WO2018198866A1 - Electric motor element, electric motor, and device - Google Patents

Abstract

Provided is an electric motor element including a stator and a rotor having a plurality of magnetic poles. The rotor includes a configuration having a magnetic salient polarity. The configuration having the magnetic salient polarity includes: a plurality of d-axis magnetic flux paths for generating a magnet torque among the rotational torque components generated by the rotating magnetic field from the stator; and a plurality of q-axis magnetic flux paths for generating a reluctance torque among the rotational torque components. A part of each of the d-axis magnetic flux paths includes a bond magnet portion, and a part of each of the q-axis magnetic flux paths includes the bond magnet portion or an adjacent portion that is different from the bond magnet portion and makes contact with the bond magnet portion. When the extended line of the line connecting the center of the plurality of magnetic poles and the center of the rotation axis of the rotor is defined as a d-axis and the line shifted by an electrical angle of 90 degrees with respect to the d-axis and passing through the center of the rotation axis of the rotor is defined as a q-axis, a magnetization direction of a bond magnet portion main section that is a main section of the bond magnet portion positioned at a site adjacent to the q-axis is one angle among the four angles at the intersection point formed by a magnetization direction virtual extended line in the magnetization direction and the q-axis. The one angle is an angle portion sandwiched by a q-axis segment between the intersection point and the outer circumference of the rotor among the segments included in the q-axis and the magnetization direction virtual extended line. The angle of the angle portion is 30 degrees to 150 degrees.

Description

Motor elements, motors, equipment

The present invention relates to an electric motor element and an electric motor and an apparatus including the electric motor element.

Conventionally, electromagnetic steel sheets are frequently used for stator yokes (stator magnetic cores) of stators of electric motor elements mounted on electric devices and the like. The electromagnetic steel sheet used for this stator yoke (stator magnetic core) has a characteristic of low magnetic loss in order to increase the efficiency of the motor element. For example, a magnetic steel sheet coats the surface of a magnetic steel sheet, electrically insulates the magnetic steel sheets, and suppresses an increase in eddy current. Furthermore, the generation of eddy current is similarly suppressed by increasing the Si content of the electromagnetic steel sheet and increasing the electrical resistance of the electromagnetic steel sheet itself. For example, among non-oriented electrical steel sheets used for electric motors, about 2 wt% to 3 wt% Si is added to high grade electrical steel sheets, and about 1 wt% Si is added to medium to low grade electrical steel sheets. In recent years, electrical steel sheets in which the additive amount of Si is increased from about 6 wt% to about 7 wt% have been developed.

On the other hand, electromagnetic steel plates are also frequently used for the rotor yoke (rotor core) on the rotor side having the permanent magnet portion. When electromagnetic steel sheets are used for stators and rotors, both stators and rotors are of the same type and material, mainly from the viewpoint of mass production in industrial production and management from industrial production. Most cases use steel plates.

As long as there is no malfunction in the operating state of the rotational drive of the motor element, there is no particular problem even if the stator and the rotor are both magnetic steel sheets of the same product type and material.

However, when the rotating operation of the electric motor element stops for some reason (hereinafter, the mode in which the rotating operation stops is expressed as a motor lock), the rotating magnetic field from the stator is stopped with the rotor stopped. May be applied to the rotor as a reverse magnetic field. This reverse magnetic field may cause demagnetization of the permanent magnet portion mounted on the rotor. By performing a demagnetization test that simulates the situation when the motor is locked, it is also possible to confirm the state of the malfunction phenomenon caused by the demagnetization of the permanent magnet portion mounted on the rotor.

One factor that causes demagnetization of the permanent magnet due to the reverse magnetic field when the motor is locked is considered as follows. That is, when the motor is locked, the rotor that has stopped rotating is positioned in the rotating magnetic field from the stator. The permanent magnet portion of the rotor is also located in the rotating magnetic field. A state in which this rotating magnetic field acts in the direction of demagnetizing the permanent magnet portion of the rotor can occur. On the other hand, the electrical steel sheet used for the rotor magnetic core has an insulating coating and contains a large amount of Si. Therefore, the electrical resistivity of the electrical steel sheet is larger than that of copper or the like. The eddy current of the electrical steel sheet generated by electromagnetic induction is slight. Therefore, the eddy current generated in the electromagnetic steel sheet of the rotor by the rotating magnetic field from the stator is small. The rotating magnetic field from the stator reaches the permanent magnet portion located inside the rotor without being canceled by the magnetic field due to the eddy current. The rotating magnetic field may also occur as a strong reverse magnetic field that demagnetizes the permanent magnet portion. For example, as shown in FIG. 10, a reverse magnetic field (arrow 16) flows from the stator into the rotor 2 in a substantial radial direction. For this reason, when the magnetization direction 10a of the bond magnet part 10 located in the outer peripheral part of the rotor 2 is opposite to the reverse magnetic field (substantially opposite to the direction of the arrow 16), the bond magnet part 10 is demagnetized. Sometimes. If the demagnetized bond magnet unit 10 is not magnetized again, it does not recover to the original residual magnetic flux density, and the amount of magnetic flux from the bond magnet unit 10 remains reduced by demagnetization. Therefore, the motor element exhibits a characteristic that is deteriorated from the initial characteristic.

Thus, the Si content applied to reduce the loss due to the eddy current of the electrical steel sheet is relatively large, and the insulating coating that electrically insulates the electrical steel sheets from each other Since the generation is suppressed, the phenomenon of demagnetization of the permanent magnet portion due to the reverse magnetic field when the motor is locked cannot be suppressed.

In general, permanent magnets of motors and motor elements are equipped with rare-earth sintered magnets with high coercive force, etc. from the viewpoint of the technical idea of increasing the safety factor. In many cases, the demagnetization of the permanent magnet portion is suppressed. However, economics are an issue.

For example, when a high coercive force magnet such as a NdFeB sintered magnet is used for the permanent magnet portion mounted on the rotor, the high coercive force acts effectively. Therefore, even when the motor lock occurs, demagnetization of the permanent magnet portion due to the reverse magnetic field is rare. That is, a high-level electric motor and electric motor elements that do not require consideration for demagnetization can be realized only by adopting a high coercive force magnet such as a NdFeB sintered magnet for the permanent magnet portion.

On the other hand, when a bonded magnet is employed for the permanent magnet portion mounted on the rotor, the coercive force of the bonded magnet is inferior to that of a magnet such as a NdFeB sintered magnet. For this reason, the detailed consideration regarding the demagnetization of a bond magnet, such as the material of the electromagnetic steel plate of a yoke part and the structure of a rotor, is required. In addition, compared with sintered magnets, such as a NdFeB sintered magnet, a bonded magnet has many freedom regarding the shape of bonded magnet itself, and arrangement | positioning to a rotor. Therefore, it is expected to recall a rotor with a new structure.

By the way, in the case of an electric motor element that employs a surface magnet type rotor, a protective tube provided to prevent magnet scattering during high-speed rotation cancels out the rotating magnetic field from the aforementioned stator by a magnetic field caused by eddy currents, It can be considered that the function of suppressing demagnetization of the film is fulfilled.

For example, a cylindrical protective tube made of non-magnetic material is installed on the outermost periphery of the rotor to prevent magnets from scattering during high-speed rotation. The reason why the protective tube is made of a nonmagnetic material is that it does not prevent the magnetic flux from the magnet provided in the rotor from interlinking with the stator. If the protective material is a magnetic material, the magnetic flux from the rotor magnet passes through the protective tube having a high magnetic permeability and branches to the adjacent magnetic pole. Therefore, the magnetic flux interlinking with the stator side is reduced, and the efficiency of the motor element is reduced.

For example, in addition to preventing the scattering of magnets, if it is intended to suppress the reduction in the efficiency of the motor due to eddy current loss, the center part of the rotor is not provided with a protection tube for preventing scattering, and only the upper and lower ends are prevented from scattering. It is also possible to recall a configuration for achieving this. That is, if there is a protective tube, the AC magnetic field generated from the stator is attenuated by the protective tube. Therefore, it is possible to avoid lowering the motor element efficiency by not providing the protective tube.

The prior art documents showing the above technical idea include, for example, Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4. There are many other documents with similar contents.

In recent years, the development of new bonded magnets that contribute to improving the performance of electric motor elements has been active. Utilization of this new bonded magnet is desired. In particular, the high performance of this new bonded magnet is desired to be applied to an interior permanent magnet (IPM) type rotor in which a bonded magnet (permanent magnet) is embedded in the rotor. However, as described above, when the operation state of the rotation drive of the electric motor element stops (so-called motor lock), the rotation of the rotor is stopped. It may occur when the rotating magnetic field from the stator is applied to the bonded magnet of the rotor as a reverse magnetic field that demagnetizes the magnetized state of the bonded magnet. Further, with the rotor configuration that follows the conventional technology, even if the coercive force of the bond magnet mounted on the rotor is slightly increased, the coercive force of the NdFeB sintered magnet or the like does not reach the high value. It is considered difficult to eliminate the demagnetization of the magnet.

JP 2010-259304 A JP 2009-95200 A JP 2000-31447 A Japanese Patent Laid-Open No. 10-304610

Therefore, an object of the present invention is to provide a motor element and a motor having a novel configuration in which resistance to demagnetization of the motor element is improved in a configuration in which a bond magnet is disposed inside the rotor.

In order to achieve the above-described object, the inventors of the present application conducted trial and error and conducted intensive studies. Details are described below.

The present invention is an electric motor element including a stator and a rotor having a plurality of magnetic poles. The rotor includes a configuration having magnetic saliency. In the configuration having magnetic saliency, a plurality of d-axis magnetic flux paths for generating magnet torque out of rotational torque components generated by a rotating magnetic field from the stator, and reluctance torque out of rotational torque components are provided. And a plurality of q-axis magnetic flux paths for generating. Each of the plurality of d-axis magnetic flux paths includes a bond magnet part, and each of the plurality of q-axis magnetic flux paths includes a bond magnet part or an adjacent part in contact with a bond magnet part different from the bond magnet part. An extension of a straight line connecting the centers of a plurality of magnetic poles and the center of the rotation axis of the rotor is defined as a d-axis, and the electrical angle is shifted by 90 degrees with respect to the d-axis and passes through the center of the rotation axis of the rotor. The magnetization direction in the main part of the bond magnet part, which is the main part of the bond magnet part located near the q axis, with the straight line as the q axis is the intersection of the magnetization direction virtual extension line of the magnetization direction and the q axis. Is one of the four corners at the intersection. This one corner is a corner portion sandwiched by the q-axis line segment between the intersection and the outer periphery of the rotor, and the magnetization direction virtual extension straight line, among the line segments included in the q-axis. The angle of the corner is in the range of 30 to 150 degrees.

According to the configuration of the present invention, the magnetic field generated from the stator side when the motor is locked becomes a reverse magnetic field and flows (out) in the radial direction of the rotor. By setting the magnetization direction of the portion to a predetermined angle, demagnetization of the bonded magnet portion can be suppressed. Therefore, it is possible to provide an electric motor element, an electric motor, an electric device, and the like including an embedded magnet rotor that can suppress deterioration of characteristics even when a magnetic field generated from the stator side acts when the motor is locked. Therefore, it has a great industrial value.

Sectional drawing which shows the structural example of the electric motor element of Embodiment 1. FIG. Sectional drawing which shows the cross section of the plane containing the rotating shaft of the electric motor element of Embodiment 1. FIG. FIG. 3 is an explanatory diagram showing a state in which a rotating magnetic field from a stator is applied as a reverse magnetic field to a rotor when the motor element according to the first embodiment is locked. FIG. 3 is a diagram illustrating a first aspect of a magnetization direction of a main part of the bonded magnet according to the first embodiment. FIG. 6 is a diagram illustrating a second aspect of the magnetization direction of the main part of the bonded magnet according to the first embodiment. 6 is a graph showing a simulation result of an induced voltage in the first embodiment. FIG. 5 is a perspective view showing a structural example of a motor element according to a second embodiment. The top view which looked at the electric motor element of Embodiment 2 from the rotating shaft direction. The figure which shows the magnetization direction of the bond magnet part principal part in Embodiment 2. FIG. Explanatory drawing which shows the state by which the rotating magnetic field from a stator was applied to a rotor as a reverse magnetic field at the time of the motor lock of the electric motor element of Embodiment 2. FIG. Schematic which shows the magnetization direction of the embedded magnet type | mold rotor shown as an example of a prior art example.

Hereinafter, the present invention will be described with reference to the drawings. In addition, this invention is not limited by each following embodiment.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing a structural example of the electric motor element according to the present embodiment. FIG. 2 is a cross-sectional view showing a cross section of a plane including the rotation shaft of the electric motor element of the present embodiment. The combination of the number of poles and the number of slots of the motor element shown in FIG. 1 is a so-called concentrated winding configuration of 6 poles and 9 slots. The electric motor element includes a stator 1 having a concentrated winding body in nine teeth and a rotor 2 having six magnetic poles having magnetic saliency.

The configuration of the motor element in the present invention is not limited to this. In FIG. 1, a wound body 6 by concentrated winding in which a winding is wound around one tooth portion 5 is illustrated, but the present invention is not limited to this. For example, various winding modes such as distributed winding or wave winding in which the winding is wound across the plurality of teeth portions 5 can be employed.

The wound body 6 includes, for example, a 10 pole 9 slot concentrated winding configuration, a 10 pole 12 slot concentrated winding configuration, a 12 pole 9 slot concentrated winding configuration, a 14 pole 12 slot concentrated winding configuration, 4 poles. 24-slot distributed winding configuration, 4-pole 36-slot distributed winding configuration, 6-pole 36-slot distributed winding configuration, 8-pole 48-slot distributed winding configuration, 4-pole 12-slot wave winding configuration, 4-pole The present invention can be applied to any known combination of the number of poles and the number of slots, such as a 12-slot wave winding configuration and a 6-pole 18-slot wave winding configuration.

As shown in FIG. 1, the electric motor element 14 in the present embodiment includes a substantially cylindrical stator 1 and a rotor 2 that is rotatably held inside the stator 1. A shaft hole 3 is provided at the center of the rotor 2. The rotor 2 and the shaft are fixed with a shaft (not shown) inserted through the shaft hole 3. Note that both ends of the shaft include a pair of bearings that rotatably support the shaft. In FIG. 1, the shaft and the bearing are self-explanatory and are not shown.

The stator 1 includes a substantially cylindrical yoke portion 4, a core 7 of the stator 1 having a tooth portion 5 extending inside the yoke portion 4, and an insulated wire wound around each of the tooth portions 5. And a wound body 6 provided. Between the teeth part 5 and the wound body 6, an insulator 8 that electrically insulates the two is provided. The rotor 2 includes a bonded magnet portion 10 in each of a core 9 of the columnar rotor 2 and a plurality of arrangement holes 11 formed in the circumferential direction of the rotor 2 (six in this example). In addition, as a material of the core wire of the insulated wire constituting the wound body 6, a material containing inevitable impurities and any of copper, copper alloy, aluminum, or aluminum alloy is used. The core 7 of the stator 1 is constituted by a laminated body of electromagnetic steel plates. An electromagnetic steel sheet is punched to form a stator core sheet including a yoke part and a tooth part, and a plurality of stator core sheets are laminated to form a laminated body of electromagnetic steel sheets as the core 7 of the stator 1. Constitute. The electromagnetic steel sheet contains Fe and Si as main components, and is not particularly limited as subcomponents. The components of the electrical steel sheet include inevitable impurities that cannot be specified. The surface of the electrical steel sheet has an insulating coating. For example, an electromagnetic steel plate manufactured by Nippon Steel & Sumikin Co., Ltd., called 35H300, may be used for the core 7 of the stator 1 as an equivalent to the electromagnetic steel plate. The thickness dimension of 35H300 is 0.35 mm.

FIG. 4A is a diagram showing an aspect 1 of the magnetization direction of the main part of the bonded magnet in the first embodiment. FIG. 4B is a diagram showing an aspect 2 of the magnetization direction of the main part of the bonded magnet in the first embodiment. In the present embodiment, an electromagnetic steel plate called 35H300 used for the core 7 of the stator 1 may be employed for the core 9 of the rotor 2. As will be described later, even when an electromagnetic steel plate called 35H300 is adopted for the core 9 of the rotor 2, the magnetization direction 10a of the bond magnet portion main part 10c of the bond magnet portion 10 is defined as the outer periphery of the rotor 2. The demagnetization of the bonded magnet unit 10 can be suppressed by setting the angle θ between the corners sandwiched between the q-axis line between the two and the virtual extension straight line of the magnetization direction 10a to a range of 30 degrees to 150 degrees. is there. The magnetic field generated from the stator 1 side when the motor is locked acts as a reverse magnetic field, and this reverse magnetic field flows from the substantial radial direction of the rotor 2 to cause demagnetization in the bond magnet unit 10. It can be suppressed. The direction of the magnetic field generated from the side of the stator 1 when the motor is locked and the magnetization direction 10a of the main part 10c of the bonded magnet are not opposite to each other and are different from each other. It is considered that the demagnetization of the part 10 is suppressed.

The bonded magnet unit 10 includes at least magnet powder and a resin material. The type of magnetic material of the magnet powder is not particularly limited. For example, Nd—Fe—B magnet powder, Sm—Co magnet powder, Sm—Fe—N magnet powder, ferrite magnet powder, or a mixture thereof Etc. are selected as appropriate. Although the cross-sectional shape of the surface perpendicular to the axial direction of the bonded magnet portion 10 shows a substantially V-shaped shape, it is not limited to this shape. A mode suitable for the specifications of the motor element, such as a rectangle, a trapezoid, a U-shape, and an arc shape, is appropriately selected.

Although it is the physique of the rotor 2 in this Embodiment, the diameter of the rotor 2 is the range of 30 mm to 60 mm. The length dimension in the longitudinal direction of the rotation axis of the rotor 2 (columnar length dimension) is in the range of 15 mm to 60 mm. In the case of such a physique of the rotor 2, the thickness dimension of the bonded magnet portion 10 in a cross section perpendicular to the rotation axis of the rotor 2 needs to be at least about 2 mm. The physique of the stator 1 is selected according to the physique of the rotor 2.

The angle θ between the magnetization direction 10a of the bonded magnet main part 10c and the q-axis line between the outer periphery of the rotor 2 and the virtual extension straight line of the magnetization direction 10a is set to 30 to 150 degrees. The range occupied by the main part 10c of the bonded magnet part in the bonded magnet part 10 is as follows. When the diameter of the rotor 2 is about 60 mm, it is preferable that the diameter is from the vicinity of the outer diameter of the rotor 2 to the diameter of about 20 mm inside the rotor 2. When the diameter of the rotor 2 is about 30 mm, it is preferable that the diameter is from the vicinity of the outer diameter of the rotor 2 to the diameter of about 10 mm inside the rotor 2.

As described above, the motor element 14 in the present embodiment includes at least the stator 1 and the rotor 2 having a plurality of magnetic poles. The rotor 2 includes a configuration having magnetic saliency. The configuration having the magnetic saliency includes a plurality of d-axis magnetic flux paths for generating a magnet torque, and a rotational torque component among the rotational torque components generated by the rotating magnetic field from the stator 1. A plurality of q-axis magnetic flux paths for generating reluctance torque. Bond magnet part 10 is included in at least a part of each of the plurality of d-axis magnetic flux paths, and bond magnet part 10 or a bond magnet part different from bond magnet part 10 is in contact with at least a part of each of the plurality of q-axis magnetic flux paths. Including adjacent parts. An extension of a straight line connecting each of the centers of the plurality of magnetic poles and the center of the rotation axis of the rotor 2 is defined as a d-axis 2d, and the rotor is deviated by 90 degrees in electrical angle with respect to each of the d-axis 2d. The magnetization direction 10a in the main part 10c of the bond magnet part 10c of the bond magnet part 10 arranged at a position close to each of the q axes 2q is defined as a magnetization direction 10a with a straight line passing through the center of the rotation axis 2 as q axis 2q. This is one of the four corners at the intersection formed by the intersection of the magnetization direction virtual extension straight line 10b in the direction 10a and the q axis 2q. One corner is a corner portion sandwiched between the q-axis line segment 2r between the intersection and the outer periphery of the rotor 2 and the magnetization direction virtual extension straight line 10b among the line segments included in the q-axis 2q. The angle θ of the corner is in the range of 30 degrees to 150 degrees.

In the electric motor element of the present embodiment, the magnetic field generated from the stator 1 side when the motor is locked becomes a reverse magnetic field and flows from the substantial radial direction of the rotor 2 to demagnetize the bonded magnet unit 10. It was confirmed that this phenomenon (demagnetization) can be suppressed. The confirmation method and the result are described below. The confirmation method used numerical analysis of the magnetic field by the finite element method. In this numerical analysis, first, an induced voltage is calculated for an electric motor element including a rotor 2 having a bonded magnet portion that is not demagnetized. Next, the rotor 2 is rotated only once in a state in which a DC demagnetizing current is applied from one phase to the other two phases among the three-phase coils configured as the winding body of the stator 1. Thereafter, the induced voltage is calculated again. A change (decrease rate) in the induced voltage before and after the application of the demagnetizing current is obtained and defined as a demagnetizing factor. A graph of the results is shown in FIG. FIG. 5 is a graph showing a simulation result of the induced voltage in the first embodiment.

Note that the value of the reverse magnetic field in the above numerical analysis is such that demagnetization occurs in the bond magnet unit 10 when the direction of the reverse magnetic field and the direction of the magnetic field of the bond magnet unit 10 face each other in the opposite direction. Is the value of the magnetic field. The numerical analysis was performed assuming that the value of the reverse magnetic field in the above numerical analysis was a value that was about 20% higher than the value of the holding force Hcj of the bonded magnet. As the magnetic characteristics of the bonded magnet used in this embodiment, the holding force Hcj is about 850 [kA / m]. The residual magnetic flux density Br is about 630 [mT]. The density is about 5.0 [Mg / m ³ ].

The magnetization direction 10a of the bond magnet portion main portion 10c of the bond magnet portion 10 is equal to the angle θ of the corner portion sandwiched between the q-axis line between the outer periphery of the rotor 2 and the virtual extension straight line of the magnetization direction 10a. . The angle θ was changed from 10 degrees to 170 degrees, and the reduction rate of the induced voltage was obtained by numerical analysis. The results shown in FIG. 5 show that when the angle θ, which is the magnetization direction 10a shown in FIG. 4A, is in the range of 30 degrees to 150 degrees, the demagnetization factor is less than 1%, and the influence of demagnetization is small.

As shown in FIG. 4A (mode 1), the angle θ of the magnetization direction 10a of the main part of the bond magnet unit 10 is set to a substantially constant angle in all the main parts of the bond magnet unit 10. preferable. Further, as shown in FIG. 4B (mode 2), the angle θ1, the angle θ2 to the angle θn (n is a natural number of 3 or more) of the magnetization direction 10a for each portion of the bond magnet portion main portion 10c of the bond magnet portion 10. It is slightly different and may be dispersed within a certain angle width.

The relationship between the angle θ, which is the magnetization direction 10a, and the demagnetization factor is as shown in FIG. If the angle θ, which is the magnetization direction 10a, is 30 degrees, the demagnetization factor is about 1%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 40 degrees, the demagnetization factor is about 0.75%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 50 degrees, the demagnetization factor is about 0.6%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 60 degrees, the demagnetization factor is about 0.5%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 70 degrees, the demagnetization factor is about 0.4%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 80 degrees, the demagnetization factor is about 0.25%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 90 degrees, the demagnetization factor is about 0.25%, and the influence of demagnetization is slight, which is preferable.

If the angle θ, which is the magnetization direction 10a, is 100 degrees, the demagnetization factor is about 0.25%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 110 degrees, the demagnetization factor is about 0.3%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 120 degrees, the demagnetization factor is about 0.45%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 130 degrees, the demagnetization factor is about 0.65%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 140 degrees, the demagnetization factor is about 0.75%, and the influence of demagnetization is slight, which is preferable.

If the angle θ, which is the magnetization direction 10a, is 150 degrees, the demagnetization factor is about 1%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 30 ° to 150 °, the demagnetization rate is less than about 1%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 30 to 90 degrees, the demagnetization factor is a value in the range of about 1% to about 0.25%, and the influence of demagnetization is small, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 40 degrees to 90 degrees, the demagnetization factor is a value in the range of about 0.75% to about 0.25%, and the influence of demagnetization is small, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 50 degrees to 90 degrees, the demagnetization factor is a value in the range of about 0.6% to about 0.25%, and the influence of demagnetization is small, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 60 degrees to 90 degrees, the demagnetization factor is a value in the range of about 0.5% to about 0.25%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 70 to 90 degrees, the demagnetization factor is a value in the range of about 0.4% to about 0.25%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is set to 30 ° to 110 °, the demagnetization factor is a value in the range of about 1% to about 0.25%, and the influence of demagnetization is slight, which is preferable.

When the angle θ, which is the magnetization direction 10a, is 30 degrees to 130 degrees, the demagnetization factor is about 1% or a value in the range of about 0.65% to about 0.25%, and the influence of demagnetization is slight, which is preferable. .

As described above, as a result of the numerical analysis, the value of the reverse magnetic field indicates that when the direction of the reverse magnetic field and the direction of the magnetization direction magnetic field of the bond magnet unit 10 face each other in the opposite direction, the bonded magnet unit 10 As the value of the magnetic field at which demagnetization occurs in the magnetic field, the value was increased by about 20% from the value of the holding force Hcj of the bonded magnet, and numerical analysis was performed. In addition, the magnetic characteristics of the bond magnet used in this embodiment are isotropic magnetic characteristics. The holding force Hcj is about 850 [kA / m]. The residual magnetic flux density Br is about 630 [mT]. Numerical analysis was performed assuming that the density was about 5.0 [Mg / m ³ ].

If the value of the reverse magnetic field is a very large value, for example, about 10 to 100 times the value of the holding force Hcj of the bond magnet, the bond magnet will go through demagnetization and become demagnetized. It reaches a state in which it is magnetized (magnetized) in a close state or a magnetization direction that is the same as the direction of the reverse magnetic field. This is obvious even if it is not explained.

Further, the number of poles of the rotor 2 in the present embodiment is 6, but the present embodiment is applicable if it is 2n times (n is a natural number).

In addition, FIG. 5 is a result at the time of using the electromagnetic steel plate by Nippon Steel & Sumikin Co., Ltd. called 35H300 for the rotor 2. FIG. Even when other types of electromagnetic steel sheets or steel materials are used for the rotor 2, the same tendency is shown and there is no great difference. Therefore, it cannot be overemphasized that the result of this Embodiment can be used.

In the motor element in the present embodiment, the rotor 2 has magnetic saliency. As shown in FIG. 1, the portion of the rotor 2 that is crossed by the arrow 12 is a d-axis magnetic flux path constituting portion, and generates a magnet torque among the components of the rotational torque generated by the rotating magnetic field from the stator 1. The part of the rotor 2 crossed by the arrow 13 is a q-axis magnetic flux path constituting part, and generates a reluctance torque among the components of the rotational torque generated by the rotating magnetic field from the stator 1. The d-axis magnetic flux path component and the q-axis magnetic flux path component include at least one of the laminate of the bond magnet part and the steel plate.

The steel plate included in the rotor 2 of the motor element in the present embodiment may include at least Fe and Si having an upper limit value of 0.8 wt% in the steel plate components. According to the configuration in the present embodiment, since the Si content of the steel sheet is made small, the electrical conductivity of the steel sheet is smaller than the electrical conductivity of the electromagnetic steel sheet. The eddy current of the steel sheet generated by electromagnetic induction due to the reverse magnetic field from the outside shows a larger value than the eddy current in the electromagnetic steel sheet. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

The steel plate included in the rotor 2 of the motor element in the present embodiment is a steel plate that does not have an insulating coating. That is, by forming the core of the rotor 2 as a laminated body of steel plates, the ground surfaces of the steel plates are in contact with each other. Moreover, you may apply | coat to the steel plate the electroconductive material which raises the electrical continuity between the base materials of a steel plate. With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

The steel plate included in the rotor 2 of the electric motor element in the present embodiment is a steel plate having 0.35 mm as the lower limit of the thickness dimension. The magnetic field generated from the side of the stator 1 when the motor is locked increases the thickness of the steel plate, thereby generating more eddy currents near the outer periphery of the rotor 2 and suppressing demagnetization of the bond magnet portion. It is. In the case of an electromagnetic steel sheet, the thickness dimension may be about 0.5 mm. The steel plate included in the electric motor element in the present embodiment may include at least Fe and Si having an upper limit of 0.8 wt% in the steel plate components. The thickness dimension of the steel plate may be about 0.5 mm. For example, a steel sheet made by Nippon Steel & Sumikin Co., Ltd. called 50H470, 50H400 or 50H350 may be used with the thickness dimension of the steel sheet being about 0.5 mm. With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

It should be noted that an oxide film due to natural oxidation is unavoidably formed on the base of the steel plate. Therefore, the electric motor element in the present embodiment includes a configuration in which the ground surfaces of the steel plates are in contact with each other and a configuration in which the steel plates are in contact with each other through an oxide film formed by natural oxidation of the ground surface. In addition, at least a part of the surface of the rotor 2 may be provided with a coating covering the surface of the rotor 2 in order to suppress an oxide film due to natural oxidation that inevitably occurs on the base of the steel plate. . With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

When the motor element of the present embodiment is rotationally driven, if the motor element is locked due to some factor, the rotating magnetic field from the stator 1 is applied to the rotor 2 while the rotation of the rotor 2 is stopped. May act as a reverse magnetic field. The situation is schematically shown in FIG. FIG. 3 is an explanatory diagram illustrating a state in which the rotating magnetic field from the stator 1 is applied as a reverse magnetic field to the rotor 2 when the motor element of the first embodiment is locked. An arrow 15 shown in FIG. 3 schematically shows the above-described reverse magnetic field. As described above, this reverse magnetic field is a rotating magnetic field. For this reason, when this reverse magnetic field is applied in a direction that causes demagnetization of the magnet mounted on the rotor 2, the magnet may be demagnetized. For this reason, it has been continuously recognized as a problem.

The manufacturing method of the core of the motor element (the core of the stator 1 and the core of the rotor 2) using the steel plate or the electromagnetic steel plate in the present embodiment is as follows. A rolled steel plate or electromagnetic steel plate supplied from a manufacturer of metal materials or the like is sent to a press machine by an unwinding machine. A steel plate or an electromagnetic steel plate is punched into a core sheet having a predetermined axial cross-sectional shape by a mold installed in a press. By laminating and integrating the core sheets, a core (a laminated body configured by laminating core sheets which are processed products from steel plates or electromagnetic steel plates) is formed.

As described above, the electric motor element 14 of the present embodiment includes the stator 1 and the rotor 2 having a plurality of magnetic poles. The rotor 2 includes a configuration having magnetic saliency. The configuration having magnetic saliency includes a plurality of d-axis magnetic flux passages for generating a magnet torque among the rotational torque components generated by the rotating magnetic field from the stator 1, and the reluctance torque among the rotational torque components. And a plurality of q-axis magnetic flux paths for generating. Each of the plurality of d-axis magnetic flux paths includes a bond magnet unit 10, and each of the plurality of q-axis magnetic flux paths includes a bond magnet unit 10, or an adjacent part in contact with a bond magnet unit different from the bond magnet unit 10 including. An extension of a straight line connecting the centers of the plurality of magnetic poles and the center of the rotation axis of the rotor 2 is defined as a d-axis 2d, and is deviated by 90 degrees in electrical angle with respect to the d-axis 2d. With the straight line passing through the center as the q-axis 2q, the magnetization direction in the bond magnet part main part 10c, which is the main part of the bond magnet part 10 located in the vicinity of the q axis 2q, is a virtual extension of the magnetization direction of the magnetization direction. It is one of the four corners at the intersection formed by the intersection of the straight line and the q axis 2q. One corner is a corner portion sandwiched between the q-axis line segment 2r between the intersection and the outer periphery of the rotor 2 and the magnetization direction virtual extension straight line 10b among the line segments included in the q-axis 2q. The angle of the corner is in the range of 30 to 150 degrees.

As a result, the magnetic field generated from the stator 1 side when the motor is locked becomes a reverse magnetic field and flows in (out) in the substantial radial direction of the rotor 2, whereas the magnetization of the main part 10c of the bonded magnet portion. By setting the direction 10a to a predetermined angle, demagnetization of the bonded magnet unit 10 can be suppressed. Therefore, it is possible to provide an electric motor element, an electric motor, an electric device, and the like including an embedded magnet type rotor that can suppress deterioration of characteristics even when a magnetic field generated from the stator 1 side acts when the motor is locked. . Therefore, it has a great industrial value.

It is more preferable that the angle is in the range of 30 degrees to 90 degrees.

More preferably, the angle is in the range of 40 degrees to 90 degrees.

More preferably, the angle is in the range of 50 to 90 degrees.

More preferably, the angle is in the range of 60 to 90 degrees.

More preferably, the angle is in the range of 70 degrees to 90 degrees.

It is more preferable that the angle is in the range of 30 degrees to 110 degrees.

It is more preferable that the angle is in the range of 30 degrees to 130 degrees.

The cross-sectional shape of the bond magnet portion in the cross section perpendicular to the rotation axis of the rotor 2 may be a V-shape.

The cross-sectional shape of the bond magnet portion in the cross section perpendicular to the rotation axis of the rotor 2 may be a U-shape.

The cross-sectional shape of the bond magnet portion in the cross section perpendicular to the axis of rotation of the rotor 2 may be an arc shape.

It is preferable that the lower limit value of the thickness dimension of the bonded magnet portion 10 in the cross section in the vertical direction with respect to the rotation axis of the rotor 2 is 2 mm.

The diameter of the rotor is preferably in the range of 30 mm to 60 mm.

A part of each of the plurality of d-axis magnetic flux paths and a part of each of the plurality of q-axis magnetic flux paths include a laminate in which a plurality of steel sheets are laminated, and the steel sheet components are Fe and 0.8 wt%. Si as the upper limit value may be included.

The laminated body included in the rotor 2 may include a configuration in which the ground surfaces of the steel plates are in contact with each other.

The laminated body included in the rotor 2 may include a configuration in which the ground surfaces of the steel plates are in contact with each other and a configuration in which the steel plates are in contact with each other through an oxide film formed by natural oxidation of the ground surfaces.

The laminated body included in the rotor 2 may include a steel plate having a lower limit value of the thickness dimension of 0.35 mm.

The rotor 2 may include a coating that covers the surface of the rotor 2.

The stator 1 of the electric motor element 14 includes a core 7 of the stator 1 having a substantially cylindrical yoke portion 4 and a plurality of teeth portions 5 extending inside the yoke portion 4, and a plurality of teeth. The core 7 of the stator 1 may include a laminated body of electromagnetic steel sheets.

Also, the electric motor of the present embodiment includes an electric motor element, an output shaft that outputs the rotational torque of the electric motor element, and a bearing that rotatably supports the output shaft. Thereby, a highly reliable electric motor is provided.

Also, the apparatus according to the present embodiment is equipped with an electric motor including an electric motor element, an output shaft that outputs rotational torque of the electric motor element, and a bearing that rotatably supports the output shaft. This provides a highly reliable device.

(Embodiment 2)
FIG. 6 is a perspective view showing a structural example of the electric motor element of the present embodiment. FIG. 7 is a plan view of the electric motor element of the present embodiment as viewed from the direction of the rotation axis. The combination of the number of poles and the number of slots of the motor element of the present embodiment shown in FIGS. 6 and 7 is a so-called concentrated winding configuration of 10 poles and 12 slots. The electric motor element includes a stator 1 having concentrated winding bodies at 12 tooth portions, and a rotor 2 having 10 magnetic pole portions having magnetic saliency. Other configurations are the same as those in the first embodiment.

When the motor element of the present embodiment is rotationally driven, if the motor element is locked due to some factor, the rotating magnetic field from the stator 1 is reversed to the rotor 2 while the rotation of the rotor 2 is stopped. May act as a magnetic field. The situation is schematically shown in FIG. As described above, since this reverse magnetic field is a rotating magnetic field, it has been conventionally recognized as a problem that when this reverse magnetic field is applied in a direction that causes demagnetization of the magnet mounted on the rotor 2, the magnet is demagnetized. It had been.

6 and 7 exemplify the wound body 6 by concentrated winding in which the winding is wound around one tooth portion 5, but the present invention is not limited to this. The winding body 6 can employ various winding modes such as distributed winding or wave winding in which the winding is wound across the plurality of tooth portions 5.

The wound body 6 includes, for example, a 10 pole 9 slot concentrated winding configuration, a 10 pole 12 slot concentrated winding configuration, a 12 pole 9 slot concentrated winding configuration, a 14 pole 12 slot concentrated winding configuration, 4 poles. 24-slot distributed winding configuration, 4-pole 36-slot distributed winding configuration, 6-pole 36-slot distributed winding configuration, 8-pole 48-slot distributed winding configuration, 4-pole 12-slot wave winding configuration, 4-pole The present invention can be applied to any known combination of the number of poles and the number of slots, such as a 12-slot wave winding configuration and a 6-pole 18-slot wave winding configuration. Further, the number of poles of the rotor 2 in the present embodiment is 10, but the present invention is applicable if it is 2n times (n is a natural number).

As shown in FIGS. 6 and 7, the electric motor element 14 in the present embodiment includes a substantially cylindrical stator 1 and a rotor 2 that is rotatably held inside the stator 1. A shaft hole 3 is provided at the center of the rotor 2. The rotor 2 and the shaft are fixed in a state where a shaft (not shown) is inserted into the shaft hole 3. Note that both ends of the shaft include a pair of bearings that rotatably support the shaft. 6 and 7, the shaft and the bearing are obvious and are not shown.

The stator 1 includes a substantially cylindrical yoke portion 4, a core 7 of the stator 1 having a tooth portion 5 extending inside the yoke portion 4, and an insulated wire wound around each of the tooth portions 5. And a wound body 6 provided. Between the teeth part 5 and the wound body 6, an insulator (not shown) that electrically insulates both is provided. The rotor 2 includes a bonded magnet portion 20 in each of a core 9 of the columnar rotor 2 and a plurality of arrangement holes 11 formed in the circumferential direction of the rotor 2 (10 locations in this example). In addition, as a material of the core wire of the insulated wire constituting the wound body 6, a material containing inevitable impurities and any of copper, copper alloy, aluminum, or aluminum alloy is used. The core 7 of the stator 1 is constituted by a laminated body of electromagnetic steel plates. An electromagnetic steel sheet is punched to form a stator core sheet including a yoke part and a tooth part, and a plurality of stator core sheets are laminated to form a laminated body of electromagnetic steel sheets as the core 7 of the stator 1 To do. The electromagnetic steel sheet contains Fe and Si as main components, and is not particularly limited as subcomponents. The components of the electrical steel sheet include inevitable impurities that cannot be specified. The surface of the electrical steel sheet has an insulating coating. As a thing equivalent to the above, you may use the electromagnetic steel plate by Nippon Steel & Sumikin Co., Ltd. called 35H300 for the core 7 of the stator 1, for example. The thickness dimension of 35H300 is 0.35 mm.

FIG. 8 is a diagram showing the magnetization direction of the main part of the bonded magnet in the second embodiment. In the present embodiment, an electromagnetic steel plate called 35H300 used for the core 7 of the stator 1 may be employed for the core 9 of the rotor 2. As described above, even when an electromagnetic steel plate called 35H300 is adopted for the core 9 of the rotor 2, the magnetization direction 20a of the main part 20c of the bonded magnet part in the bonded magnet part 20 is set to the outer periphery of the rotor 2. The demagnetization of the bonded magnet unit 20 can be suppressed by setting the angle θ between the corners sandwiched by the q-axis line between them and the virtual extended straight line 20b of the magnetization direction 20a to be in the range of 30 degrees to 150 degrees. is there. The magnetic field generated from the stator 1 side when the motor is locked acts as a reverse magnetic field, and this reverse magnetic field flows from the substantial radial direction of the rotor 2 to cause demagnetization in the bond magnet unit 20. It can be suppressed. The direction of the magnetic field generated from the side of the stator 1 when the motor is locked and the magnetization direction 20a of the main part of the bond magnet unit 20 are not opposite to each other and are different from each other. It is considered that the demagnetization of the magnet unit 20 is suppressed.

The bonded magnet unit 20 includes at least magnet powder and a resin material. The type of magnetic material of the magnet powder is not particularly limited. For example, Nd—Fe—B magnet powder, Sm—Co magnet powder, Sm—Fe—N magnet powder, ferrite magnet powder, or a mixture thereof Etc. are selected as appropriate. The cross-sectional shape of the surface perpendicular to the axial direction of the bond magnet unit 20 shows a case of a substantially arc shape, but is not limited to this shape. A mode suitable for the specifications of the motor element, such as a rectangle, a trapezoid, and a V shape, is appropriately selected.

Although it is the physique of the rotor 2 in this Embodiment, the diameter of the rotor 2 is the range of 30 mm to 60 mm. The length dimension in the longitudinal direction of the rotation axis of the rotor 2 (columnar length dimension) is in the range of 15 mm to 60 mm. In the case of such a physique of the rotor 2, the thickness dimension of the bonded magnet portion 20 in a cross section perpendicular to the rotation axis of the rotor 2 needs to be at least about 2 mm. The physique of the stator 1 is selected according to the physique of the rotor 2.

The angle θ of the corner sandwiched between the magnetization direction 20a of the bonded magnet portion 20c in the bonded magnet portion 20 and the q-axis line between the outer periphery of the rotor 2 and the virtual extension straight line 20b of the magnetization direction 20a is defined as The range occupied by the main part 20c of the bonded magnet part 20 in the bonded magnet part 20 when 30 degrees to 150 degrees is as follows. When the diameter of the rotor 2 is about 60 mm, it is preferable that the diameter is from the vicinity of the outer diameter of the rotor 2 to the diameter of about 20 mm inside the rotor 2. When the diameter of the rotor 2 is about 30 mm, it is preferable that the diameter is from the vicinity of the outer diameter of the rotor 2 to the diameter of about 10 mm inside the rotor 2.

Further, in the electric motor element according to the present embodiment, the rotor 2 has magnetic saliency, and a d-axis magnetic flux path configuration section that generates magnet torque and a q-axis magnetic flux path configuration that generates reluctance torque. Part. These d-axis magnetic flux path constituent parts and q-axis magnetic flux path constituent parts include at least a laminate of either a bond magnet part or a steel plate.

The steel plate included in the rotor 2 of the motor element in the present embodiment may include at least Fe and Si having an upper limit value of 0.8 wt% in the steel plate components. According to the configuration in the present embodiment, since the Si content of the steel sheet is made small, the electrical conductivity of the steel sheet is smaller than the electrical conductivity of the electromagnetic steel sheet. The eddy current of the steel sheet generated by electromagnetic induction due to the reverse magnetic field from the outside shows a larger value than the eddy current in the electromagnetic steel sheet. The reverse magnetic field from the outside is canceled out by the eddy current in the vicinity of the outer periphery of the rotor 2, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

The steel plate included in the rotor 2 of the motor element in the present embodiment is a steel plate that does not have an insulating coating. That is, by forming the core of the rotor 2 as a laminated body of steel plates, the ground surfaces of the steel plates are in contact with each other. Moreover, you may apply | coat to the steel plate the electroconductive material which raises the electrical continuity between the base materials of a steel plate. With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

The steel plate included in the rotor 2 of the electric motor element in the present embodiment is a steel plate having 0.35 mm as the lower limit of the thickness dimension. The magnetic field generated from the side of the stator 1 when the motor is locked increases the thickness of the steel plate, thereby generating more eddy currents near the outer periphery of the rotor 2 and suppressing demagnetization of the bond magnet portion. It is. In the case of an electromagnetic steel sheet, the thickness dimension may be about 0.5 mm. The steel plate included in the electric motor element in the present embodiment may include at least Fe and Si having an upper limit of 0.8 wt% in the steel plate components. The thickness dimension of the steel plate may be about 0.5 mm. For example, a steel sheet made by Nippon Steel & Sumikin Co., Ltd. called 50H470, 50H400 or 50H350 may be used with the thickness dimension of the steel sheet being about 0.5 mm. With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

It should be noted that an oxide film due to natural oxidation is unavoidably formed on the base of the steel plate. Therefore, the electric motor element in the present embodiment includes a configuration in which the ground surfaces of the steel plates are in contact with each other and a configuration in which the steel plates are in contact with each other through an oxide film formed by natural oxidation of the ground surface. In addition, a coating covering the surface of the rotor 2 may be provided on at least a part of the surface of the rotor 2 in order to suppress an oxide film due to natural oxidation inevitably occurring on the ground surface of the steel plate. . With this configuration, eddy currents are likely to occur near the outer periphery of the rotor 2. The reverse magnetic field from the outside is canceled out by this eddy current, and the effect of suppressing the occurrence of demagnetization of the bonded magnet portion is enhanced.

When the motor element of the present embodiment is rotationally driven, if the motor element is locked due to some factor, the rotating magnetic field from the stator 1 is reversed to the rotor 2 while the rotation of the rotor 2 is stopped. May act as a magnetic field. The situation is schematically shown in FIG. FIG. 9 is an explanatory diagram showing a state in which the rotating magnetic field from the stator is applied as a reverse magnetic field to the rotor when the motor element of the present embodiment is locked. An arrow 15 shown in FIG. 9 schematically shows the above-described reverse magnetic field. As described above, this reverse magnetic field is a rotating magnetic field. For this reason, when this reverse magnetic field is applied in a direction that causes demagnetization of the magnet mounted on the rotor 2, the magnet may be demagnetized. For this reason, it was conventionally recognized as a problem.

In addition, the manufacturing method of the core of the motor element (the core of the stator 1 and the core of the rotor 2) using the steel plate or the electromagnetic steel plate in the present embodiment is as follows. A rolled steel plate or electromagnetic steel plate supplied from a manufacturer of metal materials or the like is sent to a press machine by an unwinding machine. A steel plate or an electromagnetic steel plate is punched into a core sheet having a predetermined axial cross-sectional shape by a mold installed in a press. By laminating and integrating the core sheets, a core (a laminated body formed by laminating a core sheet that is a processed product from a steel plate or an electromagnetic steel plate is referred to as a core) is formed.

As described above, when the magnetic field from the stator 1 side reaches the rotor 2 when the motor is locked, more eddy current is generated in the vicinity of the outer periphery of the rotor 2 with respect to the magnetic field from the stator 1. The magnetic field due to this eddy current acts in a direction to cancel the magnetic field from the outside. As a result, the magnetic field from the stator 1, which is a magnetic field from the outside, is canceled near the outer periphery of the rotor 2, and the area inside the rotor 2 that is affected by the magnetic field from the stator 1 becomes small. It is also possible to reduce the amount of magnetic flux acting on the magnet part. Therefore, demagnetization of the bonded magnet portion can be suppressed.

The present invention suppresses demagnetization due to application of a reverse magnetic field to the bond magnet part included in the motor element and the rotor of the motor. Therefore, the present invention can provide an electric motor and an electric motor element with improved reliability.

DESCRIPTION OF SYMBOLS 1 Stator 2 Rotor 2d d-axis 2q q-axis 2r q-axis line segment 3 Shaft hole 4 Yoke part 5 Teeth part 6 Winding body 7 Core 8 Insulator 9 Core 10 Bond magnet part 10a Magnetization direction 10b Magnetization direction virtual extension straight line 10c Bond Magnet part 11 Arrangement hole 12 Arrow 13 Arrow 14 Motor element 15 Arrow 16 Arrow 20 Bonded magnet part 20a Magnetizing direction 20b Virtual extension straight line 20c Bonded magnet part essential part θ angle θ1 angle θ2 angle θn angle

Claims (21)

1. An electric motor element including a stator and a rotor having a plurality of magnetic poles,
   The rotor includes a configuration having magnetic saliency,
   The configuration having the magnetic saliency includes a plurality of d-axis magnetic flux passages for generating a magnet torque out of the rotational torque components generated by the rotating magnetic field from the stator, and the rotational torque components. A plurality of q-axis magnetic flux paths for generating reluctance torque,
   A part of each of the plurality of d-axis magnetic flux paths includes a bond magnet part, and a part of each of the plurality of q-axis magnetic flux paths is adjacent to the bond magnet part or a bond magnet part different from the bond magnet part. Part
   An extension of a straight line connecting the centers of the plurality of magnetic poles and the center of the rotation axis of the rotor is defined as a d-axis, and an electrical angle of 90 degrees with respect to the d-axis, and the rotation axis of the rotor A straight line passing through the center of
   The magnetization direction in the main part of the bond magnet part, which is the main part of the bond magnet part located near the q axis, is formed by the intersection of the magnetization direction virtual extension straight line of the magnetization direction and the q axis. One of the four corners at the intersection,
   The one corner is a corner portion sandwiched between the q-axis line segment between the intersection and the outer periphery of the rotor, and the magnetization direction virtual extension straight line, of the line segments included in the q-axis. ,
   The motor element having an angle of the corner in a range of 30 degrees to 150 degrees.
2. The motor element according to claim 1, wherein the angle is in a range of 30 degrees to 90 degrees.
3. The motor element according to claim 1, wherein the angle is in a range of 40 degrees to 90 degrees.
4. The motor element according to claim 1, wherein the angle is in a range of 50 degrees to 90 degrees.
5. The electric motor element according to claim 1, wherein the angle is in a range of 60 degrees to 90 degrees.
6. The motor element according to claim 1, wherein the angle is in a range of 70 degrees to 90 degrees.
7. The motor element according to claim 1, wherein the angle is in a range of 30 degrees to 110 degrees.
8. The electric motor element according to claim 1, wherein the angle is in a range of 30 degrees to 130 degrees.
9. The electric motor element according to claim 1, wherein a cross-sectional shape of the bond magnet portion in a cross section perpendicular to the rotation axis of the rotor is a V-shape.
10. 2. The electric motor element according to claim 1, wherein a cross-sectional shape of the bond magnet portion in a cross section perpendicular to the rotation axis of the rotor is a U-shape.
11. 2. The electric motor element according to claim 1, wherein a cross-sectional shape of the bond magnet portion in a cross section in a direction perpendicular to the rotation axis of the rotor is an arc shape.
12. The electric motor element according to claim 1, wherein a lower limit value of a thickness dimension of the bond magnet portion in a cross section in a vertical direction with respect to the rotation axis of the rotor is 2 mm.
13. The electric motor element according to claim 1, wherein the diameter of the rotor ranges from 30 mm to 60 mm.
14. A part of each of the plurality of d-axis magnetic flux paths and a part of each of the plurality of q-axis magnetic flux paths include a laminate in which a plurality of steel sheets are laminated. The electric motor element according to claim 1, comprising Si having an upper limit of 8 wt%.
15. The electric motor element according to claim 1, wherein the laminate included in the rotor includes a configuration in which the ground surfaces of the steel plates are in contact with each other.
16. 2. The electric motor according to claim 1, wherein the laminate included in the rotor includes a configuration in which the ground surfaces of the steel plates are in contact with each other and a configuration in which the ground surfaces of the steel plates are in contact with each other through an oxide film formed by natural oxidation. element.
17. The electric motor element according to claim 1, wherein the laminated body included in the rotor includes a steel plate having a lower limit value of a thickness dimension of 0.35 mm.
18. The electric motor element according to claim 1, wherein the rotor includes a coating covering a surface of the rotor.
19. The stator includes a substantially cylindrical yoke portion, a core of the stator having a plurality of tooth portions extending inside the yoke portion, and an insulation wound around each of the plurality of tooth portions. Including a wire wound body,
    The electric motor element according to claim 1, wherein the core of the stator includes a laminate of electromagnetic steel sheets.
20. An electric motor comprising: the electric motor element according to claim 1; an output shaft that outputs rotational torque of the electric motor element; and a bearing that rotatably supports the output shaft.
21. An apparatus comprising: the electric motor element according to claim 1; an electric motor including an output shaft that outputs rotational torque of the electric motor element; and a bearing that rotatably supports the output shaft.

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