CN110661350B - Motor - Google Patents

Abstract

Provided is a motor including a rotor having a shaft extending along a central axis, a stator facing the rotor in a radial direction, a bearing rotatably supporting the shaft, an insulating member covering a part of the stator, and a lower portion of the stator in the axial direction The circuit board is arranged with a gap, the stator includes a stator core including an annular iron core back and a plurality of teeth, and a coil formed of a wire, and the insulating member includes: an iron core back covering part, which covers the iron core back; and a convex portion extending radially outward from the core back cover portion, the convex portion having a mounting portion that is positioned radially outward from the outer edge of the circuit board when viewed in the axial direction and is fixed on external devices.

Description

motor

technical field

The present invention relates to motors.

Background technique

In a conventional motor, a portion for attachment to an external device is provided on the outer periphery of the stator iron core or a casing covering the stator iron core. For example, in the stator for a rotating electrical machine described in Patent Document 1, three tab-shaped mounting portions protruding radially outward are formed at one end in the axial direction of the stator core, and these mounting portions include through holes for bolting the cover member. hole.

Patent Document 1: Japanese Patent Application Laid-Open No. 2010-136571

However, when the stator core itself is provided with the mounting portion, the shape of the stator core becomes complicated, and high technology is required for manufacture. Furthermore, by providing the mounting portion, the weight of the stator core increases.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a motor with a simple structure and a light weight.

An exemplary motor of the present invention includes a rotor, a stator, a bearing, an insulating member, and a circuit board. The rotor has a shaft extending along a central axis extending up and down. The stator is radially opposed to the rotor. Further, the stator includes a stator core including an annular core back and a plurality of teeth extending radially inward from a radially inner peripheral portion of the core back, and a coil formed of a wire, The ends of the wires are connected to the circuit board. The bearing rotatably supports the shaft. The insulating member covers a portion of the stator. Furthermore, the insulating member includes: a core back cover part covering the core back part; and a convex part extending radially outward from the core back cover part. The convex portion includes a mounting portion that is positioned radially outward from the outer edge of the circuit board when viewed in the axial direction, and that is fixed to the external device.

According to the motor of the exemplary invention, it is possible to provide a motor having a simple structure and a light weight.

Description of drawings

FIG. 1 is a perspective view of the motor of the present embodiment.

FIG. 2 is a perspective view of the motor shown in FIG. 1 viewed from the lower side.

FIG. 3 is a cross-sectional view taken along a plane including the central axis of the motor shown in FIG. 1 .

FIG. 4 is an exploded perspective view of the motor shown in FIG. 1 .

5 is a cross-sectional perspective view of a stator core and an insulating member.

FIG. 6 is a perspective view of the stator and the insulating member.

FIG. 7 is a bottom view of the stator and insulating member shown in FIG. 6 .

FIG. 8 is a bottom view of another example of the stator and the insulating member.

Fig. 9 is a bottom view of the motor.

FIG. 10 is an enlarged perspective view of the convex portion.

Fig. 11 is an enlarged view of the leg portion and the extension portion.

12 is a schematic cross-sectional view of an air blower as an external device using the motor of the present embodiment.

Label description

1: rotor; 2: stator; 3: insulating part; 4: upper plate; 5: circuit board; 6: impeller; 7: wind tunnel part; 11: shaft; 12: rotor housing; 13: molding part; 14: rotor magnet; 21: stator core; 22: coil; 31: core back cover; 32: tooth cover; 33: holding part; 34: convex part; 35: mounting part; 36: leg part; 37 : extension part; 38: guide part; 41: beam part; 42: upper bearing holding part; 43: strut part; 50: through hole; 51: circuit board recess; 61: impeller cup; 62: vane; Gas side opening; 70X: Exhaust side opening; 71: Fixing protrusion; 211: Iron core back; 212: Teeth; 331: Tube part; 332: Connection part; 340: Top surface; 351: Mounting through hole; 353: groove part; 354: notch; 361: substrate fixing part; 362: inclined part; 363: contact part; 371: first extension part; 372: second extension part; 373: first concave part; Two recesses; 381: inclined surface; 421: upper shaft through hole; 431: first plate; 432: second plate; 433: plate through hole; 501: recess; 2111: radial outer surface; 2121: flange ;2122: Radial inner surface; 333: Bottom; 334: Protrusion; 335: Rib; 3321: First link; 3322: Second link; A: Motor; Bb: Pin; Br1: Lower bearing; Br2 : Upper side bearing; Bt: Fastener; Br1: Lower side bearing; Br2: Upper side bearing; C: Center axis; F: External equipment; GL: Ground wire.

Detailed ways

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification, in the motor A, the direction parallel to the central axis C of the motor A is referred to as the "axial direction", the direction perpendicular to the central axis C of the motor A is referred to as the "radial direction", and the The direction along the circular arc centered on the central axis C of the motor A is referred to as the "circumferential direction". In addition, in this specification, in the motor A, an axial direction is an up-down direction, and "up-down" is defined based on the up-down in FIG. 3 . In addition, "up" and "down" are directions defined for ease of description, and do not limit the actual installation state of the motor A. Moreover, the case where the upper and lower sides of the acting direction of gravity do not coincide with each other is also included.

<1. Overall structure of the motor>

FIG. 1 is a perspective view of a motor according to an embodiment. FIG. 2 is a perspective view of the motor shown in FIG. 1 viewed from the lower side. FIG. 3 is a cross-sectional view taken along a plane including the central axis of the motor shown in FIG. 1 . FIG. 4 is an exploded perspective view of the motor shown in FIG. 1 . 5 is a cross-sectional perspective view of a stator core and an insulating member. FIG. 6 is a perspective view of the stator and the insulating member. FIG. 7 is a bottom view of the stator and insulating member shown in FIG. 6 . FIG. 8 is a bottom view of another example of the stator and the insulating member. Fig. 9 is a bottom view of the motor. FIG. 10 is an enlarged perspective view of the convex portion. Fig. 11 is an enlarged view of the leg portion and the extension portion. 12 is a schematic cross-sectional view of an air blower as an external device using the motor of the present embodiment.

As shown in FIGS. 1 to 4 , the motor A includes a rotor 1 , a stator 2 , an insulating member 3 , an upper plate 4 , and a circuit board 5 . A part of the stator 2 is covered with the insulating member 3 . A circuit board 5 is provided axially below the stator 2 . The rotor 1 is rotated by supplying electric power from the circuit board 5 to a coil 22 provided in the stator 2 to be described later. In the motor A, the rotor 1 is arranged radially inside the stator 2 . That is, the motor A is an inner rotor type motor. The motor A includes a rotor 1 , a stator 2 , a bearing Br1 , an insulating member 3 , and a circuit board 5 . Hereinafter, each part of the motor A will be described in detail.

<1.1 About rotor 1>

As shown in FIGS. 3 and 4 , the rotor 1 includes a shaft 11 , a rotor case 12 , a mold portion 13 , and a rotor magnet 14 . The rotor 1 has a shaft 11 extending along a central axis extending up and down. The shaft 11 has a cylindrical shape extending along the central axis. The rotor case 12 is a cylindrical body extending in the axial direction along the central axis C. And the shaft 11 penetrates the center of the rotor case 12 (refer FIG. 3).

The mold portion 13 is a molded body of resin. The molded part 13 is provided between the shaft 11 and the rotor housing 12 . The molded part 13 fixes the shaft 11 and the rotor housing 12 . Also, the molded portion 13 maintains the radial spacing of the shaft 11 and the rotor housing 12 .

The N poles and the S poles of the rotor magnet 14 are alternately arranged in the circumferential direction. The rotor magnet 14 is cylindrical. The rotor magnet 14 is fixed to the radially outer side of the rotor case 12 . The rotor magnet 14 is a cylindrical body obtained by integrally molding a resin mixed with magnetic powder. In addition, the rotor magnet 14 is alternately magnetized with N poles and S poles. In addition, the fixing of the rotor magnet 14 to the rotor case 12 may be performed by press-fitting, bonding, or the like. Furthermore, when molding the mold portion 13 , the rotor magnet 14 may be fixed together with the rotor case 12 by the mold portion 13 . Furthermore, a single ring-shaped magnet is used as the rotor magnet 14 , but a plurality of magnets may be fixed to the outer surface of the rotor case 12 .

The shaft 11 of the rotor 1 is attached to the lower bearing Br1 held by the insulating member 3 and the upper bearing Br2 held by the upper plate 4 . Thereby, the bearings Br1 and Br2 rotatably support the shaft 11 . That is, the shaft 11 and the rotor 1 including the shaft 11 are rotatably supported with respect to the stator 2 and the insulating member 3 .

<1.2 About stator 2>

As shown in FIGS. 5 to 7 , a part of the stator 2 is covered by the insulating member 3 . The stator 2 is radially opposed to the rotor 1 . The stator 2 includes a stator core 21 and a coil 22 .

<1.2.1 About the stator core 21>

The stator core 21 may be a laminated body obtained by laminating magnetic plates in the axial direction, or may be a molded body formed by sintering powder and formed as the same member, for example. The stator core 21 includes a core back 211 and a plurality of teeth 212 . The core back 211 is annular.

The plurality of teeth 212 extend radially inward from the radially inner peripheral portion of the core back 211 . That is, the stator 2 includes a stator core 21 including an annular core back 211 and a plurality of teeth 212 extending radially inward from a radially inner peripheral portion of the core back 211 . The plurality of teeth 212 are arranged at equal intervals in the circumferential direction. The radially inner side of the teeth 212 is provided with a flange portion 2121 that expands in the circumferential direction. The radially inner surface 2122 of the flange portion 2121 has a curved surface shape centered on the central axis, and the flange portion 2121 is radially opposed to the rotor magnet 14 of the rotor 1 with a gap therebetween. Here, the stator core 21 includes four teeth 212 . That is, the stator core 21 has four slots. That is, the motor A of the present embodiment is an AC motor.

<1.2.2 About the coil 22>

The coil 22 is formed by winding a wire around the teeth 212 covered by the teeth covering portions 32 of the insulating member 3 which will be described later. That is, the tooth covering portion 32 covers the teeth 212 and is wound with a wire. The coils 22 are formed on the four teeth 212, respectively. The four coils 22 are connected to each other. That is, the coil 22 is formed by a single wire. Also, both ends of the wire forming the coil 22 are connected to the circuit board 5 . In the motor A of the present embodiment, the ends of the coils 22 are connected to the linear pins Bb arranged as rods. The pin Bb is connected to the circuit board 5 , and the end of the coil 22 is electrically connected to the circuit board 5 . That is, the coil 22 is formed of a lead wire, and the end portion of the lead wire is connected to the circuit board 5 .

<1.3 About insulating member 3>

The insulating member 3 covers a part of the stator 2 . The insulating member 3 includes a core back covering portion 31 , a tooth covering portion 32 , a holding portion 33 , and a convex portion 34 . The insulating member 3 is made of, for example, a material such as resin which has insulating properties and is easy to mold. As shown in FIG. 5 , the core back cover 31 covers the core back 211 of the stator 2 .

<1.3.1 About the core back cover part 31>

As shown in FIG. 5 and the like, the core back cover 31 covers the upper and lower parts of the core back 211 in the axial direction. Further, the core back cover portion 31 also covers the radially inner peripheral portion of the core back portion 211 between the adjacent teeth 212 . That is, the core back cover part 31 covers the upper part and the lower part in the axial direction of the core back part 211 and the inner peripheral part in the radial direction between the teeth 212 . The radially outer surface 2111 of the core back 211 is exposed to the outside of the insulating member 3 . That is, at least a part of the radially outer surface of the core back 211 is exposed to the outside of the insulating member 3 .

Accordingly, when the motor A is driven, the heat generated in the stator core 21 and the coils 22 is easily released from the radially outer surface 2111 to the outside. In addition, the details will be described later, but the motor A rotates the impeller 6 for air blowing. The air flow (air flow) generated by the rotation of the impeller 6 flows in the axial direction along the radially outer surface 2111 of the core back 211 . The radially outer surface 2111 is exposed from the insulating member 3, and the radially outer surface 2111 is cooled by the air flow. Thereby, the temperature rise of the stator 2 and the motor A as a whole is suppressed.

<1.3.2 About the tooth covering portion 32 >

The tooth covering portion 32 covers at least a portion of the tooth 212 . To describe in detail, the tooth covering portion 32 covers both ends in the axial direction and both ends in the circumferential direction of the tooth 212 . That is, the radially inner surface 2122 of the flange portion 2121 of the tooth 212 is not covered by the tooth covering portion 32 . Thus, the gap between the teeth 212 and the rotor magnet 14 can be reduced. Furthermore, the radially inner surface 2122 of the flange portion 2121 is exposed to the outside of the insulating member 3 . This increases the magnetic force acting between the teeth 212 and the rotor magnet 14 . As can be seen from the above description, the rotational efficiency of the motor A can be improved.

The tooth covering portion 32 is a molded body formed from the same member as the core back covering portion 31 . Thereby, the number of parts can be suppressed.

<1.3.3 About the holding part 33>

The holding portion 33 extends along the central axis from the lower end portion in the axial direction of the core back cover portion 31 . The holding portion 33 holds the lower bearing Br1.

The holding portion 33 includes a cylindrical portion 331 and a connecting portion 332 . The cylindrical portion 331 has a cylindrical shape extending parallel to the central axis. As shown in FIG. 3 and the like, the radially inner surface of the cylindrical portion 331 holds the radially outer surface of the outer ring of the lower bearing Br1 . The lower bearing Br1 is a ball bearing, and balls are arranged between the outer ring and the inner ring.

The outer ring is held by the cylindrical portion 331 , and the lower bearing Br1 is fixed to the holding portion 33 . Thus, the center of the lower bearing Br1 and the center axis C overlap. Further, the shaft 11 is fixed to the inner ring of the lower bearing Br1. Thereby, the shaft 11 is rotatably supported by the lower bearing Br1.

The outer ring of the lower bearing Br1 is fixed by being press-fitted into the cylindrical portion 331, for example. But it is not limited to this. The outer ring of the lower bearing Br1 may be fixed to the cylindrical portion 331 by welding, bonding, or the like, and a method capable of accurately overlapping the center of the lower bearing Br1 and the central axis C for fixing can be widely used. In addition, in this embodiment, although a ball bearing is used as the lower bearing Br1, it is not limited to this. Bearings of a structure capable of rotatably supporting the shaft 11 can be widely used.

The cylindrical portion 331 includes a bottom portion 333 and a protruding portion 334 . The bottom portion 333 extends toward the central axis C from the lower end portion in the axial direction of the cylindrical portion 331 . The bottom portion 333 is in the shape of a flat plate perpendicular to the center axis C. As shown in FIG. The protruding portion 334 protrudes axially downward from the lower surface of the bottom portion 333 . As shown in FIG. 2 , FIG. 3 , and the like, the protruding portion 334 has a cylindrical shape, and the center thereof overlaps with the center axis C. As shown in FIG. That is, the protruding portion 334 extends axially downward from the center portion in the radial direction of the bottom portion 333 . In addition, the details will be described later, and by doing so, the radial positioning of the circuit board 5 can be performed.

Further, the protruding portion 334 is provided with a rib 335 extending in the axial direction on the radially outer surface. The details will be described later, and by doing so, positioning in the circumferential direction of the circuit board can be performed.

The connection portion 332 connects the core back covering portion 31 and the cylindrical portion 331 . As shown in FIG. 7 , in the insulating member 3 , there are four connecting portions 332 that connect the core back covering portion 31 and the cylindrical portion 331 . By arranging the connecting portions 332 at equal intervals, vibration, shaking, and the like of the shaft 11 can be suppressed. Therefore, the rotation accuracy of the motor A can be improved. Furthermore, in the present embodiment, the holding portion 33 has a configuration in which the connecting portion 332 having a thin plate shape when viewed in the axial direction is arranged, but the present invention is not limited to this. For example, it may be an annular shape covering the lower part in the axial direction of the stator 2 .

In this embodiment, the number of the connection parts 332 is the same as the number of the teeth 212 . If the number of the connection parts 332 is the same as the number of the teeth 212 , the insulating member 3 can be prevented from becoming complicated, and the cylindrical part 331 can be firmly fixed by the connection parts 332 .

The connection portion 332 includes a first connection portion 3321 and a second connection portion 3322 . The first connection portion 3321 extends in the axial direction from the lower end portion in the axial direction of the core back cladding portion 31 . The second connection portion 3322 extends radially inward from the lower end portion in the axial direction of the first connection portion 3321 .

Since the connecting portion 332 includes the first connecting portion 3321, the cylindrical portion 331 can be disposed away from the axially downward direction. As a result, the axial lengths of the lower bearing Br1 and the upper bearing Br2 can be increased, and the rotation accuracy of the shaft 11 can be improved. Furthermore, the distance between the circuit board 5 and the stator 2 can be increased. Thereby, the circuit board 5 and the electronic components mounted on the circuit board 5 are less likely to be affected by the heat of the stator 2 . Also, spaces are provided around the teeth 212 . Therefore, the heat of the stator 2 can be dissipated from the space to the outside.

The first connection portion 3321 and the second connection portion 3322, that is, the connection portion 332, are arranged between the teeth 212 adjacent to each other in the circumferential direction when viewed in the axial direction. Thereby, when the wire is wound around the teeth 212, a jig, a mechanical device, or the like can be inserted. That is, it is easy to secure a space for winding the coil. Therefore, the formation of the coil 22 becomes easy. Furthermore, among the respective portions of the insulating member 3, there is no portion overlapping in the axial direction when viewed in the axial direction. Therefore, the insulating member 3 can be molded by the mold pulled out in the axial direction upward and the mold pulled out in the axial direction downward. Thereby, the mold can be simplified, and the labor and time required for the manufacture of the insulating member 3 can be reduced.

Furthermore, as shown in FIG. 7 etc., the 2nd connection part 3322 connects the axial direction lower end part of the 1st connection part 3321 and the cylindrical part 331. The first connecting portion 3321 and the second connecting portion 3322 have the same width in the circumferential direction. Moreover, the width|variety in the circumferential direction of the 1st connection part 3321 and the 2nd connection part 3322 is smaller than the space|interval of the flange part 2121 of the tooth 212 adjacent in the circumferential direction. By making the width of the connecting portion 332 narrow, the circumferential length of the insulating member covering the radially inner end portion of the teeth 212 extending in the circumferential direction can be made long. Thereby, more wires can be wound around the teeth 212 . Therefore, the degradation of the characteristics of the motor A can be suppressed.

<1.3.4 About the convex part 34>

As shown in FIG. 5 , FIG. 7 , and the like, the plurality of protrusions 34 extend radially outward from the core back cover 31 . That is, the insulating member 3 includes the core back covering portion 31 which covers the core back portion 211 , and the convex portion 34 which extends radially outward from the core back covering portion 311 . The convex portion 34 has a portion located radially outward of the outer edge of the circuit board 5 when viewed in the axial direction. The convex portion 34 includes a mounting portion 35 . In the present embodiment, the insulating member 3 includes a pair of convex portions 34 . Moreover, a pair of convex parts 34 are axially symmetrical with respect to the center axis line C. As shown in FIG.

<1.3.5 About the mounting part 35>

The attachment portion 35 is provided at a radially outer portion of the convex portion 34 from the outer edge of the circuit board 5 . The attachment portion 35 is fixed to an external device F to be described later. That is, the convex part 34 is provided with the attachment part 35 which is positioned radially outward from the outer edge of the circuit board 5 when viewed in the axial direction, and is fixed to the external device F. As shown in FIG.

As shown in FIG. 12 , the fixing member is, for example, a screw Sc. Moreover, the attachment part 35 is provided with the attachment through-hole 351 through which the screw Sc penetrates. That is, the attachment portion 35 includes an attachment through hole 351 penetrating in the axial direction. Thereby, since the attachment part 35 is provided with the attachment through-hole 351, it can be positioned with respect to the external device F, and the fixing to the external device by screwing or the like becomes easy. Furthermore, as shown in FIGS. 3 , 7 , and the like, the upper surface of the convex portion 34 includes a hole portion 352 having a larger diameter than the mounting through hole 351 when viewed in the axial direction. Furthermore, the attachment portion 35 includes a groove portion 353 extending from the radially outer surface of the convex portion 34 toward the hole portion 352 .

Furthermore, as shown in FIG. 8 , the attachment portion 35 may include a notch 354 recessed from the radially outer edge portion to the radially inner side. In addition, the direction in which the notch 354 is recessed is not limited to the radial inner side, and may be, for example, the circumferential direction. That is, the attachment part 35 is provided with the notch 354 recessed in the direction perpendicular|vertical to the axial direction. When the mounting portion 35 is provided with the notch 354, it is possible to perform fine adjustment in the radial direction and/or the circumferential direction when the mounting portion 35 is mounted on the external device F. As shown in FIG.

<1.3.6 About the leg portion 36 and the extension portion 37 >

As shown in FIG. 10, the convex part 34 is provided with the extension part 37 and the leg part 36 which protrudes in the axial direction from the axial direction lower end part. The leg portion 36 protrudes axially downward from the lower end portion in the axial direction of the convex portion 34 . Moreover, the axial lower end part of the leg part 36 is provided with the board|substrate fixing|fixed part 361. The extension portion 37 extends axially downward toward the circuit board 5 from the lower end portion in the axial direction of the convex portion 34 .

The leg portion 36 has a flat plate shape extending parallel to the axial direction, and can be elastically deformed. The circumferential width of the leg portion 36 is narrower than the radial width. That is, the leg portion 36 can be elastically deformed in the circumferential direction. Further, the board fixing portion 361 is arranged at the lower end portion in the axial direction of the leg portion 36 . However, the arrangement direction of the leg portion 36 is not limited to the direction shown in FIG. 7 .

As shown in FIG. 9 , FIG. 10 , etc., the board fixing portion 361 protrudes from the lower end portion in the axial direction of the leg portion 36 in a direction intersecting with the axial direction, that is, in the circumferential direction. The board fixing portion 361 protrudes in the direction in which the leg portion 36 is elastically deformed. Further, the substrate fixing portion 361 includes an inclined portion 362 and a contact portion 363 . The contact portion 363 is in contact with the axially lower surface of the circuit board 5 . Thereby, the insulating member 3 has three functions of insulating the stator core 21 and the coil 22 , holding the bearing Br1 , and fixing the circuit board 5 . Therefore, there is no need to provide other parts dedicated to each function, and the number of parts can be suppressed.

The inclined portion 362 has an inclined surface that expands in the circumferential direction as it goes upward from the lower part in the axial direction. The contact portion 363 is arranged at the upper end portion in the axial direction of the inclined portion 362 . The contact portion 363 has a plane perpendicular to the center axis C, for example. The leg portion 36 penetrates through a circuit board recess 51 , which will be described later, provided in the circuit board 5 . Furthermore, the contact portion 363 of the board fixing portion 361 is in contact with the edge portion of the circuit board recess 51 . Thereby, the insulating member 3 and the circuit board 5 are fixed. That is, the convex portion 34 includes the leg portion 36 that protrudes axially downward and includes a board fixing portion 361 that is in contact with the axial lower surface of the circuit board 5 , and an extension portion 37 that extends axially downward toward the circuit board . In addition, the details of the fixing of the insulating member 3 and the circuit board 5 will be described later. When the circuit board 5 is attached to the motor A through the board fixing portion 361 , the circuit board 5 comes into contact with the extension portion 37 . Therefore, the circuit board 5 is positioned in the axial direction. Furthermore, the load applied to the board fixing portion 361 can be reduced. Thereby, the workability|operativity of the assembly of the motor A improves.

The extension portion 37 includes a first extension portion 371 and a second extension portion 372 . The first extension portion 371 is adjacent to the leg portion 36 in the circumferential direction. Also, the second extension portion 372 is radially adjacent to the leg portion 36 . By arranging the leg portions 36 adjacent to the extension portions 37 , when the circuit board 5 and the insulating member 3 are fixed, the load (stress) concentrated on the leg portions 36 is received by the extension portions 37 . Therefore, the inclination of the circuit board 5 due to the load can be suppressed. The lower end surface of the first extension portion 371 and the lower end surface of the second extension portion 372 are in contact with the upper surface of the circuit board 5 . In addition, the lower end surface of the first extension portion 371 and the lower end surface of the second extension portion 372 may not be in contact with the circuit board 5 , and a gap may be formed between the lower end surface and the circuit board 5 . Since the convex portion 34 includes the two extending portions 371 and 372 , the circumferential and radial loads applied to the substrate fixing portion 361 can be reduced. Thereby, the effect of holding the circuit board 5 by the board fixing portion 361 is enhanced.

When the lower end surface of the extension portion 37 is in contact with the upper surface of the circuit board 5 , when the circuit board 5 is fixed to the insulating member 3 , the circuit board 5 is pressed by the extension portion 37 in the axial direction. Therefore, the insulating member 3 and the circuit board 5 can be fixed with high precision. Furthermore, when a gap is formed, the circuit board 5 is also deformed when the circuit board 5 and the insulating member 3 are fixed, and the circuit board 5 is positioned in the axial direction by contacting the lower end surface of the extension portion 37 . Thereby, the workability|operativity of the assembly of the motor A improves. That is, when the lower end surface of the extension portion 37 is in contact with the upper surface of the circuit board 5 or opposed to each other with a gap therebetween, the assembly accuracy and workability of the motor A are improved.

The first extending portion 371 is adjacent to the lower end portion in the axial direction of the leg portion 36 via a first recessed portion 373 recessed in the axial direction (see FIG. 10 ). The second extending portion 372 is adjacent to the leg portion 36 via a second recessed portion 374 recessed in the axial direction (see FIG. 10 ). That is, the leg portion 36 and the extension portion 37 are adjacent to each other via the recessed portion 373 ( 374 ) recessed toward the upper direction in the axial direction. By providing the recessed portions 373 ( 374 ), propagation of stress between the leg portions 36 and the extension portions 37 can be suppressed. Thereby, it can suppress that the function cannot be fully utilized due to the influence of the stress from other parts.

In this way, since the leg portion 36 is adjacent to the first extension portion 371 with the first concave portion 373 interposed therebetween, when the leg portion 36 is deflected, the displacement of the leg portion 36 , that is, the stress is hardly transmitted to the first extension portion 371 . Therefore, when the leg portion 36 is elastically deformed, the first extension portion 371 is not easily deformed. Thereby, the axial position of the lower end surface of the first extension portion 371 is less likely to be displaced, so that the positioning accuracy of the circuit board 5 in the axial direction can be improved. Also, the elastic deformation of the leg portion 36 is not easily hindered by the first extension portion 371 .

Similarly, since the leg portion 36 and the second extension portion 372 are adjacent to each other with the second concave portion 374 interposed therebetween, when the leg portion 36 is deflected, the displacement of the leg portion 36 , that is, the stress is hardly transmitted to the second extension portion 372 . Therefore, when the leg portion 36 is elastically deformed, the second extension portion 372 is not easily deformed. As a result, the axial position of the lower end surface of the second extension portion 372 is less likely to be displaced, so that the positioning accuracy in the axial direction of the circuit board 5 can be improved. Also, the elastic deformation of the leg portion 36 is less likely to be hindered by the second extension portion 372 .

As described above, the two convex portions 34 are respectively disposed at positions that are axially symmetric across the central axis C. As shown in FIG. Moreover, the leg part 36 and the extension part 37 with which each convex part 34 is equipped are also axially symmetrical with respect to the center axis line C. As shown in FIG. That is, the plurality of extension portions 37 and the plurality of leg portions 36 are arranged at positions symmetrical with respect to the central axis C. As shown in FIG. With this arrangement, the circuit board 5 can be more stably fixed by the board fixing portion 361 . Furthermore, since the circuit board 5 is fixed at a position symmetrical with respect to the central axis C, the inclination of the circuit board 5 with respect to the axis can be suppressed.

<1.3.7 About the guide part 38>

As shown in FIG. 1 , FIG. 4 , etc., the upper plate 4 is fixed to the upper surface 340 of the convex portion 34 . Further, the upper surface 340 of the convex portion 34 includes a pair of guide portions 38 arranged in the circumferential direction. That is, the convex portion 34 further includes a pair of guide portions 38 that protrude in the axial direction from the surface 340 to which the upper plate 4 is fixed and are arranged in the circumferential direction.

As shown in FIG. 10 , the pair of guide portions 38 have inclined surfaces 381 in the upper portion in the axial direction. The inclined surfaces 381 of each of the pair of guide portions 38 have inclinations that go upward and away from each other with respect to the other. In addition, the inclined surfaces 381 may be provided on both sides of the pair of guide portions 38, or may be provided on one side. That is, at least one guide portion 38 of the pair of guide portions 38 includes an inclined surface 381 having an inclination that moves away from the other guide portion 38 as it moves away from the surface 340 to which the upper plate 4 is fixed in the axial direction. Thereby, the interval in the circumferential direction of the pair of guide portions 38 is narrowed toward the axially downward direction. The first plate 431 of the upper plate 4 is positioned in the circumferential direction when the first plate 431 of the upper plate 4 comes into contact with the inclined surface 381 of the guide portion 38 and moves in the axial direction. Therefore, workability can be improved.

<1.4 About the upper board 4>

As shown in FIGS. 1 , 4 and the like, the upper plate 4 is attached to the upper surface 340 of the convex portion 34 of the insulating member 3 . That is, the convex part 34 is further provided with the upper plate 4 fixed via the fastener Bt. The upper plate 4 is made of metal. The upper plate 4 includes a beam portion 41 , an upper bearing holding portion 42 , and a pillar portion 43 . The beam portion 41 , the upper bearing holding portion 42 , and the strut portion 43 are integrally formed. However, it is not limited to this, and an assembly formed by assembling each part formed as a different member may be used.

The beam portion 41 has a plate shape that expands in the radial direction of the central axis C. As shown in FIGS. 1 and 4 , the beam portion 41 has a rectangular shape when viewed from the axial direction. The upper bearing holding portion 42 is arranged at the radial center portion of the beam portion 41 . The upper bearing holding portion 42 holds the upper bearing Br2. The upper bearing holding portion 42 has a bottomed cylindrical shape that protrudes axially upward. The upper bearing holding portion 42 is provided with an upper shaft through hole 421 through which the shaft 11 penetrates in the center of the bottom portion.

The upper bearing Br2 is a ball bearing, and balls are arranged between the outer ring and the inner ring. Then, the outer ring is fixed to the upper bearing holding portion 42 , so that the upper bearing Br2 is fixed to the upper bearing holding portion 42 . Thereby, the center of the upper bearing Br2 overlaps with the center axis C. Further, the shaft 11 is fixed to the inner ring of the upper bearing Br2. Thereby, the shaft 11 is rotatably supported by the upper bearing Br2. In addition, when the shaft 11 is rotatably supported by the upper bearing Br2 , the shaft 11 penetrates the upper shaft through hole 421 of the upper bearing holding portion 42 .

The strut portion 43 is connected to both ends in the radial direction of the beam portion 41 . The strut portion 43 includes a first plate 431 and a second plate 432 . The second plates 432 are arranged to face each other with the central axis C interposed therebetween. The first plate 431 has a flat plate shape that expands radially outward from the lower end portion in the axial direction of the second plate 432 .

The first plate 431 is fixed to the upper surface 340 of the convex portion 34 . Furthermore, the second plate 432 extends upward from the radially inner end portion of the first plate 431 . That is, the upper plate 4 includes a first plate 431 extending in the radial direction and facing the upper surface 340 of the convex portion 34 in the axial direction, and a second plate 431 extending axially upward from the radially inner end portion of the first plate 431 . plate 432.

A plate through hole 433 penetrating in the axial direction is provided in the center portion of the first plate 431 . The first plate 431 arranged on the upper surface 340 is guided by the inclined surface 381 and arranged on the upper surface 340 . Furthermore, the first plate 431 is fixed to the convex portion 34 by screws Bt serving as fasteners. That is, the 1st board 431 is arrange|positioned between a pair of guide part 38, and the 1st board 431 is fixed to the convex part 34 by the fastener Bt.

The upper plate 4 is fixed to the upper surface 340 of the convex portion 34 by passing the screw Bt through the plate through hole 433 of the first plate 431 . Thereby, the upper plate 4 is fixed to the insulating member 3 . At this time, the second plate 432 is in contact with the portion of the core back 211 exposed to the outside of the insulating member 3 , that is, the radially outer surface of the core back 211 . That is, the upper plate 4 is in contact with the core back 211 and at least a portion in contact with the core back 211 and the fastener Bt has conductivity. Further, the second plate 432 is in radial contact with the core back 211 . By bringing the fasteners Bt such as screws into contact with the upper plate 4 and the upper plate 4 in contact with the iron core back 211 , the iron core back 211 and the fastener Bt can be brought into electrical contact. Thereby, the stator core 21 can be grounded easily.

In addition, the ground wire GL is commonly fastened to one of the first plates 431 of the upper plate 4 by screws Bt. Thereby, the upper plate 4 is grounded. Also, the core back 211 that is in contact with the second plate 432 of the upper plate 4 is also grounded.

<1.4 About the circuit board 5>

The circuit board 5 is arranged on the axial lower side of the insulating member 3 . That is, the circuit board 5 and the lower part of the stator 2 are arranged with a gap in the axial direction. The circuit board 5 is electrically connected to the plurality of coils 22 . The circuit board 5 includes a drive circuit (not shown). That is, the coil 22 is formed of a lead wire, and the end portion of the lead wire is connected to the circuit board 5 . The drive circuit supplies current to the plurality of coils 22 at appropriate timing.

The circuit board 5 includes a through hole 50 and a circuit board recess 51 . The circuit board 5 has a disc shape. Furthermore, the through hole 50 is formed in the radially central portion of the circuit board 5 . The inner edge portion of the through hole 50 has a concave portion 501 recessed radially outward.

When the circuit board 5 is attached to the axial lower side of the insulating member 3 , the protruding portion 334 penetrates the through hole 50 . In addition, the protruding portion 334 may not penetrate through the through hole 50 . For example, the lower surface of the protruding portion 334 may be located between the upper surface and the lower surface of the circuit board 5 inside the through hole 50 . Further, the ribs 335 of the protruding portion 334 are arranged in the recessed portion 501 of the through hole 50 . Thereby, the circuit board 5 is positioned in the circumferential direction.

At this time, the leg portion 36 penetrates the circuit board recess 51 of the circuit board 5 . Also, the upper surface of the contact portion 363 is in contact with the lower surface of the circuit board 5 . Thereby, the axial downward movement of the circuit board 5 is restricted. At this time, the extension parts 37 (the first extension part 371 and the second extension part 372 ) are in contact with the upper surface of the circuit board 5 . The circuit board 5 is held by the board fixing portion 361 and the extension portion 37 .

<1.5 About the manufacture of motor A>

In the present embodiment, the insulating member 3 is an integrally molded body of resin, and covers the stator core 21 . Resin molding of the insulating member 3 will be described. First, the stator core 21 prepared in advance is fixed inside a mold for resin molding. Then, the molding resin is filled into the mold. At this time, the radially outer surface of the core back 211 is in contact with the mold. Therefore, the radially outer surface of the core back 211 is not covered by the insulating member 3, that is, exposed to the outside. Likewise, by bringing the radially inner surface of the flange portion 2121 of the teeth 212 into contact with the mold or the nest, the radially inner surface of the flange portion 2121 can also be exposed to the outside of the insulating member 3 .

Then, after the resin is cured, the mold is removed, whereby the insulating member 3 covers a part of the stator core 21 . As described above, when viewed from the axial direction, the connecting portion 332 is disposed between the teeth 212 adjacent to each other in the circumferential direction. Therefore, the mold is composed of a mold drawn up in the axial direction and a mold drawn out in the axial direction downward.

Then, a wire is wound around the teeth 212 covered by the teeth covering portions 32 of the insulating member 3 to form the coil 22 . At this time, the circumferential width of the connecting portion 332 is smaller than the minimum distance between the teeth 212 adjacent to each other in the circumferential direction. Thereby, when the wire is wound around the teeth 212, a jig, a mechanical device, or the like can be inserted. That is, it is easy to secure a space for winding the coil. Therefore, the formation of the coil 22 becomes easy.

Then, after covering a part of the stator core 21 with the insulating member 3 , the lower bearing Br1 is fixed to the cylindrical portion 331 . In addition, it does not specifically limit as a fixing method, Here it is performed by press-fitting. Then, the upper bearing Br2 is fixed to the upper bearing holding portion 42 of the upper plate 4 . In addition, the fixing method is the same press-fitting as the lower bearing Br1. Then, the shaft 11 of the rotor 1 is held by the lower bearing Br1. Furthermore, the shaft 11 is held by the upper bearing Br2 held by the upper plate 4 . Then, the first plate 431 of the pillar portion 43 of the upper plate 4 is arranged on the upper surface 340 of the convex portion 34, and fixed with screws Bt as fasteners. At this time, the ground wire GL is fastened together to one screw Bt. Thereby, the rotor 1 is rotatably supported by the stator 2 .

Furthermore, the circuit board 5 is mounted in the axial direction from below the stator 2 on which the rotor 1 is supported. At this time, by inserting the protrusions 334 into the through holes 50 of the circuit board 5, the circuit board 5 is positioned in the radial direction. At the same time, by inserting the ribs 335 formed on the protrusions 334 into the recesses 501, the circuit board 5 is positioned in the circumferential direction. Thereby, the circuit board recessed part 51 of the circuit board 5 overlaps with the leg part 36 in the axial direction. On the other hand, the board fixing portion 361 of the leg portion 36 overlaps with the edge portion of the circuit board recess 51 in the axial direction.

In this state, by moving the circuit board 5 upward in the axial direction, the inclined portion 362 of the board fixing portion 361 is pressed by the edge portion of the circuit board concave portion 51 . Also, the legs 36 are elastically deformed by the force. Then, when the board fixing portion 361 is positioned below the lower surface of the circuit board 5 , the inclined portion 362 is released from the edge portion of the circuit board recess 51 , and the elastically deformed leg portion 36 returns to its original shape. Furthermore, the contact portion 363 of the board fixing portion 361 is in contact with the lower surface of the circuit board 5 . Thereby, the axial downward movement of the circuit board 5 is restricted. Also, the circuit board 5 is in contact with the lower surface of the extension portion 37 . This prevents the circuit board 5 from being too close to the stator 2 and maintains the position of the circuit board 5 in the axial direction, thereby suppressing inclination with respect to the axis.

In the motor A shown above, the insulating member 3 covering a part of the stator core 21 and the holding portion 33 holding the lower bearing Br1 are formed as an integrally formed body. As a result, fixing tools such as screws for fixing the insulating member 3 and the holding portion 33 can be omitted, and the number of components can be reduced. Furthermore, since the screw fixing work is not required, the man-hours for work can also be reduced. Furthermore, compared with the case where the holding portion is formed of a metal plate such as a metal plate, the weight of the holding portion can be reduced. Thereby, the weight of the motor A can be reduced.

By holding the lower bearing Br1 by the cylindrical portion 331 of the holding portion 33, the center lines of the stator 2 and the lower bearing Br1 are both aligned, and can be aligned with the center axis C here. That is, in the attachment of the lower bearing Br1, the alignment of the stator 2 and the lower bearing Br1, that is, the so-called centering operation can be omitted, and the man-hours required for manufacturing can be reduced.

<3. About the installation of the motor A to the external device F>

The external device F to which the motor A of the present invention is mounted will be described with reference to the drawings. 12 is a cross-sectional view showing a state in which the motor of the present invention is mounted to an external device. In addition, in the present embodiment, the external device F to which the motor A is mounted is an air blower that generates an air flow inside the wind tunnel portion 7 .

As shown in FIG. 12 , the external device F includes a motor A, an impeller 6 , and a wind tunnel portion 7 . In the external device F, the motor A is housed inside the wind tunnel portion 7 . Further, the wind tunnel portion 7 is a cylindrical body extending in the axial direction. Furthermore, the wind tunnel portion 7 includes a fixing protrusion 71 extending radially inward on the radially inner surface.

The motor A is accommodated inside the wind tunnel portion 7 . Then, in a state where the convex portion 34 and the fixing protrusion 71 overlap in the axial direction, the screw Sc is inserted into the mounting portion 35 and fixed. At this time, since the head of the screw Sc is accommodated inside the hole portion 352, the head of the screw Sc does not protrude in the axial direction. Then, by fixing the nut Nt to the portion where the screw Sc protrudes from the lower surface of the convex portion 34 axially downward, the fixing protrusion and the convex portion 34 are fixed. That is, the motor A is fixed to the inside of the wind tunnel portion 7 .

However, the fixing method of the motor A is not limited to this. For example, the screw Sc may be fixed to the nut Nt by inserting the screw Sc from below in the axial direction and arranging the nut Nt inside the hole portion 352 of the attachment portion 35 . Furthermore, the fixing may be performed by screwing the screw Sc into the fixing protrusion 71 .

Moreover, although the fixing protrusion 71 is arrange|positioned below the convex part 34 in the axial direction, it may be arrange|positioned upward. In this case, the fixing protrusions 71 may be arranged in the hole portion 352 and the groove portion 353 . With this arrangement, the motor A can be locked (positioned) during assembly. Thereby, workability|operativity can be improved.

Furthermore, the motor A in which the attachment portion 35 having the notch 354 shown in FIG. 8 is formed may be attached. With this configuration, the motor A can be moved in the direction in which the notch 354 is recessed. Thereby, the position of the motor A with respect to the wind tunnel portion 7 can be adjusted. In addition, although the convex part 34 and the fixing protrusion 71 are fixed using the screw Sc which penetrates both the convex part 34 and the fixing protrusion 71, it is not limited to this. For example, a fastener such as a rivet may be used, or a screw provided in advance to the fixing protrusion 71 may be passed through the mounting portion 35 and fixed with a nut.

The impeller 6 is fixed to the upper end of the shaft 11 . The impeller 6 includes an impeller cup 61 and a plurality of blades 62 . The impeller cup 61 has a cylindrical shape. The inside of the impeller cup 61 is provided with a cylindrical hub (not shown) extending in the axial direction. The shaft 11 is inserted into the inside of the hub to be fixed. Thereby, the impeller 6 is fixed to the shaft 11 . Furthermore, the impeller 6 is arranged inside the wind tunnel portion 7 . The impeller 6 rotates about the central axis C together with the shaft 11 . The plurality of blades 62 are inclined in the circumferential direction, respectively. The plurality of vanes 62 extend from the radially outer surface of the impeller cup 61 toward the radially outer side. The plurality of blades 62 are arranged at equal intervals in the circumferential direction.

In the external device F, when the motor A is driven, the shaft 11 is rotated. By the rotation of the shaft 11, the impeller 6 rotates around the central axis C. The rotation of the impeller 6 generates an air flow from the upper part in the axial direction to the lower part, that is, an air flow inside the wind tunnel part 7 . For further explanation, the opening at the upper end portion in the axial direction of the wind tunnel portion 7 is the intake side opening 70I, and the opening at the lower end portion is the exhaust side opening 70X. In the wind tunnel portion 7 , by the rotation of the impeller 6 , air is sucked from the intake side opening 70I, and air is discharged from the exhaust side opening 70X.

In the external device F, the inner wall surface of the wind tunnel portion 7 and the radially outer surface of the motor A are opposed to each other with a gap in the radial direction. In the external device F, the airflow flows in the gap between the inner wall surface of the wind tunnel portion 7 and the motor A in the radial direction. That is, the gap between the inner wall surface of the wind tunnel portion 7 and the radial direction of the motor A serves as an air passage. As described above, in the motor A, the radially outer surface 2111 of the core back 211 is exposed to the outside of the insulating member 3 . Therefore, when the motor A is attached to the wind tunnel portion 7 , the radially outer surface 2111 of the core back portion 211 is exposed to the inside of the air passage. The radially outer surface 2111 of the core back 211 is cooled by the air flow. As a result, the entire stator core 21 is cooled, and the coil 22 is also cooled. Therefore, in the motor A, the decrease in performance due to the temperature rise can be suppressed.

When the motor A of the present invention is mounted on an external device, the convex portion 34 protruding radially outward from the stator cladding layer covering the stator core 21 is fixed. At the time of fixing, even if a force is applied to the convex portion 34, the force hardly acts on the rotor 1, the stator 2, the circuit board 5, and the like. Therefore, it is possible to suppress the reduction of the rotation accuracy due to the strain caused by the force acting on the motor A at the time of mounting.

Further, in the motor A of the present invention, the holding portion 33 holding the lower bearing Br1 and the insulating member 3 covering a part of the stator 2 are formed by integral molding. Therefore, compared with the structure provided with the holding|maintenance part 33 as another part, assembly man-hour can be reduced, while reducing the number of parts.

The embodiments of the present invention have been described above, but the embodiments can be modified in various ways within the scope of the gist of the present invention.

Industrial Availability

The motor of the present invention can be used, for example, as a drive device for external equipment such as a dryer, a blower fan, and a vacuum cleaner.

Claims (10)

1. A motor is provided with:

a rotor having a shaft extending along a central axis, the central axis extending in an up-down direction;

a stator that is radially opposed to the rotor;

a bearing rotatably supporting the shaft;

an insulating member covering a part of the stator; and

a circuit board disposed with a gap in an axial direction from a lower portion of the stator,

the stator includes:

a stator core including an annular core back portion and a plurality of teeth extending radially inward from a radially inner peripheral portion of the core back portion; and

A coil formed of a wire, an end of the wire being connected with the circuit board,

the insulating member includes:

an iron core back coating portion that covers the iron core back; and

a convex portion extending from the core back cladding portion toward a radially outer side,

the protruding portion includes a mounting portion that is located radially outward of an outer edge of the circuit board when viewed in an axial direction and that is fixed to an external device,

the convex portion includes:

a leg portion projecting axially downward and including a substrate fixing portion contacting an axially lower surface of the circuit board; and

an extension portion extending axially downward toward the circuit board,

the lower end surface of the extension portion is in contact with the upper surface of the circuit board or is opposite to the upper surface of the circuit board with a gap,

the leg portion is adjacent to the extension portion, and both the leg portion and the extension portion extend from the same protrusion.

2. The motor of claim 1,

the mounting portion includes a through hole that penetrates in the axial direction.

3. The motor according to claim 1 or 2,

the mounting portion has a notch recessed in a direction perpendicular to the axial direction.

4. The motor of claim 1,

The leg portion is adjacent to the extending portion via a recess portion recessed upward in the axial direction.

5. The motor of claim 1,

the extension part is provided with:

a first extension circumferentially adjacent the leg; and

a second extension radially adjacent the leg.

6. The motor of claim 1,

the insulating member is provided with a plurality of the projections,

the plurality of extending portions and the plurality of leg portions are disposed at positions symmetrical with respect to the central axis.

7. The motor according to claim 1 or 2,

the convex part is further provided with an upper plate fixed by a fastener,

the upper plate is in contact with the core back and has conductivity at least in a portion in contact with the core back and the fastener.

8. The motor of claim 7,

the upper plate is provided with:

a first plate extending in a radial direction and axially opposed to an upper surface of the convex portion; and

a second plate extending axially upward from a radially inner end of the first plate,

the second plate is in radial contact with the core back.

9. The motor of claim 8,

The convex portion further includes a pair of guide portions axially protruding from a surface to which the upper plate is fixed and arranged in a circumferential direction,

at least one of the pair of guide portions has an inclined surface having a slope that is away from the other guide portion as the inclined surface is axially away from the surface to which the upper plate is fixed.

10. The motor of claim 9,

the first plate is disposed between the pair of guide portions,

the first plate is fixed to the boss by the fastener.

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