JP2004140951A - Permanent magnet-embedded motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet-embedded motor which is high in motor efficiency and in productivity. <P>SOLUTION: A rotor 4 comprises a rotor core 10 which is obtained by compression molding magnetic fine particles coated with an insulating film, and a plurality of plate-like magnets 11 buried in the rotor core 10. The magnets 11 are housed in a plurality of housing holes 12 formed in proximity to the periphery of the rotor core 10 at equal angular intervals. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a permanent magnet embedded motor.
[0002]
[Prior art]
2. Description of the Related Art In recent years, there has been an increasing demand for smaller and lighter products in all fields, and a motor as a drive source is also required to have high efficiency capable of meeting the demand.
[0003]
As a high-efficiency motor, there is a permanent magnet embedded motor (hereinafter, IPM motor). The IPM motor is a motor having a rotor in which a magnet is embedded in a rotor core. In addition to a rotating magnetic field generated by the stator and a magnet torque between the rotor, a reluctance torque based on a magnetic path of the rotating magnetic field formed on the rotor surface. By effectively utilizing, high motor efficiency can be obtained.
[0004]
Conventionally, a rotor of an IPM motor is manufactured by forming a slit in a rotor core formed by laminating electromagnetic steel plates and embedding a plate-like magnet in the slit. As a technique for further improving the motor efficiency of such an IPM motor, for example, there is a technique in which an end of a slit is extended to near the outer periphery of a rotor core and gaps are provided at both ends of a magnet (see Patent Document 1).
[0005]
As a result, the gap between both ends of the magnet becomes a non-magnetic portion, demagnetization of the magnet due to magnetic flux between adjacent teeth is suppressed, a stable driving torque can be generated, and the winding is wound with concentrated winding. Increasing the rate can also improve motor efficiency.
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-50543 (FIG. 1)
[0007]
[Problems to be solved by the invention]
However, due to the rotation of the rotor, eddy current loss proportional to the square of the rotation speed of the rotor occurs in the rotor core, and iron loss increases as the rotation speed increases, so that there is an essential problem that motor efficiency is reduced. .
[0008]
Further, since the rotor core of the conventional example is the electromagnetic steel sheet laminated core as described above, it is difficult to match the width of the slit with the thickness of the inserted magnet with high accuracy. However, if the width of the slit is formed to be larger than the thickness of the magnet in consideration of the workability at the time of inserting the magnet, both inner wall surfaces orthogonal to the radial direction of the slit and outer surfaces which are both side surfaces on the magnetic flux direction side of the magnet. In addition, there is a problem that a gap, which is a non-magnetic portion, is formed between the inner surface and the inner surface, and a magnetic flux loss occurs.
[0009]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a permanent magnet embedded motor having high motor efficiency and high productivity.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 includes a stator core having a plurality of teeth wound around a winding and extending toward an axial center, a rotor core, and a plate-shaped embedded in the rotor core. And a rotor rotatably accommodated inside the stator core having a plurality of magnets, wherein the rotor core is formed by compression molding magnetic powder coated with an insulating film. The main point is to do.
[0011]
The gist of the invention described in claim 2 is that the both sides of the magnet in the magnetic flux direction are in close contact with the rotor core.
According to a third aspect of the present invention, in the rotor, the magnets are arranged in a mold, and the magnets and the rotor core are integrally formed.
[0012]
Further, the invention according to a fourth aspect is characterized in that the magnets are press-fitted and fixed in accommodation holes formed in the rotor core.
The gist of the invention described in claim 5 is that the magnetic powder has a resin film layer on the outermost shell.
[0013]
(Action)
According to the first aspect of the present invention, since the eddy current loop generated with the rotation of the rotor core is completed in the magnetic powder, the eddy current loop is shortened and the eddy current loss is reduced. As a result, an increase in iron loss in the high rotation region is suppressed, and the motor efficiency is improved. Further, since the rotor core is manufactured by compression molding, workability is high and molding accuracy is high, so that productivity of the rotor is improved.
[0014]
According to the second aspect of the present invention, since both side surfaces of the magnet in the magnetic flux direction are in close contact with the rotor core, there is no gap serving as a non-magnetic portion in the magnetic flux direction of the magnet, and there is little magnetic flux loss, thereby improving motor efficiency. .
[0015]
According to the third aspect of the present invention, since the rotor core and the magnet are formed integrally, there is no gap in the magnetic flux direction of the magnet that becomes a non-magnetic portion, so that magnetic flux loss is prevented, and as a result, motor efficiency is reduced. improves. In addition, since they are manufactured at once using a mold, the work process is greatly simplified, and the productivity is improved.
[0016]
According to the fourth aspect of the present invention, since the molding accuracy of the accommodation hole is high, the press-fitting operation is easy, and the productivity is improved. Further, since each magnet and the rotor core are in close contact with each other, there is no gap in the direction of the magnetic flux of the magnet that becomes a non-magnetic portion. As a result, magnetic flux loss is prevented, and motor efficiency is improved.
[0017]
According to the fifth aspect of the present invention, since the outermost resin film layer serves as a protective film, the effect of suppressing eddy current loss due to damage to the insulating film layer during compression molding is prevented. Further, since the resin film layer of the outermost shell layer serves as a binder, there is no need to mix a binder or the like other than the magnetic powder, thereby improving productivity.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment in which the present invention is embodied in a permanent magnet embedded motor (hereinafter, IPM motor) will be described with reference to FIGS.
[0019]
As shown in FIGS. 1 and 2, the IPM motor 1 includes a stator core 3 fixed to an inner periphery of a substantially bottomed cylindrical case 2 and a rotor 4. The stator core 3 has a plurality of teeth 5 arranged at equal angular intervals on the inner periphery thereof, and each of the teeth 5 extends from the inner periphery of the stator core 3 toward the center. In the present embodiment, 24 teeth 5 are provided at intervals of 15 °. A core winding 7 is wound around each tooth 5 via an insulator 6. In FIG. 2, the insulator 6 and the core winding 7 are omitted. In the present embodiment, the core winding 7 is distributedly wound around the teeth 5 having a central angle of 90 ° with respect to each other, and the core winding 7 has three phases with a phase difference of 120 °. An alternating current is supplied.
[0020]
The rotor 4 includes a rotor core 10, and a plate-shaped magnet 11 is embedded in the rotor core 10. In the present embodiment, the rotor core 10 is formed by compression molding magnetic powder coated with an insulating film. In the vicinity of the outer periphery of the rotor core 10, a plurality (four) of accommodation holes 12 penetrating the rotor core 10 in the axial direction are formed at equal angular intervals (90 °). Each of the housing holes 12 extends toward both sides in a direction orthogonal to the radial direction of the rotor core 10 to the vicinity of the outer periphery of the rotor core 10, and each magnet 11 is housed in each of the housing holes 12.
[0021]
As shown in FIGS. 3 and 4, each magnet 11 is arranged such that the inner side surface 11 a or the outer side surface 11 b of the magnet 11 becomes an N pole or an S pole so that the direction of the magnetic flux coincides with the radial direction of the rotor core. Have been. The magnets 11 are arranged such that the magnetic poles of the adjacent magnets 11 are alternately reversed (for example, the magnets 11 on both sides of the magnet 11 whose outer surface 11b is the N pole have the outer surface 11b of the S pole). It is accommodated in the accommodation hole 12.
[0022]
Each accommodation hole 12 has a width (radial length) W1 of a portion in which the magnet 11 is accommodated, and a thickness (radial length, that is, a length from the inner surface 11a to the outer surface 11b of the magnet 11) of each magnet 11. (Length) W2. Each magnet 11 has its inner side surface 11a and outer side surface 11b in close contact with both inner wall surfaces 12a, 12b orthogonal to the radial direction of each accommodation hole 12, and is fixed in each accommodation hole 12. Therefore, there is no gap between the inner surface 11 a and the outer surface 11 b of each magnet 11, which are both side surfaces on the magnetic flux direction side, and the rotor core 10 in the magnetic flux direction.
[0023]
The length L1 (length in a direction orthogonal to the radial direction) L1 of each of the magnet holes 11 is formed to be longer than the length L2 of each magnet, and both ends of each magnet 11 in the direction orthogonal to the radial direction. A gap 13 is formed near the portions 11c and 11d.
[0024]
As shown in FIG. 1, the rotor 4 has a rotating shaft 16 press-fitted and fixed in a center hole 15 of the rotor core 10, and the rotating shaft 16 is supported by a bearing 18 provided on the case 2 and the lid 17. As a result, it is rotatably supported and accommodated in the case 2 and the lid 17 so as to be surrounded by the stator core 3.
[0025]
Next, a method for manufacturing the rotor 4 of the present embodiment will be described.
As shown in FIG. 5, after the magnets 11 are arranged in the mold 30, the rotor 4 compresses the magnetic powder X filled in the mold 30 to form the rotor core 10 and the magnets 11. It is manufactured by integrally forming.
[0026]
As shown in FIG. 6, the magnetic powder X used in the present embodiment has a structure in which a binder layer B which is a resin film layer is further formed on an insulating film (oxide film) layer I covering the magnetic layer M. It has a layered structure. And the binder layer B which is the outermost shell layer has a function as a binder. That is, when the magnetic powders X are mutually compressed by being pressed in the mold 30, the binder layers B, which are the outermost shell layers of the adjacent magnetic powders X, are pressed together.
[0027]
As shown in FIG. 5, the mold 30 includes a molding die 31 and a pressing die 32. In the present embodiment, the molding die 31 has a cylindrical shape with a bottom, and the pressing die 32 has a cylindrical shape, and is formed such that the outer diameter of the pressing die 32 and the inner diameter of the molding die 31 are substantially the same. The mold 30 can be formed into a desired shape by changing the shapes of the molding die 31 and the pressing die 32.
[0028]
At the center of the bottom surface 33 of the molding die 31, a cylindrical molding core 34 is erected, and the molding core 34 extends in the opening direction of the molding die 31 (upper side in the figure). The end extends above the side wall 35 of the mold 31. On the other hand, a sliding recess 37 having a circular cross section is formed in the center of the bottom surface (the lower surface in the figure, hereinafter referred to as a compression surface 36) of the pressurizing mold 32. The sliding recess 37 has an inner diameter. It is formed so as to have substantially the same outer diameter as the molding core 34. The pressing die 32 is vertically slidable along the molding core 34 by inserting the molding core 34 of the molding die 31 into the sliding recess 37. That is, the mold 30 performs compression molding by moving the pressing mold 32 downward, and strongly pressing the magnetic powder X filled in the molding mold 31 by the compression surface 36 thereof.
[0029]
As shown in FIG. 7, at four locations near the outer periphery of the bottom surface 33 of the molding die 31, positioning portions 42 composed of a pair of columnar molding projections 41 are formed at equal angular intervals (90 °). . At the time of molding, first, four magnets 11 are arranged in a molding die 31. Each magnet 11 is placed upright between the opposing forming projections 41 of these adjacent positioning portions 42 such that both ends 11c and 11d in a direction orthogonal to the radial direction thereof come into contact (see FIG. 8).
[0030]
Next, as shown in FIG. 5, the magnetic powder X is filled into the molding die 31 so as to fill the gaps between the magnets 11 and the side wall portions 35, and the pressing die 32 is slid downward to form the molding die. The magnetic powder X filled in 31 is compressed. That is, thereby, the rotor 4 in which the magnets 11 arranged in the mold 30 and the rotor core 10 made of the compressed magnetic powder are integrally formed is manufactured.
[0031]
The hole formed by removing the molded rotor 4 from the mold 30, that is, the hole where the molding core 34 and the molding protrusion 41 were present at the time of molding, is the portion where the molding core 34 was present. The portion where the center hole 15 and the forming protrusion 41 existed becomes the gap 13 near the both end portions 11c and 11d of each magnet 11.
[0032]
Next, the characteristic effects of the present embodiment will be described below.
(1) The rotor 4 includes a rotor core 10 formed by compression-molding magnetic powder coated with an insulating film, and a plurality of plate-shaped magnets 11 embedded inside the rotor core 10. Each of the magnets 11 is housed in a plurality of housing holes 12 formed at equal angular intervals near the outer periphery of the rotor core 10.
[0033]
Since the rotor core 10 is a magnetic powder compression core manufactured by compression molding of a magnetic powder coated with an insulating film as described above, a problem occurs particularly in a high rotation region of the motor (the winding current is in a high frequency region). Eddy current loss) can be suppressed.
[0034]
In the case of the rotor core 10 of the present embodiment, since each magnetic powder X has the insulating coating layer I, the eddy current loop generated with the rotation of the rotor core 10 is completed in the magnetic layer M of each magnetic powder X. Therefore, the eddy current loop is shorter and the eddy current loss is smaller than in a conventional electromagnetic steel sheet laminated core in which an eddy current loop is generated for each laminated steel sheet.
[0035]
As a result, an increase in iron loss in the high rotation region can be suppressed, and as a result, high motor efficiency can be realized even in the high rotation region. Further, in the case of the magnetic powder compression core, since the production is easy and the molding accuracy is high, the productivity of the rotor can be improved.
[0036]
(2) After arranging the magnets 11 in the mold 30, the rotor 4 compression-molds the magnetic powder X filled in the mold 30 to integrally mold the rotor core 10 and the magnets 11. It is manufactured by doing.
[0037]
Accordingly, in each magnet 11, in the magnetic flux direction, the inner side surface 11 a and the outer side surface 11 b of each magnet 11 are in close contact with the inner wall surfaces 12 a and 12 b of the accommodation hole 12, and there is no gap between the magnet 11 and the rotor core 10. . As a result, it is possible to prevent magnetic flux loss caused by the gap between each magnet and the rotor core 10 becoming a non-magnetic portion, and as a result, it is possible to realize high motor efficiency. In addition, since the compression molding is performed at a time using the mold 30, the working process is greatly simplified, so that the productivity can be improved.
[0038]
(3) The magnetic powder X has a three-layer structure in which a binder layer B which is a resin film layer is further formed on an insulating film (oxide film) layer I covering the magnetic layer M. The binder layer B, which is the outermost shell layer, has a function as a binder, and is pressed in the mold 30 so that the magnetic powders X are mutually compressed, so that the outermost shell of the adjacent magnetic powders X is formed. The binder layers B, which are layers, are pressed together.
[0039]
Therefore, since the binder layer B serves as a protective film, the insulating coating layer I of the magnetic powder X is not damaged even during compression molding, and the effect of suppressing the eddy current loss obtained by using the insulating coating-coated magnetic powder compressed core is obtained. The drop can be prevented. Further, since there is no need to mix a binder for binding the magnetic powders, productivity can be improved.
[0040]
The above embodiment may be modified as follows.
In the present embodiment, after the magnets 11 are arranged in the mold 30, the rotor 4 is filled with the magnetic powder X in the mold 30 and the rotor core 10 is compression-molded to form the rotor 4 together with the magnets 11. It is integrally molded. However, the present invention is not limited to this, and the rotor core 10 having the accommodation holes 12 may be formed, and the magnets 11 may be press-fitted and fixed in the accommodation holes 12.
[0041]
For example, as shown in FIG. 9, the magnetic powder X is compression-molded using a mold 50 for molding the rotor core 10 having the respective accommodation holes 12.
As shown in FIG. 10, on the bottom surface 53 of the molding die 51, four molding plates 55 are erected at equal angular intervals (90 °) in the vicinity of the outer periphery, and are directed toward both sides in a direction perpendicular to the radial direction. Extend. The central portion 55a of each forming plate 55 extends over the length L2 of each of the magnets 11 and is formed so that its thickness (length in the radial direction) becomes the same thickness W3 as the thickness W2 of the magnets 11. I do.
[0042]
Then, as shown in FIG. 9, the magnetic powder X filled in the molding die 31 is compressed by sliding the pressing die 32 downward, and the rotor core 10 having the respective accommodation holes 12 is molded. Each of the magnets 11 is press-fitted and fixed in the accommodation hole 12.
[0043]
Here, since the thickness W3 of the central portion 55a of each forming plate 55 is the same as the thickness W2 of each magnet 11 housed in the rotor core 10, the width W1 of each housing hole 12 in which the magnet 11 is housed is It is the same as the thickness W2 of the magnet 11. Therefore, after each magnet 11 is inserted, the inner side surface 11a and the outer side surface 11b of each magnet 11 and the inner wall surfaces 12a and 12b of each accommodation hole 12 come into close contact with each other and are held in each accommodation hole 12. . That is, since there is no gap serving as a non-magnetic portion in the magnetic flux direction of each magnet 11, no magnetic flux loss occurs due to the gap between each magnet 11 and each accommodation hole 12. Therefore, the magnetic flux loss can be suppressed, and the motor efficiency can be improved.
[0044]
In addition, since the rotor core 10 is a magnetic powder compression core formed by compression-molding magnetic powder, the molding accuracy is high, and at the time of press-fitting, each magnet 11 is inserted into the accommodation hole 12 so as to be stiff. High.
[0045]
The length (length in the direction perpendicular to the radial direction) L3 of each forming plate 55 is set to the length of each magnet 11 (the length in the direction perpendicular to the radial direction, that is, the length between both ends 11c and 11d). C) It may be formed longer than L2.
[0046]
With such a configuration, the length L1 in the direction orthogonal to the radial direction of each accommodation hole 12 formed in the rotor core 10 is orthogonal to the radial direction of each magnet 11 that is press-fitted into each accommodation hole 12. Since the length is longer than the length L2 in the direction, the gaps 13 that become the non-magnetic pole portions are formed at the both end portions 11c and 11d of each magnet 11. Therefore, the rotor 4 that can prevent the demagnetization of each magnet 11 can be manufactured.
[0047]
In the present embodiment, the stator core 3 has 24 teeth 5, but may have other numbers such as 6, 12 or the like.
In the present embodiment, the core winding 7 is wound around the tooth 5 by distributed winding, but may not be 90 °, and may be wound around the tooth 5 by concentrated winding instead of distributed winding. .
[0048]
In the present embodiment, the gaps 13 are formed near the both end portions 11c and 11d of each magnet 11, but the gaps 13 may not be provided. Further, non-magnetic portions other than the gaps may be provided near the both ends 11c and 11d.
[0049]
-In another example, although each magnet 11 was press-fitted and fixed in each accommodation hole 12, each magnet 11 may be fixed by other methods such as bonding after being inserted into each accommodation hole 12.
[0050]
The magnets 11 may be arranged in two or more rows in parallel.
The shape of each magnet 11 may be a flat plate, a curved shape, or another shape.
[0051]
In the present embodiment, a magnetic powder X having a three-layer structure having a binder layer B as a resin film layer on an insulating film (oxide film) layer I covering the magnetic layer M is used. However, the present invention is not limited to this, and a mixed powder of a magnetic powder coated with an insulating film and a binder for bonding the magnetic powder to each other may be used.
[0052]
Next, technical ideas that can be grasped from the above embodiments and other examples will be additionally described below.
(1) The permanent magnet embedded motor according to claim 3, wherein a radial length of each magnet is equal to a radial length of a portion of each housing hole into which each magnet is press-fitted. Features permanent magnet embedded motor.
[0053]
(2) In the permanent magnet embedded motor according to claim 3 or (1), the length of each of the accommodation holes in a direction perpendicular to the radial direction is longer than the length of each magnet in the direction perpendicular to the radial direction. A permanent magnet embedded motor.
[0054]
With such a configuration, a gap is formed near both ends in a direction orthogonal to the radial direction of each magnet, so that the gap becomes a non-magnetic portion, and demagnetization of each magnet due to magnetic flux between the adjacent teeth is suppressed. As a result, a stable driving torque can be generated.
[0055]
(3) In the permanent magnet embedded motor according to any one of (1) to (4), (1) and (2), the rotor has both ends in a direction orthogonal to a radial direction of the magnet. A permanent magnet embedded motor comprising a non-magnetic portion near the portion.
[0056]
(4) A rotor including a rotor core formed by compression molding magnetic powder coated with an insulating film, and a plurality of plate-shaped magnets embedded in the rotor core.
(5) A rotor manufacturing method for manufacturing the rotor according to (4) using a mold having a molding die and a pressure die.
[0057]
(6) In the method of manufacturing a rotor according to (5), a step of arranging the magnets in the mold, a step of filling the gap in the mold with the magnetic powder, and a step of pressing the mold. Compressing the magnetic powder by moving the rotor.
[0058]
(7) In the method of manufacturing a rotor according to (6), each of the magnets is arranged such that the two ends contact a plurality of columnar protrusions formed on the bottom surface of the molding die. And a method for manufacturing a rotor.
[0059]
With such a configuration, the positioning of each magnet is facilitated, so that workability can be improved. In addition, since a gap that is a non-magnetic pole portion is formed at the both ends of each magnet, demagnetization of each magnet can be prevented.
[0060]
(8) The method for manufacturing a rotor according to (5), further comprising: a step of molding the rotor core; and a step of press-fitting the magnet into a plurality of receiving holes formed in the rotor core. Rotor manufacturing method.
[0061]
(9) The method for manufacturing a rotor according to (5) or (8), wherein a plurality of plate-shaped protrusions are provided on a bottom surface of the mold.
[0062]
With such a configuration, the portion where each plate-shaped protrusion is located in the molding step is formed as each of the accommodation holes.
(10) The method for manufacturing a rotor according to (9), wherein each of the plate-shaped protrusions has a portion having a radial length equal to a radial length of each of the magnets. Manufacturing method of the rotor.
[0063]
With such a configuration, each receiving hole formed in the rotor core is formed with a portion whose radial length is the same as the radial length of each magnet pressed into each receiving hole. . Therefore, in such a portion, the magnet and the rotor core are in close contact with each other in the magnetic flux direction of the magnet, and there is no gap that becomes a non-magnetic portion in the magnetic flux direction. As a result, a rotor with small magnetic flux loss can be manufactured.
[0064]
(11) In the method for manufacturing a rotor according to (9) or (10), the length of each of the plate-shaped protrusions in the direction orthogonal to the radial direction is equal to the length of each of the magnets in the direction orthogonal to the radial direction. A method for manufacturing a rotor, comprising:
[0065]
With such a configuration, the length of each of the receiving holes formed in the rotor core in the direction perpendicular to the radial direction is longer than the length of each of the magnets press-fitted into each of the receiving holes in the direction perpendicular to the radial direction. Therefore, a gap is formed at each of the two ends of the magnet to be a non-magnetic pole portion. Therefore, a rotor capable of preventing demagnetization of each magnet can be manufactured.
[0066]
【The invention's effect】
As described above in detail, according to the first to fifth aspects of the present invention, it is possible to provide a permanent magnet embedded motor having high motor efficiency and high productivity.
[Brief description of the drawings]
FIG. 1 is a sectional view of an IPM motor.
FIG. 2 is an AA cross-sectional view of the IPM motor.
FIG. 3 is an enlarged sectional view of a rotor.
FIG. 4 is a sectional view of a rotor near a magnet.
FIG. 5 is an explanatory view of a method for manufacturing a rotor.
FIG. 6 is a sectional view of a magnetic powder.
FIG. 7 is a top view of a molding die on which magnets are arranged.
FIG. 8 is a BB cross section of a molding die on which magnets are arranged.
FIG. 9 is an explanatory view of a method of manufacturing another example of a rotor core.
FIG. 10 is a top view of a molding die of another example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Permanent magnet embedded motor (IPM motor), 3 ... Stator core, 4 ... Rotor, 5 ... Teeth, 7 ... Core winding, 10 ... Rotor core, 11 ... Magnet, 11a ... Inner surface, 11b ... Outer surface, 12 ... Housing Holes, 12a, 12b: inner wall surface, 30, 50: mold, X: magnetic powder, M: magnetic layer, I: insulating layer, B: binder layer.

Claims (5)

A stator core having a plurality of teeth around which windings are wound and extending toward the axial center; a rotor core; and a plurality of plate-shaped magnets embedded in the rotor core, rotatably housed inside the stator core. A permanent magnet embedded motor comprising:
The permanent magnet embedded motor, wherein the rotor core is formed by compression molding magnetic powder coated with an insulating film. The permanent magnet embedded motor according to claim 1,
A permanent magnet embedded motor, wherein both side surfaces of the magnets in the magnetic flux direction and the rotor core are in close contact with each other. The permanent magnet embedded motor according to claim 1 or 2,
The permanent magnet embedded motor, wherein the rotor has the magnets arranged in a mold, and the magnets and the rotor core are integrally formed. The permanent magnet embedded motor according to claim 1 or 2,
The permanent magnet embedded motor, wherein each of the magnets is press-fitted and fixed in a housing hole formed in the rotor core. The permanent magnet embedded motor according to any one of claims 1 to 4,
The permanent magnet embedded motor, wherein the magnetic powder has a resin film layer on the outermost shell.

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