JP2013027106A - Permanent magnet type motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively prevent generation of leakage flux from a permanent magnet 3 while preventing increase in the length in the rotor axial center direction of a permanent magnet type motor.SOLUTION: A plurality of recessed grooves 2b extending in the rotor axial center direction are formed on an outer peripheral face of a rotor core 2, leaving intervals in the circumferential direction. A permanent magnet 3, a pressing member 31 nipping the permanent magnet 3 within the recessed groove 2b together with a wall face portion 2c of the recessed groove 2b and a regulation member 32 fixed to the wall face portion 2c of the recessed groove 2b are arranged within each recessed groove 2b. The regulation member 32 is configured to support the pressing member 31 from the rotor radial outer side of the pressing member 31 located within the recessed groove 2b where the regulation member 32 is arranged and regulate movement of the pressing member 31 in cooperation with the wall face portion 2c of the recessed groove 2b.

Description

  The present invention belongs to a technical field related to a permanent magnet motor including a rotor having a rotor core provided with permanent magnets and a stator having windings disposed on the outer peripheral side of the rotor core of the rotor.

  Conventionally, a permanent magnet type motor (IPM motor) in which a permanent magnet is embedded in a rotor core is well known. In such a motor, there is a problem that leakage magnetic flux from the permanent magnet is generated between the end portion of the permanent magnet and the outer peripheral surface of the rotor core, thereby reducing the motor efficiency.

  Therefore, in order to prevent such leakage magnetic flux from occurring, for example, in Patent Document 1, a plurality of concave grooves extending in the axial direction of the rotor are formed on the outer circumferential surface of the rotor core at intervals in the circumferential direction. A permanent magnet is disposed in each concave groove portion, and the permanent magnet in each concave groove portion is sandwiched between a wall surface portion of the concave groove portion and a pressing member (a suppressing member in Patent Document 1), and the rotor of the rotor core It has been proposed to fix the permanent magnet and the pressing member by two end plates respectively disposed on both sides in the axial direction.

JP 2011-4519 A

  However, in the thing of the said patent document 1, the through-hole penetrated to a rotor axial direction is provided in the holding member, A bar is inserted in this through-hole, and this presser is used as an end plate through this bar. Because it is fixed, an end plate is required for fixing the presser member. For this reason, the length of the permanent magnet motor in the axial direction of the rotor increases and the cost increases by the thickness of the end plate. Will be invited. In particular, by laminating a plurality of rotor cores in the axial direction of the rotor and shifting the circumferential position of each groove in the plurality of rotor cores in the circumferential direction between the plurality of rotor cores, the cogging torque of the permanent magnet motor When trying to reduce the output torque fluctuation (torque ripple), the length of the permanent magnet motor in the axial direction of the rotor and the cost are further disadvantageous.

  The present invention has been made in view of such a point, and the object of the present invention is to reduce the cost of the permanent magnet motor from the permanent magnet at a low cost while preventing the length of the permanent magnet motor from extending in the axial direction of the rotor. The purpose is to prevent the occurrence of leakage magnetic flux.

  In order to achieve the above object, in the present invention, a permanent magnet type comprising a rotor having a rotor core provided with a permanent magnet and a stator having a winding disposed on the outer peripheral side of the rotor core of the rotor. For the motor, a plurality of concave grooves extending in the rotor axial direction are formed on the outer circumferential surface of the rotor core at intervals in the circumferential direction.In each concave groove, the permanent magnet and A pressing member that clamps the permanent magnet in the concave groove portion together with the wall surface portion of the concave groove portion, and a restriction member fixed to the wall surface portion of the concave groove portion, are provided, and the restriction member is The retainer is supported from the outside in the rotor radial direction of the retainer in the recessed groove where the restricting member is disposed, and is configured to restrict the movement of the retainer in cooperation with the wall surface of the recessed groove. It was configured as being.

  With the above configuration, since the permanent magnet is sandwiched together with the wall surface portion of the recessed groove portion by the pressing member separate from the rotor core, generation of leakage magnetic flux from the permanent magnet can be prevented. In addition, since a regulating member configured to regulate the movement of the presser member is disposed in each concave groove portion, it is fixed to the wall surface portion of the concave groove portion so as not to move the presser member via the regulating member. can do. Further, the restricting member supports the presser member from the outer side in the rotor radial direction of the presser member. Therefore, even when the presser member tries to move particularly outward in the rotor radial direction by the rotation of the rotor, the movement can be reliably restricted. . As a result, it is not necessary to arrange members for fixing the pressing member on both sides of the rotor core in the rotor axial direction. Therefore, the length of the permanent magnet motor in the axial direction of the rotor is not increased, and the cost can be reduced.

  In the permanent magnet motor, the rotor includes a plurality of the rotor cores in which the permanent magnets, the pressing member, and the regulating member are disposed in the concave grooves, and the plurality of rotor cores are arranged in a rotor axial direction. The circumferential positions of the concave grooves in the plurality of rotor cores are shifted in the circumferential direction between the plurality of rotor cores, and one of the two adjacent rotor cores adjacent to one another in the rotor axial direction. It is preferable that the circumferential position of each concave groove portion of the rotor core is shifted by a predetermined angle to one circumferential direction side with respect to each concave groove portion of the rotor core on the other side in the rotor axial direction.

  As a result, the cogging torque and output torque fluctuation (torque ripple) of the permanent magnet motor can be reduced. On the other hand, when laminating a plurality of rotor cores in the rotor axial direction as described above, assuming that members for fixing the pressing member are disposed on both sides of each rotor core in the rotor axial direction, the rotor of the permanent magnet motor This is further disadvantageous in terms of axial length and cost. Moreover, motor efficiency will fall because the member for fixing a pressing member interposes between adjacent rotor cores. However, in the present invention, it is not necessary to provide a member for fixing the pressing member on both sides of each rotor core in the axial direction of the rotor, so that the length of the permanent magnet motor in the axial direction of the rotor is made as long as possible. It is possible to prevent this from occurring, and it is possible to suppress the cost increase as much as possible. Moreover, the fall of the motor efficiency by providing the said member for fixing a pressing member can be suppressed.

  In the permanent magnet type motor, a plurality of permanent magnets in the concave groove portions are arranged in a state of being spaced from each other between the pressing member and the wall surface portion of the concave groove portion. It is preferable that a resin is filled between the plurality of permanent magnets between the wall surface of the concave groove.

  By doing so, the resin to be filled can eliminate the gap existing in the concave groove portion, thereby preventing rattling between the permanent magnet, the pressing member and the regulating member, The movement of the pressing member can be more reliably regulated.

  In the permanent magnet motor, a cover member is provided on the outer peripheral surface of the rotor core, in which the permanent magnet, the pressing member, and the regulating member are disposed in each concave groove, and covers the entire outer periphery. Is preferable.

  As a result, even if the pressing member attempts to move particularly outward in the radial direction of the rotor due to the rotation of the rotor, the movement can be more reliably restricted by the cover member. In addition, by configuring the cover member with a thin non-magnetic material and a conductor, it is possible to flow a high-frequency current generated in association with the switching action of the inverter to the cover member using the skin effect, Heat generation can be suppressed.

  As described above, according to the permanent magnet type motor of the present invention, the permanent magnet is clamped together with the wall surface of the recessed groove portion by the holding member separate from the rotor core, thereby preventing the generation of leakage magnetic flux from the permanent magnet. In addition, since the pressing member can be fixed to the wall surface portion of the groove portion so as not to move via the regulating member disposed in the groove portion, the rotor core can be fixed to both sides of the rotor core in the axial direction of the rotor core. Therefore, it is not necessary to provide a member for fixing the presser member. Therefore, the length of the permanent magnet motor in the axial direction of the rotor is not increased, and the leakage magnetic flux is generated from the permanent magnet at a low cost. Can be prevented.

It is a perspective view which shows a part of permanent magnet type motor which concerns on Embodiment 1 of this invention. It is a perspective view which shows the rotor part of the rotor of the said permanent magnet type motor. It is a disassembled perspective view which shows the rotor core of the said rotor part, a permanent magnet, the pressing member, and a control member. It is the figure seen from the rotor axial center direction which expands and shows the concave-groove part of the said rotor core. FIG. 5 is a view corresponding to FIG. 4 illustrating a state in which a permanent magnet, a pressing member, and a regulating member are disposed in the concave groove portion. FIG. 3 is a view corresponding to FIG. FIG. 9 is a view corresponding to FIG. FIG. 6 is a view corresponding to FIG. FIG. 9 is a view corresponding to FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a part of a permanent magnet motor M according to Embodiment 1 of the present invention. In this embodiment, the permanent magnet motor M is used as a motor for driving an electric vehicle or a hybrid vehicle, and has a rotor core 2 provided with a plurality of permanent magnets 3 made of rare earth magnets or the like. A rotor 1 and a stator 11 disposed coaxially on the outer peripheral side of the rotor core 2 of the rotor 1 are provided.

  A through hole 2a into which a rotation shaft (motor shaft) (not shown) is press-fitted is formed at the center (rotor axis) of the rotor core 2. The rotation shaft press-fitted into the through hole 2a and the rotor core 2 are connected to each other. Rotates integrally around the rotor axis. The rotor core 2 is formed by laminating a plurality of substantially ring-shaped electromagnetic steel plates in the rotor axial direction.

  In the present embodiment, the rotor core 2 is provided with a pressing member 31 and a regulating member 32 (to be described later) together with the permanent magnet 3, and all of these provided on the rotor core 2 are referred to as the rotor portion 4. To. The rotor 1 is constituted by the rotor portion 4 and the rotating shaft.

  The stator 11 has a stator core 12 formed by laminating a plurality of electromagnetic steel plates, and a winding 21 that is energized from a DC power source via an inverter in order to rotate the rotor 1. The stator core 12 is provided on a yoke portion 13 formed in a substantially annular shape and an inner peripheral surface of the yoke portion 13, and extends radially inward of the yoke portion 13 at equal intervals in the circumferential direction of the yoke portion 13. It has a plurality of teeth portions 14 to be taken out. The teeth portions 14 extend toward the central axis of the substantially annular yoke portion 13 (that is, the central axis of the stator core 12 (coincident with the rotor axis)). The extension lengths of the plurality of teeth portions 14 are the same. A slot portion 15 in which the winding 21 is accommodated is formed between adjacent teeth portions 14.

  The winding 21 is accommodated in the slot portion 15 so as to be wound around the tooth portion 14 by distributed winding. That is, the winding 21 (coil) is wound over two or more tooth portions 14 among all the tooth portions 14 of the stator core 12. Coil end portions 21 a arranged outside the slot portion 15 (on both sides in the central axis direction of the stator core 12 with respect to the slot portion 15) in all windings 21 of the stator 11 are on both sides in the central axis direction of the stator core 12 in all the tooth portions 14. In FIG. 1, a part of the coil end part 21a is omitted so that a part of the teeth part 14 can be seen.

  In the present embodiment, a substantially cylindrical case portion 16 is coaxially disposed on the outer peripheral side of the yoke portion 13. The case portion 16 is made of iron and used as a back yoke. The yoke portion 13 (stator core 12) is press-fitted into the inner peripheral portion of the case portion 16, and the outer peripheral surface of the yoke portion 13 and the inner peripheral surface of the case portion 16 are in close contact with each other.

  Here, a positioning key (not shown) extending in the direction of the central axis of the yoke portion 13 is formed so as to protrude at at least one location on the outer peripheral surface of the yoke portion 13 in the circumferential direction. On the other hand, a key groove (not shown) into which the positioning key is fitted is formed on the inner peripheral surface of the case portion 16. The yoke portion 13 and the case portion 16 are positioned in the circumferential direction by fitting the positioning key and the key groove. As a result, after the yoke portion 13 is press-fitted into the inner peripheral portion of the case portion 16, the yoke portion 13 does not rotate with respect to the case portion 16.

  In the present embodiment, the case portion 16 is a water-cooled case portion having a water jacket 17. The water jacket 17 has a plurality of axially extending portions 17 a that extend in the case portion cylinder axial direction and are provided at intervals in the circumferential direction. Opening is made only on one end face in the axial direction (end face on the near side in FIG. 1). These openings are closed by a substantially annular closing portion (not shown) provided on the end surface of the case portion 16 on one side in the cylinder axis direction. A flow path for connecting the plurality of axially extending portions 17a in series is provided at the end of the closing portion and the case portion 16 on the other side in the cylindrical axis direction, and thus the inside of the case portion 16 is provided. A water jacket 17 that makes about one turn is formed. A supply pipe and a discharge pipe (not shown) are connected to the water jacket 17, and cooling water is supplied to the water jacket 17 through the supply pipe, and the cooling water flows through the water jacket 17 to form a case portion. After about one round in 16, it is discharged through the discharge pipe. Although the water jacket 17 is not always necessary, it is preferable to provide the water jacket 17 in the case of the vehicle driving motor as in this embodiment.

  As shown in FIGS. 2 to 5, a plurality of (eight in this embodiment) concave groove portions 2 b extending in the axial direction of the rotor are formed on the outer peripheral surface of the rotor core 2 at equal intervals in the rotor circumferential direction. (See FIG. 3 and FIG. 4 in particular). Each groove 2b has a substantially trapezoidal shape when viewed from the rotor axial direction. The wall surface portion 2c of each concave groove portion 2b includes a first wall surface portion 2d located at the central portion of the wall surface portion 2c in the circumferential direction of the rotor and a rotor wall surface in both sides of the first wall surface portion 2d from the both sides in the rotor radial direction. The second and third wall surface portions 2e and 2f extend so as to widen the gap.

  Three permanent magnets 3 are disposed in each concave groove 2b. With these three permanent magnets 3 as a set, eight sets of permanent magnets 3 are provided on the rotor core 2, and thereby eight magnetic poles are formed in the rotor portion 4. The length of the permanent magnet 3 in the rotor axial direction is substantially the same as the length of the rotor core 2 in the rotor axial direction.

  Further, in each concave groove portion 2b, a pressing member 31 is provided which clamps the three permanent magnets 3 in the concave groove portion 2b together with the wall surface portion 2c of the concave groove portion 2b. The pressing member 31 also has a substantially trapezoidal shape when viewed from the rotor axial direction. The pressing member 31 includes first to third clamping surface portions 31a to 31c that face the first to third wall surface portions 2d to 2f of the concave groove portion 2b with a predetermined interval, respectively, and the first groove portion 2b has a first groove portion 2b. Between the wall surface portion 2d and the first clamping surface portion 31a of the pressing member 31, between the second wall surface portion 2e of the concave groove portion 2b and the second clamping surface portion 31b of the pressing member 31, and the third wall surface portion of the concave groove portion 2b. Between the 2 f and the third clamping surface portion 31 c of the pressing member 31, the three permanent magnets 3 are disposed and held in a state of being spaced apart from each other. Hereinafter, the permanent magnet 3 sandwiched between the first wall surface portion 2d and the first sandwiching surface portion 31a is referred to as a first permanent magnet 3a, and is sandwiched between the second wall surface portion 2e and the second sandwiching surface portion 31b. The permanent magnet 3 is referred to as a second permanent magnet 3b, and the permanent magnet 3 sandwiched between the third wall surface portion 2f and the third sandwiching surface portion 31c is referred to as a third permanent magnet 3c. However, when it is not necessary to distinguish these first to third permanent magnets 3a to 3b, they are simply referred to as permanent magnets 3.

  The pressing member 31 is formed by laminating a plurality of electromagnetic steel plates in the rotor axial direction. The electromagnetic steel plate of the pressing member 31 may be of the same grade as the electromagnetic steel plate of the rotor core 2, but is of a grade with excellent magnetic properties so that the iron loss is less than that of the electromagnetic steel plate of the rotor core 2 ( For example, it is preferable to employ a grade having a large silicon addition amount.

  As shown in FIGS. 3 to 5, the fitting recesses 2 g that are slightly recessed are respectively formed in the portions where the first to third permanent magnets 3 a to 3 b abut on the first to third wall surface portions 2 d to 2 f, respectively. The end of the first to third permanent magnets 3a to 3b on the wall surface 2c side is fitted to each fitting recess 2g. Further, on the outer side in the rotor radial direction of the fitting recess 2g in the second and third wall surface portions 2e, 2f, a groove portion 2h extending in the rotor axial direction is formed respectively, and the second and third wall surface portions 2e, 2f Protruding portions 2i that protrude in the rotor circumferential direction are formed on the outer side in the rotor radial direction of the groove portion 2h. These protrusions 2i protrude toward the sides close to each other so that the opening on the outer side in the rotor radial direction of the groove 2b is narrowed.

  Further, a regulating member 32 made of nonmagnetic resin is disposed in each concave groove 2b. The resin material of the regulating member 32 is preferably a heat-resistant material such as PPS (polyphenylene sulfide).

  As shown in FIGS. 3 and 4, the regulating member 32 has a substantially trapezoidal frame-like portion 32 a when viewed from the rotor axial direction. The frame-like portion 32a has substantially the same shape and size as the concave groove portion 2b when viewed from the rotor axial direction, and is inserted into and fitted in the concave groove portion 2b from the rotor axial direction. It has become. When the frame-shaped portion 32a is fitted into the groove portion 2b, the four corner portions of the frame-shaped portion 32a abut against the wall surface portion 2c of the groove portion 2b. That is, two corners on the inner side in the rotor radial direction after the four corners of the frame-like portion 32a are the portions between the fitting recess 2g of the first wall surface portion 2d and the fitting recess 2g of the second wall surface portion 2e, and Two corners on the outer side in the rotor radial direction are in contact with the protrusions 2i, respectively, in contact with portions between the fitting recess 2g of the first wall surface portion 2d and the fitting recess 2g of the third wall surface portion 2f. . In the completed state of the rotor part 4, the frame-like part 32a protrudes outside the concave groove part 2b.

  First to fourth support portions 32b to 32e extending to one side in the rotor axial direction are provided on surfaces on one side in the rotor axial direction at the four corners of the frame-shaped portion 32a. Among the first to fourth support parts 32b to 32e, the ones located on the outer side in the rotor radial direction are the first and second support parts 32b and 32c, and the ones located on the inner side in the rotor radial direction are the third and fourth support parts. 32d and 32e. The lengths of the first to fourth support portions 32b to 32e are substantially the same as the length of the rotor core 2 in the rotor axial direction, but a stopper portion 32f described later provided at the tip of each support portion 32b to 32e, respectively. Therefore, the length of the rotor core 2 is slightly longer than the length of the rotor core 2 in the axial direction of the rotor.

  The frame-shaped part 32a supports the pressing member 31 and the three permanent magnets 3 before the restricting member 32 is inserted into the recessed groove part 2b, and the restricting member 32 is supported with respect to the recessed groove part 2b in this supported state. This is provided for facilitating insertion from one side in the rotor axial direction, and is not basically required when the rotor portion 4 is completed. Each of the stopper portions 32f, which will be described later, is in contact with the surface of the rotor core 2 on one side in the axial direction of the rotor core 2 when insertion of the supporting member 32 is completed, and prevents the restricting member 32 from being inserted further. The stopper portions 32f are basically not necessary when the rotor portion 4 is completed. In the completed state of the rotor part 4, the first to fourth support parts 32b to 32e excluding the stopper part 32f, the three permanent magnets 3 and the pressing member 31 are arranged in the concave groove part 2b.

  On the surface of the first and second support portions 32b and 32c opposite to the surfaces facing each other in the circumferential direction of the rotor, a protrusion 32g fitted into the groove 2h extends over the entire rotor axial direction. Each of the protrusions 32g extends continuously to the frame-like portion 32a. The first and second support portions 32b and 32c are in contact with the protruding portions 2i in the same manner as the two corner portions on the outer side in the rotor radial direction of the frame-shaped portion 32a. As a result, the first and second support portions 32b and 32c cannot be deformed to the side where the distance between the support portions 32b and 32c in the circumferential direction of the rotor is increased or to the outside in the rotor radial direction. The radius of the outer surface in the rotor radial direction of the first and second support portions 32b and 32c and the frame-like portion 32a is the same as the radius of the outer peripheral surface of the rotor core 2, and the first and second support portions 32b and 32c and the frame The outer surface in the rotor radial direction of the shaped portion 32a and the outer peripheral surface of the rotor core 2 are located on the same circumference when viewed from the rotor axial direction. At the tips of the first and second support portions 32b and 32c, stopper portions 32f are formed that protrude to the side where both the support portions 32b and 32c are separated in the circumferential direction of the rotor.

  The third support portion 32d is positioned between the first and second permanent magnets 3a and 3b, and has two standing wall portions 32h that are substantially V-shaped when viewed from the rotor axial direction. Surfaces of the two standing wall portions 32h on the wall surface portion 2c side are in contact with the first and second wall surface portions 2d and 2e, respectively. The opposite surfaces of the two standing wall portions 32h are in contact with the first and second permanent magnets 3a and 3b, respectively. A stopper portion 32f that protrudes inward in the rotor radial direction is formed at the tip of the two standing wall portions 32h of the third support portion 32d.

  Further, the fourth support portion 32e is located between the first and third permanent magnets 3a and 3c and, like the third support portion 32d, has two V-shapes when viewed from the rotor axial direction. It has the standing wall part 32i. The surface of the two standing wall portions 32i on the wall surface portion 2c side is in contact with the first and third wall surface portions 2d and 2f, respectively. The opposite surfaces of the two standing wall portions 32i are in contact with the first and third permanent magnets 3a and 3c, respectively. Stopper portions 32f that protrude inward in the rotor radial direction are also formed at the tips of the two standing wall portions 32i in the fourth support portion 32e.

  The pressing member 31 is supported between the first to fourth support portions 32b to 32e. In other words, the first to fourth support portions 32 b to 32 e abut on the four corner portions of the presser member 31 viewed from the rotor axial direction, and the first to fourth support portions 32 b to 32 e sandwich the presser member 31. I support it. As shown in FIG. 5, the two corners on the outer side in the rotor radial direction of the presser member 31 as viewed from the rotor axial direction are rounded with a chamfer having a relatively large radius. The surfaces of the first and second support portions 32 b and 32 c that are opposed to each other in the rotor circumferential direction also have a shape corresponding to the corner portion, and the first and second support portions 32 b and 32 c are the rotors of the pressing member 31. It will wrap around radially outward. Thus, the first and second support portions 32b and 32c of the regulating member 32 support the holding member 31 from the outer side in the rotor radial direction of the holding member 31 in the recessed groove portion 2b in which the regulating member 32 is disposed. become. Two corners on the inner side in the rotor radial direction of the pressing member 31 are in contact with the inner surfaces in the rotor radial direction on the third and fourth support portions 32d and 32e. Note that the outer surface of the pressing member 31 in the rotor radial direction (excluding the two corners supported by the first and second support portions 32b and 32c) is viewed from the outer peripheral surface of the rotor core 2 and the rotor axial direction. Located on the same circumference.

  Although not shown, between the two standing wall portions 32h of the third support portion 32d and between the two standing wall portions 32i of the fourth support portion 32e, that is, the pressing member 31 and the wall surface portion 2c of the groove portion 2b A resin is filled between the three permanent magnets 3. This resin is obtained by curing a liquid material after filling. As such a resin, for example, a one-component adhesive such as a one-component epoxy resin composition adhesive is preferable. The resin is filled after the regulating member 32 is inserted into the concave groove portion 2b in a state where the pressing member 31 and the three permanent magnets 3 are supported, and is eventually cured.

  The regulation member 32 is fixed to the wall surface portion 2c of the concave groove portion 2b by filling the resin. Further, the two standing wall portions 32h of the third support portion 32d are pressed by the resin so that the interval between the compatible wall portions 32h is widened, and thereby the first permanent magnet 3a is pressed toward the fourth support portion 32e. At the same time, the second permanent magnet 3b is pressed toward the first support portion 32b. Furthermore, the two standing wall portions 32i of the fourth support portion 32e are pressed by the resin so that the interval between the compatible wall portions 32i is widened, and thereby the first permanent magnet 3a is pressed toward the third support portion 32d. At the same time, the third permanent magnet 3b is pressed toward the second support portion 32c. Accordingly, the first permanent magnet 3a is fixed between the third and fourth support portions 32d and 32e. In addition, the first and second support portions 32b and 32c are in contact with the protruding portion 2i, and the protruding portion 32g is fitted in the groove portion 2h. Therefore, the second permanent magnet 3b The third permanent magnet 3c is fixed between the second and fourth support portions 32c and 32e, and is fixed between the third support portions 32b and 32d.

  Moreover, the 3rd and 4th support parts 32d and 32e are pressed to the rotor radial direction outer side by filling of the said resin. Thereby, although the pressing member 31 is pressed outward in the rotor radial direction, the pressing member 31 cannot move outward in the rotor radial direction by the first and second support portions 32b and 32c. In this state, the pressing member 31 presses the first to third permanent magnets 3a to 3c against the first to third wall surface portions 2d to 2f by the first to third clamping surface portions 31a to 31c, respectively. Yes.

  Furthermore, by filling the resin, there is no gap in the recessed groove portion 2b, and rattling between the permanent magnet 3, the pressing member 31, and the regulating member 32 is eliminated. As a result, the permanent magnet 3 and the pressing member 31 cannot move in any direction within a plane perpendicular to the rotor axial direction, and the wall surface portion 2c of the recessed groove portion 2b, the permanent magnet 3, the pressing member 31, and Since the regulating member 32 (the first to fourth support portions 32b to 32e) is pressed against each other, the permanent magnet 3 and the pressing member 31 cannot move in the rotor axial direction. In this way, the regulating member 32 regulates the movement of the pressing member 31 in cooperation with the wall surface portion 2c of the concave groove portion 2b.

  In order to manufacture the rotor 1, first, the rotating shaft (motor shaft), the rotor core 2, the permanent magnet 3, the pressing member 31 and the regulating member 32 are separately manufactured.

  Subsequently, the pressing member 31 is inserted between the first to fourth support portions 32b to 32e of the restricting member 32 from the opposite side of the frame-shaped portion 32a, and the first between the third and fourth support portions 32d and 32e. The permanent magnet 3a is inserted between the first and third support portions 32b and 32d, and the third permanent magnet 3c is inserted between the second and fourth support portions 32c and 32e.

  Next, the regulating member 32 is inserted into the concave groove portion 2 b of the rotor core 2 from one side in the rotor axial direction while supporting the pressing member 31 and the three permanent magnets 3. At this time, the regulating member 32 is moved so that the frame-like portion 32a is on the front side. When the stopper portions 32f of the first to fourth support portions 32b to 32e come into contact with the surface on one side in the rotor axial direction, the insertion of the regulating member 32 is completed. Then, the restriction member 32 is inserted into all the recessed groove portions 2 b of the rotor core 2.

  Thereafter, the resin is filled between the two standing wall portions 32h of the third support portion 32d and between the two standing wall portions 32i of the fourth support portion 32e in each concave groove portion 2b, and the resin is cured. Thus, the rotor unit 4 is completed. The resin filling may be performed every time the regulating member 32 is inserted into one concave groove 2b.

  Finally, the rotary shaft is press-fitted into the through hole 2a of the rotor core 2 of the rotor part 4 to complete the rotor 1. In addition, before inserting the said limitation member 32 in the ditch | groove part 2b of the rotor core 2, you may press-fit a rotating shaft in the through-hole 2a of the rotor core 2 previously.

  Therefore, in the present embodiment, since the permanent magnet 3 is sandwiched together with the wall surface portion 2c of the recessed groove portion 2b by the pressing member 31 separate from the rotor core 2, the generation of leakage magnetic flux from the permanent magnet 3 can be prevented. . In addition, a regulating member 32 is disposed in the recessed groove portion 2 b, and the regulating member 32 supports the holding member 31 from the outer side in the rotor radial direction of the holding member 31 and cooperates with the wall surface portion 2 c of the recessed groove portion 2. Then, since the movement of the pressing member 31 is restricted, it is not necessary to provide members for fixing the pressing member 31 on both sides of the rotor core 2 in the rotor axial direction. As a result, the length of the permanent magnet motor M in the rotor axial direction does not have to be increased, and the cost can be reduced.

(Embodiment 2)
FIG. 6 shows a second embodiment of the present invention. In the rotor 1, a plurality of rotor portions 4 (rotor cores 2) similar to those in the first embodiment are provided (two in FIG. 6).

  That is, in this embodiment, a rotating shaft (motor shaft) (not shown) is press-fitted so as to continuously pass through the through-holes 2a of the plurality of rotor cores 2, and is permanently inserted into the concave grooves 2b on the rotating shaft. A plurality of rotor cores 2 (rotor portions 4) provided with the magnet 3, the pressing member 31, and the regulating member 32 are stacked in the rotor axial direction. In FIG. 6, the two rotor parts 4 are stacked so that the frame-like parts 32 a of the regulating member 32 face each other, but the orientation of the rotor axial direction of each rotor part 4 is not limited to this, You may make it face the same direction.

  In the rotor portion 4 of the first embodiment, since the frame-shaped portion 32a and the stopper portion 32f of the regulating member 32 protrude from the concave groove portion 2b, the plurality of rotor cores 2 have at least one of the frame-shaped portion 32a and the stopper portion 32f. Will be stacked. However, the strength of the frame-shaped portion 32a and the stopper portion 32f is lower than that of the member for fixing the presser member 31 provided on both sides of the rotor core 2 in the axial direction of the rotor. It may be smaller than the thickness of the member for fixing the member 31. Further, if the frame-shaped portion 32a and the stopper portion 32f are eliminated, the plurality of rotor cores 2 come into direct contact with each other.

  The circumferential positions of the concave groove portions 2b in the plurality of rotor cores 2 are shifted from each other in the circumferential direction between the plurality of rotor cores 2. And the position of the circumferential direction of each concave groove part 2b of the rotor core 2 of the rotor axial direction one side among the arbitrary two rotor cores 2 adjacent to each other is relative to each concave groove part 2b of the rotor core 2 on the other side in the rotor axial direction. Therefore, it is shifted by a predetermined angle to one side in the circumferential direction. That is, a rotor core in which the circumferential position of each concave groove portion 2b of all the rotor cores 2 excluding the rotor core 2 located at one end in the rotor axial direction among the plurality of rotor cores 2 is located at one end in the rotor axial direction. 2 is shifted to the same side in the circumferential direction, and the shift amount of each concave groove 2b of the n-th (n is a natural number of 2 or more) rotor core 2 from the end on one side in the rotor axial direction is the predetermined angle. (N-1) times. The predetermined angle is set to an angle at which the cogging torque and output torque fluctuation (torque ripple) of the permanent magnet motor M can be reduced. The upper limit value of the predetermined angle is a concave groove portion in the case of m rotor cores 2. It is 1 / (m−1) of a pitch angle of 2b (45 ° in the case of eight concave groove portions 2b).

  In order to manufacture the rotor 1, the rotor unit 4 is manufactured in the same manner as in the first embodiment, and a plurality of rotor units 4 are prepared. In this embodiment, although not shown, a positioning key is provided on the rotating shaft so that the rotating shaft and the through hole 2a of the rotor core 2 can be positioned in the circumferential direction. Is provided with a keyway into which the positioning key is fitted. The position of the key groove in the circumferential direction is slid between the plurality of rotor portions 4.

  The plurality of rotor portions 4 are set so as to be stacked on each other while being sequentially positioned on the rotation axis in the circumferential direction. Thus, the circumferential positions of the concave groove portions 2b in the rotor core 2 of the plurality of rotor portions 4 set on the rotation shaft are shifted in the circumferential direction between the plurality of rotor cores 2.

  In the case of the two rotor portions 4, the two rotor cores 2 before the restriction member 32 is inserted into the concave groove portion 2 b are set on the rotating shaft, and then the pressing member 31 is inserted into the concave groove portions 2 b of both rotor cores 2. And it is possible to insert the regulating member 32 in a state where the three permanent magnets 3 are supported. In such a case, the two rotor parts 4 are laminated so that the frame-like parts 32a of the regulating member 32 face each other.

  Therefore, in this embodiment, the cogging torque and output torque fluctuation of the permanent magnet motor M can be reduced. On the other hand, even if a plurality of motor parts 4 (rotor cores 2) are stacked in the rotor axial direction, there are no members for fixing the pressing members 31 on both sides of each rotor core 2 in the rotor axial direction. The length of the magnet motor M in the axial direction of the rotor can be prevented from becoming as long as possible, and the cost increase can be suppressed as much as possible. Moreover, the fall of the motor efficiency by providing the said member for fixing the pressing member 31 can be suppressed.

(Embodiment 3)
7 and 8 show the third embodiment of the present invention, in which the shape of the pressing member 31 and the regulating member 32 is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. This is the same as the rotor part 4 of the rotor 1.

  That is, in the present embodiment, stepped portions 31d that are recessed inwardly in the rotor radial direction with respect to the central portion in the rotor circumferential direction are formed on both ends in the rotor circumferential direction on the outer surface of the presser member 31 in the radial direction of the rotor. Yes. The first and second support portions 32b and 32c of the restricting member 32 are respectively positioned outside the stepped portions 31d in the rotor radial direction to support the pressing member 31.

  The width of each step 31d (the length in the circumferential direction of the rotor) is increased from one side to the other side in the rotor axial direction, whereby the distance between both stepped portions 31d, that is, The length in the rotor circumferential direction of the portion where the stepped portion 31d is not present on the outer surface in the rotor radial direction of the pressing member 31 is narrowed from one side to the other side in the rotor axial direction. Corresponding to the stepped portion 31d, the distance between the first and second support portions 32b and 32c is also narrowed from one side to the other side in the rotor axial direction. As a result, the length in the rotor circumferential direction of the portion not covered by the first and second support portions 32b and 32c on the outer surface in the rotor radial direction of the pressing member 31 is changed from one side to the other side in the rotor axial direction. It is getting smaller.

  With such a configuration, the cogging torque and output torque fluctuation of the permanent magnet motor M can be reduced as in the second embodiment. That is, in this embodiment, the cogging torque and output torque fluctuation of the permanent magnet motor M can be reduced without stacking the plurality of rotor portions 4 (rotor cores 2) as in the second embodiment. Therefore, the same effects as those of the second embodiment can be obtained at a lower cost while further reducing the length of the permanent magnet motor M in the axial direction of the rotor.

(Embodiment 4)
FIG. 9 shows Embodiment 4 of the present invention, and a cover that covers the entire circumference of the outer peripheral surface of the rotor core 2 in which the permanent magnet 3, the pressing member 31, and the regulating member 32 are disposed in each concave groove 2b. The member 35 is provided, and other configurations are the same as those of the rotor portion 4 of the rotor 1 of the first embodiment.

  The cover member 35 is preferably made of a nonmagnetic material and a conductor (for example, aluminum). Further, the thickness of the cover member 35 is set to a predetermined value or less, and is sufficiently thin so that it is not necessary to widen the distance between the outer peripheral surface of the rotor core 2 and the tip end surface of the teeth portion 14 of the stator core 12 ( For example, about 0.2 mm to 0.3 mm).

  If the cover member 35 is formed of a thin non-magnetic material and a conductor in this way, the skin effect can be used to flow a high-frequency current generated particularly with the switching action of the inverter to the cover member 35. Heat generation of the rotor core 2 can be suppressed. Even if the presser member 31 tries to move particularly outward in the rotor radial direction by the rotation of the rotor 1, the movement can be more reliably restricted by the cover member 35.

  The present invention is not limited to the embodiment described above, and can be substituted without departing from the spirit of the claims.

  For example, in the above-described embodiment, the number of permanent magnets 3 provided in each concave groove portion 2b is three. However, the number of permanent magnets 3 is not limited to this. For example, two permanent magnets 3 are arranged in the rotor axial direction. As seen, the gaps may be arranged in a substantially V shape that increases in width toward the outer side in the rotor radial direction. In this case, corresponding to the arrangement of the permanent magnet 3, the wall surface portion 2c of each concave groove portion 2b is substantially V-shaped when viewed from the rotor axial direction, and the pressing member 31 is approximately triangular when viewed from the rotor axial direction. The restriction member 32 may be configured to support the three corners of the pressing member 31.

  Moreover, in the said embodiment, although the regulating member 32 has the frame-shaped part 32a and the stopper part 32f, you may comprise the regulating member 32 only with the some support part in which the stopper part 32f is not formed. . In particular, in the case of the second embodiment, such a configuration is preferable. In this case, the permanent magnet 3 and the pressing member 31 may be inserted between the support portions after the support portions are inserted into the concave groove portions 2b and fixed to the wall surface portion 2c with an adhesive or the like. In addition, it is not always necessary to fill the resin. For example, the permanent magnet 3 and the pressing member 31 can be fixed in each concave groove 2b by using press-fitting, adhesion, or the like.

  The above-described embodiments are merely examples, and the scope of the present invention should not be interpreted in a limited manner. The scope of the present invention is defined by the scope of the claims, and all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  The present invention is useful for a permanent magnet motor including a rotor having a rotor core provided with permanent magnets and a stator having windings disposed on the outer peripheral side of the rotor core of the rotor. This is useful when a magnetic motor is used as a vehicle driving motor for an electric vehicle or a hybrid vehicle.

M Permanent Magnet Motor 1 Rotor 2 Rotor Core 2b Concave Groove 2c Wall Surface 3 Permanent Magnet 11 Stator 21 Winding 31 Pressing Member 32 Restricting Member 35 Cover Member

Claims (4)

A permanent magnet motor comprising a rotor having a rotor core provided with a permanent magnet, and a stator having a winding disposed on the outer peripheral side of the rotor core of the rotor,
On the outer peripheral surface of the rotor core, a plurality of concave grooves extending in the rotor axial direction are formed at intervals in the circumferential direction,
In each of the concave grooves,
The permanent magnet;
A pressing member for holding the permanent magnet in the concave groove part together with the wall surface part of the concave groove part;
A regulating member fixed to the wall surface of the concave groove,
Is arranged,
The restricting member supports the retainer member from the outer side in the rotor radial direction of the retainer member in the recessed groove portion where the restrictor member is disposed, and moves the retainer member in cooperation with the wall surface portion of the recessed groove portion. A permanent magnet motor characterized in that the motor is configured to regulate the motor. The permanent magnet motor according to claim 1,
The rotor has a plurality of the rotor cores in which the permanent magnets, the pressing member, and the regulating member are disposed in the concave grooves.
The plurality of rotor cores are stacked in the rotor axial direction,
The circumferential position of each concave groove in the plurality of rotor cores is shifted in the circumferential direction between the plurality of rotor cores,
Of any two adjacent rotor cores, the circumferential position of each concave groove portion of the rotor core on one side in the rotor axial direction is predetermined on one circumferential side with respect to each concave groove portion of the rotor core on the other side in the rotor axial direction A permanent magnet motor characterized by being shifted by an angle. The permanent magnet motor according to claim 1 or 2,
A plurality of permanent magnets in each of the concave groove portions are disposed in a state of being spaced apart from each other between the pressing member and the wall surface portion of the concave groove portion,
A permanent magnet motor, wherein a resin is filled between the plurality of permanent magnets between the pressing member and the wall surface of the concave groove. The permanent magnet motor according to any one of claims 1 to 3,
A permanent magnet, wherein a cover member is provided on the outer peripheral surface of the rotor core, in which the permanent magnet, the pressing member, and the regulating member are disposed in each of the concave grooves. Motor.

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