the above-described configuration, the multiple cells 71, 72, 73 are composed of open cells 701 in which cells are at least partially connected to other cells. If the back surface 502 or the side surfaces other than the front surface 501 of the porous noise reduction member 70 are covered with a non-breathable material that does not allow the gas to pass through, the gas can be prevented from passing through the noise reduction member 70, just like the above-described closed cells.

[0049] In the above-described configuration, the back surface 502 of the noise reduction member 70 is covered by the tubular portion 41, which is an air-impermeable member. This prevents the gas from passing through the noise reduction member 70. As a result, the gas does not pass through the noise reduction member 70, and a decrease in the flow rate can be suppressed.

[0050] (Variation 3) 5 is an enlarged cross-sectional view showing a schematic configuration of blower device 13 according to Modification 3. Blower device 13 according to Modification 3 differs from blower device 11 according to Modification 1 in that housing 40 further has inclined portion 45. Below, a description of the same configuration as in Modification 1 will be omitted, and only the configuration different from Modification 1 will be described.

[0051] 5, blower 13 has rotor blade 20, motor 30, housing 40, and noise reduction members 50 and 60. Housing 40 has a cylindrical portion 41, a support portion 42, and an inclined portion 45.

[0052] The inclined portion 45 is connected to the other axial end of the cylindrical portion 41. The inclined portion 45 is inclined radially outward from one end in the axial direction to the other. The inclination of the inclined portion 45 may be linear or curved when viewed in a cross section perpendicular to the radial direction. An intake port 451 is located at the other axial end of the inclined portion 45. From another perspective, the opening dimension of the intake port 451 is larger than the inner diameter dimension of the cylindrical portion 41. In other words, the inner diameter of the inclined portion 45 is larger than the inner diameter of the cylindrical portion 41.

[0053] The noise reduction members 50, 60 are located on at least a portion of the inner surface of the cylindrical portion 41. That is, the noise reduction members 50, 60 are not disposed on the inclined portion 45.

[0054] In the above-described configuration, the noise reduction members 50, 60 are located on the inner surface of the tubular portion 41, which is narrower than the intake port 451 located at the other axial end of the inclined portion 45, in the air passage AP1. Because the noise reduction members 50, 60 are narrow, they are located in a position where the flow of gas is easily obstructed and noise is likely to be generated. By locating the noise reduction members 50, 60 in such a position where noise is likely to be generated, it is possible to further suppress a decrease in the gas flow velocity and to further enhance the effects of noise reduction.

[0055] (Variation 4) 6 is an enlarged cross-sectional view showing a schematic configuration of a blower 14 according to Modification 4. In blower 14 according to Modification 4, noise reduction member 50 is located on the other axial side of rotor blade 20, whereas in blower 11 according to Modification 1, noise reduction member 50 is located radially opposite at least a portion of rotor blade 20. In the following, description of the same configuration as in Modification 1 will be omitted, and only the configuration that differs from Modification 1 will be described.

[0056] 6, blower 14 has rotor blades 20, motor 30, housing 40, and noise reduction members 50 and 60. Housing 40 has a cylindrical portion 410 and a support portion 42.

[0057] The axial length D410 of the cylindrical portion 410 is longer than the axial length D41 of the cylindrical portion 41 of the blower device 11 according to the first modification shown in FIG.

[0058] The noise reduction member 50 is disposed on a portion of the inner surface of the housing 40, and is located on the other side in the axial direction from the rotor blade 20. Specifically, the noise reduction member 50 is located on a portion of the inner surface of the tubular portion 410 of the housing 40, which is located on the other side in the axial direction from the rotor blade 20. Therefore, the noise reduction member 50 is located on the other side in the axial direction from the other end 21 of the rotor blade 20.

[0059] According to the above-described configuration, it is possible to reduce noise generated by gas flowing at a position in the axial direction other than the other axial end 21 of the rotor blade 20, and to suppress a decrease in the flow velocity of the gas.

[0060] (Example) Fig. 7 is a cross-sectional view showing a schematic configuration of a rotor blade 210 according to an embodiment. Fig. 8 is a cross-sectional view showing a schematic configuration of a rotor blade 200 according to a comparative example that does not have a noise reduction member. The rotor blade 210 according to the embodiment and the rotor blade 200 according to the comparative example are computer simulation models. Noise reduction members 710, 720 with an open-cell structure similar to the noise reduction member 70 in the blower 12 according to Modification 2 are arranged on the rotor blade 210. Below, a description of the same configuration as in Modification 2 will be omitted, and only the configuration that differs from Modification 2 will be described.

[0061] 7, in the rotor blade 210 according to the embodiment, noise reduction members 710, 720 with an open-cell structure are located on the surface of the rotor blade 210. The surfaces of the noise reduction members 710, 720 are located flat with no steps relative to the surface of the rotor blade 210. The noise reduction member 710 is located on one side of the rotor blade 210 in the blade thickness direction. The noise reduction member 720 is located on the other side of the rotor blade 210 in the blade thickness direction.

[0062] The cross section of the airfoil of the rotor blade 210 described below is a cross section in the direction of gas flow. Hereinafter, the direction in which a chord CH1 connecting the leading edge 211 and trailing edge 212 of the airfoil of the rotor blade 210 extends will be referred to as the chord length direction CL1. The upstream side in the gas flow will be referred to as the front side of the chord length direction CL1, and the downstream side in the gas flow will be referred to as the rear side of the chord length direction CL1. The direction perpendicular to the chord length direction CL1 will be referred to as the blade thickness direction TK1. The leading edge 211 is located at the front end of the airfoil of the rotor blade 210 in the chord length direction CL1. The trailing edge 212 is located at the rear end of the airfoil of the rotor blade 210 in the chord length direction CL1.

[0063] The rotor blade 210 has a curved surface 213 that is convex in one direction in the blade thickness direction with respect to the blade chord CH1. The noise reduction member 710 is located on at least a part of the curved surface 213. The curved surface 213 has a maximum blade thickness portion 2131 that is located at a position where the blade thickness in the blade thickness direction TK1 of the airfoil is maximum.

[0064] The noise reduction member 710 has an inlet portion 711 , an outlet portion 712 , a rear inlet portion 713 , and a rear outlet portion 714 .

[0065] The inlet section 711 is located upstream of the maximum blade thickness part 2131 in the blade chord length direction CL1. The inlet section 711 is a portion into which gas flows when the gas flows from the front to the rear of the rotor blade 210 in the blade chord length direction CL1.

[0066] The outlet portion 712 is located downstream of the inlet portion 711 in the chord length direction CL1. The outlet portion 712 is a portion from which the gas that has flowed into the inlet portion 711 flows out.

[0067] The rear inlet portion 713 is located rearward of the outlet portion 712 and a rear outlet portion 714 (described later) in the blade chord length direction CL1. The rear inlet portion 713 is a portion into which gas that has flowed rearward beyond the maximum blade thickness portion 2131 flows.

[0068] The rear outlet portion 714 is located in the chord length direction CL1 between the outlet portion 712 and the rear inlet portion 713. The rear outlet portion 714 is a portion from which the gas that has flowed into the rear inlet portion 713 flows out.

[0069] 8 for comparison, the simulation results when airflow is generated will be described below. When airflow is generated, in the rotor blade 200 according to the comparative example that does not have a noise reduction member, the main MAF 1 flows from the front to the rear of the rotor blade 200. In the rotor blade 200, a swirling MAF 11 of the main MAF 1 is generated at the rear of the rotor blade 200. As a result, a vortex is generated by the swirling MAF 11. Therefore, noise is generated due to the generation of the vortex.

[0070] On the other hand, in the rotor blade 210 according to the embodiment, the gas flow is as follows: When the airflow collides with the leading edge 211 of the rotor blade 210, the pressure on the blade surface around the leading edge 211 and the inlet portion 711 increases. As a result, part of the airflow moves near the surface of the rotor blade 210 as the main MAF1, while the rest of the airflow flows into the noise reduction member 710 from the inlet portion 711.

[0071] The outlet section 712 is located, for example, rearward of the maximum blade thickness portion 2131. The gas flow velocity is higher and the pressure is lower on the surface of the outlet section 712 than at other positions. The pressure on the surface of the outlet section 712 is, for example, negative pressure.

[0072] Furthermore, the flow velocity of the gas slows down while the pressure on the blade surface increases at the rear inlet portion 713 located rearward of the outlet portion 712. Therefore, the gas flows into the noise reduction member 710 from the rear inlet portion 713.

[0073] As described above, the pressure on the surface of the outlet portion 712 is, for example, negative pressure, so that gas that flows in from the inlet portion 711 of the noise reduction member 710 passes rearward through the noise reduction member 710 and flows out from the outlet portion 712. Gas that flows in from the rear inlet portion 713 passes forward through the noise reduction member 710 and flows out from the rear outlet portion 714.

[0074] The configuration of the rotor blade 210 can suppress the occurrence of entrainment of the mainstream MAF 1 by regulating the flow of the mainstream MAF 1 by the gas flowing out from the outlet section 712 and the rear outlet section 714. Therefore, it is possible to suppress the occurrence of vortices due to entrainment, and therefore the generation of noise.

[0075] As described above, the above-mentioned effects can also be expected in blower 15 having rotor blade 210. That is, blower 15 has rotor blade 210 as a rotor body, motor 30, housing 40, and noise reduction member 710. Rotor blade 210 has curved surface 213 that is convex in one direction in the blade thickness direction with respect to chord CH1 connecting leading edge 211 and trailing edge 212 of the airfoil of rotor blade 210. Noise reduction member 710 is located on at least a part of curved surface 213.

[0076] According to the above-described configuration, it is possible to suppress the generation of vortices due to the entrainment of the main MAF 1, and therefore it is possible to suppress the generation of noise.

[0077] Furthermore, the curved surface 213 has a maximum blade thickness portion 2131 located at the position where the blade thickness of the airfoil is maximum. The noise reduction member 710 has an inlet portion 711 and an outlet portion 712.

[0078] According to the above-described configuration, the flow of the mainstream MAF 1 can be adjusted by the gas that flows in through the inlet 711 and then flows out through the outlet 712.

[0079] (Other embodiments) Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiments, and it is possible to appropriately modify the above-described embodiments within the scope of the spirit of the present invention.

[0080] In the above-described embodiment and modifications 1-4 (hereinafter referred to as "embodiments, etc."), the noise reduction members 50, 60, 70 are foamed resin members. However, the noise reduction members may be members other than resin. For example, the noise reduction members may be metal members.

[0081] In the above-described embodiments, the noise reduction members 50, 60, and 70 are located on a portion of the inner surface of the housing 40 in the axial direction. However, the noise reduction members may be located on a portion of the inner surface of the housing in the circumferential direction, or may be located on the entire circumferential direction. Furthermore, the noise reduction members may be located on at least a portion of the surface of the rotor blades, which are rotor bodies. The noise reduction members can be located at any position within the air passage.

[0082] In the first, third, and fourth modifications, the blowers 11, 13, and 14 have noise reduction members 50 and 60. However, the noise reduction members do not necessarily have to be located on a part of the inner surface of the cylindrical portion located on one side of the rotor blade in the axial direction, and the noise reduction members do not necessarily have to be located radially outward of the rotor blade or on the other side of the rotor blade in the axial direction.

[0083] Although not specifically described in the first, third, and fourth modifications, the noise reduction member may be located on at least a portion of the surface of the stator blade.

[0084] In the above-described embodiments, the blowers 10, 11, 12, 13, and 14 are axial fans having rotor blades 20 as rotor bodies. However, the blowers may be blowers other than axial fans. The blowers may be, for example, centrifugal fans that take in air in the axial direction and exhaust air in a centrifugal direction perpendicular to the axial direction. The blowers may also be mixed-flow fans that take in air in the axial direction and exhaust air obliquely. The blowers may also have multiple rotor blades. In the blowers, the multiple rotor blades may be positioned side by side in the axial direction.

[0085] In the above-described embodiment and the like, the rotor blade 20 is located inside the housing 40. However, at least a portion of the rotor blade may protrude outward from the other axial end of the housing.

[0086] In the first, third, and fourth modifications, the blowers 11, 13, and 14 have the stator blades 422. However, the blowers do not have to have the stator blades. For example, in the blowers, ribs may support the holding portion relative to the cylindrical portion instead of the stator blades.

[0087] In the first, third, and fourth modifications, the support portion 42 is located inside the cylindrical portion 41. However, at least a portion of the support portion may protrude outward from one axial end of the cylindrical portion. For example, the stator blade may support the retainer at a position protruding outward from one axial end of the cylindrical portion.

[0088] In the third modification, the noise reducing members 50, 60 are located on at least a portion of the inner surface of the cylindrical portion 41, and are not located on the inclined portion 45. However, the noise reducing members may also be located on the inclined portion.

[0089] In the fourth modification, the noise reduction member 50 is located on the other side in the axial direction than the rotor blade 20. However, the noise reduction member may be located at a position radially opposite at least a part of the rotor blade.

[0090] In the above embodiment, the noise reduction member 720 is located on the other surface in the blade thickness direction of the rotor blade 210. However, the noise reduction member does not have to be located on the other surface in the blade thickness direction of the rotor blade.

[0091] Although not specifically described in the above embodiment, the airfoil of the rotor blade may be a symmetrical airfoil or an airfoil other than a symmetrical airfoil. The airfoil of the rotor blade may have a camber, which is the difference between the chord and the center line of the airfoil.

[0092] In the above embodiment, the noise reduction members 710, 720 have an open-cell structure. However, the noise reduction members may also have a closed-cell structure.

[0093] (Configuration example) The present technology can also be configured as follows.

[0094] (1) A blower device includes a rotor body rotatable about a central axis extending in the axial direction, a motor for rotating the rotor body, a housing having an air passage and enclosing the rotor body and the motor, and a noise reduction member located in the air passage. The noise reduction member has a plurality of bubbles on its surface side that open to the air passage, and is a porous member that is impermeable to gas flow in the direction intersecting the surface of the noise reduction member and the plurality of bubbles.

[0095] (2) In the blower device described in (1), the plurality of bubbles are positioned at intervals from one another.

[0096] (3) In the blower device described in (1), among the plurality of bubbles, the bubble is at least partially connected to another bubble.

[0097] (4) In the blower device described in any one of (1) to (3), the noise reduction member is located on the inner surface of the housing and is positioned radially opposite at least a portion of the rotor body relative to the central axis.

[0098] (5) In the blower device described in any one of (1) to (4), the housing further has a cylindrical portion extending along the axial direction and an inclined portion inclined radially outward from one end of the cylindrical portion in the axial direction toward the other end of the axial direction, and the noise reduction member is located on the inner surface of the cylindrical portion.

[0099] (6) In the blower device described in any one of (1) to (4), the housing further has a cylindrical portion extending along the axial direction and a support portion located on one side of the axial direction of the rotor body and supporting the rotor body and the motor relative to the cylindrical portion, and the noise reduction member is located on at least one of a part of the inner surface of the cylindrical portion located on one side of the axial direction than the rotor body or the surface of the support portion.

[0100] (7) In the blower device described in (6), the support portion has a stator blade.

[0101] (8) In the blower device described in any one of (1) to (7), the noise reduction member is disposed on the inner surface of the housing and is located on the other side of the rotor body in the axial direction.

[0102] (9) In the blower device described in any one of (1) to (8), the noise reduction member is a porous member that is impermeable to gas flow in the thickness direction.

[0103] (10) In the blower device described in (2) or (3), the noise reduction member is a synthetic resin member.

[0104] (11) In a blower device described in any one of (1) to (10), the airfoil of the rotor body has a curved surface that is convex in one direction in the blade thickness direction with respect to a chord connecting the leading edge and the trailing edge of the airfoil, and the noise reduction member is located on at least a part of the curved surface.

[0105] (12) In the blower device described in (11), the curved surface has a maximum blade thickness portion located at a position where the blade thickness of the airfoil is maximum, and the noise reduction member has an inlet portion located upstream of the maximum blade thickness portion in the chord length direction in which the chord extends, through which gas flows in, and an outlet portion located downstream of the inlet portion, through which the gas that has flowed into the inlet portion flows out. [Industrial Applicability]

[0106] The present invention is applicable to, for example, a blower in which rotor blades are rotated by the driving force of a motor. [Explanation of symbols]

[0107] 10, 11, 12, 13, 14, 15 Blower 20, 210 moving blade 213 Curved surface 2131 Maximum blade thickness 30 motor 40 cabinets 41, 410 Cylindrical part 411, 451 intake 412 Exhaust port 42 Support part 421 Holding part 422 Stator blade 45 Slope 50, 60, 70, 710, 720 Noise reduction materials 711 Entrance 712 Exit section 713 Rear entrance section 714 Rear exit section 501 Surface 502 Back side 51, 52, 71, 72, 73 Bubbles 701, 702 Open cell AP1 airway CH1 Wing X1 Central Axis

Claims

1. a rotor body rotatable around a central axis extending in the axial direction; a motor that rotates the rotor; a housing having an air passage and enclosing the rotor body and the motor; a noise reduction member located within the air passage; and the noise reduction member is a porous member having a plurality of cells on a surface side of the noise reduction member that open to the air passage; Blower.

2. The blower device according to claim 1, The plurality of bubbles are spaced apart from one another. Blower.

3. The blower device according to claim 1, In the plurality of bubbles, each bubble is at least partially connected to another bubble. Blower.

4. The blower device according to any one of claims 1 to 3, the noise reduction member is located on at least a portion of the inner surface of the housing and is located opposite at least a portion of the rotor body in the radial direction of the central axis. Blower.

5. The blower device according to claim 1, The housing includes: a cylindrical portion extending along the axial direction; an inclined portion connected to the other end of the cylindrical portion in the axial direction and inclined radially outward from one end to the other end in the axial direction; and The noise reduction member is located on at least a portion of the inner surface of the cylindrical portion. Blower.

6. The blower device according to any one of claims 1 to 3, The housing includes: a cylindrical portion extending along the axial direction; a support portion located on one side of the rotor body in the axial direction and configured to support the rotor body and the motor relative to the cylindrical portion; and the noise reduction member is located on at least one of a part of the inner surface of the cylindrical portion located on one side of the rotor body in the axial direction or a surface of the support portion, Blower.

7. The blower device according to claim 6, The support portion has a stator blade. Blower.

8. The blower device according to any one of claims 1 to 3, the noise reduction member is located on a part of the inner surface of the housing located on the other side of the rotor body in the axial direction, Blower.

9. The blower device according to any one of claims 1 to 3, The noise reduction member is a porous member that is impermeable to gas flow in the thickness direction. Blower.

10. The blower device according to claim 2 or 3, The noise reduction member is a synthetic resin member. Blower.

11. The blower device according to claim 1, The rotor body has a curved surface that is convex in one direction in the blade thickness direction with respect to a chord connecting a leading edge and a trailing edge in an airfoil of the rotor body, The noise reduction member is located on at least a portion of the curved surface. Blower.

12. The blower device according to claim 11, The curved surface has a maximum blade thickness portion located at a position where the blade thickness of the airfoil is maximum, The noise reduction member has a configuration in which, in a chord length direction in which the chord extends, an inlet portion located upstream of the maximum blade thickness portion and into which gas flows; an outlet portion located downstream of the inlet portion and through which the gas that has flowed into the inlet portion flows out; having Blower.

Images