JP2002223538A - Rotor for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor having high workability by reducing noises and vibrations due to cogging torque developed by a motor. SOLUTION: This motor, including a rotor inside a stator, is an inward- rotating motor and comprises recessed accommodation holes, extending to the outer periphery of the rotor with the shaft hole of the rotor taken as its center. Permanent magnets are embedded in the recessed accommodation holes. There are provided clearances between the ends of the recessed accommodation holes and the outer periphery of the rotor, which are formed into recessed shapes. The cogging torque can be reduced, by dividing the rotor into a plurality of sections in the layering direction and displacing the recessed clearances by a prescribed angle in the circumferential direction of the rotor to reduce noises and vibrations. The rotor can be polarized with the stator assembled into a housing taken as a polarized yoke, thereby facilitating handling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor for a motor used in industrial equipment, office equipment, and home electric appliances.

[0002]

2. Description of the Related Art In recent years, permanent magnet type electric motors using permanent magnets have been generally used in electric motors used for industrial equipment, office equipment and home electric appliances. For a rotor of a permanent magnet type electric motor, various types of rotor structures using magnet torque due to the amount of magnetic flux of a permanent magnet and a magnetic flux path inside the rotor and utilizing reluctance torque have been proposed. Conventionally, when improving motor performance,
Although the performance of the material of the permanent magnet embedded in the rotor has been improved and the amount of the permanent magnet used has been increased, there has been a limit in cost and structure of the rotor.

In order to solve this problem, a rotor as shown in FIG. 8 has been proposed. FIG. 8 shows a permanent magnet embedded type rotor used in a three-phase four-pole electric motor.
Are arranged to be different polarities. In a rotor core 1 centered on a rotor shaft hole 5, a housing hole 2 for inserting a permanent magnet 4 is arranged in an arc shape opposite to the outer periphery of the rotor. A gap 3 is provided near the outer periphery of the rotor of the arc-shaped accommodation hole 2. The air gap 3 is formed large in the direction of the center of the magnetic pole in order to concentrate the magnetic flux generated by the permanent magnet 4 in the d-axis direction shown in the drawing. As a result, the magnetic flux concentrates at the center of the magnetic pole, and the magnetic flux in the non-energized section viewed from the control side of the motor can be concentrated in the energized section. ing.

[0004]

However, in such a motor, the magnetic flux can be concentrated to improve the performance of the motor, but the difference in the flow of the magnetic flux between the respective poles becomes very large and the difference between the magnetic poles due to the cogging torque of the motor results. Noise, vibration, etc. are generated.

[0005] In particular, when the output of the motor is large and overloaded, sounds, vibrations, and the like resulting from the cogging torque of the motor appear remarkably.

In addition, the air gap 3 provided in the vicinity of the outer periphery of the rotor in the housing hole 2 in which the permanent magnet 4 is inserted into the rotor core 1 in the motor, particularly in a large-sized motor, concentrates the magnetic flux at the center of the magnetic pole and faces the center of the magnetic pole. The width of the yoke between the air gap 3 and the outer periphery of the rotor is very narrow and narrow so that the magnetic flux does not leak.
Depending on the handling at the time of manufacturing the rotor, the outer periphery of the rotor at the yoke portion is deformed, and the gap between the rotor and the inner diameter of the stator becomes uneven, which is an important problem in quality. This manifests itself as noise, vibration, etc., due to the deterioration of the motor performance and the cogging torque of the motor.

[0007]

SUMMARY OF THE INVENTION An adduction type electric motor having a rotor inside a stator, wherein the rotor has a recessed accommodation hole in which a permanent magnet is embedded, and a shaft hole of the rotor. The end of the concave-shaped receiving hole is formed to extend to the outer periphery of the rotor with the center as the center, and a gap is provided between the end of the concave-shaped receiving hole and the outer periphery of the rotor. This can be achieved by using a rotor of an electric motor in which a shape gap is formed.

In addition, the present invention can be attained by connecting the concave-shaped space with a concave-shaped accommodation hole for embedding a permanent magnet.

In addition, the rotor is divided into a plurality of parts in the stacking direction, and the recessed receiving hole and the recessed space into which the permanent magnet is inserted are shifted by a predetermined angle in the circumferential direction of the rotor. Can be achieved.

Further, the rotor is divided into a plurality of parts in the stacking direction, so that the concave-shaped accommodating hole into which the permanent magnet is inserted is not shifted, and only the concave-shaped air gap is formed at a predetermined angle in the circumferential direction of the rotor. This can be achieved by using a staggered motor rotor. The same effect can be obtained by extending the concave gap toward the center of the magnetic pole by a predetermined angle.

Further, the present invention can be attained by providing a rotor for an electric motor in which a concave-shaped air gap is displaced in the circumferential direction of the rotor by an angle of 1/2 of a slot pitch of the stator.

Further, the present invention can be attained by providing a rotor of an electric motor disposed opposite to a concentrated winding type stator in which a winding is wound directly on a tooth portion of the stator.

The rotor is provided with a concave receiving hole in which a permanent magnet is embedded, and the end of the concave receiving hole extends around the shaft hole of the rotor to the outer periphery of the rotor. And a gap between the end of the concave-shaped accommodation hole and the outer periphery of the rotor, wherein the gap forms a concave-shaped gap in the rotor of the electric motor. The rotor is magnetized using the stator as a magnetizing yoke after the rotor, which is divided into a plurality of parts and whose concave gap is shifted by a predetermined angle in the circumferential direction of the rotor, is assembled into the housing. Method. For example, after a stator and a rotor are assembled in a hermetic compressor serving as a drive source of a refrigerator, an air conditioner, or the like, the rotor can be magnetized using the stator as a magnetizing yoke.

[0014]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a permanent magnet 4 inside a rotor core 1.
a has a concave-shaped receiving hole 2a for inserting a. The permanent magnet 4a inserted in the adjacent concave-shaped receiving hole 2a has a different pole and forms four poles. A flat permanent magnet in which a permanent magnet 4a is divided into a central bottom portion and a concave-shaped receiving hole side portion is inserted into the concave-shaped receiving hole 2a. A concave space 3a is provided between the concave housing hole 2a and the outer periphery of the rotor. The bottom of the concave-shaped cavity 3a is arranged facing the end of the concave-shaped accommodation hole 2a, and the end of the concave-shaped cavity 3a is arranged toward the outer periphery of the rotor. Accordingly, when viewed from the outer diameter of the rotor, a convex rotor core 6 is formed in which a part of the rotor core 1 protrudes in the rotor inner diameter direction in a convex shape.

The width between the end 3a 'of the concave gap 3a located at the center of the rotor magnetic pole and the outer periphery of the rotor is preferably about 0.35 mm to 2.0 mm, and is fixed to the rotor. The magnetic flux generated between the elements is saturated. The magnetic flux density may be about 2.0T. That is,
The magnetic flux generated by the permanent magnet 4a embedded in the concave-shaped accommodation hole 2a in order to concentrate the magnetic flux at the center of the magnetic pole is forcibly directed to the center of the magnetic pole by the end 3a 'of the concave-shaped gap 3a. Prevents leaks. Thus, the magnet torque that contributes to the performance of the electric motor can be increased, and the total torque can be increased.

The width between the end 3a '' of the concave gap 3a located between the rotor magnetic poles and the outer periphery of the rotor is the same as the above-described concave gap 3a located at the center of the magnetic pole. Of the end 3a ', preferably from 0.35 mm to 2.
The magnetic flux generated between the rotor and the stator is preferably about 0 mm so that the magnetic flux is saturated. Also in this case, the magnetic flux density may be about 2.0T, and the end 3a ″ of the concave space 3a is extended to the gap between the magnetic poles larger than the width of the concave housing hole 2a. Thereby, the reluctance torque can be concentrated near the outer periphery of the rotor in the magnetic path of the rotor core 1 located between the recessed accommodation hole 2a in which the permanent magnet 4a is embedded and the rotor shaft hole 5, and the total torque can be reduced. Can be raised.

The convex rotor core 6 at the center of the concave gap 3a is connected to the ends 3a 'and 3a of the concave gap 3a.
It is wider than the width between a '' and the outer periphery of the rotor. Ends 3a 'and 3a''of this concave-shaped void 3a
The presence of the wider convex rotor core 6 allows the magnetic flux to be changed in a stepwise manner from the gap between the magnetic poles where the reluctance torque is concentrated to the center of the magnetic pole where the magnet torque is concentrated.

This embodiment will be described using a stator core 7 and a rotor core 1 in FIG. Although not shown, a stator winding is mounted in a slot of the stator core 7. The magnetic flux from the stator core 7 enters the stator core 7 again via the rotor core 1. The arrows in the figure indicate the flow of the magnetic flux. This magnetic flux appears as an extremely large magnetic flux between the rotor and the stator when the motor is operated under a high load or when the motor is enlarged. Accordingly, the provision of the convex rotor core 6 allows the magnetic flux to flow in a stepwise manner. That is, the magnetic flux flows toward the center of the magnetic pole through the concave space 3a, so that a sudden change in the magnetic flux does not occur. In this case, the gap width on the end 3a ″ side of the concave-shaped gap 3a on the side between the magnetic poles is set to the end 3 on the center of the magnetic pole.
It is preferable that the width is set wider than the gap width on the a ′ side. This is to prevent the leakage of the magnetic flux to the side between the magnetic poles. Conversely, the gap width on the end 3a 'side of the concave-shaped gap 3a on the magnetic pole center side is set to be smaller than the gap width on the end 3a''side on the side between the magnetic poles. This is to allow the magnetic flux to flow in a stepwise manner toward the magnetic pole center via the.
The convex rotor core 6 is connected to the end 3 of the concave gap 3a.
If the air gap on the a 'side is eliminated and the rotor is connected to the rotor core 1 on the magnetic pole center side, the magnetic flux will flow too much and the motor performance will be degraded.

As another effect, the provision of the convex rotor core 6 allows a part of the magnetic flux from the stator to flow once into the convex rotor core 6 and further to the tooth end of the stator. By returning to 8, the magnetic flux can be flowed in a stepwise manner without suddenly flowing a large magnetic flux, and it is needless to say that a better effect can be obtained by using this method together.

Therefore, by providing the concave-shaped space 3a at the end of the concave-shaped accommodation hole 2a, the magnetic flux is consciously flowed through the convex-shaped rotor core 6 so that a sudden magnetic flux is not generated. Therefore, the performance of the electric motor can be maintained, and the noise and vibration caused by the cogging torque can be reduced.

The presence of the convex rotor core 6 having the concave gap 3a increases the width of the yoke between the concave gap 3a and the outer periphery of the rotor, thereby increasing the strength of the yoke. Can be raised. Therefore, the outer periphery of the rotor is not deformed due to handling during manufacture of the rotor, and the width of the yoke portion between the gap portion of the rotor and the outer periphery of the rotor of the motor, which is particularly large, is elongated. Since the width of the yoke portion is widened, the strength is increased and the handling at the time of manufacturing the rotor becomes easy. The outer diameter of the stator in this embodiment is preferably φ180 to φ120, and the inner diameter is φ.
In the case of 110 to 60, the rated output of the electric motor is preferably about 1 to 5 hp, so that a remarkable effect can be obtained by applying the motor.

Another embodiment will be described with reference to FIG. still,
3 and thereafter, the same components as those of the rotor used in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted. FIG. 3 shows an end of a concave-shaped accommodation hole 2a in which a permanent magnet 4a extending around the rotor is embedded, and a concave-shaped space 3a provided between the concave-shaped accommodation hole 2a and the outer periphery of the rotor. They are connected to form one receiving hole. Thereby, the concave-shaped accommodation hole 2a and the concave-shaped space 3
As a result, the yoke portion of the rotor core 1 provided between the magnetic poles is eliminated, and the magnetic flux from the permanent magnet 4a heading toward the magnetic pole center can be effectively concentrated at the magnetic pole center without leaking.
The yoke portion of the rotor core 1 between the concave accommodation hole 2a and the concave gap 3a described with reference to FIGS. 1 and 2 is as narrow as possible so that the rotor core 1 can be punched. Need not be explained.

Another embodiment will be described with reference to FIG. FIG.
A permanent magnet type rotor provided with a concave void 3a at the end of the concave receiving hole 2a of the rotor core 1 in the thickness direction.
The rotor is divided, stacked, and shifted by a predetermined angle in the circumferential direction. When the rotor is divided into two parts in the stacking direction, a solid line with a concave cavity 3a at the end of the concave accommodating hole 2a into which the upper permanent magnet 4a is inserted is indicated by a solid line, and a predetermined angle A broken hole 3b is provided at the end of the concave receiving hole 2b into which the lower permanent magnet 4b shifted by a distance is inserted. However, the magnetic flux flows into and out of the convex rotor core 6 in a stepwise manner by using the rotor with the convex rotor core 6 of the concave gap 3a shifted by a predetermined angle in the circumferential direction of the rotor. That is, it is possible to reduce the sound and vibration caused by the cogging torque generated in the portion between the magnetic poles of the rotor.

In this case, it is desirable that when the convex rotor cores 6 are shifted by a predetermined angle, they do not overlap in the circumferential direction of the rotor. This means that a magnetic path must be formed to allow the magnetic flux to enter the rotor from the tooth end 8 of the stator and escape the magnetic flux to the tooth end 8 of the stator, but the stacked convex rotor cores 6 overlap. In such a case, the magnetic flux escapes in the axial direction of the rotor core 1, leading to a large decrease in performance.

FIG. 5 shows a permanent magnet type rotor having a concave space 3a at the end of the concave receiving hole 2a of the rotor core 1 as in FIG. Unlike this, the concave-shaped accommodation hole 2a into which the permanent magnet 4a is inserted is arranged without being shifted, and only the concave-shaped gap 3a is arranged shifted by a predetermined angle in the circumferential direction of the rotor.
As described above, the rotor is divided into two parts in the stacking direction, and a rotor having a concave space 3a at an end of a concave housing hole 2a into which an upper permanent magnet 4a is inserted. A concave space 3c shown by a solid line and shifted by a predetermined lower angle.
Only the broken line is shown.

In this case, the concave gap 3a may be shifted by a predetermined angle in the circumferential direction of the rotor without changing the shape of the concave gap 3a, and the gap of the concave gap 3a may be shifted to the center of the magnetic pole. It may be extended to the side. In the former case, it is preferable to set the width of the concave-shaped space 3a so that a part of the space of the concave-shaped space 3c always overlaps. If the rotor is shifted in the circumferential direction so that the gap of the concave-shaped gap 3a and the gap of the concave-shaped gap 3c do not overlap, a large amount of magnetic flux leaks in a portion where the gap does not overlap, and the performance of the motor is reduced. It will make it worse. In the latter case, the stepwise flow of the magnetic flux toward the center of the magnetic pole described with reference to FIGS.
In this case, the magnetic flux flows stepwise from the bottom of the concave-shaped space 3a, that is, the space at the end of the concave-shaped accommodation hole 2a. Therefore, in this case, it is the gap at the bottom of the concave gap 3a that is set narrower than the width of the concave gap 3a ″ on the side between the magnetic poles. In both the former and the latter, it is preferable that the convex rotor cores 6 of the concave voids 3a do not overlap in the stacking direction.

In FIG. 4, since the rotor core 1 is divided into two parts in the laminating direction and laminated, the permanent magnet 4a inserted into the concave-shaped accommodation hole 2a has a rotation when viewed from one magnetic pole. Although six pieces will be inserted in the daughter lamination direction, as shown in FIG. 5, since the concave-shaped accommodation hole 2a is not shifted in the circumferential direction of the rotor, it is only necessary to insert three permanent magnets 4a. . Therefore, the operation of inserting the permanent magnet 4a into the rotor core 1 can be simplified. Also, of course,
Since the number of used permanent magnets 4a is reduced, the processing cost of the material can be reduced. Note that the embodiment shown in FIGS. 4 and 5 is the same regardless of whether the concave receiving holes 2a, 2b are connected to the concave voids 3a, 3b, or 3c, respectively. The effect is obtained.

In FIG. 6, as described with reference to FIGS. 4 and 5, with respect to the rotational angle of the rotor shifted by a predetermined angle in the circumferential direction of the rotor, the rotor thickness is divided into two vertically. Explanation will be given using a child. With respect to the slot pitch of the stator into which the windings of the stator are inserted, the deviation angle of the convex rotor core 6 of the concave cavity 3a provided at the end of the concave accommodation hole 2a is 1 /. By shifting by two pitches, the cogging torque generated in the rotor can be reduced.

A method for reducing the cogging torque of the rotor shown in FIG. 6 will be described with reference to FIG. In FIG. 7A, the vertical axis represents the pulsation cycle T of the cogging torque, and the horizontal axis represents the rotation angle θ of the rotor. Assuming that the cogging torque generated in the upper rotor lamination portion is Tθ1 and the cogging torque generated in the lower rotor lamination portion is Tθ2, the lower rotor is smaller than the cogging torque Tθ1 generated in the upper rotor lamination portion. The cogging torque Tθ2 generated in the laminated portion is reduced by the stator slot pitch 1 /
By relatively shifting the mechanical angle corresponding to two cycles, the cogging torque T generated in the upper rotor lamination portion is obtained.
Cogging torque Tθ2 of opposite phase shifted θ1 by 周期 cycle
Can cancel the cogging torque. FIG. 7B shows a state where the cogging torque generated in the upper and lower rotor lamination portions cancels out.

Although FIGS. 6 and 7 show the case where the rotor thickness is divided into two, the rotor thickness is divided into an even number by dividing the rotor thickness by an even number. Cogging torque can be reduced.

The permanent magnet 4 shown in FIGS.
a, a permanent magnet embedded rotor having a concave space 3a, 3b, or 3c provided between the end of each of the concave receiving holes 2a, 2b into which the a, 4b is inserted and the outer periphery of the rotor. By using an electric motor that is arranged opposite to a concentrated winding type stator in which a winding is wound directly on a portion, sound and vibration caused by cogging torque can be reduced. In particular, the effect is good in the case where the number of slots of the stator is small, such as 6, 9, 12 or the like.

The concave gaps 3a, 3b or 3c shown in FIG. 1 and FIG.
The convex rotor core 6 may have a continuous convex shape or a discontinuous convex shape. Therefore, the concave-shaped space 3a may be not only a concave shape but also an E-shape or a comb shape, and can be achieved by appropriately applying the range without departing from the gist of the present invention.

As described above, in the permanent magnet rotor in which the permanent magnet 4a is embedded in the concave-shaped receiving hole 2a and the concave-shaped space 3a is provided at the end of the concave-shaped receiving hole 2a, Although the description has been given of the rotor divided into a plurality of parts in the stacking direction and relatively displaced by a predetermined angle, the rotor with the permanent magnet embedded therein is sealed, for example, as a drive source for an air conditioner or a refrigerator. When the rotor is magnetized by using the winding of the stator after being incorporated in the machine, usually, when the concave space 3a is not provided at the end of the concave housing hole 2a, a predetermined shape is required. Since the position between the magnetic poles of the stator and the position between the magnetic poles of the rotor are different in the rotor lamination portion shifted by an angle, an opposite magnetizing magnetic field is applied from the back surface of the concave-shaped receiving hole 2a on the magnetic pole side. Therefore, the permanent magnet 4a embedded in the rotor is magnetized. It can not be. Therefore, the rotor cannot be magnetized using the stator incorporated in the hermetic compressor.

However, by providing the recessed gaps 3a, 3b or 3c between the recessed accommodation holes 2a and 2b and the outer periphery of the rotor as described with reference to FIGS. By protruding the side ends of the gaps 3a, 3b or 3c to the side between the magnetic poles on the back surface of the concave-shaped receiving holes 2a and 2b, it is possible to prevent the reverse magnetization magnetic field flowing from the stator to the rotor. The rotor incorporated in the hermetic compressor can be magnetized without any gap between the poles.

[0035]

According to the present invention, there is provided an adduction type electric motor having a rotor inside a stator, comprising a concave receiving hole extending to the outer periphery of the rotor around a shaft hole of the rotor. A permanent magnet is embedded in the rotor, and there is a gap between the end of the concave-shaped receiving hole and the outer periphery of the rotor.By making this gap concave, magnetic flux from the rotor core passes through the stator core. When entering the rotor core again, the magnetic flux changes in and out step by step without causing a sudden change in magnetic flux, thereby maintaining the performance of the motor and reducing the noise and vibration caused by cogging torque. be able to. It is particularly advantageous when the motor is operated under a high load or when the motor is enlarged.

Further, the presence of the concave-shaped air gap allows the magnetic flux of the permanent magnet to be concentrated at the center of the magnetic pole without leaking, and the magnetic path of the reluctance torque can be reliably ensured. Can be raised significantly.

Further, the presence of the convex-shaped rotor core portion having the concave-shaped air gap makes it possible to widen the yoke portion between the concave-shaped air gap and the outer periphery of the rotor, thereby increasing the strength. It becomes possible. Therefore, even in the case of a large-sized motor, the elongated yoke portion between the concave-shaped air gap and the outer periphery of the rotor can be made wider without leaking magnetic flux by forming the concave-shaped air gap. Deformation due to the handling of the motor is reduced, the quality is improved, and no noise or vibration is generated due to the deterioration of the motor performance or the cogging torque.

Further, by connecting the concave-shaped space and the concave-shaped receiving hole for embedding the permanent magnet, the magnetic flux generated by the permanent magnet is not leaked, so that the performance of the motor can be improved.

Further, the rotor is divided into a plurality of parts in the stacking direction, and the concave-shaped air gap is shifted by a predetermined angle in the circumferential direction of the rotor. The magnetic flux flows into and out of the rotor core, resulting in the cogging torque generated between the magnetic poles of the rotor,
Vibration can be reduced. Also, the working efficiency can be reduced because the number of permanent magnets can be reduced by shifting only the recessed space by a predetermined angle in the circumferential direction of the rotor without shifting the recessed housing hole into which the permanent magnet is inserted. And material costs can be reduced.
The same effect as described above can also be obtained by extending the concave gap toward the center of the magnetic pole by a predetermined angle.

Further, the concave-shaped gap of the rotor divided into a plurality in the thickness direction of the rotor is relatively shifted in the circumferential direction of the rotor by an angle of 1/2 of the slot pitch of the stator. As a result, the pulsation periods of the cogging torque generated in the rotor magnetic pole gap portion are in opposite phases to each other, so that the pulsation of the cogging torque can be canceled and the sound, vibration, and the like can be reduced.

Further, by using the rotor according to this method for a concentrated winding type stator in which a winding is wound directly on the teeth of the stator, it is possible to reduce noise and vibration caused by cogging torque.

Further, a concave-shaped accommodation hole extending to the outer periphery of the rotor centering on the shaft hole of the rotor is provided, and a permanent magnet is embedded in the concave-shaped accommodation hole. In the rotor of the electric motor, which has a gap between the outer peripheries and the gap forms a concave shape, the rotor is divided into a plurality in the stacking direction, and the concave gap is formed in the circumferential direction of the rotor. By using a rotor that is shifted by a predetermined angle, the rotor can be magnetized using the stator as a magnetizing yoke after being assembled in the housing, even if the rotor has different pole positions. For example, after the stator and the rotor are incorporated in a hermetic compressor serving as a drive source of a refrigerator or an air conditioner, the rotor can be magnetized using the stator as a magnetizing yoke.

[0043]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rotor showing an embodiment of the present invention.

FIG. 2 is a diagram showing a flow of a magnetic flux in FIG.

FIG. 3 is a cross-sectional view of a rotor showing another embodiment.

FIG. 4 is a cross-sectional view of a rotor showing another embodiment.

FIG. 5 is a cross-sectional view of a rotor showing another embodiment.

FIG. 6 is a partial cross-sectional view of a stator and a rotor showing another embodiment.

FIG. 7 is a pulsation cycle of cogging torque of the rotor structure shown in FIG. 6;

FIG. 8 is a cross-sectional view of a rotor showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotor core, 2, 2a, 2b ... Concave-shaped accommodation hole, 3
... voids, 3a, 3b, 3c ... concave-shaped voids, 3a ', 3
a '',... side end portions of concave voids, 4, 4a, 4b permanent magnets, 5 shaft holes, 6 convex rotor cores, 7 stator iron cores, 8 tooth ends, 9 … Caulking pin.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H02K 21/14 H02K 21/14 MF term (reference) 5H002 AA02 AA05 AB06 AB07 AC06 5H621 AA02 AA04 BB10 GA01 GA12 GA16 HH01 JK02 JK05 5H622 AA02 AA03 CA02 CA07 CA13 CB01 CB05 CB06 PP10 PP11 PP19

Claims (8)

[Claims] 1. An adduction type electric motor having a rotor inside a stator, wherein the rotor has a recessed receiving hole in which a permanent magnet is embedded, and a center of the shaft hole of the rotor is provided. An end of the concave-shaped receiving hole is formed so as to extend to the outer periphery of the rotor, and a gap is provided between the end of the concave-shaped receiving hole and the outer periphery of the rotor, and the void has a concave shape. A rotor for an electric motor, wherein a shape gap is formed. 2. The rotor for an electric motor according to claim 1, wherein the concave-shaped gap is connected to the concave-shaped receiving hole for embedding the permanent magnet. 3. The rotor is divided into a plurality of parts in a stacking direction, and the concave-shaped receiving hole into which the permanent magnet is inserted and the concave-shaped space are formed at a predetermined angle in a circumferential direction of the rotor. 3. The method according to claim 1, wherein the position is shifted.
A rotor for an electric motor according to any one of the above items. 4. The rotor is divided into a plurality of parts in the stacking direction, and only the concave-shaped gap is provided in the circumferential direction of the rotor without shifting the concave-shaped receiving hole into which the permanent magnet is inserted. 3. The rotor for an electric motor according to claim 1, wherein the rotor is shifted by a predetermined angle. 5. The rotor according to claim 1, wherein the rotor is divided into a plurality of parts in the stacking direction, and the recessed space is directed toward the center of the magnetic pole without shifting the recessed housing hole into which the permanent magnet is inserted. 3. The rotor for an electric motor according to claim 1, wherein the rotor is extended by an angle. 6. The method according to claim 3, wherein the concave-shaped gap is shifted in a circumferential direction of the rotor by an angle of １ ／ of a slot pitch of the stator. Electric motor rotor. 7. The motor according to claim 1, wherein the rotor is an electric motor arranged opposite to a concentrated winding type stator in which a winding is wound directly on the teeth of the stator. Or the rotor of the motor as described. 8. An adduction type electric motor having a rotor inside a stator, wherein the rotor has a concave-shaped receiving hole in which a permanent magnet is embedded, and a center of the shaft hole of the rotor is provided. An end of the concave-shaped receiving hole is formed so as to extend to the outer periphery of the rotor, and a gap is provided between the end of the concave-shaped receiving hole and the outer periphery of the rotor, and the void has a concave shape. In the rotor of the electric motor having a shape gap, the rotor is divided into a plurality in the stacking direction, and the concave shape gap is shifted by a predetermined angle in the circumferential direction of the rotor. A magnetizing method using the stator as a magnetizing yoke after being assembled into the rotor.