JP2023024195A - motor and blower - Google Patents

Abstract

To provide a motor capable of accurately positioning a circuit board with a simple configuration.SOLUTION: A motor includes a stator core 241, an insulator 242, a coil 243 formed by winding a conductor around the insulator 242, and a circuit board arranged on one axial side of a stator core 241 and electrically connected to the coil 243, and the circuit board includes a plurality of recesses that are recessed radially outward from the edge of a through hole formed in the center. The insulator 242 includes snap-fit portions 50a and 50b that extend toward the circuit board and fit in the recesses. The recess has an inner surface. The outer surfaces at both ends in the circumferential direction of the snap-fit portions 50a and 50b are inclined to contact with at least one inner surface of the recess.SELECTED DRAWING: Figure 8

Description

The present invention relates to a motor and an air blower using the motor.

In the conventional motor, the circuit board is attached to the insulator by inserting the engaging portion provided in the insulator attached to the stator into the center opening of the circuit board.
(See Patent Document 1, for example).

JP 2011-166857 A

However, when the circuit board is mounted by inserting the engaging portion into the opening of the circuit board, the inner peripheral surface of the opening of the circuit board is positioned by contacting the engaging portion. In this case, in order to position the circuit board accurately, it is necessary to make contact with the inner peripheral surface at least three places, which may complicate the manufacture of the insulator and the circuit board. Moreover, if the accuracy of the shape and position of the engaging portion and the shape and position of the opening of the circuit board varies, the position of the circuit board in the motor may shift.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a motor that has a simple configuration and that can accurately position a circuit board.

Another object of the present invention is to provide an air blower that can be manufactured with simple work.

An exemplary motor of the present invention includes a stator core centered on a vertically extending central axis, an insulator covering the stator core, a coil formed by winding a conductor wire around the insulator, and a coil arranged on one axial side of the stator core. and a circuit board electrically connected to the. The circuit board has a through hole formed in the center when viewed in the axial direction, and a plurality of recesses that are recessed radially outward from the peripheral edge of the through hole. The insulator has a snap fit portion that extends toward the circuit board in the axial direction and fits in the recess of the circuit board. The recess has a pair of inner side surfaces that face each other in the circumferential direction. A circumferential interval between the pair of inner side surfaces becomes narrower toward one side in the radial direction. The snap-fit portion has outer surfaces arranged at both ends in the circumferential direction. The outer surface has an inclination that contacts at least one surface of the inner surface of the recess.

An exemplary blower device of the present invention includes a motor, 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.

According to the exemplary motor of the present invention, the circuit board can be accurately positioned while having a simple configuration.

Further, according to the exemplary air blower of the present invention, it can be formed by simple work.

FIG. 1 is a perspective view showing an example of a blower device according to the present invention. 2 is an exploded perspective view of the blower shown in FIG. 1. FIG. FIG. 3 is a perspective view of the second frame. 4 is a longitudinal sectional view of the blower shown in FIG. 1. FIG. FIG. 5 is a perspective view of the casing. FIG. 6 is a plan view of the circuit board and stator. FIG. 7 is a bottom view of the circuit board. FIG. 8 is a bottom view of the stator. FIG. 9 is an exploded perspective view of the stator and the circuit board. FIG. 10 is an enlarged cross-sectional view showing an enlarged snap fit portion. FIG. 11 is an enlarged cross-sectional view of the first recess and the first snap-fit portion. FIG. 12 is an enlarged cross-sectional view of the second recess and the second snap fit portion. FIG. 13 is a flow chart showing the manufacturing process of the air blower. FIG. 14 is a cross-sectional view in which the casing in which the stator and the circuit board are accommodated is turned upside down. FIG. 15 is a plan view showing a recess and a snap fit portion of a modified example.

Exemplary embodiments of the invention are described in detail below with reference to the drawings. In this specification, in the blower A, the direction parallel to the central axis Cx of the blower A is the “axial direction”, the direction perpendicular to the central axis Cx of the blower A is the “radial direction”, and the A direction along an arc centered on the central axis Cx is defined as a “circumferential direction”. Further, in this specification, the shape and positional relationship of each part of the blower A will be described with the axial direction as the vertical direction and the intake port 121 side of the frame 10 as the top with respect to the impeller 30 . It should be noted that the vertical direction is simply a name used for explanation, and does not limit the positional relationship and direction in the usage state of the blower A. Further, "upstream" and "downstream" indicate upstream and downstream, respectively, in the flow direction of the airflow generated when the impeller 30 is rotated.

<1. Configuration of 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. FIG. 3 is a perspective view of the second frame 102. FIG. 4 is a longitudinal sectional view of the blower A shown in FIG. 1. FIG.

As shown in FIGS. 1 to 4, the blower A according to this embodiment includes a frame 10, a motor 20, and an impeller 30. As shown in FIGS. Motor 20 is fixed to frame 10 . A later-described rotor 25 of the motor 20 is rotatable with respect 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.

That is, the blower A has a motor 20 , an impeller 30 attached to a rotor 25 of the motor 20 , which will be described later, and a frame 10 that covers the radially outer side of the impeller 30 .

In the blower device A, the impeller 30 rotates in a predetermined rotation direction Rd (see FIG. 1), so that air is pushed by the blades 32 of the impeller 30, which will be described later, into the wind tunnel portion 12 of the frame 10, which will be described later. An air current is generated.

<2. Configuration of Frame 10>
As shown in FIGS. 1 to 4, the frame 10 has a frame body 11 and a wind tunnel portion 12. As shown in FIG. Note that the frame 10 in this embodiment is formed as an integrally molded body with a base 261 of a cover portion 26 of the motor 20, which will be described later. That is, the base 261 is part of the motor 20 and 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 .

The frame main body 11 is an exterior member of the air blower A. As shown in FIG. The frame body 11 is made of resin. The wind tunnel portion 12 is arranged inside the frame body 11 and has a cylindrical inner peripheral surface. As shown in FIGS. 1, 4, etc., the wind tunnel portion 12 extends along the central axis Cx. Note that the center line of the inner peripheral surface of the wind tunnel portion 12 coincides with the central axis Cx.

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

The frame main body 11 has a square rectangular parallelepiped shape when viewed from the axial direction. Mounting holes 111 are formed through the four corners of the square when viewed from the axial direction. For example, a mounting screw, boss, or the like provided in the device is inserted into the mounting hole 111 . Then, the frame main body 11 is fixed to the equipment by adopting a fixing method such as fixing a nut to the protruding portion of the screw or crimping a boss. The frame main body 11 has a square shape when viewed from the axial direction, but may have a circular shape or a polygonal shape such as a rectangle or a hexagon. A shape that matches the shape of the position where the blower A is attached to the equipment to which the blower A is attached may be adopted.

The frame 10 has a plurality of stationary blades 13 protruding radially inward from the inner peripheral surface of the wind tunnel portion 12 . The stationary blade 13 connects the wind tunnel portion 12 and the base 261 of the motor 20 . In other words, the base 261 is held by the wind tunnel section 12 via the stationary blades 13 . Airflow generated by the rotation of the impeller 30 is rectified by the stationary blades 13 .

As shown in FIGS. 1, 2, etc., the frame 10 can be separated into a first frame portion 101 and a second frame portion 102 . The first frame portion 101 is arranged above the second frame portion 102 . That is, the frame 10 has a first frame portion 101 and a 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 are not limited to this. For example, it may be fixed using a fastener such as a screw.

The frame 10 has a lead wire placement portion 103 formed by combining a first frame portion 101 and a second frame portion 102 . Lead wires 45, which will be described later, connected to a circuit board 40, which will be described later, of the motor are arranged in the lead wire arrangement portion 103. As shown in FIG.

The air blower A configured in this manner can stably discharge a constant air volume.

<3. Configuration of Motor 20>
The motor 20 is arranged 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 .

<3.1 Shaft 21>
The shaft 21 extends along the central axis Cx. The shaft 21 is columnar and has a center line that coincides with the central axis Cx. The shaft 21 is rotatably supported in the bearing housing 22 by bearings 211 at two points separated in the axial direction. That is, the shaft 21 is rotatable around the vertically extending central axis Cx.

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 . The fixing of the shaft 21 to the inner cylinder of the bearing 211 employs press-fitting here, but is not limited to this. The shaft 21 and the inner cylinder of the bearing 211 may be fixed by a fixing method such as adhesion or screwing.

The shaft 21 is rotatably supported by bearings 211 at two axially separated locations. As a result, it is possible to suppress shaft shake, shaft misalignment, and the like during rotation of the shaft 21 . This stabilizes the rotation of the shaft 21 .

<3.2 Bearing housing 22>
The bearing housing 22 is made of metal and has a cylindrical shape extending along the central axis Cx. A bearing holding portion 221 for holding the bearing 211 is provided on the inner peripheral surface of the bearing housing 22 . The bearing holding portion 221 has a stepped shape extending from the inner peripheral surface in a direction perpendicular to the central axis Cx. By bringing the outer ring of the bearing 211 into contact with the bearing holding portion 221, the bearing 211 can be axially positioned. The bearing 211 is fixed to the inner peripheral 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 adhesion. The bearing housing 22 has a cylindrical shape and rotatably supports the shaft 21 via bearings 211 .

A stator 24 is fixed to the outer peripheral surface of the bearing housing 22 . More specifically, a later-described stator core 241 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, the stator 24 and the bearing housing 22 may be fixed by a fixing method other than press fitting.

A cover portion 26 is attached to the lower end portion of the outer peripheral surface of the bearing housing 22 . A detailed description of the cover portion 26 will be given later.

<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. FIG. As shown in FIGS. 4 and 5 , the casing 23 has a cylindrical shape with a bottom extending axially about the central axis Cx, and holds the bearing housing 22 .

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

The lid portion 232 extends radially inward from the axial upper end of the cylindrical portion 231 . The lid portion 232 has bearing housing mounting bosses 233 . The bearing housing mounting boss 233 extends axially downward from the central portion of the lid portion 232 . The bearing housing mounting boss 233 is cylindrical. An upper end portion of the outer peripheral surface of the bearing housing 22 is fixed to the inner peripheral surface of the bearing housing mounting boss 233 . Although the bearing housing 22 and the bearing housing mounting boss 233 are fixed by press-fitting, the fixing method is not limited to this, and a fixing method such as adhesion or welding may be adopted.

Further, the cylindrical portion 231 of the casing 23 has a first projecting portion 291 of the wiring portion 29, which will be described later. The first projecting portion 291 is formed integrally with the tubular portion 231 . Details of the wiring portion 29 and the first projecting portion 291 will be described later.

<3.4 Cover portion 26>
The cover portion 26 extends in a direction perpendicular to the central axis Cx. The cover part 26 has a base 261 and a bush 262 . As shown in FIGS. 2 and 4, the base 261 has an annular shape. The outer edge of the base 261 connects to the radially inner end of the stationary 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 integrally molded resin bodies. That is, the second frame portion 102 and the base 261 are integrally formed.

The bush 262 is annular and arranged in the center of the base 261 . Bushing 262 is integrally formed with base 261 . That is, at least part of bush 262 may be integrally fixed to base 261 . By configuring in this way, the manufacture of the cover portion 26 is facilitated.

In addition, in this embodiment, the bush 262 is made of metal, and the base 261 is made of resin. Therefore, the cover part 26 is, for example, an insert-molded body. However, it is not limited to this, and the bush 262 may be fixed (integrated) to the base 261 by a fixing method such as adhesion or screwing. Also, in this embodiment, the bushing 262 is made of a harder material than the bearing housing 22 . However, it is not limited to this. A lower end of the bearing housing 22 is press-fitted into the bush 262 . That is, the cover portion 26 has an annular base 261 and a bush 262 arranged radially inside the base 261 and fixed to the lower end portion of the outer peripheral surface of the bearing housing 22 .

As shown in FIG. 4 and the like, the cover portion 26 has a cap portion 263 that closes the opening of the lower end portion of the bearing housing 22 . The cap portion 263 is attached to the lower surface of the base 261 of the cover portion 26 . Also, the cap portion 263 is in close contact with the inner peripheral surface of the bearing housing 22 . Here, "close contact" means a state in which no gap is formed through which foreign matter such as water, dirt, dust, etc. can pass. That is, the cover part 26 covers the opening 230 formed at the lower end of the casing 23 . In this manner, the cap portion 263 is in close contact with the opening at the lower end of the bearing housing 22 , thereby suppressing entry of foreign matter such as water, dirt, and dust into the bearing housing 22 . This allows the bearing 211 to operate stably for a long period of time.

The cover portion 26 has a second projecting portion 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 projecting portion 292 is arranged axially below the first projecting portion 291 . Details of the second projecting portion 292 will be described later.

<3.5 Stator 24>
As shown in FIG. 4 and the like, the stator 24 is housed inside a space surrounded by the bearing housing 22 , the casing 23 and the cover portion 26 . Stator 24 has stator core 241 , insulator 242 , and coil 243 .

Stator core 241 has electrical conductivity. Stator core 241 is centered on central axis Cx extending 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. Stator core 241 has an annular core back portion 244 and a plurality of teeth portions 245 . The core back portion 244 has an annular shape extending in the axial direction. The tooth portions 245 protrude radially outward from the outer peripheral surface of the core back portion 244 . The plurality of tooth portions 245 are arranged at regular intervals in the circumferential direction.

The insulator 242 is a resin molding. Insulator 242 covers at least teeth 245 of stator core 241 . That is, insulator 242 covers at least part of stator core 241 . A coil 243 is formed on the tooth portion 245 covered with the insulator 242 . That is, the coil 243 is formed by winding a conductive wire around the insulator 242 . Motor 20 is a DC brushless motor. Therefore, the three conductors 247 are drawn out from different coils 243 respectively. That is, the stator 24 has a coil 243 and a lead wire 247 drawn out from the coil 243 .

Insulator 242 insulates stator core 241 and coil 243 . In addition, in the present embodiment, the insulator 242 is a resin molding, but is not limited to this. A configuration in which stator core 241 and coil 243 can be insulated can be widely adopted.

The insulator 242 has an insulator tubular portion 246 extending axially downward. A lower end portion of the insulator cylindrical portion 246 contacts the upper surface of the circuit board 40 .

In this embodiment, the stator core 241 is fixed by press-fitting the inner peripheral surface to the outer peripheral surface of the bearing housing 22 . The stator 24 is thereby fixed to the bearing housing 22 . The fixing of the stator 24 to the bearing housing 22 is not limited to press-fitting, and a fixing method such as welding or adhesion may be employed. Moreover, in the present embodiment, the stator 24 is fixed to the bearing housing 22 , but the invention is not limited to this, 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, stator 24 may be fixed to both bearing housing 22 and casing 23 . That is, the stator 24 is arranged inside the casing 23 and fixed to at least one of the casing 23 and the bearing housing 22 .

<3.6 Rotor 25>
The rotor 25 is arranged radially outward of the stator 24 . Rotor 25 is fixed to shaft 21 . That is, the rotor 25 is fixed to the shaft 21 and arranged radially outward of the casing 23 . The rotor 25 has a rotor cover 251 and magnets 252 . The rotor cover 251 has a lidded tubular shape.

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

The rotor top plate portion 254 extends radially inward from the axial upper end of the rotor tubular portion 253 . The shaft fixing boss 255 is arranged in the central portion of the rotor top plate portion 254 when viewed in the axial direction. The shaft fixing boss 255 and the rotor top plate portion 254 are integrally molded. The shaft fixing boss 255 has a cylindrical shape penetrating in the axial direction. The shaft 21 passes through 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 . Thereby, the rotor cover 251 of the rotor 25 is fixed to the shaft 21 .

As shown in FIGS. 2, 4, etc., the magnet 252 is cylindrical. The magnet 252 has a tubular shape magnetized alternately with N poles and S poles in the circumferential direction. The magnet 252 has its outer peripheral surface fixed to the inner peripheral surface of the rotor tubular portion 253 .

In this embodiment, the magnet 252 is an integrally molded body of resin mixed with magnetic powder. However, it is not limited to this configuration, and a plurality of magnets may be arranged in the circumferential direction and fixed with resin or the like.

As described above, in the motor 20 of this embodiment, the rotor 25 is arranged radially outward of the stator 24 . The rotor 25 then rotates around the stator 24 . That is, the motor 20 is an outer rotor type motor.

An impeller 30 is attached to the outside of the rotor cover 251 . Impeller 30 is fixed to rotor cover 251 by, for example, adhesion. Thereby, the impeller 30 rotates because the rotor 25 rotates. Note that the fixing between the impeller 30 and the rotor cover 251 is not limited to adhesion, and may be fixed by a fixing method such as press fitting, welding, or welding.

<3.7 Configuration of Circuit Board 40>
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. FIG. In the circuit board 40 shown in FIG. 7, the conducting wire 247 is indicated by a dashed line. The circuit board 40 is annular. An electronic component 41 is mounted on the surface of the circuit board 40 to form a control circuit for supplying power to the coil 243 .

A through hole 400 is formed through the center of the circuit board 40 in the axial direction. The bearing housing 22 passes through the through hole 400 . As shown in FIG. 4 and the like, the circuit board 40 is arranged below the stator 24 and held by insulators 242 of the stator 24 . That is, the circuit board 40 is arranged on one axial side of the stator core 241 . At this time, the circuit board 40 is arranged inside the casing 23 . That is, the motor 20 further has a circuit board 40 arranged inside the casing 23 .

The circuit board 40 has a recess 42 that is recessed radially outward from the edge of the through hole 400 . That is, the circuit board 40 has a through hole 400 formed in the central portion when viewed in the axial direction, and a plurality of recesses 42 that are recessed radially outward from the peripheral edge portion of the through hole 400 .

A snap-fit portion 50 provided on the insulator 242 is accommodated in the concave portion 42 . The circuit board 40 is held by the stator 24 by fitting the snap-fit portion 50 into the recess 42 . The details of the concave portion 42 and the snap fit portion 50 will be described later.

The outer peripheral surface of the circuit board 40 has a cutout portion 43 that is recessed radially inward. Different conductors 247 are arranged in the cutouts 43 , and the ends of the conductors 247 are wired on the lower surface side of the circuit board 40 . The tip of the conductor 247 is electrically connected to the land 44 arranged on the bottom surface of the circuit board 40 (see FIG. 7). That is, circuit board 40 is electrically connected to coil 243 . Conducting wire 247 is routed from the upper surface side to the lower surface side of circuit board 40 through notch 43 and is electrically connected to the circuit (land 44 ) on the lower surface side of circuit board 40 . The electrical connection between the conducting wire 247 and the land 44 is made by soldering, for example. However, the connection between the conducting wire 247 and the land 44 is not limited to soldering, and bonding with a conductive adhesive, screwing, or the like may be employed.

Since the circuit board 40 has the cutout portion 43 , the lead wire 247 can be wired on the lower surface of the circuit board 40 via the cutout portion 43 . This facilitates wiring of the conductor 247 to the lower surface of the circuit board 40 compared to the case where the circuit board 40 is provided with a hole through which the conductor 247 passes instead of the notch 43 . For example, after mounting the circuit board 40 below the stator 24 , the conductor 247 is routed to the lower surface of the circuit board 40 . At this time, since the conductor 247 is wired in the notch 43 that is open at the radial outer edge of the circuit board 40, the stator 24 is less likely to be an obstacle, and the wiring of the conductor 247 is facilitated.

The stator 24 has a lead-out portion 248 through which a conductor wire is led out from the coil 243 . Three extraction points 248 are provided on the stator 24 . A different lead wire 247 is led out from each lead-out point 248 .

As shown in FIG. 6, when the circuit board 40 is attached to the stator 24, the notch 43 and the lead-out portion 248 are displaced in the circumferential direction. By configuring in this way, the conducting wire 247 can be wired along the tangential direction of the core back portion 244 of the stator core 241 . As a result, interference between the conducting wire 247 and members such as the casing 23 is suppressed, and disconnection of the conducting wire 247 is suppressed.

A lead wire 45 is connected to the circuit board 40 (see FIG. 4). That is, the motor 20 further has leads 45 connected to the circuit board. The lead wire 45 connects the circuit board 40 and a power supply device arranged outside the motor 20 , in other words, outside the blower A.

<3.8 Concave portion 42 and snap fit portion 50>
8 is a bottom view of the stator 24. FIG. FIG. 9 is an exploded perspective view of the stator 24 and the circuit board 40. As shown in FIG. FIG. 10 is an enlarged cross-sectional view of the snap fit portion 50. As shown in FIG. As shown in FIGS. 8 and 9, insulator 242 has two snap-fit portions 50 . The circuit board 40 has two recesses 42 . The snap-fit portion 50 fits into the recess 42 formed in the through-hole 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 in the recess 42 of the circuit board 40 . Also, the insulator 242 has two snap-fit portions 50 and the circuit board 40 has two recesses 42 .

The circuit board 40 has two recesses 42 with different shapes. That is, the circuit board 40 has at least one concave portion 42 whose shape when viewed from the axial direction is different from the other concave portions 42 .

In the following description, regarding the two recesses 42, one recess 42 is the first recess 42a (see FIGS. 7 and 9), and the other recess 42 is the second recess 42b (FIGS. 7 and 9). etc.). Further, the two snap-fit portions 50 are, if necessary, a first snap-fit portion 50a that fits in the first recess 42a and a second snap-fit portion 50b that fits in the second recess 42b.

FIG. 11 is an enlarged 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 defined as a reference line Sd.

As shown in FIG. 11, the first recess 42a has an inward surface 421, and a first inner surface 422 and a second inner surface 423 facing each other in the circumferential direction. That is, the recess 42a (42b) has a pair of inner side surfaces (a first inner side surface 422 and a second inner side surface 423, a third inner side surface 425 and a fourth inner side surface 426) facing each other in the circumferential direction. The inward surface 421 radially faces the center of the through hole 400 . Also, 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.

In the first concave portion 42a, the interval between the first inner side surface 422 and the second inner side surface 423 becomes narrower as it goes radially outward. That is, the circumferential interval between the first inner side surface 422 and the second inner side surface 423 becomes narrower toward one side in the radial direction. The first inner side surface 422 and the second inner side surface 423 approach each other as they go radially outward. More specifically, when viewed from the axial direction, the first inner side surface 422 and the second inner side surface 423 are inclined with respect to the reference line Sd and are line symmetric with respect to the reference line Sd. That is, the first inner side surface 422 and the second inner side surface 423 of at least one recess 42a are arranged line-symmetrically with respect to the reference line Sd. Note that the first inner side surface 422 and the second inner side surface 423 may not be line-symmetrical.

In addition, although the width|variety of the circumferential direction of the 1st inner surface 422 and the 2nd inner surface 423 becomes narrow toward radial direction outward as the 1st recessed part 42a, it is not limited to this. As will be described later in detail, for example, the width of the first inner side surface 422 and the second inner side surface 423 in the circumferential direction may be narrowed radially inward (see FIG. 15).

FIG. 12 is an enlarged sectional view of the second recess 42b and the second snap fit portion 50b. In FIG. 12, as in FIG. 11, a line passing through the center (central axis Cx) of the through-hole 400 and extending in the radial direction is defined as a reference line Sd.

As shown in FIG. 12, the second recess 42b has an inward surface 424, and a third inner surface 425 and a fourth inner surface 426 facing each other in the circumferential direction. The inward facing surface 424 faces radially toward the center of the through hole 400 . In addition, the third inner side surface 425 and the fourth inner side 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.

In the second concave portion 42b, the interval between the third inner side surface 425 and the fourth inner side surface 426 becomes narrower as it goes radially outward. That is, the circumferential interval between the third inner surface 425 and the fourth inner surface 426 becomes narrower toward one side in the radial direction. The third inner side surface 425 extends parallel to the reference line Sd. That is, one inner side surface 425 of at least one recessed portion 42b extends parallel to the reference line Sb extending in the radial direction through the center of the through hole (central axis Cx). Note that the term “parallel” here includes not only the case of being completely parallel, but also the case of being inclined by several degrees to ten and several degrees. Also, the inner surface 426 approaches the inner surface 425 as it goes radially outward.

As shown in FIGS. 9, 11, etc., the first snap fit portion 50a has an elastic support portion 51 and a claw portion 52. As shown in FIGS. 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.

The elastic support portion 51 has a first outer side surface 511 and a second outer side surface 512 arranged at both ends in the circumferential direction. That is, the snap-fit portion 50a has outer surfaces (a first outer surface 511 and a second outer surface 512) arranged at both ends in the circumferential direction. 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 radially outward. Then, the first outer surface 511 and the second outer surface 512 approach each other as they go radially outward. The first outer surface 511 and the second outer surface 512 are symmetrical with respect to a line passing through the center of the elastic support portion 51 in the circumferential direction (the reference line Sd in FIG. 11).

The claw portion 52 protrudes radially outward from the lower end portion 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 slopes radially outward as it goes upward. Also, the contact surface 522 is perpendicular to the central axis Cx and contacts the upper end of the inclined surface 521 .

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 contacts the inward surface 421 of the first recess 42a. Furthermore, when the first snap fit portion 50a is moved downward, the inclined surface 521 is pushed by the inward surface 421, and the elastic support portion 51 is elastically deformed radially inward. As a result, the claw portion 52 of the first snap fit portion 50a passes through the first concave portion 42a.

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 contacts the lower surface of the circuit board 40 . At this time, the lower surface of insulator cylinder portion 246 contacts the upper surface of circuit board 40 .

When the claw portion 52 passes through the first recess 42a, the first outer surface 511 of the elastic support portion 51 contacts the first inner surface 422 of the first recess 42a, and the second outer surface 512 contacts the second inner surface 423. Contact. 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) contacts at least one of the inner surfaces (the first inner surface 411 and the second inner surface 412) of the recess 42a.

In addition, when viewed from the axial direction, the snap fit portion 50 may be configured to contact at least one of the first inner side surface 411 and the second inner side surface 412 at a point. Even with such a configuration, the snap fit portion 50 is positioned before contacting the inward surface 421 . As a result, the circuit board 40 can be positioned even if the shapes of the recess 42a and the snap-fit portion 50 vary.

As shown in FIGS. 9, 12, etc., the second snap fit portion 50b has an elastic support portion 53 and a claw portion 54. As shown in FIGS. The elastic support portion 53 extends downward from the lower end portion of the insulator tubular portion 246 along the central axis Cx. The elastic support portion 53 is elastically bendable.

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

The claw portion 54 has a configuration similar to that of 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, respectively. Therefore, details of the claw portion 54 are omitted.

As shown in FIGS. 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 contacts the inward surface 424 of the second recess 42b. Further, when the second snap fit portion 50b is moved downward, the inclined surface 541 is pushed by the inward surface 424, and the elastic support portion 53 is elastically deformed radially inward. As a result, the claw portion 54 of the second snap fit portion 50b passes through the second concave portion 42b.

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 contacts the lower surface of the circuit board 40 . At this time, the lower surface of insulator cylinder portion 246 contacts the upper surface of circuit board 40 .

When the claw portion 54 passes through the second recess 42b, the third outer surface 531 of the elastic support portion 53 contacts the third inner surface 425 of the second recess 42b, and the fourth outer surface 532 contacts the fourth inner surface 426. Contact. That is, at least one of the outer surfaces (the third outer surface 531 and the fourth outer surface 532) contacts at least one of the inner surfaces (the third inner surface 431 and the fourth inner surface 432) of the recess 42b. Thereby, the second snap fit portion 50b and the second concave portion 42b are positioned in the circumferential direction. The second snap fit portion 50b is radially spaced from the inward facing surface 424 of the second recess 42b.

By fitting the two snap-fit portions 50 into the corresponding recesses 42 in this way, the circuit board 40 is attached to the stator 24 . Specifically, the lower surface of the insulator cylindrical portion 246 contacts the upper surface of the circuit board 40 . The contact surface 522 of the claw portion 52 of the first snap fit portion 50 a and the contact surface 542 of the claw portion 54 of the second snap fit portion 50 b contact 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 portion 50 .

The first outer surface 511 and the second outer surface 512 of the elastic support portion 51 of the first snap-fit portion 50a are in contact with the first inner surface 422 and the second inner surface 423 of the first recess 42a. Thereby, the first recess 42a is held in the circumferential direction with respect to the first snap fit portion 50a. The circuit board 40 is held by contact between the radially inclined first outer surface 511 and the second outer surface 512 and the radially inclined first inner surface 422 and the second inner surface 423 . Therefore, even if there are variations in the radial thickness of the first snap-fit portion 50a, the radial length of the first concave portion 42a, and the circumferential positions of the first inner side surface 422 and the second inner side surface 423, the circuit board 40 can be accurately positioned in the circumferential direction. In addition, since the first inner side surface 422 and the second inner side surface 423 of the recess 42a and the first outer side surface 511 and the second outer side surface 512 of the snap fit portion 50a are formed in line symmetry, 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 between the first inner surface 422 and the second inner surface 423 and the first outer surface 511 and the second outer surface 512 The force becomes almost uniform. Therefore, it is possible to improve the positioning accuracy of the circuit board 40 in the circumferential direction.

In addition, the third outer surface 531 and the fourth outer surface 532 of the elastic support portion 53 of the second snap-fit portion 50b are in contact with the third inner surface 425 and the fourth inner surface 426 of the second recess 42b. Thereby, the second recessed portion 42b is held in the circumferential direction with respect 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 inner surface 426 of the radially inclined fourth inner surface 426 . Therefore, even if there are variations in the radial thickness of the second snap-fit portion 50b, the radial length of the second recess 42b, and the circumferential positions of the third inner surface 425 and the fourth inner surface 426, the circuit board 40 can be positioned accurately. In addition, since the third outer surface 531 is in contact with the third inner surface 425 of the second recess 42b, the movement of the circuit board 40 in the circumferential direction can be effectively restricted.

Since the circuit board 40 is held in the circumferential direction at two different locations in the circumferential direction, movement in the circumferential direction is restricted. With this configuration, the snap fit portion 50 can position the circuit board 40 in the circumferential direction with respect to the insulator 242 . Therefore, the positioning member and recess can be omitted.

With the above configuration, the first outer surface 511 and the second outer surface 512 of the first snap fit portion 50a and the first inner surface 422 and the second inner surface 423 of the first recess 42a are in contact with each other in the circumferential direction. Further, the third outer surface 531 and the fourth outer surface 532 of the second snap fit portion 50b and the fourth inner surface 426 of the second recess 42b are in contact with each other in the circumferential direction. Therefore, the two snap-fit portions 50a, 50b and the two recesses 42a, 42b can precisely position the circuit board 40 in the circumferential direction. Therefore, the number of snap fit portions 50 and recesses 42 can be reduced. By reducing the number of recesses, the area of the circuit board 40 where the recesses are formed can be reduced, and the area of the portion where the wiring pattern is formed can be increased, and the degree of freedom of the wiring pattern can be increased.

In addition, the two recesses 42 and the two snap-fit portions 50 have different shapes, so that the circuit board 40 can be attached to the stator 24 in the correct orientation and position.

In addition, by making one inner surface (third inner surface 425) of the second recess 42b parallel to the reference line Sb, the inner surface (third inner surface 425) of the recess 42b and the outer surface of the snap fit portion 50b ( Circumferential positioning accuracy with respect to the third outer surface 531) can be increased.

The circumferential interval between the pair of inner side surfaces of at least one recess 42 narrows in the circumferential direction toward the radially outward direction. With this configuration, the pair of inner side surfaces of the recess 42 and the outer side surface of the snap fit portion 50 are brought into contact with each other, so that the snap fit portion 50 is arranged inside the recess 42 . Therefore, the snap-fit portion 50 can easily enter the recess from the radially inner side, improving workability.

<3.9 Configuration of Wiring Portion 29>
The wiring portion 29 protrudes radially outward from the radial outer edge of the casing 23 when viewed in the axial direction. The wiring portion 29 has a wiring space 290 in which the lead wires 45 are arranged. That is, the motor 20 further has a wiring portion 29 having a wiring space 290 in which the lead wires 45 are arranged.

The wiring portion 29 has a first projecting portion 291 and a second projecting portion 292 . As described above, the first projecting portion 291 and the second projecting portion 292 are integrally formed with the casing 23 and the cover portion 26, respectively. When the first projecting portion 291 and the second projecting portion 292 are stacked vertically, a wiring space 290 extending in the radial direction is formed inside the wiring portion 29 .

The wiring portion 29 has a first projecting portion 291 extending radially outward from the lower end portion of the casing 23 and a second projecting portion 292 extending radially outward from the outer peripheral surface of the base 261 .

More specifically, the first projecting portion 291 has a wiring top plate portion 2911 and a pair of wiring portion side wall portions 2912 . The wiring section top plate section 2911 has a plate-like shape extending in a direction intersecting with the central axis Cx. When viewed from the axial direction, the wiring section top plate section 2911 has a rectangular shape extending in the axial direction. The pair of wiring portion side wall portions 2912 extends axially downward from both ends of the wiring portion top plate portion 2911 in the circumferential direction. The wiring section top plate section 2911 and the pair of wiring section side wall sections 2912 are integrally molded. The axial lower surface of the first projecting portion 291 is recessed axially upward and radially.

The second projecting portion 292 has a plate-like shape extending in a direction intersecting with the central axis Cx. The second projecting portion 292 has a rectangular shape and is arranged to face the wiring portion top plate portion 2911 of the first projecting portion 291 in the axial direction.

The wiring portion 29 is arranged in contact with the axial lower ends of the pair of wiring portion side wall portions 2912 of the first projecting portion 291 . That is, the second projecting portion 292 covers the depression of the lower surface of the first projecting portion 291 . Thereby, a wiring space 290 extending in the radial direction is formed in the wiring portion 29 . Note that the wiring section top plate section 2911 and the second protruding section 292 are in close contact with each other. As a result, foreign substances such as water, dust, and dirt are prevented from entering the wiring space 290 of the wiring portion 29 . Also, the inflow of the airflow generated by the impeller 30 is suppressed.
A wiring portion 29 formed on the casing 23 and the base 261 holds the lead wire 45 .
In other words, the lead wire 45 is reliably held by the casing 23 and the base 261 . By securely holding the lead wire 45 , the force acting on the lead wire 45 is applied to the wiring portion 29 even when a force that pulls the lead wire 45 acts. Therefore, the force acting on the connecting portion between the lead wire 45 and the circuit board 40 is reduced. As a result, detachment of the lead wire 45 from the circuit board 40 can be suppressed.

A lead wire arrangement portion 103 in which the lead wire 45 is arranged is formed in an axial gap between the first frame portion 101 and the second frame portion 102 , and the lead wire arrangement portion 103 and the wiring portion 29 are connected. By configuring in this way, the lead wire 45 can be stably held.

Note that the first projecting portion 291 may be in contact with at least the first frame portion 101 . By configuring in this way, wind leakage to the lead wire arrangement portion 103 can be suppressed.

<3.10 Structure of Resin Portion 60>
A stator 24 and a circuit board 40 are arranged in a space surrounded by the casing 23 , the bearing housing 22 and the cover portion 26 . Then, after the stator 24 and the circuit board 40 are arranged at the correct positions, the molten resin is allowed to flow into the casing 23 . Then, the resin portion 60 is formed by curing the resin. That is, the resin portion 60 covers the stator 24 within the space surrounded by the bearing housing 22 , the casing 23 and the cover portion 26 .

That is, in the motor 20 according to this embodiment, the stator 24 and the circuit board 40 housed in the casing 23 are sealed by the resin portion 60 . The motor 20 has the configuration shown above.

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 applied to the axial upper end portion and the axial lower end portion of the bearing housing 22 are balanced, and vibration of the motor 20 is suppressed. Also, when connecting the bearing housing 22 and the cover portion 26 , the bushing 262 is connected between the base 261 and the bearing housing 22 . Thereby, deformation of the bearing housing 22 and the base 261 can be suppressed by the force acting when the bearing housing 22 and the cover portion 26 are connected.

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

As shown in FIGS. 1, 2, etc., the impeller hub 31 includes a lid portion 311 and an impeller cylinder portion 312 . The lid portion 311 has a disc shape that expands in the radial direction. The impeller tubular portion 312 has a tubular shape extending axially downward from the radial outer edge of the lid portion 311 .

A rotor 25 is fixed to the inner peripheral surface of the impeller tubular portion 312 . More specifically, the impeller 30 and the rotor 25 are fixed by bonding the outer peripheral surface of the rotor tubular portion 253 of the rotor 25 to the inner peripheral surface of the impeller tubular portion 312 . Although the impeller 30 and the rotor 25 are each fixed by adhesion, the fixing is not limited to this. For example, a fixing method such as press-fitting, welding, or screwing may be employed.

The plurality of 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 regular intervals in the circumferential direction. In the impeller 30 of the blower device A of this embodiment, the blades 32 and the impeller hub 31 are, for example, an integrally molded body of resin. The upper portion of the blade 32 is arranged ahead of the lower portion in the rotational direction Rd (see FIG. 1).

<5. Manufacturing Process of Motor 20>
Here, the manufacturing process of the air blower A having the motor 20 will be described with reference to the drawings. FIG. 13 is a flow chart showing the manufacturing process of the air blower A. As shown in FIG. 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 cover 232 of the casing 23 (bearing housing mounting step: step S101). That is, the bearing housing attachment step S101 attaches the bearing housing 22 to the casing 23 . The bearing housing 22 is thereby attached to the casing 23 .

A bearing 211 is attached to the bearing housing 22 in advance, and the shaft 21 is rotatably arranged via the bearing 211 . Since 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 .

Also, the bearing housing 22 and the bearing housing mounting boss 233 are in close contact with each other. As a result, it is possible to prevent the resin from leaking from between the bearing housing 22 and the bearing housing mounting boss 233 when the resin is injected in the resin injection step S104, which will be described later.

Although the bearing 211 and the shaft 21 are attached in advance to the bearing housing 22 in this embodiment, the present invention is not limited to this. For example, the bearing 211 and the shaft 21 may be attached at an appropriate timing after the bearing housing 22 is attached to the bearing housing attachment boss 233 . However, bearing 211 and shaft 21 are attached to bearing housing 22 and bearing 211 by press fitting. Therefore, it is preferable to attach the bearing housing 22 to the bearing housing attachment boss 233 with the bearing 211 and the shaft 21 already attached to the bearing housing 22 .

Next, the circuit board 40 is placed on the stator 24 (circuit board mounting step: S102). In the circuit board mounting step S<b>102 , the snap fit portion 50 of the stator 24 is inserted into the through hole 400 of the circuit board 40 . The snap fit portion 50 then fits into the recess 42 . Thereby, the circuit board 40 is circumferentially positioned with respect to the stator 24 .

The lower end portion of the insulator cylindrical portion 246 of the insulator 242 contacts the upper surface of the circuit board 40 , and the claw portions 52 and 54 of the snap fit portion 50 contact the lower surface of the circuit board 40 . Thereby, the circuit board 40 is held. After that, the conductor wire 247 at the end of the coil 243 is routed to the lower surface side of the circuit board 40 via the notch portion 43 . Conductive wire 247 is then electrically connected to land 44 on the bottom surface of circuit board 40 (see FIG. 7).

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 in which the stator 24 and the circuit board 40 are housed and which is turned upside down. As shown in FIG. 14, the inner peripheral surface of the core back portion 244 of the stator core 241 of the stator 24 is press-fitted into the outer peripheral surface of the bearing housing 22 and fixed (stator mounting step: step S103). That is, the stator mounting step (step S103) mounts the stator 24 to at least one of the casing 23 and the bearing housing 22. FIG. Further, after the circuit board arrangement step (step S102), the stator attachment step (step S103) is executed.

In addition, in the motor 20 of the present embodiment, the inner peripheral surface of the core back portion 244 of the stator 24 is brought into contact with the outer peripheral surface of the bearing housing 22 and fixed, but the present invention is not limited to this. The radial outer edge portion of the tooth portion 245 of the stator 24 may be brought into contact with the inner peripheral surface of the tubular portion 231 of the casing 23 and fixed. Moreover, both may be brought into contact and fixed.

A lead wire 45 is attached to the circuit board 40 . When the circuit board 40 is accommodated in the casing 23 , the lead wires 45 are radially arranged in recesses formed under the first projections 291 projecting radially outward from the casing 23 .

Further, in the manufacturing process of this embodiment, after the circuit board 40 is attached to the stator 24 in the circuit board attachment step S102, the stator 24 is attached to the casing 23 in the stator attachment step S103. However, it is not limited to this order. That is, after the stator 24 is attached to the casing 23 in the stator attachment step, the circuit board may be attached to the stator 24 in the circuit board attachment step. Even if the order is reversed in this manner, the cutout portion 43 is formed on the outer peripheral surface of the circuit board 40 , and the lead wire 247 can be routed below the circuit board 40 through the cutout portion 43 . Therefore, the conductor 247 can be easily handled, and workability can be improved.

The stator 24 and the circuit board 40 are attached inside the casing 23 as described above. Next, the casing 23 in which the stator 24 and the circuit board 40 are housed is held upside down, and resin is injected through the opening 230 located at the top (resin injection step: step S104). That is, in the resin injection step (step S104), the resin is injected from the opening 230 at the lower end in the axial direction of the casing 23 to cover the stator 24 with the resin.

In the resin injection step S104, the casing 23 is placed in the reduced pressure area Dp. Note that the reduced pressure region is a region where the pressure is lower than the atmospheric pressure. For example, an interior region of a container that can be evacuated inside, such as a vacuum chamber, can be used. It is assumed that the casing 23, the stator 24 and the circuit board 40 in FIG. 14 are within the reduced pressure region Dp. Then, a fluid resin is injected into the casing 23 within the depressurized region Dp.

When flowing resin having fluidity into casing 23 , it is necessary to prevent the resin having fluidity from overflowing from casing 23 . As described above, the cylindrical portion 231 of the casing 23 has the first projecting portion 291 extending radially outward. The first projecting portion 291 is open radially outward to form a wiring space.

When the liquid resin is poured into the casing 23 from the opening 230 , the flow is stopped before the liquid surface of the liquid resin reaches the upper end of the inner peripheral surface of the first protrusion 291 . As a result, it is possible to prevent the fluid resin from overflowing from the casing 23 .

As shown in FIG. 14, in the casing 23, a limit line 23L of fluid resin is defined. Then, in the stator attachment step S103, when the stator 24 is attached to the casing 23, the electronic component 41 attached to the circuit board 40 is located inside the casing 23, that is, above the limit line 23L. That is, in the resin injection step (step S104), the liquid surface of the resin injected into the casing 23 with the opening 230 directed upward is positioned above the upper end of the electronic component 41 mounted on the circuit board 40. . With this configuration, the circuit board 40 and the electronic component 41 mounted on the circuit board 40 are sealed together with the stator 24 by the resin portion 60, so that the circuit board 40 and the electronic component 41 can be waterproofed and the contact of foreign matter can be suppressed. .

As shown in FIG. 14, the limit line 23L is set above the opening 230. As shown in FIG. That is, the lower end of the resin portion 60 (the end on the cover portion 26 side) is located above the opening portion 230 of the casing 23 (on the side opposite to the cover portion 26). With this configuration, it is possible to prevent the resin from overflowing due to expansion and contraction of the resin portion 60 during molding. Moreover, it is possible to securely attach the cover portion 26 to the opening portion 230 .

Then, in the 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 injecting step (step S104), the resin is injected with the opening 230 of the casing 23 facing upward, and the upper surface of the resin injected into the casing 23 is the upper limit of the liquid level that can be accommodated in the casing 23. (Limit line 23L), the injection of the resin is finished while it is below (limit line 23L). Thereby, it is possible to prevent the resin from overflowing from the casing 23 when the resin is injected into the casing 23 . Moreover, when attaching the cover portion 26 to the casing 23 , interference between the resin portion 60 and the cover portion 26 can be suppressed, and the cover portion 26 can be attached to the casing 23 accurately.

As a result, the fluid resin reliably covers the stator 24, the circuit board 40, and the electronic component 41 to which the circuit board 40 is attached. At this time, the fluid resin may cover the lead wires 45 arranged on the first projecting portion 291 .

Note that the cover portion 26 is not attached to the opening portion 230 when the fluid resin is injected. For example, the fluid resin can be injected through the opening 230 which is larger than when the resin injection port is provided in the cover portion 26 . Therefore, it is possible to increase the inflow amount of the resin having fluidity per unit time, and to complete the injection of the resin in a short time. Therefore, it is possible to suppress the initiation of partial curing in the middle of injection, and to suppress unevenness in curing.

In addition, since the opening 230 is large and the injection is performed in the depressurized region Dp, air inside the casing 23 is easily released when the resin is injected, and defects in the resin portion 60 formed by curing the resin are eliminated. difficult to form.

Furthermore, since the fluid resin is allowed to flow into the pressure reduction region Dp, even if there are air bubbles in the resin filled in the casing 23, the air bubbles are compressed when returning to the atmospheric pressure. Therefore, the ratio of air bubbles in the resin portion 60 can be reduced, and a decrease in rigidity of the resin portion 60 can be suppressed.

Next, after the casing 23 is filled with resin, the resin is cured (resin curing step S105). That is, the method further includes a resin curing step (step S105) for curing the injected resin immediately after the resin injecting step (step S104). That is, the casing 23 can be easily moved before the cover portion 26 is attached. As a result, work efficiency during manufacturing can be enhanced.

The resin curing step S105 may be performed within the reduced pressure region Dp, or may be performed in an atmosphere of atmospheric pressure. Further, in the resin curing step S105, the resin may be heated or irradiated with ultraviolet rays. Treatment is performed according to the curing characteristics of the resin used.

In the resin curing step S105, the resin is cured and the resin portion 60 is completed. At this time, the electronic component 41 is arranged on the lower surface of the circuit board 40 , and the lower end portion of the electronic component 41 is located above the lower end portion of the resin portion 60 . By completing the resin portion 60 , the stator 24 , the circuit board 40 , and the electronic components 41 attached to the circuit board 40 are prevented from coming into contact with foreign matter such as water, dust, and dirt. In other words, the waterproof and dustproof performance of the stator 24, the circuit board 40 and the electronic component 41 can be enhanced.

After that, the lower end portion of the bearing housing 22 is press-fitted into the bush 262 of the cover portion 26 (cover step: step S106). That is, the cover step (step S106) covers the opening 230 of the casing 23 with the cover portion 26, and the cover step (step S106) is executed after the resin injection step (step S104).

After injecting resin from the opening 230 at the lower end of the casing 23, the cover 26 is attached. Since the opening 230 is the entire lower end portion of the casing 23, it is easier for the resin to flow in than when an injection port is formed in the cover portion 26 and the resin is injected from the injection port. Therefore, it is possible to spread the resin even in deep parts and narrow areas, and it is possible to suppress the occurrence of gaps not filled with the resin.

Also, the cover part 26 covers the opening 230 at the lower end of the casing 23 . Thereby, 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 portion of the bearing housing 22 to seal the bearing housing 22 . As a result, foreign substances such as water, dust, and dirt are prevented from entering the bearing 211 .

When the cover portion 26 covers the opening 230 of the casing 23 , the second projecting portion 292 integrally molded with the cover portion 26 covers the lower portion of the first projecting portion 291 . Thereby, a wiring space 290 in which the lead wire 45 is arranged is formed inside the wiring portion 29 . Also, the upper ends of the base 261 and the bush 262 of the cover portion 26 are arranged below the lower end portion of the resin portion 60 . Thereby, interference between the cover portion 26 and the resin portion 60 is suppressed.

In this embodiment, the cover portion 26 is integrally formed with the second frame portion 102 of the frame 10 of the blower A. As shown in FIG. Therefore, in cover step S<b>106 , the casing 23 with the resin portion 60 formed therein is arranged 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 a bush 262 integrally molded radially inward of an annular base 261, and the lower end portion of the bearing housing 22 is press-fitted into the bush 262 in a cover step (step S106).

Since the bearing housing 22 made of metal is press-fitted into the bush 262 which is also made of metal, the bearing housing 22 can be firmly fixed to the cover portion 26 . In other words, the mounting rigidity of the bearing housing 22 with respect to the cover portion 26 can be increased. As a result, tilting and swinging of the shaft 21 with respect to the central axis Cx can be suppressed.

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 to attach the rotor 25 to the shaft 21 (rotor attachment step: step S107). As a result, the magnets 252 of the rotor 25 are arranged radially outward of the stator 24 with a certain distance therebetween. The motor 20 is formed by the above procedure.

Then, the impeller tubular portion 312 of the impeller 30 is adhered to the outer peripheral surface of the rotor tubular portion 253 of the rotor 25 to fix the impeller 30 to the rotor 25 (impeller fixing step: step S108).

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 to complete the frame 10 (frame assembly step: step S109). When the first frame portion 101 is fixed above the second frame portion 102 , the lead wire placement portion 103 formed by the first frame portion 101 and the second frame portion 102 is formed in the frame 10 . A lead wire 45 is arranged in the lead wire arrangement portion 103 . The lead wire 45 is wired to the outside of the blower A via the wiring portion 29 and the lead wire placement portion 103 . Thereby, the current from the power supply device outside the blower A and the control signal from the external device can be sent to the circuit board 40 .

By using the method for manufacturing the motor 20 according to the present embodiment, the fluid resin can be poured before the cover portion 26 is attached to the casing 23 . As a result, the resin can be quickly poured into the casing 23 before the resin hardens and becomes highly viscous. Therefore, the resin can be spread widely inside the casing 23, and the formation of a space where the resin is not arranged can be suppressed.

In addition, when the resin is poured in, the air inside the casing 23 is easily discharged to the outside when the resin is poured in by performing the resin in a reduced pressure environment that is lower than the atmospheric pressure. Also from this, it is possible to suppress the formation of a space where the resin is not arranged. Furthermore, by pouring the resin under a reduced pressure environment and curing it under an atmospheric pressure environment, the atmospheric pressure becomes higher than the pressure of the air inside the poured resin. Therefore, it is possible to reduce the size of air bubbles formed inside the resin. Thereby, it is possible to suppress a decrease in rigidity of the resin portion 60 after the resin is cured. Moreover, since the formation of holes due to air bubbles can be suppressed, the waterproofness, dustproofness, and explosionproofness of the motor 20 can be enhanced.

<6. Modifications, etc.>
FIG. 15 is a plan view showing the recessed portion 46 and the snap fit portion 55 of the modified example. As shown in FIG. 15, the circumferential width of the inner side surfaces 461 and 462 of the recess 46 increases radially outward. That is, the circumferential distance between the pair of inner side surfaces 461 and 462 of at least one recessed portion 46 increases radially outward. In addition, the circumferential width of the outer side surfaces 551 and 552 of the snap-fit portion 55 also increases radially outward, similarly to the inner side surfaces 461 and 462 .

Even when such a configuration is used, the same effects as when using the recessed portion 42 and the snap fit portion 50 can be obtained.

Although the embodiments of the present invention have been described above, various modifications of the embodiments are possible within the scope of the present invention.

INDUSTRIAL APPLICABILITY The blower device of the present invention can be used as a blower device or the like for cooling electric equipment.

A blower device 10 frame 101 first frame portion 102 second frame portion 103 lead wire arrangement portion 11 frame main body 111 mounting hole 12 wind tunnel portion 121 air intake port 122 exhaust port 13 stationary blade 20 motor 21 shaft 211 bearing 22 bearing housing 221 bearing holding Part 23 Casing 23L Limit line 230 Opening 231 Cylindrical part 232 Lid part 233 Bearing housing mounting boss 24 Stator 241 Stator core 242 Insulator 243 Coil 244 Core back part 245 Teeth part 246 Insulator cylinder part 247 Lead wire 248 Drawer part 25 Rotor 251 Rotor cover 252 Magnet 253 Rotor cylindrical portion 254 Rotor top plate portion 255 Shaft fixing boss 26 Cover portion 261 Base 262 Bush 263 Cap portion 29 Wiring portion 290 Wiring space 291 First protrusion 2911 Wiring portion top plate portion 2912 Wiring portion side wall portion 292 Second protrusion Part 30 Impeller 31 Impeller Hub 311 Cover Part 312 Impeller Cylinder Part 32 Blade 40 Circuit Board 400 Through Hole 41 Electronic Part 42 Recess 42a First Recess 421 Inward Surface 422 First Inner Side 423 Second Inner Side 42b Second Recess 424 Inward Surface 425 Third inner side surface 426 Fourth inner side surface 43 Notch portion 44 Land 45 Lead wire 50 Snap fit portion 50a First snap fit portion 51 Elastic support portion 511 First outer surface 512 Second outer surface 52 Claw portion 521 Inclined surface 522 Contact Surface 50b Second snap-fit portion 53 Elastic support portion 531 Third outer surface 532 Fourth outer surface 54 Claw portion 541 Inclined surface 542 Contact surface 60 Resin portion Ct Container Cx Central axis Dp Decompression area Rd Rotation direction Sd Reference line

Claims (7)

a stator core centered on a vertically extending central axis;
an insulator covering at least a portion of the stator core;
a coil formed by winding a conductive wire around the insulator;
a circuit board disposed on one axial side of the stator core and electrically connected to the coil;
The circuit board is
a through hole formed in the center when viewed from the axial direction;
a plurality of recesses that are recessed radially outward from the edge of the through hole,
The insulator has a snap-fit portion that extends axially toward the circuit board and fits in the recess of the circuit board,
The recess has a pair of inner side surfaces facing each other in the circumferential direction,
A circumferential interval between the pair of inner side surfaces becomes narrower toward one side in the radial direction,
The snap-fit portion has outer surfaces arranged at both ends in the circumferential direction,
The motor, wherein the outer surface has an inclination that contacts with at least one surface of the inner surface of the recess. The insulator has two snap-fit portions,
2. The motor according to claim 1, wherein said circuit board has two said recesses. 3. The motor according to claim 1, wherein at least one of said recesses has a different shape from said other recesses when viewed from above in the axial direction. A pair of inner side surfaces of at least one of the recesses are arranged line-symmetrically with respect to a reference line extending in a radial direction passing through the center of the through hole and the center of the recess in the circumferential direction. A motor according to any one of 5. The motor according to any one of claims 1 to 4 , wherein the circumferential distance between the pair of inner side surfaces of at least one of the recessed portions narrows in the circumferential direction toward the radially outer side. 6. The motor according to any one of claims 1 to 5 , wherein the circumferential distance between the pair of inner side surfaces of at least one of the recesses increases in the circumferential direction toward the radially outer side. a motor according to any one of claims 1 to 6 ;
and an impeller attached to the motor.

Images