Motor and blower

Abstract

The invention provides a motor and a blower. The motor includes: a rotor capable of rotating about a central axis; a stator facing the rotor with a gap therebetween; a circuit board that overlaps the stator in the axial direction on one side of the stator in the axial direction and is electrically connected to the stator; a connection part connected to the circuit board; a resin part covering at least a part of the circuit board and at least a part of the connecting part; and a first boundary section that connects the outer surface of the resin section and the connection section. The circuit board includes: a contact portion that is in contact with the resin portion; and a first annular adhesive part that is adhered to the resin part and surrounds the connecting part in an annular shape when viewed from a direction perpendicular to the circuit board. The adhesion force between the first annular adhesive portion and the resin portion is greater than the adhesion force between the contact portion and the resin portion.

Description

Technical Field

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

[0002] There is known a motor in which at least a portion of a circuit board and at least a portion of components connected to the circuit board are covered with resin (see, for example, Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2023-18900

[0004] In the motor described above, water may penetrate from the outside of the motor into the boundary between the component connected to the circuit board and the resin. In this case, the water that reaches the circuit board from the boundary may spread on the circuit board. Summary of the Invention

[0005] In view of the above-mentioned circumstances, one object of the present invention is to provide a motor and a blower capable of suppressing the diffusion of water on a circuit board.

[0006] A motor according to one embodiment of the present invention comprises: a rotor rotatable about a central axis; a stator opposed to the rotor with a gap therebetween; a circuit substrate axially overlapping and electrically connected to the stator on one axial side of the stator; a connecting portion connected to the circuit substrate; a resin portion covering at least a portion of the circuit substrate and at least a portion of the connecting portion; and a first boundary portion connecting an outer side surface of the resin portion and the connecting portion. The circuit substrate comprises: a contact portion in contact with the resin portion; and a first annular adhesive portion adhered to the resin portion and annularly surrounding the connecting portion when viewed from a direction perpendicular to the circuit substrate. The first annular adhesive portion has a greater adhesion force to the resin portion than the contact portion.

[0007] A motor according to one embodiment of the present invention comprises: a rotor rotatable about a central axis; a stator having an insulator, the stator and the rotor being opposed with a gap therebetween; a circuit substrate having a fitting portion into which the insulator fits, the circuit substrate and the stator overlapping in the axial direction; a resin portion covering at least a portion of the circuit substrate; and a second boundary portion connecting the outer side surface of the resin portion and the fitting portion. The circuit substrate comprises: a second annular contact portion in contact with the resin portion and annularly surrounding the fitting portion when viewed from a direction perpendicular to the board surface of the circuit substrate; and a second annular adhesive portion adhered to the resin portion and annularly surrounding the fitting portion when viewed from a direction perpendicular to the board surface of the circuit substrate. The second annular adhesive portion has a greater adhesion force to the resin portion than the second annular contact portion.

[0008] A blower according to one aspect of the present invention includes: the above-described motor; and an impeller portion provided on the rotor.

[0009] According to one aspect and other aspects of the present invention, in a motor and a blower, it is possible to suppress water from spreading on the surface of a circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a cross-sectional view of a blower using a motor according to one embodiment.

[0011] Figure 2 yes Figure 1 Enlarged view of Part II.

[0012] Figure 3 yes Figure 2 Cross-sectional view along the III-III direction.

[0013] Figure 4 yes Figure 1 Enlarged view of part IV.

[0014] Figure 5 yes Figure 4 Cross-sectional view along the VV direction.

[0015] Figure 6 This is a diagram showing a portion of a motor according to Modification 1.

[0016] Figure 7 This is a diagram showing a portion of a motor according to Modification 2.

[0017] Label Description

[0018] 10: Blower; 11, 111, 211: Motor; 13: Impeller; 15: Rotor; 19: Stator; 21, 121, 221: Circuit board; 21a: Board body; 21c: Anti-etching layer; 25: Resin portion; 25a: Outer surface; 33: Coil; 35: Insulator; 37: Conductive component; 39: Solder portion; 39a: Connecting portion; 41: Pad portion; 43a: First boundary portion; 43b: Second boundary portion; 45: Contact portion; 45a: First annular contact portion; 47, 247: First annular adhesive portion; 49: Fitting portion; 51: Second annular contact portion; 53: Second annular adhesive portion; 260: Primer; J: Center axis. DETAILED DESCRIPTION

[0019] The following describes a motor and a blower according to an embodiment of the present invention with reference to the accompanying drawings. The scope of the present invention is not limited to the following embodiments and can be arbitrarily modified within the technical scope of the present invention. In the following drawings, actual structures, scales, and numbers may be varied to facilitate understanding. Liquids such as water, salt water, or other aqueous solutions may sometimes be referred to simply as "water."

[0020] The center axis J of the motor of the following embodiment is appropriately shown in each figure. The center axis J is an imaginary axis. In the following description, the direction in which the center axis J extends, that is, the axial direction of the center axis J, is referred to as "axial direction", the radial direction centered on the center axis J is referred to as "radial direction", and the circumferential direction centered on the center axis J is referred to as "circumferential direction". In each figure, a Z axis parallel to the axial direction is shown. In the following description, the side to which the arrow of the Z axis in the axial direction points (+Z side) is referred to as "upper side", and the side opposite to the side to which the arrow of the Z axis in the axial direction points (-Z side) is referred to as "lower side". In the following embodiment, the lower side is equivalent to "one axial side". In addition, the upper side and the lower side are merely names used to illustrate the configuration relationship of each part, and the actual configuration relationship may also be a configuration relationship other than the configuration relationship represented by these names.

[0021] like Figure 1 As shown, the blower 10 of this embodiment includes a motor 11, an impeller 13, and a housing 17. The housing 17 is frame-shaped, surrounding a central axis J and open on both axial sides. The motor 11 and the impeller 13 are housed radially inwardly of the housing 17. The motor 11 includes a shaft 27, a rotor 15, a stator 19, a support portion 24, a bottom wall portion 26, a circuit board 21, and a resin portion 25.

[0022] The shaft 27 extends in the axial direction around the central axis J. The shaft 27 is supported by the support portion 24 so as to be rotatable about the central axis J. The lower end portion of the shaft 27 is disposed inside a cylindrical portion 24 a described later.

[0023] The rotor 15 is fixed to the upper end of the shaft 27. The rotor 15 is rotatable about the shaft 27. The rotor 15 includes an annular wall portion 29 and a rotor magnet 28. The annular wall portion 29 is annular and surrounds the central axis J. The annular wall portion 29 is located radially outward from the stator 19 and surrounds the stator 19. The rotor magnet 28 is fixed to the radially inner surface of the annular wall portion 29. The rotor 15 is provided with an impeller portion 13. The impeller portion 13 includes a plurality of blades 13a provided on the radially outer surface of the annular wall portion 29.

[0024] The stator 19 faces the rotor 15 with a gap therebetween. The stator 19 is located radially inward of the annular wall portion 29. The stator 19 is supported on the radially outer side of the cylindrical portion 24a (described later) of the support portion 24. The stator 19 includes a stator core 31, a coil 33, and an insulator 35. The stator core 31 includes a core back 31a surrounding the cylindrical portion 24a and teeth 31b extending radially outward from the core back 31a. The radially inner side of the core back 31a is fixed to the radially outer side of the cylindrical portion 24a (described later). The coil 33 is attached to the stator core 31 via an insulator 35.

[0025] The insulator 35 includes a barrel 35a, a coil placement portion 35b, and a retaining portion 35c. The insulator 35 is made of, for example, resin. The barrel 35a is cylindrical, surrounding the central axis J. The barrel 35a protrudes downward from the core back 31a of the stator core 31. In this embodiment, the barrel 35a is roughly cylindrical, centered on the central axis J and open on both sides in the axial direction. The barrel 35a is located radially outward of the cylindrical portion 24a of the support portion 24, which will be described later.

[0026] The barrel 35a has a small diameter portion 35d. The small diameter portion 35d is the lower end portion of the barrel 35a. The outer diameter of the small diameter portion 35d is smaller than the outer diameter of the portion of the barrel 35a located above the small diameter portion 35d. A step portion 35e is provided between the outer circumferential surface of the small diameter portion 35d and the outer circumferential surface of the portion of the barrel 35a located above the small diameter portion 35d, and the step portion 35e has a step surface facing downward. The small diameter portion 35d is fitted into the through hole 21j of the circuit substrate 21 described later. In this embodiment, the inner circumferential surface of the through hole 21j is the fitting portion 49 into which the insulating member 35 is fitted. The step surface facing downward of the step portion 35e contacts the circuit substrate 21.

[0027] The coil placement portion 35b protrudes radially outward from the radially outer surface of the cylindrical portion 35a. The coil placement portion 35b is located between the coil 33 and the teeth 31b. The retaining portion 35c protrudes downward from the radially outer end of the coil placement portion 35b. The retaining portion 35c supports the upper portion of the conductive member 37, which will be described later.

[0028] The support portion 24 supports the stator 19. The support portion 24 includes a cylindrical portion 24a and a bearing 24b. The cylindrical portion 24a is cylindrical and surrounds the central axis J. In the present embodiment, the cylindrical portion 24a is roughly cylindrical, centered on the central axis J and open on both sides in the axial direction. The stator core 31 is fixed to the radially outer surface of the cylindrical portion 24a. A bearing 24b is retained inside the cylindrical portion 24a. The bearing 24b rotatably supports the shaft 27. In the present embodiment, the bearing 24b is a ball bearing. The bearing 24b is fitted and retained inside the cylindrical portion 24a. Two bearings 24b are provided at intervals in the axial direction. In addition, the bearing 24b can be a rolling bearing other than a ball bearing, or a sliding bearing, as long as it can rotatably support the shaft 27. The bottom wall portion 26 is connected to the lower end of the cylindrical portion 24a. In the present embodiment, the bottom wall portion 26 is roughly disk-shaped and extends in the radial direction.

[0029] The circuit substrate 21 is located below the stator 19. The circuit substrate 21 overlaps the stator 19 in the axial direction. The surface of the circuit substrate 21 faces the axial direction. The surface of the circuit substrate 21 is perpendicular to the axial direction. In this specification, the term "a direction perpendicular to the circuit substrate 21" refers to a direction perpendicular to the surface of the circuit substrate 21. In this embodiment, the term "a direction perpendicular to the circuit substrate 21" refers to the axial direction along which the central axis J extends. The circuit substrate 21 is located axially between the stator 19 and the bottom wall portion 26.

[0030] The circuit board 21 has a through-hole 21j extending axially through the circuit board 21. In this embodiment, the through-hole 21j is a circular hole centered on the central axis J. The small-diameter portion 35d of the insulating member 35 is fitted into the through-hole 21j. The circuit board 21 is a printed wiring board having a wiring pattern.

[0031] like Figure 2 As shown, the circuit board 21 includes a substrate body 21a and a resist layer 21c. The substrate body 21a is a plate-shaped component provided with a wiring pattern. Resist layers 21c are laminated on the upper surface 21b and lower surface 21d of the substrate body 21a. The resist layers 21c are insulating films that protect the wiring patterns (not shown) provided on the upper surface 21b and lower surface 21d of the substrate body 21a. The provision of the resist layers 21c prevents solder, dirt, and the like from adhering to the surface of the substrate body 21a other than the areas to be soldered when electronic components are soldered to the wiring patterns provided on the substrate body 21a.

[0032] The coil 33 is electrically connected to the circuit substrate 21 via the conductive component 37. Thus, the circuit substrate 21 is electrically connected to the stator 19. The conductive component 37 is a metal component extending in the axial direction. In the present embodiment, the conductive component 37 is a bundling pin around which the end of the winding 33a constituting the coil 33 is wound. The conductive component 37 is held by the retaining portion 35c of the insulating member 35. The conductive component 37 protrudes downward from the retaining portion 35c. The lower portion of the conductive component 37 passes axially through the through-hole 21g provided in the circuit substrate 21. The through-hole 21g is formed by providing a plating film 21i on the inner surface of the hole portion 21h that passes through the substrate main body portion 21a in the axial direction. A pad portion 41 electrically connected to the plating film 21i of the through-hole 21g is provided on the upper surface 21b and the lower surface 21d of the substrate main body portion 21a, respectively. As Figure 3 As shown in FIG. 2 , the pad portion 41 is in an annular shape surrounding the through hole 21g on the upper surface 21b and the lower surface 21d. Figure 2 As shown, the conductive component 37 is electrically connected to the pad portion 41 and the plated film 21i via the solder portion 39. The solder portion 39 is connected to the pad portion 41 and the plated film 21i. Thus, the solder portion 39 is connected to the circuit board 21. In this embodiment, the portion of the solder portion 39 that contacts the circuit board 21 is the connecting portion 39a connected to the circuit board 21. That is, in this embodiment, the connecting portion 39a connected to the circuit board 21 includes the portion of the solder portion 39 that is connected to the circuit board 21, which connects the circuit board 21 and the conductive component 37.

[0033] An inverter circuit for supplying current to the coil 33 of the stator 19 is provided on the circuit board 21. The inverter circuit supplies current to the coil 33 via the conductive member 37. The circuit board 21 switches the current flowing through the stator 19 through the inverter circuit.

[0034] like Figure 1 As shown, the resin portion 25 covers at least a portion of the circuit substrate 21 and at least a portion of the stator 19. In this embodiment, the resin portion 25 covers substantially the entire circuit substrate 21. Figure 4As shown, the resin portion 25 covers the first surface 21e of the circuit board 21, which faces upward, and the second surface 21f of the circuit board 21, which faces downward. The first surface 21e is the upper surface of the circuit board 21. The first surface 21e includes the upper surface of the resist layer 21c provided on the upper surface 21b of the substrate body 21a, the upper surface of the pad portion 41 provided on the upper surface 21b of the substrate body 21a, and the portion of the upper surface 21b of the substrate body 21a where the resist layer 21c is not laminated. The second surface 21f is the lower surface of the circuit board 21. The second surface 21f includes the lower surface of the resist layer 21c provided on the lower surface 21d of the substrate body 21a, the lower surface of the pad portion 41 provided on the lower surface 21d of the substrate body 21a, and the portion of the lower surface 21d of the substrate body 21a where the resist layer 21c is not laminated.

[0035] In this embodiment, the resin portion 25 covers the entire stator 19, excluding the radially inner side surface of the cylindrical portion 35a of the insulator 35, the radially inner side surface of the core back 31a, and the radially outer side surfaces of the teeth 31b. The resin portion 25 also covers at least a portion of the solder portion 39, which serves as a connecting portion. In this embodiment, the resin portion 25 covers the entire solder portion 39. The resin portion 25 is made of a resin such as a hot melt adhesive, for example. The resin portion 25 is formed, for example, by insert molding, with the stator 19 and the circuit board 21 serving as insert components.

[0036] like Figure 2As shown, the motor 11 of this embodiment has a first boundary portion 43a connecting the outer side surface 25a of the resin portion 25 and the connection portion 39a of the solder portion 39. The outer side surface 25a of the resin portion 25 refers to the surface of the resin portion 25 that is exposed to the outside. The first boundary portion 43a is a portion that can serve as a water intrusion path from the outer side surface 25a of the resin portion 25 to the connection portion between the solder portion 39 and the circuit board 21, that is, the connection portion 39a. The first boundary portion 43a of this embodiment includes a portion 43a1, a portion 43a2, a portion 43a3, and a portion 43a4. The portion 43a1 is the boundary portion between the radially outer end of the tooth 31b and the resin portion 25. The radially outer end of the portion 43a1 is connected to the radially outer side surface of the tooth 31b exposed from the resin portion 25 and the outer side surface 25a of the resin portion 25. The portion 43a2 is the boundary portion between the retaining portion 35c of the insulator 35 and the resin portion 25. Portion 43a3 is the boundary between the winding 33a of the coil 33, the conductive member 37, and the resin portion 25. Portion 43a4 is the boundary between the outer surface of the solder portion 39 connected to the circuit board 21 and the resin portion 25. For example, consider the case where water enters portion 43a1 between the radially outer surface of the tooth 31b exposed from the resin portion 25 and the outer surface 25a of the resin portion 25. In this case, the water entering portion 43a1 may flow sequentially through portions 43a2, 43a3, and 43a4, reaching the portion of the solder portion 39 connected to the circuit board 21, namely, the connection portion 39a.

[0037] like Figure 4 As shown, the motor 11 of this embodiment has a second boundary portion 43b that connects the outer side surface 25a of the resin portion 25 and the fitting portion 49. The second boundary portion 43b is a portion that can serve as an intrusion path for water from the outer side surface 25a of the resin portion 25 to the fitting portion 49. The second boundary portion 43b of this embodiment includes a portion 43b1. Portion 43b1 is the boundary portion between the lower end surface of the small diameter portion 35d of the insulating member 35 and the resin portion 25. The radially inner end of portion 43b1 is connected to the radially inner side surface of the small diameter portion 35d exposed from the resin portion 25 and the outer side surface 25a of the resin portion 25. The radially outer end of portion 43b1 is connected to the inner circumferential surface of the through hole 21j of the circuit substrate 21. For example, consider the case where water enters portion 43b1 from between the radially inner side surface of the small diameter portion 35d exposed from the resin portion 25 and the outer side surface 25a of the resin portion 25. In this case, the water flowing in the portion 43 b 1 can reach the inner peripheral surface of the through-hole 21 j , that is, the fitting portion 49 .

[0038] When water reaches the connecting portion 39a via the first boundary portion 43a, it moves from the connecting portion 39a onto the circuit board 21, potentially spreading onto the circuit board 21. Furthermore, when water reaches the fitting portion 49 via the second boundary portion 43b, it could spread from the fitting portion 49 onto the circuit board 21. In this embodiment, the motor 11 is provided with a structure for preventing water that has infiltrated the first boundary portion 43a and the second boundary portion 43b from spreading onto the circuit board 21. This structure will be described below.

[0039] First, the structure for water entering the first boundary portion 43a will be described. Figure 2 As shown, the circuit board 21 has a contact portion 45 that contacts the resin portion 25 and a first annular adhesive portion 47 that is bonded to the resin portion 25. The contact portion 45 is a portion formed by the first surface 21e of the circuit board 21 and the surface of the resist layer 21c in the second surface 21f. The contact portion 45 has a first annular contact portion 45a. Figure 3 As shown, when viewed from an axial direction perpendicular to the circuit board 21, the first annular contact portion 45a has an annular shape surrounding the solder portion 39. In this embodiment, the first annular contact portion 45a has an annular shape. The first annular contact portion 45a is arranged adjacent to the outer side of the pad portion 41. When viewed from the axial direction, the first annular contact portion 45a surrounds the pad portion 41. In this embodiment, the first annular contact portion 45a has an annular shape coaxially arranged with the pad portion 41.

[0040] The first annular adhesive portion 47 is a portion of the first surface 21e of the circuit substrate 21. When viewed from an axial direction perpendicular to the circuit substrate 21, the first annular adhesive portion 47 is in an annular shape surrounding the connecting portion 39a of the solder portion 39. In the present embodiment, the first annular adhesive portion 47 is in an annular shape. The first annular adhesive portion 47 is located outside the pad portion 41 and the first annular contact portion 45a. The first annular adhesive portion 47 is arranged adjacent to the outside of the first annular contact portion 45a. When viewed from an axial direction, the first annular adhesive portion 47 surrounds the pad portion 41 and the first annular contact portion 45a. In the present embodiment, the first annular adhesive portion 47 is in an annular shape coaxially arranged with the pad portion 41 and the first annular contact portion 45a. As Figure 2 As shown, in this embodiment, the first annular adhesive portion 47 is formed by the surface of the substrate main body 21a. The first annular adhesive portion 47 is formed by providing a portion on the upper surface 21b of the substrate main body 21a where the resist layer 21c is not laminated.

[0041] Here, the resist layer 21c constituting the contact portion 45 is a layer that prevents solder, dirt, and the like from adhering to the surface of the substrate main body 21a. Therefore, it is difficult for the contact portion 45 to achieve sufficient adhesion to the resin portion 25. Consequently, a gap large enough to allow water to diffuse may form between the contact portion 45 and the resin portion 25 due to capillary action. Consequently, conventionally, when water reaches the connecting portion 39a via the first boundary portion 43a, the water that has migrated from the connecting portion 39a to the circuit substrate 21 may pass through the gap between the contact portion 45 and the resin portion 25 and diffuse onto the circuit substrate 21.

[0042] In contrast, according to the present embodiment, the adhesion between the first annular adhesive portion 47, which annularly surrounds the connecting portion 39a when viewed from the axial direction, and the resin portion 25 is greater than the adhesion between the contact portion 45 and the resin portion 25. Therefore, it is possible to suppress water from passing between the first annular adhesive portion 47 and the resin portion 25. As a result, it is possible to suppress water that has moved from the connecting portion 39a to the circuit substrate 21 from diffusing outward from the first annular adhesive portion 47. Therefore, it is possible to suppress water from diffusing on the circuit substrate 21. In addition, the adhesion between the circuit substrate 21 and the resin portion 25 can be measured, for example, as the breaking stress measured using the tensile shear bond strength test method for adhesives and rigid adherends described in JIS K6850:1999.

[0043] In this embodiment, the contact portion 45 is formed by the surface of the resist layer 21c, and the first annular adhesive portion 47 is formed by the surface of the substrate main body 21a. The surface of the substrate main body 21a not provided with the resist layer 21c tends to have greater adhesion to the resin portion 25 than the surface provided with the resist layer 21c. This makes it easier to make the adhesion between the first annular adhesive portion 47 and the resin portion 25 greater than the adhesion between the contact portion 45 and the resin portion 25. Therefore, the first annular adhesive portion 47 can be easily manufactured without using other materials, etc., by not laminating the resist layer 21c on a portion of the surface of the substrate main body 21a, or by removing a portion of the resist layer 21c laminated on the surface of the substrate main body 21a.

[0044] In this embodiment, the connection portion 39a connected to the circuit board 21 is the portion of the solder portion 39 that is connected to the circuit board 21. Therefore, the first annular adhesive portion 47 can prevent water that has penetrated between the surface of the solder portion 39 and the resin portion 25 from spreading on the circuit board 21.

[0045] like Figure 3As shown, in this embodiment, when viewed from an axial direction perpendicular to the circuit substrate 21, the width of the first annular adhesive portion 47 is greater than the width of the pad portion 41. Therefore, the width of the first annular adhesive portion 47 can be increased, making it more difficult for water to pass between the first annular adhesive portion 47 and the resin portion 25. This further suppresses water from spreading outward from the first annular adhesive portion 47. The width of the first annular adhesive portion 47 refers to the dimension between the inner and outer edges of the first annular adhesive portion 47 when viewed from the axial direction. The width of the pad portion 41 refers to the dimension between the inner and outer edges of the pad portion 41 when viewed from the axial direction.

[0046] In this embodiment, the contact portion 45 includes a first annular contact portion 45a that surrounds the solder portion 39 when viewed axially. The first annular contact portion 45a is formed from a surface of the resist layer 21c provided on the circuit board 21. When viewed perpendicular to the circuit board 21, the first annular adhesive portion 47 surrounds the first annular contact portion 45a. Thus, the resist layer 21c is provided around the areas of the circuit board 21 where the solder portion 39 is provided, such as the pad portion 41. Therefore, during soldering, the resist layer 21c forming the first annular contact portion 45a prevents solder from adhering to the substrate main body 21a and the like. Furthermore, since the first annular contact portion 45a is surrounded by the first annular adhesive portion 47 when viewed axially, even if water intrudes between the first annular contact portion 45a and the resin portion 25, the water is prevented from spreading outward beyond the first annular adhesive portion 47.

[0047] Next, the structure for water intruding into the second boundary portion 43b will be described. Figure 4 As shown, the circuit substrate 21 has a second annular contact portion 51 and a second annular adhesive portion 53. The second annular contact portion 51 is a portion that contacts the resin portion 25. The second annular contact portion 51 is a portion of the contact portion 45. That is, in this embodiment, the second annular contact portion 51 is formed by the surface of the resist layer 21c. When viewed from the axial direction, the second annular contact portion 51 surrounds the interlocking portion 49 in an annular shape. Figure 5 As shown in FIG. 1 , in this embodiment, the second annular contact portion 51 is in the shape of an annulus centered on the central axis J. Figure 4 As shown, the second annular contact portion 51 includes two second annular contact portions 51 provided on the first surface 21e of the circuit board 21 and a second annular contact portion 51 provided on the second surface 21f of the circuit board 21. When viewed axially, the two second annular contact portions 51 are arranged so as to overlap with each other. Alternatively, the two second annular contact portions 51 may be arranged so as to be offset from each other when viewed axially.

[0048] The second annular adhesive portion 53 is a portion bonded to the resin portion 25. In this embodiment, the second annular adhesive portion 53 is formed by the surface of the substrate main body portion 21a, similarly to the first annular adhesive portion 47. Figure 5 As shown in FIG. 1 , when viewed from the axial direction, the second annular bonding portion 53 surrounds the second annular contact portion 51 and the fitting portion 49 in an annular shape. Figure 4 As shown, in this embodiment, the second annular adhesive portion 53 is provided with two second annular adhesive portions 53: a second annular adhesive portion 53 provided on the first surface 21e of the circuit substrate 21, and a second annular adhesive portion 53 provided on the second surface 21f of the circuit substrate 21. When viewed from the axial direction, the two second annular adhesive portions 53 are arranged at mutually overlapping positions. The two second annular adhesive portions 53 are arranged adjacent to the radially outer side of the second annular contact portion 51 on the first surface 21e and the second surface 21f, respectively. Alternatively, the two second annular adhesive portions 53 may be arranged so as to be offset from each other when viewed from the axial direction.

[0049] The adhesion between the second annular adhesive portion 53 and the resin portion 25 is greater than the adhesion between the second annular contact portion 51 and the resin portion 25. Therefore, similar to the first annular adhesive portion 47 described above, water can be prevented from passing between the second annular adhesive portion 53 and the resin portion 25. Thus, even if water reaches the interlocking portion 49 from the second boundary portion 43b, it can be prevented from spreading outward from the second annular adhesive portion 53 on the circuit substrate 21. Furthermore, since the interlocking portion 49 connected to the second boundary portion 43b is the inner circumferential surface of the through-hole 21j of the circuit substrate 21, water that reaches the interlocking portion 49 may flow toward both the first surface 21e and the second surface 21f of the circuit substrate 21. In contrast, in this embodiment, the second annular adhesive portion 53 is provided on both the first surface 21e and the second surface 21f. Therefore, it is possible to prevent water from spreading on both the first surface 21e and the second surface 21f.

[0050] Furthermore, in this embodiment, a second annular contact portion 51 is provided inside the second annular adhesive portion 53. Therefore, the second annular contact portion 51 can be provided around the periphery of the through-hole 21j in the circuit board 21. Since the second annular contact portion 51 is formed from the surface of the resist layer 21c, the resist layer 21c is positioned around the through-hole 21j in the circuit board 21. Therefore, when the through-hole 21j is formed in the circuit board 21 by stamping or the like, the resist layer 21c can suppress the formation of burrs, etc., on the inner edge of the through-hole 21j.

[0051] like Figure 4As shown, the radial width of the second annular contact portion 51 is greater than the radial width of the step portion 35e. This allows the entire step portion 35e to contact the second annular contact portion 51 formed of the resist layer 21c. Consequently, the circuit board 21 can be supported more stably. The radial width of the step portion 35e is the radial dimension between the inner and outer edges of the downward-facing step surface of the step portion 35e.

[0052] In the following description, the same components as those described above are denoted by the same reference numerals and their description may be omitted.

[0053] (Variation 1)

[0054] like Figure 6 As shown, in the motor 111 of this modified example, the circuit substrate 121 has multiple first annular contact portions 45a and multiple first annular adhesive portions 47. In this modified example, two first annular contact portions 45a and two first annular adhesive portions 47 are provided. In this modified example, when viewed from an axial direction perpendicular to the circuit substrate 121, the first annular contact portions 45a and the first annular adhesive portions 47 are provided in multiple layers to surround the connecting portion 39a. Therefore, even if water passes between one first annular adhesive portion 47 and the resin portion 25, the first annular adhesive portions 47 provided further outward from the first annular adhesive portion 47 can suppress the water from spreading. Therefore, the spread of water entering from the first boundary portion 43a onto the circuit substrate 121 can be further suppressed. In this modified example, when viewed from the axial direction, the first annular contact portions 45a and the first annular adhesive portions 47 are provided in multiple layers to surround the connecting portion 39a.

[0055] Although not shown, the second annular contact portion 51 and the second annular adhesive portion 53 may be provided in multiple layers to surround the fitting portion 49 when viewed from the axial direction. This further prevents water entering from the second boundary portion 43b from spreading on the circuit board 121.

[0056] (Variation 2)

[0057] like Figure 7As shown, the circuit substrate 221 of the motor 211 of this modified example has a primer layer 260 laminated on the surface of the substrate main body 21a. The primer layer 260 is, for example, provided on the entire upper and lower surfaces of the substrate main body 21a. In addition, the primer layer 260 may be provided only on a portion of the upper and lower surfaces of the substrate main body 21a. In this modified example, the first annular adhesive portion 247 is formed by the surface of the primer layer 260. Therefore, it is easy to further increase the adhesion between the first annular adhesive portion 247 and the resin portion 25. As a result, it is possible to further suppress the passage of water between the first annular adhesive portion 247 and the resin portion 25, and to further suppress the diffusion of water on the circuit substrate 221. The other structures of the first annular adhesive portion 247 are the same as the other structures of the first annular adhesive portion 47 described above. Although not shown in the figure, the second annular adhesive portion 53 may also be formed by the surface of the primer layer 260. In this case as well, similar to the first annular adhesive portion 247 , it is possible to further suppress the spread of water on the circuit board 221 .

[0058] While the embodiments and modifications of the present invention have been described above, the various structures and combinations thereof in the embodiments and modifications are merely examples, and additions, omissions, substitutions, and other modifications to the structures are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0059] For example, the above embodiments have been described using the example of a motor for a blower, but the purpose of the motor is not limited in any way. Even if it is a motor for other purposes, the present invention can be applied in exactly the same way as the motors of the above structures. In addition, in the above, the case where the first annular contact portion, the first annular adhesive portion, the second annular contact portion, and the second annular adhesive portion are provided in the same motor is described, but it is also possible that only one of the combination of the first annular contact portion and the first annular adhesive portion and the combination of the second annular contact portion and the second annular adhesive portion is provided in the motor. In the above, an example is described in which a part of the stator is exposed from the resin portion. However, the present invention can be applied even if the stator is completely buried in the resin portion. In addition, for example, even if water that penetrates into the interior of the resin portion from a damaged portion of the resin portion reaches the above-mentioned connecting portion or the interlocking portion, the diffusion of water can be suppressed by the first annular adhesive portion or the second annular adhesive portion.

[0060] The first and second annular adhesive portions provided on the circuit substrate may be configured in any manner as long as their adhesion is greater than that of the contact portion provided on the circuit substrate. The first and second annular adhesive portions may be formed by partially laminating a primer layer on the surface of the resist layer to enhance adhesion. The connection portion to the circuit substrate is not limited to the aforementioned configuration and may be any portion.

[0061] In addition, the present technology can adopt the following configurations.

[0062] (1) A motor comprising: a rotor capable of rotating about a central axis; a stator opposed to the rotor with a gap therebetween; a circuit substrate axially overlapping and electrically connected to the stator on one axial side of the stator; a connecting portion connected to the circuit substrate; a resin portion covering at least a portion of the circuit substrate and at least a portion of the connecting portion; and a first boundary portion connecting an outer side surface of the resin portion and the connecting portion, wherein the circuit substrate comprises: a contact portion in contact with the resin portion; and a first annular adhesive portion adhered to the resin portion and annularly surrounding the connecting portion when viewed from a direction perpendicular to the circuit substrate, wherein the adhesion between the first annular adhesive portion and the resin portion is greater than the adhesion between the contact portion and the resin portion.

[0063] (2) A motor according to (1), wherein the circuit substrate comprises: a substrate main body; and an anti-etching layer stacked on the surface of the substrate main body, the contact portion is formed by the surface of the anti-etching layer, and the first annular adhesive portion is formed by the surface of the substrate main body.

[0064] (3) The motor according to (1), wherein the circuit substrate comprises: a substrate main body; and a primer layer laminated on a surface of the substrate main body, and the first annular adhesive portion is formed by a surface of the primer layer.

[0065] (4) A motor according to any one of (1) to (3), wherein the stator has a coil, the coil is electrically connected to the circuit substrate via a conductive component, and the connecting portion includes a portion connected to the circuit substrate in a solder portion connecting the circuit substrate and the conductive component.

[0066] (5) The motor according to (4), wherein the solder portion is connected to a pad portion of the circuit substrate, and when viewed from a direction perpendicular to the circuit substrate, the width of the first annular adhesive portion is greater than the width of the pad portion.

[0067] (6) A motor according to (4) or (5), wherein the contact portion has a first annular contact portion surrounding the solder portion when viewed from a direction perpendicular to the circuit substrate, the first annular contact portion is composed of a surface of an anti-etching layer provided on the circuit substrate, and the first annular adhesive portion surrounds the first annular contact portion when viewed from a direction perpendicular to the circuit substrate.

[0068] (7) The motor according to (6), wherein the first annular contact portion and the first annular adhesive portion are multiplexed so as to surround the connecting portion when viewed from a direction perpendicular to the circuit substrate.

[0069] (8) A motor comprising: a rotor capable of rotating about a central axis; a stator having an insulating member, the stator being opposed to the rotor with a gap therebetween; a circuit substrate having a fitting portion for fitting the insulating member, the circuit substrate and the stator overlapping in the axial direction; a resin portion covering at least a portion of the circuit substrate; and a second boundary portion connecting the outer side surface of the resin portion and the fitting portion, the circuit substrate comprising: a second annular contact portion in contact with the resin portion and surrounding the fitting portion in an annular shape when viewed from a direction perpendicular to the plate surface of the circuit substrate; and a second annular adhesive portion adhered to the resin portion and surrounding the fitting portion in an annular shape when viewed from a direction perpendicular to the plate surface of the circuit substrate, the second annular adhesive portion having a greater adhesion force to the resin portion than the second annular contact portion.

[0070] (9) A blower comprising: the motor according to any one of (1) to (8); and an impeller portion provided on the rotor.

[0071] The structures and methods described above in this specification can be appropriately combined within a range that does not contradict each other.

Claims

1. A motor comprising: a rotor capable of rotating about a central axis; a stator facing the rotor with a gap therebetween; a circuit substrate overlapping with the stator in the axial direction on one axial side of the stator and electrically connected thereto; a connecting portion connected to the circuit substrate; a resin portion covering at least a portion of the circuit substrate and at least a portion of the connecting portion; and a first boundary portion connecting the outer side surface of the resin portion and the connecting portion, The circuit substrate has: a contact portion in contact with the resin portion; and a first annular adhesive portion, which is adhered to the resin portion and surrounds the connecting portion in an annular shape when viewed from a direction perpendicular to the circuit substrate; The adhesion force between the first annular adhesive portion and the resin portion is greater than the adhesion force between the contact portion and the resin portion.

2. The motor according to claim 1, wherein The circuit substrate has: The main body of the substrate; as well as a resist layer laminated on the surface of the substrate main body, The contact portion is formed by the surface of the resist layer, The first annular adhesive portion is formed by a surface of the substrate main body.

3. The motor according to claim 1, wherein The circuit substrate has: a substrate main body; and a primer layer laminated on the surface of the substrate main body, The first annular adhesive portion is formed by the surface of the primer layer.

4. The motor according to claim 1, wherein The stator has a coil, The coil is electrically connected to the circuit board via a conductive member. The connecting portion includes a portion connected to the circuit substrate among the solder portions connecting the circuit substrate and the conductive member.

5. The motor according to claim 4, wherein The solder portion is connected to the pad portion of the circuit substrate, When viewed from a direction perpendicular to the circuit board, the width of the first annular adhesive portion is larger than the width of the land portion.

6. The motor according to claim 4, wherein The contact portion includes a first annular contact portion surrounding the solder portion when viewed from a direction perpendicular to the circuit substrate. The first annular contact portion is formed by a surface of the resist layer provided on the circuit substrate. The first annular adhesive portion surrounds the first annular contact portion when viewed from a direction perpendicular to the circuit substrate.

7. The motor according to claim 6, wherein The first annular contact portion and the first annular adhesive portion are provided in multiple layers so as to surround the connecting portion when viewed from a direction perpendicular to the circuit substrate.

8. A motor comprising: a rotor capable of rotating about a central axis; a stator having an insulator, the stator being opposed to the rotor with a gap therebetween; a circuit substrate having a fitting portion into which the insulating member is fitted, the circuit substrate overlapping the stator in the axial direction; a resin portion covering at least a portion of the circuit substrate; and a second boundary portion connecting the outer side surface of the resin portion and the fitting portion, The circuit substrate has: a second annular contact portion that contacts the resin portion and surrounds the fitting portion in an annular shape when viewed from a direction perpendicular to the surface of the circuit board; and The second annular adhesive portion is bonded to the resin portion and surrounds the fitting portion in an annular shape when viewed from a direction perpendicular to the plate surface of the circuit substrate. The adhesion force between the second annular adhesive portion and the resin portion is greater than the adhesion force between the second annular contact portion and the resin portion.

9. A blower comprising: The motor according to any one of claims 1 to 8; and The impeller portion is provided on the rotor.

Images