Embedded magnet rotor and rotating electric machine

Abstract

The present invention provides an embedded magnet rotor with a pseudo-Halbach array that is easier to manufacture than conventional designs while suppressing torque reduction. [Solution] An embedded magnet rotor has multiple magnetic poles formed in the circumferential direction of an iron core, and each of the magnetic poles has a magnet arranged thereon, which consists of a first rectangular section and a second rectangular section connected by a bent section. The first rectangular section is arranged on the iron core along a direction perpendicular to the d-axis of the magnetic pole center, and the second rectangular section is arranged in pairs on the iron core for each magnetic pole along the q-axis which is perpendicular to the d-axis in terms of electrical angle. The magnetic poles have a first pattern in which the magnetization orientation of the first rectangular section and the second rectangular section are outward, and a second pattern in which the magnetization orientation of the first rectangular section and the second rectangular section are inward. The magnetic poles of the first pattern and the magnetic poles of the second pattern are arranged alternately in the circumferential direction. The second rectangular section of a first pattern magnetic pole and the second rectangular section of a second pattern magnetic pole that are adjacent in the circumferential direction are arranged back to back along the q-axis.

Description

Technical Field

[0001] The present invention relates to an embedded magnet type rotor and a rotating electric machine.

Background Art

[0002] Conventionally, as an example of a rotor applied to a rotating electric machine, various rotors in which magnets are arranged in a Halbach array along the circumferential direction of the rotor have been proposed. In the rotor of the Halbach array, there is an advantage that magnetic flux can be concentrated on one side by devising the orientation direction of the magnets.

[0003] For example, Patent Document 1 discloses a configuration in which a surface magnet type rotor of a Halbach array is reinforced with a carbon fiber composite material (CFRP). In addition, Patent Document 2 discloses a configuration in which an auxiliary magnet is added between the valleys of the spoke-arranged magnets to suppress leakage magnetic flux, and another auxiliary magnet is added on the outer diameter side of the rotor to improve the salient pole ratio.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, in Patent Document 1, pre-magnetized magnets are applied, and the heating temperature is limited so that the magnets are not demagnetized. Therefore, in Patent Document 1, the workability during assembly may deteriorate due to the magnetic force of the pre-magnetized magnets. Furthermore, in Patent Document 1, the temperature conditions when winding CFRP are also limited in order to avoid demagnetization of the magnets, so there is room for improvement in that the manufacturing of the rotor becomes difficult due to these.

[0006] Furthermore, in Patent Document 2, because there is a flux barrier and a bridge between the spoke magnet and the inner diameter auxiliary magnet, magnetic flux may leak from the flux barrier and bridge portion, potentially reducing the torque of the rotating electric machine. Also, in Patent Document 2, because the inner diameter auxiliary magnet is located on the outer side of the spoke magnet's radial inner end, the inner diameter side of the spoke magnet cannot be fully magnetized by post-magnetization.

[0007] The present invention has been made in view of the above circumstances, and provides an embedded magnet rotor with a pseudo-Halbach array that is easier to manufacture than conventional rotors while suppressing torque reduction. [Means for solving the problem]

[0008] One embodiment is an embedded magnet rotor having multiple magnetic poles formed in the circumferential direction of an iron core, wherein a magnet is arranged at each of the magnetic poles, with a first rectangular section and a second rectangular section connected by a bent section. The first rectangular section is arranged on the iron core along a direction perpendicular to the d-axis of the magnetic pole center, and the second rectangular section is arranged in pairs for each magnetic pole on the iron core along the q-axis, which is perpendicular to the d-axis in terms of electrical angle. The magnetic poles have a first pattern in which the magnetization orientation of the first rectangular section and the second rectangular section are outward, and a second pattern in which the magnetization orientation of the first rectangular section and the second rectangular section are inward. The magnetic poles of the first pattern and the magnetic poles of the second pattern are arranged alternately in the circumferential direction. The second rectangular sections of circumferentially adjacent first pattern magnetic poles and second rectangular sections of second pattern magnetic poles are arranged back-to-back along the q-axis.

[0009] In one embodiment described above, the magnetization orientation of the first rectangular portion and the second rectangular portion of the magnet may be parallel, and the magnetization orientation of the bent portion may be radial.

[0010] In one embodiment described above, the magnet has a shape in which one first rectangular section and one second rectangular section are connected by a bent section, and a pair of magnets may be arranged around the d-axis at each magnetic pole.

[0011] In one embodiment described above, the magnet has a shape in which a second rectangular section is connected to both ends of a first rectangular section via bent sections, and one magnet may be placed at each magnetic pole. Furthermore, in one embodiment described above, an annular reinforcing member may be arranged on the outer circumferential surface of the iron core.

[0012] In one embodiment described above, each magnetic pole may have an auxiliary magnet on the iron core located on the outer circumference of the first rectangular portion. Another embodiment of a rotating electric machine comprises a stator and an embedded magnet type rotor according to one of the above embodiments. [Effects of the Invention]

[0013] According to one embodiment, it is possible to provide an embedded magnet rotor with a pseudo-Halbach array that is easier to manufacture than conventional rotors while suppressing torque reduction. [Brief explanation of the drawing]

[0014] [Figure 1] This is a cross-sectional view of the rotating electric machine according to the first embodiment. [Figure 2] This figure shows an example of the rotor configuration in the first embodiment. [Figure 3] This figure shows the magnets of the rotor in the first embodiment. [Figure 4] This figure shows the magnetization orientation of the rotor in the first embodiment. [Figure 5] (a) is a diagram showing the waveform of the gap magnetic flux density of a surface magnet rotor, (b) is a diagram showing the waveform of the gap magnetic flux density of a surface magnet rotor with a Halbach array, and (c) is a diagram showing the waveform of the gap magnetic flux density of an embedded magnet rotor according to the embodiment. [Figure 6] This figure shows an example of a method for magnetizing magnets in a rotor. [Figure 7] This figure shows an example of the rotor configuration in the second embodiment. [Figure 8] This figure shows the magnets of the rotor in the second embodiment. [Figure 9] This figure shows an example of the rotor configuration in the third embodiment.

Best Mode for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiments, for the sake of easy understanding, the structures and elements other than the main part of the present invention will be described in a simplified or omitted manner. Also, in the drawings, the same elements are denoted by the same reference numerals. Note that the shapes, dimensions, etc. of the elements shown in the drawings are schematically shown and do not represent the actual shapes, dimensions, etc.

[0016] Also, in the following description, the direction parallel to the extension direction of the rotation axis Ax of the rotating electrical machine is referred to as the axial direction, the circumferential direction centered on the rotation axis Ax is simply referred to as the circumferential direction, and the radial direction centered on the rotation axis Ax is simply referred to as the radial direction.

[0017] <First Embodiment> FIG. 1 is a cross-sectional view showing a cross-section in a direction orthogonal to the rotation axis Ax of the rotating electrical machine according to the first embodiment. The rotating electrical machine 1 shown in FIG. 1 is, for example, an inner rotor type motor, and has a rotor 2 which is an example of an embedded magnet type rotor, and a cylindrical stator 3 disposed on the outer periphery of the rotor 2. In FIG. 1, the extension direction of the rotation axis Ax of the rotating electrical machine 1 is perpendicular to the paper surface.

[0018] The stator 3 houses the rotor 2 with an air gap interposed in the central space portion centered on the rotation axis Ax. On the inner peripheral side of the stator 3, a plurality of teeth 3a protruding radially inward toward the rotation axis Ax are provided at equal intervals in the circumferential direction. Slots 3b are formed between adjacent teeth 3a. Coils (not shown) are mounted in the slots 3b of the stator 3 along the outer periphery of the rotor 2.

[0019] In the rotating electrical machine 1, by sequentially switching the magnetic field of the stator 3 by controlling the current of the coil, the rotor 2 rotates about the rotation axis Ax due to the attractive force or repulsive force with the magnetic field of the rotor 2.

[0020] The rotor 2 has an iron core 4, a shaft 5, and a magnet 6. The iron core 4 of the rotor 2 is, for example, a cylindrical member formed by stacking punched silicon steel sheets in the axial direction. An insulating layer is interposed between the individual silicon steel sheets that make up the iron core 4, so that the individual silicon steel sheets are insulated from each other. A shaft 5 is fitted into the axial center of the iron core 4 along the rotation axis Ax. In the rotating electric machine 1, the shaft 5 is rotatably supported by a bearing (not shown).

[0021] Multiple magnets 6 are arranged in a predetermined configuration on the iron core 4 of the rotor 2 such that multiple magnetic poles are formed at equal intervals along the circumferential direction. Adjacent magnetic poles in the circumferential direction of the rotor 2 have opposite polarities. In the first embodiment, a rotor 2 with eight magnetic poles formed in the circumferential direction is shown, but the number of magnetic poles of the rotor 2 is not limited to the above.

[0022] Figure 2 is an enlarged view showing an example of the configuration of the rotor 2 in the first embodiment. Figure 3 is a diagram showing the magnet 6 of the rotor 2 in the first embodiment. Figure 4 is a diagram showing the magnetization orientation of the rotor 2 in the first embodiment.

[0023] The iron core 4 of the rotor 2 has magnet holes extending in the axial direction, and magnets 6 extending in the axial direction are fitted into each magnet hole. As shown in Figure 2, a pair of V-shaped bent magnets 6 are arranged symmetrically around the d-axis (the axis connecting the axis of rotation and the center of any magnetic pole that generates magnetic torque) at one magnetic pole of the rotor 2.

[0024] As shown in Figure 3(b), each magnet 6 has a shape in which, when viewed from the axial direction, it integrally comprises two rectangular sections 6a that form a rectangular parallelepiped and an arc-shaped bent section 6b connecting the two rectangular sections 6a. The thickness t of the magnet 6 is constant in the rectangular sections 6a and the bent section 6b. For example, the lengths of the two rectangular sections 6a are formed to be the same, but the lengths of the two rectangular sections 6a may be different.

[0025] The rectangular portion 6a of the magnet 6 is in a parallel orientation, where the magnetization orientation is uniformly aligned in the thickness direction of the magnet 6 (the short axis direction of the rectangular portion 6a). On the other hand, the bent portion 6b of the magnet 6 is in a radial orientation, where the magnetization orientation at each position is oriented toward the center of curvature of the bent portion 6b.

[0026] As shown in Figure 2, at one magnetic pole of the rotor 2, each magnet 6 is positioned such that one rectangular portion 6a extends along a direction perpendicular to the d-axis, and the other rectangular portion 6a extends along the q-axis (an axis perpendicular to the d-axis in terms of electrical angle). One rectangular portion 6a is an example of a first rectangular portion, and the other rectangular portion 6a is an example of a second rectangular portion.

[0027] Furthermore, the magnet holes in the iron core 4 of the rotor 2 are formed to be partially connected to the magnet holes of adjacent magnetic poles in the circumferential direction along the q-axis. The magnets 6 of adjacent magnetic poles in the circumferential direction are arranged on the iron core 4 such that the rectangular portion 6a on the other side of the magnet 6 is in contact back-to-back along the q-axis.

[0028] Furthermore, at each magnetic pole of the rotor 2, a bridge portion 4a is formed on the d-axis of the iron core 4, connecting the inner and outer circumferences of the iron core between a pair of magnets 6. Also, on the q-axis of the iron core, a flux barrier portion 4b is formed at the outer circumference of the iron core, connected to the magnet holes along the q-axis. Note that in the rotor 2, the flux barrier portion 4b may be omitted, and the outer circumferences of the iron core 4 may be connected between adjacent magnetic poles.

[0029] Furthermore, as shown in Figure 4, in the rotor 2 of this embodiment, the magnetization orientation of the single-pole magnet 6 can be one of two patterns. In the first pattern, both the magnetization orientation of the other rectangular portion 6a positioned along the q-axis and the magnetization orientation of the one rectangular portion 6a positioned along the direction perpendicular to the d-axis are directed outwards from the pole. On the other hand, in the second pattern, both the magnetization orientation of the other rectangular portion 6a positioned along the q-axis and the magnetization orientation of the one rectangular portion 6a positioned along the direction perpendicular to the d-axis are directed inwards from the pole. The first and second patterns of poles are arranged alternately in the circumferential direction of the rotor 2. In Figure 4, the magnetization orientation at each position is indicated by a white arrow.

[0030] As a result, in the rotor 2 of this embodiment, the magnetic poles of the first pattern and the magnetic poles of the second pattern are arranged in the circumferential direction, forming a pseudo-Halbach array in which the magnetization orientation of the magnet 6 changes sequentially by approximately 90° along the circumferential direction. The Halbach array has the characteristic that sinusoidal magnetic flux is concentrated on the outer circumference side of the rotor 2, and almost no magnetic flux is generated on the inner circumference side on the opposite side, thereby further improving the magnetic field strength on the outer circumference side of the rotor 2.

[0031] Specifically, at the q-axis position at the boundary between the first and second magnetic pole patterns, the magnetization orientation of two back-to-back magnets is to the right. At the d-axis position of the second magnetic pole, the magnetization orientation of the magnet is upward (from the inner circumference to the outer circumference). Also, at the q-axis position at the boundary between the second and first magnetic pole patterns, the magnetization orientation of two back-to-back magnets is to the left. Also, at the d-axis position of the first magnetic pole, the magnetization orientation of the magnet is downward (from the outer circumference to the inner circumference). And, at the q-axis position at the boundary between the first and second magnetic pole patterns, the magnetization orientation of two back-to-back magnets is to the right.

[0032] As described above, each magnetic pole in this embodiment is fitted with a V-shaped bent magnet 6. When forming a pseudo-Halbach array, the bent portion 6b of the magnet 6 is located between the other rectangular portion 6a along the q-axis and the rectangular portion 6a along the direction perpendicular to the d-axis, so no magnetic flux leakage occurs between these rectangular portions 6a. Therefore, the rotor 2 of this embodiment can suppress the reduction in torque due to magnetic flux leakage from the above-mentioned location.

[0033] Figure 5(a) shows the waveform of the gap magnetic flux density in a normal surface magnet rotor (SPM). Figure 5(b) shows the waveform of the gap magnetic flux density in a surface magnet rotor (Halbach SPM) in which the magnetization orientation of each magnet is varied in the circumferential direction in a Halbach arrangement. Figure 5(c) shows the waveform of the gap magnetic flux density in the embedded magnet rotor (pseudo-Halbach IPM) of this embodiment. In each figure of Figure 5, the vertical axis represents magnetic flux density [pu] and the horizontal axis represents electrical angle [deg.].

[0034] The waveform of the gap magnetic flux density in this embodiment, shown in Figure 5(c), approximates the waveform of the gap magnetic flux density in the Halbach array shown in Figure 5(b), and shows a shape closer to a sine wave than the waveform of the gap magnetic flux density of a normal surface magnet rotor shown in Figure 5(a). Furthermore, comparing the waveforms in Figure 5(b) and Figure 5(c), it can be seen that the configuration of this embodiment improves the magnetic flux density near the pole center, resulting in a waveform in Figure 5(c) that is less distorted and closer to a sine wave.

[0035] Figure 6 shows an example of a magnetization method for the magnets 6 in the rotor 2 of this embodiment. In the rotor 2 of this embodiment, the iron core 4 is located on the outer circumference side of the magnets 6, and there are no other magnets that would hinder magnetization or air gaps that would obstruct the flow of magnetic flux in the iron core 4. Therefore, in this embodiment, the magnetization device 10 is placed at the d-axis position on the outer circumference of the rotor 2, and each magnet 6 can be completely magnetized with the desired magnetization orientation by the magnetic flux of the magnetization device 10. By post-magnetizing each magnet 6 with the magnetization device 10, the assembly work of the rotor 2 can be made easier.

[0036] As described above, in this embodiment, the rotor 2 has multiple magnetic poles formed in the circumferential direction of the iron core 4, and a magnet 6 is arranged at each magnetic pole, with one rectangular portion 6a and the other rectangular portion 6a connected by a bent portion 6b. The rectangular portion 6a on one side is arranged on the iron core 4 along a direction perpendicular to the d-axis of the magnetic pole center, and the rectangular portion 6a on the other side is arranged in pairs for each magnetic pole on the iron core 4 along the q-axis, which is perpendicular to the d-axis in terms of electrical angle. The magnetic poles have a first pattern in which the magnetization orientation of each rectangular portion 6a is outward, and a second pattern in which the magnetization orientation of each rectangular portion 6a is inward, and the first pattern magnetic poles and the second pattern magnetic poles are arranged alternately in the circumferential direction. Furthermore, the other rectangular portion 6a of the first pattern magnetic pole and the other rectangular portion 6a of the second pattern magnetic pole that are adjacent in the circumferential direction are arranged back to back along the q-axis.

[0037] In this embodiment, the magnetization orientation of the magnets 6 in the circumferential direction of the rotor 2 forms a pseudo-Halbach array, so that sinusoidal magnetic flux is concentrated on the outer circumference of the rotor 2 and the magnetic flux density near the pole center can be improved. Furthermore, in this embodiment, since the magnet 6 bent in a V-shape via the bent portion 6b is used as the magnetic pole, the reduction in torque caused by magnetic flux leakage from between the rectangular portions 6 can be suppressed. Furthermore, in this embodiment, the magnets 6 can be post-magnetized via the iron core 4 at each magnetic pole, making the manufacturing of the rotor 2 easier.

[0038] <Second Embodiment> Figure 7 shows an example of the configuration of the rotor 2 in the second embodiment. Figure 8 shows the magnet 6 of the rotor 2 in the second embodiment. In the following descriptions of each embodiment, elements common to the first embodiment described above will be denoted by the same reference numerals, and redundant explanations will be omitted as appropriate.

[0039] The rotor 2 of the second embodiment is a modification of the first embodiment, in which one U-shaped magnet 6 is placed on each magnetic pole. The magnet 6 used in the second embodiment, as shown in Figure 8, has a shape in which, when viewed from the axial direction, the rectangular portion 6a on one side is connected to both ends of the rectangular portion 6a on the other side via bent portions 6b.

[0040] Furthermore, as shown in Figure 8(b), each rectangular portion 6a has a parallel orientation in which the magnetization orientation is uniformly aligned in the thickness direction of the magnet 6 (the short axis direction of the rectangular portion 6a). On the other hand, the bent portion 6b of the magnet 6 has a radial orientation in which the magnetization orientation at each position is oriented toward the center of curvature of the bent portion 6b. In the magnet 6 of the second embodiment, the thickness t of the magnet 6 is constant in the rectangular portion 6a and the bent portion 6b. Also, one rectangular portion 6a extending in the direction perpendicular to the d axis is formed to be longer than each rectangular portion 6a on the other side that extends along the q axis.

[0041] In the second embodiment, at each magnetic pole of the rotor 2, the rectangular portion 6a on one side of the magnet 6 is arranged to extend perpendicular to the d-axis, and the rectangular portion 6a on the other side is arranged to extend along the q-axis. In the second embodiment as well, each magnet 6 is arranged to alternately form a first pattern of magnetic pole and a second pattern of magnetic pole in the circumferential direction. The rectangular portion 6a on the other side of adjacent first pattern magnetic poles and the rectangular portion 6a on the other side of second pattern magnetic poles are arranged back-to-back along the q-axis. As a result, the rotor 2 in the second embodiment also forms a pseudo-Halbach arrangement similar to that of the first embodiment, and has the same effects as the first embodiment.

[0042] In the rotor 2 of the second embodiment, the outer core 4c and the inner core 4 are separated by the magnet 6, so that a bridge portion (4a) extending along the d-axis is not formed. Therefore, in the second embodiment, magnetic flux leakage to the inner side of the core 4 is further suppressed compared to the first embodiment.

[0043] On the other hand, in order to fix the substantially trapezoidal iron core 4c and magnets 6 on the outer circumference, an annular reinforcing member 7 is arranged on the outer circumference of the iron core 4 in the second embodiment. The reinforcing member 7 is formed, for example, from a sheet of CFRP. Here, the magnets 6 of the rotor 2 in the second embodiment can be post-magnetized in the same manner as in the first embodiment after the reinforcing member 7 has been formed by winding CFRP around them. Therefore, in the second embodiment, the CFRP of the reinforcing member 7 can be wound around the iron core 4 under appropriate temperature conditions without considering the demagnetization of the magnets 6, making the manufacturing of the rotor 2 easier.

[0044] <Third Embodiment> Figure 9 shows an example of the configuration of the rotor 2 in the third embodiment. The rotor 2 of the third embodiment is a modification of the first embodiment, in which auxiliary magnets 8 are arranged on the d-axis of each magnetic pole. The auxiliary magnets 8 are rectangular magnets arranged on the outer core 4 of a pair of magnets 6, and are positioned to extend in a direction perpendicular to the d-axis in a plane perpendicular to the axial direction. The magnetization orientation of the auxiliary magnets 8 is the same as the magnetization orientation of the other rectangular portion 6a of the pair of magnets 6, which is arranged along the direction perpendicular to the d-axis. Note that the auxiliary magnets 8 are not limited to the illustrated example, and arc-shaped magnets, V-shaped magnets, etc., may also be used.

[0045] According to the third embodiment, by additionally embedding auxiliary magnets 8 in the outer core 4, the magnetic torque is increased, and the reluctance torque is also increased by improving the salient polarity of the rotor 2. As a result, the rotating electric machine 1 to which the rotor 2 of the third embodiment is applied can have higher torque than the first embodiment. Alternatively, the auxiliary magnets 8 may be placed on the rotor 2 of the second embodiment shown in Figure 7.

[0046] The present invention is not limited to the embodiments described above, and various improvements and design modifications may be made without departing from the spirit of the invention.

[0047] In the above embodiment, the case where the rotating electric machine 1 is a motor was described, but the embedded magnet rotor of the present invention may also be applied to the rotor of a generator.

[0048] Furthermore, although the above embodiment describes an example in which the rectangular portion 6a and the bent portion 6b of the magnet 6 are formed integrally, the rectangular portion 6a and the bent portion 6b may be formed separately and then integrated by adhesive or other means to form the magnet 6. In addition, in the above embodiment, the tip of the iron core 4 at the location where the rectangular portions 6a are arranged back-to-back along the q-axis may be chamfered to form a curved (rounded) surface, or stress relief grooves may be formed in the iron core 4 by expanding the corners of the magnet hole in the iron core 4 in the circumferential or radial direction.

[0049] Furthermore, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0050] 1...Rotating electric machine, 2...Rotor, 3...Stator, 4,4c...Core, 4a...Bridge section, 4b...Flux barrier section, 5...Shaft, 6...Magnet, 6a...Rectangular section, 6b...Bent section, 7...Reinforcement member, 8...Auxiliary magnet, 10...Magnetic device

Claims

1. An embedded magnet type rotor having multiple magnetic poles formed in the circumferential direction of the iron core, Each of the aforementioned magnetic poles is fitted with a magnet in which a first rectangular section and a second rectangular section are connected by a bent section. The first rectangular portion is positioned on the iron core along the direction perpendicular to the d-axis of the magnetic pole center, The second rectangular portion is arranged in pairs for each magnetic pole on the iron core along the q axis which is perpendicular to the d axis in terms of electrical angle, The magnetic poles have a first pattern in which the magnetization orientation of the first rectangular portion and the second rectangular portion are directed outward, and a second pattern in which the magnetization orientation of the first rectangular portion and the second rectangular portion are directed inward. The first pattern of magnetic poles and the second pattern of magnetic poles are arranged alternately in the circumferential direction. The second rectangular portion of the first pattern of magnetic poles and the second rectangular portion of the second pattern of magnetic poles that are adjacent in the circumferential direction are arranged back-to-back along the q-axis. Embedded magnetic rotor.

2. The magnet is such that the magnetization orientation of the first rectangular portion and the second rectangular portion are parallel, and the magnetization orientation of the bent portion is radial. The embedded magnet type rotor according to claim 1.

3. The magnet has a shape in which one first rectangular portion and one second rectangular portion are connected at the bent portion. A pair of magnets are arranged around the d-axis at each of the aforementioned magnetic poles. The embedded magnet type rotor according to claim 2.

4. The magnet has a shape in which the second rectangular portion is connected to both ends of one of the first rectangular portions via the bent portions, One of the magnets is placed at each of the aforementioned magnetic poles. The embedded magnet type rotor according to claim 2.

5. An annular reinforcing member is arranged on the outer circumferential surface of the iron core. The embedded magnet type rotor according to claim 4.

6. Each magnetic pole has an auxiliary magnet on the iron core located on the outer circumference of the first rectangular portion. The embedded magnet type rotor according to claim 1.

7. Stator and, The embedded magnet rotor according to any one of claims 1 to 6 and A rotating electric machine equipped with the following features.

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