WO2018051773A1

WO2018051773A1 - Motor

Info

Publication number: WO2018051773A1
Application number: PCT/JP2017/030731
Authority: WO
Inventors: 康晶中原; 貴之右田; 久嗣藤原; 豪志中村
Original assignee: 日本電産株式会社
Priority date: 2016-09-16
Filing date: 2017-08-28
Publication date: 2018-03-22
Also published as: CN109496387A; JPWO2018051773A1

Abstract

Provided is a motor having: a rotor that has a shaft extending along the center axis; a stator facing the rotor in the radial direction; a cylindrical housing for holding the stator therein, the housing having a first opening at one axial end; a position detection sensor for detecting the rotation position of the rotor, the position detection sensor being accommodated in the housing; and a sensor connection unit electrically connected to the position detection sensor. The housing has an accommodating part in which at least the position detection sensor is accommodated, and a second opening penetrating the accommodating part and the outer surface of the housing. At least a part of the sensor connection unit is positioned in the second opening.

Description

motor

The present disclosure relates to a motor.

In general, in a brushless motor, the rotational position of a rotor is detected, and based on the detected rotor rotational position, a stator side coil (stator coil) is sequentially excited to rotationally drive the rotor. For detecting the rotational position of the rotor, a resolver is often used because it is strong in high temperature and vibration environments, and has a simple structure and is not easily damaged (for example, Patent Document 1). *

The motor described in Patent Document 1 is an inner rotor type brushless motor in which a stator is disposed on the outside and a rotor is disposed on the inside. The stator has a bottomed cylindrical case. The case is formed in a bottomed cylindrical shape with iron or the like. A bracket is attached to the opening of the case. The rotor has a rotor shaft. A magnet holder is externally attached to the rotor shaft. A magnet is arrange | positioned at the outer periphery of a rotor core in the form hold | maintained at a magnet holder. *

A resolver rotor, which is a rotor rotation position detecting means, is attached to the end of the magnet holder. The resolver stator is press-fitted into a metal resolver holder and fixed to the bracket holder unit. The resolver holder is fixed inside the bracket.

JP 2008-79470 A

If the resolver can be arranged near the opening of the case as in the brushless motor described in Patent Document 1, the harness can be easily processed. However, depending on the motor mounting position, conditions, etc., the resolver may have to be arranged near the bottom of the bottomed cylindrical case. In this case, the sensor harness for transmitting the signal from the resolver must be wired inside the case, and the structure of the motor becomes complicated, and it takes time and labor to manufacture the motor. In addition, a high level of technology may be required for manufacturing the motor. *

Therefore, an embodiment of the present disclosure provides a motor having a simple configuration and capable of arranging a position detection sensor for detecting the position of the rotor and a sensor connection unit connected to the sensor.

An exemplary motor of the present disclosure includes a rotor having a shaft extending along a central axis, a stator radially opposed to the rotor, the stator held therein, and a first end at one axial end. A cylindrical housing having an opening; a position detection sensor that is housed in the housing and detects the rotational position of the rotor; and a sensor connection portion that is electrically connected to the position detection sensor. The housing includes a housing portion in which at least the position detection sensor is housed, and a second opening that penetrates the housing portion and an outer surface of the housing, and at least a part of the sensor connection portion. Is located in the second opening.

According to the exemplary embodiment of the present disclosure, it is possible to provide a motor having a simple configuration and capable of arranging a position detection sensor for detecting the position of the rotor and a sensor connection unit connected to the sensor.

FIG. 1 is a perspective view of the motor according to the first embodiment. FIG. 2 is an exploded perspective view showing the components of the motor shown in FIG. 1 in an exploded manner. FIG. 3 is a plan view showing the first bus bar. FIG. 4 is a perspective view of the sensor unit as viewed from above. FIG. 5 is a perspective view of the sensor unit as viewed from below. FIG. 6 is a perspective view of the resolver stator attached to the sensor cover as viewed from above. FIG. 7 is a plan view showing accommodation of the sensor unit in the housing. FIG. 8 is a plan view of the housing to which the sensor unit is attached. FIG. 9 is a diagram illustrating attachment of the stator. FIG. 10 is a diagram illustrating a state in which the first bus bar and the second bus bar are connected.

Hereinafter, a motor according to an exemplary embodiment of the present disclosure will be described with reference to the drawings. The scope of the present disclosure is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical idea of the present disclosure. In the following drawings, in order to make each configuration easy to understand, the actual structure may be different from the scale, number, or the like in each structure. *

In the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z-axis direction is a direction parallel to the axial direction of the central axis C1 of the housing 3 shown in FIG. The Y-axis direction is a direction orthogonal to the Z-axis direction. The X-axis direction is a direction orthogonal to both the Y-axis direction and the Z-axis direction. *

In the state shown in FIG. 1, the Z-axis is defined as the upper side (+ Z side) and the lower side as the negative side (−Z side). The positive side (+ Z side) in the Z-axis direction is called “one side”, and the negative side (−Z side) in the Z-axis direction is called “the other side”. The one side and the other side are simply names used for explanation, and do not limit the actual positional relationship and direction. Unless otherwise specified, the direction parallel to the central axis C1 (Z-axis direction) is simply referred to as “axial direction”, the radial direction centered on the central axis C1 is simply referred to as “radial direction”, and the central axis C1 is the center. The direction along the arc, that is, the circumferential direction of the central axis C1 is simply referred to as “circumferential direction”. *

<1. About motor>

<1.1 Outline of motor configuration>

A schematic configuration of the motor according to the first exemplary embodiment of the present disclosure will be described. FIG. 1 is a perspective view of a motor according to a first embodiment of the present disclosure. FIG. 2 is an exploded perspective view showing the components of the motor shown in FIG. 1 in an exploded manner.

As shown in FIGS. 1 and 2, the motor A according to the present embodiment includes a rotor 1, a stator 2, a housing 3, a first bearing 41, a second bearing 42, a sensor unit 5, and a control board. Bd. *

<1.2 Rotor>

The rotor 1 includes a shaft 11, a rotor core 12, and a rotor magnet 13.

<1.2.1 Shaft>

The shaft 11 has a cylindrical shape extending in the axial direction (Z-axis direction). Although details will be described later, the shaft 11 is rotatably supported by the housing 3 via the first bearing 41 and the second bearing 42. That is, the rotor 1 has a shaft 11 extending along the central axis. The shaft 11 may be a hollow member.

An end 111 on the other axial side of the shaft 11 passes through a through-hole provided in a bottom 313 (described later) provided on the other side of the housing 3 and is exposed to the outside of the housing 3. A rotating body rotated by the motor A is attached to the end 111 on the other axial side of the shaft 11. In addition, as a to-be-rotated body, a gearwheel, a pump, a fan, a compressor etc. can be mentioned, for example, It is not limited to these. As shown in FIG. 2, the end portion 111 on the other axial side of the shaft 11 has a configuration including a plurality of convex portions that protrude radially outward from the outer peripheral surface and extend in the axial direction. Thereby, the shift | offset | difference of the rotation direction of the to-be-rotated body attached to the shaft 11 is suppressed. *

Note that the shape of the end portion 111 is not limited to the above-described shape. For example, a part of a cylinder may be cut out to form a plane parallel to the central axis C1, or a cross section cut by a plane orthogonal to the central axis C1 may have a shape other than a circle (for example, a triangular shape or a square shape). Shape, hexagonal shape), elliptical shape, and the like. Furthermore, the outer peripheral surface may have a cylindrical shape with irregularities. When the shaft 11 rotates, a shape that can suppress the circumferential displacement between the rotated body and the end 111 can be widely employed. *

<1.2.2 Rotor core>

The rotor core 12 is a laminated body in which a plurality of electromagnetic steel plates are laminated and fixed in the axial direction. The rotor core 12 is fixed to the shaft 11. The rotor core 12 surrounds the shaft 11 in the circumferential direction. The shaft 11 and the rotor core 12 have the same center axis.

<1.2.3 Rotor magnet>

The rotor magnets 13 are arranged side by side in the circumferential direction. The rotor magnet 13 is fixed to the rotor core 12. In the rotor 1, the rotor magnet 13 is fixed to the rotor core 12 with resin. The rotor core 12 and the rotor magnet rotate together with the shaft 11. The fixing of the rotor magnet 13 to the rotor core 12 is not limited to resin. The rotor magnet 13 may be fixed to the rotor core 12 via a holding member or the like, and the fixing means is not particularly limited.

<1.3 Stator>

The stator 2 faces the rotor 1 in the radial direction. The center axis of the stator 2 and the rotor 1 coincides. That is, the stator 2 surrounds the outer side of the rotor 1 in the radial direction. The stator 2 includes a stator core 21, a plurality of coils 22, a first bus bar 23, and a second bus bar 24.

<1.3.1 Stator core>

The stator core 21 is a laminated body in which a plurality of electromagnetic steel plates are laminated and fixed in the axial direction. The stator core 21 has an annular core back (not shown) and a plurality of teeth (not shown) extending radially inward from the core back (not shown). The teeth are arranged in the circumferential direction on the inner surface of the core back. At least teeth (not shown) of the stator core 21 are covered with an insulator (not shown). The insulator is formed of a material having electrical insulation properties such as synthetic resin, enamel, rubber, and the like. In addition, the electromagnetic steel plate which comprises the stator core 21 and the electromagnetic steel plate which comprises the rotor core 12 can be manufactured by punching out one workpiece by press work.

<1.3.2 Coil>

The coil 22 is configured by winding a conducting wire 221 around the outer periphery of an insulator 23 that covers the outer surface of the stator core 21. A part of the conducting wire 221 is drawn from the coil 22. The conducting wire 221 protrudes in the axial direction from the end portion on the other axial side of the stator 2. The stator core 21 is excited by supplying electric power to the coil 22 via the conducting wire 221. For example, in the present embodiment, the motor A is a three-phase motor having a U phase, a V phase, and a W phase. Each coil 22 of the motor A belongs to one of three phases (U, V, W). Each phase is supplied with, for example, a sinusoidal current with a phase shift. Therefore, the number of conducting wires 221 is the number that can supply current to each of the three phases (here, two lines, six lines). That is, in the present embodiment, there are two sets of three conducting wires that constitute the U phase, the V phase, and the W phase.

<1.3.3 bus bar>

In the motor A, electric power from an external power source (not shown) is supplied to the coil 22 via the bus bar. The bus bar includes a first bus bar 23 and a second bus bar 24. The first bus bar 23 is fixed to the other axial side of the stator core 21. The first bus bar 23 and the second bus bar 24 have conductivity and are separable. In the present embodiment, the first bus bar 23 and the second bus bar 24 are made of metal.

FIG. 3 is a plan view showing the first bus bar. As shown in FIG. 3, the first bus bar 23 includes an annular portion 231, a conductor connection terminal 232, and a first bus bar connection portion 233. The annular portion 231 has a through-hole penetrating in the axial direction at the center. When the stator 2 is disposed facing the radial direction of the rotor 1, the shaft 11 of the rotor 1 passes through the through hole of the annular portion 231.

The conductive wire connection terminal 232 is connected to each of the three-phase conductive wires 221. Therefore, the number of conducting wire connection terminals 232 is the same as the number of conducting wires 221. The conducting wire connection terminal 232 has a fixed end portion 234 that is folded back in the circumferential direction of the annular portion 231 at the end on the radial front end side. The first bus bar 23 is fixed to the end portion on the other side in the axial direction of the stator core 21, so that the conductive wire 221 is surrounded by the fixed end portion 234 of the corresponding conductive wire connection terminal 232. When the fixed end portion 234 sandwiches a part of the conducting wire 221, the conducting wire 221 and the fixed end portion 234, that is, the conducting wire 221 and the conducting wire connection terminal 232 are electrically connected. In other words, the first bus bar 23 is connected to the conductive wire 221 extending from the plurality of coils 22.

Electric power (current) supplied from an external power supply (not shown) is supplied to each of the three-phase conductors 221 via the first bus bar connection portion 233. Therefore, the first bus bar 23 has three first bus bar connection portions 233. Each of the first bus bar connection portions 233 is electrically connected to the corresponding conductor connection terminal 232. Each of the first bus bar connection portions 233 is a plate member and has a screw hole through which a bolt Bt of a fixture described later passes. *

As shown in FIG. 2, the second bus bar 24 is fixed to a holding portion 55 described later of the sensor unit 5. That is, the second bus bar 24 is held by the holding unit 55. The second bus bar 24 is connected to an external power source. The second bus bar 24 supplies power to each of the three-phase coils 22 from an external power source. The motor A has three second bus bars 24. Each second bus bar 24 includes an external connection terminal 241 and a second bus bar connection part 242. The external connection terminal 241 is connected to an external power source. In the case of the motor A of the present embodiment, the motor A is connected to a power supply circuit provided on the control board Bd outside the housing 3. The external connection terminal 241 is a long plate member and has conductivity. *

The second bus bar connecting portion 242 is a plate member and has a screw hole through which the bolt Bt passes in the center. The external connection terminal 241 and the second bus bar connection portion 242 are continuously formed of the same member. The first bus bar connection portion 233 and the second bus bar connection portion 242 are overlapped in the axial direction of the screw hole, and fixed with bolts Bt and nuts Nt that are fixtures. That is, the first bus bar 23 and the second bus bar 24 are fixed by the fixture. The fixture is not limited to the bolt Bt and the nut Nt. The fixture may be, for example, a rivet, adhesion with a conductive adhesive, or the like. As the fixture, members, structures, and configurations that can fix the first bus bar 23 and the second bus bar 24 can be widely used. Thereby, the first bus bar 23 and the second bus bar 24 are electrically connected. Details of the second bus bar 24 and the holding unit 55 of the sensor unit 5 will be described later. *

<1.4 Housing configuration>

The housing 3 has a cylindrical shape and includes a cover portion 32 and a substrate placement portion 33.

<1.4.1 Housing body>

The housing 3 has a cylindrical shape extending along the central axis C1. The housing 3 serves as an exterior housing that protects the inside of the motor A. Therefore, in this embodiment, the housing 3 is made of metal having a strength for protecting the inside. In addition, when it has sufficient intensity | strength as an exterior housing | casing, the housing 3 may be comprised with materials other than a metal.

The housing 3 includes a first opening 311, a second opening 312, a bottom 313, a housing part 314, a cover fixing part 315, and a bearing fixing part 316. The housing 3 holds the stator 2 inside. The housing 3 accommodates the rotor 1 and the sensor unit 5. *

<1.4.1.1 First Opening>

The first opening 311 is located on the one axial side of the housing 3. That is, the housing 3 has a first opening at the end on one side in the axial direction. The bottom 313 is located on the other axial side of the housing 3. The stator 2 is inserted from the first opening 311. The stator 2 is fixed inside the housing 3 by press-fitting the outer peripheral surface of the stator core 21 into the inner peripheral surface of the housing 3. Thereby, the center axis | shaft (C1) of the stator 2 and the housing 3 corresponds. That is, the housing 3 holds the stator inside.

In this embodiment, the stator core 21 is fixed to the housing 3 of the stator 2 by press-fitting the stator core 21 into the housing 3. However, the fixing method of the stator 2 to the housing 3 may be other fixing methods such as shrink fitting, and a fixing method that can fix the stator 2 to the inside of the housing 3 can be widely adopted. It is not limited. The housing 3 has a plurality (four in this case) of cover fixing portions 315 projecting radially outward from the outer peripheral surface at one end in the axial direction. The cover fixing part 315 has a female screw. When the cover portion 32 is covered and fixed to the fixing portion, the screw Sc is screwed into the female screw. *

<1.4.1.2 Bottom>

The bottom portion 313 closes the other axial side of the housing 3. A central portion in the radial direction of the bottom portion 313 has a through hole penetrating from the inside to the outside in the axial direction. The bottom portion 313 is provided with a bearing fixing portion 316 that fixes the first bearing 41. In the housing 3, the axially one side portion of the through hole provided in the bottom portion 313 is a bearing fixing portion 316. The first bearing 41 is fixed to the bearing fixing portion 316. One end of the shaft 11 in the axial direction protrudes outside the housing 3.

<1.4.1.3 Container>

The accommodating portion 314 is a space that is provided inside the housing 3 and accommodates the sensor unit 5. The accommodating portion 314 is located adjacent to one axial side of the bottom portion 313 of the housing 3. The accommodating portion 314 is located between the bottom portion 313 and the stator 2. When the sensor unit 5 is stored in the storage unit 314, the holding unit 55 of the sensor unit 5 is fixed to the bottom 313. The holding part 55 is fixed with a screw, for example. By accommodating the holding part 55 in the accommodating part 314, at least a position detection sensor 51 described later of the sensor unit 5 is accommodated in the accommodating part 314.

<1.4.1.4 Second opening>

The second opening 312 passes through the housing 314 and the outer surface of the housing 3. The second opening 312 is a through hole that penetrates the housing 3 in the radial direction. The second opening 312 has a shape and size into which the sensor unit 5 can be inserted. The sensor unit 5 is inserted into the storage unit 314, and the holding unit 55 is fixed. Thereby, the sensor connection portion 53 of the sensor unit 5 and the external connection terminal 241 of the second bus bar 24 are exposed from the second opening 312 to the outside of the housing 3.

<1.4.2 Cover part>

In the present embodiment, the cover part 32 has a cylindrical shape. The cover part 32 is fitted into the first opening 311 of the housing 3. The cover part 32 closes the first opening 311. At this time, the cover portion 32 can reinforce the end portion on the one axial side of the housing 3. Therefore, it is desirable that the cover part 32 is made of metal, for example. In addition, when it has intensity | strength sufficient for reinforcement, the material of the cover part 32 is not limited to a metal, Another material may be used.

The cover part 32 has a fixing part 321 and a bearing fixing part 322. The fixing portion 321 protrudes radially outward from an end portion on one axial side of the cover portion 32. The fixed part 321 has a through hole penetrating in the axial direction. The number of fixing parts 321 is the same as the number of cover fixing parts 315. The fixing portion 321 and the cover fixing portion 315 are overlapped in the axial direction, the screw Sc is passed through the through hole of the fixing portion 321, and the screw Sc is screwed into the female screw of the cover fixing portion 315. Accordingly, the cover portion 32 closes the first opening 311 and is fixed to the housing 3. *

The bearing fixing portion 322 is provided at the central portion on the other axial side of the cover portion 32. The bearing fixing portion 322 has an inner peripheral surface (not shown) coaxial with the central axis. The second bearing 42 is fixed to the bearing fixing portion 322. *

<1.4.3 Substrate placement section>

The rotation of the motor A is controlled by the control board Bd. The control board Bd supplies predetermined power to the coils 22 of each phase of the stator 2 based on information on the rotation angle (position) of the rotor 1 from the sensor unit 5. As shown in FIG. 1, the control board Bd is attached to the board placement unit 33. The substrate placement portion 33 is provided on the outer surface of the housing 3. The substrate placement part 33 has a wall part 331 surrounding at least a part of the outer periphery. That is, the housing 3 has a substrate placement portion 33 for placing the control board Bd on the outer surface. In the motor A, the control board Bd is arranged in a part surrounded by the wall part 331 of the board arrangement part 33. The board placement portion 33 is adjacent to the second opening 312 in the radial direction of the housing 3.

Therefore, the control board Bd covers the outside of the second opening 312 by arranging the control board Bd on the board placement portion 33. A connector (not shown) connected to the external connection terminal 241 and a connector (not shown) connected to the conduction portion 531 are provided on the outer surface side of the second opening 312 of the control board Bd and in the radial direction of the housing 3. Is implemented. Thus, the external connection terminal 241 and the sensor conduction part 531 can be directly connected to the control board Bd. *

<1.5 Bearing>

The shaft 11 is rotatably supported by the first bearing 41 on one side of the rotor core 12 and the second bearing 42 on the other side in the axial direction. That is, the rotor 1 is rotatably supported by the first bearing 41 and the second bearing 42. In other words, the end of one side of the shaft 11 in the axial direction is rotatably supported by the first bearing 41. The end of the shaft 11 on the other side in the axial direction is rotatably supported by the second bearing 42.

<1.5.1 First bearing>

In the present embodiment, the first bearing 41 is a rolling bearing (ball bearing), and includes an outer ring, an inner ring, and a plurality of balls. The outer ring and the inner ring are arranged coaxially, and a plurality of balls are arranged in the circumferential direction at a portion between the outer ring and the inner ring. In addition, the 1st bearing 41 may be the structure using the roller which is a cylindrical rotary body instead of a ball | bowl. The first bearing 41 is not limited to a ball bearing, and other types of bearings such as an oil-impregnated bearing may be used.

The outer ring of the first bearing 41 is press-fitted into the inner peripheral surface of the bearing fixing portion 316. As a result, the first bearing 41 is fixed to the bearing fixing portion 316. The shaft 11 is press-fitted into the inner ring of the first bearing 41. As a result, the shaft 11 is fixed to the bearing 41. The shaft 11 is attached to the housing 3 via the first bearing 41. *

The shaft 11 is rotatably supported by the first bearing 41 at a portion away from the end 111 on the other side in the axial direction by a certain length. The shaft 11 is rotatably supported by the housing 3 via the first bearing. The end portion 111 on the other side in the axial direction of the shaft 11 is exposed to the outside of the housing 3 through the through hole of the bottom portion 313. *

<1.5.2 Second bearing>

In the present embodiment, the second bearing 42 is a so-called ball bearing having the same configuration as the first bearing 41. The second bearing 42 has an outer ring, an inner ring, and a plurality of balls. In addition, the 2nd bearing 42 may be the structure using the roller which is a cylindrical rotary body instead of a ball | bowl. The second bearing 42 may be another type of bearing such as an oil-impregnated bearing. The second bearing 42 may be a different type of bearing from the first bearing 41.

The outer ring of the second bearing 42 is press-fitted into the inner peripheral surface of the bearing fixing portion 322 of the cover portion 32. As a result, the second bearing 42 is fixed to the bearing fixing portion 322. The cover part 32 closes the first opening 311 and is fixed to the housing 3. At this time, the second bearing 42 fixed to the bearing fixing portion 322 of the cover portion 32 is coaxial with the housing 3 (center axis C1). The end of the shaft 11 on the other side in the axial direction is press-fitted into the inner ring of the second bearing 42. Thereby, the shaft 11 is rotatably supported by the second bearing 42. *

<1.6 Sensor unit>

Next, the sensor unit 5 will be described with reference to the drawings. FIG. 4 is a perspective view of the sensor unit as viewed from above. FIG. 5 is a perspective view of the sensor unit as viewed from below. FIG. 6 is a perspective view of the resolver stator attached to the sensor cover as viewed from above.

In the motor A, a position detection sensor 51 that detects the rotational position of the shaft 11, that is, the rotational position of the rotor 1, is accommodated inside the housing 3. The motor A has a sensor unit 5 including a position detection sensor 51. The motor A of the present embodiment is for driving a pump that maintains the hydraulic pressure in, for example, a hydraulic device. In such an application, the motor A is driven at a relatively low speed. Therefore, in the motor A according to the present embodiment, the position detection sensor 51 that detects the rotational position of the rotor 1 is a resolver. The resolver can detect the rotational position of the rotor 1 in a relatively low speed region. The resolver has a resolver stator 511 and a resolver rotor 512. *

In the present embodiment, the sensor unit 5 includes a resolver stator 511, a resolver rotor 512, a sensor connection part 53, a sensor cover 54, and a holding part 55. The position detection sensor 51 that detects the rotation angle of the rotor 1 is not limited to a resolver. The position detection sensor may be a sensor including a hall element. A wide variety of sensors that can detect the rotation angle of the rotor 1 can be used as the position detection sensor. *

<1.6.1 Resolver stator>

The resolver stator 511 is annular. The resolver stator 511 has coils arranged in the circumferential direction. The resolver stator 511 is located on the radially outer side of the resolver rotor 512. The resolver stator 511 is attached to the housing 3 via the sensor cover 54 and the holding portion 55.

<1.6.2 Resolver rotor>

The resolver rotor 512 is fixed to the shaft 11. The resolver rotor 512 is disposed on the radially inner side of the resolver stator 511. The position detection sensor 51 detects the rotation angle of the shaft 11 with the resolver stator 511 and the resolver rotor 512. The resolver rotor 512 is accommodated in the housing 3. That is, at least the position detection sensor 51 is accommodated in the housing 3.

<1.6.3 Sensor connection part>

The sensor connection unit 53 is electrically connected to the resolver stator 511. That is, the sensor connection unit 53 is electrically connected to the position detection sensor 51. The sensor connection unit 53 connects the resolver stator 511 and the control board Bd. The sensor connection portion 53 is a metal terminal, and a plurality of sensor connection portions 53 are provided. The sensor connection unit 53 is a terminal that transmits a signal generated by the resolver stator 511 to the outside. The plurality of sensor connection portions 53 are arranged in parallel to each other and are fixed independently of each other. In the present embodiment, the position detection sensor 51 and the sensor connection unit 53 are held by the holding unit 55. The front end portion of the sensor connection portion 53 is connected to the conduction portion 531. That is, the sensor connection unit 53 held by the holding unit 55 includes a conduction unit 531 that is electrically connected to the position detection sensor 51. The leading end portion of the conducting portion 531 extends outside the outer peripheral surface of the holding portion 55 opposite to the curved surface portion 554 described later.

<1.6.4 Sensor cover>

The sensor cover 54 covers the resolver stator 511. That is, the position detection sensor 51 has a sensor cover 54. The sensor cover 54 includes a cylinder portion 541 and a flange portion 542. A resolver stator 511 is press-fitted into the cylindrical portion 541. Thereby, the resolver stator 511 is fixed to the sensor cover 54. The cylinder part 541 has an opening for pulling out the sensor connection part 53 to the outside when the resolver stator 511 is fixed inside. The flange portion 542 extends radially outward from the other axial end of the cylindrical portion 541. The flange portion 542 is used as a fixture to the holding portion 55.

<1.6.5 holding part>

The holding part 55 has a resolver mounting hole 551, a bus bar fixing part 552, and a bus bar hole 553. The holding part 55 has a cylindrical curved surface part 554 on a part of the outer peripheral surface. A part of the holding part 55 is accommodated in the accommodating part 314. The curved surface portion 554 comes into contact with the inner peripheral surface of the housing 3 when the holding portion 55 is accommodated in the accommodating portion 314. The resolver mounting hole 551 is a through hole extending in a cylindrical shape coaxial with the curved surface portion 554. That is, the resolver mounting hole 551 is a through hole having a cylindrical inner side surface that is coaxial with the curved surface portion 554. A resolver stator 511 fixed to the sensor cover 54 is fixed to the resolver mounting hole 551. In this embodiment, the resolver stator 511 is fixed by fixing the flange portion 542 of the sensor cover 54 to the holding portion 55 with screws. The fixing of the sensor cover 54 to the holding portion 55 is not limited to a screw. For fixing the sensor cover 54 to the holding portion 55, for example, other fixing methods such as welding and press-fitting can be employed.

When the resolver stator 511 is attached to the resolver attachment hole 551, the sensor connection portion 53 is held by the holding portion 55. That is, the holding unit 55 holds the position detection sensor 51 and the sensor connection unit 53. The holding portion 55 is provided with a recess 550. When the resolver stator 511 is attached to the resolver attachment hole 551, the sensor connection portion 53 fits into the recess 550. Thereby, the sensor connecting portion 53 is protected by the holding portion 55. As a result, the sensor connection portion 53 can be prevented from being bent or bent. *

The bus bar fixing portion 552 of the holding portion 55 is connected to the bus bar hole 553. The bus bar fixing portion 552 opens on one side in the axial direction. The second bus bar connection part 242 of the second bus bar 24 is fixed to the bus bar mounting hole 552. When the second bus bar connection portion 242 and the nut Nt are attached to the bus bar attachment hole 552, the central axes coincide with each other. This central axis extends in the direction in which the external connection terminal 241 extends, here, parallel to the Y axis. The second bus bar connection part 242 is fixed to the bus bar fixing part 552. In the present embodiment, the second bus bar connection portion 242 is fixed by, for example, welding, but is not limited thereto. Another method may be used as a method of fixing the second bus bar connection unit 242 to the bus bar fixing unit 552. *

The bus bar hole 553 penetrates from the bus bar fixing part 552 to the end surface of the holding part 55 opposite to the curved surface part 554. That is, the bus bar hole 553 extends in the Y-axis direction. An external connection terminal 241 of the second bus bar 24 is disposed inside the bus bar hole 553. The external connection terminal 241 is exposed to the outside of the holding unit 55. The external connection terminal 241 protrudes outward toward the opposite side of the curved surface portion 554. The holding portion 55 has a spacer 555 extending on the other axial end side on the end surface on the other axial side. When the holding part 55 is accommodated in the accommodating part 314, the spacer 555 contacts the bottom part 313. *

<2. Assembling the motor>

The assembly procedure of the motor A according to this embodiment will be described with reference to the drawings. FIG. 7 is a plan view showing accommodation of the sensor unit in the housing. FIG. 8 is a plan view of the housing to which the sensor unit is attached. FIG. 9 is a diagram illustrating attachment of the stator. FIG. 10 is a diagram illustrating a state in which the first bus bar and the second bus bar are connected. 8 to 10 show the operation inside the housing 3, and the illustration of the housing 3 itself is omitted.

First, the sensor unit 5 is manufactured. After the resolver stator 511 is attached to the sensor cover 54, the resolver stator 511 is attached to the resolver attachment hole 551 of the holding portion 55 together with the sensor cover 54. The resolver stator 511 is fixed to the holding portion 55 by screwing the sensor cover 54 to the holding portion 55. At this time, the center axis of the resolver stator 511 and the resolver mounting hole 551 coincide. When the resolver stator 511 is attached to the resolver attachment hole 551, the sensor connection part 53 or the conduction part 531 protrudes outside the holding part 55. The sensor connection portion 53 or the conduction portion 531 extends outward from the outer peripheral surface on the side opposite to the curved surface portion 554. *

A second bus bar connection part 242 of the second bus bar 24 is arranged in the bus bar fixing part 552 of the holding part 55. At this time, the tip of the external connection terminal 241 of the second bus bar 24 protrudes outside the holding portion 55 through the bus bar hole 553. The external connection terminal 241 protrudes from the surface on the opposite side to the curved surface portion 554 of the outer peripheral surface of the holding portion 55 (see FIGS. 4, 5, 6, etc.). That is, in the sensor unit 5, the resolver stator 511 is attached to the resolver attachment hole 551, and the second bus bar connection part 242 of the second bus bar 24 is fixed to the bus bar fixing part 552. Thereby, the conduction | electrical_connection part 531 and the external connection terminal 241 are extended on the opposite side to the curved surface part 554 of the holding | maintenance part 55, respectively. The leading end of the conducting portion 531 and the leading end of the external connection terminal 241 are located outside the surface of the outer peripheral surface of the holding portion 55 opposite to the curved surface portion 554. *

As shown in FIG. 7, the sensor unit 5 is inserted in the + Y direction into the second opening 312 from the curved surface portion 554 side. The curved surface portion 554 contacts the inner peripheral surface of the housing 3. At this time, the resolver mounting hole 551 of the holding portion 55 is aligned with the inner peripheral surface of the housing 3 and the central axis (C1). That is, the resolver stator 511 attached to the resolver attachment hole 551 has the inner peripheral surface of the housing 3 and the central axis (C1) coincident with each other. The holding portion 55 is fixed to the bottom portion 313 with a screw Sc1 (see FIG. 2). At this time, the spacer 555 contacts the bottom 313. Accordingly, contact between the surface on the other axial side of the holding portion 55 and the first bearing 41 fixed to the bearing fixing portion 316 on one axial side of the through hole provided in the bottom portion 313 is suppressed. *

When the holding portion 55 is fixed to the bottom portion 313, the portion of the holding portion 55 where the bus bar hole 553 is provided is located in the second opening 312. An end of the bus bar hole 553 on the outer wall side is located outside the outer peripheral surface of the housing 3. Further, the external connection terminal 241 and the conducting portion 531 are also located outside the outer peripheral surface of the housing 3 (see FIG. 1). That is, at least a part of the conducting portion 531 is exposed to the outside of the housing 3. In other words, at least a part of the sensor connection portion 53 is located in the second opening 312. *

In the motor A, the housing 3 has a second opening 312 penetrating outside from the housing portion 314 on the side surface in the radial direction. The sensor unit 5 is inserted into the housing part 314 through the second opening 312. Therefore, attachment is easy compared with the case where the sensor unit 5 is inserted from the 1st opening part 311 which is an edge part of the axial direction one side. Further, the sensor connection portion 53 and the external connection terminal 241 are exposed to the outside of the housing 3 from the second opening 312. Therefore, it is not necessary to route the wiring inside the housing 3, and accordingly, the structure can be simplified and labor and time for manufacturing can be reduced. Further, the sensor unit 5 is configured to hold the position detection sensor by the holding unit 55. Therefore, even if the size and detection method of the position detection sensor are different, the shape and size of the holding portion 55 may be changed, and the position adjustment of the position detection sensor with respect to the sensor unit 5 is easy. . *

As shown in FIG. 8, the stator 2 is inserted into the housing 3 from the first opening 311 in a state where the sensor unit 5 is housed in the housing 314 from the second opening 312. At this time, the first bus bar 23 is attached to the end portion on the other axial side of the stator core 21. The conductor connection terminals 232 of the first bus bar 23 are connected to the corresponding conductors 221 via the fixed end portions 234, respectively. *

The stator 2 is fixed inside the housing 3 by press-fitting the outer peripheral surface of the stator core 21 into the inner peripheral surface of the housing 3. The force for press-fitting the stator 2 into the housing 3 acts on the stator core 21. Further, the force when press-fitting the stator 2 is unlikely to act on the coil 22 and the first bus bar 23. Accordingly, when the stator 2 is inserted into the housing 3, deformation of the coil 22 and the first bus bar 23 can be suppressed. *

The stator 2 moves to the stator fixing portion 310 on one axial side of the housing portion 314 inside the housing 3. At this time, the first bus bar connection portion 233 is inserted into the bus bar fixing portion 552 of the holding portion 55 accommodated in the accommodation portion 314 from one side in the axial direction. That is, the housing 3 has a stator fixing portion 310 to which the stator 2 is fixed on one side in the axial direction of the housing portion 314. Since the stator 2 is press-fitted into the housing 3, it is difficult to rotate the starter 2 inside the housing 3. Therefore, the stator 2 is preferably inserted from the first opening 311 in a state where the first bus bar connection portion 233 is overlapped with the bus bar fixing portion 552 in the axial direction. *

When the stator 2 moves to the stator fixing portion 310 inside the housing 3, it may have a structure that stops the movement of the stator 2 in the axial direction. For example, the housing 3 may have a convex portion protruding radially inward from the inner peripheral surface and a convex portion extending in the axial direction from the bottom portion 313. Thereby, the movement of the stator 2 in the axial direction can be stopped, and the stator 2 can be prevented from being displaced from the predetermined position on the other side in the axial direction. *

There is also a fixing method in which the stator 2 can be rotated inside the housing 3. When such a fixing method is adopted, when the stator 2 is inserted from the first opening 311, the first bus bar connecting portion 233 and the bus bar fixing portion 552 do not have to overlap in the axial direction. *

When the stator 2 moves to the stator fixing portion 310 inside the housing 3, the first bus bar connection portion 233 is inserted into the bus bar fixing portion 552. At this time, the central axis of the screw hole of the first bus bar connection portion 233 is a direction along the Y axis. On the other hand, the second bus bar connection part 242 and the nut Nt of the second bus bar 24 are fixed to the bus bar fixing part 552. An end of the bus bar hole 553 on the outer wall side is outside the outer peripheral surface of the housing 3. Therefore, the bolt Bt can be inserted into the bus bar fixing portion 552 via the bus bar hole 553 from the outside in the radial direction of the housing 3. *

The bolt Bt is passed through the screw hole of the first bus bar connection part 233 and the screw hole of the second bus bar connection part 242. Screw the tip of the bolt Bt into the nut Nt. Thereby, the 1st bus bar connection part 233 and the 2nd bus bar connection part 242 are electrically connected using bolt Bt and nut Nt. That is, the first bus bar 23 and the second bus bar 24 are electrically connected. In the motor A of the present embodiment, the first bus bar 23 and the second bus bar 24 are connected using the bolts Bt inserted from the side portions of the housing 3. Therefore, the manufacture of the motor A is easy. In addition, since the motor A has the above-described configuration, the space required for mounting in the motor A can be smaller than that of welding or pressure bonding. Thereby, the external shape of the motor A can be made small. *

After the stator 2 and the sensor unit 5 are arranged inside the housing 3, the rotor 1 is inserted from the first opening 311. A rotor core 12 is attached to an intermediate portion of the shaft 11. A resolver rotor 512 is attached to the other side in the axial direction than the rotor core 12 of the shaft 11. *

The rotor 1 is inserted into the first opening 311 from the end 111 on the other axial side of the shaft 11. The end 111 on the other axial side of the shaft 11 passes through a through hole provided in the bottom 313 to the other axial side and is exposed to the outside of the housing 3. The shaft 11 is press-fitted into the inner ring of the first bearing 41 on the other axial side than the rotor core 12. As a result, the shaft 11 is rotatably supported by the housing 3 via the first bearing 41. *

When the shaft 11 is press-fitted into the first bearing 41, the resolver rotor 512 attached to the shaft 11 and the resolver stator 511 accommodated in the accommodating portion 314 are opposed to each other in the radial direction. Accordingly, the position detection sensor 51 that detects the rotational position of the shaft 11 can be operated. That is, the position detection sensor includes a resolver rotor 512 attached to the rotor 1 and a resolver stator 52 that faces the resolver rotor 512 in the radial direction. Similarly, the rotor core 12 faces the stator core 21 fixed inside the housing 3 in the radial direction. That is, the stator 2 faces the rotor 1 in the radial direction. *

After the rotor 1 is disposed inside the housing 3, the cover portion 32 is fitted into the first opening 311. At this time, the second bearing 42 is fixed to the bearing fixing portion 322 of the cover portion 32. When the cover portion 32 is attached to the first opening portion 31, the end portion on one side in the axial direction of the shaft 11 is press-fitted into the inner ring of the first bearing 41. The fixing part 321 of the cover part 32 is arranged so as to overlap the cover fixing part 315 of the housing 3 in the axial direction. The through hole of the fixing portion 321 is penetrated with the screw Sc. The tip of the screw Sc that passes through the through hole is screwed into the female screw hole of the cover fixing portion 315 to fix the cover portion 32 to the housing 3. Thereby, as for the 2nd bearing 42 fixed to the bearing fixing | fixed part 322 of the cover part 32, the inner peripheral surface of the housing 3 and a center axis | shaft (C1) correspond. *

As described above, the first bearing 41 and the second bearing 42 coincide with the housing 3 and the central axis (C1). The shaft 11 is rotatably supported by the first bearing 41 and the second bearing 42. *

Further, the control board Bd is attached to the board placement portion 33 outside the housing 3. The control board Bd is attached so as to cover the radially outer side of the housing 3 of the second opening 312. A connector (not shown) connected to the external connection terminal 241 and a connector (not shown) connected to the conducting portion 531 are formed on the control board Bd at a portion overlapping the outer surface of the second opening 312 and the radial direction of the housing 3. Implemented. The connector connected to the external connection terminal 241 is a part of the power supply circuit, and supplies three-phase (U phase, V phase, W phase) power from the external connection terminal 241. The connector connected to the conducting portion 531 is a part of the control circuit, and sends information on the rotation angle of the rotor 1 to the control circuit. *

As described above, in the motor A according to this embodiment, the housing 3 includes the first opening 311 that opens to one side in the axial direction, the second opening 312 that penetrates from the storage portion to the outside in the radial direction, Have Since the sensor unit 5 can be inserted from the second opening 312, the sensor unit 5 can be easily attached. *

<3. Modified example>

In the embodiment described above, the second bus bar 24 is fixed to the holding unit 55. However, the second bus bar 24 may be attached separately from the holding unit 55. For example, depending on the configuration of the motor A, the bus bar may be disposed on the first opening 311 side. In such a case, the second bus bar 24 is not fixed to the holding portion 55. Alternatively, the second bus bar 24 may be attached to the bus bar fixing portion 552 from the bus bar hole 553 after the holding portion 55 is received and fixed in the receiving portion 314.

In the embodiment described above, the resolver stator 511 is fixed to the sensor cover 54 and then attached to the holding portion 55 to form the sensor unit 5. However, the method for assembling the motor A is not limited to the method described above. For example, with the resolver stator 511 attached to the sensor cover 54, the resolver stator 511 is inserted into the housing portion 314 from the second opening 312, and the sensor cover 54 is fixed inside the housing 3 such as the bottom 313 and the inner peripheral surface of the housing 3. May be. Also in this case, a part of the sensor connecting portion 53 is located in the second opening 312, that is, the sensor connecting portion 53 is exposed to the outside from the second opening 312. Since the resolver stator 511 is protected by the sensor cover 54, it is possible to suppress breakage when the resolver stator 511 is attached. Further, since the holding portion 55 is not inserted from the second opening 312, the second opening 312 can be made small.

Further, the position detection sensor and the sensor connection portion may be inserted from the second opening 312 without being attached to the sensor cover. For example, when the housing portion 314 has a fixing portion that fixes the position detection sensor, the sensor cover and the holding portion can be omitted. *

Although the embodiments of the present disclosure have been described above, the embodiments can be variously modified within the scope of the gist of the present disclosure.

The embodiment of the present disclosure can be used as a motor that drives a pump that maintains hydraulic pressure. In addition, the embodiment of the present disclosure can be used for a power source of various electric apparatuses other than a pump that maintains hydraulic pressure.

A: Motor, 1 ... Rotor, 11 ... Shaft, 12 ... Rotor core, 13 ... Rotor magnet, 2 ... Stator, 21 ... Stator core, 22 ... Coil, 221 ... ..Conducting wire, 23 ... first bus bar, 231 ... annular portion, 232 ... conductor connecting terminal, 233 ... first bus bar connecting portion, 234 ... fixed end, 24 ... first 2 bus bars, 241 ... external connection terminal, 242 ... second bus bar connection part, 3 ... housing, 311 ... first opening part, 312 ... second opening part, 313 ... bottom part 314... Storage portion 315... Cover fixing portion 316... Bearing fixing portion 32... Cover portion 321. Substrate placement portion, 331 ... wall portion, 41 ... first bearing, 42 ... 2 bearings, 5 ... sensor unit, 511 ... resolver stator, 512 ... resolver rotor, 53 ... sensor connection part, 531 ... conduction part, 54 ... sensor cover, 541 ... Tube part, 542 ... Flange part, 55 ... Holding part, 550 ... Recess, 551 ... Resolver mounting hole, 552 ... Bus bar fixing part, 553 ... Bus bar hole, 554 ... Curved part, 555 ... Spacer

Claims

A rotor having a shaft extending along a central axis;

A stator radially opposed to the rotor;

A cylindrical housing that holds the stator inside and has a first opening at one end in the axial direction;

A position detection sensor that is housed in the housing and detects the rotational position of the rotor;

A sensor connection portion electrically connected to the position detection sensor;

Have

The housing is

An accommodating portion in which at least the position detection sensor is accommodated;

A second opening that penetrates the housing and the outer surface of the housing;

Have

At least a part of the sensor connection part is located in the second opening.
The motor according to claim 1, wherein the position detection sensor has a sensor cover.
The position detection sensor is

A resolver rotor attached to the rotor;

A resolver stator radially opposed to the resolver rotor;

The motor according to claim 1, comprising:
The motor according to claim 1, wherein the position detection sensor includes a hall element.
A holding part that holds the position detection sensor and the sensor connection part and is partially housed in the housing part,

The sensor connection portion held by the holding portion includes a conduction portion electrically connected to the position detection sensor,

The motor according to claim 1, wherein at least a part of the conducting portion is exposed to the outside of the housing.
The stator is

A plurality of coils;

A first bus bar connected to a conducting wire extending from the plurality of coils;

A second bus bar connected to an external power source;

Further comprising

The second bus bar is held by the holding unit,

The motor according to claim 5, wherein the first bus bar and the second bus bar are electrically connected.
The motor according to claim 6, wherein the first bus bar and the second bus bar are fixed by a fixture.
The motor according to claim 1, wherein the housing has a stator fixing portion to which the stator is fixed on one side in the axial direction of the housing portion.
The motor according to any one of claims 1 to 8, wherein the housing includes a board placement portion that places a control board on the outer surface.