CN112615458B

CN112615458B - Motor

Info

Publication number: CN112615458B
Application number: CN202011030389.6A
Authority: CN
Inventors: 鹤壮马; 石川将之; 柳乐一辉
Original assignee: Nidec Techno Motor Corp
Current assignee: Nidec Techno Motor Corp
Priority date: 2019-10-03
Filing date: 2020-09-27
Publication date: 2024-01-09
Anticipated expiration: 2040-09-27
Also published as: CN117748799A; CN112615458A

Abstract

The invention provides a motor, which is provided with a static part and a rotating part rotating through a bearing part. The stationary part has a stator, a housing, a cover holding the bearing part, and a circuit board electrically connected to the stator. The rotating part has a rotor and a shaft. The circuit board has electronic components for driving the motor. The case is opened at the case opening, and accommodates the electronic component in the internal space. The cover covers the housing opening from one axial side of the circuit board. The cover includes a cover main body made of resin and a heat dissipation member attached to the cover main body and having a higher thermal conductivity than the cover main body. The end portion on the other axial side of the heat radiating member is in contact with the electronic component directly or indirectly via other members. The cover body is sandwiched between the bearing portion and the heat radiating member at least in the radial direction. This can sufficiently ensure insulation performance between the electronic component and the heat dissipation member and the bearing portion of the support shaft.

Description

Motor

Technical Field

The present invention relates to a motor.

Background

Conventionally, there are the following molding motors: the stator of the motor is molded with resin to form a housing, in which a rotor is supported via a bearing. Such a motor is excellent in water resistance of the stator, vibration isolation and sound insulation against vibration of the stator when the motor is driven. The conventional molding motor is described in, for example, japanese patent application laid-open No. 2007-6603.

Patent document 1: japanese patent laid-open No. 2007-6603

The DC brushless motor of Japanese patent application laid-open No. 2007-6603 has a stator finished body (6) formed by integrally molding a rotor finished body and a stator. The bearing (5) on the opposite output shaft side is supported by a bracket (10) and fixed to the stator finishing body (6). A printed board (8) on which a drive IC (7) is mounted on the stator completion body (6). A heat dissipation silicon (11) is coated on the bracket (10) and the drive IC (7). A heat sink (12) made of aluminum is attached to the bracket (10). Thus, heat generated in the drive IC (7) can be dissipated through the bracket (10) and the heat dissipation plate (12) via the heat dissipation silicon (11) (except for paragraphs 0016, 0017, and 0020).

A shaft (3) is fixed on the inner ring of the bearing (5). The shaft (3) is connected to a rotating part, a speed reducing mechanism, or the like of equipment for maintenance or the like by an operator. However, as described above, the bearing (5) is supported by the bracket (10), but only the heat dissipation silicon (11) is applied between the bracket (10) and the drive IC (7). Therefore, the insulation performance between the drive IC (7) and the shaft (3) cannot be sufficiently ensured.

Disclosure of Invention

An object of the present invention is to provide a structure capable of ensuring insulation performance between a heat radiation member for promoting heat radiation from an electronic component housed therein and a shaft for connecting a rotating part of a device to be driven, a speed reduction mechanism, and the like in a molded motor having a housing in which a stator is integrally molded. In addition, a structure capable of preventing the bearing from being corroded by electricity is provided.

An exemplary invention 1 of the present application is a motor having a stationary portion; and a rotating unit that rotates about the central axis through the bearing unit. The stationary part has: a stator; a housing that houses at least a portion of the stator; a cover fixed to the housing and directly or indirectly holding the bearing portion; and a circuit board extending in a radial direction and electrically connected to the stator. The rotating part has: a rotor; and a shaft mounted to the rotor and extending along the central axis. The circuit board has an electronic component for driving the motor, and the housing has an inner space that is open at least at a housing opening formed at one side in the axial direction and continuous from the housing opening to the other side in the axial direction. The electronic component is located in the internal space. The cover covers the housing opening from a position on one side of the circuit board in the axial direction, and the cover has: a cover main body made of resin; and a heat dissipation member attached to the cover body portion and having a higher thermal conductivity than the cover body portion. The end portion on the other axial side of the heat radiating member is in contact with the electronic component directly or indirectly via other members. The cover body is sandwiched between the bearing portion and the heat radiating member at least in the radial direction.

An exemplary invention 2 of the present application is a motor having a stationary portion; and a rotating unit that rotates about the central axis through the bearing unit. The stationary part has: a stator that surrounds the central axis in an annular shape and includes a stator core as a magnetic body, the stator core having a plurality of teeth extending in a radial direction; a housing that houses at least a portion of the stator; and a cover fixed to the housing. The bearing portion includes one side bearing and the other side bearing disposed axially apart from each other around the center axis. The housing has: a housing opening formed on one axial side; a housing cylindrical portion extending cylindrically from the housing opening toward the other axial side; a bottom plate portion that extends radially inward from an end portion of the other axial side of the housing cylindrical portion, and that directly or indirectly fixes the other side bearing; and a metallic case-side conduction member extending in the axial direction and electrically conducting with the other side bearing or the stator core. The housing cylindrical portion and the bottom plate portion are one member made of resin. The stator is accommodated in at least one of the housing cylindrical portion and the bottom plate portion. The cover has: a cover main body part made of resin and covering the housing opening part; a metal one-side bearing housing portion fixed to the center of the cover main body portion and holding one-side bearing; and a metallic cover-side conduction member extending in the radial direction, one end of which is electrically conducted to the one-side bearing housing portion, and the other end of which is electrically conducted to the housing-side conduction member.

According to the 1 st aspect of the present application, a resin cover body portion serving as an insulator is interposed between a heat radiating member that promotes heat radiation from an electronic component and a bearing portion that rotatably supports a shaft. This can sufficiently ensure insulation performance between the electronic component and the heat dissipation member and the bearing portion of the support shaft. As a result, the electricity flowing through the circuit board can be suppressed from being transmitted to the shaft via the heat radiation member and the bearing portion.

According to the exemplary invention 2 of the present application, in a molded motor having a resin housing in which a stator is integrally molded, a cover main body portion covering an opening portion of the housing can be easily manufactured by resin molding. Further, a metal cover-side conductive member and a metal case-side conductive member are provided. One end of the cover-side conduction member is electrically conducted to the metal bearing holder portion holding the one-side bearing, and the other end of the cover-side conduction member is electrically conducted to the housing-side conduction member. In addition, one end of the case-side conduction member is electrically conducted to the cover-side conduction member, and the other end of the case-side conduction member is electrically conducted to the other side bearing or the stator core. Thus, the electric erosion of the one-side bearing and the other-side bearing can be prevented.

Drawings

Fig. 1 is a longitudinal sectional view of a motor according to embodiment 1.

Fig. 2 is a perspective view of the cover and the upper bearing housing portion according to embodiment 1.

Fig. 3 is a perspective view of the cover body and the upper bearing housing section according to embodiment 1.

Fig. 4 is a perspective view of a heat radiating member according to embodiment 1.

Fig. 5 is a perspective view of the cover and the upper bearing housing portion according to embodiment 1.

Fig. 6 is a partial longitudinal sectional view of the motor of embodiment 1.

Fig. 7 is a perspective view of a cover and an upper bearing housing portion according to a modification.

Fig. 8 is a partial longitudinal sectional view of a motor of a modification.

Fig. 9 is a partial longitudinal sectional view of a motor of a modification.

Fig. 10 is a partial longitudinal sectional view of the motor of embodiment 2.

Fig. 11 is a perspective view of a cover-side conduction member according to embodiment 2.

Fig. 12 is a perspective view of the cover according to embodiment 2.

Fig. 13 is a perspective view of the case of embodiment 2.

Fig. 14 is a partial bottom view of the motor of embodiment 2.

Fig. 15 is a partial longitudinal sectional view of a motor according to a modification of embodiment 2.

Detailed Description

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In the present application, a direction parallel to the central axis of the motor is referred to as an "axial direction", a direction perpendicular to the central axis of the motor is referred to as a "radial direction", and a direction along an arc centered on the central axis of the motor is referred to as a "circumferential direction". In the present application, the shape and positional relationship of each portion will be described with respect to the stator with respect to the circuit board side, with the axial direction being the up-down direction. However, the vertical direction is not intended to limit the orientation of the motor of the present invention when the motor is manufactured or when the motor is used. That is, in the following embodiments or modifications, "upper side (upper end)" may be read as "one axial side (axial side end)", and "lower side (lower end)" may be read as "other axial side (axial side end)". In the present application, "parallel direction" also includes a substantially parallel direction. In this application, "vertical direction" also includes a substantially vertical direction.

< 1. 1 st embodiment >

1-1 Structure of Motor

Fig. 1 is a longitudinal sectional view of a motor 1. The motor 1 is used for home electric appliances such as an indoor unit and an outdoor unit of an air conditioner. However, the motor of the present invention may be used for applications other than home appliances. For example, the motor of the present invention may be mounted on a transportation device such as an automobile or a railway, an OA device, a medical device, a tool, a large industrial device, or the like to generate various driving forces.

As shown in fig. 1, the motor 1 has a stationary portion 2 and a rotating portion 3. The stationary part 2 is fixed to a housing of a device to be driven. The rotating portion 3 is supported rotatably about a vertically extending central axis 9 with respect to the stationary portion 2 via a bearing portion 60 described later. A rotation unit or a reduction mechanism of a device to be driven is fixed to a shaft 31 of the rotation unit 3, which will be described later.

The stationary part 2 of the present embodiment includes a stator 21, a housing 22, a cover 23, a circuit board 24, and a bearing housing 25. The bearing housing 25 includes an upper bearing housing 251 and a lower bearing housing 252. The upper bearing housing 251 forms a part of the cover 23. The lower bearing housing 252 forms a part of the housing 22. However, for ease of understanding, the housing 23 and the upper bearing housing 251 are distinguished, and the housing 22 and the lower bearing housing 252 are distinguished.

The motor 1 of the present embodiment drives the switching elements of the inverter by high-frequency Pulse Width Modulation (PWM) control. In a motor controlled by a pulse width modulation method, an electrolytic corrosion phenomenon of a bearing is liable to occur. Therefore, the technique of the present invention is particularly useful in motors that perform pulse width modulation control. Although the motor 1 in the present embodiment performs pulse width modulation control, the present invention is not limited to this. The motor may be driven by another control method as long as it is a motor that may cause an electrolytic corrosion phenomenon of the bearing.

The stator 21 is an armature that generates magnetic flux in response to a drive current supplied from an external power source via the circuit board 24. The stator 21 surrounds a radial outer side of a rotor 32 described later in an annular shape. The stator 21 has a stator core 211, an insulator 212, and a plurality of coils 213. Stator core 221 is a magnetic body made of laminated steel plates in which electromagnetic steel plates are laminated in the axial direction. The stator core 211 is fixed to the housing 22. The stator core 211 includes an annular core back 41 and a plurality of teeth 42 protruding radially inward from the core back 41. The core back 41 is disposed substantially coaxially with the central axis 9. The plurality of teeth 42 are arranged at substantially equal intervals in the circumferential direction.

The insulator 212 is made of resin as an insulator. The insulator 212 is mounted to the stator core 211. The upper surface, the lower surface, and both circumferential sides of each tooth 42 are covered with an insulator 212. The coil 213 is formed of a wire wound around the teeth 42 via the insulator 212. The insulator 212 is interposed between the stator core 211 and the coil 213, whereby the stator core 211 and the coil 213 can be prevented from being electrically shorted.

The housing 22 is a resin member for holding the stator 21 and a lower bearing 62 described later. The housing 22 of the present embodiment is an insert molded product obtained by flowing resin into the inside of a mold holding the stator 21 and the lower bearing housing 252. The housing 22 includes a housing cylindrical portion 221, a bottom plate portion 222, a housing-side conduction member 225, and a lower bearing housing portion 252.

The housing cylindrical portion 221 extends in a substantially cylindrical shape in the axial direction. Further, the rotor 32 is disposed radially inward of the housing cylindrical portion 221. In the present embodiment, the surface of the stator 21 other than the end surface on the inner side in the radial direction of the teeth 42 is covered with the resin forming the housing 22. This can suppress the infiltration of water into the stator 21. In addition, the coil 213 of the stator 21 and the stator core 211 can be electrically insulated. However, the entire stator 21 including the radially inner end surfaces of the teeth 42 may be covered with the resin forming the housing 22. That is, the housing 22 may house at least a part of the stator 21. The case cylindrical portion 221 of the present embodiment includes a case main body portion 43 and an end wall portion 44. The case body 43 is a lower portion of the case cylindrical portion 221. The end wall portion 44 is a portion of the housing cylindrical portion 221 including an upper end portion. The end wall portion 44 protrudes upward from the housing main body portion 43. The case main body 43 and the end wall 44 each have a cylindrical shape. However, the thickness of the end wall portion 44 in the radial direction is smaller than that of the case main body portion 43.

The bottom plate portion 222 extends in an annular shape radially inward from the lower end portion of the housing cylindrical portion 221. The bottom plate portion 222 is located below the stator 21 and the rotor 32. In addition, the bottom plate portion 222 covers the outer peripheral surface and a part of the lower surface of the lower bearing housing portion 252, and holds the lower bearing housing portion 252.

The housing 22 further includes an inner space 220 that is opened at a housing opening 223 at the upper end of the housing cylindrical portion 221 and that continues downward from the housing opening 223. A part of the circuit board 24 of the stationary part 2 including the electronic component 26 described later, and the shaft 31 described later of the rotating part 3, and the rotor 32 are located in the internal space 220. This can reduce the size of the motor 1 as a whole in the axial direction. However, the position where the case opening 223 is formed is not limited thereto. The case opening 223 may be formed on at least one of the upper side and the lower side of the case 22.

The cover 23 is a substantially plate-like member that is disposed above the housing 22 and extends radially in an annular shape around the upper bearing housing 251. The cover 23 includes a cover body 231, a heat radiating member 232, a cover-side conduction member 236, and an upper bearing housing 251. The cover 23 of the present embodiment is an insert molded product obtained by flowing resin into a mold holding a heat radiating member 232, an upper bearing housing 251, and a cover-side conductive member 236, which will be described later. The cover body 231 is formed by curing the resin. The cover main body portion 231 covers a part of the outer peripheral surface and the lower surface of the upper bearing housing portion 251, and holds the upper bearing housing portion 251. By providing the resin cover body 231 in this manner, the operation is easier than in the case of manufacturing a metal cover by press molding in the conventional art, and the manufacturing equipment and the mold can be made inexpensive and compact. In addition, the echo (noise) of the cover body 231 generated with the vibration from the motor 1 can be suppressed to be lower than in the case of using a metal cover.

The cover body 231 is expanded in an annular shape radially outward of the upper bearing housing 251. The upper bearing housing 251 and the cover-side conductive member 236 are fixed to the cover main body 231 by being covered with resin forming the cover main body 231. More specifically, the cover main body 231 covers a part of the lower surface and the outer peripheral surface of the upper bearing housing 251, and holds the upper bearing housing 251. The cover main body 231 covers an extension 83 of the cover-side conductive member 236, which will be described later, and holds the cover-side conductive member 236. Thus, the cover-side conduction member 236 and the upper-side bearing housing 251 are not required to be fixed to the cover main body 231 by screws, adhesives, or the like. As a result, the number of components of the motor 1 can be reduced.

An annular groove 230 is formed on the lower surface of the cover body 231. The groove 230 is recessed upward from the lower surface of the peripheral edge portion of the cover body 231. The upper end of the end wall portion 44 of the housing 22 is fitted into the groove portion 230. In addition, the cover 23 and the housing 22 are firmly fixed to each other by press-fitting. The cover body 231 covers the case opening 223 from above the circuit board 24. This suppresses intrusion of water or foreign matter into the interior of the housing 22.

The circuit board 24 expands radially on the upper side of the stator 21 and the rotor 32 and on the lower side of the cover 23. An electronic circuit including an electronic component 26 for driving the motor 1 is mounted on the surface of the circuit board 24. An end portion of a wire (not shown) constituting the coil 213 is led upward and electrically connected to the electronic circuit. That is, the circuit board 24A is electrically connected to the stator 21A. Wires (not shown) extending from an external power supply are electrically connected to the circuit board 24. That is, the coil 213 and the external power supply are electrically connected via the circuit board 24. The current supplied from the external power supply flows to the coil 213 via the circuit board 24A. The circuit board 24 may be electrically connected to a control circuit mounted on the device to be driven, or may receive a signal line from the control circuit.

In addition, the electronic parts 26 are classified into a 1 st electronic part 261 and a 2 nd electronic part 262. The 1 st electronic component 261 is an electronic component that generates heat relatively easily among the electronic components mounted on the circuit board 24. The 1 st electronic component 261 includes, for example, a switching element such as an FET or an IGBT. The 1 st electronic component 261 further includes a power semiconductor in which a plurality of switching elements are housed in one package. The 2 nd electronic component 262 is an electronic component that is relatively less likely to generate heat among the electronic components mounted on the circuit board 24. In the present embodiment, a heat conduction sheet 240 (other member) that contacts the 1 st electronic component 261 is disposed on the upper side of the circuit board 24. For example, an elastic sheet containing silicone rubber and having high thermal conductivity is used as the material of the thermally conductive sheet 240.

The upper bearing housing portion 251 has a substantially cylindrical shape with an upper side closed. As described above, the cover 23 is an insert molded product obtained by flowing resin into the inside of a mold holding the heat radiating member 232 and the upper bearing housing 251 described later. That is, the upper bearing housing 251 is fixed to the cover main body 231 of the cover 23 by molding of a mold resin. The upper bearing housing 251 is fixed to the center of the cover body 231. In addition, an upper end portion of the shaft 31 and an upper bearing portion 61, which will be described later, are housed inside the upper bearing housing portion 251. As a material of the upper bearing housing 251, a conductive metal such as iron or aluminum is used.

The lower bearing housing 252 has a substantially annular shape. As described above, the housing 22 is an insert molded product obtained by flowing resin into the inside of the mold holding the stator 21 and the lower bearing housing 252. That is, the lower bearing housing 252 is fixed to the bottom plate 222 of the housing 22 by molding of a mold resin. Further, a lower bearing housing portion 62 rotatably supporting a shaft 31 described later is housed in the lower bearing housing portion 252. As a material of the lower bearing housing 252, a metal having conductivity such as iron or aluminum is used.

The rotating portion 3 has a shaft 31 and a rotor 32.

The shaft 31 is a columnar member extending in the up-down direction along the central axis 9. The shaft 31 is rotatably supported about the central axis 9. The lower end of the shaft 31 protrudes downward from the lower end of the housing 22. A fan for an air conditioner, which is a rotating part of equipment to be driven, is attached to a lower end portion of the shaft 31, for example. The upper end of the shaft 31 may be connected to a driving unit other than the fan via a power transmission mechanism such as a gear.

In the present embodiment, the shaft 31 protrudes downward, but the present invention is not limited thereto. The shaft 31 may protrude upward from the cover 23, and the upper end thereof may be connected to the driving unit. The shaft 31 may protrude below the housing 22 and above the cover 23, and both the lower end and the upper end thereof may be connected to the driving unit.

The rotor 32 is an annular member disposed radially inward of the stator 21 and around the shaft 31, and rotates together with the shaft 31. The rotor 32 has a rotor core 321 and a plurality of magnets 322.

The rotor core 321 is formed of laminated steel plates in which electromagnetic steel plates are laminated in the axial direction. A rotor through hole 320 is provided radially inward of the rotor core 321. The rotor through hole 320 penetrates the rotor 32 in the axial direction along the central axis 9. The shaft 31 is inserted into the rotor through hole 320, and is press-fitted to the inner peripheral surface of the rotor core 321. However, the shaft 31 may be attached to the rotor core 321 by adhesion instead of or in addition to press-fitting.

A plurality of magnets 322 are arranged around the rotor core 321. The radially outer surface of each magnet 322 is a magnetic pole surface facing the radially inner end surface of the tooth 42 of the stator 21. The plurality of magnets 322 are arranged at equal intervals in the circumferential direction so that the magnetic pole faces of the N poles and the magnetic pole faces of the S poles are alternately arranged.

Instead of the plurality of magnets 322, a ring-shaped magnet may be used. In the case of using a ring-shaped magnet, the N pole and the S pole may be magnetized alternately in the circumferential direction on the outer circumferential surface of the magnet. The plurality of magnets 322 may be disposed around the rotor core 321 as in the present embodiment, or may be disposed so as to be embedded in the rotor core 321.

The bearing portion 60 includes an upper bearing portion 61 and a lower bearing portion 62. The upper bearing 61 rotatably supports the shaft 31 above the rotor 32. The lower bearing 62 rotatably supports the shaft 31 below the rotor 32. The upper bearing portion 61 and the lower bearing portion 62 of the present embodiment are each a ball bearing having a ball 601, an outer race 602, and an inner race 603. In the ball bearing, an outer ring 602 and an inner ring 603 relatively rotate via a ball 601. As a material of the ball 601, the outer ring 602, and the inner ring 603, a conductive metal such as iron is used. That is, the outer peripheral surface and the inner peripheral surface of the upper bearing portion 61 and the lower bearing portion 62 are connected by a member having conductivity.

In the present embodiment, the sphere 601, the outer ring 602, and the inner ring 603 are formed entirely of a conductive material, but the present invention is not limited thereto. For example, even if an insulating material is used for a part of the upper bearing portion 61 and the lower bearing portion 62, the outer peripheral surface and the inner peripheral surface of the upper bearing portion 61 and the lower bearing portion 62 may be connected by a conductive member. In the present embodiment, a ball bearing is used as the bearing, but other types of bearings such as a sleeve bearing may be used as long as the bearing has conductivity between the outer peripheral surface and the inner peripheral surface.

The outer ring of the upper bearing 61 is fixed to the upper bearing housing 251. Thereby, the outer ring of the upper bearing 61 is electrically connected to the upper bearing housing 251. The outer ring of the lower bearing portion 62 is fixed to the lower bearing housing portion 252. Thus, the outer ring of the lower bearing portion 62 is electrically connected to the lower bearing housing portion 252. Further, the inner rings of the upper bearing 61 and the lower bearing 62 are fixed to the shaft 31.

When the motor 1 is driven, power is supplied from an external power source to the 1 st electronic component 261 and the 2 nd electronic component 262 on the circuit board 24. The 1 st electronic part 261 and the 2 nd electronic part 262 generate a driving current for energizing the coil 213, and control energization. By supplying a driving current to the coil 213, magnetic fluxes are generated on the plurality of teeth 42 of the stator core 211. Then, a circumferential torque is generated by an action of magnetic flux between the teeth 42 and the magnets 322 mounted on the rotor 32. As a result, the rotating unit 3 rotates around the central axis 9. In addition, the device directly or indirectly mounted on the shaft 31 rotates together with the rotating portion 3.

As described above, the upper bearing 61 is supported by the upper bearing housing 251 made of metal. The lower bearing portion 62 is supported by a lower bearing housing 252 made of metal. As a result, even when the temperature of each portion increases during driving of the motor 1, relative dimensional changes and deformation between the upper bearing portion 61 and the upper bearing housing portion 251 and between the lower bearing portion 62 and the lower bearing housing portion 252 can be suppressed. Therefore, the rotation portion 3 is prevented from idling, and high rotation accuracy is maintained.

Detailed structure of cover 1-2

Next, a more detailed construction of the cover 23 will be described.

Fig. 2 is a perspective view of the cover 23 and the upper bearing housing 251. As shown in fig. 2, the cover 23 has the cover body 231 and the heat radiating member 232 described above. The cover body 231 is made of resin. On the other hand, a metal such as aluminum is used as the material of the heat radiating member 232. Therefore, the heat dissipation member 232 has a higher thermal conductivity than the cover main body 231.

Fig. 3 is a perspective view of the cover body 231 and the upper bearing housing 251 from above. Fig. 4 is a perspective view of the heat radiating member 232. Fig. 5 is a perspective view of the cover 23 and the upper bearing housing 251 from below. As shown in fig. 3, the cover body 231 formed by injection molding of resin has a plate-like portion 51 and a hole portion 52. The plate-like portion 51 is expanded in a plate-like manner in the horizontal direction. The hole 52 is a trace of the heat radiation member 232 disposed at the time of injection molding of the resin, and penetrates the plate-like portion 51 in the axial direction. That is, as shown in fig. 2 to 4, in the cover 23 formed by injection molding of resin, the heat radiating member 232 is disposed in the hole 52 and attached to the cover main body 231. As shown in fig. 5, the heat radiating member 232 is exposed downward of the cover 23.

As shown in fig. 1, the lower end portion of the heat radiating member 232 is indirectly in contact with the 1 st electronic component 261 via the heat conductive sheet 240 having high heat conductivity. As shown in fig. 2 and 4, a plurality of fins 71 exposed to the outside of the motor 1 are provided on the upper surface of the heat radiating member 232. Each fin 71 is a protrusion protruding upward. This allows heat generated in the 1 st electronic component 261 to be radiated from the heat radiating member 232 to the outside of the motor 1 via the heat conducting fin 240. In particular, in the present embodiment, the heat radiation member 232 is exposed to the lower side of the cover 23 and is not in direct contact with the heat conduction sheet 240 via the air layer, so that the heat radiation performance is further improved. In addition, the heat conductive sheet 240 may not be provided. That is, the lower end portion of the heat dissipation member 232 may be in direct contact with the 1 st electronic component 261 without via the heat conduction sheet 240.

Further, the 2 nd electronic component 262, which is relatively less likely to generate heat, is axially away from the plate-like portion 51 of the cover 23. The 2 nd electronic component 262 includes, for example, an IC component or the like. The lower end portion of the heat radiating member 232 of the present embodiment is located below the plate-like portion 51. Thus, the 1 st electronic component 261 and the heat dissipation member 232 can be brought into contact without bringing the 2 nd electronic component 262 and the cover main body portion 231 into contact.

As shown in fig. 4, the heat radiating member 232 includes fixing portions 72 on the outer sides of the plurality of fins 71 in the horizontal direction. The fixing portion 72 extends substantially perpendicularly with respect to the axial direction. However, the fixing portion 72 may be slightly inclined from a direction substantially perpendicular to the axial direction. When the cover 23 is resin molded, the heat radiating member 232 is fixed by the side face 721 of the fixing portion 72 and the lower end face 722 of the fixing portion 72 being covered with the resin forming the cover main body portion 231. This prevents the heat radiating member 232 from coming off the cover body 231 in the axial direction. Further, since the heat radiating member 232 can be attached to the cover main body 231 without using screws, adhesive materials, or the like, the gap between the heat radiating member 232 and the cover main body 231 is almost eliminated. Therefore, even if water splashes onto the cover 23 from the outside of the motor 1, the water can be suppressed from entering the inside of the motor 1. However, the side face 721 of the fixing portion 72 and the upper end face 723 of the fixing portion 72 of the heat radiating member 232 may be covered with the resin forming the cover main body portion 231. That is, the heat dissipation member 232 may be fixed by covering at least a part of the side face 721 of the fixing portion 72, the upper end face 723 of the fixing portion 72, and the lower end face 722 with the resin forming the cover body portion 231.

As shown in fig. 4, the heat radiating member 232 further has an axial extension 73 extending in the axial direction on the lower side of the plurality of fins 71. As shown in fig. 5, the cover body 231 has a 1 st protruding portion 53. The 1 st protruding portion 53 protrudes downward from the plate-like portion 51 at the peripheral edge portion of the hole portion 52. In the present embodiment, the entirety of the side surface of the axially extending portion 73 of the heat radiating member 232 is covered with the resin forming the 1 st protruding portion 53. Thereby, the area of the resin-covered heat dissipation member 232 forming the cover main body 231 increases. As a result, even when the heat radiating member 232 receives an external force, tilting or dropping can be suppressed. However, at least a part of the side surface of the axially extending portion 73 of the heat radiating member 232 may be covered with the resin forming the cover main body portion 231.

As shown in fig. 3, a stepped portion 521 is formed at the peripheral edge portion of the hole 52 in the upper end portion of the cover main body portion 231. The step 521 is recessed below the upper surface of the plate 51. The stepped portion 521 is further expanded in a direction perpendicular to the axial direction as compared with other portions of the hole portion 52. The stepped portion 521 includes a portion of the heat dissipation member 232 located at a lower part of the plurality of fins 71 and the fixing portion 72. That is, the portions of the heat dissipation member 232 that are lower than the plurality of fins 71 are located in the hole 52, and the portions that protrude upward from the cover body 231 are smaller. This can suppress the height of the motor 1 in the axial direction. However, it is also possible to dispose all of the plurality of fins 71 of the heat radiating member 232 in the hole 52 by providing the stepped portion 521 deeper.

Fig. 6 is a partial longitudinal sectional view of the motor 1. As shown in fig. 6, the upper bearing housing 251 has a cylindrical portion 91 and a flange portion 92. The cylindrical portion 91 extends cylindrically along the central axis 9. Further, an upper bearing portion 61 is disposed inside the cylindrical portion 91. The flange 92 extends radially outward from the lower end of the cylindrical portion 91. The cover body 231 has an annular 2 nd protruding portion 54. The 2 nd projection 54 projects downward from the radially inner end of the plate-like portion 51. A part of the 2 nd protrusion 54 in the circumferential direction constitutes a part of the 1 st protrusion 53. The flange 92 of the upper bearing housing 251 is covered with the resin forming the 2 nd protrusion 54.

Thus, a part of the resin cover body 231 serving as an insulator is interposed between the upper bearing housing 251 and the upper bearing 61, and the heat sink 232 and the electronic component 26. As a result, electrical insulation properties between the upper bearing housing 251 and the upper bearing 61 and the heat dissipation member 232 and the electronic component 26 can be sufficiently ensured. Further, the transmission of electricity flowing through the circuit board 24 on which the 1 st electronic component 261 and the 2 nd electronic component 262 are mounted to the shaft 31 via the heat radiating member 232, the upper bearing housing portion 251, and the upper bearing portion 61 can be suppressed. In particular, in the present embodiment, the insulation distance can be ensured to be longer by sandwiching the 2 nd protruding portion 54 extending in the axial direction between the upper bearing housing portion 251 and the electronic component 26 and the upper bearing portion 61.

Further, by resin molding the cover 23 having such a structure, a structure capable of insulating between the heat radiating member 232 and the electronic component 26 and the upper bearing portion 61 and an upper bearing housing portion 251 holding the upper bearing portion 61 can be simultaneously formed. This can shorten the manufacturing process. In the present embodiment, the cylindrical portion 91 of the upper bearing housing 251 is located below the upper end of the motor 1. This suppresses the height of the motor 1 in the axial direction while maintaining the fixing strength of the upper bearing housing 251 with respect to the cover body 231.

As shown in fig. 4, the fixing portion 72 of the heat radiating member 232 is formed in a mesa shape extending perpendicularly to the axial direction from the plurality of fins 71. As shown in fig. 2, the upper end surface of the mesa shape is an exposed surface 724 exposed to the outside of the motor 1 from the cover body 231. In order to prevent the heat radiating member 232 fitted into the cover 23 from floating when the cover 23 is resin-molded, the peripheral edge portions of the plurality of heat radiating fins 71 are pressed from above by a mold. As a result, after the resin molding, the peripheral edge portions of the plurality of fins 71 become exposed surfaces 724 exposed to the outside. When water splashes onto the cover 23 from the outside of the motor 1, water is likely to accumulate on the exposed surface 724.

Therefore, the cover body 231 of the present embodiment is also formed with a groove 55. The groove 55 is recessed downward from a part of the upper end surface of the cover body 231, and connects the outer peripheral surface of the cover body 231 to the hole 52. The groove 55 is continuous with the exposed surface 724. Thus, even if water splashes onto the cover 23 from the outside of the motor 1, water can be discharged through the groove 55 without accumulating on the exposed surface 724.

< 2. Modification >

The exemplary embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments

The upper bearing housing 251 and the lower bearing housing 252 may not be provided. For example, the upper bearing 61 may be directly fixed to the cover body 231 of the cover 23 without passing through the upper bearing housing 251. That is, the cover 23 may be configured to directly or indirectly hold the upper bearing portion 61. Further, at least a part of the resin cover body 231 serving as an insulator may be sandwiched between the upper bearing 61 and the heat radiating member 232 in the radial direction. This can sufficiently ensure the electrical insulation performance between the upper bearing portion 61 and the heat dissipation member 232 and the electronic component 26. The lower bearing 62 may be directly fixed to the bottom plate 222 of the housing 22 without passing through the lower bearing housing 252. That is, the housing 22 may be configured to directly or indirectly hold the lower bearing portion 62.

Fig. 7 is a perspective view of the cover 23B and the upper bearing housing portion of one modification from above. In the example of fig. 7, the surface 234B of the cover body 231B constituting the hole 52B is inclined in a direction away from the radial center of the hole 52B as it goes upward. That is, the radial width of the hole 52B increases as it goes upward. This makes it possible to smoothly flow air flowing out of the motor 1 from the outside of the motor 1 into the hole 52B and further from the hole 52B. As a result, the heat radiation performance of the heat radiation member 232B is further improved.

Fig. 8 is a partial longitudinal sectional view of a motor 1C according to another modification. As shown in the example of fig. 8, the fixing portion 72C of the heat radiating member 232C may be slightly inclined with respect to the horizontal direction. In this case, at least a part of the side face 721C of the fixing portion 72C, the upper end face 723C and the lower end face 722C of the fixing portion 72C of the heat radiating member 232C is also covered with the resin forming the cover main body portion 231C, thereby firmly fixing the heat radiating member 232C.

Fig. 9 is a partial longitudinal sectional view of a motor 1D according to another modification. In the example of fig. 9, the heat radiating member 232D has a plurality of fins 71D, a fixing portion 72D, and an axial extending portion 73D. The axial extension 73D extends in the axial direction on the lower side of the plurality of fins 71D. The fixing portion 72D extends substantially perpendicularly to the axial direction outside the lower end portion of the axial extending portion 73D. The heat radiating member 232D is firmly fixed by covering the side face 721D of the fixing portion 72D and the upper end face 723D of the fixing portion 72D with a resin forming the cover main body portion 231D. In addition, by the heat radiating member 232D having such a configuration, falling off and falling off from the cover 23D are prevented.

1-2 detailed Structure of case-side conduction Member and cover-side conduction Member

Next, a more detailed configuration of the case-side conductive member 225 and the cover-side conductive member 236 will be described. As the material of the case-side conductive member 225 and the cover-side conductive member 236, a metal having conductivity such as iron (for example, SPCC), brass, or copper is used.

Fig. 11 is a perspective view of the cover-side conductive member 236. As shown in fig. 11, the cover-side conductive member 236 is a thin plate-like member. The cover-side conductive member 236 is manufactured by, for example, cutting and punching a sheet of metal material. In addition, the cap-side conductive member 236 is embedded in the resin forming the cap body 231 and extends in the radial direction. The cover-side conductive member 236 includes a contact portion 81, a mounting portion 82, and an extension portion 83. The contact portion 81 is located at the radially outer end of the cover-side conductive member 236. The mounting portion 82 is located at a radially inner end of the cover-side conductive member 236. The extension 83 connects the contact portion 81 and the mounting portion 82.

Fig. 12 is a perspective view of the cover 23. As a preliminary stage of the resin molding cover 23, the mounting portion 82 of the cover-side conductive member 236 is mounted to the flange portion 92 of the upper bearing housing portion 251. Then, the resin is flowed into the mold holding the cap-side conductive member 236 and the upper-side bearing housing 251. In order to prevent the cover-side conductive member 236 and the upper-side bearing housing 251 from floating or warping due to the flow of resin, pins or the like are used to press the cover-side conductive member 236 and the upper-side bearing housing 251 at a plurality of locations (two locations in the present embodiment). Thus, the formed cover body 231 has the 1 st hole 64 and the 2 nd hole 65 as traces of the pin or the like. The 1 st hole 64 and the 2 nd hole 65 are recessed from the upper side of the lower side of the cover main body 231, respectively. In the 1 st hole 64, a part of the mounting portion 82 of the cover-side conduction member 236 is exposed to the outside of the cover main body 231. In the 2 nd hole 65, a part of the extension 83 of the cover-side conduction member 236 is exposed to the outside of the cover body 231.

The mounting portion 82 of the cover-side conductive member 236 is attached to the flange portion 92 of the upper bearing housing portion 251 by thermal compression bonding. Thereby, the cover-side conduction member 236 is electrically conducted to the upper-side bearing housing 251. However, the mounting portion 82 of the cover-side conductive member 236 may be mounted on the flange portion 92 of the upper bearing housing 251 by screw fastening, welding, soldering, crimping, or adhesive bonding.

As described above, at least a part of the extension 83 of the cover-side conductive member 236 is embedded in the resin forming the cover main body 231. Thus, even when the electronic component 26 or the like is disposed below the extension 83, the insulation between the electronic component 26 and the cover-side conductive member 236 can be improved.

In the motor 1 of the present embodiment, in order to further miniaturize the entire motor 1 in the axial direction, the upper bearing housing 251 and a part of the upper bearing 61 are disposed below the upper end portion of the housing 22. Thus, the upper end of the end wall 44 is located above the lower surface of the flange 92 of the upper bearing housing 251.

Therefore, the cover-side conductive member 236 of the present embodiment is provided with a stepped portion 84 extending in the axial direction between the contact portion 81 and the mounting portion 82. Thus, the axial position of the contact portion 81 is located above the axial position of the mounting portion 82. As shown in fig. 12, the cover body 231 further includes a protrusion 237. The protrusion 237 protrudes further downward from the lower surface of the cover body 231. The portion of the extension 83 of the cover-side conduction member 236 radially inward of the step 84 is covered with the resin forming the protruding portion 237. A portion of the extension 83 of the cover-side conduction member 236 radially outward of the step 84 is covered with resin forming a portion of the cover main body 231 radially outward of the protrusion 237. In this way, by forming the cover-side conduction member 236 and the cover main body portion 231 in a shape that takes into account the difference in height between the upper end portion of the end wall portion 44 of the housing 22 and the lower surface of the flange portion 92 of the upper bearing housing portion 251, the amount of resin used for molding of the cover main body portion 231 can be reduced. Further, since the cover-side conductive member 236 is formed in a thin plate shape as described above, the step 84 can be easily formed by pressing or the like. However, instead of providing the step portion 84, the extension portion 83 may be formed in a shape that inclines at least a portion between the contact portion 81 and the mounting portion 82 at a constant inclination angle. That is, the axial position of the contact portion 81 may be higher (axially one side) than the axial position of the mounting portion 82.

As shown in fig. 12, the cover body 231 includes a 1 st projection 233 and a 2 nd projection 234. The 1 st projection 233 projects radially outward from the groove 230, i.e., downward from the outer peripheral portion of the cover body 231. The 2 nd protrusion 234 protrudes downward from the cover body 231 at a position radially inward of the 1 st protrusion 233 and the groove 230. Further, the contact portion 81 of the cover-side conductive member 236 is located at the groove portion 230. In the present embodiment, the entire contact portion 81 is exposed to the outside of the cover body portion 231. However, at least a part of the contact portion 81 may be exposed to the outside of the cover body portion 231.

Fig. 13 is a perspective view of the housing 22. As shown in fig. 10 and 13, the case-side conduction member 225 extends in the substantially axial direction along the outer peripheral surface of the case 22. The case-side conductive member 225 has a 1 st terminal 2251, a 2 nd terminal 2252, and a wire part 2253. The 1 st terminal 2251 is located at an upper end of the case-side conductive member 225. The 2 nd terminal 2252 is located at the lower end of the case-side conductive member 225. The wire part 2253 connects the 1 st terminal 2251 and the 2 nd terminal 2252. The upper end of the wire part 2253 is connected to the 1 st terminal 2251 to be electrically conductive. The lower end of the wire part 2253 is connected to the 2 nd terminal 2252 to be electrically conductive.

As shown in fig. 10, the 1 st terminal 2251 of the present embodiment includes a base end portion 511, a bent portion 512, and an extension portion 513. The base end portion 511 extends in a substantially axial direction from an upper end portion of the wire portion 2253 toward the upper side. The buckling portion 512 extends radially inward from the upper end portion of the base end portion 511. The extension portion 513 is located at the tip of the 1 st terminal 2251, and extends in a substantially axial direction from the radially inner end of the buckling portion 512 downward. The base end portion 511 is disposed on the outer peripheral surface of the end wall portion 44 of the housing 22, the buckling portion 512 is disposed on the upper end surface of the end wall portion 44, and the extension portion 513 is disposed on the inner peripheral surface of the end wall portion 44. However, the shape of the upper end of the case-side conduction member 225 is not limited thereto. At least a part of the case-side conduction member 225 may be located on the upper end surface of the end wall portion 44.

As described above, the end wall portion 44 is pressed into the cover 23 at the groove portion 230 provided between the 1 st protruding portion 233 and the 2 nd protruding portion 234 of the cover main body portion 231 in the radial direction. At this time, the contact portion 81 of the cover-side conduction member 236 and the bent portion 512 of the case-side conduction member 225 located at the upper end face of the end wall portion 44 are brought into contact by being sandwiched between the end wall portion 44 and the cover main body portion 231. Thereby, the cover-side conductive member 236 is electrically conductive with the case-side conductive member 225.

A bottom surface 235 (see fig. 13) of the groove 230 is located above the end wall 44, and extends in a substantially circular shape along an upper end surface of the end wall 44. The 1 st protruding portion 233 of the cover body 231 protrudes downward from the radially outer end of the bottom surface 235, and extends in a substantially circular arc shape in a top view. The 2 nd projection 234 projects downward from the radially inner end of the bottom surface 235 in a substantially cylindrical shape. A part of the base end portion 511 of the 1 st terminal 2251 is disposed between the outer peripheral surface of the end wall portion 44 and the 1 st protruding portion 233. The buckling portion 512 is disposed between the upper end surface of the end wall portion 44 and the bottom surface 235 of the groove 230. The extension portion 513 is disposed between the inner peripheral surface of the end wall portion 44 and the 2 nd protruding portion 234.

That is, in the present embodiment, the 1 st terminal 2251 having a hook shape is hooked to the upper end portion of the end wall portion 44. In the groove 230, the 1 st terminal 2251 is covered by the cover body 231 to hold the 1 st terminal 2251. Thereby, the 1 st terminal 2251 is more reliably fixed. In addition, the 1 st terminal 2251 is more reliably in contact with the contact portion 81 of the cap-side conductive member 236.

As described above, the end wall portion 44 and the cover body portion 231 are firmly fixed to the groove portion 230 by press fitting. Thereby, separation of the cover-side conductive member 236 and the case-side conductive member 225 due to the floating of the cover 23 is suppressed. In addition, the contact portion 81 of the cover-side conductive member 236 is located in the groove 230. Therefore, the contact portion 81 can be prevented from interfering with the fitting of the housing 22 and the cover 23.

In the present embodiment, the cover-side conductive member 236 is in contact with the case-side conductive member 225 on the lower surface of the cover body 231. This can further shorten the axial length of the case-side conductive member 225 and electrically connect the case-side conductive member 225 and the cover-side conductive member 236.

Next, the wire part 2253 of the case-side conduction member 225 extends downward from the 1 st terminal 2251 along the outer peripheral surface of the case cylindrical part 221. The wire part 2253 is coated with, for example, a resin. The housing 22 has two wall portions 224 on the outer peripheral surface of the housing cylindrical portion 221. The two wall portions 224 extend in a substantially axial direction. The wire part 2253 is disposed between the two wall parts 224 at the outer peripheral surface of the housing cylindrical part 221. This can suppress damage or hooking of the case-side conductive member 225. The housing 22 may have three or more wall portions 224.

Fig. 14 is a partial bottom view of the motor 1. As shown in fig. 14, the wire part 2253 extends radially inward from the lower end of the outer peripheral surface of the housing cylindrical part 221 along the lower surface of the bottom plate part 222. As described above, the 2 nd terminal 2252, which is a circular terminal, is fixed to the end of the wire part 2253 on the opposite side from the 1 st terminal 2251, for example, by crimping.

The lower bearing housing 252 has a housing cylindrical portion and a flange portion 92, similar to the upper bearing housing 251. The flange 92 is provided with a screw hole 250. The 2 nd terminal 2252 is screwed into the screw hole 250 of the lower bearing housing 252 by a metal screw 900. Thereby, the 2 nd terminal 2252 is electrically connected to the lower bearing housing 252.

As described above, the outer ring 602 of the upper bearing 61 is electrically connected to the upper bearing housing 251, and the upper bearing housing 251 is electrically connected to one end of the cap-side conductive member 236. In addition, the other end of the cap-side conductive member 236 is electrically conductive with the 1 st terminal 2251 of the case-side conductive member 225. In addition, the 2 nd terminal 2252 of the case-side conduction member 225 is electrically conducted to the lower-side bearing housing portion 252, and the lower-side bearing housing portion 252 is electrically conducted to the outer ring 602 of the lower-side bearing 62. That is, the upper bearing 61 and the lower bearing 62 are electrically connected by the cover-side conductive member 236 and the case-side conductive member 225. This makes the upper bearing 61 and the lower bearing 62 at the same potential, thereby suppressing potential difference. As a result, the current to be flown between the upper and lower bearings 61 and 62 and the shaft 31 is reduced, and the electrolytic corrosion phenomenon in the upper and lower bearings 61 and 62 is suppressed.

In particular, in the present embodiment, by using the metal cover-side conductive member 236 and the metal case-side conductive member 225, even if the cover main body portion 231 is made of resin, the structure for preventing the electric corrosion of the upper bearing 61 and the lower bearing 62 can be easily formed. Thus, the manufacturing operation of the motor 1 is easier than in the case of manufacturing a metal cover by press molding in the prior art, and the manufacturing equipment and the mold can be made inexpensive and compact. As a result, the manufacturing cost of the motor 1 can be reduced.

In the above embodiment, the hook shape of the case-side conduction member 225 hooked to the upper end portion of the end wall portion 44 of the case 22 may be oriented in the opposite direction. Fig. 7 is a partial longitudinal sectional view of a motor 1B of a modification. In the modification of fig. 7, the lead portion 2253B of the case-side conductive member 225B extends along the inner peripheral surface of the end wall portion 44B of the case 22B. The 1 st terminal 2251B of the case-side conductive member 225B is directed radially outward from the wire part 2253B through the upper end surface of the end wall part 44B. Even with such a structure, the 1 st terminal 2251B can be electrically connected to the contact portion 71B of the cap-side conductive member 236B. Further, by disposing the wire part 2253B inside the end wall part 44B as in the present modification, the wire part 2253B can be prevented from being damaged or detached by contact with an operator or an object outside the motor 1B.

The shape of the details of each member may be different from the shape shown in each drawing of the present application. In addition, the elements appearing in the above-described embodiments and modifications may be appropriately combined within a range where no contradiction occurs.

The present invention can be applied to a motor.

Claims

1. A motor, comprising:

a stationary part; and

a rotating part which rotates around the central axis through the bearing part,

the stationary part has:

a stator;

a housing that houses at least a portion of the stator;

a cover fixed to the housing and directly or indirectly holding the bearing portion; and

a circuit board extending radially and electrically connected to the stator,

the rotating part has:

a rotor; and

a shaft mounted to the rotor and extending along the central axis,

the circuit board has electronic components for driving the motor,

the housing has an inner space which is opened at least at a housing opening formed on one side in the axial direction and which is continuous from the housing opening to the other side in the axial direction,

the electronic component is located in the inner space,

it is characterized in that the method comprises the steps of,

the cover covers the housing opening from a position on one side of the circuit board in the axial direction,

And the cover has:

a cover main body made of resin; and

a heat radiating member attached to the cover main body portion and having a higher thermal conductivity than the cover main body portion,

the other axial side end of the heat dissipation member is in contact with the electronic component directly or indirectly via other members,

the cover main body portion is sandwiched between the bearing portion and the heat radiating member at least in a radial direction,

the cover main body portion includes:

a plate-like portion that expands in a plate-like manner; and

a hole portion penetrating the plate-like portion in the axial direction,

the heat dissipation member is disposed in the hole portion, and an end portion of the heat dissipation member on the other side in the axial direction is located on the other side in the axial direction from the plate-like portion,

the heat dissipation member further has a plurality of fins exposed to the outside of the motor,

a part or all of the other axial side of the plurality of fins is located in the hole.

2. The motor according to claim 1, wherein,

the cover further includes a metal bearing housing portion fixed to the cover main body portion, the bearing portion being disposed inside,

the cover body portion is interposed between the bearing housing portion and the heat radiating member.

3. The motor according to claim 2, wherein,

the electronic component has a 1 st electronic component and a 2 nd electronic component,

the 1 st electronic component is in contact with the heat dissipation member directly or indirectly via other components,

the 2 nd electronic component is away from the plate-like portion.

4. The motor according to claim 3, wherein,

the heat dissipation member has a fixing portion extending perpendicularly to an axial direction,

the heat radiating member is fixed by covering at least a part of the side surface of the fixing portion, the end surface of one side in the axial direction and the end surface of the other side in the axial direction with a resin forming the cover main body portion.

5. The motor according to claim 3, wherein,

the cover main body portion further has a 1 st protruding portion protruding from the plate-like portion to the other side in the axial direction at a peripheral edge portion of the hole portion,

at least a part of the side surface of the heat radiating member is covered with a resin forming the 1 st protruding portion.

6. The motor according to claim 3, wherein,

the bearing housing section has:

a cylindrical portion in which the bearing portion is disposed, the cylindrical portion extending cylindrically along the central axis; and

A flange portion that extends radially outward from an end portion of the cylindrical portion on the other axial side,

the cover main body portion further has a 2 nd protruding portion protruding from a radially inner end portion of the plate-like portion to the other side in the axial direction,

the flange portion is covered with a resin forming the 2 nd protruding portion,

the cylindrical portion is located at the other axial side of the one axial end of the motor.

7. The motor according to claim 3, wherein,

the heat dissipation member has a mesa portion extending perpendicularly from the plurality of fins to an axial direction,

an end surface of one side in the axial direction of the table portion has an exposed surface exposed to the outside from the cover main body portion,

the cover main body portion further includes a groove portion recessed from a part of an end surface on one side in the axial direction to the other side in the axial direction, and the outer peripheral surface of the cover main body portion is connected to the hole portion,

the groove portion is continuous with the exposed surface.

8. The motor according to claim 3, wherein,

the surface of the cover body constituting the hole is inclined in a direction away from a radial center of the hole as it goes to one side in the axial direction.

9. The motor according to any one of claims 1 to 8, wherein,

The heat dissipation member is made of metal.

10. A motor, comprising:

a stationary part; and

a rotating part which rotates around the central axis through the bearing part,

the stationary part has:

a stator;

a housing that houses at least a portion of the stator;

a circuit board extending radially and electrically connected to the stator,

the rotating part has:

a rotor; and

a shaft mounted to the rotor and extending along the central axis,

the circuit board has electronic components for driving the motor,

the electronic component is located in the inner space,

it is characterized in that the method comprises the steps of,

and the cover has:

a cover main body made of resin;

a heat radiation member attached to the cover main body portion and having a higher thermal conductivity than the cover main body portion; and

a metal bearing housing portion fixed to the cover body portion, the bearing portion being disposed inside,

the cover main body portion is interposed between the bearing housing portion and the heat radiating member at least in a radial direction,

the cover main body portion includes:

a plate-like portion that expands in a plate-like manner; and

a hole portion penetrating the plate-like portion in the axial direction,

the bearing housing section has:

the cover main body portion further has a 1 st protruding portion protruding from the plate-like portion to the other side in the axial direction at a peripheral edge portion of the hole portion, and a 2 nd protruding portion protruding from an end portion of the plate-like portion on the inner side in the radial direction to the other side in the axial direction,

the flange portion is covered with a resin forming the 2 nd protruding portion,

11. The motor of claim 10, wherein the motor is configured to control the motor,

the 2 nd electronic component is away from the plate-like portion.

12. The motor of claim 11, wherein the motor is configured to control the motor,

13. The motor of claim 11, wherein the motor is configured to control the motor,

14. The motor of claim 11, wherein the motor is configured to control the motor,

15. The motor of claim 13, wherein the motor is configured to control the motor,

the groove portion is continuous with the exposed surface.

16. The motor of claim 13, wherein the motor is configured to control the motor,

17. The motor according to any one of claims 10 to 16, wherein,

the heat dissipation member is made of metal.

18. A motor, comprising:

a stationary part; and

a rotating part which rotates around the central axis through the bearing part,

the stationary part has:

a stator that surrounds the central axis in an annular shape, and that includes a stator core as a magnetic body, the stator core having a plurality of teeth extending in a radial direction;

a housing that houses at least a portion of the stator; and

a cover secured to the housing,

the bearing portion includes a one-side bearing and another-side bearing disposed axially apart from each other around the central axis,

It is characterized in that the method comprises the steps of,

the housing has:

a housing opening formed on one axial side;

a housing cylindrical portion extending cylindrically from the housing opening toward the other axial side;

a housing bottom portion that extends radially inward from an end portion of the housing cylindrical portion on the other side in the axial direction, and that directly or indirectly fixes the other side bearing; and

a metallic case-side conduction member extending in an axial direction and electrically conducting with the other side bearing or the stator core,

the housing cylindrical portion and the housing bottom portion are made of one resin member,

the stator is accommodated in at least one of the housing cylindrical portion and the housing bottom portion,

the cover has:

a cover main body part made of resin and covering the housing opening part;

a metal one-side bearing holder portion fixed to the center of the cover main body portion and holding the one-side bearing;

a metallic cover-side conduction member extending in a radial direction, one end of which is electrically conducted to the one-side bearing holder portion, and the other end of which is electrically conducted to the housing-side conduction member;

a 1 st protruding portion protruding from an outer peripheral portion of the cover main body portion toward the other axial side; and

A 2 nd protruding portion protruding from the cover main body portion to the other axial side at a position radially inward of the 1 st protruding portion,

the cover-side conductive member has a contact portion that contacts the case-side conductive member at an end portion on a radially outer side,

the housing cylindrical portion has:

a housing main body portion covering the stator; and

a cylindrical end wall portion protruding from the housing main body portion to one axial side,

the end wall portion is press-fitted to the cover at a groove portion provided between the 1 st projection and the 2 nd projection in a radial direction,

at least a part of the case-side conductive member is located at an end face of one side in the axial direction of the end wall portion,

the contact portion is exposed to the outside of the cover main body portion at the groove portion,

the case-side conduction member and the cover-side conduction member are brought into contact by being sandwiched between the end wall portion and the cover main body portion.

19. The motor of claim 18, wherein the motor is configured to control the motor,

the cover-side conduction member has:

a mounting portion mounted to the one-side bearing housing portion at a radially inner end portion; and

and an extension portion connecting the contact portion and the mounting portion.

20. The motor of claim 18, wherein the motor is configured to control the motor,

the cover-side conduction member is in contact with the case-side conduction member at a surface on the other side in the axial direction of the cover main body portion.

21. The motor of claim 18, wherein the motor is configured to control the motor,

at least a part of the shell-side conduction member is located on an inner peripheral surface, an outer peripheral surface, or an end surface on one side in the axial direction of the shell cylindrical portion,

the case-side conduction member and the cover-side conduction member are brought into contact by being sandwiched between an end portion of the case cylindrical portion on one side in the axial direction and the cover main body portion.

22. The motor of claim 19, wherein the motor is configured to control the motor,

at least a part of the extension portion is embedded in the cover main body portion,

the contact portion is exposed to the outside of the cover main body portion.