Motor and air blower

Abstract

To downsize a gap between facing surfaces in a labyrinth part of a motor while ensuring the gap.SOLUTION: A motor 101 includes a rotor 1, a stator 2, and a labyrinth part 5. The rotor is rotatable about a center axis CA extending in an axis direction. The stator has a stator core 21. A plurality of coil parts 23 arranged in a circumferential direction are disposed on the stator core. The labyrinth part has a pair of metal tubular members surrounding the center axis. The pair of metal tubular members have a pair of facing surfaces facing each other in a radial direction with a gap disposed therebetween. One of the facing surfaces surrounds the other.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Conventionally, motors having a labyrinth structure consisting of a pair of diametrically opposed protrusions are known. For example, in a motor, a diametrically opposed protrusion provided on the winding side from the boss of an impeller faces a diametrically opposed protrusion formed on a standing portion of a bearing housing to form a labyrinth structure (Japanese Utility Model Application Publication No. 07-039263). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 07-039263 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in order to reduce weight and costs, the cup portions of the impeller and rotor are formed using a resin material. Therefore, usually, at least the above-mentioned ridges on the impeller side are also made of resin. For example, compared to metal parts, resin parts tend to have larger dimensional tolerances, making it difficult to reduce the gap between the opposing surfaces of the ridges that face each other in the radial direction of the labyrinth structure. In addition, if the dimensional tolerance is underestimated, there is a risk that the gap will be eliminated at least locally between the opposing surfaces of the ridges. In other words, there is a risk that the ridges on the impeller side or rotor side will come into contact with the ridges on the bearing housing side at least locally, and the sliding between the two may adversely affect the rotation of the motor.

[0005] An object of the present invention is to ensure a gap between opposing surfaces in a labyrinth portion of a motor while reducing the gap. [Means for solving the problem]

[0006] An exemplary motor of the present invention includes a rotor, a stator, and a labyrinth portion. The rotor is rotatable about a central axis extending in the axial direction. The stator has a stator core. The labyrinth portion, in which a plurality of coil portions arranged in the circumferential direction are disposed, includes a pair of metallic tubular members surrounding the central axis. The pair of metallic tubular members has a pair of opposing surfaces that are radially opposed with a gap therebetween, one surrounding the other.

[0007] An exemplary blower device of the present invention includes the above-mentioned motor and a rotor blade, the rotor blade being rotatable about the central axis together with the rotor of the motor. Effect of the Invention

[0008] According to the exemplary motor and blower of the present invention, the gap between the opposing surfaces in the labyrinth portion of the motor can be secured while still reducing the gap. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing an example of the configuration of a blower device. [Diagram 2] FIG. 2 is a perspective view showing the appearance of the blower. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of a portion III enclosed by a dashed line in FIG. [Figure 4] FIG. 4 is an enlarged cross-sectional view of a portion IV enclosed by a dashed line in FIG. [Diagram 5] FIG. 5 is an enlarged cross-sectional view of a portion V enclosed by a dashed line in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Exemplary embodiments are described below with reference to the drawings.

[0011] In this specification, the direction parallel to the central axis CA of the blower 100 and the motor 101 is referred to as the "axial direction." Within the axial direction, the direction from the base 32 to the rotor hub 11, which will be described later, is referred to as the "one axial direction Da," and the direction from the rotor hub 11 to the base 32 is referred to as the "other axial direction Db." Additionally, the direction perpendicular to the central axis CA is referred to as the "radial direction," and the rotation direction about the central axis CA is referred to as the "circumferential direction." Within the radial direction, the direction approaching the central axis CA is referred to as the "radial inward direction Di," and the direction away from the central axis CA is referred to as the "radial outward direction Do."

[0012] In this specification, "annular" refers not only to a shape that is continuous and uninterrupted throughout the entire circumferential area centered on the central axis CA, but also to a shape that has one or more interruptions in a portion of the entire area centered on the central axis CA. It also refers to a shape that describes a closed curve on a curved surface that intersects with the central axis CA.

[0013] In addition, in the positional relationship between any one of a direction, a line, and a plane and any other, "parallel" includes not only a state in which the two do not intersect at all no matter how far they are extended, but also a state in which they are substantially parallel. Furthermore, "perpendicular" and "orthogonal" each include not only a state in which the two intersect at 90 degrees, but also a state in which they are substantially perpendicular and a state in which they are substantially orthogonal, respectively. In other words, "parallel," "perpendicular," and "orthogonal" each include a state in which there is an angle deviation in the positional relationship between the two to an extent that does not deviate from the gist of the present invention.

[0014] Note that these are names used merely for the purpose of explanation, and are not intended to limit the actual positional relationships, directions, names, and the like.

[0015] <1. Embodiment> Fig. 1 is a cross-sectional view showing an example of the configuration of blower device 100. Fig. 2 is a perspective view showing the appearance of blower device 100. Fig. 1 shows a cross-sectional structure in a case where blower device 100 is virtually cut along a plane including a two-dot chain line II and a central axis CA in Fig. 2.

[0016] <1-1. Blower device 100> The blower 100 of this embodiment is an axial fan that draws in air from one axial direction Da and sends it out to the other axial direction Db. However, this example does not exclude a configuration in which the blower 100 is a fan other than an axial fan. For example, the blower 100 may be a blower fan or a centrifugal fan.

[0017] 1 and 2, the blower 100 includes a motor 101 and a rotor blade 102. The rotor blade 102 is rotatable about a central axis CA together with a rotor 1 (described later) of the motor 101. In this embodiment, a plurality of the rotor blades 102 are arranged on the radially outer surface of the rotor 1 and are aligned in the circumferential direction. When the motor 101 rotates the rotor blades 102 in the circumferential direction, an airflow flows in the axial direction.

[0018] The blower 100 further includes a cylindrical housing 103 and a rib 104. The cylindrical housing 103 extends in the axial direction and surrounds the motor 101 and the rotor blades 102. The cylindrical housing 103 faces the motor 101 in the radial direction with a gap therebetween, and forms an air tunnel in which the airflow flows in the space between the cylindrical housing 103 and the motor 101. The ribs 104 extend at least in the radial direction, and are arranged in a line in the circumferential direction on the other axial direction Db side of the air tunnel. The ribs 104 function as stator blades that straighten the airflow flowing through the air tunnel. The ribs 104 also connect the base portion 32 of the motor 101 to the other axial end portion of the cylindrical housing 103. That is, the radial inner end portion of the rib 104 is connected to the base portion 32. The radial outer end portion of the rib 104 is connected to the radial inner side surface of the cylindrical housing 103.

[0019] As described later, in the blower 100 of this embodiment, the gap between the opposing surfaces fi, fo in the labyrinth portion 5 of the motor 101 can be secured while the gap can be made smaller. Therefore, the intrusion of water and dust from the radially outer Do side to the radially inner Di side of the labyrinth portion 5 can be suppressed or prevented.

[0020] <1-2.Motor 101> Next, a configuration example of the motor 101 will be described with reference to Fig. 1 to Fig. 4. Fig. 3 is an enlarged cross-sectional view of a portion III surrounded by a dashed line in Fig. 1. Fig. 4 is an enlarged cross-sectional view of a portion IV surrounded by a dashed line in Fig. 1.

[0021] As shown in FIG. 1, a motor 101 includes a rotor 1, a stator 2, a housing 3, a circuit board 4, a labyrinth portion 5, and a water-repellent layer 6.

[0022] <1-2-1.Rotor 1> The rotor 1 is rotatable about a central axis CA extending in the axial direction. As described above, the motor 101 includes the rotor 1. The rotor 1 has a shaft 10, a rotor hub 11, a protruding wall portion 12, a rotor lid portion 13, a rotor cylinder portion 14, a first circumferential wall portion 15, and a magnet 16.

[0023] The shaft 10 extends in the axial direction along the central axis CA, and is rotatably supported by the bearings 311. As described above, the rotor 1 has the shaft 10. The shaft 10 is rotatable about the central axis CA. That is, in this embodiment, the shaft 10 is a rotating shaft. However, without being limited to this example, the shaft 10 may be a fixed shaft fixed together with the stator 2, or may be unable to rotate around the central axis CA. If it is a fixed shaft, a bearing is disposed between the shaft 10 and the rotor hub 11, which rotatably supports the rotor hub 11 relative to the shaft 10.

[0024] 1, in this embodiment, the rotor hub 11 is fixed to one axial end of the shaft 10. As described above, the rotor 1 has the rotor hub 11. The rotor hub 11 extends radially outward Do from one axial end of the shaft 10.

[0025] The protruding wall portion 12 is a metallic cylindrical member extending in the axial direction, and surrounds the central axis CA. As described above, the rotor 1 has the protruding wall portion 12. The cylindrical protruding wall portion 12 extends from the other axial end face of the rotor hub 11 in the other axial direction Db, and surrounds one axial end of the bearing 311. In this embodiment, the protruding wall portion 12 is integral with the rotor hub 11. However, the present invention is not limited to this example, and the protruding wall portion 12 may be a separate member from the rotor hub 11.

[0026] The rotor lid portion 13 is disposed on one axial side Da from the stator 2 and extends in the radial direction. As described above, the rotor 1 has the rotor lid portion 13. In detail, the rotor lid portion 13 is annular and surrounds the rotor hub 11, and extends from the radial outer end portion of the rotor hub 11 in the radial outward direction Do.

[0027] The rotor cylinder portion 14 is a cylindrical member extending in the axial direction, and is made of resin in this embodiment. However, this is not limited to this example. The rotor cylinder portion 14 may be made of metal. The rotor cylinder portion 14 extends from the radial outer end of the rotor lid portion 13 in the other axial direction Db. As described above, the rotor 1 has the rotor cylinder portion 14. In this embodiment, the rotor cylinder portion 14 is a cylindrical truncated cone shape surrounding the stator 2, and in FIG. 1, it expands radially outward Do as it approaches the other axial direction Db. However, this is not limited to this example, and the rotor cylinder portion 14 may be a cylindrical shape extending in the axial direction.

[0028] In this embodiment, a plurality of rotor blades 102 are arranged on the radially outer side surface of the rotor cylinder portion 14. That is, the rotor 1 has a plurality of rotor blades 102. The plurality of rotor blades 102 each extend radially outward Do from the radially outer side surface of the rotor cylinder portion 14, and extend at least in the axial direction. The rotor cylinder portion 14, the rotor cover portion 13, and the plurality of rotor blades 102 are integral with each other and constitute a single member. However, this is not limited to the example, and at least one of the rotor blades 102, the rotor cover portion 13, and the rotor cylinder portion 14 may be separate bodies. The plurality of rotor blades 102 may also be separate members from the rotor 1. For example, the motor 101 may have an impeller. This impeller may have an impeller base and a plurality of rotor blades 102. The impeller base may be a covered cylindrical shape extending in the axial direction and opening to the other axial direction Db, and may be attached to one axial end of the rotor 1. A number of rotor blades 102 may be disposed on the radially outer surface of the impeller base and aligned in the circumferential direction.

[0029] The first peripheral wall portion 15 is a metallic cylindrical member extending in the axial direction and surrounds the central axis CA. In this embodiment, the first peripheral wall portion 15 is a cylindrical magnetic body extending in the axial direction. As described above, the rotor 1 has the first peripheral wall portion 15. The cylindrical first peripheral wall portion 15 extends from the other axial end face of the rotor cover portion 13 in the other axial direction Db to surround the stator 2. However, this is not limited to the example, and the first peripheral wall portion 15 may extend from the radial inner side surface of the rotor cylinder portion 14 in the other axial direction Db. That is, the portion of the first peripheral wall portion 15 on the one axial direction Da side is connected to either the other axial end portion of the rotor cover portion 13 or the radial inner end portion of the rotor cylinder portion 14. For example, the portion of the first peripheral wall portion 15 on the one axial direction Da side is integrally formed with at least one of the rotor cover portion 13 and the rotor cylinder portion 14 by insert molding or the like. 1 and 3, the portion on one axial direction Da of the first circumferential wall portion 15 may be embedded in either the rotor cover portion 13 or the rotor cylindrical portion 14. Alternatively, the portion on one axial direction Da of the first circumferential wall portion 15 may be inserted into a cylindrical radial inner end portion of the rotor cylindrical portion 14 and fixed to the cylindrical radial inner end portion of the rotor cylindrical portion 14 by means of press-fitting, adhesion, or the like.

[0030] The magnet 16 is disposed on the radially inner surface of the first circumferential wall portion 15 and faces the stator 2 (particularly the stator core 21 described later) in the radial direction. As described above, the rotor 1 has the magnet 16. The magnet 16 is disposed radially outward Do of the stator 2 (particularly the stator core 21) and surrounds the stator 2 (particularly the stator core 21). In the magnet 16, different magnetic poles (south poles, north poles) are alternately arranged in the circumferential direction.

[0031] As shown in FIG. 4, preferably, the axial length L1 of the portion of the first peripheral wall portion 15 exposed from either the rotor lid portion 13 or the rotor cylinder portion 14 is longer than the axial length L2 of the portion connected to either of the portions.

[0032] In this way, the axial length L1 of the exposed portion of the first circumferential wall portion 15 of the magnetic body can be made longer. Therefore, the first circumferential wall portion 15 can more easily dissipate heat transferred from the magnet 16. This improves the heat dissipation performance of the magnet 16.

[0033] Furthermore, the axial width W (see FIG. 4) of the pair of third opposing surfaces fi3, fo3 can be made longer. Therefore, the third water-repellent layer 63, which will be described later, can be disposed in a desired region of the third opposing surfaces fi3, fo3 in the axial direction, increasing the degree of freedom in the layout of the arrangement position of the third water-repellent layer 63. Alternatively, the axial width W of the third water-repellent layer 63 can be made wider. Therefore, the effect of suppressing or preventing the intrusion of water and dust into the inside of the motor 101 (particularly the stator 2) can be further improved.

[0034] <1-2-2. Stator 2> The stator 2 rotates the rotor 1 by magnetic flux generated by energization. As shown in FIG.

[0035] The stator core 21 is an annular magnetic body surrounding the central axis CA, and in this embodiment is a laminated body in which plate-shaped electromagnetic steel sheets extending in the radial direction are stacked in the axial direction. The stator core 21 is fixed to the radially outer surface of the stator holder 31. The stator core 21 also has slots (not shown). The slots penetrate the stator core 21 in the axial direction and are arranged in multiple slots in the circumferential direction. The stator core 21 has multiple coil portions 23 arranged in the circumferential direction. As described above, the stator 2 has the stator core 21.

[0036] The insulators 22 have electrical insulation properties and are arranged on the surfaces of the stator core 21 (particularly, both axial end faces and inner surfaces of the slots, etc.).

[0037] The coil portion 23 is a member in which a conductor wire (reference number omitted) is arranged in a coil shape on the stator core 21 via the insulator 22. The conductor wire is, for example, an enamel-coated copper wire, a metal wire coated with an electrical insulating material, or the like, and the coil portion 23 is formed by being wound around teeth (not shown) between circumferentially adjacent slots of the stator core 21. When a driving current is supplied to each coil portion 23, the stator 2 is excited to drive the rotor 1.

[0038] <1-2-3. Housing 3> The housing 3 has a stator holder 31 , a base portion 32 , and a second circumferential wall portion 33 .

[0039] The stator holder 31 is a metallic cylindrical member extending in the axial direction and surrounding the central axis CA. The stator holder 31 extends in the axial direction and supports the stator core 21. As described above, the housing 3 has the stator holder 31. In other words, the motor 101 has the stator holder 31. The stator holder 31 is cylindrical and extends in the axial direction surrounding the central axis CA, and holds the stator core 21 on its radially outer surface.

[0040] Moreover, one axial end of the stator holder 31 is disposed radially outward Do from the protruding wall portion 12 of the rotor 1. The protruding wall portion 12 (particularly the portion on the other axial side Db) is inserted inside (radially inward) one axial end of the stator holder 31 and faces the one axial end of the stator holder 31 in the radial direction with a gap therebetween.

[0041] Furthermore, a bearing 311 is disposed on the cylindrical inner peripheral surface (that is, the radially inner surface) of the stator holder 31, and the shaft 10 is inserted through the bearing 311. The stator holder 31 supports the shaft 10 via the bearing 311 so that the shaft 10 is rotatable.

[0042] The bearing 311 is disposed on the inner circumferential surface (i.e., the radially inner surface) of the stator holder 31. The motor 101 includes the bearing 311. The bearing 311 is a metallic cylindrical member that extends in the axial direction and surrounds the shaft 10, and is a sleeve that functions as a fluid dynamic bearing in this embodiment. A fluid (not shown) such as a lubricating oil is disposed between the shaft 10 and the bearing 311. A dynamic pressure groove (not shown) for generating dynamic pressure in the fluid interposed between the shaft 10 and the bearing 311 is disposed on at least one of the radially outer surface of the shaft 10 and the radially inner surface of the bearing 311. When the shaft 10 rotates, the dynamic pressure groove generates dynamic pressure in the fluid between the two. This dynamic pressure separates the bearing 311 and the shaft 10. As a result, the rotating shaft 10 is supported in a non-contact state with the bearing 311.

[0043] One axial end of the bearing 311 is cut out in an annular shape at its radially outer end. In other words, the bearing 311 has a recess 312. The recess 312 is cylindrical and surrounds the central axis CA, and extends in the axial direction. As shown in FIG. 3, the recess 312 is recessed toward the other axial direction Db at one axial end of the bearing 311, and opens toward the radially outward Do. The other axial end face of the recess 312 (i.e., the inner surface facing the one axial direction Da) is disposed closer to the other axial direction Db than the protruding wall portion 12, and faces the other axial end face of the protruding wall portion 12 with a gap therebetween in the axial direction.

[0044] In addition, the radially inner surface of the recess 312 (i.e., the inner surface facing radially outward Do) is positioned radially inward Di of the protruding wall portion 12 of the rotor 1 and radially faces the radially inner surface of the protruding wall portion 12 with a gap therebetween.

[0045] Moreover, the bearing 311 has a tip portion 313. The tip portion 313 is a portion of one axial end portion of the bearing 311 on the radially inward Di side of the recess 312 (i.e., a portion that is not cut out). The tip portion 313 is a metallic cylindrical member that extends in the axial direction and surrounds the shaft 10. The tip portion 313 is disposed radially inward Di of the protruding wall portion 12 of the rotor 1, and faces the protruding wall portion 12 in the radial direction with a gap therebetween. The radially outer surface of the tip portion 313 can be rephrased as the radially inner surface of the recess 312 (i.e., the inner surface facing the radially outward Do). Moreover, the tip portion 313 is a part of the bearing 311 in this embodiment. However, the present invention is not limited to this example, and the tip portion 313 may be a member separate from the bearing 311 and disposed on the radially inward Di side of one axial end face of the bearing 311.

[0046] Note that, without being limited to the example of this embodiment, one axial end of the stator holder 31 may be disposed radially inward Di from the protruding wall portion 12 of the rotor 1. In other words, one axial end of the stator holder 31 may be inserted inside (radially inward) the protruding wall portion 12 (particularly the portion on the other axial direction Db side) and surrounded by the protruding wall portion 12.

[0047] Next, the base portion 32 is disposed on the other axial side Db from the stator 2, and extends radially outward Do from the stator holder 31. As described above, the housing 3 has the base portion 32.

[0048] The second peripheral wall portion 33 is a metallic cylindrical member extending in the axial direction and surrounds the central axis CA. The second peripheral wall portion 33 extends from one axial end face of the base portion 32 in one axial direction Da to surround the stator 2. As described above, the housing 3 has the second peripheral wall portion 33. For example, a portion of the second peripheral wall portion 33 on the other axial direction Db side is integrally formed with at least the base portion 32 by insert molding or the like. Alternatively, the portion of the second peripheral wall portion 33 on the other axial direction Db side may be inserted into an annular recess disposed on one axial end face of the base portion 32 and fixed to the base portion 32 by means of press-fitting, adhesion, or the like.

[0049] The second circumferential wall portion 33 is disposed radially outward Do from the first circumferential wall portion 15. The first circumferential wall portion 15 (particularly the portion on the other axial direction Db side) is inserted inside (radially inward) the second circumferential wall portion 33 and faces the second circumferential wall portion 33 in the radial direction with a gap therebetween.

[0050] Note that, without being limited to the example of this embodiment, the second circumferential wall portion 33 may be disposed radially inward Di from the first circumferential wall portion 15 as long as it does not come into contact with the magnet 16 and the stator 2. In other words, the second circumferential wall portion 33 may be inserted inside (radially inward) the first circumferential wall portion 15 (particularly the portion on the other axial direction Db side) and surrounded by the first circumferential wall portion 15.

[0051] <1-2-4. Circuit board 4> The circuit board 4 is disposed on the other axial direction Db side of the base portion 32, radially outward Do from the stator holder 31. The circuit board 4 is electrically connected to lead wires (reference numbers omitted) drawn from the coil portion 23. A drive circuit for the stator 2 and the like are mounted on the circuit board 4. The circuit board 4 is also electrically connected to external wiring 41, and is covered with a resin covering portion 42 together with the connection end of the external wiring 41. The external wiring 41 is drawn out to the outside of the motor 101, and electrically connects the circuit board 4 to an external device, power source, and the like.

[0052] <1-2-5.Labyrinth Part 5> The labyrinth portion 5 suppresses or prevents water and dust from passing through the inside and outside of the labyrinth portion 5. The labyrinth portion 5 has a pair of metal tubular members surrounding a central axis CA. The pair of metal tubular members have a pair of opposing surfaces fi, fo, one of which surrounds the other. The pair of opposing surfaces fi, fo face each other in the radial direction with a gap therebetween.

[0053] In this way, compared to when the pair of cylindrical members are made of resin, for example, the metallic cylindrical members have good dimensional accuracy, and therefore the dimensional tolerance can be reduced. Therefore, the gap between the pair of opposing surfaces fi, fo can be secured while being made smaller. This makes it possible to suppress or prevent the intrusion of water and dust from the radially outer Do side to the radially inner Di side of the labyrinth portion 5.

[0054] The labyrinth portion 5 includes a first labyrinth portion 51, a second labyrinth portion 52, and a third labyrinth portion 53.

[0055] <1-2-5-1. First Labyrinth Section 51> 3, the first labyrinth portion 51 is formed in a gap between the protruding wall portion 12 (particularly the portion on the other axial direction Db side) and one axial end portion of the stator holder 31. Of a pair of metallic tubular members that the first labyrinth portion 51 has, one is the protruding wall portion 12 and the other is the stator holder 31. As described above, the labyrinth portion 5 includes the first labyrinth portion 51. The first labyrinth portion 51 includes a pair of first opposing surfaces fi1, fo1.

[0056] In this embodiment, the pair of first opposing surfaces fi1, fo1 is composed of the radial outer surface of the protruding wall portion 12 and the radial inner surface of one axial end of the stator holder 31 that faces the radial outer surface with a gap therebetween. In detail, the region of the radial outer surface of the protruding wall portion 12 that overlaps with the radial inner surface of one axial end of the stator holder 31 when viewed from the radial direction is called the "first opposing surface fi1". Also, the region of the radial inner surface of one axial end of the stator holder 31 that overlaps with the radial outer surface of the protruding wall portion 12 when viewed from the radial direction is called the "first opposing surface fo1". In other words, the pair of first opposing surfaces fi1, fo1 is composed of the first opposing surface fi1 of the protruding wall portion 12 and the first opposing surface fo1 of the stator holder 31.

[0057] In addition, without being limited to the example of this embodiment, one axial end of the stator holder 31 may be disposed radially inward Di from the protruding wall portion 12 of the rotor 1. In other words, one axial end of the stator holder 31 may be inserted inside (radially inward) the protruding wall portion 12 (particularly the portion on the other axial Db side). In this case, however, the second labyrinth portion 52 and second opposing surfaces fi2, fo2 described later are not disposed. In other words, the labyrinth portion 5 does not include the second labyrinth portion 52. In addition, the pair of opposing surfaces fi, fo does not include the pair of second opposing surfaces fi2, fo2. In addition, in this case, the first opposing surface fi1 becomes the radial outer surface of one axial end of the stator holder 31, and more specifically, becomes a region of the radial outer surface of one axial end of the stator holder 31 that overlaps with the radial inner surface of the protruding wall portion 12 when viewed from the radial direction. In addition, the first opposing surface fo1 is the radially inner surface of the protruding wall portion 12, and more specifically, is the area of ​​the radially inner surface of the protruding wall portion 12 that overlaps with the radially outer surface of one axial end of the stator holder 31 when viewed from the radial direction.

[0058] That is, one of the cylindrical portions of the protruding wall portion 12 and the stator holder 31 may surround the other cylindrical portion. In this case, the pair of first opposing surfaces fi1, fo1 is formed by the radially inner surface of one cylindrical portion and the radially outer surface of the other cylindrical portion. The radially inner surface of one cylindrical portion faces the radially outer surface of the other cylindrical portion with a gap therebetween.

[0059] <1-2-5-2. Second Labyrinth Section 52> The second labyrinth portion 52 is formed in a gap between the radially inner side surface of the recess 312 (i.e., the inner surface facing radially outward Do) and the radially inner side surface of the protruding wall portion 12. Of a pair of metallic tubular members that the second labyrinth portion 52 has, one is the protruding wall portion 12 and the other is the stator holder 31. As described above, the labyrinth portion 5 includes the second labyrinth portion 52. The second labyrinth portion 52 includes a pair of second opposing surfaces fi2, fo2.

[0060] The pair of second opposing surfaces fi2, fo2 is composed of the radial inner surface of the recess 312 and the radial inner surface of the protruding wall portion 12 that faces the radial inner surface with a gap therebetween. In detail, the region of the radial inner surface of the recess 312 that overlaps with the radial inner surface of the protruding wall portion 12 when viewed from the radial direction is called the "second opposing surface fi2". Also, the region of the radial inner surface of the protruding wall portion 12 that overlaps with the radial inner surface of the recess 312 when viewed from the radial direction is called the "second opposing surface fo2". In other words, the pair of second opposing surfaces fi2, fo2 is composed of the second opposing surface fi2 of the recess 312 and the second opposing surface fo2 of the protruding wall portion 12.

[0061] <1-2-5-3. Third Labyrinth Section 53> 4, the third labyrinth portion 53 is formed in a gap between the first circumferential wall portion 15 (particularly the portion on the other axial direction Db side) and the second circumferential wall portion 33. Of a pair of metallic tubular members that the third labyrinth portion 53 has, one is the first circumferential wall portion 15 and the other is the second circumferential wall portion 33. As described above, the labyrinth portion 5 includes the third labyrinth portion 53. The third labyrinth portion 53 includes a pair of third opposing surfaces fi3, fo3.

[0062] In this embodiment, the pair of third opposing surfaces fi3, fo3 is composed of the radially outer surface of the first circumferential wall portion 15 and the radially inner surface of the second circumferential wall portion 33. In detail, the region of the radially outer surface of the first circumferential wall portion 15 that overlaps with the radially inner surface of the second circumferential wall portion 33 when viewed from the radial direction is called the "third opposing surface fi3". Also, the region of the radially inner surface of the second circumferential wall portion 33 that overlaps with the radially outer surface of the first circumferential wall portion 15 when viewed from the radial direction is called the "third opposing surface fo3". In other words, the pair of third opposing surfaces fi3, fo3 is composed of the third opposing surface fi3 of the first circumferential wall portion 15 and the third opposing surface fo3 of the second circumferential wall portion 33.

[0063] In addition, without being limited to the example of this embodiment, the second circumferential wall portion 33 may be disposed radially inward Di from the first circumferential wall portion 15 as long as it does not contact the magnet 16 and the stator 2. In other words, the second circumferential wall portion 33 may be inserted inside (radially inward) the first circumferential wall portion 15 (particularly the portion on the other axial direction Db side). In this case, the third opposing surface fi3 becomes the radially outer side surface of the second circumferential wall portion 33, and more specifically, becomes a region of the radially outer side surface of the second circumferential wall portion 33 that overlaps with the radially inner side surface of the first circumferential wall portion 15 when viewed from the radial direction. In addition, the third opposing surface fo3 becomes the radially inner side surface of the first circumferential wall portion 15, and more specifically, becomes a region of the radially inner side surface of the first circumferential wall portion 15 that overlaps with the radially outer side surface of the second circumferential wall portion 33 when viewed from the radial direction.

[0064] That is, one of the first peripheral wall portion 15 and the second peripheral wall portion 33 may surround the other peripheral wall portion. In this case, the pair of third opposing surfaces fi3, fo3 is formed by a radially inner surface of one peripheral wall portion and a radially outer surface of the other peripheral wall portion. The radially inner surface of one peripheral wall portion faces the radially outer surface of the other peripheral wall portion with a gap therebetween.

[0065] Preferably, the axial width W (see FIG. 4) of the pair of third opposing surfaces fi3, fo3 is longer than the axial length L3 (see FIG. 3) of the protruding wall portion 12. The axial width W is, in detail, the width in the axial direction of the region of the radially outer side surface of the first peripheral wall portion 15 that overlaps with the radially inner side surface of the second peripheral wall portion 33 when viewed from the radial direction. In other words, the axial width W is the width in the axial direction of the region of the radially inner side surface of the second peripheral wall portion 33 that overlaps with the radially outer side surface of the first peripheral wall portion 15 when viewed from the radial direction. In this way, the axial width W of the pair of third opposing surfaces fi3, fo3 can be made wider. Therefore, the effect of suppressing or preventing the intrusion of water and dust into the inside of the motor 101 (particularly the stator 2) can be improved.

[0066] <1-2-5-4. Radial width of labyrinth portion 5> Next, the radial width of the gap between the pair of opposing surfaces fi, fo is preferably equal to or smaller than the radial width of at least one of the pair of metallic tubular members of the labyrinth portion 5, and more preferably equal to or smaller than the radial width of both of the pair of metallic tubular members. By making the radial width of the gap between the pair of opposing surfaces fi, fo small, water and dust can be more effectively suppressed or prevented from passing through the labyrinth portion 5.

[0067] 3, in the first labyrinth portion 51, the radial width Wr1 of the gap between the pair of first opposing surfaces fi1, fo1 is preferably equal to or smaller than at least one of the radial width d1 of the protruding wall portion 12 and the radial width d2 of one axial end portion of the stator holder 31, and more preferably equal to or smaller than both of the radial widths d1, d2. By making the radial width Wr1 of the gap between the pair of first opposing surfaces fi1, fo1 small, water and dust can be more effectively suppressed or prevented from passing through the first labyrinth portion 51.

[0068] 3, in the second labyrinth portion 52, the radial width Wr2 of the gap between the pair of second opposing surfaces fi2, fo2 is preferably equal to or smaller than at least one of the radial width d1 of the protruding wall portion 12 and the radial width d3 of one axial end portion (i.e., the tip portion 313) of the bearing 311, and more preferably equal to or smaller than both of the radial widths d1, d3. By making the radial width Wr2 of the gap between the pair of second opposing surfaces fi2, fo2 small, water and dust can be more effectively suppressed or prevented from passing through the second labyrinth portion 52.

[0069] 4, in the third labyrinth portion 53, the radial width Wr3 of the gap between the pair of third opposing surfaces fi3, fo3 is preferably equal to or smaller than at least one of the radial width d4 of the first circumferential wall portion 15 and the radial width d5 ​​of the second circumferential wall portion 33, and more preferably equal to or smaller than both of the radial widths d4, d5. Since the radial width Wr3 of the gap between the pair of third opposing surfaces fi3, fo3 is small, water and dust can be more effectively suppressed or prevented from passing through the third labyrinth portion 53.

[0070] <1-2-6. Water-repellent layer 6> Next, the water-repellent layer 6 will be described with reference to FIG. 1 and FIG. 3 to FIG. 4. The water-repellent layer 6 is a coating having water repellency, and is cylindrical and extends in the axial direction. In this embodiment, the water-repellent layer 6 is a coating film of a water repellent agent. In this manner, the water-repellent layer 6 can be formed by a simple means. However, the material and arrangement method of the water-repellent layer 6 are not limited to this example. The material of the water-repellent layer 6 may be any material that has water repellency, and may be, for example, a fluorine-based resin or oil, a silicone-based resin or oil, or a water-repellent ceramic. The arrangement method of the water-repellent layer 6 may be spraying, dipping, physical vapor deposition, chemical vapor deposition, or the like.

[0071] The water-repellent layer 6 is disposed on at least one of the pair of opposing surfaces fi, fo. As described above, the motor 101 includes the water-repellent layer 6. The arrangement of the water-repellent layer 6 can suppress or prevent water from passing through the gap between the pair of opposing surfaces fi, fo.

[0072] On the opposing surface fi, the cylindrical water-repellent layer 6 may be disposed in any partial region in the axial direction, or may be disposed in the entire region of the opposing surface fi. Similarly, on the opposing surface fo, the cylindrical water-repellent layer 6 may be disposed in a partial region in the axial direction, or may be disposed in the entire region in the axial direction.

[0073] Preferably, as in this embodiment, the water-repellent layer 6 is disposed on both of the pair of opposing surfaces fi, fo. In this case, the axial width of the water-repellent layer 6 disposed on the opposing surface fi may be the same as the axial width of the water-repellent layer 6 disposed on the opposing surface fo, or may be smaller or larger than the axial width of the water-repellent layer 6 disposed on the opposing surface fo. Also, as viewed from the radial direction, at least a part of the water-repellent layer 6 disposed on the opposing surface fi may or may not overlap with at least a part of the water-repellent layer 6 disposed on the opposing surface fo. That is, in the latter case, the arrangement of the water-repellent layer 6 disposed on the opposing surface fi may be shifted in the axial direction from the arrangement of the water-repellent layer 6 disposed on the opposing surface fo.

[0074] The water-repellent layer 6 includes a first water-repellent layer 61 , a second water-repellent layer 62 , and a third water-repellent layer 63 .

[0075] <1-2-6-1. First water-repellent layer 61> The first water-repellent layer 61 is a coating having water repellency, and is cylindrical and extends in the axial direction. In the first labyrinth portion 51, the first water-repellent layer 61 is disposed on at least one of the pair of first opposing surfaces fi1, fo1. As described above, the water-repellent layer 6 includes the first water-repellent layer 61. The first water-repellent layer 61 can more effectively suppress or prevent the intrusion of water into the shaft 10, the bearing 311, and the space between them. Since the pair of first opposing surfaces fi1, fo1 are the outer surfaces of the protruding wall portion 12 and one axial end of the stator holder 31, respectively, the first water-repellent layer 61 can be easily disposed before assembling the motor 101.

[0076] In the first opposing surface fi1, the cylindrical first water-repellent layer 61 may be disposed in any partial region in the axial direction as shown in Fig. 3, or may be disposed over the entire area in the axial direction. Similarly, in the first opposing surface fo1, the cylindrical first water-repellent layer 61 may be disposed in any partial region in the axial direction, or may be disposed over the entire area in the axial direction. Moreover, the cylindrical first water-repellent layer 61 may be disposed in a region other than the first opposing surface fi1 on the radial side surface (radial outer surface in Fig. 3) of the protruding wall portion 12, or may be disposed in a region other than the first opposing surface fo1 on the radial side surface (radial inner surface in Fig. 3) of one axial end of the stator holder 31.

[0077] Preferably, as shown in FIG. 3, the first water-repellent layer 61 is disposed on both of the pair of first opposing surfaces fi1, fo1. In this case, the axial width of the first water-repellent layer 61 disposed on the first opposing surface fi1 may be the same as the axial width of the first water-repellent layer 61 disposed on the first opposing surface fo1, or may be smaller or larger than the axial width of the first water-repellent layer 61 disposed on the first opposing surface fo1. Also, as viewed from the radial direction, at least a part of the first water-repellent layer 61 disposed on the first opposing surface fi1 may overlap at least a part of the first water-repellent layer 61 disposed on the first opposing surface fo1, or may not overlap. That is, in the latter case, the arrangement of the first water-repellent layer 61 on the first opposing surface fi1 may be shifted in the axial direction from the arrangement of the first water-repellent layer 61 on the first opposing surface fo1. However, this example does not exclude a configuration in which the first water-repellent layer 61 is not disposed on at least one of the pair of first opposing surfaces fi1, fo1.

[0078] <1-2-6-2. Second water-repellent layer 62> The second water-repellent layer 62 is a coating having water repellency, and has a cylindrical shape extending in the axial direction. In the second labyrinth portion 52, the second water-repellent layer 62 is disposed on at least one of the pair of second opposing surfaces fi2, fo2. As described above, the water-repellent layer 6 includes the second water-repellent layer 62. The second water-repellent layer 62 can more effectively suppress or prevent the intrusion of water into the shaft 10 and between the shaft 10 and the bearing 311. Since the pair of second opposing surfaces fi2, fo2 are the outer surfaces of the bearing 311 and the protruding wall portion 12, respectively, the second water-repellent layer 62 can be easily disposed before assembling the motor 101.

[0079] In the second opposing surface fi2, the cylindrical second water-repellent layer 62 may be disposed in any partial region in the axial direction as shown in Fig. 3, or may be disposed over the entire area in the axial direction. Similarly, in the second opposing surface fo2, the cylindrical second water-repellent layer 62 may be disposed in any partial region in the axial direction, or may be disposed over the entire area in the axial direction. In addition, the cylindrical second water-repellent layer 62 may be disposed in a region other than the second opposing surface fi2 on the radial inner side surface of the recess 312 of the bearing 311 (i.e., the radial outer side surface of the tip portion 313), or may be disposed in a region other than the second opposing surface fo2 on the radial inner side surface of the protruding wall portion 12.

[0080] Preferably, as shown in FIG. 3, the second water-repellent layer 62 is disposed on both of the pair of second opposing surfaces fi2, fo2. In this case, the axial width of the second water-repellent layer 62 disposed on the second opposing surface fi2 may be the same as the axial width of the second water-repellent layer 62 disposed on the second opposing surface fo2, or may be smaller or larger than the axial width of the second water-repellent layer 62 disposed on the second opposing surface fo2. Also, as viewed from the radial direction, at least a part of the second water-repellent layer 62 disposed on the second opposing surface fi2 may overlap at least a part of the second water-repellent layer 62 disposed on the second opposing surface fo2, or may not overlap. That is, in the latter case, the arrangement of the second water-repellent layer 62 on the second opposing surface fi2 may be shifted in the axial direction from the arrangement of the second water-repellent layer 62 on the second opposing surface fo2. However, this example does not exclude a configuration in which the second water-repellent layer 62 is not disposed on at least one of the pair of second opposing surfaces fi2, fo2.

[0081] <1-2-6-3.Third water-repellent layer 63> The third water-repellent layer 63 is a coating having water repellency, and has a cylindrical shape extending in the axial direction. In the third labyrinth portion 53, the third water-repellent layer 63 is disposed on at least one of the pair of third opposing surfaces fi3, fo3. As described above, the water-repellent layer 6 includes the third water-repellent layer 63. The third water-repellent layer 63 can more effectively suppress or prevent the intrusion of water into the inside of the motor 101 (particularly the stator 2). In addition, by forming the third water-repellent layer 63 on at least one of the third opposing surfaces fi3, fo3 before assembling the motor 101, the third water-repellent layer 63 can be easily disposed.

[0082] In the third opposing surface fi3, the cylindrical third water-repellent layer 63 may be disposed in any partial region in the axial direction as shown in Fig. 4, or may be disposed over the entire area in the axial direction. Similarly, in the third opposing surface fo3, the cylindrical third water-repellent layer 63 may be disposed in any partial region in the axial direction, or may be disposed over the entire area in the axial direction. Moreover, the cylindrical third water-repellent layer 63 may be disposed in a region of the radial side surface (radial outer surface in Fig. 4) of the first circumferential wall portion 15 other than the third opposing surface fi3, or may be disposed in a region of the radial side surface (radial inner surface in Fig. 4) of the second circumferential wall portion 33 other than the third opposing surface fo3.

[0083] Preferably, as shown in FIG. 4, the third water-repellent layer 63 is disposed on both of the pair of third opposing surfaces fi3, fo3. In this case, the axial width of the third water-repellent layer 63 disposed on the third opposing surface fi3 may be the same as the axial width of the third water-repellent layer 63 disposed on the third opposing surface fo3, or may be smaller or larger than the axial width of the third water-repellent layer 63 disposed on the third opposing surface fo3. Also, as viewed from the radial direction, at least a part of the third water-repellent layer 63 disposed on the third opposing surface fi3 may overlap at least a part of the third water-repellent layer 63 disposed on the third opposing surface fo3, or may not overlap. That is, in the latter case, the arrangement of the third water-repellent layer 63 on the third opposing surface fi3 may be shifted in the axial direction from the arrangement of the third water-repellent layer 63 on the third opposing surface fo3. However, this example does not exclude a configuration in which the third water-repellent layer 63 is not disposed on at least one of the pair of third opposing surfaces fi3, fo3.

[0084] <1-2-7. Other labyrinth parts> 1 and 5, the motor 101 further includes an outer labyrinth portion 54 and an outer water-repellent layer 64. Note that Fig. 5 is an enlarged cross-sectional view of a portion V surrounded by a dashed line in Fig. 1.

[0085] <1-2-7-1.Outer labyrinth part 54> The outer labyrinth portion 54 is formed between the second circumferential wall portion 33 and the rotor tubular portion 14. The outer labyrinth portion 54 has a pair of cylindrical members surrounding the central axis CA. Of the pair of cylindrical members, one is the second circumferential wall portion 33 made of metal, and the other is the rotor tubular portion 14 made of resin. The pair of cylindrical members has a pair of outer facing surfaces foa, fob, one of which surrounds the other. The pair of outer facing surfaces foa, fob face each other in the radial direction with a gap therebetween. The outer labyrinth portion 54 includes a pair of outer facing surfaces foa, fob. In this embodiment, the pair of outer facing surfaces foa, fob are composed of the radial outer surface of the second circumferential wall portion 33 and the radial inner surface of the rotor tubular portion 14. In detail, the region of the radial outer surface of the second circumferential wall portion 33 that overlaps with the radial inner surface of the rotor tubular portion 14 when viewed from the radial direction is called the "outer facing surface foa". In addition, the region of the radially inner surface of the second circumferential wall portion 33 that overlaps with the radially inner surface of the rotor cylindrical portion 14 when viewed from the radial direction is referred to as the “outer facing surface fob.” In other words, the pair of outer facing surfaces foa, fob is composed of the outer facing surface foa of the second circumferential wall portion 33 and the outer facing surface fob of the rotor cylindrical portion 14.

[0086] 5, the minimum radial width Wr4 in the gap between the pair of outer opposing surfaces foa, fob is preferably equal to or smaller than at least one of the radial width d5 ​​of the second circumferential wall portion 33 and the thickness d6 of the rotor tubular portion 14, and more preferably equal to or smaller than both of the widths d5, d6. The thickness d6 of the rotor tubular portion 14 is the width in a direction perpendicular to the direction in which the rotor tubular portion 14 extends as viewed from the circumferential direction. In this way, the radial width Wr4 between the pair of outer opposing surfaces foa, fob can be made narrower, and therefore water and dust can be more effectively suppressed or prevented from passing through the outer labyrinth portion 54.

[0087] <1-2-7-2.Outer water repellent layer 64> The outer water-repellent layer 64 is a coating having water repellency, and has a cylindrical shape extending in the axial direction. In this embodiment, the outer water-repellent layer 64 is a coating film of a water repellent agent. In this manner, the outer water-repellent layer 64 can be formed by a simple means. However, the material and arrangement method of the outer water-repellent layer 64 are not limited to this example. The material of the outer water-repellent layer 64 may be any material that has water repellency, and may be, for example, a fluorine-based resin or oil, a silicone-based resin or oil, or a water-repellent ceramic. The arrangement method of the outer water-repellent layer 64 may be spraying, dipping, physical vapor deposition, chemical vapor deposition, or the like.

[0088] In the outer labyrinth portion 54, the outer water-repellent layer 64 is disposed on at least one of the pair of outer facing surfaces foa, fob. In this embodiment, as shown in FIG. 5, the outer water-repellent layer 64 is disposed on the outer facing surface foa of the second circumferential wall portion 33, but is preferably disposed on both of the pair of outer facing surfaces foa, fob. The outer water-repellent layer 64 can more effectively prevent water from entering the motor 101 from the outside to the inside. In addition, since the pair of outer facing surfaces foa, fob are the outer surfaces of the second circumferential wall portion 33 and the rotor cylinder portion 14, respectively, the outer water-repellent layer 64 can be easily disposed before assembling the motor 101.

[0089] On the outer facing surface foa, the cylindrical outer water-repellent layer 64 may be disposed in any partial region in the axial direction as shown in Fig. 5, or may be disposed over the entire region in the axial direction. Similarly, on the outer facing surface fob, the cylindrical outer water-repellent layer 64 may be disposed in any partial region in the axial direction, or may be disposed over the entire region in the axial direction. Moreover, the cylindrical outer water-repellent layer 64 may be disposed in a region of the radially outer side surface of the second circumferential wall portion 33 other than the outer facing surface foa, or may be disposed in a region of the radially inner side surface of the rotor cylinder portion 14 other than the outer facing surface fob.

[0090] In addition, when the outer water-repellent layer 64 is disposed on both of the pair of outer facing surfaces foa and fob, the axial width of the outer water-repellent layer 64 disposed on the outer facing surface foa may be the same as the axial width of the outer water-repellent layer 64 disposed on the outer facing surface fob, or may be smaller or larger than the axial width of the outer water-repellent layer 64 disposed on the outer facing surface fob. In addition, as viewed from the radial direction, at least a part of the outer water-repellent layer 64 disposed on the outer facing surface foa may or may not overlap with at least a part of the outer water-repellent layer 64 disposed on the outer facing surface fob. That is, in the latter case, the arrangement of the outer water-repellent layer 64 on the outer facing surface foa may be shifted in the axial direction from the arrangement of the outer water-repellent layer 64 on the outer facing surface fob.

[0091] However, the above example does not exclude a configuration in which the outer water-repellent layer 64 is not disposed on both of the pair of outer facing surfaces foa, fob. For example, the outer water-repellent layer 64 may be omitted.

[0092] <2.Other> The embodiments of the present invention have been described above. Note that the scope of the present invention is not limited to the above-described embodiments. The present invention can be implemented by adding various modifications to the above-described embodiments without departing from the spirit of the invention. Furthermore, the matters described in the above-described embodiments can be appropriately combined in any manner as long as no contradiction occurs.

[0093] <3. Summary> The embodiments described thus far will be summarized below.

[0094] For example, the motors disclosed herein may include: a rotor rotatable about a central axis extending in an axial direction; a stator having a stator core in which a plurality of coil portions are arranged in a circumferential direction; a labyrinth portion having a pair of metallic cylindrical members surrounding the central axis; Equipped with The pair of metallic tubular members have a pair of opposing surfaces that face each other in the radial direction with a gap therebetween, one surrounding the other (first configuration).

[0095] The motor of the first configuration is as follows: A radial width of the gap between the pair of opposing surfaces may be equal to or smaller than the radial width of at least one of the pair of metal tubular members (second configuration).

[0096] In addition, the motor of the first or second configuration has The device may further include a water-repellent layer disposed on at least one of the pair of opposing surfaces (third configuration).

[0097] The motor of the third configuration is as follows: The rotor further includes a stator holder that is cylindrical and extends in an axial direction to surround the central axis and supports the stator core. The rotor is a shaft extending along the central axis and rotatable about the central axis; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having one of the cylindrical portions of the protruding wall portion and the stator holder surrounds the other cylindrical portion, The labyrinth portion has a first labyrinth portion including a pair of first opposing surfaces, the pair of opposing surfaces includes a pair of the first opposing surfaces, The pair of first opposing surfaces are formed of a radially inner surface of one of the cylindrical portions and a radially outer surface of the other of the cylindrical portions, a radially inner surface of the one cylindrical portion radially faces a radially outer surface of the other cylindrical portion with a gap therebetween; The water-repellent layer may be configured (fourth configuration) to include a first water-repellent layer disposed on at least one of the pair of first opposing surfaces.

[0098] Moreover, the motor of the third or fourth configuration is a stator holder having a cylindrical shape extending in an axial direction and surrounding the central axis, the stator holder supporting the stator core; A bearing disposed on an inner peripheral surface of the stator holder; Further equipped with The bearing has a cylindrical recess surrounding the central shaft, The recess is recessed in the other axial direction at one end of the bearing and opens radially outward, The rotor is a shaft extending along the central axis and rotatably supported by the bearing; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having the labyrinth portion has a second labyrinth portion including a pair of second opposing surfaces, the pair of opposing surfaces includes a pair of the second opposing surfaces, The pair of second opposing surfaces are composed of a radially inner surface of the recess and a radially inner surface of the protruding wall portion that faces the radially inner surface with a gap therebetween, The water-repellent layer may be configured (fifth configuration) to include a second water-repellent layer disposed on at least one of the pair of second opposing surfaces.

[0099] In addition, the motor having any one of the third to fifth configurations is a housing having a stator holder extending in an axial direction and supporting the stator core; The rotor is a rotor cover portion disposed on one side of the stator in the axial direction and extending in the radial direction; a cylindrical first peripheral wall portion extending in the other axial direction from the other axial end surface of the rotor lid portion and surrounding the stator; having The housing includes: a base portion disposed on the other side of the stator in the axial direction and extending radially outward from the stator holder; a second peripheral wall portion extending in one axial direction from one axial end face of the base portion and surrounding the stator; and One of the first peripheral wall portion and the second peripheral wall portion surrounds the other peripheral wall portion, the labyrinth portion has a third labyrinth portion including a pair of third opposing surfaces, the pair of opposing surfaces includes a pair of the third opposing surfaces, The pair of third opposing surfaces are formed by a radially inner surface of one of the peripheral wall portions and a radially outer surface of the other of the peripheral wall portions, a radially inner surface of the one peripheral wall portion radially faces a radially outer surface of the other peripheral wall portion with a gap therebetween; The water-repellent layer may be configured (sixth configuration) to include a third water-repellent layer disposed on at least one of the pair of third opposing surfaces.

[0100] The motor of the sixth configuration is as follows: A bearing is further provided on an inner circumferential surface of the stator holder. The rotor is a shaft extending along the central axis and rotatably supported by the bearing; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having The axial width of the pair of third opposing surfaces may be longer than the axial length of the projecting wall portion (seventh configuration).

[0101] In addition, the motor of the sixth or seventh configuration is The rotor is a rotor cylinder portion extending in the other axial direction from a radial outer end portion of the rotor lid portion; a magnet disposed on a radially inner surface of the first circumferential wall portion and facing the stator core in a radial direction; and The first peripheral wall portion is a cylindrical magnetic body extending in the axial direction, a portion on one axial side of the first peripheral wall portion is connected to one of the other axial end portion of the rotor lid portion and a radially inner end portion of the rotor cylindrical portion, The first circumferential wall portion may have an axial length of a portion exposed from either of the regions longer than an axial length of a portion connected to either of the regions (eighth configuration).

[0102] In addition, the motor having any one of the third to eighth configurations is The water-repellent layer may be a coating film of a water-repellent agent (ninth configuration).

[0103] The blower device disclosed in the present specification further comprises: A motor having any one of the first to ninth configurations; a rotor blade rotatable about the central axis together with the rotor of the motor; The tenth configuration is as follows: [Industrial Applicability]

[0104] The present invention is useful as a technique for preventing the intrusion of water and dust into the inside of a motor. [Explanation of symbols]

[0105] 100 blower, 101 motor, 102 rotor blade, 103 cylindrical housing, 104 rib, 1 rotor, 10 shaft, 11 rotor hub, 12 protruding wall portion, 13 rotor cover portion, 14 rotor cylinder portion, 15 first peripheral wall portion, 16 magnet, 2 stator, 21 stator core, 22 insulator, 23 coil portion, 3 housing, 31 stator holder, 311 bearing, 312 recess, 313 tip portion, 32 base portion, 33 second peripheral wall portion, 4 circuit board, 41 ...external wiring, 42...coating portion, 6...water-repellent layer, 61...first water-repellent layer, 62...second water-repellent layer, 63...third water-repellent layer, 64...outer water-repellent layer, 5...labyrinth portion, 51...first labyrinth portion, 52...second labyrinth portion, 53...third labyrinth portion, 54...outer labyrinth portion, fi,fo...facing surfaces, fi1,fo1...first facing surfaces, fi2,fo2...second facing surfaces, fi3,fo3...third facing surfaces, foa,fob...outer facing surfaces, CA...central axis, Da...axial direction on one side, Db...axial direction on the other side, Di...radial inward, Do...radial outward

Claims

1. a rotor rotatable about a central axis extending in an axial direction; a stator having a stator core in which a plurality of coil portions are arranged in a circumferential direction; a labyrinth portion having a pair of metallic cylindrical members surrounding the central axis; Equipped with The pair of metallic cylindrical members have a pair of opposing surfaces that face each other in the radial direction with a gap between them, one surrounding the other.

2. The motor according to claim 1 , wherein a radial width of the gap between the pair of opposing surfaces is equal to or smaller than a radial width of at least one of the pair of metal tubular members.

3. The motor according to claim 1 , further comprising a water-repellent layer disposed on at least one of the pair of opposing surfaces.

4. The rotor further includes a stator holder that is cylindrical and extends in an axial direction to surround the central axis and supports the stator core. The rotor is a shaft extending along the central axis and rotatable about the central axis; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having one of the cylindrical portions of the protruding wall portion and the stator holder surrounds the other cylindrical portion, The labyrinth portion has a first labyrinth portion including a pair of first opposing surfaces, The pair of opposing surfaces includes a pair of the first opposing surfaces, The pair of first opposing surfaces are formed of a radially inner surface of the one cylindrical portion and a radially outer surface of the other cylindrical portion, a radially inner surface of the one cylindrical portion radially faces a radially outer surface of the other cylindrical portion with a gap therebetween; The motor according to claim 3 , wherein the water-repellent layer includes a first water-repellent layer disposed on at least one of the pair of first opposing surfaces.

5. a stator holder having a cylindrical shape extending in an axial direction and surrounding the central axis, the stator holder supporting the stator core; A bearing disposed on an inner peripheral surface of the stator holder; Further equipped with The bearing has a cylindrical recess surrounding the central shaft, The recess is recessed in the other axial direction at one end of the bearing and opens radially outward, The rotor is a shaft extending along the central axis and rotatably supported by the bearing; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having the labyrinth portion has a second labyrinth portion including a pair of second opposing surfaces, the pair of opposing surfaces includes a pair of the second opposing surfaces, The pair of second opposing surfaces are composed of a radially inner surface of the recess and a radially inner surface of the protruding wall portion that faces the radially inner surface with a gap therebetween, The motor according to claim 3 , wherein the water-repellent layer includes a second water-repellent layer disposed on at least one of the pair of second opposing surfaces.

6. a housing having a stator holder extending in an axial direction and supporting the stator core; The rotor is a rotor cover portion disposed on one side of the stator in the axial direction and extending in the radial direction; a cylindrical first peripheral wall portion extending in the other axial direction from the other axial end surface of the rotor lid portion and surrounding the stator; having The housing includes: a base portion disposed on the other side of the stator in the axial direction and extending radially outward from the stator holder; a second peripheral wall portion extending in one axial direction from one axial end face of the base portion and surrounding the stator; and One of the first peripheral wall portion and the second peripheral wall portion surrounds the other peripheral wall portion, the labyrinth portion has a third labyrinth portion including a pair of third opposing surfaces, the pair of opposing surfaces includes a pair of the third opposing surfaces, The pair of third opposing surfaces are formed by a radially inner surface of one of the peripheral wall portions and a radially outer surface of the other peripheral wall portion, a radially inner surface of the one peripheral wall portion radially faces a radially outer surface of the other peripheral wall portion with a gap therebetween; The motor according to claim 3 , wherein the water-repellent layer includes a third water-repellent layer disposed on at least one of the pair of third opposing surfaces.

7. A bearing is further provided on an inner circumferential surface of the stator holder. The rotor is a shaft extending along the central axis and rotatably supported by the bearing; a rotor hub extending radially outward from one axial end of the shaft; a cylindrical protruding wall portion extending in the other axial direction from the other axial end surface of the rotor hub and surrounding one axial end portion of the bearing; having The motor according to claim 6 , wherein an axial width of the pair of third opposing surfaces is longer than an axial length of the protruding wall portion.

8. The rotor is a rotor cylinder portion extending in the other axial direction from a radial outer end portion of the rotor lid portion; a magnet disposed on a radially inner surface of the first circumferential wall portion and facing the stator core in a radial direction; and The first peripheral wall portion is a cylindrical magnetic body extending in the axial direction, a portion on one axial side of the first peripheral wall portion is connected to one of the other axial end portion of the rotor lid portion and a radial inner end portion of the rotor cylindrical portion, The motor according to claim 6 , wherein an axial length of the first circumferential wall portion that is exposed from either one of the regions is longer than an axial length of a portion of the first circumferential wall portion that is connected to either one of the regions.

9. The motor according to claim 3 , wherein the water-repellent layer is a coating of a water-repellent agent.

10. A motor according to any one of claims 1 to 9; a rotor blade rotatable about the central axis together with the rotor of the motor; A blower device comprising:

Images