Axial fan housing and axial fan

Abstract

To provide a housing of an axial flow fan which enables improvement of cooling efficiency without increasing the size, and to provide the axial flow fan.SOLUTION: A housing of an axial flow fan, which causes air to flow in an axial direction, includes: a frame part including a wind tunnel part, in which air flows, on an inner surface; multiple stator blade parts extending from the inner surface to the radial inner side; a motor housing part supported at the radial inner side of the stator blade parts; and a motor part supported at one axial side of the motor housing part. A part of each stator blade part is provided on a surface at the other axial side of the motor housing part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a housing for an axial flow fan and an axial flow fan. [Background technology]

[0002] As electronic devices become smaller and faster, they generate more heat. Therefore, axial fans are widely used to cool these devices. However, in recent years, cooling electronic devices requires higher airflow-static pressure characteristics than ever before, and the motors that drive the fans are generating more heat.

[0003] If the temperature of the motor rises, the electronic components and bearings used in the motor will be exposed to high temperatures, which may lead to deterioration of the components and a shortened lifespan. Therefore, lowering the temperature of the motor is essential to improving quality.

[0004] Patent Document 1 discloses an axial fan in which heat dissipation fins are arranged on the surface of the motor base opposite the bearing support. In the axial fan disclosed in Patent Document 1, the heat dissipation fins efficiently dissipate heat from the circuit board, preventing it from being conducted to the spokes. Patent Document 1 also discloses that the axial fan further improves the heat dissipation effect and prevents deformation of the casing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-094228 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the axial flow fan disclosed in Patent Document 1 has the problem that the provision of heat dissipation fins increases the axial dimension and size of the fan. In addition, the heat dissipation fins are arranged locally, which makes the cooling efficiency insufficient.

[0007] The present invention has been made in consideration of the above points, and an object of the present invention is to provide an axial flow fan housing and an axial flow fan that improve cooling efficiency without increasing the size. [Means for solving the problem]

[0008] One aspect of the housing of an axial fan of the present invention is a housing for an axial fan that flows air in the axial direction, and comprises a frame portion having an air channel on its inner surface through which the air flows, a plurality of stator blade portions extending radially inward from the inner surface, a motor housing portion supported radially inside the stator blade portions, and a motor portion supported on one axial side of the motor housing portion, and a portion of the stator blade portions is provided on the surface of the motor housing portion on the other axial side.

[0009] One aspect of the axial flow fan of the present invention includes the housing of the axial flow fan described above and an impeller rotated by the motor. [Effects of the Invention]

[0010] According to one aspect of the present invention, the cooling efficiency of an axial flow fan housing and an axial flow fan can be improved without increasing the size. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a view of the axial flow fan of this embodiment as seen from above. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, showing the axial flow fan of this embodiment. [Figure 3] FIG. 3 is a bottom view of the axial flow fan of this embodiment. [Figure 4]FIG. 4 is a partial perspective view of the axial flow fan of this embodiment as viewed from below. DETAILED DESCRIPTION OF THE INVENTION

[0012] An axial flow fan according to an embodiment of the present invention will now be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments and can be modified as desired within the scope of the technical concept of the present invention. In addition, in the following drawings, the scale and number of components may differ from the actual structure in order to make each component easier to understand.

[0013] As shown in FIG. 1, an axial flow fan 10 of this embodiment is used, for example, as an electric cooling fan for cooling electronic devices.

[0014] 1 to 3, the axial flow fan 10 includes an impeller 20, a housing 70, and a circuit board 80. The impeller 20 is rotatable about a central axis J that extends in one direction.

[0015] In the XYZ coordinate system shown in each figure, the Z-axis direction is the vertical direction parallel to the direction in which the central axis J extends. The X-axis direction is the horizontal direction perpendicular to the Z-axis direction. The Y-axis direction is the horizontal direction perpendicular to both the Z-axis direction and the X-axis direction. In the following description, the Z-axis direction, i.e., the direction parallel to the central axis J, will be simply referred to as the "axial direction," the radial direction centered on the central axis J will be simply referred to as the "radial direction," and the circumferential direction centered on the central axis J will be simply referred to as the "circumferential direction." The direction parallel to the Z-axis direction will be referred to as the "upper side." The positive side of the Z-axis direction will be referred to as the "upper side," and the negative side of the Z-axis direction will be referred to as the "lower side." In this embodiment, the "upper side" corresponds to one side in the axial direction, and the "lower side" corresponds to the other side in the axial direction. Note that the vertical direction, horizontal direction, upper side, and lower side are names used merely for the purpose of explanation and do not limit the actual positional relationship or direction.

[0016] The impeller 20 has an impeller cup 21 and a plurality of blades 22. The impeller cup 21 is cylindrical and opens downward. A plurality of the blades 22 (five in FIG. 1) are arranged along the circumferential direction on the outer circumferential surface of the impeller cup 21.

[0017] The housing 70 includes a frame portion 50, a plurality of stator blade portions 60, a motor housing portion 40, a motor portion 30, and a rib portion 43. As shown in FIG. 2 , the motor portion 30 is disposed radially inside the impeller 20 and rotates the impeller 20 around the central axis J. More specifically, the motor portion 30 is disposed inside the impeller cup 21. In this embodiment, the motor portion 30 rotates the impeller 20, for example, counterclockwise when viewed from above. In the following description, the side on which the blades 22 move in the circumferential direction, i.e., the side moving counterclockwise when viewed from above, may be referred to as the “downstream side.” The side opposite the side on which the blades 22 move in the circumferential direction, i.e., the side moving clockwise when viewed from above, may be referred to as the “upstream side.” An arrow DR in each drawing indicates the direction of rotation of the impeller 20. In this embodiment, the downstream side corresponds to the other circumferential side, and the upstream side corresponds to one circumferential side.

[0018] The motor unit 30 includes a shaft 31, a stator 34, a rotor cup 32, and a rotor magnet 33. The shaft 31 extends axially around a central axis J. The shaft 31 is inserted radially inside a stator support unit 41 (described later). The shaft 31 is rotatably supported on the radially inner surface of the stator support unit 41 via a bearing. The rotor cup 32 is fixed to the upper end of the shaft 31. The stator 34 is annular and surrounds the shaft 31 circumferentially. The stator 34 is fixed to the outer peripheral surface of the stator support unit 41. The method of fixing the stator 34 is not particularly limited and may include fitting, bonding, press-fitting, etc. The stator 34 is electrically connected to a circuit board 80.

[0019] The rotor cup 32 is cylindrical and opens downward, and is disposed radially outward from the stator 34. An upper portion of the rotor cup 32 is disposed radially inward from the impeller cup 21. The rotor cup 32 is fixed to the impeller cup 21. Note that the fixing structure of the rotor cup 32, impeller cup 21, and shaft 31 is not limited to this. The rotor magnet 33 is fixed to the inner circumferential surface of the rotor cup 32. The rotor magnet 33 is, for example, cylindrical. The rotor magnet 33 faces the stator 34 radially outward from the stator 34 with a radial gap therebetween.

[0020] The motor housing portion 40 supports the motor portion 30 from above. The motor housing portion 40 supports the motor portion 30 below the impeller 20. The motor housing portion 40 has an accommodating portion 42 and a stator support portion 41. The accommodating portion 42 is cup-shaped and opens upward. The accommodating portion 42 accommodates the circuit board 80. The accommodating portion 42 is disposed below the motor portion 30.

[0021] The accommodation portion 42 has a bottom surface portion 42a and a tubular portion 42b. The bottom surface portion 42a expands in the radial direction. The tubular portion 42b is cup-shaped and extends upward from the radial outer edge of the bottom surface portion 42a. The tubular portion 42b circumferentially surrounds the radial outside of the circuit board 80. The stator support portion 41 extends upward from the bottom surface portion 42a. The stator support portion 41 is cylindrical and has a center on the central axis J.

[0022] The circuit board 80 has a plate shape that expands in the radial direction. The circuit board 80 is disposed radially inside the cylindrical portion 42b. The circuit board 80 is disposed below the motor portion 30, and at least a portion of the circuit board 80 overlaps with the motor portion 30 in the axial direction. The circuit board 80 is fixed to, for example, the motor housing portion 40. The coil of the stator 34 is connected to the circuit board 80. In this way, the circuit board 80 is electrically connected to the motor portion 30.

[0023] As shown in Figures 2 and 3, the frame 50 has a rectangular cylindrical shape extending in the axial direction. The frame 50 surrounds the impeller 20 and the motor unit 30 from the radially outer side in the circumferential direction. The frame 50 has a peripheral wall 51. The peripheral wall 51 has a cylindrical shape extending in the axial direction. The frame 50 defines an air channel 52 by an inner surface 51A of the peripheral wall 51, which is a cylindrical surface. In other words, the frame 50 has the air channel 52, through which air flows, on the inner surface 51A.

[0024] As shown in Figures 3 and 4, the multiple stator blade sections 60 each extend radially inward from the inner surface 51A of the frame section 50. The multiple stator blade sections 60 are arranged at equal intervals along the circumferential direction. In Figure 3, eleven stator blade sections 60 are provided. The stator blade sections 60 connect the inner surface 51A of the frame section 50 and the motor housing section 40. The stator blade sections 60 are arranged across the air tunnel section 52 in the radial direction. As a result, heat generated in the motor section 30 is transferred to the stator blade section 60 located radially outward of the motor housing section 40 via the stator support section 41 and the accommodating section 42 in the motor housing section 40. The heat transferred to the stator blade section 60 is efficiently dissipated by the air flowing through the air channel section 52.

[0025] When viewed in the axial direction from below, the stator blade portion 60 curves in a direction toward the upstream side, which is one circumferential side, as it moves radially outward from the side of the central axis J. When viewed in the axial direction from below, the stator blade portion 60 curves in a direction toward the counterclockwise side in the circumferential direction as it moves radially outward from the side of the central axis J. This allows the surface area of ​​the stator blade section 60 to be larger than when the stator blade section 60 extends linearly in the radial direction. As a result, the heat dissipation area in the stator blade section 60 is increased, allowing the heat generated in the motor section 30 to be dissipated more efficiently.

[0026] The stator blade portion 60 has a first portion 61 and a second portion 62. The first portion 61 is located radially inward of the outer circumferential portion 40A of the cylindrical portion 42b of the motor housing portion 40. The first portion 61 is provided on the lower surface of the motor housing portion 40. The first portion 61 protrudes downward from the bottom surface portion 42a. As a result, the heat generated in the motor section 30 is transferred to the stationary blade section 60 also below the motor housing section 40, and is dissipated more efficiently by the air flowing through the air channel section 52.

[0027] The second portion 62 is located radially outward from the outer circumferential portion 40A of the cylindrical portion 42b of the motor housing portion 40. The first portion 61, the second portion 62, and the motor housing portion 40 are integral with each other. The first portion 61, the second portion 62, and the motor housing portion 40 are an integrally molded body. The first portion 61 and the second portion 62 are continuously connected in the axial direction below the bottom surface portion 42a, and are curved in a counterclockwise circumferential direction as they move radially outward from the center axis J side. This makes it easier for the air flowing through the air tunnel section 52 and straightened by the stator blade section 60 to flow continuously and smoothly through the first section 61 and the second section 62, allowing the heat generated in the motor section 30 to be dissipated more efficiently.

[0028] Both the downstream surface and the upstream surface of the second portion 62 are inclined upward toward the upstream side. As shown in FIG. 4, the first portion 61 has a first side surface 61a and a second side surface 61b. The first side surface 61a is located on the upstream side of the first portion 61. The first side surface 61a is inclined with respect to the axial direction in a direction toward the upstream side as it moves upward from the lower tip. The second side surface 61b is located downstream of the first portion 61. The second side surface 61b is parallel to the axial direction. This allows the air flowing over the blade surface of the second portion 62 to more easily flow into the first portion 61. Therefore, the heat generated in the motor portion 30 can be more effectively dissipated below the motor housing portion 40.

[0029] The rib portions 43 protrude downward from the lower surface of the motor housing portion 40. The rib portions 43 protrude downward from the bottom surface portion 42a. The rib portions 43 are located between adjacent first portions 61 in the circumferential direction. By providing the rib portions 43 protruding downward from the lower surface of the motor housing portion 40, the heat dissipation area on the lower surface of the motor housing portion 40 is increased, and the dissipation of heat generated in the motor portion 30 can be further promoted.

[0030] The rib portion 43 has a third side surface 43a and a fourth side surface 43b. The third side surface 43a is located on the upstream side of the rib portion 43. The third side surface 43a is inclined with respect to the axial direction in a direction toward the upstream side as it moves from the lower tip to the upper side. The fourth side surface 43b is located on the downstream side of the rib portion 43. The fourth side surface 43b is parallel to the axial direction. This allows the air flowing over the blade surface of the stationary blade portion 60 to easily flow into the rib portion 43. Therefore, the heat generated in the motor portion 30 can be more effectively dissipated below the motor housing portion 40.

[0031] The rib portion 43 has the same shape as the first portion 61 when viewed from below in the axial direction. This makes it possible to more uniformly dissipate heat on the lower surface of the motor housing portion 40. It also makes it possible to improve the efficiency of designing the first portion 61, the second portion 62, and the motor housing portion 40, improve the efficiency of designing the mold used to integrally mold these portions, and reduce manufacturing costs.

[0032] According to this embodiment, a portion of the stator blade section 60 is provided on the lower surface of the motor housing section 40, which makes it possible to improve the cooling efficiency for heat generated in the motor section 30 without increasing the size of the axial fan 10.

[0033] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to these examples. The shapes and combinations of the components shown in the above examples are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0034] For example, in the above embodiment, the stationary blade portion 60, the motor housing portion 40, and the frame portion 50 are formed as an integrally molded body, but the present invention is not limited to this configuration. For example, the stationary blade portion 60 may be fabricated separately and fixed to at least one of the motor housing portion 40 and the frame portion 50.

[0035] In the above embodiment, a configuration has been described in which the rib portion 43, when viewed from below in the axial direction, has the same shape as the first portion 61, but this configuration is not limiting, and the rib portion 43 may have a different shape from the first portion 61. The rib portion 43 may be, for example, an annular rib that is centered on the central axis J and connects to multiple first portions 61. When this configuration is adopted, one or multiple rib portions may be provided. [Explanation of symbols]

[0036] 10...Axial flow fan, 20...Impeller, 30...Motor portion, 40...Motor housing portion, 40A...Outer periphery, 43...Rib portion, 43a...Third side surface, 43b...Fourth side surface, 50...Frame portion, 51A...Inner surface, 52...Wind tunnel portion, 60...Stator blade portion, 61a...First side surface, 61b...Second side surface, 70...Housing

Claims

1. A housing for an axial flow fan that flows air in an axial direction, a frame portion having an air channel portion on its inner surface through which air flows; a plurality of stator blade portions extending radially inward from the inner surface; a motor housing portion supported on the radially inner side of the stationary blade portion; a motor section supported on one axial side of the motor housing section, a cylindrical portion protruding in the other axial direction from the other axial side surface of the motor housing portion, a housing for an axial flow fan, wherein a portion of the stationary blade portion is provided on the other axial side surface of the motor housing portion and extends radially outward from the outer periphery of the cylindrical portion;

2. The stationary blade portion is a first portion located radially inward of an outer periphery of the motor housing portion; a second portion located radially outward from an outer periphery of the motor housing portion; having The housing for an axial flow fan according to claim 1 .

3. the first portion, the second portion, and the motor housing portion are integral with each other; 3. The housing for an axial flow fan according to claim 2.

4. the stationary blade portion is curved in a direction toward one circumferential side as it moves from the central axis side toward the radially outer side, The first portion and the second portion are continuously connected and curved.

4. A housing for an axial flow fan according to claim 2 or 3.

5. a first side surface on one circumferential side of the first portion is inclined with respect to the axial direction in a direction toward the one circumferential side from a tip on the other axial side toward the one axial side, a second side surface on the other circumferential side of the first portion is parallel to the axial direction; A housing for an axial flow fan according to any one of claims 2 to 4.

6. a rib portion located between the first portions adjacent to each other in the circumferential direction and protruding toward the other axial direction beyond the other axial side surface of the motor housing portion; A housing for an axial flow fan according to any one of claims 2 to 5.

7. a third side surface of the rib portion on one circumferential side is inclined with respect to the axial direction in a direction toward the one circumferential side from a tip on the other axial side toward the one axial side, a fourth side surface on the other circumferential side of the rib portion being parallel to the axial direction; 7. The housing of an axial flow fan according to claim 6.

8. When viewed in the axial direction, the rib portion has the same shape as the first portion.

7. The housing of an axial flow fan according to claim 6.

9. A housing for an axial flow fan according to any one of claims 1 to 8; an impeller rotated by the motor unit; An axial flow fan equipped with

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