JP2007252018A - Permanent magnet motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet motor which allows a rotor to be provided with a continuous hole, while suppressing the drop of efficiency. <P>SOLUTION: The rotor 10 of the permanent magnet includes magnet insertion holes 11a-11d wherein permanent magnets 12a-12d are to be inserted, the above continuous hole 18, and a rotating shaft insertion hole 19 wherein the rotating shaft 20 is to be inserted. The stator 30 is provided with teeth 32 which form slots 33. The continuous hole 18 is not provided in the first region, which is made of a first boundary that is parallel with a line along an inner wall arranged on the side of the rotating shaft insertion hole 19 more than permanent magnets 12a-12d, out of the walls forming the magnet insertion holes 11a-11d, and is apart by the width of the teeth 32 on the side of the rotating shaft insertion hole 19 from the line along the inner wall, and a line along the inner wall, and a second region which is made of a second boundary that extends in the direction of an adjacent main magnetic pole from the line along the inner wall and a point crossing the axis d of each magnetic pole and whose inclination is based on the ratio of the density of the magnetic flux of the rotor 10 to the density of the magnetic flux of the permanent magnets 12a-12d, and a line along the inner wall. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a permanent magnet motor using a permanent magnet, and more particularly to a permanent magnet motor in which a permanent magnet is inserted into a magnet insertion hole provided in a rotor.

Rotation with permanent magnets inserted into magnet insertion holes as motors that drive compressors (compressors) such as air conditioners (air conditioners) and refrigerators, motors that drive vehicles, and motors that are mounted on vehicles. A permanent magnet motor having a child is used. Such a permanent magnet motor is usually called an “embedded permanent magnet motor (IPM motor)”.
A permanent magnet motor used as an electric motor for driving the compressor (compressor driving electric motor) has, for example, the configuration shown in FIG. FIG. 21 is a cross-sectional view of the permanent magnet motor perpendicular to the axial direction. The permanent magnet motor includes a rotor 910 and a stator 930.
The rotor 910 includes a rotor core (rotor core) 911 formed by laminating electromagnetic steel plates. The rotor 910 (strictly speaking, the rotor core 911) is provided with a rotation shaft insertion hole 919 into which the rotation shaft 920 is inserted. Further, the rotor 910 is provided with main magnetic pole portions and auxiliary magnetic pole portions alternately in the circumferential direction. Magnet insertion holes 911a to 911d for inserting permanent magnets 912a to 912d are provided in the main magnetic pole portion. In addition, permanent magnets having different polarities are inserted into the magnet insertion holes 911a to 911d of the adjacent main magnetic pole portions.
The stator 930 includes a stator core (stator core) 931 formed by laminating electromagnetic steel plates. In the stator 930 (strictly speaking, the stator core 931), teeth 932 are formed at locations facing the outer peripheral surface of the rotor 910. A slot 933 is formed by the teeth 932, and a stator coil (not shown) is accommodated in the slot 933. The stator 930 is accommodated in a ring (case) 940.
An air conditioner (air conditioner) is driven by a permanent magnet motor, and includes a compressor that compresses a cooling medium, an outdoor heat exchanger that radiates heat from the cooling medium, an indoor heat exchanger that absorbs heat from indoor air, and the like. The cooling medium is circulated. Here, in order to allow the cooling medium to pass through the permanent magnet motor (motor for driving the compressor), the permanent magnet motor is provided with a cooling medium passage through which the cooling medium flows in the axial direction. Yes. For example, as shown in FIG. 21, a notch 934a is formed along the axial direction on the outer peripheral surface of the stator 930 (stator core 931). The notch 934a and the ring (case) 940 constitute a communication hole 934 that communicates in the axial direction. This communication hole 934 is used as a cooling medium passage. Note that a gap (gap) between the rotor and the stator of the permanent magnet motor is also used as the cooling medium passage.
It is also known that a rotor 910 (rotor core 911) of a permanent magnet motor is provided with a communication hole communicating in the axial direction, and the communication hole is used as a cooling medium passage. (See Patent Document 1)
Japanese Patent Laid-Open No. 2001-161040

In a compressor, for example, a rotary compressor, a lubricating oil that lubricates a mechanical part of the compressor is mixed with a cooling medium in a spray state in a sealed container. Here, when the total cross-sectional area of the cooling medium passage provided in the permanent magnet motor is small, the speed of the cooling medium is increased. When the speed of the cooling medium is low, the spray-like lubricating oil falls by its own weight, but when the speed of the cooling medium is high, the spray-like lubricating oil is discharged from the discharge pipe of the compressor together with the cooling medium. . When the sprayed lubricating oil is discharged from the discharge pipe of the compressor, the heat exchange efficiency in the heat exchanger is lowered. Therefore, it is preferable that the total cross-sectional area of the coolant passage (communication hole) provided in the permanent magnet motor used as the compressor driving motor is large.
On the other hand, when the total cross-sectional area of the cooling medium passage (communication hole) provided in the stator is increased, the magnetic flux passage of the stator is narrowed and the magnetic flux density of the stator is increased. When the magnetic flux density of the stator increases, the iron loss of the stator increases and the efficiency of the permanent magnet motor decreases.
Therefore, it is desired to develop a technology for increasing the total cross-sectional area of the cooling medium passage (communication hole) provided in the permanent magnet motor while suppressing the increase in the total cross-sectional area of the cooling medium passage (communication hole) provided in the stator. Has been.
Here, as a method of increasing the total cross-sectional area of the communication hole provided in the permanent magnet motor while suppressing the total cross-sectional area of the communication hole provided in the stator, the communication hole is provided in the rotor described in Patent Document 1. It is conceivable to use technology.
However, as a result of studies by the present inventors, it has been found that when the communication hole is provided in the rotor, the efficiency of the permanent magnet motor varies greatly depending on the position of the communication hole.
An object of this invention is to provide the technique which can provide a communicating hole in a rotor, suppressing the efficiency fall of a permanent magnet motor.

A first invention of the present invention for solving the above problem is a permanent magnet electric motor as set forth in claim 1.
The permanent magnet motor of the present invention drives an electric motor (compressor drive motor) that drives a compressor (compressor) such as an air conditioner (air conditioner) or a refrigerator, an electric motor that drives a vehicle, and an in-vehicle device mounted on the vehicle. It can be used for various applications such as electric motors.
The permanent magnet motor of the present invention includes a stator and a rotor. The stator is typically composed of a stator core formed by stacking electromagnetic steel plates. The stator is provided with teeth at positions facing the outer peripheral surface of the rotor. The teeth are typically configured by a teeth base and teeth ends provided on both sides in the circumferential direction of the teeth base, and a teeth tip surface is formed by the teeth base and the end surfaces of the teeth end on the tip side. A slot is formed by the teeth, and a stator winding is accommodated in the slot.
The rotor is typically composed of a rotor core formed by stacking laminated steel plates. The rotor is provided with a rotation shaft insertion hole. Further, the main magnetic pole portion and the auxiliary magnetic pole portion are alternately arranged in the circumferential direction on the rotor as viewed in a cross section perpendicular to the axial direction. A magnet insertion hole is provided in the main magnetic pole portion, and a permanent magnet is inserted into the magnet insertion hole so that the polarity is different between adjacent main magnetic pole portions. Thereby, both the magnet torque by the magnetic flux of a permanent magnet and the reluctance torque by the saliency of an auxiliary | assistant magnetic pole part can be utilized.
The magnet insertion hole has an inner wall disposed on the rotation shaft insertion hole side, an outer wall disposed on the opposite side of the rotation shaft insertion hole with respect to the inner wall, and a rotor It is comprised by the end wall arrange | positioned in the position facing an outer peripheral surface. Typically, the inner wall and the outer wall are formed in parallel (including substantially parallel), and the end wall is formed in parallel (including substantially parallel) with the outer peripheral surface of the rotor. Depending on the shape of the magnet insertion hole, an inner side wall or an outer side wall is provided.
Further, the rotor is provided with a communication hole communicating in the axial direction. The communication hole of the rotor is typically configured by a hole formed in the rotor core that forms the rotor. In the present invention, the communication hole is parallel to the line along the inner wall of the magnet insertion hole, and the first boundary line and the line along the inner wall that are separated from the line along the inner wall by the tooth width toward the rotary shaft insertion port side. Extends from the point intersecting the d-axis of the main magnetic pole part and the line along the inner wall to the adjacent main magnetic pole part and inserted into the rotor saturation magnetic flux density and the magnet insertion hole It is set so as not to be provided in the second region formed by the second boundary line and the line along the inner wall having an inclination with respect to the magnetic flux density of the magnetic flux flowing from the permanent magnet to the rotor. The configuration in which “the communication hole is not provided in the first region and the second region” means a configuration in which the communication hole is not provided in any of the first region and the second region. The first area formed by the first boundary line and the line along the inner wall is preferably set so as not to include the area on the first boundary line. Further, it is preferable to set the second region formed by the second boundary line and the line along the inner wall so as not to include the region on the second boundary line.
The first boundary line and the line along the inner wall form the first region, the second boundary line and the line along the inner wall form the second region, the first boundary line and A mode in which the first region is formed by a line along the inner wall and another line (for example, an inner side line), a second boundary line, a line along the inner wall, and a further line (for example, the inner side wall) And an embodiment in which two regions are formed.
In general, when designing a permanent magnet motor, the magnetic flux density (design magnetic flux density) of the magnetic flux flowing from the permanent magnet inserted into the magnet insertion hole to the rotor (rotor core) is the magnetic flux of the permanent magnet. It is designed to be smaller than the density (set magnetic flux density).
Here, in a cross section perpendicular to the axial direction of the rotor, a line connecting the center of the rotor and the central portion in the circumferential direction of the main magnetic pole portion is referred to as “d-axis”.
The line along the inner wall of the magnet insertion hole means a line along the inner wall of one magnet insertion hole when the main magnetic pole part is provided with one magnet insertion hole. Means a line connecting lines along the inner wall of each magnet insertion hole, and the outer surface of the rotor from the rotation shaft insertion hole to the main magnetic pole portion. When a plurality of magnet insertion holes are provided in the direction, the line along the inner wall of the magnet insertion hole provided on the rotating shaft insertion hole side is meant. The inclination of the second boundary line is determined by the ratio of the saturation magnetic flux density of the rotor and the magnetic flux density of the magnetic flux flowing from the permanent magnet inserted into the magnet insertion hole to the rotor. It depends on the materials that make up the magnet.
By not providing the communication hole in the first region formed by the first boundary line and the line along the inner wall, a magnetic flux passage through which the q-axis magnetic flux flows can be secured. Thereby, a communication hole can be provided in a rotor, suppressing the fall of reluctance torque (suppressing the efficiency fall of a permanent magnet motor). Further, by not providing the communication hole in the second region formed by the second boundary line and the line along the inner wall, it is possible to secure a magnetic flux passage through which the d-axis magnetic flux flows. Accordingly, the communication hole can be provided in the rotor while suppressing a decrease in magnet torque (while suppressing a decrease in efficiency of the permanent magnet motor). In the present invention, it is possible to obtain an effect of suppressing the decrease in efficiency by securing the magnetic flux path for flowing the q-axis magnetic flux and the effect of suppressing the efficiency decrease by securing the magnetic flux path for allowing the d-axis magnetic flux to flow.
Generally, when a rotor is constituted by a rotor core formed by laminating electromagnetic steel plates, a caulking pin insertion hole for inserting a caulking pin for fixing the rotor core integrally is provided. The position of the caulking pin insertion hole is selected depending on the shape of the magnet insertion hole. The “rotor communication hole” of the present invention does not include a caulking pin insertion hole for inserting the caulking pin. The “rotor communication hole” of the present invention typically has a cooling medium passage for flowing a cooling medium supplied to the heat exchanger, a cooling passage for flowing a cooling medium (for example, cooling air) for cooling the rotor, Used as a hole to reduce the weight of the rotor. When the caulking pin insertion hole is provided in the first region or the second region, it is possible to prevent the effect of the present invention from being reduced by using, for example, a caulking pin made of a magnetic material.
When the permanent magnet motor of the present invention is used as a compressor driving motor that forms a cooling medium passage by the communication hole provided in the stator and the communication hole provided in the rotor, the communication hole provided in the stator A configuration in which the total cross-sectional area is reduced and a configuration in which communication holes are provided in the rotor while suppressing a decrease in efficiency can be combined. Thereby, the efficiency of the whole permanent magnet motor can be improved while ensuring the total cross-sectional area of the cooling medium passage.

A second invention of the present invention is a permanent magnet motor as set forth in claim 2.
In the present invention, the communication hole of the rotor is parallel to the line along the inner wall of the magnet insertion hole, and the first boundary line and the inner wall separated from the line along the inner wall by the tooth width toward the rotation shaft insertion port side. A first region formed by a line along the line, or a line extending along the inner wall and a point intersecting the d-axis of the main magnetic pole part in the direction of the adjacent main magnetic pole part, and the saturation magnetic flux density of the rotor and the magnet It is not provided in one of the second regions formed by the second boundary line and the line along the inner wall that are inclined with respect to the ratio of the magnetic flux density of the magnetic flux flowing from the permanent magnet inserted into the insertion hole to the rotor. .
As the communication hole of the present invention, a communication hole having the same configuration as the communication hole of the first invention can be used.
As described above, since the communication hole is not provided in the first region formed by the first boundary line and the line along the inner wall, it is possible to secure a magnetic flux passage through which the q-axis magnetic flux flows, A decrease in efficiency of the permanent magnet motor can be suppressed. In addition, since the communication hole is not provided in the second region formed by the second boundary line and the line along the inner wall, a magnetic flux passage through which the d-axis magnetic flux flows can be secured, and the permanent magnet motor The efficiency drop can be suppressed.
In the present invention, it is possible to obtain an effect of suppressing the decrease in efficiency by securing the magnetic flux passage for flowing the q-axis magnetic flux or the effect of suppressing the efficiency decrease by securing the magnetic flux passage for flowing the d-axis magnetic flux.

A third invention of the present invention is a permanent magnet motor as set forth in claim 3.
In the present invention, the outer peripheral surface of the rotor intersects the d-axis of the main magnetic pole portion, intersects the first curved surface formed in a protruding shape in the outer peripheral direction, and the q-axis of the auxiliary magnetic pole portion, and the outer peripheral direction. The second curved surfaces formed in a protruding shape are alternately connected. The curvature of the second curved surface is set larger than the curvature of the first curved surface.
Here, in a cross section perpendicular to the axial direction of the rotor, a line connecting the center of the rotor and the central portion in the circumferential direction of the auxiliary magnetic pole portion is referred to as “q-axis”.
The shape of the 1st and 2nd curve surface should just be the curve shape currently formed in the protruding shape in the outer peripheral direction. The circumferential lengths of the first and second curved surfaces (angle with respect to the center of the rotor) are set as appropriate.
According to the present invention, it is possible to prevent the magnetic flux from concentrating on a specific portion of the rotor, and to reduce the change in the amount of magnetic flux to reduce the harmonic component contained in the electromotive force waveform, thereby sufficiently improving the efficiency. Can be improved.

A fourth invention of the present invention is a permanent magnet motor as set forth in claim 4.
In the present invention, the magnet insertion hole has an end wall disposed to face the outer peripheral surface of the rotor. And the notch part is formed in the location which opposes an end wall of the outer peripheral surface of a rotor. Alternatively, a hole is provided between the outer peripheral surface of the rotor and the end wall of the magnet insertion hole. The holes may be voids or may be filled with a nonmagnetic material.
In this invention, it can prevent that the permanent magnet currently inserted in the magnet insertion hole is short-circuited.

A fifth aspect of the present invention is a permanent magnet motor as set forth in the fifth aspect.
In the present invention, the main magnetic pole portion is provided with a plurality of layers of magnet insertion holes in the direction from the rotation shaft insertion hole to the outer peripheral surface of the rotor. And the 1st and 2nd boundary line is set based on the inner wall of the magnet insertion hole provided in the rotating shaft insertion hole side among the multilayer magnet insertion holes.
In the present invention, even for a permanent magnet motor having a rotor in which a plurality of layers of magnet insertion holes are provided in the main magnetic pole portion, the communication holes can be provided in the rotor while suppressing a decrease in efficiency.

A sixth aspect of the present invention is a permanent magnet motor as set forth in the sixth aspect.
In the present invention, the rotor is made of an electromagnetic steel plate, and a neodymium magnet is used as a permanent magnet. The slope of the second boundary line is set to 0.5 (including substantially 0.5).
By using a neodymium magnet as the permanent magnet, a highly efficient permanent magnet motor can be obtained. Generally, the saturation magnetic flux density of the electrical steel sheet is about 1.8 Tesla, and the magnetic flux density (design magnetic flux density) of the magnetic flux flowing from the neodymium magnet to the rotor is designed to be about 0.9 Tesla. In this case, about 0.5 is set as the inclination of the second boundary line.
In the present invention, a rotor (rotor core) is configured by laminating electromagnetic steel plates, and a rotor is provided with a communication hole while suppressing a decrease in efficiency even for a permanent magnet motor using a neodymium magnet as a permanent magnet. be able to.

If the permanent magnet motor of Claims 1-5 is used, the permanent magnet motor which can provide a communicating hole in a rotor can be obtained, suppressing a reduction in efficiency.
When the permanent magnet motor of the present invention is configured as a permanent magnet motor by providing communication holes in the stator and rotor, a configuration that reduces the total cross-sectional area of the communication holes provided in the stator and suppresses a decrease in efficiency. However, the structure which provides a communicating hole in a rotor can be combined. In this case, the efficiency of the entire permanent magnet motor can be improved while ensuring the total cross-sectional area of the communication hole.

  Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, a permanent magnet motor used as a compressor driving motor will be described. Also, a rotor having 4 magnetic poles (2 pole pairs) and a permanent magnet motor in which stator windings are housed in slots in a distributed winding manner will be described.

(First embodiment)
A first embodiment of the present invention is shown in FIGS. 1 is a cross-sectional view perpendicular to the axial direction of the first embodiment, and FIG. 2 is a detailed explanatory view of the embodiment of FIG.
In the present embodiment, a rotor (rotor) 10 and a stator (stator) 30 are provided.
In the present embodiment, the rotor 10 is constituted by a rotor core (rotor core) 11 formed by laminating electromagnetic steel plates.
The rotor 10 (strictly, the rotor core 11) is provided with a rotation shaft insertion hole 19 at the center of rotation. Typically, the rotary shaft 20 having an outer diameter larger than the inner diameter of the rotary shaft insertion hole 19 (having “tightening allowance”) is inserted into the rotary shaft insertion hole 19 by a shrink fitting method or a press-fitting method. The “shrink fitting method” is a method of inserting the rotating shaft 20 into the rotating shaft insertion hole 19 after increasing the inner diameter of the rotating shaft insertion hole 19 by heating the rotor 10. The “press-in method” is a method of inserting the rotary shaft 20 into the rotary shaft insertion hole 19 by pushing the rotary shaft 20 with a strong force.
The rotor 10 has main magnetic pole portions a, b, c, d provided with magnet insertion holes 11a, 11b, 11c, 11d, and auxiliary magnetic pole portions ab, as viewed in a cross section perpendicular to the axial direction. bc, cd, da are alternately arranged in the circumferential direction. Permanent magnets 12a to 12d are inserted into the magnet insertion holes 11a to 11d. The permanent magnets 12a to 12d are typically inserted into the magnet insertion holes using a gap fitting method. That is, when the permanent magnets 12a to 12d are inserted into the magnet insertion holes 11a to 11d, the magnets are inserted so that a gap is formed between the permanent magnets 12a to 12d and the walls that form the magnet insertion holes 11a to 11d. The inner peripheral shape (distance between walls) of the holes 11a to 11d or the outer peripheral shape (length or width of a cross section perpendicular to the axial direction) of the permanent magnets 12a to 12d is set. Further, the polarities of the permanent magnets 12a to 12d inserted into the magnet insertion holes 11a to 11d are selected so that the adjacent main magnetic pole portions a to d have different polarities.
In the present embodiment, the permanent magnets 12a to 12d are inserted into the magnet insertion holes 12a to 12d so that the centers of the permanent magnets 12a to 12d substantially coincide with the centers (d-axis) of the magnet insertion holes 11a to 11d.
As the permanent magnet, a ferrite magnet or a rare earth magnet can be used. Ferrite magnets have the property that the magnetic flux density decreases as the temperature increases. On the other hand, rare earth magnets have a characteristic that the decrease in magnetic flux density is small even when the temperature increases. Here, since the temperature inside the compressor becomes high, when the permanent magnet motor is used as a compressor driving motor, it is preferable to use a rare earth magnet as the permanent magnet. In particular, a rare earth neodymium magnet is preferably used. The neodymium magnet is composed of Nd (neodymium), Fe (iron), Co (cobalt), and B (boron), for example.
As a result, the permanent magnet motor of the present embodiment has the magnet torque generated by the magnetic fluxes of the permanent magnets 12a to 12d inserted in the magnet insertion holes 11a to 11d of the main magnetic pole portions a to d and the auxiliary magnetic pole portions ab to da. Both reluctance torque due to saliency can be used.
In general, caulking pin insertion holes are formed in the electromagnetic steel sheet. And after laminating | stacking an electromagnetic steel plate and forming a laminated body, a laminated body is fixed integrally by inserting a caulking pin in a caulking pin insertion hole. In the present embodiment, the caulking pin is made of a magnetic material. Thereby, even when the caulking pin insertion hole is provided in the first region or the second region described later, it is possible to prevent the magnetic flux path from being reduced by the caulking pin insertion hole. The communication hole of the present invention does not include this caulking pin insertion hole.

In the present embodiment, the main magnetic pole portions a to d are provided with one layer of magnet insertion holes 11a to 11d having a linear cross section perpendicular to the axial direction, and the magnet insertion holes 11a to 11d are provided with an axial direction. A permanent magnet having a rectangular cross-sectional shape (flat plate shape) is inserted.
Since the main magnetic pole portions a to d and the auxiliary magnetic pole portions ab to da provided with the magnet insertion holes 11a to 11d have the same configuration, they are provided on both sides in the circumferential direction of the main magnetic pole portion a and the main magnetic pole portion a. The configuration of the auxiliary magnetic pole portions da and ab will be described. In addition, the code | symbol which attached | subjected "a"-"d" which shows that it is a component of each main magnetic pole part ad is used as a code | symbol of each main magnetic pole part ad.
The magnet insertion hole 11a provided in the main magnetic pole part a is formed by an outer wall 11a1, an inner wall 11a2, end walls 11a3 and 11a4, and inner side walls 11a5 and 11a6.
The inner wall 11a2 is disposed on the rotary shaft insertion hole 19 (rotation center O of the rotor 10) side. The outer wall 11a1 is disposed on the opposite side of the rotation shaft insertion hole 19 with respect to the inner wall 11a2. In the present embodiment, the inner wall 11a2 and the outer wall 11a1 are formed to be orthogonal to and parallel to the d-axis of the main magnetic pole part a. Note that the inner wall 11a2 and the outer wall 11a1 do not have to be strictly orthogonal to the d-axis (may be substantially perpendicular), and may not be strictly parallel (may be substantially parallel).
The end walls 11 a 3 and 11 a 4 are arranged at positions facing the outer peripheral surface of the rotor 10. In the present embodiment, the end walls 11 a 3 and 11 a 4 are formed in parallel to the outer peripheral surface of the rotor 10. Of course, the end walls 11a3 and 11a4 may not be strictly parallel to the outer peripheral surface of the rotor 10 (may be substantially parallel).
In each embodiment described below, unless otherwise specified, the outer wall and inner wall of the magnet insertion hole are formed in parallel (including substantially parallel), and the end wall is parallel (substantially parallel) to the outer peripheral surface of the rotor. Are formed).
The inner side walls 11a5 and 11a6 are provided at positions facing the adjacent main magnetic pole portions, and form magnetic flux paths in the auxiliary magnetic pole portions.
The magnet insertion hole 11a is formed with positioning projections 11a7 and 11a8 that project inward and position the permanent magnet. Accordingly, when the permanent magnet 12a is inserted into the magnet insertion hole 11a, the movement of the permanent magnet 12a is restricted by the positioning protrusions 11a7 and 11a8. In the present embodiment, when the permanent magnets 12a to 12d are inserted into the magnet insertion holes 11a to 11d, gaps are formed between the end portions of the permanent magnets 12a to 12d and the outer peripheral surface of the rotor 10. The By this gap, the magnetic flux short-circuit amount at the ends of the permanent magnets 12a to 12d can be reduced. Thereby, the amount of effective magnetic flux can be increased and the efficiency is improved. Note that the gap can be filled with a non-magnetic material.
Further, on the outer peripheral surface of the rotor 10, notches 10a1 and 10a2 are provided at locations facing the end walls 11a3 and 11a4 of the magnet insertion hole 11a. That is, it has a depth D and a length T in the circumferential direction from a circular surface having a radius of curvature R centered on the rotation center O of the rotor 10 to a position facing the end walls 11a3 and 11a4 (or the rotation center). Angle to O) Notches 10a1 and 10a2 are provided.
Thereby, the outer peripheral surface of the rotor 10 has outer peripheral surfaces 10A to 10D intersecting with the d axis of the main magnetic pole portions a to d, and outer peripheral surfaces 10AB to 10DA intersecting with the q axis of the auxiliary magnetic pole portions ab to da. Yes. The “d-axis” is a line connecting the rotor center O and the circumferential center of the main magnetic pole portions a to d in a cross section perpendicular to the axial direction of the rotor. The “q-axis” is a line connecting the rotor center O and the circumferential center of the auxiliary magnetic pole portions ab to da in a cross section perpendicular to the axial direction of the rotor. Further, the outer peripheral surfaces 10A to 10D, 10AB to 10DA have an arc shape having a radius of curvature R from the rotor center O.

The stator 30 is composed of a stator core (stator core) 31 formed by laminating electromagnetic steel plates. The stator 30 (stator core 31) is accommodated in a ring (case) 40.
The stator (strictly speaking, the stator core 31) is provided with teeth 32 at locations facing the outer peripheral surface of the rotor 10. The teeth 32 are configured by a teeth base portion 32a and teeth end portions 32b and 32c provided on both sides in the circumferential direction of the teeth base portion 32a (the rotation direction of the rotor 10). A tooth tip surface 32d is formed by the tip surfaces of the teeth base 32a and the teeth ends 32b and 32c. The rotor 10 is disposed such that the gap (gap) between the outer peripheral surfaces 10A to 10D of the rotor 10 and the tooth tip surface 32d of the tooth 32 is g.
A slot 33 is formed by the teeth 32. A stator coil (not shown) is accommodated in the slot 33 by a distributed winding method.
In general, caulking pin insertion holes are formed in the electromagnetic steel sheet. And after laminating | stacking an electromagnetic steel plate and comprising a laminated body, a laminated body is fixed by inserting a caulking pin in a caulking pin insertion hole. In the present embodiment, the caulking pin is made of a magnetic material. Thereby, the reduction | decrease of the magnetic flux path by the caulking pin insertion hole formed in a laminated steel plate can be prevented.

The permanent magnet electric motor is provided with a cooling medium passage for discharging the cooling medium flowing into the suction pipe of the compressor from the discharge pipe of the compressor.
In the present embodiment, as shown in FIG. 1, a notch 34a is formed along the axial direction on the outer peripheral surface of the stator 30 (stator core 31) of the permanent magnet motor. A cooling medium passage 34 communicating in the axial direction is provided by a notch 34 a formed on the outer peripheral surface of the stator 30 and a ring (case) 40 that accommodates the stator 30. The arrangement position and cross-sectional area of the cooling medium passage 34 provided in the stator 30 are appropriately set.
In addition, a hole can be formed in the stator core 31 constituting the stator 30 and used as a cooling medium passage.
A communication hole 18 is formed in the rotor 10 of the permanent magnet motor along the axial direction. The communication hole 18 is used as a cooling medium passage.

The q-axis magnetic flux that generates the reluctance torque flows in the magnetic flux path between the auxiliary magnetic pole portions arranged adjacent to each other with the main magnetic pole portion interposed therebetween. Since the magnetic flux paths through which the q-axis magnetic flux flows between the auxiliary magnetic pole portions arranged adjacent to each other with the main magnetic pole portion interposed therebetween are substantially the same, in the following, the auxiliary arranged adjacent to each other with the main magnetic pole portion a interposed therebetween The magnetic flux path between the magnetic pole part da and the auxiliary magnetic pole part ab will be described.
In FIG. 3, between the auxiliary magnetic pole part da and the auxiliary magnetic pole part ab arranged adjacent to each other with the main magnetic pole part a interposed therebetween, from the teeth 32B, the outer peripheral surface 10AB of the auxiliary magnetic pole part ab, the auxiliary magnetic pole part ab, The q-axis magnetic flux flowing in the direction of the teeth 32A via the magnet insertion hole 11a on the rotary shaft insertion hole 19 side (rotation center O side), the auxiliary magnetic pole da, and the outer peripheral surface 10DA of the auxiliary magnetic pole part da is indicated by an arrow. Yes. Note that the q-axis magnetic flux also flows in the reverse direction.
Here, when the stator coil is accommodated in the slot 33 using the distributed winding method, the teeth width T of the teeth 32 (the narrowest width of the teeth base portion 32a) is the outer peripheral surface 10AB of the auxiliary magnetic pole portion 10ab, the auxiliary magnetic pole. It becomes shorter than the length of the outer peripheral surface 10DA of the part 10da in the circumferential direction. For this reason, the amount of the q-axis magnetic flux is limited by the tooth width T of the tooth 32. Therefore, a magnetic flux path having the teeth width T of the teeth 32 only needs to be secured as a magnetic flux path for flowing the q-axis magnetic flux.
A magnetic flux path formed between the auxiliary magnetic pole part da and the auxiliary magnetic pole part ab and having the tooth width T of the tooth 32 is a first region Ma indicated by a right-downward oblique line in FIG. For simplicity, the first region Ma is parallel to the line sa and the line sa along the inner wall 11a2 arranged on the rotation shaft insertion hole 19 side (rotation center O side) of the magnet insertion hole 11a. Yes, and determined by the first boundary line ma that is separated from the line sa by a distance W (= tooth width T) toward the rotary shaft insertion hole 19.
Similarly, the magnetic flux path formed between the auxiliary magnetic pole part ab and the auxiliary magnetic pole part bc and having the teeth width T is a line along the inner wall 11b2 of the magnet insertion hole 11b arranged on the rotating shaft insertion hole 19 side. This is a first region Mb determined by sb and a first boundary line mb that is parallel to the line sb and is separated from the line sb by a distance W (= tooth width T) toward the rotary shaft insertion hole 19. In addition, the magnetic flux path formed between the auxiliary magnetic pole part bc and the auxiliary magnetic pole part cd and having the teeth width T is a line sc along the inner wall 11c2 arranged on the rotating shaft insertion hole 19 side of the magnet insertion hole 11c. And a first region Mc determined by a first boundary line mc parallel to the line sc and separated from the line sc by a distance W (= tooth width T) toward the rotary shaft insertion hole 19. The magnetic flux path formed between the auxiliary magnetic pole part cd and the auxiliary magnetic pole part da and having the teeth width T is a line sd along the inner wall 11d2 of the magnet insertion hole 11d arranged on the rotating shaft insertion hole 19 side. And a first region Md that is determined by a first boundary line md that is parallel to the line sd and separated from the line sd by the distance W (= tooth width T) toward the rotation shaft insertion hole 19.
Therefore, when the communication hole 18 is provided in the rotor 10, the first boundary lines ma to md determined on the basis of the inner walls 11a2 to 11d2 of the magnet insertion holes 11a to 11d provided in the main magnetic pole portions a to d and By not providing the communication hole 18 in the first regions Ma to Md formed by the lines sa to sd along the inner walls 11a2 to 11d2, for example, the rotation axis insertion hole 19 side from the first boundary lines ma to md. By providing the communication hole 18 in this area, it is possible to suppress a decrease in the amount of the q-axis magnetic flux and to suppress a decrease in the reluctance torque. That is, it is possible to suppress a decrease in efficiency of the permanent magnet motor.
The first areas Ma to Md are preferably set so as not to include the areas on the first boundary lines ma to md.

The d-axis magnetic flux that generates the magnet torque flows in the magnetic flux path between the main magnetic pole portions arranged adjacent to each other with the auxiliary magnetic pole portion interposed therebetween. Since the magnetic flux paths through which the d-axis magnetic flux flows between the main magnetic pole portions arranged adjacent to each other with the auxiliary magnetic pole portion interposed therebetween are substantially the same, hereinafter, the main magnetic pole portions arranged adjacent to each other with the auxiliary magnetic pole portion bc interposed therebetween. A magnetic flux path between the magnetic pole part b and the main magnetic pole part c and a magnetic flux path between the main magnetic pole part c and the main magnetic pole part d arranged adjacent to each other with the auxiliary magnetic pole part cd interposed therebetween will be described.
In FIG. 4, between the main magnetic pole part b and the main magnetic pole part c arranged adjacent to each other with the auxiliary magnetic pole part bc interposed therebetween, from the teeth 32E, 32F, and 32G, the outer peripheral surface 10C of the main magnetic pole part c, the main magnetic pole part c, The magnetic pole part c, the permanent magnet 12c inserted in the magnet insertion hole 11c provided in the main magnetic pole part c, the auxiliary magnetic pole part bc adjacent to the main magnetic pole part c, and the main magnetic pole part b adjacent to the auxiliary magnetic pole part bc The d-axis magnetic flux flowing in the direction of the teeth 32C and 32D via the permanent magnet 12b, the main magnetic pole part b, and the outer peripheral surface 10B of the main magnetic pole part b inserted in the provided magnet insertion hole 11b, and the auxiliary magnetic pole part cd From the teeth 32E, 32F, and 32G to the outer peripheral surface 10C, the main magnetic pole part c, and the main magnetic pole part c of the main magnetic pole part c between the main magnetic pole part c and the main magnetic pole part d arranged adjacent to each other. Permanently inserted in the provided magnet insertion hole 11c Magnet 12c, auxiliary magnetic pole part cd adjacent to main magnetic pole part c, permanent magnet 12d inserted in magnet insertion hole 11d provided in main magnetic pole part d adjacent to auxiliary magnetic pole part cd, main magnetic pole part d, main magnetic pole part d The d-axis magnetic flux flowing in the direction of the teeth 32H and 32I via the outer peripheral surface 10D of the magnetic pole part d is indicated by an arrow. The d-axis magnetic flux is provided in the permanent magnet inserted in the magnet insertion hole provided in the main magnetic pole part and the main magnetic pole part arranged adjacent to both sides in the circumferential direction with respect to the main magnetic pole part. (In FIG. 4, the magnetic flux flowing from the permanent magnet 12c is divided into two in the direction of the permanent magnets 12b and 12d). The d-axis magnetic flux also flows in the reverse direction.
Here, generally, the maximum value of the magnetic flux density specific to the electromagnetic steel sheet is smaller than the maximum value of the magnetic flux density of the permanent magnet. For this reason, the maximum value of the amount of magnetic flux flowing between the permanent magnets provided in the adjacent main magnetic pole portions is limited by the maximum value of the amount of magnetic flux flowing from the permanent magnet to the rotor. Further, the maximum value of the amount of magnetic flux flowing through a rotor (rotor core) formed by laminating electromagnetic steel sheets is determined based on the saturation magnetic flux density of the electromagnetic steel sheets. The maximum value of the amount of magnetic flux flowing from the permanent magnet to the rotor (rotor core) is designed based on the magnetic flux density (set magnetic flux density) of the permanent magnet.
For this reason, the magnetic flux path for flowing the d-axis magnetic flux is determined by the saturation magnetic flux density of the rotor 10 (rotor core 11) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 12c to the rotor 10 (rotor core 11). What is necessary is just to ensure the magnetic flux path.
It is formed between the main magnetic pole part c and the main magnetic pole parts b and d, and is determined by the saturation magnetic flux density of the rotor 10 (rotor core 11) and the magnetic flux density flowing from the permanent magnet 12c to the rotor 10 (rotor core 11). The magnetic flux paths are second regions Nc1 and Nc2 indicated by right oblique lines in FIG. In the second regions Nc1 and Nc2, the line sc along the inner wall 11c2 of the magnet insertion hole 11c provided in the main magnetic pole part c, and the line sc and the d axis of the main magnetic pole part c intersect each other. From the point Pc in the direction of the main magnetic pole portions b and d adjacent in the circumferential direction, the length L corresponding to the saturation magnetic flux density of the rotor 10 (rotor core) and the permanent magnet 12c to the rotor 10 (rotor core 11). ) Is determined by the second boundary lines nc1 and nc2 having an inclination of a ratio (H / L) to the length H corresponding to the magnetic flux density of the magnetic flux flowing in the above. The point Pc is preferably the center point of the side surface of the permanent magnet provided on the main magnetic pole part c on the side of the rotary shaft insertion hole 19, but normally the center of the permanent magnet is the center of the main magnetic pole part ( Since the permanent magnet 12c is arranged in the main magnetic pole part c so as to substantially coincide with the (d axis), in this embodiment, the point where the line sc intersects the d axis is used as the point Pc.
Similarly, the magnetic flux path formed between the main magnetic pole part a and the main magnetic pole parts b and d includes a line sa and a line sa along the inner wall 11a2 of the magnet insertion hole 11a provided in the main magnetic pole part a. The saturation magnetic flux density of the rotor 10 and the magnetic flux density of the magnetic flux flowing from the permanent magnet 12a to the rotor 10 extend in the direction of the main magnetic pole parts b and d adjacent in the circumferential direction from the point where the d-axis of the main magnetic pole part a intersects. The second regions Na1 and Na2 are determined by the second boundary lines na1 and na2 having a slope equal to the ratio (H / L). In addition, the magnetic flux path formed between the main magnetic pole part b and the main magnetic pole parts a and c includes the line sb along the inner wall 11b2 of the magnet insertion hole 11b provided in the main magnetic pole part b, the line sb, and the main magnetic path part. A point extending from the point where the d-axis of the magnetic pole part b intersects in the direction of the main magnetic pole parts a and c adjacent to each other in the circumferential direction. The second regions Nb1 and Nb2 are determined by the second boundary lines nb1 and nb2 having a slope equal to the ratio (H / L). The magnetic flux path formed between the main magnetic pole part d and the main magnetic pole parts c and a includes a line sd along the inner wall 11d of the magnet insertion hole 11d provided in the main magnetic pole part d, the line sd, and the main magnetic path part d. A point extending from the point where the d-axis of the magnetic pole part d intersects in the direction of the main magnetic pole part c, a that is adjacent in the circumferential direction, The second regions Nd1 and Nd2 are determined by the second boundary lines nd1 and nd2 having an inclination equal to the ratio (H / L).
Therefore, when the communication hole 18 is provided in the rotor 10, the second boundary lines na1 and na2 determined based on the inner walls 11a2 to 11d2 of the magnet insertion holes 11a to 11d provided in the main magnetic pole portions a to d. By not providing the communication holes 18 in the second regions Na1, Na2 to Nd1, and Nd2 formed by the lines sa to sd along the inner walls 11a2 to 11d2 and in other words, the second boundary line na1, By providing the communication hole 18 in a region closer to the rotary shaft insertion hole 19 than na2 to nd1 and nd2, a decrease in the amount of d-axis magnetic flux can be suppressed, and a decrease in magnet torque can be suppressed. That is, it is possible to suppress a decrease in efficiency of the permanent magnet motor.
The second regions Na1, Na2 to Nd1, and Nd2 are preferably set so as not to include the regions on the second boundary lines na1, na2 to nd1, and nd2.

As the permanent magnet of the permanent magnet motor, various magnets such as ferrite magnets and rare earth magnets can be used. Rare earth magnets are used. Among rare earth magnets, neodymium magnets are used from the viewpoint of improving the efficiency of permanent magnet motors. Generally, the magnetic flux density (set magnetic flux density) of a neodymium magnet is set in the range of about 1.1 Tesla to 1.4 Tesla.
Here, when the permanent magnet motor is manufactured, the magnetic flux density of the magnetic flux flowing from the permanent magnet to the rotor (rotor core) is designed to be lower than the set magnetic flux density. For example, it is designed such that a magnetic flux having a magnetic flux density (design magnetic flux density) of about 0.9 Tesla flows from a permanent magnet to the rotor 10 (rotor core 11).
The saturation magnetic flux density of the electrical steel sheet constituting the rotor is generally about 1.8 Tesla.
In this case, the ratio (H / L) between the length L corresponding to the saturation magnetic flux density of the rotor 10 and the length H corresponding to the magnetic flux density of the magnetic flux flowing from the permanent magnet to the rotor (rotor core) described above. Becomes (H / L = 0.9 / 1.8 = 1/2). That is, the lines sa to sd along the inner walls 11a2 to 11d2 of the magnet insertion holes 11a to 11d provided in the main magnetic pole parts a to d intersect with the lines sa to sd and the d axes of the main magnetic pole parts a to d. The second regions Na1, Na2 to Nd1 determined by the second boundary lines na1, na2 to nd1, and nd2 extending from the point in the direction of the main magnetic pole portion adjacent to both sides in the circumferential direction and having an inclination of approximately 0.5. , Nd2 is formed.

The communication hole 18 is formed by the region X of the rotor 10 shown in FIG. 5, that is, the first boundary lines ma to md and the lines sa to sd along the inner walls 11a2 to 11d2 of the magnet insertion holes 11a to 11d. First regions Ma to Md (see FIG. 3), second boundary lines na1, na2 to nd1, and nd2 and lines sa to sd along the inner walls 11a2 to 11d2 of the magnet insertion holes 11a to 11d. In the case where the second regions Na1, Na2 to Nd1, and Nd2 (see FIG. 4) are not provided, for example, the second boundary line is a region closer to the rotation shaft insertion hole 19 than the first boundary lines ma to md. FIG. 6 shows the results of studying the efficiency of the permanent magnet motor when it is provided in the region Y closer to the rotary shaft insertion hole 19 than na1, na2 to nd1, and nd2. In FIG. 6, the horizontal axis represents the total cross-sectional area of the communication hole, and the vertical axis represents the efficiency of the permanent magnet motor. FIG. 6 shows a graph of “total area of communication holes—efficiency” when using the same size stator and rotor and changing the arrangement position, number, and cross-sectional area of the communication holes.
As shown in FIG. 6, when the communication hole 18 is provided in the region Y without providing the communication hole 18 in the region X, the efficiency of the permanent magnet motor is increased even if the total cross-sectional area of the communication hole 18 is increased. Has hardly decreased. On the other hand, when the communication hole 18 is provided in the region X, the efficiency of the permanent magnet motor decreases as the total cross-sectional area of the communication hole 18 increases.
Accordingly, the first regions Ma to Md (see FIG. 3) and the second region Na1 determined based on the inner walls 11a2 to 11d2 of the magnet housing holes 11a to 11d of the main magnetic pole portions a to d shown in FIG. In a state where the region X including Na2 to Nd1 and Nd2 (see FIG. 4) is secured, the region excluding the region X, for example, the region closer to the rotary shaft insertion hole 19 than the first boundary lines ma to md By providing the communication hole 18 in the region Y closer to the rotation shaft insertion hole 19 than the second boundary lines na1, na2 to nd1, and nd2, the communication hole 18 is formed in the rotor 10 without reducing the efficiency of the permanent magnet motor. Can be provided.

As described above, in order to prevent the heat exchange efficiency in the heat exchanger from being lowered due to the discharge of the spray-like lubricating oil, it is necessary to increase the total cross-sectional area of the communication holes used as the cooling medium passage. The communication hole used as the cooling medium passage may be provided in either the stator or the rotor of the permanent magnet motor.
In the present embodiment, the communication hole 34 is provided in the stator 30 and the communication hole 18 is provided in the rotor 10.
Accordingly, when securing the total cross-sectional area of the communication holes necessary to prevent the heat exchange efficiency in the heat exchanger from being lowered due to the discharge of the spray-like lubricating oil, the communication holes 34 provided in the stator 30 The total cross-sectional area can be reduced.
In the present embodiment, the region Y excluding the region X determined by the teeth width, the saturation magnetic flux density of the rotor, and the magnetic flux density (design magnetic flux density) of the permanent magnet, that is, the inner wall 11a2 of the magnet insertion holes 11a to 11d. A communication hole 18 is provided in a region Y closer to the rotary shaft insertion hole 19 than the first boundary lines ma to md and the second boundary lines na1, na2 to nd1, and nd2 set on the rotary shaft insertion hole 19 side from ˜11d2. ing. Accordingly, the communication hole 18 can be provided in the rotor 10 without reducing the efficiency of the permanent magnet motor.
Thus, in this Embodiment, the structure which reduces the total cross-sectional area of the communicating hole 34 provided in a stator and improves the efficiency of a permanent magnet motor, 1st boundary line ma-md, and 2nd boundary line A configuration in which the communication hole 18 is not provided in the region X determined by na1, na2 to nd1, and nd2 (a configuration in which the communication hole 18 is provided in the region Y), that is, in the rotor 10 without reducing the efficiency of the permanent magnet motor. A configuration in which the communication hole 18 can be provided can be used in combination. Thereby, the efficiency of a permanent magnet electric motor can be improved.

Further, when the rotary shaft 20 is inserted into the rotary shaft insertion hole 19, a stress that increases the outer diameter of the rotor 10 is applied to the permanent magnets 12a to 12d. In particular, when the rotary shaft 20 is inserted into the rotary shaft insertion hole 19 using the shrink fitting method, the stress due to the difference between the thermal expansion coefficient of the rotor 10 (rotor core 11) and the thermal expansion coefficients of the permanent magnets 12a to 12d. Are also added to the permanent magnets 12a to 12d. For this reason, when inserting the rotating shaft 20 in the rotating shaft insertion hole 19, there exists a possibility that the permanent magnets 12a-12d may be cracked or chipped.
In the present embodiment, a communication hole 18 is provided between the magnet insertion holes 11 a to 11 d and the rotary shaft insertion hole 19. Thereby, the stress that increases the outer diameter of the rotor 10 is absorbed by the communication hole 18. In addition, when the rotary shaft 20 is inserted into the rotary shaft insertion hole 19 using the shrink-fitting method, the communication hole 18 suppresses heat transfer to the permanent magnets 12a to 12d. Thereby, the crack and the chip | tip by the stress of permanent magnet 12a-12d can be prevented.

In the above description, the first regions Ma to Md corresponding to the magnet insertion holes 11a to 11d are simply formed by the first boundary lines ma to md and the lines sa to sd along the inner walls 11a2 to 11d2. The second regions Na1, Na2 to Nd1, and Nd2 corresponding to the magnet insertion holes 11a to 11d are formed by the second boundary lines na1, na2 to nd1, and nd2 and the lines sa to sd along the inner walls 11a2 to 11d2. However, the first regions Ma to Md and the second regions Na1, Na2 to Nd1, and Nd2 can be formed more accurately. For example, as shown in FIG. 3, the first region Ma corresponding to the magnet insertion hole 11a is divided into a first boundary line ma, a line sa along the inner wall 11a2, and a line sa2 along the inner side walls 11a5 and 11a6. , Sa3, and as shown in FIG. 4, second regions Nc1 and Nc2 corresponding to the magnet insertion holes 11c are divided into second boundary lines nc1 and nc2, and a line sc along the inner wall 11c2. It can also be formed by lines sc2 and sc3 along the inner side walls 11c5 and 11c6 (regions indicated by slanting right-down lines in FIGS. 3 and 4). In this case, it is possible to set the first region and the second region that can more effectively suppress the decrease in efficiency. In this case, the first regions Mb to Md and the second regions Nb1, Nb2 to Nd1, and Nd2 corresponding to the magnet insertion holes 11b to 11d are set similarly.
Moreover, as an aspect which does not provide the communication hole 18 in 1st area | region Ma-Md and 2nd area | region Na1, Na2-Nd1, Nd2, in the area | region of the rotating shaft insertion hole 19 side from 1st boundary line ma-md. In addition, a mode in which a communication hole is provided in the region Y closer to the rotary shaft insertion hole 19 than the second boundary lines na1, na2 to nd1, and nd2, and the outer periphery of the rotor 10 from the outer walls 11a1 to 11d1 of the magnet insertion holes 11a to 11d The aspect which provides a communicating hole in the area | region of a surface side is contained. From the viewpoint of securing the area of the passage through which the magnetic flux for generating the magnet torque flows, the second boundary lines na1 and na2 are areas on the rotating shaft insertion hole 19 side from the first boundary lines ma to md. It is preferable to use a mode in which a communication hole is provided in the region Y closer to the rotary shaft insertion hole 19 than nd1 and nd2.
Such a configuration can also be used in the following embodiments.

In the first embodiment, a permanent magnet having a rectangular cross-sectional shape is inserted into a single layer magnet insertion hole having a linear cross-sectional shape. However, the shape and number of the magnet insertion holes and permanent magnets are appropriately determined. It can be changed. Other embodiments will be described below.
In the following description, a stator similar to the stator shown in FIGS. 1 and 2 is used as the stator, and thus description thereof is omitted. Moreover, although the positioning protrusion for positioning a permanent magnet in a magnet insertion hole is abbreviate | omitted and demonstrated, a positioning protrusion can also be provided.
(Second Embodiment)
A second embodiment is shown in FIGS. In the second embodiment, a plurality of permanent magnets having a rectangular cross section perpendicular to the axial direction are inserted into a single layer magnet insertion hole having a trapezoidal cross section perpendicular to the axial direction. .
In the present embodiment, the rotor 110 has a trapezoidal shape in which each of the main magnetic pole portions a to d has a cross-sectional shape perpendicular to the axial direction that is concave in the outer circumferential direction (projecting in the central direction). One layer of magnet insertion holes 111a to 111d is provided.
The magnet insertion hole 111a includes an outer wall 111a1, an inner wall 111a2, outer side walls 111a3 and 111a4, inner side walls 111a5 and 111a6, and end walls 111a7 and 111a8. In addition, permanent magnets 112a1, 112a2, and 112a3 having a rectangular cross section are inserted into the magnet insertion hole 111a. The other magnet insertion holes 111b to 111d have the same configuration as the magnet insertion hole 111a.
Similarly to the first embodiment, notches 110 a 1, 110 a 2 to 110 d 1, and 110 d 2 are formed on the outer peripheral surface of the rotor 110 at locations facing the end walls of the magnet insertion holes 111 a to 111 d. . Thereby, the outer peripheral surface of the rotor 110 (rotor core 111) is constituted by outer peripheral surfaces 110A to 110D corresponding to the main magnetic pole portions a to d and outer peripheral surfaces 110AB to 110DA corresponding to the auxiliary magnetic pole portions ab to da. Yes.

In the present embodiment, as shown in FIG. 8, the inner wall 111a2 of the magnet insertion hole 111a is parallel to the line sa along the inner wall 111a2, and the distance from the line sa to the rotation shaft insertion hole 119 side (rotation center O). A first region Ma corresponding to the magnet insertion hole 111a is formed by the first boundary line ma separated by W (= the teeth width T). Although not shown in FIG. 8, the inner walls 111b2 to 111d2 of the magnet insertion holes 111b to 111d and the first boundary lines mb to md (see FIG. 9) similar to the first boundary line ma. First regions Mb to Md corresponding to the magnet insertion holes 111b to 111d are formed.
Further, as shown in FIG. 8, the direction from the inner wall 111c2 of the magnet insertion hole 111c and the point Pc where the line sc along the inner wall 111c2 intersects the d axis of the main magnetic pole part c to the adjacent main magnetic pole parts b and d. The second boundary lines nc1 and nc2 are inclined with a ratio of the saturation magnetic flux density of the rotor 110 (rotor core 111) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 112c1 to the rotor 110 (rotor core 111). As a result, second regions Nc1 and Nc2 corresponding to the magnet insertion holes 111c are formed. Although not shown in FIG. 8, the inner walls 111a2, 111b2, 111d2 of the magnet insertion holes 111a, 111b, 111d and the second boundary lines na1, na2, similar to the second boundary lines nc1, nc2, Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 111a, 111b, and 111d are formed by nb1, nb2, nd1, and nd2 (see FIG. 9).
And 1st area | region Ma-Md formed by area | region X (For example, 1st boundary line ma-md (refer FIG. 9) and line sa-sd along inner wall 111a2-111d2 of magnet insertion hole 111a-111d). (Not shown), and second regions formed by second boundary lines na1, na2-nd1, nd2 (see FIG. 9) and lines sa-sd along inner walls 111a2-111d2 of magnet insertion holes 111a-111d No communication hole is provided in Na1, Na2-Nd1, Nd2), and the region Y (the region closer to the rotation shaft insertion hole 119 than the first boundary lines ma-md is the second boundary line na1, na2-nd1). , A communication hole is provided in a region closer to the rotary shaft insertion hole 119 than nd2 (see FIG. 9).
This embodiment also has the same effect as the first embodiment.

In the above description, the first regions Ma to Md are simply formed by the lines sa to sd along the first boundary lines ma to md and the inner walls 111a2 to 111d2, and the second regions Na1, Na2 to Nad are formed. Nd1 and Nd2 are formed by the second boundary lines na1, na2 to nd1, and nd2 and lines sa to sd along the inner walls 111a2 to 111d2, but the first regions Ma to Md and the second regions Na1, Na2 Nd1 and Nd2 can also be formed more accurately. For example, as shown in FIG. 8, the first region Ma is formed by a first boundary line ma, a line sa along the inner wall 111a2, and lines sa2 and sa3 along the inner side walls 111a5 and 111a6. The second regions Nc1 and Nc2 can be formed by the second boundary lines nc1 and nc2, the line sc along the inner wall 111c2, and the lines sc2 and sc3 along the inner side walls 111c5 and 11c6 (the hatched lines in FIG. 8). Area). In this case, the first regions Mb to Md and the second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 are set similarly.
Thereby, the 1st area | region and 2nd area | region which can suppress an efficiency fall more effectively can be formed.

(Third embodiment)
A third embodiment is shown in FIGS. In the third embodiment, the cross-sectional shape perpendicular to the axial direction is perpendicular to the axial direction in a single-layer magnet insertion hole having a V-shape that is formed in a concave shape (projecting in the central direction) in the outer circumferential direction. A plurality of permanent magnets having a rectangular cross-sectional shape are inserted.
In the present embodiment, in the rotor 210, each main magnetic pole part ad has a V-shaped magnet shape in which a cross-sectional shape perpendicular to the axial direction is formed in a concave shape in the outer peripheral direction. One layer of holes 211a to 211d is provided.
The magnet insertion hole 211a includes outer walls 211a1, 211a2, inner walls 211a3, 211a4, and end walls 211a5, 211a6. In addition, permanent magnets 212a1 and 212a2 having a rectangular cross section are inserted into the magnet insertion hole 211a. The other magnet insertion holes 211b to 211d have the same configuration as the magnet insertion hole 211a.
Similarly to the first embodiment, on the outer peripheral surface of the rotor 210 (rotor core 211), notches 210a1, 210a2 to 210d1, at positions facing the end walls of the magnet insertion holes 211a to 211d, 210d2 is formed. Thereby, the outer peripheral surface of the rotor 210 is configured by outer peripheral surfaces 210A to 210D corresponding to the main magnetic pole portions a to d and outer peripheral surfaces 210AB to 210DA corresponding to the auxiliary magnetic pole portions ab to da.

In the present embodiment, as shown in FIG. 11, the line sa1 along the inner wall 211a3 of the magnet insertion hole 211a is parallel to the line sa1, and the distance from the line sa1 to the rotation shaft insertion hole 219 side (rotation center O). The first boundary line ma1 separated by W (= the teeth width T), the line sa2 along the inner wall 211a4 of the magnet insertion hole 211a, and parallel to the line sa2, and from the line sa2 to the rotation shaft insertion hole 219 First regions Ma1 and Ma2 corresponding to the magnet insertion hole 211a are formed by the first boundary line ma2 that is separated by a distance W (= tooth width T) on the side (rotation center O). Although not shown in FIG. 11, the inner walls 211b3, 211b4 to 211d3, and 211d4 of the magnet insertion holes 211b to 211d and the first boundary lines mb1 and mb2 similar to the first boundary lines ma1 and ma2 are used. First regions Mb1, Mb2 to Md1, and Md2 corresponding to the magnet insertion holes 211b to 211d are formed by md1 and md2 (see FIG. 12).
Further, as shown in FIG. 11, a line sc1 along the inner wall 211c3 of the magnet insertion hole 211c, a line sc2 (a line along the inner wall of the magnet insertion hole) along the inner wall 211c4 of the magnet insertion hole 211c, a line sc1 and From the point Pc where the line sc2 and the d axis of the main magnetic pole part c intersect, it extends in the direction of the adjacent main magnetic pole parts b, d, and from the saturation magnetic flux density of the rotor 210 (rotor core 211) and the permanent magnets 212c1, 212c2. Second regions Nc1 and Nc2 corresponding to the magnet insertion hole 211c are formed by the second boundary lines nc1 and nc2 having an inclination of the ratio of the magnetic flux density of the magnetic flux flowing through the rotor 210 (rotor core 211). Yes. Although not shown in FIG. 11, the inner walls 211a3, 211a4, 211b3, 211b4, 211d3, and 211d4 of the magnet insertion holes 211a, 211b, and 211d and the second boundary lines nc1 and nc2 are the same as the second boundary lines nc1 and nc2. The boundary areas na1, na2, nb1, nb2, nd1, nd2 (see FIG. 12) form second regions Na1, Na2, Nb1, Nb2, Nd1, Nd2 corresponding to the magnet insertion holes 211a, 211b, 211d. ing.
Then, the region X (for example, the first boundary lines ma1, ma2 to md1, and md2 and the first lines formed by the lines sa1, sa2 to sd1, and sd2 along the inner walls 211a3, 211a4 to 211d3, and 211d4 of the magnet insertion hole 211a. Area Ma1, Ma2-Md1, Md2 and second boundary lines na1, na2-nd1, nd2 and lines sa1, sa2-sd1, sd2 along inner walls 211a3, 211a4-211d3, 211d4 of magnet insertion holes 211a-211d. Without being provided in the second region Na1, Na2-Nd1, Nd2) formed by the region Y (the first boundary lines ma1, ma2-md1, md2 are regions closer to the rotation shaft insertion hole 219), The communication holes are provided in the boundary lines na1, na2 to nd1, and nd2 (regions closer to the rotation shaft insertion hole 219) (FIG. 12). Irradiation).
This embodiment also has the same effect as the first embodiment.

(Fourth embodiment)
A fourth embodiment is shown in FIGS. In the fourth embodiment, the cross-sectional shape perpendicular to the axial direction is perpendicular to the axial direction in a single-layer magnet insertion hole having a curved shape formed in a concave shape (projecting shape in the central direction) in the outer circumferential direction. A permanent magnet having a curved cross-sectional shape is inserted.
In the present embodiment, the rotor 310 has a magnet insertion hole 311a having a curved shape in which a cross-sectional shape perpendicular to the axial direction is formed in a concave shape in the outer peripheral direction in each main magnetic pole portion ad. ˜311d is provided in one layer.
The magnet insertion hole 311a includes an outer wall 311a1, an inner wall 311a2, and end walls 311a3 and 311a4. A permanent magnet 312a having a curved cross section is inserted into the magnet insertion hole 311a.
Similarly to the first embodiment, the outer peripheral surface of the rotor 310 (rotor core 311) is provided with notches 310a1, 310a2-310d1, at locations facing the end walls of the magnet insertion holes 311a-311d, 310d2 is formed. Thereby, the outer peripheral surface of the rotor 310 is configured by outer peripheral surfaces 310A to 310D corresponding to the main magnetic pole portions a to d and outer peripheral surfaces 310AB to 310DA corresponding to the auxiliary magnetic pole portions ab to da.

In the present embodiment, the line is parallel to the line sa along the inner wall 311a2 of the magnet insertion hole 311a, and is separated from the line sa by the distance W (= tooth width T) from the rotation axis insertion hole 319 side (rotation center O). Is the first boundary line ma (see FIG. 14).
Further, from the point Pc where the line sc along the inner wall 311c2 of the magnet insertion hole 311c intersects the d axis of the main magnetic pole part c, it extends in the direction of the adjacent main magnetic pole part, and the saturation magnetic flux of the rotor 310 (rotor core). The lines that incline the ratio of the density and the magnetic flux density of the magnetic flux flowing from the permanent magnet 312c to the rotor 310 (rotor core 311) are defined as second boundary lines nc1 and nc2 (see FIG. 14). In the present embodiment, the saturation magnetic flux of the rotor 310 is tangential (the vector direction of the primary differential value) with respect to the tangential direction of the line sc (the vector direction of the primary differential value) along the inner wall 311c2. The second boundary lines nc1 and nc2 are determined so as to have an inclination corresponding to the ratio between the length L corresponding to the density and the length H corresponding to the magnetic flux density of the permanent magnet 312c.
In the present embodiment, as shown in FIG. 14, the line sa along the inner wall 311a2 of the magnet insertion hole 311a is parallel to the line sa, and the distance from the line sa to the rotation shaft insertion hole 319 side (rotation center O). A first region Ma corresponding to the magnet insertion hole 311a is formed by the first boundary line ma separated by W (= the teeth width T). Although not shown in FIG. 14, the inner walls 311b2 to 311d2 of the magnet insertion holes 311b to 311d and the first boundary lines mb to md (see FIG. 15) similar to the first boundary line ma. First regions Mb to Md corresponding to the magnet insertion holes 311b to 311d are formed.
Further, as shown in FIG. 14, from the point Pc where the line sc along the inner wall 311c2 of the magnet insertion hole 311c intersects the d axis of the main magnetic pole part c, it extends in the direction of the adjacent main magnetic pole parts b and d and rotates. The second boundary lines nc1 and nc2 having a gradient between the saturation magnetic flux density of the rotor 310 (rotor core 311) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 312c to the rotor 310 (rotor core 311) Second regions Nc1 and Nc2 corresponding to the insertion hole 311c are formed. In the present embodiment, the saturation magnetic flux of the rotor 310 is tangential (the vector direction of the primary differential value) with respect to the tangential direction of the line sc along the inner wall 311c2 (the vector direction of the primary differential value). The second boundary lines nc1 and nc2 are determined so as to have an inclination corresponding to the ratio between the length L corresponding to the density and the length H corresponding to the magnetic flux density of the permanent magnet 312c. Although not shown in FIG. 14, the inner walls 311a2, 311b2, and 311d2 of the magnet insertion holes 311a, 311b, and 311d and the second boundary lines na1, na2, and the second boundary lines nc1 and nc2, Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 311a, 311b, and 311d are formed by nb1, nb2, nd1, and nd2 (see FIG. 15).
Then, the region X (for example, the first boundaries Ma to Md formed by the lines sa to sd along the inner walls 311a2 to 311d2 of the first boundary lines ma to md and the magnet insertion holes 311a to 311d, and the second The communication holes 18 are provided in the second regions Na1, Na2-Nd1, Nd2) formed by the boundaries sa1, na2-nd1, nd2 and lines sa-sd along the inner walls 311a2-311d2 of the magnet insertion holes 311a-311d. In the region Y (the region closer to the rotation axis insertion hole 319 than the first boundary lines ma to md and the region closer to the rotation axis insertion hole 319 than the second boundary lines na1, na2 to nd1, and nd2). A communication hole is provided (see FIG. 15).
This embodiment also has the same effect as the first embodiment.

In the above embodiment, the case where the radius of curvature of the outer peripheral surface corresponding to the main magnetic pole portion and the outer peripheral surface corresponding to the auxiliary magnetic pole portion are set to the same value has been described. Here, if the radius of curvature of the outer peripheral surface corresponding to the main magnetic pole portion and the outer peripheral surface corresponding to the auxiliary magnetic pole portion are set to the same value, when the boundary portion between the main magnetic pole portion and the auxiliary magnetic pole portion passes the teeth, the teeth There is a risk that the magnetic flux passing through will change abruptly and generate noise or vibration.
In this case, by making the curvature radius of the outer peripheral surface corresponding to the main magnetic pole portion different from the curvature radius of the outer peripheral surface corresponding to the auxiliary magnetic pole portion, when the boundary between the main magnetic pole portion and the auxiliary magnetic pole portion passes the teeth, the teeth It is possible to prevent the magnetic flux passing through a sudden change.
(Fifth embodiment)
A fifth embodiment is shown in FIG. In the fifth embodiment, a permanent magnet having a rectangular cross-sectional shape perpendicular to the axial direction is inserted into a single-layer magnet insertion hole having a linear cross-sectional shape perpendicular to the axial direction.
In the present embodiment, the rotor 410 (rotor core 411) has one magnet insertion hole 411a to 411d having a linear cross section perpendicular to the axial direction in each main magnetic pole part a to d. Layers are provided.
The magnet insertion hole 411a includes an outer wall 411a1, an inner wall 411a2, end walls 411a3 and 411a4, and inner side walls 411a5 and 411a6. A permanent magnet 412a having a rectangular cross section is inserted into the magnet insertion hole 411a.
In the present embodiment, the outer peripheral surface of the rotor 410 intersects the d-axis of the main magnetic pole portions a to d and has a curved shape (arc shape) having a first radius of curvature Rd centered on the center O of the rotor 410. ) And outer circumferential surfaces 410AB to 410DA having a curved shape (circular arc shape) having a second radius of curvature Rq centering on the point Q intersecting with the q axis of the auxiliary magnetic pole portions ab to da. Has been. The center of curvature Q of the outer peripheral surface 410CD is provided on the opposite side to the outer peripheral surface 410CD with respect to the center 0 of the rotor, and the second radius of curvature Rq is set to be larger than the first radius of curvature Rd. (Rq> Rd).

In the present embodiment, as shown in FIG. 16, the line sa along the inner wall 411a2 of the magnet insertion hole 411a is parallel to the line sa, and the distance from the line sa to the rotation shaft insertion hole 419 side (rotation center O). A first region Ma corresponding to the magnet insertion hole 411a is formed by the first boundary line ma separated by W (= the teeth width T). Although not shown in FIG. 16, the inner walls 411b2 to 411d2 of the magnet insertion holes 411b to 411d and the first boundary lines mb to md similar to the first boundary line ma are used to form the magnet insertion holes 411b to 411b. First regions Mb to Md corresponding to 411d are formed.
Further, as shown in FIG. 16, the direction of the adjacent main magnetic pole portions b and d from the line sc along the inner wall 411c2 of the magnet insertion hole 411c and the point Pc where the line sc intersects the d axis of the main magnetic pole portion c. The second boundary lines nc1 and nc2 with a ratio of the saturation magnetic flux density of the rotor 410 (rotor core 411) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 412c to the rotor 410 (rotor core 411) as an inclination. As a result, second regions Nc1 and Nc2 corresponding to the magnet insertion holes 411c are formed. Although not shown in FIG. 16, the inner walls 411a2, 411b2, 411d2 of the magnet insertion holes 411a, 411b, 411d and the second boundary lines na1, na2, the same as the second boundary lines nc1, nc2, Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 411a, 411b, and 411d are formed by nb1, nb2, nd1, and nd2.
Then, the region X (for example, the first boundaries Ma to Md formed by the lines sa to sd along the inner walls 411a2 to 411d2 of the first boundary lines ma to md and the magnet insertion holes 411a to 411d, and the second 2nd region Na1, Na2 to Nd1, Nd2) formed by boundary lines na1, na2 to nd1, nd2 and lines sa to sd along inner walls 411a2 to 411d2 of magnet insertion holes 411a to 411d A communication hole is provided in Y (a region closer to the rotation shaft insertion hole 419 than the first boundary lines ma to md and a region closer to the rotation shaft insertion hole 419 than the second boundary lines na1, na2 to nd1, and nd2). ing.
The present embodiment has the same effect as the first embodiment. Further, when the boundary portion between the main magnetic pole portion and the auxiliary magnetic pole portion passes through the teeth, it is possible to prevent the magnetic flux passing through the teeth from rapidly changing.

(Sixth embodiment)
A sixth embodiment is shown in FIG. In the sixth embodiment, a permanent magnet having a rectangular cross section perpendicular to the axial direction is inserted into a single layer magnet insertion hole having a linear cross section perpendicular to the axial direction.
In this embodiment, the rotor 510 (rotor core 511) has one magnet insertion hole 511a to 511d having a linear cross section perpendicular to the axial direction in each main magnetic pole part a to d. Layers are provided.
The magnet insertion hole 511a includes an outer wall 511a1, an inner wall 511a2, end walls 511a3 and 511a4, and inner side walls 511a5 and 511a6. A permanent magnet 512a having a rectangular cross section is inserted into the magnet insertion hole 511a.
In the present embodiment, the outer peripheral surface of the rotor 510 (rotor core 511) intersects the d-axis of the main magnetic pole portions a to d and has a first radius of curvature Rd centered on the center O of the rotor 510. Curve-shaped (arc-shaped) outer peripheral surfaces 510A to 510D having a second curvature radius Rq centering on the point Q intersecting with the q-axis of the auxiliary magnetic pole portions ab to da It is comprised by surface 510AB-510DA. The second radius of curvature Rq is set to be larger than the first radius of curvature Rd (Rq> Rd).
Further, in the outer peripheral surface (the outer peripheral surface corresponding to the auxiliary magnetic pole portions ab to da) 510AB to 510DA of the rotor 510 (rotor iron core 511), notches 510a1 are provided at locations facing the end walls of the magnet insertion holes 511a to 511d. , 510a2 to 510d1 and 510d2 are formed. Instead of forming the notch, a hole (including a gap) filled with a nonmagnetic material can be formed between the outer peripheral surface of the rotor 510 and the end wall of the magnet insertion hole.

In the present embodiment, as shown in FIG. 17, the line sa along the inner wall 511a2 of the magnet insertion hole 511a is parallel to the line sa, and the distance from the line sa to the rotation shaft insertion hole 519 side (rotation center O). A first region Ma corresponding to the magnet insertion hole 511a is formed by the first boundary line ma separated by W (= the teeth width T). Although not shown in FIG. 17, the inner walls 511b2 to 511d2 of the magnet insertion holes 511b to 511d and the first boundary lines mb to md similar to the first boundary line ma are used to form the magnet insertion holes 511b to 511b. First regions Mb to Md corresponding to 511d are formed.
Further, as shown in FIG. 17, the direction of the adjacent main magnetic pole portions b and d from the line sc along the inner wall 511c2 of the magnet insertion hole 511c and the point Pc where the line sc intersects the d axis of the main magnetic pole portion c. And the second boundary lines nc1 and nc2 having a gradient between the saturation magnetic flux density of the rotor 510 (rotor core 511) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 512c to the rotor 510 (rotor core 511). As a result, second regions Nc1 and Nc2 corresponding to the magnet insertion holes 511c are formed. Although not shown in FIG. 17, the inner walls 511a2, 511b2, and 511d2 of the magnet insertion holes 511a, 511b, and 511d and the second boundary lines na1, na2, and the second boundary lines nc1 and nc2, Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 511a, 511b, and 511d are formed by nb1, nb2, nd1, and nd2.
And the first region Ma to Md formed by the region X (for example, the first boundary lines ma to md and the lines sa to sd along the inner walls 511a2 to 511d2 of the magnet insertion holes 511a to 511d, and the second 2nd region Na1, Na2 to Nd1, Nd2) formed by boundary lines na1, na2 to nd1, nd2 and lines sa to sd along inner walls 511a2 to 511d2 of magnet insertion holes 511a to 511d. A communication hole is provided in Y (a region closer to the rotation shaft insertion hole 519 than the first boundary lines ma to md and a region closer to the rotation shaft insertion hole 519 than the second boundary lines na1, na2 to nd1, and nd2). ing.
The present embodiment has the same effect as the sixth embodiment. Moreover, it can prevent that the edge part of a permanent magnet is short-circuited.

(Seventh embodiment)
A seventh embodiment is shown in FIG. In the seventh embodiment, a permanent magnet having a rectangular cross section perpendicular to the axial direction is inserted into a single layer magnet insertion hole having a linear cross section perpendicular to the axial direction, and the outer periphery of the rotor The surface is configured by a curve having the same radius of curvature (configured in a cylindrical shape).
In the present embodiment, the rotor 610 (rotor core 611) has one magnet insertion hole 611a to 611d in which each main magnetic pole portion a to d has a linear cross-sectional shape perpendicular to the axial direction. Layers are provided. A permanent magnet 612a having a rectangular cross section is inserted into the magnet insertion hole 611a.
In the present embodiment, the outer peripheral surface of the rotor 610 (rotor core 611) is formed in a circular shape having a radius of curvature R around the rotation center O of the rotor 610.
In the present embodiment, the lines sa to sd along the inner walls 611a2 to 611d2 of the magnet insertion holes 611a to 611d are parallel to the lines sa to sd, and from the lines sa to sd to the rotating shaft insertion hole 619 side (rotation). First regions Ma to Md (not shown) corresponding to the magnet insertion holes 611a to 611d are formed by the first boundary lines ma to md separated by a distance W (= tooth width T) at the center O). Yes.
In the present embodiment, as shown in FIG. 18, the line sa along the inner wall 611a2 of the magnet insertion hole 611a is parallel to the line sa, and the distance from the line sa to the rotation shaft insertion hole 619 side (rotation center O). A first region Ma corresponding to the magnet insertion hole 611a is formed by the first boundary line ma separated by W (= the teeth width T). Although not shown in FIG. 18, the inner walls 611b2 to 611d2 of the magnet insertion holes 611b to 611d and the first boundary lines mb to md that are the same as the first boundary line ma are used. First regions Mb to Md corresponding to 611d are formed.
As shown in FIG. 18, the direction of the adjacent main magnetic pole portions b and d from the line sc along the inner wall 611c2 of the magnet insertion hole 611c and the point Pc where the line sc intersects the d axis of the main magnetic pole portion c. The second boundary lines nc1 and nc2 having a gradient between the saturation magnetic flux density of the rotor 610 (rotor core 611) and the magnetic flux density of the magnetic flux flowing from the permanent magnet 612c to the rotor 610 (rotor core 611). Thus, second regions Nc1 and Nc2 corresponding to the magnet insertion hole 611c are formed. Although not shown in FIG. 18, the inner walls 611a2, 611b2, 611d2 of the magnet insertion holes 611a, 611b, 611d, and the second boundary lines na1, na2, similar to the second boundary lines nc1, nc2, Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 611a, 611b, and 611d are formed by nb1, nb2, nd1, and nd2.
Then, the region X (for example, the first boundaries Ma to Md formed by the lines sa to sd along the inner walls 611a2 to 611d2 of the first boundary lines ma to md and the magnet insertion holes 611a to 611d, 2nd region Na1, Na2 to Nd1, Nd2) formed by boundary lines na1, na2 to nd1, nd2 and lines sa to sd along inner walls 611a2 to 611d2 of magnet insertion holes 611a to 611d A communication hole is provided in Y (a region closer to the rotation shaft insertion hole 619 than the first boundary lines ma to md and a region closer to the rotation shaft insertion hole 619 than the second boundary lines na1, na2 to nd1, and nd2). ing.
The present embodiment has the same effect as the first embodiment.

(Eighth embodiment)
An eighth embodiment is shown in FIG. In the eighth embodiment, the cross-sectional shape perpendicular to the axial direction is perpendicular to the axial direction in a two-layer magnet insertion hole having a V-shape that is concave in the outer peripheral direction (projecting in the central direction). A plurality of permanent magnets having a rectangular cross-sectional shape are inserted.
In the present embodiment, the rotor 710 (rotor core 711) has a cross-sectional shape perpendicular to the axial direction at each main magnetic pole portion ad to a concave shape in the outer peripheral direction (projecting in the central direction). Two V-shaped magnet insertion holes 711a1, 711a2 to 711d1, 711d2 are provided. That is, in the main magnetic pole part a, two layers of magnet insertion holes 711a1 and 711a2 are provided in the outer peripheral direction of the rotor 710 from the rotation shaft insertion hole 719.
The magnet insertion hole 711a2 includes outer walls 711a21 and 711a22, inner walls 711a23 and 711a24, and end walls 711a25 and 711a26. In addition, permanent magnets 712a21 and 712a22 having a rectangular cross section are inserted into the magnet insertion hole 711a2. The magnet insertion hole 711a1 has the same configuration as the magnet insertion hole 711a2.
In the present embodiment, as in the seventh embodiment, the outer peripheral surface of the rotor 710 is formed in a circular shape with a radius of curvature R centering on the center O of the rotor 710.

In the present embodiment, as shown in FIG. 19, the lines sa1, sa2 along the inner walls 711a23, 711a24 of the magnet insertion hole 711a2 are parallel to the lines sa1, sa2, and the rotation shaft insertion hole 719 extends from the lines sa1, sa2. First regions Ma1 and Ma2 corresponding to the magnet insertion holes 711a are formed by first boundary lines ma1 and ma2 that are separated by a distance W (= tooth width T) on the side (rotation center O). In addition, although illustration is abbreviate | omitted in FIG. 19, 1st boundary line mb1, mb2-md1 similar to inner wall 711b23 of magnet insertion hole 711b2-711d2, 711b24-711d23, 711d24, 1st boundary line ma1, ma2 , Md2, the first regions Mb1, Mb2-Md1, and Md2 corresponding to the magnet insertion holes 711b2 to 711d2 are formed.
Further, as shown in FIG. 19, the lines sc1 and sc2 along the inner walls 711c23 and 711c24 of the magnet insertion hole 711c2 and the point Pc where the lines sc1 and sc2 intersect the d axis of the main magnetic pole part c are adjacent to each other. The ratio between the saturation magnetic flux density of the rotor 710 (rotor core 711) and the magnetic flux density of the magnetic flux flowing from the permanent magnets 712c21, 712c22 to the rotor 710 (rotor core 711) is inclined. Second regions Nc1 and Nc2 corresponding to the magnet insertion holes 711c2 are formed by the second boundary lines nc1 and nc2. Although not shown in FIG. 19, the inner walls 711a23, 711a24, 711b23, 711b24, 711d23, 711d24 of the magnet insertion holes 711a2, 711b2, 711d2 and the second boundary lines nc1, nc2 are the same as the second boundary lines nc1, nc2. The boundary lines na1, na2, nb1, nb2, nd1, and nd2 form second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 corresponding to the magnet insertion holes 711a, 711b, and 711d.
Then, the region X (for example, the first boundary lines ma1, ma2-md1, md2 and the lines sa1, sa2-sd1, sd2 along the inner walls 711a23, 711a24-711d23, 711d24 of the magnet insertion holes 711a2-711d2 are formed. Lines sa1, sa2-sd1 along the first regions Ma1, Ma2-Md1, Md2 and the second boundary lines na1, na2-nd1, nd2 and the inner walls 711a23, 711a24-711d23, 711d24 of the magnet insertion holes 711a2-711d2. , Sd2 is not provided in the second region Na1, Na2 to Nd1, Nd2), and the region Y (the first boundary line ma1, ma2 to md1, md2 is a region closer to the rotation shaft insertion hole 719) The second boundary lines na1, na2 to nd1, and nd2 are closer to the rotation shaft insertion hole 719 side. It is provided communicating hole to pass).
This embodiment also has the same effect as the first embodiment.

(Ninth embodiment)
A ninth embodiment is shown in FIG. In the ninth embodiment, two magnet insertion holes are provided across the d-axis of the main magnetic pole portion.
In the present embodiment, the rotor 810 (rotor core 811) has a cross-sectional shape perpendicular to the axial direction formed in each main magnetic pole portion a to d to be concave in the outer peripheral direction (projecting in the central direction). Two magnet insertion holes 811a1, 811a2 to 811d1, 811d2 are provided so as to have a V shape. That is, the main magnetic pole part a is provided with magnet insertion holes 811a1 and 811a2 on both sides of the d-axis so as to be V-shaped.
The magnet insertion hole 811a1 includes an outer wall 811a11, an inner wall 811a12, an end wall 811a13, and a central wall 811a14. The magnet insertion hole 811a2 includes an outer wall 811a21, an inner wall 811a22, an end wall 811a23, and a central wall 811a24. Further, permanent magnets 812a1 and 812a2 having a rectangular cross section are inserted into the magnet insertion holes 811a1 and 811a2. Further, a bridge 811a3 is provided between the magnet insertion holes 811a1 and 811a2 (between the central walls 811a14 and 811a24). By this bridge 811a3, the holding force for holding the permanent magnets 812a1 and 812a2 in the magnet insertion holes 811a1 and 811a2 is increased, and the strength against the centrifugal force accompanying the rotation of the rotor 810 can be increased.
In the present embodiment, as in the seventh embodiment, the outer peripheral surface of the rotor 810 is formed in a circular shape having a radius of curvature R with the center O of the rotor 810 as the center.

In the present embodiment, as shown in FIG. 20, the lines sa1 and sa2 along the inner walls 811a12 and 811a22 of the magnet insertion holes 811a1 and 811a2 are parallel to the lines sa1 and sa2, and the rotation axes are inserted from the lines sa1 and sa2. A first region Ma is formed by the first boundary lines ma1 and ma2 separated by a distance W (= tooth width T) on the hole 819 side (rotation center O). Although not shown in FIG. 20, the inner walls 811b12, 811b22 to 811d12, 811d22 of the magnet insertion holes 811b1, 811b2 to 811d1, and 811d2, the first boundary line mb1 similar to the first boundary lines ma1 and ma2 , Mb2 to md1, and md2 form first regions Mb to Md.
As shown in FIG. 20, the lines sc1 and sc2 along the inner walls 811c12 and 811c22 of the magnet insertion holes 811c1 and 811c2 are adjacent to each other from the point Pc where the lines sc1 and sc2 intersect the d axis of the main magnetic pole part c. Extending in the direction of the main magnetic pole portions b and d, the ratio of the saturation magnetic flux density of the rotor 810 (rotor core 811) and the magnetic flux density of the magnetic flux flowing from the permanent magnets 812c1 and 812c2 to the rotor 810 (rotor core 811) is inclined. The second regions Nc1 and Nc2 are formed by the second boundary lines nc1 and nc2. Although not shown in FIG. 20, the inner walls 811a12, 811a22, 811b12, 811b22, 811d12, 811d22 of the magnet insertion holes 811a1, 811a2, 811b1, 811b2, 811d1, 811d2 and the second boundary lines nc1, nc2 Second regions Na1, Na2, Nb1, Nb2, Nd1, and Nd2 are formed by second boundary lines na1, na2, nb1, nb2, nd1, and nd2 that are the same as those in FIG.
Then, the region X (for example, lines sa1, sa2-sd1, sd2 along the first boundary lines ma1, ma2-md1, md2 and the inner walls 811a12, 811a22-811d12, 811d22 of the magnet insertion holes 811a1, 811a2-811d1, 811d2) The first region Ma to Md formed by the second boundary lines na1, na2 to nd1, nd2 and the lines sa1 along the inner walls 811a12, 811a22 to 811d12, 811d22 of the magnet insertion holes 811a1, 811a2 to 811d1, 811d2 , Sa2 to sd1, and sd2 are not provided in the second region Na1, Na2 to Nd1, and Nd2), and the region Y (the first boundary lines ma1, ma2 to md1, and md2 is closer to the rotating shaft insertion hole 819 side). A second boundary line na1, na2 to nd1, nd2 A communication hole is provided in a region closer to the rotation shaft insertion hole 819).

The present invention is not limited to the configuration described in the embodiment, and various changes, additions, and deletions are possible.
For example, the shape, number, and arrangement position of the magnet insertion holes can be changed as appropriate. It can also be formed in multiple layers.
The shape and number of permanent magnets inserted into the magnet insertion holes can be changed as appropriate.
Moreover, the shape of the outer peripheral surface of a rotor can be changed suitably.
Further, the shape of the outer peripheral surface of the rotor is not limited to the shape described in the embodiment. For example, the first curved surface having an arc shape that intersects the d-axis of the main magnetic pole part and centered on the center of the rotor, and the q-axis of the auxiliary magnetic pole part intersects with the center of the rotor, and the first It can also be constituted by an arc-shaped second curved surface having a different radius of curvature from the curved surface. In this case, the second curved surface is formed as a cutout portion formed by cutting out a virtual circular surface extending from the first curved surface.
A mode in which no communication hole is provided in the first region formed by the line along the first boundary line and the inner wall and the second region formed by the line along the second boundary line and the inner wall ( The communication hole is communicated with the first region formed by the first boundary line and the line along the inner wall. A mode in which no hole is provided (a mode in which a communication hole is provided on the rotary shaft insertion hole side from the first boundary line) or a second hole formed by a line along the second boundary line and the inner wall is not provided. Any one of the modes (a mode in which the communication hole is provided on the rotating shaft insertion hole side from the second boundary line) can also be used. Even if such a configuration is used, the permanent magnet motor is more in comparison with a case where the communication hole is provided in the rotor without considering at least one of the first area and the second area (when the communication hole is provided in the area X). The efficiency drop can be suppressed.
In addition, the first region is formed by a line along the first boundary line and the inner wall, and the second region is formed by a line along the second boundary line and the inner wall. The method of forming the region is not limited to this, and can be appropriately selected according to the cross-sectional shape of the magnet insertion hole. For example, when the magnet insertion hole has an inner side wall, a first region is formed by a first boundary line, a line along the inner wall, and a line along the inner side wall, and the second boundary line and The second region can be formed by a line along the inner wall and a line along the inner side wall (a region indicated by a right oblique line in FIGS. 3, 4, and 8). In this case, the method of forming the first region using the first boundary line and the line along the inner wall, as described in the embodiment, or the second boundary line and the line along the inner wall and the inner side wall Compared with the case of using the method of forming the second region, the first region and the second region can be formed more accurately, and the efficiency reduction can be further suppressed. Note that the first region is formed by the first boundary line, the line along the inner wall, and the line along the inner side wall, and the second boundary line, the line along the inner wall, and the line along the inner side wall. In the aspect of forming the second region, the first region is formed by a line along the first boundary line and the inner wall, and the second region is formed by a line along the second boundary line and the inner wall. include.
Further, as a mode in which the communication hole is not provided in the first region and the second region, the region is closer to the rotating shaft insertion hole side than the first boundary line, and closer to the rotating shaft insertion hole side than the second boundary line. A mode in which a communication hole is provided in the region, a mode in which a communication hole is provided in a region closer to the rotation shaft insertion hole than the first boundary line, or a region closer to the rotation shaft insertion hole than the second boundary line, and a rotor from the outer wall of the magnet insertion hole The aspect which provides a communicating hole in the area | region of the outer peripheral surface side of can be used.
Various permanent magnets can be used as the permanent magnet. In this case, the second boundary line is changed according to the magnetic flux density (design magnetic flux density) of the magnetic flux flowing from the permanent magnet to be used to the rotor (rotor core).
In the present invention, each configuration described in each embodiment can be used alone, or a plurality of configurations can be used in combination. For example, the shape, number and arrangement of the magnet insertion holes described in the embodiments can be combined with the configuration of the outer peripheral surface of the rotor as appropriate.
In the embodiment, the case where the stator and the rotor are provided with the communication holes that can be used as the cooling medium passage has been described, but the present invention can also be applied to the case where the communication passage is provided only in the rotor.
Although the case where the communication hole used as the cooling medium passage is provided has been described, the present invention can also be applied to the case where the communication hole used for other purposes is provided. For example, the present invention can be suitably applied to a case where a communication hole for flowing a cooling medium (for example, cooling air) for cooling the rotor is provided, a case where a communication hole for reducing the weight of the rotor is provided, or the like. Generally, when the rotor is constituted by a laminated iron core in which electromagnetic steel sheets are laminated, a caulking pin insertion hole for inserting a caulking pin for fixing the laminated body integrally is formed. The position of the caulking pin insertion hole is selected depending on the shape of the magnet insertion hole. The “rotor communication hole” of the present invention does not include a caulking pin insertion hole for inserting the caulking pin. When the caulking pin insertion hole is provided in the first region or the second region, for example, by using the caulking pin made of a magnetic material, the effect of suppressing the efficiency reduction of the present invention is prevented from being reduced. be able to.
Moreover, although the case where the permanent magnet motor is used as a compressor driving motor that drives a compressor such as an air conditioner or a refrigerator has been described, the permanent magnet motor according to the present invention is used as a motor that drives various other devices. be able to. For example, it can be used as an electric motor mounted on a vehicle such as an automobile. As an electric motor mounted on a vehicle such as an automobile, for example, an electric motor that drives the vehicle, an electric motor that drives an in-vehicle device (for example, a power window, a wiper, an electric seat, etc.) mounted on the vehicle, and the like correspond.

It is sectional drawing orthogonal to the axial direction of 1st Embodiment. It is detailed explanatory drawing of 1st Embodiment. It is a figure explaining the 1st boundary line. It is a figure explaining the 2nd boundary line. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 1st Embodiment. It is a figure which shows the [total area of a communicating hole-efficiency] characteristic at the time of providing a communicating hole in area | region X and Y. FIG. It is a figure which shows the rotor of 2nd Embodiment. It is a figure explaining the 1st boundary line and 2nd boundary line of 2nd Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 2nd Embodiment. It is a figure which shows the rotor of 3rd Embodiment. It is a figure explaining the 1st boundary line and 2nd boundary line of 3rd Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 3rd Embodiment. It is a figure which shows the rotor of 4th Embodiment. It is a figure explaining the 1st boundary line and 2nd boundary line of 4th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 4th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 5th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 6th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 7th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 8th Embodiment. It is a figure explaining the arrangement | positioning area | region of the communicating hole in 9th Embodiment. It is sectional drawing orthogonal to the axial direction of a prior art example.

Explanation of symbols

a, b, c, d Main magnetic pole part ab, bc, cd, da Auxiliary magnetic pole part ma, mb, mc, md, ma1, ma2 First boundary lines na1, na2, nb1, nb2, nc1, nc2, nd1, nd2 Second boundary lines Ma, Ma1, Ma2 First region Nc1, Nc2 Second region 10, 110, 210, 310, 410, 510, 610, 710, 810, 910 Rotor 10a1, 10a2, 10b1, 10b2 10c1, 10c2, 10d1, 10d2, 110a1, 110a2, 110b1, 110b2, 110c1, 110c2, 110d1, 110d2, 210a1, 210a2, 210b1, 210b2, 210c1, 210c2, 210d1, 210d2, 310a1, 310a2, 310b1, 310b2, 310c1 310c2, 31 0d1, 310d2, 510a1, 510a2, 510b1, 510b2, 510c1, 510c2, 510d1, 510d2 Notches 11a, 11b, 11c, 11d, 111a, 111b, 111c, 111d, 211a, 211b, 211c, 211d, 311a, 311b, 311c 311d, 411a, 411b, 411c, 411d, 511a, 511b, 511c, 511d, 611a, 611b, 611c, 611d, 711a1, 711a2, 711b1, 711b2, 711c1, 711c2, 711d1, 711d2, 811a1, 811a2, 8b , 811c1, 811c2, 811d1, 811d2, 911a, 911b, 911c, 911d Magnet insertion holes 11a1, 111a1, 211a1 211a2, 311a1, 411a1, 411b1, 411c1, 411d1, 511a1, 611a2, 711a21, 711a22, 811a11, 812a21 Outer wall 11a2, 111a2, 211a3, 211a4, 311a2, 411a2, 511a2, 611a2, 711a23, 711a11, 811a23, 711a11 11a4, 111a7, 111a8, 211a5, 211a6, 311a3, 311a4, 411a3, 411a4, 511a3, 511a4, 611a3, 611a4, 711a25, 711a26, 811a3, 811a23 End wall 11a5, 11a6, 111a5, 111a6, 411a11, 11a6, 411a11 , 611a5, 611a6 inner side wall 11a7, 11 8 Positioning protrusions 12a, 12b, 12c, 12d, 112a1, 112b1, 112c1, 112d1, 212a1, 212a2, 212b1, 212b2, 212c1, 212c2, 212d1, 212d2, 312a, 312b, 312c, 312d, 412a, 412b, 412c, 412d, 512a, 512b, 512c, 512d, 612a, 712a21, 712a22, 812a1, 812a2, 912a, 912b, 912c, 912d Permanent magnet 18 Communication hole 19, 119, 219, 319, 419, 519, 619, 719, 819, 919 Rotating shaft insertion hole 20, 120, 220, 320, 420, 520, 620, 720, 820, 920 Rotating shaft 30, 930 Stator 31, 931 Stator core (stator core)
32,932 Teeth 32a Teeth base 32b, 32c Teeth end 32d Teeth tip surface 33, 933 Slot 34a, 934a Notch 34, 934 Communication portion 40, 940 Ring (case)
111a3, 111a4 outer side wall

Claims (6)

A stator and a rotor are provided, and the stator is provided with teeth at positions facing the outer peripheral surface of the rotor. The rotor is provided with a rotation shaft insertion hole into which the rotation shaft is inserted. Further, when viewed in a cross section perpendicular to the axial direction, the main magnetic pole portions and the auxiliary magnetic pole portions are alternately arranged in the circumferential direction, and the main magnetic pole portion is provided with a magnet insertion hole into which a permanent magnet is inserted. A permanent magnet motor,
The rotor is provided with a communication hole communicating in the axial direction,
The communication hole is parallel to a line along the inner wall of the wall forming the magnet insertion hole, which is arranged closer to the rotation shaft insertion hole than the permanent magnet, and from the line along the inner wall to the rotation shaft insertion port side. The first boundary line formed by a line along the inner wall and the first boundary line separated by the teeth width, and the direction of the main magnetic pole part adjacent from the point intersecting the line along the inner wall and the d-axis of the main magnetic pole part And is formed by a second boundary line and a line along the inner wall that incline the ratio between the saturation magnetic flux density of the rotor and the magnetic flux density of the magnetic flux flowing from the permanent magnet inserted into the magnet insertion hole to the rotor. Not provided in the second region,
A permanent magnet motor characterized by that. A stator and a rotor are provided, and the stator is provided with teeth at positions facing the outer peripheral surface of the rotor. The rotor is provided with a rotation shaft insertion hole into which the rotation shaft is inserted. Further, when viewed in a cross section perpendicular to the axial direction, the main magnetic pole portions and the auxiliary magnetic pole portions are alternately arranged in the circumferential direction, and the main magnetic pole portion is provided with a magnet insertion hole into which a permanent magnet is inserted. A permanent magnet motor,
The rotor is provided with a communication hole communicating in the axial direction,
The communication hole is parallel to a line along the inner wall of the wall forming the magnet insertion hole, which is arranged closer to the rotation shaft insertion hole than the permanent magnet, and from the line along the inner wall to the rotation shaft insertion port side. A first region formed by a line along the inner wall and a first boundary line separated by a tooth width, or a line of the main magnetic pole part adjacent from a point intersecting the d axis of the main magnetic pole part and the line along the inner wall Formed by a line along the inner wall and a second boundary line extending in the direction and having an inclination of a ratio between the saturation magnetic flux density of the rotor and the magnetic flux density of the magnetic flux flowing from the permanent magnet inserted into the magnet insertion hole to the rotor Not provided in the second region to be
A permanent magnet motor characterized by that.   3. The permanent magnet motor according to claim 1, wherein an outer peripheral surface of the rotor intersects a d-axis of the main magnetic pole portion and is formed in a protruding shape in the outer peripheral direction, and an auxiliary The second curved surface that intersects with the q axis of the magnetic pole portion and is formed in a protruding shape in the outer peripheral direction is alternately connected, and the curvature of the second curved surface is larger than the curvature of the first curved surface. A permanent magnet motor characterized by being set.   The permanent magnet motor according to any one of claims 1 to 3, wherein the magnet insertion hole has an end wall arranged to face the outer peripheral surface of the rotor, and is provided on the outer peripheral surface of the rotor. The permanent magnet is characterized in that a notch is formed at a location facing the end wall of the magnet insertion hole, or a hole is provided between the outer peripheral surface of the rotor and the end wall of the magnet insertion hole. Electric motor.   5. The permanent magnet motor according to claim 1, wherein the main magnetic pole portion is provided with a plurality of layers of magnet insertion holes from the rotation shaft insertion hole toward the outer peripheral surface of the rotor, 1. The permanent magnet motor according to claim 1, wherein the first boundary line and the second boundary line are set based on an inner wall of a magnet insertion hole provided on the rotating shaft insertion hole side.   The permanent magnet motor according to any one of claims 1 to 5, wherein the rotor is made of an electromagnetic steel plate, a neodymium magnet is used as the permanent magnet, and the inclination of the second boundary line is 0.5. A permanent magnet motor characterized by being set.

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