JP2012157090A - Magnet embedded rotor and motor - Google Patents

Abstract

A rotor adopting an IPM type structure that can reduce a leakage magnetic flux and improve motor torque.
A magnet magnetic pole 26 configured to embed a permanent magnet 23 in a rotor 20 includes an inner magnetic pole portion 27 that is integrally formed with a rotor core 21 and provided radially inside the permanent magnet 23, and a diameter of the permanent magnet 23. The inner magnetic pole part 27 is provided on the outer side in the direction, and the outer magnetic pole part 28 is provided separately. The cover members 24 and 25 provided on both sides of the rotor core 21 in the axial direction hold both end portions in the axial direction of the outer magnetic pole portion 28 so as to hold the permanent magnet 23 with the inner and outer magnetic pole portions 27 and 28 sandwiched therebetween. Composed. The inner magnetic pole portion 27 and the outer magnetic pole portion 28 are fixed in a state where the peripheral edge portions at both ends in the circumferential direction of the permanent magnet 23 are separated from each other without contact.
[Selection] Figure 2

Description

  The present invention relates to a magnet-embedded rotor and a motor including the rotor.

  As a rotor used in a motor, a magnet-embedded (hereinafter referred to as IPM) rotor is known. As an IPM type rotor, for example, as shown in Patent Document 1, accommodation holes (axial direction holes) are formed at predetermined intervals in the circumferential direction in a rotor core in which a plurality of core sheets are laminated. Some have a permanent magnet inserted to form a magnetic pole. In the rotor having such a structure, holding members (base members) are provided on both sides in the axial direction of the rotor core, and the permanent magnet and the rotor core are held from both sides in the axial direction by the holding members.

Japanese Patent No. 4163935

  By the way, in the rotor of said IPM type structure, it is set as the structure which inserts a permanent magnet in an accommodation hole, and has comprised the frame shape where a part of rotor core of the edge part periphery of a permanent magnet was connected to radial direction. Therefore, a leakage magnetic flux is generated in a part of the rotor core at the peripheral edge of the end portion, and the effective magnetic flux of the permanent magnet is reduced.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce the leakage magnetic flux and improve the motor torque in a rotor adopting an IPM type structure, and its It is providing the motor provided with a rotor.

  In order to solve the above problems, the invention according to claim 1 is configured such that a plurality of magnet magnetic poles are formed in the circumferential direction of the rotor core so as to face the magnetic poles of the stator, and permanent magnets are embedded in the magnet magnetic poles. An embedded magnet type rotor, wherein the magnet magnetic pole is formed integrally with the rotor core and provided on the anti-stator side of the permanent magnet, and the permanent magnet is provided on the stator side of the permanent magnet. A stator-side magnetic pole portion that is separable from the anti-stator-side magnetic pole portion so that the magnet housing portion can be opened, and holding members provided on both sides in the axial direction of the rotor core respectively The gist of the invention is that the end portion in the axial direction of the magnetic pole portion is held and the permanent magnet is sandwiched and held between the stator side magnetic pole portion and the anti-stator side magnetic pole portion.

  According to the present invention, in a so-called IPM type rotor, the magnet magnetic pole configured in such a manner that the permanent magnet is embedded is anti-stator-side magnetic pole formed integrally with the rotor core, and the permanent magnet accommodating portion can be opened. The stator side magnetic pole part is configured to be separable from the stator side magnetic pole part. Then, both axial end portions of the stator side magnetic pole portion are held by holding members provided on both sides of the rotor core in the axial direction, and the permanent magnet is sandwiched and held between the anti-stator side magnetic pole portion and the stator side magnetic pole portion. That is, since the anti-stator side magnetic pole part and the stator side magnetic pole part are separated from each other, the magnetic resistance between the magnetic pole parts is increased, so that the leakage magnetic flux that can be generated at the peripheral edge of the permanent magnet is reduced. As a result, the effective magnetic flux of the permanent magnet is increased, and the motor torque can be improved. In addition, the magnet magnetic pole is configured by holding the permanent magnet between the stator side magnetic pole part and the anti-stator side magnetic pole part so as to hold a clearance (clearance) between the permanent magnet and the stator side and the anti-stator side magnetic pole part. ) Is extremely small. This also leads to an increase in the effective magnetic flux of the permanent magnet and, consequently, an improvement in motor torque.

  According to a second aspect of the present invention, in the magnet-embedded rotor according to the first aspect, the holding member is formed in an axial direction so as to insert and hold an axial end of the stator side magnetic pole portion. The gist of this is that an additional insertion portion is provided.

  In this invention, the holding member is provided with an insertion portion formed in the axial direction, and both axial end portions of the stator side magnetic pole portion are inserted into the insertion portions of the holding member provided on both sides in the axial direction, respectively. Retained. Thereby, the structure which hold | maintains a stator side magnetic pole part can be made into a simple structure.

  According to a third aspect of the present invention, in the magnet-embedded rotor according to the second aspect, the insertion portion has a press-fitted portion that press-contacts with a stator side portion of the stator side magnetic pole portion, and the stator side magnetic pole portion The gist of the invention is that a gap is formed between the non-stator side portion.

  In the present invention, the insertion portion is provided with a press-fitting portion that is in pressure contact with the stator side portion of the stator side magnetic pole portion, and is configured such that a gap is formed between the stator side magnetic pole portion and the non-stator side portion. As a result, when the stator side magnetic pole part is press-fitted into the insertion part, the end of the stator side magnetic pole part can escape to the gap side, so that the press-fitting operation is facilitated and dimensional errors and the like are absorbed. Can do.

  In invention of Claim 4, in the magnet-embedded rotor according to Claim 2 or 3, a part of the circumferential direction at the axial end of the stator side magnetic pole is inserted into the insertion part, The gist of the present invention is that the holding member is provided with an opening portion that exposes a portion other than the stator side magnetic pole portion inserted to the stator side.

  In this invention, a part of the circumferential direction at the axial end portion of the stator side magnetic pole portion is inserted into the insertion portion provided in the holding member. The holding member is provided with an opening portion that exposes a portion other than the stator side magnetic pole portion inserted to the stator side. As a result, the stator-side magnetic pole portion can widen the magnetic flux generation surface directly facing the stator by exposing the portion other than the circumferentially inserted portion at the axial end to the stator side from the opening portion, The effective magnetic flux can be increased.

  According to a fifth aspect of the present invention, in the magnet-embedded rotor according to any one of the second to fourth aspects, the stator-side magnetic pole portion is arranged on the stator side surface between the axial directions of the holding member. The gist of the invention is that a protruding portion that protrudes toward the stator side from a portion to be inserted into the stator is provided.

  In this invention, the stator side magnetic pole portion is provided with a protruding portion that protrudes toward the stator side from the portion inserted into the insertion portion on the stator side surface between the axial directions of the holding member. Thereby, since the clearance gap between a stator side magnetic pole part and a stator becomes small in the protrusion part, the increase in an effective magnetic flux can be aimed at.

  According to a sixth aspect of the present invention, in the magnet-embedded rotor according to any one of the first to fifth aspects, at least one of the holding members provided on both axial sides of the rotor core protrudes in the axial direction. The gist of the present invention is that engagement portions that engage with both sides of the magnet magnetic pole in the circumferential direction are provided.

  In this invention, at least one of the holding members provided on both axial sides of the rotor core is provided with an engaging portion that protrudes in the axial direction and engages with both circumferential sides of the magnet magnetic pole. Thereby, since a permanent magnet is hold | maintained also from the circumferential direction both sides by an engaging part, the position shift etc. of a permanent magnet can be prevented reliably.

According to a seventh aspect of the present invention, there is provided a motor including the magnet embedded rotor according to any one of the first to sixth aspects.
According to the present invention, it is possible to provide a motor in which leakage magnetic flux is reduced and motor torque is improved.

  ADVANTAGE OF THE INVENTION According to this invention, in the rotor which employ | adopted IPM type structure, the reduction of a leakage magnetic flux can be aimed at and the motor provided with the rotor which can improve motor torque can be provided.

It is a schematic block diagram of the motor in this embodiment. It is a disassembled perspective view of the rotor in this embodiment. It is sectional drawing of the rotor in this embodiment. (A) is sectional drawing of the rotor in another example, (b) is a perspective view which shows the assembly | attachment of the cover member and outer side magnetic pole part in another example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown in FIG. 1, the motor M of the present embodiment is an inner rotor type brushless motor, and is configured by accommodating a stator 2 and a rotor 20 inside a motor case 1. The motor case 1 includes a bottomed cylindrical case body 3 and a substantially disc-shaped cover plate 4 that closes an opening of the case body 3. An annular stator 2 is fixed to the inner peripheral surface of the case body 3, and a winding magnetic pole 6 for generating a rotating magnetic field for rotating the rotor 20 is wound around the teeth 5 of the stator 2. .

  A rotor 20 having a rotation shaft 7 is disposed inside the stator 2. A base end portion of the rotary shaft 7 formed in a substantially cylindrical shape is supported by a bearing 8 provided at the center of the bottom of the case body 3, while a tip side portion of the rotary shaft 7 is formed on the cover plate. 4 is supported by a bearing 9 provided at a central portion in the radial direction. Further, the distal end portion of the rotary shaft 7 penetrates the central portion in the radial direction of the cover plate 4 and protrudes to the outside of the motor case 1.

  As shown in FIGS. 1 and 2, a substantially cylindrical rotor core 21 is disposed on the rotating shaft 7 at a portion closer to the base end than the central portion in the axial direction so as to face the stator 2 in the radial direction. ing. The rotor core 21 is composed of a core main body portion 21 a in which an inner magnetic pole portion 27 and a salient pole 31 described later are integrally formed, and an outer magnetic pole portion 28. The core body portion 21a is formed by laminating a plurality of core sheets 22 made of a magnetic metal plate in the axial direction and connecting them together by caulking, and a permanent magnet 23 is disposed in contact with the outer peripheral surface along the axial direction. Yes. The rotor 20 includes a cover member 24 disposed on the proximal end side of the rotor core 21 and a cover member 25 disposed on the distal end side of the rotor core 21 so as to face the cover member 24 in the axial direction of the rotor core 21. Located on both sides. The rotor 20 has a structure in which the cover members 24 and 25 hold the end portions in the axial direction of the outer magnetic pole portion 28, and the permanent magnet 23 is held between the outer magnetic pole portion 28 and the inner magnetic pole portion 27. ing.

  Between the rotor core 21 and the bearing 9 in the rotating shaft 7, a sensor magnet 11 formed in an annular shape and having a plurality of magnetic poles in the circumferential direction is fixed. On the other hand, a circuit board 12 is fixed to the inner side surface 4a of the cover plate 4, and a magnetic sensor 13 made of, for example, a Hall IC is disposed on the circuit board 12 at a position facing the sensor magnet 11 in the axial direction. Has been. The magnetic sensor 13 detects a magnetic field change accompanying the rotation of the sensor magnet 11 in order to detect the rotational position of the rotor 20.

Next, the configuration of the rotor 20 will be described in detail.
The rotor core 21 (core main body portion 21a) is formed in an annular shape and is provided with a press-fitting hole 21b at the center, and is fixed to the rotary shaft 7 by press-fitting the rotary shaft 7 into the press-fitting hole 21b. Four magnet magnetic poles 26 on which the permanent magnets 23 are arranged are formed on the outer peripheral portion of the rotor core 21 in the circumferential direction (at intervals of 90 °). Each magnet magnetic pole 26 is formed integrally with the core body portion 21 a of the rotor core 21 and is provided on the inner side of the permanent magnet 23 in the radial direction (on the opposite side of the stator) (on the opposite side of the stator) 27. The inner magnetic pole portion 27 is arranged on the radially outer side (stator side) and is formed of an outer magnetic pole portion (stator side magnetic pole portion) 28 provided separately. The inner magnetic pole portion 27 has a convex shape projecting radially outward, and a tip portion of the convex shape forms a flat surface 27a, and the permanent magnets 23 are arranged on each flat surface 27a (four in total). Yes. The permanent magnet 23 is formed in a substantially rectangular parallelepiped shape, and the longitudinal direction is arranged along the axial direction. The inner flat surface 23 a on the radially inner side of the permanent magnet 23 is disposed in contact with the flat surface 27 a of the inner magnetic pole portion 27.

  Outside the permanent magnet 23 in the radial direction, an outer magnetic pole portion 28 having a rectangular plate shape is disposed. The outer magnetic pole part 28 is configured by laminating a plurality of substantially rectangular parallelepiped core members 29 made of magnetic metal plates in the circumferential direction and connecting them by caulking. The outer flat surface 23 b on the outer side in the radial direction of the permanent magnet 23 is disposed in contact with the flat surface 28 a on the inner side in the radial direction of the outer magnetic pole portion 28.

  The inner and outer magnetic pole portions 27 and 28 are formed to have the same circumferential length as the permanent magnet 23. Moreover, each inner magnetic pole part 27 and the permanent magnet 23 are comprised so that the length of an axial direction may become the same length. The inner and outer magnetic pole portions 27 and 28 sandwich the permanent magnet 23 from both sides in the radial direction, and house the permanent magnets 23 in an embedded manner to constitute the magnet magnetic pole 26. Even if the permanent magnet 23 is embedded in this way, the outer magnetic pole portion 28 can be assembled so that the permanent magnet 23 can be assembled with the housing portion of the permanent magnet 23 opened by the separation structure. The assembling work is easy, and the permanent magnet 23 is assembled so as to be able to contact the inner magnetic pole part 27 and the outer magnetic pole part 28 without any gap.

  The magnet magnetic pole 26 is configured to project radially outward, and the inner and outer magnetic pole portions 27 and 28 and both end portions in the circumferential direction of the permanent magnet 23 are from the magnetic pole center line of the magnet magnetic pole 26 (from the center position of the outer flat surface 23b). (A line extending in the radial direction). Between the projecting magnet magnetic poles 26, salient poles 31 integrally formed on the outer periphery of the rotor core 21 are formed with gaps K having a certain area when viewed from the magnetic pole 26 in the axial direction. Incidentally, the gap K has a circumferential surface composed of the side surface of the magnet magnetic pole 26 and the side surface of the salient pole 31, and the width in the circumferential direction becomes wider from the radially inner side toward the outer opening portion. It has a shape.

  On substantially both sides of the rotor 20 in the axial direction, substantially disk-shaped cover members 24 and 25 are arranged. Each of the cover members 24 and 25 has an outer diameter equal to the outer diameter of the rotor core 21 (in this case, the outer diameter at the salient pole 31 portion). The cover members 24 and 25 are respectively provided with fixing holes 24a and 25a in the central portion in the radial direction, and are fixed to the rotating shaft 7 by press-fitting the rotating shaft 7 into the fixing holes 24a and 25a. . Both cover members 24 and 25 are fixed so as to be integrally rotatable with the rotary shaft 7 and the rotor core 21 when the rotary shaft 7 is press-fitted.

  Each cover member 24, 25 has an engagement portion 24 b that protrudes in the axial direction and has a cross-sectional shape formed in accordance with the fan shape of the gap K and engages with each magnetic pole 26, 31 and both circumferential ends of the permanent magnet 23. 25b are provided. Each cover member 24, 25 has an insertion groove 24c, 25c having a substantially rectangular cross-sectional shape so as to insert and hold the axial end portion of the outer magnetic pole portion 28 in the circumferential direction. Each is formed in accordance with the position of the magnetic pole 26 (four in total). The insertion grooves 24 c and 25 c are provided as press-fitting portions where the outer side surfaces 24 d and 25 d located on the radially outer side are pressed against the axial end of the flat surface 28 b on the same side of the outer magnetic pole portion 28. The cover members 24 and 25 are fixed to the rotary shaft 7 so that the side surfaces 24d and 25d of the insertion grooves 24c and 25c and the flat surface 28b on the outer side of the outer magnetic pole portion 28 are in pressure contact with each other. As a result, the outer magnetic pole portion 28 is fixed so that the permanent magnet 23 is sandwiched between the magnetic pole portion 28 itself and the inner magnetic pole portion 27.

  Further, in the attached state of the cover members 24 and 25, the engaging portions 24 b and 25 b provided in the vicinity of the insertion grooves 24 c and 25 c abut on both end portions in the circumferential direction of the magnetic poles 26 and 31 and the permanent magnet 23. Further, the surfaces of the cover members 24 and 25 on the rotor core 21 side also abut on the axial end surfaces of the rotor core 21 and the permanent magnet 23. Thus, the permanent magnet 23 is not only held in the radial direction by the outer magnetic pole portion 28 and the inner magnetic pole portion 27 but also held in the circumferential direction and the axial direction (movement restriction).

  Incidentally, as shown in FIG. 3, the groove width (radial length) of each of the insertion grooves 24c and 25c is formed to be larger than the thickness of the outer magnetic pole portion 28, and is located radially inward. A gap S is formed between the inner side surfaces 24e, 25e of the insertion grooves 24c, 25c and the radially inner flat surface 28a of the outer magnetic pole portion 28. The gap S functions as a clearance space when the axial end of the outer magnetic pole portion 28 is inserted into the insertion grooves 24c and 25c. Further, in each cover member 24, 25, since the insertion grooves 24c, 25c are located inside the radially outer portions 24f, 25f, the outer magnetic pole portion 28 (inserted in the insertion grooves 24c, 25c) The magnet magnetic pole 26) is in a position slightly retracted inward from the outermost periphery of the rotor 20.

  In such a rotor 20, the permanent magnets 23 are arranged so that the radially outer surface is N-pole, the magnet magnetic pole 26 is configured as an N-pole magnetic pole, and salient poles 31 between the magnet magnetic poles 26. Is a so-called consequent pole type (half magnet type) having eight magnetic poles at equal intervals of 45 °. Further, since the permanent magnet 23 is assembled in a manner of being embedded in the rotor core 21, the rotor 20 is a magnet embedded rotor, and the brushless motor M is also a so-called IPM type motor.

Next, the operation of this embodiment will be described.
In the rotor 20 of the present embodiment, the magnet magnetic pole 26 is constituted by a separate body of the inner magnetic pole portion 27 and the outer magnetic pole portion 28, and is arranged so that the permanent magnet 23 is sandwiched between the radial directions. In this case, the inner and outer magnetic pole portions 27 and 28 are in a state in which the peripheral edge portions in the circumferential direction of the permanent magnet 23 are not abutted and separated. As a result, the rotor 20 has a high mutual magnetic resistance due to the non-contact of the inner and outer magnetic pole portions 27 and 28, so that the leakage magnetic flux that can be generated at the peripheral edge of the permanent magnet 23 is reduced. The effective magnetic flux 23 is increased. In addition, it becomes possible to reduce leakage magnetic flux more suitably by forming each cover member 24, 25 with a non-magnetic material.

  Further, both end portions in the axial direction of the outer magnetic pole portion 28 are press-fitted into the insertion grooves 24c and 25c of the cover members 24 and 25, respectively, and the outer magnetic pole portion 28 is fixed, so that the permanent magnet 23 is located on the inner and outer sides. The magnetic pole portions 27 and 28 are suitably held by holding pressure. Here, in the rotor of the conventional IPM type structure in which the permanent magnet is inserted into the accommodation hole of the rotor core, it is necessary to smoothly insert the permanent magnet into the slit portion. A clearance (clearance) is set between the side surface. This is one factor that reduces the effective magnetic flux of the permanent magnet 23 and thus reduces the motor torque. On the other hand, in the present embodiment, the permanent magnet 23 and the inner and outer magnetic pole portions 27 and 28 are in contact with each other without any gap, and this also increases the effective magnetic flux of the permanent magnet 23. Yes.

Next, characteristic effects of the present embodiment will be described.
(1) In the rotor 20 of the present embodiment, the magnet magnetic pole 26 configured to embed the permanent magnet 23 is provided separately from the inner magnetic pole portion 27 formed integrally with the rotor core 21 and the inner magnetic pole portion 27. And an outer magnetic pole portion 28. The cover members 24 and 25 provided on both sides of the rotor core 21 in the axial direction hold both end portions in the axial direction of the outer magnetic pole portions 28, and the permanent magnets 23 are held between the inner and outer magnetic pole portions 27 and 28. The And the inner side magnetic pole part 27 and the outer side magnetic pole part 28 are fixed in the state which the circumferential direction both-ends peripheral part of the permanent magnet 23 was spaced apart by non-contact. Thereby, since the mutual magnetic resistance of the rotor 20 is increased by making the inner and outer magnetic pole portions 27 and 28 non-contact with each other, the leakage magnetic flux that can be generated at the peripheral edge of the permanent magnet 23 is reduced. As a result, the effective magnetic flux of the permanent magnet 23 is increased, and the motor torque can be improved.

  (2) The magnet magnetic pole 26 is constituted by holding the permanent magnet 23 from both sides in the radial direction with the inner and outer magnetic pole portions 27 and 28 so that the permanent magnet 23 is connected to the inner and outer magnetic pole portions 27 and 28. The gap (clearance) between them becomes extremely small. Thereby, the effective magnetic flux of the permanent magnet 23 can be increased, and the motor torque can be improved.

  (3) The cover members 24 and 25 are provided with insertion grooves 24c and 24c that are recessed in the axial direction, and the outer sides of the insertion grooves 24c and 24c of the cover members 24 and 25 provided on both sides in the axial direction. Both end portions in the axial direction of the magnetic pole portion 28 are inserted to hold the outer magnetic pole portion 28. Thereby, the structure which hold | maintains the outer magnetic pole part 28 can be made into a simple structure.

  (4) Side surfaces 24d and 25d that press-contact the flat surface 28b of the outer magnetic pole portion 28 are provided in the insertion grooves 24c and 25c. Each of the insertion grooves 24 c and 25 c has a groove width (a length in the radial direction) larger than a thickness of the outer magnetic pole part 28 so that a gap S is formed between the outer magnetic pole part 28 and the flat surface 28 a on the radially inner side. It is configured to be large. As a result, when the outer magnetic pole portion 28 is press-fitted into the insertion grooves 24c and 25c, the end of the outer magnetic pole portion 28 can escape to the gap S side. Can be absorbed.

  (5) The cover members 24 and 25 provided on both axial sides of the rotor core 21 are provided with engaging portions 24b and 25b that protrude in the axial direction and engage with both circumferential sides of the magnet magnetic pole 26, respectively. Thereby, since the permanent magnet 23 is hold | maintained also from the circumferential direction both sides by the engaging parts 24b and 25b, the position shift of the permanent magnet 23 etc. can be prevented reliably.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the flat surface 28b of the outer magnetic pole portion 28 is inserted into the insertion grooves 24c, 25c of the cover members 24, 25 so as to be in pressure contact over the entire circumferential direction, but the present invention is not limited to this.

  For example, as shown in FIGS. 4A and 4B, the insertion grooves 24c and 25c are changed to a configuration in which only both corners (parts in the circumferential direction) at the axial end of the outer magnetic pole portion 28 are inserted into the insertion grooves 24c and 25c. Further, openings 24g and 25g are provided in the radially outer portions 24f and 25f outside the insertion grooves 24c and 25c so that the central portion of the axial end of the outer magnetic pole portion 28 is exposed radially outward (to the stator 2 side). May be. In this case, the outer magnetic pole portion 28 is provided with a recessed portion 28c having a concave shape radially inward at both corners of both axial end portions, in other words, a portion other than the recessed portion 28c bulges radially outward. It has a shape. The outer magnetic pole portion 28 is press-fitted into the insertion grooves 24c and 25c at the corners provided with the recessed portions 28c. In this case, the outer magnetic pole portion 28 is pressed against the side surfaces 24d and 25d of the insertion grooves 24c and 25c on the radially outer side. On the inner side surface in the direction, the insertion grooves 24c and 25c are assembled with the side surfaces 24e and 25e and the gap S therebetween.

  As a result, the outer magnetic pole portion 28 has a portion other than both corners of the axial end portion inserted in the insertion grooves 24c and 25c exposed to the radially outer side (stator 2 side) from the openings 24g and 25g. It is possible to widen the magnetic flux generating surface that directly faces the magnetic flux, and to increase the effective magnetic flux. Moreover, since only the two corners (a part in the circumferential direction) at the axial end of the outer magnetic pole portion 28 are inserted into the insertion grooves 24c and 25c, the press-fitting load of the outer magnetic pole portion 28 is reduced, and the press-fitting is performed. Work becomes easy. Further, as shown in FIG. 4A, the outer magnetic pole portion 28 bulges to the outermost periphery of the rotor 20 except for both corners of the axial end portion inserted into the insertion grooves 24 c and 25 c. The effective magnetic flux can be increased by reducing the gap between the outer magnetic pole portion 28, that is, the magnet magnetic pole 26 and the stator 2 facing the outer magnetic pole portion 28.

  In the above embodiment, the insertion portions of the cover members 24 and 25 are the insertion grooves 24c and 25c that are recessed in the axial direction. However, the present invention is not limited to this, and for example, the insertion portions are formed as through holes penetrating in the axial direction. It may be configured. Further, the axial end portions of the outer magnetic pole portion 28 are inserted into the insertion portions of the cover members 24 and 25, but the projections are provided on the cover members 24 and 25, and the outer magnetic pole portion 28 is provided with a concave portion. May be reversed.

  In the above embodiment, the axial end of the outer magnetic pole portion 28 inserted into the insertion grooves 24c and 25c is slight, but for example, a part of the radially outer portions 24f and 25f outside the insertion grooves 24c and 25c or The entirety may be extended in the axial direction, and the flat surface 28b on the outer side of the outer magnetic pole portion 28 may be contacted in a wide range in the axial direction. In this case, in the press-fitting into the insertion grooves 24c and 25c at a limited portion at the axial end of the outer magnetic pole portion 28, the axial central portion tends to bend in the radial direction. By extending 25f in the axial direction, the curved shape is reduced.

  In the above embodiment, in the magnet magnetic pole 26, the inner and outer magnetic pole portions 27 and 28 are separated from each other in the circumferential direction of the permanent magnet 23. However, the present invention is not limited to this. From the viewpoint of reducing the leakage magnetic flux, it is preferable to separate the members from each other. However, for example, the inner and outer magnetic pole portions 27 and 28 may be in contact with each other. In this case, since the magnetic resistance is higher in the contact portion between the inner and outer magnetic pole portions 27 and 28 than in the case of the integral configuration, the generated leakage magnetic flux is small.

  In the above embodiment, the outer magnetic pole portion 28 is configured by laminating the substantially rectangular parallelepiped core member 29 in the circumferential direction. However, the present invention is not limited to this, and the configuration in which the core member 29 is laminated in the axial direction, The outer magnetic pole portion 28 may be configured by compression molding of magnetic powder. Further, the core body portion 21a of the rotor core 21 may also be configured by compression molding of magnetic powder.

  -In above-mentioned embodiment, although each cover member 24 and 25 was comprised in the substantially annular shape, it is not limited to this. For example, in the cover members 24 and 25, the magnet magnetic pole 26 portion may be left and the salient pole 31 portion may be omitted.

  In the above embodiment, the rotor core 21 is fitted and fixed to the rotary shaft 7 by the press-fitting hole 21b. However, the present invention is not limited to this. For example, if the rotor core 21 can be held by the cover members 24 and 25, the center hole of the rotor core 21 is formed. It may be formed larger than the outer diameter of the rotating shaft 7 so that the rotor core 21 and the rotating shaft 7 are not in contact with each other. Thereby, weight reduction of the rotor core 21 is achieved, and the leakage magnetic flux to the rotating shaft 7 is reduced.

The number of magnetic poles of the rotor 20 in the above embodiment is an example, and may be changed as appropriate.
In the above embodiment, the present invention is applied to the rotor 20 used in the inner rotor type motor M, but may be applied to the rotor of an outer rotor type motor. In this case, the opposing relationship in the radial direction between the rotor and the stator is reversed.
In each of the above embodiments, the present invention is applied to a half-magnet type IPM motor in which the magnet magnetic poles 26 and the salient poles 31 are alternately arranged in the circumferential direction of the rotor 20. The present invention may be applied to a full magnet type IPM motor constituted by H.26.

  2 ... stator, 6 ... winding magnetic pole (stator magnetic pole), 21 ... rotor core, 23 ... permanent magnet, 24, 25 ... cover member (holding member), 24b, 25b ... engaging portion, 24c, 25c ... insertion groove ( Insertion part), 24d, 25d ... side face (press-fit part), 24g, 25g ... opening part (opening part), 26 ... magnet magnetic pole, 27 ... inner magnetic pole part (counter stator side magnetic pole part), 28 ... outer magnetic pole part (stator) Side magnetic pole part), S ... gap.

Claims (7)

A magnet embedded rotor configured such that a plurality of magnet magnetic poles are formed in the circumferential direction of the rotor core so as to face the magnetic poles of the stator, and a permanent magnet is embedded in the magnet magnetic pole,
The magnet magnetic pole is formed integrally with the rotor core and is provided on the anti-stator side magnetic pole portion provided on the anti-stator side of the permanent magnet, and on the stator side of the permanent magnet to be able to open the housing portion for the permanent magnet. It is composed of a stator side magnetic pole portion that is separable from the anti-stator side magnetic pole portion,
The holding members provided on both axial sides of the rotor core hold the axial end portions of the stator side magnetic pole portions, respectively, and hold the permanent magnet with the stator side magnetic pole portions and the anti-stator side magnetic pole portions. A magnet-embedded rotor characterized by being configured as described above. The embedded magnet rotor according to claim 1,
The magnet-embedded rotor, wherein the holding member is provided with an insertion portion formed in an axial direction so as to insert and hold an axial end portion of the stator side magnetic pole portion. The embedded magnet rotor according to claim 2,
The insertion portion has a press-fit portion that press-contacts with a stator-side portion of the stator-side magnetic pole portion, and is configured such that a gap is formed between the stator-side magnetic pole portion and an anti-stator-side portion. Embedded magnet rotor. In the magnet-embedded rotor according to claim 2 or 3,
A part of the circumferential direction at the axial end portion of the stator side magnetic pole portion is inserted into the insertion portion,
The magnet-embedded rotor according to claim 1, wherein the holding member is provided with an opening portion that exposes a portion other than the stator side magnetic pole portion inserted to the stator side. The magnet-embedded rotor according to any one of claims 2 to 4,
The stator-side magnetic pole portion is provided with a magnet-embedded rotor in which a protruding portion that protrudes toward the stator side from a portion that is inserted into the insertion portion is provided on a side surface of the stator between the axial directions of the holding member. In the magnet-embedded rotor according to any one of claims 1 to 5,
An embedded magnet rotor, wherein at least one of holding members provided on both sides of the rotor core in the axial direction is provided with engaging portions that protrude in the axial direction and engage with both sides of the magnet magnetic pole in the circumferential direction.   A motor comprising the magnet-embedded rotor according to any one of claims 1 to 6.

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