Motor, blower, and method of manufacturing the motor

Abstract

To provide a motor which can be manufactured with a simple work and has waterproofness and dust-proofness.SOLUTION: A motor has: a shaft 21; a cylindrical bearing housing 22 rotatably supporting the shaft 21 through a bearing 211; a casing 23 for holding an upper end of the outer peripheral surface of the bearing housing 22; a stator 24 stored in the casing 23; a rotor 25; a cover part 26 covering an opening 230 formed on the lower end of a cylinder part 231 of the casing 23; and a resin part 60 covering the stator 24 in a space surrounded by the bearing housing 22, the casing 23 and the cover part 26. The cover part 26 has an annular base 261, and a bush 262 which is arranged inside the base 261 in a radial direction and is fixed to the lower end of the outer peripheral surface of the bearing housing 22.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a motor, a blower using the motor, and a method for manufacturing the motor. [Background technology]

[0002] The motor included in a conventional fan includes a casing, a stator housed within the casing, and a base connected to the casing. The stator is placed in the space formed by the casing and the base. Resin is injected through a notch in the base to form a filler. The inclusion of the filler provides waterproof and dustproof properties (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-174896 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the resin is poured in through a notch in the base, it may be difficult for the resin to flow in, resulting in areas that are not filled, which may reduce waterproof and dustproof properties.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a motor that can be manufactured with simple operations and that is waterproof and dustproof.

[0006] Another object of the present invention is to provide a blower that can be manufactured with simple operations and that is waterproof and dustproof by reliably injecting resin.

[0007] Another object of the present invention is to provide a method for manufacturing a motor that allows a waterproof and dustproof motor to be manufactured with simple operations. [Means for solving the problem]

[0008] An exemplary motor of the present invention includes a shaft rotatable about a central axis extending vertically, a cylindrical bearing housing rotatably supporting the shaft via bearings, a cylindrical casing extending axially about the central axis and having a cylindrical portion located radially outside the bearing housing, and a cover portion extending radially inward from the upper end of the cylindrical portion and holding an upper end of the outer peripheral surface of the bearing housing, a stator fixed to at least one of the inner peripheral surface of the cylindrical portion of the casing and the outer peripheral surface of the bearing housing, a rotor fixed to the shaft and positioned radially outward from the casing, a cover portion covering an opening formed at the lower end of the cylindrical portion of the casing, and a resin portion covering the stator within a space surrounded by the bearing housing, the casing, and the cover portion. The cover portion includes an annular base and a bushing located radially inside the base and fixed to the lower end of the outer peripheral surface of the bearing housing.

[0009] An exemplary blower device of the present invention includes: a motor; an impeller attached to the rotor; and a frame that covers the impeller from the outside in the radial direction, wherein the base is formed integrally with the frame.

[0010] An exemplary method for manufacturing a motor according to the present invention includes a bearing housing mounting step of mounting a bearing housing to a lid portion of a casing, a stator mounting step of mounting a stator to at least one of an inner peripheral surface of the cylindrical portion of the casing and an outer peripheral surface of the bearing housing, a resin injection step of injecting resin between the casing and the bearing housing through an opening formed axially downward in the cylindrical portion of the casing to cover the stator with resin, and a covering step of covering the opening of the casing with a cover portion. The covering step is performed after the resin injection step. [Effects of the Invention]

[0011] The exemplary motor of the present invention can be manufactured with simple work and is waterproof and dustproof.

[0012] Furthermore, the exemplary blower device of the present invention can be manufactured with simple operations, and is waterproof and dustproof by reliably injecting resin.

[0013] Furthermore, according to the exemplary method for manufacturing a motor of the present invention, a waterproof and dustproof motor can be manufactured with simple operations. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing an example of a blower according to the present invention. [Figure 2] FIG. 2 is an exploded perspective view of the blower shown in FIG. [Figure 3] FIG. 3 is a perspective view of the second frame. [Figure 4] FIG. 4 is a vertical cross-sectional view of the blower shown in FIG. [Figure 5] FIG. 5 is a perspective view of the casing. [Figure 6] FIG. 6 is a plan view of the circuit board and the stator. [Figure 7] FIG. 7 is a bottom view of the circuit board. [Figure 8] FIG. 8 is a bottom view of the stator. [Figure 9] FIG. 9 is an exploded perspective view of the stator and the circuit board. [Figure 10] FIG. 10 is an enlarged cross-sectional view of the snap-fit ​​portion. [Figure 11] FIG. 11 is an enlarged cross-sectional view of the first recess and the first snap-fit ​​portion. [Figure 12] FIG. 12 is an enlarged cross-sectional view of the second recess and the second snap-fit ​​portion. [Figure 13] FIG. 13 is a flowchart showing the manufacturing process of the blower. [Figure 14] FIG. 14 is a cross-sectional view of the casing, which houses the stator and the circuit board, turned upside down. [Figure 15]FIG. 15 is a plan view showing a recess and a snap-fit ​​portion of a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. In this specification, the direction parallel to the central axis Cx of the fan A is referred to as the "axial direction," the direction perpendicular to the central axis Cx of the fan A is referred to as the "radial direction," and the direction along the arc centered on the central axis Cx of the fan A is referred to as the "circumferential direction." In this specification, the shape and positional relationship of each part of the fan A will be described with the axial direction as the up-down direction and the air intake port 121 side of the frame 10 relative to the impeller 30 as the upper side. The up-down direction is a term used merely for explanation and does not limit the positional relationship or direction when the fan A is in use. Furthermore, "upstream" and "downstream" refer to the upstream and downstream directions, respectively, of the flow direction of the airflow generated when the impeller 30 is rotated.

[0016] <1. Configuration of the air blower A> Fig. 1 is a perspective view showing an example of a blower A according to the present invention. Fig. 2 is an exploded perspective view of the blower A shown in Fig. 1. Fig. 3 is a perspective view of a second frame 102. Fig. 4 is a vertical cross-sectional view of the blower A shown in Fig. 1.

[0017] As shown in Figures 1 to 4, the blower A according to this embodiment includes a frame 10, a motor 20, and an impeller 30. The motor 20 is fixed to the frame 10. A rotor 25 (described later) of the motor 20 is rotatable relative to the frame 10. The impeller 30 is attached to the rotor 25, and rotates around the central axis Cx as the rotor 25 rotates.

[0018] That is, the blower A has a motor 20, an impeller 30 attached to a rotor 25 (described later) of the motor 20, and a frame 10 covering the impeller 30 from the radially outward side.

[0019] In the blower device A, when the impeller 30 rotates in a predetermined rotation direction Rd (see Figure 1), air is pushed by the blades 32 of the impeller 30, which will be described later, and an airflow is generated inside the air tunnel portion 12 of the frame 10, which will be described later.

[0020] <2. Frame 10 Configuration> As shown in FIGS. 1 to 4, the frame 10 has a frame main body 11 and an air duct portion 12. In this embodiment, the frame 10 is formed as an integrally molded body with a base 261 of a cover portion 26 (described later) of the motor 20. That is, the base 261 is a part of the motor 20 and also a part of the frame 10. Details of the base 261 will be described later. That is, the base 261 is formed integrally with the frame 10.

[0021] The frame body 11 is an exterior member of the blower A. The frame body 11 is made of resin. The air duct 12 is disposed inside the frame body 11 and has a cylindrical inner peripheral surface. As shown in Figures 1 and 4, the air duct 12 extends along the central axis Cx. The center line of the inner peripheral surface of the air duct 12 coincides with the central axis Cx.

[0022] The air tunnel 12 is a guide that guides the airflow generated by the rotation of the impeller 30 along the central axis Cx. The upper axial end of the air tunnel 12 is an intake port 121, and the lower axial end is an exhaust port 122. That is, as the impeller 30 rotates, air is sucked in through the intake port 121, and the airflow accelerated by the impeller 30 is discharged from the exhaust port 122.

[0023] The frame main body 11 has a square rectangular parallelepiped shape when viewed from the axial direction. When viewed from the axial direction, mounting holes 111 are formed at the four corners of the square shape, penetrating in the axial direction. For example, mounting screws, bosses, etc. provided on the equipment are inserted into the mounting holes 111. The frame main body 11 is then fixed to the equipment by using a fixing method such as fastening a nut to the protruding portion of the screw or caulking the boss. Although the frame main body 11 has a square shape when viewed from the axial direction, it may also be a circle or a polygon such as a rectangle or hexagon. A shape matching the shape of the position where the fan device A is to be installed on the equipment to which the fan device A is to be installed may be adopted.

[0024] The frame 10 has a plurality of stator vanes 13 that protrude radially inward from the inner circumferential surface of the air tunnel 12. The stator vanes 13 connect the air tunnel 12 to a base 261 of the motor 20. In other words, the base 261 is held in the air tunnel 12 via the stator vanes 13. The airflow generated by the rotation of the impeller 30 is rectified by the stator vanes 13.

[0025] As shown in Figures 1 and 2, the frame 10 is separable into a first frame portion 101 and a second frame portion 102. The first frame portion 101 is disposed above the second frame portion 102. That is, the frame 10 has the first frame portion 101 and the second frame portion 102 connected axially below the first frame portion 101. The first frame portion 101 and the second frame portion 102 can be separably combined using a snap-fit ​​mechanism, but this is not limiting. For example, they may be fixed using fasteners such as screws.

[0026] The frame 10 has a lead wire arrangement portion 103 formed by combining a first frame portion 101 and a second frame portion 102. Lead wires 45 (described later) connected to a circuit board 40 (described later) of the motor are arranged in the lead wire arrangement portion 103.

[0027] The air blower A configured in this way can stably discharge a constant amount of air.

[0028] 3. Configuration of the motor 20 The motor 20 is disposed inside the frame 10. The motor 20 has a shaft 21, a bearing housing 22, a casing 23, a stator 24, a rotor 25, a cover portion 26, a resin portion 60, a circuit board 40, and a wiring portion 29.

[0029] <3.1 Shaft 21> The shaft 21 extends along the central axis Cx. The shaft 21 is cylindrical, and its center line coincides with the central axis Cx. The shaft 21 is rotatably supported by the bearing housing 22 by bearings 211 at two axially spaced locations. In other words, the shaft 21 is rotatable around the central axis Cx that extends vertically.

[0030] The bearing 211 is a ball bearing here, but is not limited to this. A wide variety of bearings can be used that can support the shaft 21 rotatably around the central axis Cx. The shaft 21 is inserted into and fixed to the inner cylinder of the bearing 211. Here, the shaft 21 is fixed to the inner cylinder of the bearing 211 by press-fitting, but is not limited to this. The shaft 21 and the inner cylinder of the bearing 211 may also be fixed by adhesive, screwing, or other fixing methods.

[0031] The shaft 21 is rotatably supported by bearings 211 at two axially separated locations. This makes it possible to suppress axial wobble and deviation during rotation of the shaft 21. This stabilizes the rotation of the shaft 21.

[0032] <3.2 Bearing housing 22> The bearing housing 22 is made of metal and has a cylindrical shape extending along the central axis Cx. The bearing housing 22 has an inner circumferential surface provided with a bearing holder 221 for holding the bearing 211. The bearing holder 221 has a stepped shape that expands from the inner circumferential surface in a direction perpendicular to the central axis Cx. The bearing 211 can be positioned in the axial direction by bringing the outer ring of the bearing 211 into contact with the bearing holder 221. The bearing 211 is fixed to the inner circumferential surface of the bearing housing 22 by press-fitting. However, the bearing 211 may be fixed by a fixing method other than press-fitting, such as screwing or adhesive bonding. The bearing housing 22 is cylindrical and rotatably supports the shaft 21 via the bearing 211.

[0033] The stator 24 is fixed to the outer peripheral surface of the bearing housing 22. More specifically, a stator core 241 (described later) of the stator 24 is fixed to the outer peripheral surface of the bearing housing 22. The stator core 241 is fixed to the outer peripheral surface of the bearing housing 22 by press-fitting. However, a fixing method other than press-fitting may be used to fix the stator 24 to the bearing housing 22.

[0034] A cover portion 26 is attached to the lower end of the outer circumferential surface of the bearing housing 22. The cover portion 26 will be described in detail later.

[0035] <3.3 Casing 23> The casing 23 will be described below with reference to new drawings. Fig. 5 is a perspective view of the casing 23. As shown in Figs. 4, 5, etc., the casing 23 is a cylindrical shape with a bottom that extends axially around the central axis Cx, and holds the bearing housing 22.

[0036] The casing 23 has a tubular portion 231 and a lid portion 232. As shown in Fig. 4, the tubular portion 231 has a cylindrical shape extending along the central axis Cx. The center line of the tubular portion 231 overlaps with the central axis Cx. The tubular portion 231 of the casing 23 has an opening 230 at its lower end. The opening 230 is covered by the cover portion 26.

[0037] The lid portion 232 extends radially inward from the upper end of the axial direction of the cylindrical portion 231. The lid portion 232 has a bearing housing mounting boss 233. The bearing housing mounting boss 233 extends axially downward from the center of the lid portion 232. The bearing housing mounting boss 233 is cylindrical. The upper end of the outer circumferential surface of the bearing housing 22 is fixed to the inner circumferential surface of the bearing housing mounting boss 233. The bearing housing 22 and the bearing housing mounting boss 233 are fixed by press-fitting, but the invention is not limited to this and other fixing methods such as adhesive bonding and welding may also be used.

[0038] Furthermore, the cylindrical portion 231 of the casing 23 has a first protrusion 291 (described later) of the wiring portion 29. The first protrusion 291 is formed integrally with the cylindrical portion 231. Details of the wiring portion 29 and the first protrusion 291 will be described later.

[0039] <3.4 Cover part 26> The cover portion 26 extends in a direction perpendicular to the central axis Cx. The cover portion 26 has a base 261 and a bushing 262. As shown in FIGS. 2 and 4, the base 261 is annular. The outer edge of the base 261 connects to the radially inner end of the stator blade 13 of the frame 10. In the motor 20 of this embodiment, the base 261 of the cover portion 26 and the second frame portion 102 of the frame 10 are an integrally molded resin body. That is, the second frame portion 102 and the base 261 are integrally formed.

[0040] The bushing 262 has an annular shape and is disposed in the center of the base 261. The bushing 262 is formed integrally with the base 261. That is, at least a portion of the bushing 262 may be fixed integrally to the base 261. This configuration makes it easier to manufacture the cover portion 26.

[0041] In this embodiment, the bushing 262 is made of metal, and the base 261 is made of resin. Therefore, the cover portion 26 is, for example, an insert-molded body. However, this is not limited thereto, and the bushing 262 may be fixed (integrated) to the base 261 by a fixing method such as adhesive bonding or screw fastening. Also, in this embodiment, the bushing 262 is formed of a material harder than the bearing housing 22. However, this is not limited thereto. The lower end of the bearing housing 22 is press-fitted into the bushing 262. In other words, the cover portion 26 has an annular base 261 and the bushing 262 that is disposed radially inside the base 261 and fixed to the lower end of the outer circumferential surface of the bearing housing 22.

[0042] As shown in FIG. 4 and other figures, the cover part 26 has a cap part 263 that closes the opening at the lower end of the bearing housing 22. The cap part 263 is attached to the lower surface of the base 261 of the cover part 26. The cap part 263 also fits tightly against the inner circumferential surface of the bearing housing 22. Here, "fitting tightly" means that there are no gaps through which foreign matter such as water, dirt, and dust can pass. In other words, the cover part 26 covers the opening 230 formed at the lower end of the casing 23. In this way, the cap part 263 fits tightly against the opening at the lower end inside the bearing housing 22, thereby preventing foreign matter such as water, dirt, and dust from entering the bearing housing 22. This allows the bearing 211 to operate stably for a long period of time.

[0043] The cover portion 26 has a second protrusion 292. The second protrusion 292 protrudes radially outward from the radial outer edge of the base 261. When the cover portion 26 is attached to the casing 23, the second protrusion 292 is disposed axially below the first protrusion 291. Details of the second protrusion 292 will be described later.

[0044] <3.5 Stator 24> 4 and other figures, the stator 24 is housed inside a space surrounded by the bearing housing 22, the casing 23, and the cover portion 26. The stator 24 includes a stator core 241, an insulator 242, and a coil 243.

[0045] The stator core 241 is electrically conductive. The stator core 241 is centered on a central axis Cx that extends vertically. In this embodiment, the stator core 241 has a structure in which electromagnetic steel plates are laminated. However, the stator core 241 is not limited to this configuration and may be a single member formed by sintering powder, casting, or the like. The stator core 241 has an annular core back portion 244 and a plurality of teeth portions 245. The core back portion 244 is annular and extends in the axial direction. The teeth portions 245 protrude radially outward from the outer peripheral surface of the core back portion 244. The plurality of teeth portions 245 are arranged at equal intervals in the circumferential direction.

[0046] The insulator 242 is a molded resin body. The insulator 242 covers at least the tooth portion 245 of the stator core 241. That is, the insulator 242 covers at least a part of the stator core 241. The coil 243 is formed on the tooth portion 245 covered by the insulator 242. That is, the coil 243 is formed by winding a conductor around the insulator 242. The motor 20 is a DC brushless motor. Therefore, three conductors 247 are drawn out from different coils 243. That is, the stator 24 has the coil 243 and the conductors 247 drawn out from the coil 243.

[0047] The insulator 242 insulates the stator core 241 from the coil 243. In this embodiment, the insulator 242 is a molded resin body, but is not limited to this. A wide variety of configurations that can insulate the stator core 241 from the coil 243 can be adopted.

[0048] The insulator 242 has an insulator tubular portion 246 that extends axially downward. The lower end of the insulator tubular portion 246 contacts the upper surface of the circuit board 40.

[0049] In this embodiment, the inner peripheral surface of the stator core 241 is fixed to the outer peripheral surface of the bearing housing 22 by press-fitting. In this way, the stator 24 is fixed to the bearing housing 22. Note that the method of fixing the stator 24 to the bearing housing 22 is not limited to press-fitting, and fixing methods such as welding and adhesive may also be used. Also, in this embodiment, the stator 24 is fixed to the bearing housing 22, but this is not limited thereto, and the outer peripheral surface of the stator 24 may be fixed to the inner peripheral surface of the cylindrical portion 231 of the casing 23. Furthermore, the stator 24 may be fixed to both the bearing housing 22 and the casing 23. In other words, the stator 24 is disposed inside the casing 23 and fixed to at least one of the casing 23 and the bearing housing 22.

[0050] <3.6 Rotor 25> The rotor 25 is disposed radially outward of the stator 24. The rotor 25 is fixed to the shaft 21. That is, the rotor 25 is fixed to the shaft 21 and disposed radially outward of the casing 23. The rotor 25 has a rotor cover 251 and a magnet 252. The rotor cover 251 is cylindrical with a lid.

[0051] The rotor cover 251 has a rotor cylindrical portion 253, a rotor top plate portion 254, and a shaft fixing boss 255. The rotor cylindrical portion 253 has an annular shape extending in the axial direction. The rotor cylindrical portion 253 is disposed radially outward of the casing 23.

[0052] The rotor top plate portion 254 extends radially inward from the axial upper end of the rotor cylindrical portion 253. The shaft fixing boss 255 is located in the center of the rotor top plate portion 254 when viewed from the axial direction. The shaft fixing boss 255 and the rotor top plate portion 254 are molded as a single unit. The shaft fixing boss 255 has a cylindrical shape that penetrates in the axial direction. The shaft 21 penetrates the shaft fixing boss 255, and the outer peripheral surface of the shaft 21 is fixed to the inner peripheral surface of the shaft fixing boss 255. In this way, the rotor cover 251 of the rotor 25 is fixed to the shaft 21.

[0053] 2, 4, etc., magnet 252 is cylindrical. Magnet 252 is cylindrical and magnetized with N poles and S poles alternately arranged in the circumferential direction. The outer circumferential surface of magnet 252 is fixed to the inner circumferential surface of rotor cylindrical portion 253.

[0054] In this embodiment, the magnet 252 is an integrally molded body made of resin mixed with magnetic powder. However, the present invention is not limited to this configuration, and the magnet 252 may be formed by arranging multiple magnets in the circumferential direction and fixing them with resin or the like.

[0055] As described above, in the motor 20 of this embodiment, the rotor 25 is disposed radially outward from the stator 24. The rotor 25 rotates around the stator 24. In other words, the motor 20 is an outer rotor type motor.

[0056] Furthermore, the impeller 30 is attached to the outside of the rotor cover 251. The impeller 30 is fixed to the rotor cover 251 by, for example, adhesive. As a result, the impeller 30 rotates when the rotor 25 rotates. Note that the method of fixing the impeller 30 to the rotor cover 251 is not limited to adhesive, and they may be fixed by other fixing methods such as press fitting, welding, or melt-adhesion.

[0057] 3.7 Configuration of the circuit board 40 Fig. 6 is a plan view of the circuit board 40 and the stator 24. Fig. 7 is a bottom view of the circuit board 40. In the circuit board 40 shown in Fig. 7, the conductors 247 are indicated by dashed lines. The circuit board 40 is annular. Electronic components 41 are attached to the surface of the circuit board 40, and a control circuit that supplies power to the coil 243 is formed thereon.

[0058] A through-hole 400 is formed in the center of the circuit board 40, penetrating in the axial direction. The bearing housing 22 passes through the through-hole 400. As shown in FIG. 4 and other figures, the circuit board 40 is disposed below the stator 24 and is held by the insulator 242 of the stator 24. That is, the circuit board 40 is disposed on one axial side of the stator core 241. In this case, the circuit board 40 is disposed inside the casing 23. That is, the motor 20 further includes a circuit board 40 disposed inside the casing 23.

[0059] The circuit board 40 has recesses 42 recessed radially outward from the peripheral edge of the through hole 400. That is, the circuit board 40 has the through hole 400 formed in the center when viewed from the axial direction, and a plurality of recesses 42 recessed radially outward from the peripheral edge of the through hole 400.

[0060] A snap fit portion 50 provided on the insulator 242 is fitted into the recess 42. By fitting the snap fit portion 50 into the recess 42, the circuit board 40 is held in the stator 24. Details of the recess 42 and the snap fit portion 50 will be described later.

[0061] The outer peripheral surface of the circuit board 40 has cutouts 43 recessed radially inward. Different conductors 247 are disposed in the cutouts 43, and the ends of the conductors 247 are wired to the underside of the circuit board 40. The ends of the conductors 247 are electrically connected to lands 44 disposed on the bottom surface of the circuit board 40 (see FIG. 7 ). That is, the circuit board 40 is electrically connected to the coil 243. The conductors 247 are also wired from the top surface to the bottom surface of the circuit board 40 through the cutouts 43, and are electrically connected to the circuit (lands 44) on the bottom surface of the circuit board 40. The electrical connection between the conductors 247 and the lands 44 is achieved by, for example, soldering. However, the connection between the conductors 247 and the lands 44 is not limited to soldering, and may be achieved by bonding with a conductive adhesive, screwing, or the like.

[0062] By providing the notch 43 in the circuit board 40, the conductor 247 can be configured to be routed to the underside of the circuit board 40 via the notch 43. This makes it easier to route the conductor 247 to the underside of the circuit board 40 compared to when the circuit board 40 is provided with a hole for passing the conductor 247 instead of the notch 43. For example, after the circuit board 40 is attached below the stator 24, the conductor 247 is routed around to the underside of the circuit board 40. At this time, the conductor 247 is routed through the notch 43, which is an opening on the radial outer edge of the circuit board 40, and the stator 24 is less likely to get in the way, making it easier to route the conductor 247.

[0063] The stator 24 has lead-out points 248 from which the conductor wires are led out from the coils 243. Three lead-out points 248 are provided on the stator 24. A different conductor wire 247 is led out from each of the lead-out points 248.

[0064] 6, when the circuit board 40 is attached to the stator 24, the notch 43 and the lead-out portion 248 are misaligned in the circumferential direction. With this configuration, the conductor 247 can be routed along the tangential direction of the core back portion 244 of the stator core 241. This reduces interference between the conductor 247 and components such as the casing 23, and prevents the conductor 247 from breaking.

[0065] Lead wires 45 are connected to circuit board 40 (see FIG. 4). That is, motor 20 further has lead wires 45 connected to the circuit board. Lead wires 45 connect circuit board 40 to a power supply device arranged outside motor 20, in other words, outside blower A.

[0066] <3.8 Recess 42 and snap-fit ​​portion 50> FIG. 8 is a bottom view of the stator 24. FIG. 9 is a perspective view of the stator 24 and the circuit board 40 in an exploded state. FIG. 10 is an enlarged cross-sectional view of the snap-fit ​​portion 50. As shown in FIGS. 8 and 9, the insulator 242 has two snap-fit ​​portions 50. The circuit board 40 has two recesses 42. The snap-fit ​​portions 50 fit into the recesses 42 formed in the through-holes 400 of the circuit board 40. That is, the insulator 242 has the snap-fit ​​portion 50 that extends toward the circuit board 40 in the axial direction and fits into the recesses 42 of the circuit board 40. Furthermore, the insulator 242 has the two snap-fit ​​portions 50, and the circuit board 40 has the two recesses 42.

[0067] The circuit board 40 has two recesses 42 with different shapes. That is, the circuit board 40 has at least one recess 42 whose shape, when viewed in the axial direction, is different from the other recesses 42.

[0068] In the following description, with regard to the two recesses 42, one recess 42 will be referred to as the first recess 42a (see Figures 7, 9, etc.) and the other recess 42 will be referred to as the second recess 42b (see Figures 7, 9, etc.) as necessary. In addition, with regard to the two snap-fit ​​portions 50, the first snap-fit ​​portion 50a that fits into the first recess 42a and the second snap-fit ​​portion 50b that fits into the second recess 42b as necessary.

[0069] 11 is an enlarged cross-sectional view of the first recess 42a and the first snap-fit ​​portion 50a. In FIG. 11, a line passing through the center (central axis Cx) of the through-hole 400 and extending in the radial direction is taken as a reference line Sd.

[0070] 11, the first recess 42a has an inward surface 421 and a first inner side surface 422 and a second inner side surface 423 that face each other in the circumferential direction. That is, the recess 42a (42b) has a pair of inner sides (the first inner side surface 422 and the second inner side surface 423, and the third inner side surface 425 and the fourth inner side surface 426) that face each other in the circumferential direction. The inward surface 421 faces radially toward the center of the through hole 400. The first inner side surface 422 and the second inner side surface 423 are connected to both ends of the inward surface 421 in the circumferential direction. The first inner side surface 422 and the second inner side surface 423 face each other in the circumferential direction.

[0071] In the first recess 42a, the circumferential distance between the first inner surface 422 and the second inner surface 423 narrows as the recess 42a extends radially outward. That is, the circumferential distance between the first inner surface 422 and the second inner surface 423 narrows as the recess 42a extends radially outward. The first inner surface 422 and the second inner surface 423 approach each other as the recess 42a extends radially outward. More specifically, when viewed from the axial direction, the first inner surface 422 and the second inner surface 423 are inclined with respect to the reference line Sd and are line-symmetrical with respect to the reference line Sd. That is, the first inner surface 422 and the second inner surface 423 of at least one recess 42a are arranged line-symmetrically with respect to the reference line Sd. Note that the first inner surface 422 and the second inner surface 423 do not have to be line-symmetrical.

[0072] Note that, in the first recess 42a, the circumferential width between the first inner surface 422 and the second inner surface 423 narrows radially outward, but is not limited to this. As will be described in detail later, for example, the circumferential width between the first inner surface 422 and the second inner surface 423 may be narrowed radially inward (see FIG. 15).

[0073] Fig. 12 is an enlarged cross-sectional view of the second recess 42b and the second snap-fit ​​portion 50b. In Fig. 12, similar to Fig. 11, a line passing through the center (central axis Cx) of the through-hole 400 and extending in the radial direction is taken as a reference line Sd.

[0074] 12, the second recess 42b has an inward surface 424 and a third inner surface 425 and a fourth inner surface 426 that face each other in the circumferential direction. The inward surface 424 faces radially toward the center of the through hole 400. The third inner surface 425 and the fourth inner surface 426 are connected to both ends of the inward surface 424 in the circumferential direction. The third inner surface 425 and the fourth inner surface 426 face each other in the circumferential direction.

[0075] In the second recess 42b, the circumferential distance between the third inner surface 425 and the fourth inner surface 426 narrows as the recess 42b extends radially outward. That is, the circumferential distance between the third inner surface 425 and the fourth inner surface 426 narrows as the recess 42b extends radially toward one side. The third inner surface 425 extends parallel to the reference line Sd. That is, one inner surface 425 of at least one recess 42b extends parallel to the reference line Sb that passes through the center of the through hole (the central axis Cx) and extends radially. Note that "parallel" here includes not only cases where the two surfaces are completely parallel, but also cases where the two surfaces are inclined by several degrees to several tens of degrees. The inner surface 426 approaches the inner surface 425 as the recess 42b extends radially outward.

[0076] 9, 11, etc., the first snap-fit ​​portion 50a has an elastic support portion 51 and a claw portion 52. The elastic support portion 51 extends downward along the central axis Cx from the lower end portion of the insulator tubular portion 246. The elastic support portion 51 is elastically bendable and deformable.

[0077] The elastic support portion 51 has a first outer surface 511 and a second outer surface 512 disposed at both circumferential ends. That is, the snap-fit ​​portion 50a has outer surfaces (the first outer surface 511 and the second outer surface 512) disposed at both circumferential ends. The first outer surface 511 and the second outer surface 512 are surfaces facing opposite sides in the circumferential direction. The circumferential width of the first outer surface 511 and the second outer surface 512 narrows as they extend radially outward. The first outer surface 511 and the second outer surface 512 approach each other as they extend radially outward. The first outer surface 511 and the second outer surface 512 are symmetrical with respect to a line passing through the circumferential center of the elastic support portion 51 (reference line Sd in FIG. 11 ).

[0078] The claw portion 52 protrudes radially outward from the lower end of the elastic support portion 51. The claw portion 52 has an inclined surface 521 and a contact surface 522. The inclined surface 521 is a surface that has an inclination that slopes radially outward as it extends upward. The contact surface 522 is perpendicular to the central axis Cx and contacts the upper end of the inclined surface 521.

[0079] As shown in FIGS. 10 and 11, the first snap-fit ​​portion 50a fits into the first recess 42a. The first snap-fit ​​portion 50a is inserted into the first recess 42a from above. At this time, the inclined surface 521 comes into contact with the inward surface 421 of the first recess 42a. When the first snap-fit ​​portion 50a is further moved downward, the inclined surface 521 is pressed against the inward surface 421, causing the elastic support portion 51 to elastically deform radially inward. As a result, the claw portion 52 of the first snap-fit ​​portion 50a passes through the first recess 42a.

[0080] When the claw portion 52 moves below the lower surface of the circuit board 40, the elastic support portion 51 returns to its original shape. At this time, the contact surface 522 of the claw portion 52 comes into contact with the lower surface of the circuit board 40. At this time, the lower surface of the insulator tubular portion 246 comes into contact with the upper surface of the circuit board 40.

[0081] When the claw portion 52 passes through the first recess 42a, the first outer surface 511 of the elastic support portion 51 comes into contact with the first inner surface 422 of the first recess 42a, and the second outer surface 512 comes into contact with the second inner surface 423. The first snap-fit ​​portion 50a is radially separated from the inward surface 421 of the first recess 42a (see FIG. 11). That is, at least one of the outer surfaces (the first outer surface 511 and the second outer surface 512) comes into contact with at least one of the inner surfaces (the first inner surface 411 and the second inner surface 412) of the recess 42a.

[0082] When viewed from the axial direction, the snap-fit ​​portion 50 may be configured to come into point contact with at least one of the first inner surface 411 and the second inner surface 412. Even in such a configuration, the snap-fit ​​portion 50 is positioned before coming into contact with the inward surface 421. This allows the circuit board 40 to be positioned even if variations occur in the shapes of the recess 42a and the snap-fit ​​portion 50.

[0083] 9, 12, etc., the second snap-fit ​​portion 50b has an elastic support portion 53 and a claw portion 54. The elastic support portion 53 extends downward along the central axis Cx from the lower end portion of the insulator tubular portion 246. The elastic support portion 53 is elastically bendable and deformable.

[0084] The elastic support portion 53 has a third outer surface 531 and a fourth outer surface 532 disposed at both circumferential ends. That is, the snap-fit ​​portion 50b has outer surfaces (the third outer surface 531 and the fourth outer surface 532) disposed at both circumferential ends. The third outer surface 531 and the fourth outer surface 532 are surfaces facing opposite sides in the circumferential direction. The circumferential width of the third outer surface 531 and the fourth outer surface 532 narrows as it extends radially outward. The third outer surface 531 extends along a line (reference line Sd in FIG. 12 ) passing through the circumferential center of the elastic support portion 53. The fourth outer surface 532 approaches the third outer surface 531 as it extends radially outward.

[0085] The claw portion 54 has the same configuration as the claw portion 52. The inclined surface 541 and the contact surface 542 of the claw portion 54 correspond to the inclined surface 521 and the contact surface 522 of the claw portion 52. Therefore, details of the claw portion 54 will be omitted.

[0086] As shown in Figures 10 and 12, the second snap-fit ​​portion 50b fits into the second recess 42b. The second snap-fit ​​portion 50b is inserted into the second recess 42b from above. At this time, the inclined surface 541 comes into contact with the inward surface 424 of the second recess 42b. When the second snap-fit ​​portion 50b is further moved downward, the inclined surface 541 is pressed against the inward surface 424, causing the elastic support portion 53 to elastically deform radially inward. As a result, the claw portion 54 of the second snap-fit ​​portion 50b passes through the second recess 42b.

[0087] When the claw portion 54 moves below the lower surface of the circuit board 40, the elastic support portion 53 returns to its original shape. At this time, the contact surface 542 of the claw portion 54 comes into contact with the lower surface of the circuit board 40. At this time, the lower surface of the insulator tubular portion 246 comes into contact with the upper surface of the circuit board 40.

[0088] When the claw portion 54 passes through the second recess 42b, the third outer surface 531 of the elastic support portion 53 comes into contact with the third inner surface 425 of the second recess 42b, and the fourth outer surface 532 comes into contact with the fourth inner surface 426. That is, at least one of the outer surfaces (the third outer surface 531 and the fourth outer surface 532) comes into contact with at least one of the inner surfaces (the third inner surface 431 and the fourth inner surface 432) of the recess 42b. This positions the second snap-fit ​​portion 50b and the second recess 42b in the circumferential direction. The second snap-fit ​​portion 50b is radially separated from the inward surface 424 of the second recess 42b.

[0089] In this way, the circuit board 40 is attached to the stator 24 by fitting the two snap-fit ​​portions 50 into the corresponding recesses 42. More specifically, the lower surface of the insulator tubular portion 246 comes into contact with the upper surface of the circuit board 40. The contact surfaces 522 of the claw portions 52 of the first snap-fit ​​portion 50a and the contact surfaces 542 of the claw portions 54 of the second snap-fit ​​portion 50b come into contact with the lower surface of the circuit board 40. As a result, the circuit board 40 is held by the insulator tubular portion 246 and the snap-fit ​​portions 50.

[0090] The first outer surface 511 and the second outer surface 512 of the elastic support portion 51 of the first snap-fit ​​portion 50a come into contact with the first inner surface 422 and the second inner surface 423 of the first recess 42a. This allows the first recess 42a to be held in the circumferential direction by the first snap-fit ​​portion 50a. The circuit board 40 is held in place by the contact between the first outer surface 511 and the second outer surface 512, which are inclined in the radial direction, and the first inner surface 422 and the second inner surface 423, which are also inclined in the radial direction. Therefore, even if there is variation in the radial thickness of the first snap-fit ​​portion 50a, the radial length of the first recess 42a, or the circumferential positions of the first inner surface 422 and the second inner surface 423, the circuit board 40 can be accurately positioned in the circumferential direction. Furthermore, because the first inner surface 422 and the second inner surface 423 of the recess 42a and the first outer surface 511 and the second outer surface 512 of the snap-fit ​​portion 50a are configured to be line-symmetrical, the circuit board 40 can be held with the same strength in the circumferential direction, and when the snap-fit ​​portion 50a is fixed, the contact force between the first inner surface 422 and the second inner surface 423 and the first outer surface 511 and the second outer surface 512 becomes approximately uniform. This allows for improved positioning accuracy of the circuit board 40 in the circumferential direction.

[0091] Additionally, the third outer surface 531 and the fourth outer surface 532 of the elastic support portion 53 of the second snap-fit ​​portion 50b contact the third inner surface 425 and the fourth inner surface 426 of the second recess 42b. This allows the second recess 42b to be held in the circumferential direction relative to the second snap-fit ​​portion 50b. The circuit board 40 is held by contact between the radially inclined fourth outer surface 532 and the radially inclined fourth inner surface 426. Therefore, even if there is variation in the radial thickness of the second snap-fit ​​portion 50b, the radial length of the second recess 42b, or the circumferential positions of the third inner surface 425 and the fourth inner surface 426, the circuit board 40 can be accurately positioned. Furthermore, because the third outer surface 531 contacts the third inner surface 425 of the second recess 42b, circumferential movement of the circuit board 40 can be effectively restricted.

[0092] The circuit board 40 is held in the circumferential direction at two different points in the circumferential direction, so that circumferential movement is restricted. With this configuration, the circuit board 40 can be positioned in the circumferential direction relative to the insulator 242 by the snap-fit ​​portion 50. Therefore, positioning members and recesses can be omitted.

[0093] With the above configuration, the first outer surface 511 and the second outer surface 512 of the first snap-fit ​​portion 50a contact the first inner surface 422 and the second inner surface 423 of the first recess 42a in the circumferential direction, and the third outer surface 531 and the fourth outer surface 532 of the second snap-fit ​​portion 50b contact the fourth inner surface 426 of the second recess 42b in the circumferential direction. Therefore, the two snap-fit ​​portions 50a, 50b and the two recesses 42a, 42b can accurately position the circuit board 40 in the circumferential direction. This allows the number of snap-fit ​​portions 50 and recesses 42 to be reduced. Reducing the recesses reduces the area where the recesses are formed on the circuit board 40, expanding the area where the wiring pattern is formed and increasing the degree of freedom in the wiring pattern.

[0094] Furthermore, since the two recesses 42 and the two snap-fit ​​portions 50 have different shapes, the circuit board 40 can be attached to the stator 24 in the correct orientation and position.

[0095] Furthermore, by making one of the inner surfaces (third inner surface 425) of the second recess 42b parallel to the reference line Sb, the accuracy of circumferential positioning between the inner surface (third inner surface 425) of the recess 42b and the outer surface (third outer surface 531) of the snap fit portion 50b can be improved.

[0096] The circumferential distance between the pair of inner surfaces of at least one recess 42 narrows in the circumferential direction as it moves radially outward. With this configuration, the pair of inner surfaces of the recess 42 come into contact with the outer surface of the snap-fit ​​portion 50, and the snap-fit ​​portion 50 is disposed inside the recess 42. This makes it easier for the snap-fit ​​portion 50 to enter the recess from the radially inner side, improving workability.

[0097] <3.9 Configuration of wiring section 29> When viewed in the axial direction, the wiring portion 29 protrudes radially outward from the radial outer edge of the casing 23. The wiring portion 29 has a wiring space 290 in which the lead wires 45 are arranged. In other words, the motor 20 further has the wiring portion 29 having the wiring space 290 in which the lead wires 45 are arranged.

[0098] The wiring portion 29 has a first protrusion 291 and a second protrusion 292. As described above, the first protrusion 291 is formed integrally with the casing 23, and the second protrusion 292 is formed integrally with the cover portion 26. When the first protrusion 291 and the second protrusion 292 are stacked one on top of the other, a wiring space 290 extending in the radial direction is formed inside the wiring portion 29.

[0099] The wiring portion 29 has a first protrusion 291 extending radially outward from the lower end of the casing 23 and a second protrusion 292 extending radially outward from the outer circumferential surface of the base 261.

[0100] More specifically, the first protrusion 291 has a wiring portion top plate portion 2911 and a pair of wiring portion side walls 2912. The wiring portion top plate portion 2911 is plate-shaped and extends in a direction intersecting the central axis Cx. When viewed in the axial direction, the wiring portion top plate portion 2911 has a rectangular shape extending in the axial direction. The pair of wiring portion side walls 2912 extend axially downward from both circumferential ends of the wiring portion top plate portion 2911. The wiring portion top plate portion 2911 and the pair of wiring portion side walls 2912 are integrally molded. The axial lower surface of the first protrusion 291 is recessed axially upward and radially.

[0101] The second protrusion 292 is a plate-like member extending in a direction intersecting the central axis Cx. The second protrusion 292 is rectangular and is disposed opposite the wiring portion top plate portion 2911 of the first protrusion 291 in the axial direction.

[0102] The wiring portion 29 is disposed in contact with the axial lower ends of the pair of wiring portion sidewall portions 2912 of the first protrusion 291. That is, the second protrusion 292 covers the recess on the lower surface of the first protrusion 291. As a result, a wiring space 290 extending in the radial direction is formed in the wiring portion 29. The wiring portion top plate portion 2911 and the second protrusion 292 are in close contact with each other. This prevents foreign matter such as water, dust, and dirt from entering the wiring space 290 of the wiring portion 29. It also prevents airflow generated by the impeller 30 from entering. The wiring portion 29 formed in the casing 23 and the base 261 holds the lead wire 45. That is, the lead wire 45 is securely held by the casing 23 and the base 261. Because the lead wire 45 is securely held, even if a force pulling the lead wire 45 is applied, the force acting on the lead wire 45 is applied to the wiring portion 29. This reduces the force acting on the connection between the lead wire 45 and the circuit board 40. This makes it possible to prevent the lead wire 45 from coming off the circuit board 40.

[0103] A lead wire placement section 103 in which the lead wire 45 is placed is formed in the axial gap between the first frame section 101 and the second frame section 102, and the lead wire placement section 103 is connected to the wiring section 29. With this configuration, the lead wire 45 can be stably held.

[0104] The first protruding portion 291 may be in contact with at least the first frame portion 101. With this configuration, wind leakage to the lead wire placement portion 103 can be suppressed.

[0105] 3.10 Configuration of the resin part 60 The stator 24 and circuit board 40 are disposed in the space surrounded by the casing 23, bearing housing 22, and cover portion 26. After the stator 24 and circuit board 40 are positioned accurately, molten resin is poured into the casing 23. The resin is then cured to form the resin portion 60. That is, the resin portion 60 covers the stator 24 within the space surrounded by the bearing housing 22, casing 23, and cover portion 26.

[0106] That is, in the motor 20 of this embodiment, the stator 24 and the circuit board 40 housed in the casing 23 are sealed by the resin part 60. The motor 20 has the configuration described above.

[0107] In the motor 20, the upper end of the bearing housing 22 is held by the casing 23, and the lower end is held by the cover portion 26. Therefore, when the motor 20 is driven, the forces acting on the upper axial end and lower axial end of the bearing housing 22 are balanced, suppressing vibration of the motor 20. Furthermore, when the bearing housing 22 and the cover portion 26 are connected, a bushing 262 is provided between the base 261 and the bearing housing 22. This makes it possible to suppress deformation of the bearing housing 22 and the base 261 due to the force acting when the bearing housing 22 and the cover portion 26 are connected.

[0108] <4. Impeller 30 Configuration> The impeller 30 includes an impeller hub 31 and a plurality of blades 32. The impeller 30 may be, for example, an injection-molded resin body, but is not limited to this. The impeller 30 is not limited to resin and may be made of metal. Furthermore, the blades 32 may be formed separately from the impeller hub 31 and fixed by a fixing method such as adhesive or welding.

[0109] 1, 2, etc., the impeller hub 31 includes a cover portion 311 and an impeller cylindrical portion 312. The cover portion 311 has a disk shape that expands in the radial direction. The impeller cylindrical portion 312 has a cylindrical shape that extends axially downward from the radial outer edge of the cover portion 311.

[0110] The rotor 25 is fixed to the inner peripheral surface of the impeller cylindrical portion 312. More specifically, the outer peripheral surface of the rotor cylindrical portion 253 of the rotor 25 is bonded to the inner peripheral surface of the impeller cylindrical portion 312, thereby fixing the impeller 30 and the rotor 25 together. Note that the impeller 30 and the rotor 25 are fixed together by bonding, but this is not limiting. For example, other fixing methods such as press fitting, welding, and screwing may also be used.

[0111] The blades 32 are arranged side by side in the circumferential direction on the outer surface of the impeller hub 31. In this embodiment, the blades 32 are arranged at equal intervals in the circumferential direction. In the impeller 30 of the blower A of this embodiment, the blades 32 and the impeller hub 31 are, for example, an integrally molded body made of resin. The upper part of the blade 32 is arranged forward of the lower part in the rotation direction Rd (see FIG. 1).

[0112] <5. Manufacturing process of the motor 20> Here, the manufacturing process of the blower A having the motor 20 will be described with reference to the drawings. Fig. 13 is a flowchart showing the manufacturing process of the blower A. As shown in Fig. 13, first, the upper end of the bearing housing 22 is press-fitted into the bearing housing mounting boss 233 of the lid portion 232 of the casing 23 (bearing housing mounting step: step S101). That is, in the bearing housing mounting step S101, the bearing housing 22 is mounted to the casing 23. In this way, the bearing housing 22 is mounted to the casing 23.

[0113] A bearing 211 is attached to the bearing housing 22 in advance, and the shaft 21 is rotatably disposed via the bearing 211. Because the bearing housing mounting boss 233 penetrates in the axial direction, the upper end of the shaft 21 attached to the bearing housing 22 protrudes above the upper end of the casing 23.

[0114] Furthermore, the bearing housing 22 and the bearing housing mounting boss 233 are in close contact with each other. This makes it possible to prevent resin from leaking from between the bearing housing 22 and the bearing housing mounting boss 233 when resin is injected in resin injection step S104, which will be described later.

[0115] In this embodiment, the bearing 211 and the shaft 21 are attached to the bearing housing 22 in advance, but this is not limiting. For example, the bearing 211 and the shaft 21 may be attached at an appropriate time after the bearing housing 22 is attached to the bearing housing mounting boss 233. However, the bearing 211 and the shaft 21 are attached to the bearing housing 22 and the bearing 211 by press-fitting. For this reason, it is preferable to attach the bearing housing 22 to the bearing housing mounting boss 233 with the bearing 211 and the shaft 21 attached to the bearing housing 22 in advance.

[0116] Next, the circuit board 40 is placed on the stator 24 (circuit board mounting step: S102). In the circuit board mounting step S102, the snap fit portions 50 of the stator 24 are inserted into the through holes 400 of the circuit board 40. The snap fit portions 50 then fit into the recesses 42. This positions the circuit board 40 relative to the stator 24 in the circumferential direction.

[0117] Then, the lower end of the insulator tubular portion 246 of the insulator 242 comes into contact with the upper surface of the circuit board 40, and the claw portions 52, 54 of the snap-fit ​​portion 50 come into contact with the lower surface of the circuit board 40. This holds the circuit board 40 in place. Thereafter, the conductor 247 at the end of the coil 243 is routed to the lower surface side of the circuit board 40 through the notch portion 43. Then, the conductor 247 is electrically connected to the land 44 on the lower surface of the circuit board 40 (see FIG. 7).

[0118] Next, the stator 24 with the circuit board 40 attached is housed inside the casing 23. FIG. 14 is a cross-sectional view of the casing 23 turned upside down with the stator 24 and circuit board 40 housed therein. As shown in FIG. 14, the inner circumferential surface of the core back portion 244 of the stator core 241 of the stator 24 is press-fitted into the outer circumferential surface of the bearing housing 22 to fix it (stator attaching step: step S103). That is, in the stator attaching step (step S103), the stator 24 is attached to at least one of the casing 23 and the bearing housing 22. Furthermore, after the circuit board arrangement step (step S102), the stator attaching step (step S103) is executed.

[0119] In the motor 20 of this embodiment, the inner peripheral surface of the core back portion 244 of the stator 24 is fixed in contact with the outer peripheral surface of the bearing housing 22, but this is not limiting. The radial outer edge of the teeth portion 245 of the stator 24 may be fixed in contact with the inner peripheral surface of the cylindrical portion 231 of the casing 23. Alternatively, both may be fixed in contact with each other.

[0120] Lead wires 45 are attached to the circuit board 40. When the circuit board 40 is housed in the casing 23, the lead wires 45 are arranged along the radial direction in a recess formed in the lower part of a first protrusion 291 that protrudes radially outward from the casing 23.

[0121] Furthermore, in the manufacturing process of this embodiment, the circuit board 40 is attached to the stator 24 in the circuit board attachment step S102, and then the stator 24 is attached to the casing 23 in the stator attachment step S103. However, this order is not limited to this. That is, the stator 24 may be attached to the casing 23 in the stator attachment step, and then the circuit board may be attached to the stator 24 in the circuit board attachment step. Even if the order is reversed in this way, the notch 43 is formed in the outer peripheral surface of the circuit board 40, and the conductor 247 can be routed below the circuit board 40 through the notch 43. This makes it easier to route the conductor 247, improving workability.

[0122] In this manner, the stator 24 and the circuit board 40 are attached inside the casing 23. Next, the casing 23 with the stator 24 and the circuit board 40 housed inside is held upside down, and resin is injected from the opening 230 located at the top (resin injection step: step S104). That is, in the resin injection step (step S104), resin is injected from the opening 230 at the lower end of the casing 23 in the axial direction, and the stator 24 is covered with resin.

[0123] In resin injection step S104, the casing 23 is placed in a reduced pressure region Dp. The reduced pressure region is a region where the pressure is lower than atmospheric pressure. For example, the internal region of a container such as a vacuum chamber can be used. The casing 23, stator 24, and circuit board 40 in FIG. 14 are assumed to be located within the reduced pressure region Dp. Then, a resin having fluidity is injected into the casing 23 within the reduced pressure region Dp.

[0124] When flowable resin is poured into the casing 23, it is necessary to prevent the flowable resin from overflowing from the casing 23. As described above, the cylindrical portion 231 of the casing 23 has the first protrusion 291 extending radially outward. The first protrusion 291 opens radially outward to form a wiring space.

[0125] When the resin having fluidity is poured into the casing 23 from the opening 230, the flow stops before the liquid surface of the resin having fluidity reaches the upper end of the inner circumferential surface of the first protruding portion 291. This makes it possible to prevent the resin having fluidity from overflowing from the casing 23.

[0126] 14, a limit line 23L of the fluid resin is defined in the casing 23. Then, in the stator mounting step S103, when the stator 24 is mounted to the casing 23, the electronic components 41 mounted on the circuit board 40 are positioned inside the casing 23, i.e., above, the limit line 23L. That is, in the resin injection step (step S104), the liquid level of the resin injected into the casing 23 with the opening 230 facing upward is positioned above the upper ends of the electronic components 41 mounted on the circuit board 40. With this configuration, the circuit board 40 and the electronic components 41 mounted on the circuit board 40 are sealed together with the stator 24 by the resin portion 60, thereby making the circuit board 40 and the electronic components 41 waterproof and preventing contact with foreign matter.

[0127] 14, the limit line 23L is set above the opening 230. That is, the lower end of the resin part 60 (the end on the cover part 26 side) is located above the opening 230 of the casing 23 (on the opposite side from the cover part 26). This configuration can prevent the resin from overflowing due to expansion and contraction during molding of the resin part 60. It also makes it possible to reliably attach the cover part 26 to the opening 230.

[0128] Then, in resin injection step S104, fluid resin is injected into the upside-down casing 23 until the upper end surface is above the upper ends of the electronic components 41 and below the limit line 23L. That is, in the resin injection step (step S104), the resin is injected with the opening 230 of the casing 23 facing upward, and the injection of the resin is completed while the upper surface of the resin injected into the casing 23 is below the upper limit of the liquid level that can be contained in the casing 23 (limit line 23L). This makes it possible to prevent the resin from overflowing from the casing 23 when the resin is injected into the casing 23. Furthermore, when the cover portion 26 is attached to the casing 23, interference between the resin portion 60 and the cover portion 26 can be prevented, allowing the cover portion 26 to be accurately attached to the casing 23.

[0129] This ensures that the fluid resin covers the stator 24, the circuit board 40, and the electronic components 41 attached to the circuit board 40. At this time, the fluid resin may also cover the lead wires 45 arranged on the first protrusions 291.

[0130] When injecting the fluid resin, the cover part 26 is not attached to the opening 230. For example, the fluid resin can be injected through the opening 230, which is larger than when a resin injection port is provided in the cover part 26. This allows the amount of fluid resin flowing in per unit time to be increased, and the injection of the resin can be completed in a short time. This prevents partial hardening from starting during injection, and prevents uneven hardening.

[0131] Furthermore, since the opening 230 is large and the injection is performed in the reduced pressure region Dp, the air inside the casing 23 is easily released when the resin is injected, and defects are less likely to occur in the resin part 60 formed by hardening the resin.

[0132] Furthermore, because the resin having fluidity is flowed into the reduced pressure region Dp, even if there are air bubbles in the resin filled in the casing 23, the air bubbles are compressed when the pressure is returned to atmospheric pressure. Therefore, the proportion of air bubbles in the resin part 60 can be reduced, and a decrease in the rigidity of the resin part 60 can be suppressed.

[0133] Next, after the casing 23 is filled with resin, the resin is hardened (resin hardening step S105). That is, immediately after the resin injection step (step S104), a resin hardening step (step S105) for hardening the injected resin is further included. That is, the casing 23 can be easily moved before the cover part 26 is attached. This can improve the work efficiency during manufacturing.

[0134] The resin curing step S105 may be performed in a reduced pressure region Dp or in an atmospheric pressure atmosphere. In addition, in the resin curing step S105, the resin may be heated or irradiated with ultraviolet light. A process according to the curing characteristics of the resin used is performed.

[0135] In resin curing step S105, the resin is cured to complete the resin part 60. At this time, the electronic components 41 are arranged on the lower surface of the circuit board 40, and the lower end of the electronic components 41 is positioned higher than the lower end of the resin part 60. Completion of the resin part 60 prevents foreign matter such as water, dust, and dirt from coming into contact with the stator 24, the circuit board 40, and the electronic components 41 attached to the circuit board 40. In other words, the waterproof and dustproof performance of the stator 24, the circuit board 40, and the electronic components 41 can be improved.

[0136] Thereafter, the lower end of the bearing housing 22 is press-fitted into the bush 262 of the cover portion 26 (cover step: step S106). That is, in the cover step (step S106), the cover portion 26 covers the opening 230 of the casing 23, and the cover step (step S106) is performed after the resin injection step (step S104).

[0137] After resin is injected through opening 230 at the bottom end of casing 23, cover part 26 is attached. Because opening 230 covers the entire bottom end of casing 23, it is easier to inject resin than when an injection port is formed in cover part 26 and resin is injected through the injection port. This allows resin to reach deep parts and narrow areas, preventing the occurrence of voids that are not filled with resin.

[0138] The cover portion 26 covers the opening 230 at the lower end of the casing 23. As a result, the opening 230 of the casing 23 is closed by the cover portion 26. A cap portion 263 is attached to the lower end of the cover portion 26. A portion of the cap portion 263 is inserted into the lower end of the bearing housing 22 to seal the bearing housing 22. This prevents foreign matter such as water, dust, and dirt from entering the bearing 211.

[0139] When the cover part 26 covers the opening 230 of the casing 23, the second protrusion 292, which is integrally molded with the cover part 26, covers the lower part of the first protrusion 291. This forms a wiring space 290 in which the lead wires 45 are arranged inside the wiring part 29. Furthermore, the upper ends of the base 261 and bushing 262 of the cover part 26 are positioned lower than the lower end of the resin part 60. This prevents interference between the cover part 26 and the resin part 60.

[0140] In this embodiment, the cover portion 26 is an integrally molded body with the second frame portion 102 of the frame 10 of the blower A. Therefore, in the cover step S106, the casing 23 on which the resin portion 60 is formed is placed inside the second frame portion 102, and the lower end portion of the bearing housing 22 is press-fitted into the bush 262. That is, the cover portion 26 has the bush 262 integrally molded radially inward of the annular base 261, and in the cover step (step S106), the lower end portion of the bearing housing 22 is press-fitted into the bush 262.

[0141] Because the metal bearing housing 22 is press-fit into the metal bushing 262, the bearing housing 22 can be firmly fixed to the cover part 26. In other words, the mounting rigidity of the bearing housing 22 to the cover part 26 can be increased. This makes it possible to suppress tilt and vibration of the shaft 21 with respect to the central axis Cx.

[0142] Then, the upper end of the shaft 21 protruding from the upper end of the bearing housing 22 is press-fitted into the shaft fixing boss 255 of the rotor 25, and the rotor 25 is attached to the shaft 21 (rotor attachment step: step S107). As a result, the magnet 252 of the rotor 25 is disposed at a fixed distance radially outward from the stator 24. The motor 20 is formed through the above procedure.

[0143] Then, the impeller cylindrical portion 312 of the impeller 30 is adhered to the outer peripheral surface of the rotor cylindrical portion 253 of the rotor 25, thereby fixing the impeller 30 to the rotor 25 (impeller fixing step: step S108).

[0144] Thereafter, the first frame portion 101 is placed on top of the second frame portion 102, and the first frame portion 101 and the second frame portion 102 are fixed together to complete the frame 10 (frame assembling step: step S109). When the first frame portion 101 is fixed above the second frame portion 102, a lead wire arrangement portion 103 is formed on the frame 10, which is formed by the first frame portion 101 and the second frame portion 102. A lead wire 45 is then arranged in the lead wire arrangement portion 103. The lead wire 45 is wired to the outside of the air blower A via the wiring portion 29 and the lead wire arrangement portion 103. This allows current from a power supply device external to the air blower A and control signals from external devices to be sent to the circuit board 40.

[0145] By using the manufacturing method for the motor 20 according to this embodiment, it is possible to pour the fluid resin before attaching the cover portion 26 to the casing 23. This allows the resin to be quickly poured into the interior of the casing 23 before the resin hardens and becomes highly viscous. This allows the resin to be widely distributed inside the casing 23, preventing the formation of spaces where no resin is present.

[0146] Furthermore, pouring the resin in a reduced pressure environment where the pressure is reduced below atmospheric pressure makes it easier for the air inside the casing 23 to be expelled to the outside. This also prevents the formation of spaces where no resin is placed. Furthermore, pouring the resin in a reduced pressure environment and curing it in an atmospheric pressure environment makes the atmospheric pressure greater than the pressure of the air inside the poured resin. This makes it possible to reduce the size of air bubbles that form inside the resin. This prevents a decrease in the rigidity of the resin part 60 after the resin has cured. Furthermore, since the formation of holes due to air bubbles can be prevented, the waterproof, dustproof, and explosion-proof properties of the motor 20 can be improved.

[0147] <6. Modifications, etc.> Fig. 15 is a plan view showing a modified recess 46 and snap-fit ​​portion 55. As shown in Fig. 15, the circumferential width of inner surfaces 461, 462 of recess 46 increases radially outward. That is, the circumferential distance between the pair of inner surfaces 461, 462 of at least one recess 46 increases radially outward. Similarly to the inner surfaces 461, 462, the circumferential width of outer surfaces 551, 552 of snap-fit ​​portion 55 also increases radially outward.

[0148] Even when such a configuration is used, the same effects as when the recess 42 and the snap-fit ​​portion 50 are used can be obtained.

[0149] Although the embodiment of the present invention has been described above, various modifications of the embodiment are possible within the scope of the spirit of the present invention. [Industrial Applicability]

[0150] The air blower of the present invention can be used as an air blower for cooling electrical equipment, etc. [Explanation of symbols]

[0151] A. Blower 10 frames 101 First frame section 102 Second frame part 103 Lead wire arrangement section 11 Frame body 111 Mounting hole 12 Wind tunnel section 121 Air intake 122 Exhaust port 13 Stator blade 20 Motor 21 Shaft 211 Bearings 22 Bearing housing 221 Bearing holder 23 Casing 23L limit line 230 Opening 231 Cylinder part 232 Lid 233 Bearing housing mounting boss 24 Stator 241 stator core 242 Insulator 243 Coil 244 Core back part 245 Teeth 246 Insulator cylinder 247 Conductor 248 Drawer Location 25 rotors 251 rotor cover 252 Magnet 253 Rotor cylinder 254 Rotor top plate 255 Shaft fixing boss 26 Cover part 261 Base 262 Bush 263 Cap part 29 Wiring section 290 Wiring space 291 1st protrusion 2911 Wiring section top plate section 2912 Wiring section side wall section 292 Second protrusion 30 impeller 31 Impeller hub 311 Lid 312 Impeller cylinder 32 Feather 40 Circuit Board 400 through holes 41 Electronic Components 42 recess 42a First recess 421 Introvert 422 1st inner surface 423 2nd inner surface 42b Second recess 424 Introvert 425 3rd inner surface 426 4th inner surface 43 Notch 44 rand 45 lead wire 50 Snap fit part 50a First snap fit part 51 Elastic support part 511 1st outer surface 512 Second outer surface 52 Claw 521 Slope 522 Contact surface 50b Second snap fit part 53 Elastic support part 531 Third outer surface 532 4th outer surface 54 Claw 541 Slope 542 Contact surface 60 Resin part Ct container Cx center axis Dp Decompression area Rd Rotation direction Sd Reference Line

Claims

1. a shaft that is rotatable around a central axis that extends vertically; a cylindrical bearing housing that rotatably supports the shaft via a bearing; a casing having a closed cylindrical shape extending in an axial direction around the central axis and holding the bearing housing; a stator disposed radially inside the casing and fixed to at least one of the casing and the bearing housing; a rotor fixed to the shaft and disposed radially outward of the casing; a cover portion that covers an opening formed at a lower end portion of the casing; a resin portion that covers the stator in a space surrounded by the bearing housing, the casing, and the cover portion; a circuit board disposed inside the casing between the stator and the opening; and a lower end portion of the circuit board and an electronic device disposed on a lower surface of the circuit board are disposed above the opening of the casing; The cover portion is A circular base and a bushing disposed radially inside the base and fixed to a lower end of an outer circumferential surface of the bearing housing, The motor has a lower end portion of the resin portion located above the opening and below a lower end portion of an electronic component disposed on the lower surface of the circuit board.

2. The motor of claim 1 , wherein at least a portion of the bushing is integrally fixed to the base.

3. a wiring section having a wiring space in which a lead wire connected to the circuit board is arranged; The wiring portion is a first protrusion extending radially outward from a lower end of the casing; a second protrusion extending radially outward from the outer circumferential surface of the base, The motor according to claim 1 or 2, wherein the second protrusion covers a lower portion of the first protrusion.

4. The stator includes: A coil and a conducting wire drawn from the coil, The outer peripheral surface of the circuit board has a notch recessed radially inward, 4. The motor according to claim 1, wherein the conductor is routed from the upper surface side to the lower surface side of the circuit board through the notch and is electrically connected to a circuit on the lower surface side of the circuit board.

5. The motor according to claim 4 , wherein the notch and the lead-out point of the conductor are offset in the circumferential direction.

6. A motor according to any one of claims 1 to 5; an impeller attached to the rotor; a frame that covers the radially outer side of the impeller, The base is integrally formed with the frame.

7. The motor according to claim 3; an impeller attached to the rotor; a frame that covers the radially outer side of the impeller, the base is integrally formed with the frame; The frame is A first frame portion; a second frame portion connected to a lower side of the first frame portion in the axial direction, the second frame portion and the base are integrally formed, a lead wire arrangement portion in which the lead wire is arranged is formed in an axial gap between the first frame portion and the second frame portion; The lead wire arrangement portion and the wiring portion are connected to each other.

8. The blower device according to claim 7 , wherein the first protrusion is in contact with at least the first frame portion.

9. a shaft that is rotatable around a central axis that extends vertically; a cylindrical bearing housing that rotatably supports the shaft via a bearing; a casing having a closed cylindrical shape extending along a central axis and configured to hold the bearing housing; a stator; A rotor, a cover portion that covers an opening at a lower end of the casing; A method for manufacturing a motor having the following features: a bearing housing mounting step of mounting the bearing housing to the casing; a stator mounting step of mounting the stator to at least one of the casing and the bearing housing; a resin injection step of injecting resin through the opening of the casing to cover the stator with the resin; a cover step that covers the opening of the casing with the cover portion, The covering step is performed after the resin injection step.

10. The cover portion is A circular base and a bushing integrally molded radially inward of the base, The motor manufacturing method according to claim 9 , wherein the covering step includes press-fitting the bushing into a lower end of the outer circumferential surface of the bearing housing.

11. A motor manufacturing method as described in claim 9 or claim 10, wherein in the resin injection step, the resin is injected with the opening of the casing facing upward, and the injection of the resin is terminated while the upper surface of the resin injected into the casing is below the upper limit of the liquid level that can be contained in the casing.

12. a circuit board placement step of placing a circuit board on the stator; After the circuit board placement step, the stator mounting step is performed; 12. The motor manufacturing method according to claim 11, wherein in the resin injection step, the upper surface of the resin injected into the casing with the opening facing upward is positioned higher than the upper ends of the electronic components mounted on the circuit board.

13. 13. The motor manufacturing method according to claim 9, further comprising a resin curing step of curing the injected resin immediately after the resin injecting step.

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