JP2011147323A - Rotor for ipm motor, and ipm motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor, capable of completely sealing, at least, a gap between the side of slots for magnets formed in the rotor on the stator side, and the side of a permanent magnet on the stator side, with a very simple improved structure, and constituting an IPM motor having excellent motor performance (torque performance, rotation performance and motor efficiency). <P>SOLUTION: The permanent magnet 30 with a dimension smaller than the slot 12 is embedded in the slot 12 for magnets prepared in a rotor core 10. The rotor 100 for the IPM motor has two end plates 20, 20 at the end of the rotor core 10. A contact portion 40 (a protrusion) which abuts on at least part of the permanent magnets 30, is formed at a position corresponding to the slot 12 in the side 20a on the rotor core side in the end plates 20. The contact portion 40 abuts on the part of the permanent magnets 30, and further presses them. Thereby, at least the side 30a of the permanent magnet 30 on the stator side, is pressed to the side 12a of the slot on the stator side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotor for an embedded magnet type IPM motor and an IPM motor provided with the rotor.

  A magnet-embedded motor (hereinafter referred to as an IPM motor) in which a permanent magnet is embedded in a rotor can obtain a reluctance torque in addition to a magnet torque caused by the attractive force / repulsive force of a coil and a permanent magnet. Compared to a surface magnet type motor (SPM motor) in which a magnet is attached to the outer peripheral surface of the rotor, the torque is high and the efficiency is high. Therefore, this IPM motor is used for a drive motor of a hybrid vehicle, an electric vehicle and the like that require high output performance. As the permanent magnet, a sintered magnet such as a rare earth magnet, a ferrite magnet, or an alnico magnet is generally used.

  In the above-mentioned IPM motor, in order to prevent the permanent magnet from being smoothly inserted into the magnet slot formed in the rotor core and the permanent magnet from being damaged at the slot edge, the size of the slot is set to be larger than that of the permanent magnet. A method is generally used in which a permanent magnet is fixed by setting a large dimension, filling a resin of a nonmagnetic material into a resin filling slot on the side surface of the magnet slot, and curing the resin.

  However, since the size of the slot is larger than that of the permanent magnet, even if the side surface of the permanent magnet can be fixed with the resin of the non-magnetic material, the permanent magnet and the stator side surface of the slot are in contact with each other. There is no guarantee that the permanent magnet is fixed. For example, it is often the case that a filling resin enters and cures between the side surface of the slot on the side of the stator and the permanent magnet. The gap between the stator side surface of the magnet slot and the permanent magnet, and the resin material that has entered and hardened into the gap increase the magnetic resistance, thereby causing reluctance to enter the permanent magnet in the rotor from the stator side. As a result of the magnetic flux contributing to the torque and the magnetic fluxes contributing to the magnet torque flowing from the permanent magnet to the stator side being obstructed, the motor efficiency and output torque are reduced.

  In addition, regarding a conventional rotor for an IPM motor, a permanent magnet having a smaller dimension than that is inserted into a slot for a magnet, a groove for spring insertion is provided in the center of the rotor of the slot, and a spring is fixed thereto. Patent Documents 1 and 2 disclose techniques for pressing a permanent magnet against a stator side surface of a slot by a spring.

  According to these rotor configurations, although the gap between the permanent magnet and the side surface on the stator side of the magnet slot is eliminated, it is easy to understand that it is extremely difficult to provide a spring in the magnet slot. In general, providing a spring in a small-sized magnet slot itself is impractical, and if this is used for a drive motor of a hybrid vehicle whose production has recently been rapidly expanding, a rotor is required. It is considered that it cannot contribute to the increase in production.

  On the other hand, Patent Document 3 discloses a technique in which a permanent magnet is inserted into a slot having a large relative dimension and the slot is fixed with an O-ring. However, by using an O-ring, it is inevitable that a gap is formed between the side surface of the permanent magnet on the stator side and the side surface of the slot, and the magnetic resistance therebetween increases. .

JP 2000-175388 A JP 2000-341920 A JP 2009-38906 A

  The present invention has been made in view of the above-described problems, and relates to a rotor for an IPM motor in which a permanent magnet is inserted into a relatively large-sized magnet slot formed on the rotor. An object of the present invention is to provide an IPM motor rotor capable of effectively eliminating at least a gap between a stator side surface of a permanent magnet and a side surface of a magnet slot, and an IPM motor including the rotor. And

  In order to achieve the above object, an IPM motor rotor according to the present invention includes a permanent magnet embedded in a magnet slot provided in a rotor core and two end plates at the end of the rotor core. In the end plate, a position corresponding to the slot on the side surface on the rotor core side is provided with a contact portion that contacts at least a part of the permanent magnet, and the contact portion is a permanent magnet. In this case, at least the stator side surface of the permanent magnet is pressed against the stator side surface of the slot.

  In the rotor for an IPM motor of the present invention, a permanent magnet is inserted into the slot of a rotor having a slot for a magnet having a size larger than that of the permanent magnet, as in the conventional structure. In order to completely close an air gap that can be formed between the stator and the side surface of the stator on the slot, end plates arranged at both ends of the rotor core are respectively positioned at positions corresponding to the slots for the magnets and the permanent magnets. An abutting portion that abuts on the permanent magnet is provided, and at least the stator side surface of the permanent magnet is pressed against the stator side surface of the slot at the abutting portion. Thus, the present invention has a structure in which the stator side surface of the permanent magnet and the stator side surface of the magnet slot are completely in close contact with each other, thereby inhibiting the magnetic flux flow that contributes to the magnet torque flowing from the permanent magnet to the stator side. It is possible to eliminate the air gap and the like and to promote this magnetic flux flow.

  For example, when the planar shape of both the magnet slot provided in the rotor core and the permanent magnet is rectangular, the planar dimension relationship between the two is generally such that the permanent magnet is smoothly inserted into the slot. Each length of the vertical side and the horizontal side of the slot is longer than those of the permanent magnet. Usually, the shape of the magnet slot is reduced to the side of the magnet slot, and the resin filling slot for fixing the permanent magnet in the magnet slot communicates with the magnet slot. It is provided.

  However, in the rotor of the present invention, the end plate for capping the rotor core and the end surface of the permanent magnet that is capped at both ends of the rotor core is provided with a contact portion for pushing the permanent magnet as desired. In addition to being able to be pushed into at least the side surface of the magnet slot on the stator side, there is a synergistic effect that it is not necessary to fill the slot with a resin for fixing the permanent magnet.

  Here, as the form of the abutting portion formed on the end plate, there are roughly two forms.

  One of them is a form in which the contact portion is formed by a protrusion provided on the flat side surface of the end plate on the rotor core side.

  The protrusion enters the gap between the permanent magnet and the magnet slot. More specifically, the protrusion enters the gap on the rotor core center side of the permanent magnet and the magnet slot and presses the end plate. It is pressed against the side to bring both sides into close contact.

  In another embodiment, the contact portion includes an inclined portion that forms a concave groove formed in the side surface of the end plate on the rotor core side, and the end of the permanent magnet is the slot for the magnet. It protrudes in the said recessed groove from the edge part of this, and this protruding part contact | abuts to the said inclination part.

  The inclined portion may be a flat inclined surface or a curved inclined surface. In any form, the end portion of the permanent magnet protruding from the rotor core may be brought into contact with the inclined portion so that the permanent magnet is pressed against the side surface of the slot on the stator side.

  Depending on the arrangement of the permanent magnets arranged in the rotor, there are various forms, such as one magnetic pole formed from one permanent magnet, one formed from two or more permanent magnets, etc. . For example, a configuration in which two permanent magnets are arranged in a straight line in plan view to form one magnetic pole with a gap therebetween, and the two permanent magnets have a substantially V shape in plan view with a gap in between. It is composed of three permanent magnets in which one permanent magnet is disposed on the stator side of two permanent magnets having a substantially V-shape in a plan view, which are arranged in a shape to form one magnetic pole, The form which makes what is called Halbach arrangement can be mentioned.

  In the form in which two permanent magnets are arranged in a straight line in plan view with a gap therebetween to form one magnetic pole, when the size of the permanent magnet becomes large, the permanent magnet When this permanent magnet or outer bridge strength cannot withstand the acting centrifugal force, the large-sized permanent magnet is divided into two, and a center bridge is provided between the two, thereby acting on both permanent magnets. This is applied in order to reduce the force and simultaneously reduce the centrifugal force of the permanent magnet acting on the outer bridge.

  In the rotor of the present invention, in any of the forms in which one magnetic pole is formed from one permanent magnet, or in the form in which two permanent magnets are arranged linearly in plan view to form one magnetic pole. As described above, it suffices to have a structure in which at least the side surface on the stator side of the permanent magnet is pressed against the side surface on the stator side of the magnet slot by the contact portion formed on the end plate.

  However, in the embodiment in which the two permanent magnets are arranged in a substantially V shape in plan view with a gap therebetween to form one magnetic pole, the motor torque performance is improved while assuming the above basic configuration. In order to further increase, it is desirable to apply the following configuration. That is, for each of the two permanent magnets constituting the magnetic pole, the end plate is provided with at least two contact portions, and each of the two permanent magnets has its stator by at least two corresponding contact portions. The side surface on the side is pressed against the side surface on the stator side of the slot, and the side surface on the gap side (center bridge side) of the permanent magnet is pressed against the side surface on the gap side (center bridge side) of the slot. is there.

  According to verification by the present inventors, a motor having a rotor in which one magnetic pole is formed from two permanent magnets arranged in a V shape, the stator side surface of the permanent magnet is on the stator side of the magnet slot. It has been demonstrated that the highest motor torque can be obtained by closely contacting the side surface of the permanent magnet and the side surface on the gap side (center bridge side) of the permanent magnet to the side surface on the center bridge side of the magnet slot. .

  The rotor of the present invention may further include a side slot (corresponding to the resin filling slot of the conventional structure described above) communicating with the magnet slot provided in the rotor core. Well, by providing this side slot, a part of the above-mentioned projection enters the side slot, and the other part of the projection enters the magnet slot, so that the permanent magnet can be pushed in as desired. In addition, even if a side slot is provided, it is not necessary to dispose a resin material for fixing the permanent magnet in the slot.

  Further, in the embodiment having the side slots, the side slots are filled with a resin for fixing a permanent magnet as in the conventional structure, and have a heat dissipation property, including a resin material or a filler. The resin material may be filled and cured.

  For example, epoxy resin, polypropylene, polyethylene naphthalate, polyphenylene sulfide, polyimide, etc. can be used as this resin material, and fillers mixed to further improve heat dissipation include silica, alumina, boron nitride, silicon nitride. , Silicon carbide, magnesium oxide and the like.

Here, the permanent magnets embedded in the rotor of the present invention described above include rare earth magnets, ferrite magnets, alnico magnets, and the like. As the rare earth magnets, a three-component system in which iron and boron are added to neodymium. Examples thereof include a neodymium magnet, a samarium cobalt magnet made of a binary alloy of samarium and cobalt, a samarium iron nitrogen magnet, and a praseodymium magnet. Among these, rare earth magnets have a maximum energy product (BH) _max higher than that of ferrite magnets or alnico magnets, and therefore are suitable for application to drive motors such as hybrid vehicles that require high output.

  In addition, the rotor core is a steel sheet laminate formed by laminating electromagnetic steel sheets, iron, iron-silicon alloy, iron-nitrogen alloy, iron-nickel alloy, iron-carbon alloy, iron-boron alloy, Soft magnetic metal powder such as iron-cobalt alloy, iron-phosphorus alloy, iron-nickel-cobalt alloy and iron-aluminum-silicon alloy, or soft magnetic metal oxide powder is coated with a resin binder such as silicone resin. It can be formed from a dust core made of magnetic powder or the like, a high-density dust core (HDMC), or the like.

  The rotor for an IPM motor of the present invention described above is excellent in torque performance, rotational performance, and motor efficiency because there is no air gap that provides high magnetic resistance between the inner surface of the permanent magnet insertion slot and the permanent magnet. It becomes the rotor which comprises an IPM motor. Therefore, the production of the IPM motor having this rotor has recently been expanded, and it is suitable for a hybrid vehicle or an electric vehicle in which mounting of a high-performance drive motor is an urgent issue.

  As can be understood from the above description, according to the rotor for an IPM motor of the present invention, at least the gap between the stator side surface of the magnet slot formed in the rotor and the stator side surface of the permanent magnet, It is possible to manufacture a rotor that constitutes an IPM motor that can be completely closed with an extremely simple improved structure and thus has excellent motor performance (torque performance, rotational performance, motor efficiency).

(A) is a perspective view of one embodiment of the rotor of the present invention, and (b) is a bb arrow view of FIG. 1a. (A) is the perspective view which showed the side surface by the side of the rotor core of the end plate of FIG. 1a, (b) is the state in which the permanent magnet was pushed in the slot for magnets by the protrusion provided in the end plate. FIG. (A), (b) is the top view which showed other arrangement | positioning forms of the permanent magnet which comprises one magnetic pole in a rotor. It is the top view which showed other arrangement | positioning forms of the permanent magnet which comprises one magnetic pole in a rotor. (A), (b) is the top view which showed other arrangement | positioning forms of the permanent magnet which comprises one magnetic pole in a rotor. It is a longitudinal cross-sectional view of other embodiment of the rotor of this invention. (A)-(b) is the schematic diagram explaining the difference in the arrangement | positioning position of the permanent magnet in the slot for magnets among the analysis models applied by the magnetic field analysis.

  Embodiments of the present invention will be described below with reference to the drawings.

  1a is a perspective view of an embodiment of the rotor of the present invention, FIG. 1b is a view taken along the line bb in FIG. 1a, and FIG. 2a is a side view of the end plate of FIG. FIG. 2B is a diagram illustrating a state in which the permanent magnet is pushed into the magnet slot by the protrusion provided on the end plate.

  A rotor 100 for an IPM motor shown in FIG. 1 is formed by laminating disc-shaped electromagnetic steel plates 1,... And caulking them to form a rotor core 10. A drive shaft slot 11 is formed at the center of the rotor core 10. One permanent magnet 30 constituting one magnetic pole is inserted and fixed in the magnet slot 12 opened at the peripheral edge portion thereof, and end plates 20 and 20 are arranged at both ends of the rotor core 10. The whole is composed.

  The planar view shape of each magnet slot 12 is a horizontally long rectangle, and the permanent magnet 30 inserted through the slot 12 is a horizontally long rectangular shape having a smaller dimension than the slot 12. Therefore, the permanent magnet 30 can be in a posture that does not contact any side surface of the slot inside the magnet slot 12.

  On the side surface 20 a on the rotor core 10 side of the end plate 20, the gap between each permanent magnet 30 and the magnet slot 12 unique to each permanent magnet 30 in a position positioned at the end of the rotor core 10, More specifically, the abutting unit 40 composed of the two protrusions 41 and 41 is provided in the position that fits into the gap on the center side of both the rotor cores by the number of magnetic poles. The shape and radix of the protrusion 41 are not limited to the illustrated example.

  As shown in FIG. 2 b, in the posture in which the end plate 20 is disposed at the end of the rotor core 10, the protrusions 41, 41 provided on the side surface 20 a on the rotor core 10 side are between the permanent magnet 30 and the slot 12. And the stator side surface 30a of the permanent magnet 30 is pressed against the stator side surface 12a of the slot 12 (X2 direction of FIG. 3), thereby the stator side surface 12a of the slot 12 is pressed. The air gap that can occur is completely eliminated.

  Thus, the stator side surface 30a of the permanent magnet 30 is in close contact with the stator side surface 12a of the slot 12, which leads to the promotion of the magnetic flux flow contributing to the magnet torque flowing from the permanent magnet 30 to the stator side.

  Here, although not shown in the figure, a stator core is formed by laminating a magnetic steel plate, which is provided with a substantially annular yoke in plan view and teeth projecting radially inward from the yoke, and the stator core is formed inside the stator core. The illustrated rotor 100 is disposed, and a drive shaft (not shown) is inserted and fixed in a drive shaft slot 11 formed in the rotor 100, and this drive shaft is rotatably fixed by, for example, two bearing gears outside the rotor. Thus, an IPM motor is configured. In addition, both the illustrated rotor core 10 and the stator core (not shown) have iron, iron-silicon alloy, iron-nitrogen alloy, iron-nickel alloy, iron-carbon alloy, iron other than the form in which electromagnetic steel plates are laminated. -Soft magnetic metal powders such as boron alloys, iron-cobalt alloys, iron-phosphorus alloys, iron-nickel-cobalt alloys and iron-aluminum-silicon alloys, or soft magnetic metal oxide powders such as silicone resins It may be formed by a dust core made of magnetic powder coated with a resin binder.

  FIGS. 3 a, b, 4, 5 a, and b are all plan views showing other arrangements of permanent magnets constituting one magnetic pole in the rotor.

  First, in the magnetic pole form shown in FIG. 3A, two permanent magnets 30 and 30 are linearly arranged in a plan view to constitute one magnetic pole 30A, and each permanent magnet 30 has projections 41 and 41 together. The side surface 30a on the stator side is pressed against the side surface 12a on the stator side of the magnet slot 12 so that both are in close contact with each other.

  The magnetic pole form shown in FIG. 3a relates to the centrifugal force generated in the permanent magnet when the rotor rotates and the outer bridge of the rotor core on which the centrifugal force acts when the physique of the rotor and the motor is large and therefore the physique of the permanent magnet is also large. When it is judged that the rigidity of the permanent magnet or outer bridge cannot withstand the centrifugal force acting on them, the general permanent magnet is divided into two relatively small ones as shown in the figure, By providing the center bridge CB between the two, the centrifugal force acting on each permanent magnet is reduced, and the outer bridge and the center bridge can resist the centrifugal force.

  The magnetic pole form shown in FIG. 3b is one in which two permanent magnets 30 and 30 are arranged in a substantially V shape in plan view with a gap (center bridge CB) therebetween. .

  In this magnetic pole form, in addition to pressing the stator-side side surface 30 a of the permanent magnet 30 against the stator-side side surface 12 a of the slot 12 by the protrusion 41, a separate protrusion 41 is provided outside the slot 12 (outer bridge CB side). ′ Enters, and the side surface 30 b on the center bridge side of the permanent magnet 30 is held against the side surface 12 b on the center bridge CB side of the slot 12.

  That is, although not shown, the permanent magnet 30 is placed on the side of the V-shaped stator and on the center bridge CB side, as shown in FIG. The protrusions 41 and 41 ′ are provided at positions different from those in FIG.

  Analysis by the present inventors that the motor torque performance is further improved by positioning and fixing the permanent magnets 30 and 30 as shown in FIG. 3B in the magnetic pole configuration composed of V-shaped permanent magnets. Based on the results (described later).

  Also, the magnetic pole 30C of the form shown in FIG. 4 is composed of the permanent magnet 30 shown in FIG. 1 and the magnetic pole 30B made up of the permanent magnets 30 and 30 shown in FIG. It is a combined magnetic pole form, and a so-called Halbach arrangement.

  The magnetic pole forms shown in FIGS. 5a and 5b are all modifications of the magnetic pole form shown in FIG. 3b, both of which are side slots 13a on the center bridge side and outer bridge side of the magnet slot 12 and on the rotor central side. 13b, and the projections 42 'and 42 are partially fitted in the side slots 13a and 13b to push the permanent magnet 30 to the side surface 12a on the stator side and the side surface 12b on the center bridge side of the slot 12. It is a thing to guess.

  In the form of FIG. 5a, the side slots 13a and 13b remain formed with air gaps, whereas in the form of FIG. 5b, the side slots 13a and 13b are made of resin material 50 having heat dissipation. It is blocked.

  Here, examples of the material of the resin material 50 include an epoxy resin, polypropylene, polyethylene naphthalate, polyphenylene sulfide, polyimide, and the like. Further, in the case of mixing a filler in order to further improve heat dissipation, silica, alumina, It consists of a resin material in which fillers such as boron nitride, silicon nitride, silicon carbide, and magnesium oxide are mixed.

  The magnet slots 13a and 13b shown in the figure are preferably formed in a shape that can more effectively reduce the leakage magnetic flux that can be generated annularly from both ends of the permanent magnet 30 into the rotor core. As in the illustrated example, a substantially trapezoidal shape or a substantially triangular shape can be applied.

  FIG. 6 is a longitudinal sectional view of another embodiment of the rotor of the present invention. The illustrated rotor 100 </ b> A includes a concave groove 20 </ b> Aa having an inclined portion 20 </ b> Ab at a position corresponding to the permanent magnet 30 ′ and the magnet slot 12 of the end plate 20 </ b> A. When a long one is applied and disposed in the magnet slot 12, the tip protrudes from the rotor core 10 and is accommodated in the concave groove 20 </ b> Aa.

  Then, when the end plate 20A is disposed at the end of the rotor core 10 and the tip of the permanent magnet 30 ′ is accommodated in the groove 20Aa, the tip corner of the permanent magnet 30 ′ is the inclined portion 20Ab of the groove. The permanent magnet 30 'is pushed into the side surface on the stator side of the magnet slot (X3 direction).

[Analysis of the relationship between the position of the permanent magnets in the magnet slots and the motor torque, and the results, on the rotor model in which one magnetic pole is formed of two V-shaped permanent magnets]
The inventors of the present invention have found that when a relatively small-sized permanent magnet is disposed in a relatively large-sized magnet slot in a plan view, the permanent magnet is positioned at which position of the magnet slot. When the torque of the motor including the permanent magnet and the rotor is the largest, the magnetic field analysis was performed by modeling the V-shaped magnetic pole form in plan view with high magnetic pole application frequency.

  An outline of the analysis model regarding the magnetic pole is shown in FIGS. 7a to 7d. The magnetic pole model in the rotor model RM1 of FIG. 7a is such that, in the magnet slot SL, the side surface on the stator side and the center bridge CB side of the permanent magnet model MM are in close contact with the side surfaces on the stator side and center bridge side of the magnet slot. It is a thing. The magnetic pole model in the rotor model RM2 in FIG. 7b is one in which the permanent magnet model MM is not in close contact with any side surface of the magnet slot in the magnet slot SL. Further, the magnetic pole model in the rotor model RM3 of FIG. 7c is such that, in the magnet slot SL, the side surface on the side opposite to the stator of the permanent magnet model MM and the side surface on the outer bridge OB side and the outer side on the stator side of the magnet slot. It is in close contact with each side of the bridge side. Furthermore, the magnetic pole model in the rotor model RM4 of FIG. 7d is such that the side surface on the stator side and the outer bridge OB side of the permanent magnet model MM are the side surfaces on the stator side and outer bridge side of the magnet slot in the magnet slot SL. It is closely attached to.

  Each analysis model has 8 poles of each form shown in the rotor core, and conducts a magnetic field analysis by applying a current when the maximum torque is generated. A comparison of torque performance was attempted. The analysis results are shown in Table 1 below. In the table, the increase or decrease of the torque value of the other analysis model is shown with reference to the analysis result of the model of FIG. 7b, and a value larger than the analysis result of FIG. 7b is a positive value. The smaller ones are negative values and indicate the increment or decrement.

[Table 1]

  According to Table 1, the motor torques of the analysis models RM1 and RM4 in which the permanent magnet is in close contact with the side surface on the stator side of the magnet slot, the analysis model RM2 in which the side surface of the permanent magnet is not in close contact with any side surface of the magnet slot. It was proved from this analysis that it is increased by about 0.2 to 0.3% compared to the above. Furthermore, when comparing the analysis models RM1 and RM4, in addition to the permanent magnets being in close contact with the side surface on the stator side of the magnet slot, the permanent magnet is in close contact with the side surface on the center bridge side, thereby being in close contact with the side surface on the outer bridge side. It has been proved that the torque is increased by about 0.1% as compared to the case of doing so.

  From this analysis result, it is preferable from the viewpoint of motor torque performance that at least the stator side surface of the permanent magnet is in close contact with the stator side surface of the magnet slot, and in particular, one magnetic pole has two V-shaped arrangements. In the case of permanent magnets, it has been demonstrated that each permanent magnet is preferably in close contact with both the stator side surface and the center bridge side surface of the magnet slot in terms of motor torque performance.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Electromagnetic steel sheet, 10 ... Rotor core, 11 ... Drive shaft slot, 12 ... Magnet slot, 12a ... Side surface on the stator side of magnet slot, 12b ... Side surface on the center bridge side of magnet slot, 20, 20A ... End plate , 20a ... rotor core side surface, 20Aa ... concave groove, 20Ab ... contact part (inclined part), 21 ... shaft hole, 30, 30 '... permanent magnet, 30A, 30B, 30C ... one magnetic pole, 30a ... stator of permanent magnet Side surface, 30b... Side surface on the center bridge side of the permanent magnet, 40... Contact portion unit (projection unit), 41... Contact portion (projection), 41 '. Resin material, 100, 100A ... rotor for IPM motor

Claims (8)

A rotor for an IPM motor, wherein a permanent magnet is embedded in a magnet slot provided in a rotor core, and two end plates are provided at an end of the rotor core,
Of the end plate, a position corresponding to the slot on the side surface on the rotor core side is provided with a contact portion that contacts at least a part of the permanent magnet,
A rotor for an IPM motor, wherein at least the stator side surface of the permanent magnet is pressed against the stator side surface of the slot by the contact portion abutting against and further pressing the part of the permanent magnet.   The rotor for an IPM motor according to claim 1, wherein the contact portion is a protrusion provided on the flat side surface of the end plate on the rotor core side.   The contact portion is an inclined portion that forms a groove formed on the side surface of the end plate on the rotor core side, and the end of the permanent magnet protrudes from the end of the magnet slot into the groove. The rotor for an IPM motor according to claim 1, wherein the protruding portion is in contact with the inclined portion. The two permanent magnets are arranged in a straight line in plan view with a gap therebetween to form one magnetic pole,
The IPM motor according to any one of claims 1 to 3, wherein a side surface on the stator side of each of the two permanent magnets is pressed against a side surface on the stator side of the slot by each of the two contact portions for each magnetic pole. Rotor. The two permanent magnets are arranged in a substantially V shape in plan view with a gap therebetween to form one magnetic pole,
For each of the two permanent magnets constituting the magnetic pole, the end plate is provided with at least two contact portions, and each of the two permanent magnets is provided on the stator side by at least two corresponding contact portions. The IPM motor according to claim 1, wherein a side surface is pressed against a side surface of the slot on the stator side, and a side surface of the permanent magnet on the gap side is pressed against a side surface of the slot on the gap side. Rotor. The rotor core further includes a side slot that communicates with a side of the magnet slot,
6. The IPM motor according to claim 2, wherein a part of the protrusion enters the side slot and the other part of the protrusion enters the magnet slot. Rotor.   The rotor for an IPM motor according to claim 6, wherein either one of a resin material or a filler-containing resin material having heat dissipation is accommodated in the side slot.   An IPM motor comprising at least the rotor according to claim 1.

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