JP2017005916A - Manufacturing method of embedded magnet type rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an embedded magnet type rotor capable of securing an orientation rate and a magnetization rate of a field permanent magnet.SOLUTION: A permanent magnet 13 that is a bond magnet is oriented and magnetized outsides, thereby improving the orientation rate and the magnetization rate of the permanent magnet 13. When manufacturing an U-shaped permanent magnet 13, for example, first of all, a tabular molding 13b is manufactured from a magnet material 13a. Since the molding 13b is tabular, an even magnetic field can be applied over all the molding 13b uniformly. After the magnetization of the molding 13b is completed, the tabular molding 13b is deformed into U shape. Therefore, the orientation rate and the magnetization rate of the permanent magnet 13 are improved regardless of a shape and a portion of a rotor core 12 or the permanent magnet 13.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for manufacturing an embedded magnet type rotor.

  2. Description of the Related Art Conventionally, an embedded magnet type motor in which a permanent magnet serving as a field source is embedded in a rotor is known. An example of a method for manufacturing a rotor used in this motor is as follows. For example, as described in Patent Document 1, a cylindrical rotor core having a plurality of magnet holes is prepared, and after magnet materials are embedded in the magnet holes, a magnetizing device is arranged so as to cover the outer periphery of the rotor. The magnet material is magnetized by the magnetic flux generated from the magnetizing device passing through the magnet material.

  There are also embedded magnet type rotors in which bonded magnets are used as permanent magnets. For example, as described in Patent Document 2, the rotor core is provided with a plurality of U-shaped magnet holes that open toward the outer periphery side by side in the circumferential direction. These magnet holes are filled by injecting molten magnet material. After the filled magnet material is cooled and solidified, the magnet material is magnetized by the magnetic flux supplied from the outside of the rotor passing through the magnet material.

Japanese Patent Application Laid-Open No. 2010-193587 JP 2014-241705 A

  When magnetizing a magnet material embedded in the rotor core, the following may be a concern. That is, when a permanent magnet having a portion extending from the central portion of the rotor core toward the outer periphery, such as a permanent magnet having a U-shaped or V-shaped cross section perpendicular to the axis of the rotor core, is employed, the center of the rotor core in the permanent magnet The closer to the part, the harder the magnetic flux from the outside reaches.

  As shown in FIG. 12, the case where the magnet material 103 embedded in the U-shaped magnet hole 102 in the rotor core 101 is magnetized will be considered. In this case, the amount of the magnetic flux φ that passes through the U-shaped bottom portion 103a, which is the portion closest to the central portion of the rotor core 101 in the magnet material 103, is two from each end of the U-shaped bottom portion 103a toward the outer peripheral surface of the rotor core 101. This is less than the amount of magnetic flux φ passing through the U-shaped arm portions 103b and 103b. For this reason, the U-shaped magnet material 103 may have a portion that is not sufficiently oriented and magnetized.

  If the orientation rate and magnetization rate of the permanent magnet (magnet material 103) are not ensured due to insufficient magnetic flux φ supplied to the rotor, sufficient magnetic flux is not generated from the permanent magnet. The magnetic flux density at is also insufficient. In this case, the amount of effective magnetic flux interlinking with the stator coil of the motor is also insufficient, which contributes to a reduction in the output torque of the motor.

  An object of the present invention is to provide a method of manufacturing an embedded magnet type rotor that can ensure the orientation rate and the magnetization rate of a field permanent magnet.

  A manufacturing method of an embedded magnet type rotor capable of achieving the above object includes a cylindrical core and a resin-bonded bonded magnet embedded in a plurality of magnet holes provided in the core, and the shaft of the core When viewed from the direction, the magnet hole is a method for manufacturing an embedded magnet type rotor having a portion extending from the center of the core toward the peripheral surface. The manufacturing method includes a molded product obtained by molding a magnet material of the melted bonded magnet, the orientation magnetizing step of orienting and magnetizing the molded product before solidification outside the core, and the orientation magnetization Inserting the bonded magnet before solidification obtained through the magnetic process into the magnet hole.

  According to this manufacturing method, a molded product formed by molding a molten magnet material is oriented and magnetized before being inserted into the core, thereby magnetizing the molded product without being affected by the magnetic saturation of the core surface portion. It becomes possible to do. Unlike the case where a magnetizing magnetic field is applied from the outer periphery of the core in a state where the magnet material before magnetization or a molded product thereof is inserted into the magnet hole, the size of the magnetizer, for example, a magnetic field generation source ( The installation space of the magnetized magnet or magnetized coil is not limited by the number of magnetic poles of the rotor. For this reason, it is possible to use a magnetic field generating source that is larger in size and generates a stronger magnetic field. This makes it possible to apply a magnetic field having the required strength to the entire molded product. Therefore, the orientation rate and magnetization rate of the bonded magnet are increased. Uneven magnetization of the bond magnet and variations in magnetic characteristics as a permanent magnet are also suppressed.

  In the manufacturing method of the embedded magnet type rotor described above, when it is assumed that the magnet hole includes a curved portion intersecting with the radial direction of the core when viewed from the axial direction of the core, the orientation magnetization step Is a step performed prior to the forming step of forming the molten magnet material into a flat molded product, and the step performed between the orientation magnetization step and the insertion step, wherein the orientation It is preferable to include a deforming step of deforming the flat bonded magnet obtained through the magnetizing step into a shape corresponding to the shape of the magnet hole before solidifying the magnet.

  According to this manufacturing method, the flat molded product is magnetized and then deformed into a shape corresponding to the magnet hole. Unlike a case where a flat molded product is magnetized after being deformed into a shape corresponding to a magnet hole having a curved portion, it is easy to apply a magnetic field to the molded product.

In the above-described method for manufacturing an embedded magnet rotor, it is preferable that a magnetizing magnetic field is applied in a direction along a thickness direction of the flat plate-shaped molded product in the orientation magnetization step.
According to this manufacturing method, a uniform magnetic field can be uniformly applied to the entire flat molded product. For this reason, the orientation rate and the magnetization rate of the field permanent magnet can be improved.

  In the method for manufacturing an embedded magnet type rotor described above, in the insertion step, the bond magnet deformed into a shape corresponding to the shape of the magnet hole through the deformation step is a direction along the axial direction of the core. May be press-fitted into the magnet hole.

According to this manufacturing method, since the bonded magnet is press-fitted into the magnet hole, it is difficult to form a gap between the bonded magnet and the magnet hole.
In the method for manufacturing an embedded magnet type rotor described above, the thickness of the flat bonded magnet obtained through the orientation and magnetization step is a step performed between the orientation and magnetization step and the deformation step. You may include the compression process which makes the thickness of the said flat bond magnet thinner than the thickness of the said magnet hole by compressing to a direction.

According to this manufacturing method, since the thickness of the bonded magnet before solidification is thinner than the thickness of the magnet hole, it is easy to insert the bonded magnet into the magnet hole.
In the manufacturing method of the embedded magnet type rotor described above, a deformation return step of filling a gap between the bond magnet before solidification inserted into the magnet hole through the insertion step and an inner wall surface of the magnet hole is provided. Is preferred.

  According to this manufacturing method, loss of magnetic flux generated from the permanent magnet is reduced by closing the gap serving as the magnetic resistance. For this reason, the magnetic flux emitted from a permanent magnet can be used effectively.

  In the method of manufacturing an embedded magnet type rotor described above, the deformation return step utilizes a phenomenon in which the bond magnet before solidification that is elastically deformed in the deformation step or the compression step attempts to return to the original shape before elastic deformation. Thus, a gap between the bonded magnet and the inner wall surface of the magnet hole may be narrowed.

According to this manufacturing method, it is only necessary to wait for the gap between the bonded magnet and the magnet hole to be naturally clogged.
In the method of manufacturing an embedded magnet type rotor described above, in the deformation return step, an external force in a direction intersecting with the magnetization direction is positively applied to the bond magnet before solidification inserted into the magnet hole. The gap between the bonded magnet and the inner wall surface of the magnet hole may be narrowed by deforming it.

According to this manufacturing method, by applying an external force and positively deforming the bonded magnet, it is possible to suitably close the gap between the bonded magnet and the magnet hole.
In the manufacturing method of the embedded magnet type rotor described above, when it is assumed that the magnet hole is provided in a U-shape and two bonded magnets are inserted into one magnet hole, the deformation return step Then, by driving a wedge between the two bonded magnets inserted into one of the magnet holes, as viewed from the axial direction of the core, in the thickness direction of the bonded magnet, which is also the magnetization direction of the bonded magnet You may make it apply the external force which turned to the direction which cross | intersects to the said bond magnet.

  According to this manufacturing method, when viewed from the axial direction of the core, by applying an external force to the bond magnet in a direction intersecting with the thickness direction (magnetization direction) of the bond magnet, the two bond magnets have their thicknesses. Deforms in the direction. Thereby, the clearance gap between a bonded magnet and the inner wall face of a magnet hole can be closed suitably.

  In the manufacturing method of the embedded magnet type rotor described above, when it is assumed that the molded product is formed longer than the axial length of the core, in the deformation return step, the bond magnet inserted into the magnet hole By applying an external force in a direction along the axial direction of the core as a direction intersecting with the magnetization direction, the bond magnet is deformed toward the thickness direction which is also the magnetization direction. And a gap between the magnet hole and the inner wall surface of the magnet hole.

  According to this manufacturing method, the bonded magnet is deformed so as to escape in the thickness direction as much as it is compressed along the axial direction. For this reason, the clearance gap between a bonded magnet and the inner wall face of a magnet hole can be closed suitably.

  In the method of manufacturing an embedded magnet type rotor described above, the core is a step performed after the insertion step when it is premised that a plurality of electromagnetic steel plates are laminated, and before the core is solidified. A skew forming step of providing a skew by twisting the core in which the bonded magnet is inserted.

  According to this configuration, when a gap exists between the bond magnet and the inner wall surface of the magnet hole, the gap between the bond magnet and the inner wall surface of the magnet hole is reduced by deforming the core so as to be twisted. .

  In the above-described method for manufacturing an embedded magnet rotor, the core has an insertion hole through which a shaft passes, and a groove provided on an inner peripheral surface of the insertion hole and extending over the entire length in the axial direction of the core; In addition, in the skew forming step, the shaft is inserted into the insertion hole on the premise that a gentle spiral protrusion that engages with the groove is provided on the outer peripheral surface of the shaft inserted into the insertion hole. You may make it provide a skew by inserting in.

  According to this manufacturing method, as the shaft is inserted into the insertion hole, a large number of electromagnetic steel sheets constituting the core sequentially move in the circumferential direction following the gentle spiral ridge. That is, a large number of electromagnetic steel plates are displaced little by little by being sequentially pressed in the circumferential direction through the engagement between the protrusions and the grooves accompanying the insertion of the shaft. Thereby, a skew is provided in the core.

  According to the method for manufacturing the embedded magnet type rotor of the present invention, the magnetization rate of the field permanent magnet can be ensured.

The perspective view of the rotor of 1st Embodiment. The block diagram which shows the manufacturing apparatus of the rotor of 1st Embodiment, and the manufacturing process of a rotor. The top view which shows the principal part when the rotor of 2nd Embodiment is seen from the axial direction. The block diagram which shows the manufacturing process of the rotor of 2nd Embodiment, and the manufacturing process of a rotor. (A), (b) is a plane which shows the principal part when a rotor is seen from the axial direction in order to demonstrate the variation of the deformation | transformation return process which is one of the manufacturing processes of the rotor in 2nd Embodiment. Figure. FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 5A for explaining a variation of the deformation return process, which is one of the manufacturing processes of the rotor according to the second embodiment. (A), (b) is a perspective view which shows the principal part of a rotor in order to demonstrate the variation of the deformation | transformation return process which is one of the manufacturing processes of the rotor of 3rd Embodiment. (A) is the perspective view of the rotor for demonstrating the manufacturing method of the rotor in 4th Embodiment, (b) was seen from the direction which piles the punching steel plate which is a component of the rotor of 4th Embodiment. Plan view. (A), (b) is the 9-9 sectional view taken on the line of FIG. 8 (a) which shows the mode of the magnet hole before and behind skew formation. The perspective view of the rotor for demonstrating the variation of the manufacturing method of the rotor in 4th Embodiment. Sectional drawing which shows the principal part of the rotor for demonstrating the manufacturing method of the rotor in 5th Embodiment. The top view which shows the principal part of a rotor when the conventional rotor is seen from the axial direction.

<First Embodiment>
Hereinafter, a first embodiment of a method for manufacturing an embedded magnet type rotor will be described. The embedded magnet type rotor constitutes an IPM motor (Interior Permanent Magnet Motor). The IPM motor is used as a generation source of steering assist force in an electric power steering device (EPS), for example.

<Configuration of rotor>
First, the configuration of the rotor will be described.
As shown in FIG. 1, the rotor 11 includes a cylindrical rotor core 12 formed by laminating a plurality of electromagnetic steel plates 12 a and ten permanent magnets 13 embedded in the rotor core 12.

  An insertion hole 14 into which a motor shaft (not shown) is inserted is provided at the center of the rotor core 12. The insertion hole 14 penetrates along the axial direction of the rotor core 12. Further, around the insertion hole 14 of the rotor core 12, ten magnet holes 15 equal in number to the permanent magnets 13 are provided. Each magnet hole 15 penetrates along the axial direction of the rotor core 12. When the rotor core 12 is viewed from the axial direction, the magnet holes 15 are provided at regular intervals along the circumferential direction of the rotor core 12. When the rotor core 12 is viewed from the axial direction, each magnet hole 15 has a U-shape that opens from the inner peripheral surface of the rotor core 12 toward the outer peripheral surface. A permanent magnet 13 is embedded in each magnet hole 15. In this example, a resin-bonded bonded magnet is employed as the permanent magnet 13. This bonded magnet is manufactured by molding and magnetizing a mixture of magnet powder (magnetic powder) and synthetic resin (binder / binder) into a predetermined shape.

<Method for manufacturing rotor>
Next, a method for manufacturing the rotor will be described. The rotor core 12 is manufactured in advance by laminating a plurality of electromagnetic steel plates 12a obtained by punching with a press. In addition, a granular magnet material (pellet) is prepared. The magnet material is obtained by mixing or kneading a magnet powder such as a rare earth magnet and a synthetic resin and molding and solidifying the powder into a predetermined shape (for example, granular shape). As the synthetic resin, any of a thermoplastic resin and a thermosetting resin may be adopted as long as fluidity can be secured.

[1. Extrusion process]
As shown in FIG. 2, when manufacturing the rotor 11, first, the magnet material 13 a is formed into a belt-shaped (sheet-shaped) plate using an extruder 21.

  The extrusion molding machine 21 includes a hopper 22, a cylinder 23, a screw 24, a nozzle (die) 25, and a heater 26. The hopper 22 and the heater 26 are provided on the outer wall of the cylinder 23, respectively. The screw 24 is provided inside the cylinder 23. The nozzle 25 is provided at the tip of the cylinder 23 (the right end in the figure). The nozzle 25 is an extrusion die through which a molded product is extruded, and its cross-sectional shape is set according to the cross-sectional shape of the product (here, a rectangular cross-section when the U-shape is developed into a flat plate shape).

  The hopper 22 is charged with a granular magnet material 13a. The magnet material 13 a put into the hopper 22 is fed into the cylinder 23. The magnet material 13 a fed into the cylinder 23 is melted by receiving heat from the heater 26 while being fed toward the nozzle 25 through the rotation of the screw 24. The molten magnet material 13a is pushed out of the nozzle 25 through the rotation of the screw 24, whereby a strip-shaped molded product 13b having a rectangular cross-sectional shape is continuously formed. At this time, the thickness of the molded product 13 b is larger than the thickness of the magnet hole 15. Further, the width of the molded product 13b is approximately the same as the width when the U-shaped magnet hole 15 is developed in a planar shape.

[2. Rolling process]
Next, the continuously extruded product 13b is sent to the rolling mill 31 by a conveying device such as a conveyor (not shown). The molded product 13b is maintained in a state having flexibility before solidification.

  The rolling mill 31 has two rollers 32 and 33. Between these rollers 32 and 33, the molded product 13b sent by the conveying device is passed. The two rollers 32 and 33 rotate in the direction in which the molded product 13b is sent out by a driving device (not shown), that is, inward from each other. For example, of the two rollers 32 and 33, the roller 32 positioned at the upper portion in the figure rotates in the counterclockwise direction indicated by the arrow α, and the roller 33 positioned at the lower portion in the drawing rotates in the clockwise direction indicated by the arrow β. . The distance between the two rollers 32 and 33 is set to be approximately equal to or slightly longer than the thickness of the magnet hole 15. For this reason, the molded product 13b is gradually rolled (compressed) by passing between the two rollers 32 and 33. By rolling the molded product 13b, the thickness of the molded product 13b becomes thinner than the thickness before rolling. The thickness of the molded product 13b after rolling is preferably about the same as or slightly larger than the thickness of the magnet hole 15. The width of the molded product 13b after the rolling is maintained at the same level as the width when the U-shaped magnet hole 15 is developed in a planar shape.

[3. Orientation magnetization process]
Next, the molded product 13 b delivered from the rolling mill 31 is oriented and magnetized using the magnetizer 41.

  The magnetizer 41 has two permanent magnets 42 and 43. As these permanent magnets 42 and 43, for example, neodymium-iron-boron (Nd-Fe-B) based sintered magnets are employed. The two permanent magnets 42 and 43 are opposed to each other via a molded product 13b fed from the rolling mill 31 (two rollers 32 and 33). The two permanent magnets 42 and 43 are provided such that different magnetic poles (N pole and S pole) face each other through the molded product 13b. The molded product 13b delivered from the rolling mill 31 is oriented and magnetized by passing between the two permanent magnets 42 and 43. A magnetic flux (magnetic field) φ in a direction (vertical direction in the figure) orthogonal to the width direction is applied to the molded product 13b. When the magnetic flux φ passes through the molded product 13b, the molded product 13b is magnetized and exhibits a function as a permanent magnet.

  The thickness of the molded product 13b is substantially constant. In addition, the distance between the two permanent magnets 42 and 43 is substantially constant. For this reason, when the molded product 13b passes between the two permanent magnets 42 and 43, a magnetic field having a certain degree of strength (magnetic flux density) is uniformly applied to the molded product 13b. Since the entire molded product 13b passing between the two permanent magnets 42 and 43 is fully oriented and magnetized, it is possible to further increase the orientation rate and the magnetization rate of the molded product 13b (permanent magnet). is there. So-called uneven magnetization, and hence variations in magnetic characteristics as a permanent magnet are also suppressed.

[4. Cutting process]
Next, the magnetized molded product 13 b sent out from the magnetizer 41 is cut into a certain length using the cutting machine 51.

  The cutting machine 51 has a blade 52. The blade 52 extends along the width direction orthogonal to the thickness direction of the molded product 13b after magnetization. The blade 52 moves between an initial position and a cutting position through the operation of a drive mechanism (not shown). The initial position is a position away from the molded product 13b. The cutting position is a position for cutting the molded product 13b.

  The blade 52 is moved from the initial position to the cutting position at a timing when the molded product 13b is fed by a predetermined cutting length with reference to the cutting position of the blade 52. Thereby, the molded product 13 b is cut by the blade 52. After the cutting of the molded product 13b is completed, the blade 52 is returned from the cutting position to the initial position. Thereafter, every time the molded product 13b is fed by a predetermined cutting length, the blade 52 repeats the same operation to cut the molded product 13b to a predetermined cutting length. In this example, the predetermined cutting length is set to a length comparable to the axial length of the rotor core 12 (magnet hole 15).

[5. Transformation process]
Next, the flat molded product 13 b cut by the cutting machine 51 is deformed into a U shape corresponding to the shape of the magnet hole 15 using the bending machine 61.

  The bending machine 61 has two rollers 62 and 63 and a guide ball 64. The two rollers 62 and 63 are provided in a V-shaped posture. That is, in the width direction of the molded product 13b introduced into the bending machine 61, the distance between the two rollers 62 and 63 is from the first end portion (the lower end portion in the drawing) to the second end portion (the lower end portion in the figure). It gradually becomes longer toward the upper end in the figure. The guide ball 64 is provided between the two rollers 62 and 63. A gap is formed between the guide ball 64 and the two rollers 62 and 63.

  The flat molded product 13 b is deformed into a U shape by passing between the two rollers 62 and 63 and the guide ball 64. The flat molded product 13b is deformed so that both side portions in the width direction follow the two rollers 62 and 63, respectively, so that the guide balls 64 are close to each other. As the molded product 13b is introduced between the two rollers 62 and 63 and the guide ball 64, the molded product 13b is continuously deformed into a U-shape by sandwiching the guide ball 64 therebetween. When the molded product 13b passes between the two rollers 62 and 63 and the guide ball 64, the molded product 13b is deformed into a U shape over the entire length from the front end portion to the rear end portion. Thereby, the U-shaped permanent magnet 13 is manufactured.

[6. Insertion process]
Next, the molded product 13b deformed into a U shape is inserted (press-fitted) into the magnet hole 15. At this time, the molded product 13b is not yet solidified and maintains flexibility.

  When the molded product 13b is compressed in the thickness direction in the previous rolling process and is bent and deformed in the previous deformation process, when the rolling process and the deformation process are completed and the external force on the molded product 13b is released, A so-called spring back occurs in the molded product 13b. Spring back refers to a phenomenon in which elastic deformation generated in the molded product 13b attempts to return to its original shape. When the U-shaped molded product 13b is inserted into the magnet hole 15, a springback occurs in the molded product 13b, thereby increasing the thickness or widening the U-shaped opening width. At this time, since the molded product 13b maintains flexibility, when the gap is formed with the inner wall surface of the magnet hole 15, the molded product 13b is deformed so as to fill the gap. For this reason, the clearance gap between the magnet hole 15 and the permanent magnet 13 can be eliminated. In addition, the loss of magnetic flux generated from the permanent magnet 13 is reduced by eliminating the gap serving as the magnetic resistance. Therefore, the magnetic flux generated from the permanent magnet 13 can be used effectively.

[7. Solidification process]
After the molded product 13b (permanent magnet 13) is inserted into the magnet hole 15 of the rotor core 12, if the molded product 13b is cooled and solidified, the manufacture of the rotor 11 is completed.

<Effect of the first embodiment>
Therefore, according to the present embodiment, the following effects can be obtained.
(1) By orienting and magnetizing the permanent magnet 13 that is a bonded magnet externally, the orientation rate and magnetization rate of the permanent magnet 13 are increased. For example, when manufacturing the U-shaped permanent magnet 13, first, the flat molded product 13b is manufactured from the magnet raw material 13a. Since the molded product 13b has a flat plate shape, a uniform magnetic field can be uniformly applied to the entire molded product 13b. It is also easy to bring the molded product 13b into a magnetic saturation (full magnetization) state. After the magnetization of the molded product 13b is completed, the flat molded product 13b is deformed into a U shape. Therefore, a constant magnetization rate is ensured regardless of the shape and part of the rotor core 12 or the permanent magnet 13. Moreover, the output torque of an IPM motor is raised by using the rotor 11 manufactured in this way.

  (2) The molded product 13b oriented and magnetized outside is inserted into the magnet hole 15 of the rotor core 12 before solidifying. Thereafter, the gap between the permanent magnet 13 and the magnet hole 15 is closed by a so-called spring back of the deformed molded product 13b. In particular, when the gap in the magnetic path direction of the permanent magnet 13 is closed, the magnetic resistance due to the gap is suppressed. For this reason, it becomes possible to utilize the magnetic flux of the permanent magnet 13 more effectively. It is also possible to reduce the size of the rotor 11 and thus the IPM motor.

  (3) There is also a method of magnetizing the molded product 13 b by embedding the magnet material 13 a (molded product 13 b) in each magnet hole 15 of the rotor core 12 and then applying a magnetic flux from the outside of the rotor core 12. When this magnetizing method is employed, the installation space of the magnetic field generation source (permanent magnet or coil) for magnetization is restricted by the interval between the magnet materials 13 a in the circumferential direction of the rotor core 12. In this regard, according to the manufacturing method of this example, the molded product 13b is magnetized outside the rotor core 12, so that it is not necessary to provide a magnetic field generating source for magnetizing around the rotor core 12. Therefore, regardless of the interval between the magnet materials 13a in the circumferential direction of the rotor core 12, the physiques of the permanent magnets 42 and 43, which are magnetic field generation sources for magnetization, are increased as necessary, and a higher magnetic flux is generated by the magnet material 13a. It is also easy to apply.

  (4) There is also a method for securing the magnetization rate of the permanent magnet by dividing the rotor core into a plurality of core pieces and magnetizing each core piece. However, in this case, since a single rotor core is configured by combining a plurality of core pieces, the strength of the rotor is insufficient, and there is a possibility that high-speed rotation cannot be supported. In this respect, according to the manufacturing method of this example, it is not necessary to divide the rotor core 12, and therefore it is easy to ensure the strength of the rotor that can withstand high-speed rotation.

<Second Embodiment>
Next, a second embodiment of the method for manufacturing the embedded magnet type rotor will be described. This example differs from the first embodiment in that the field permanent magnet is divided into two. The rotor core has the same configuration as the rotor core shown in FIG.

  As shown in FIG. 3, when the rotor core 12 is viewed from the axial direction, two permanent magnets 13 are inserted into the U-shaped magnet holes 15. There is basically no gap between the two permanent magnets 13 and 13 and the magnet hole 15. However, in the two permanent magnets 13, 13, a gap δ is formed between two end portions located at the U-shaped bottom portion 15 a of the magnet hole 15.

Now, the manufacturing method of the rotor 11 of this example is as follows.
As shown in FIG. 4, a plate-shaped molded product 13 b corresponding to one permanent magnet 13 is manufactured through an extrusion molding process, a rolling process (first time), an orientation magnetization process, and a cutting process. These four steps are basically performed using the extrusion molding machine 21, the rolling mill 31, the magnetizer 41, and the cutting machine 51, as in the first embodiment. In addition, the thickness of the molded product 13b obtained through the cutting process is approximately the same as the thickness of the magnet hole 15. Further, the width of the molded product 13b is slightly shorter than half of the width of the molded product 13b in the first embodiment. It is about the same as the width when the half U-shaped permanent magnet 13 is developed in a planar shape.

[Rolling process: 2nd time]
Next, the molded product 13 b is further rolled (compressed) by the rolling mill 71. The rolling mill 71 basically has the same configuration as the previous rolling mill 31. The distance between the two rollers 72 and 73 is set to be shorter than the thickness of the magnet hole 15. The molded product 13 b is further compressed by passing between the two rollers 72 and 73. However, a side mold (not shown) that restricts deformation in the width direction of the molded product 13b accompanying this compression may be provided. In this way, it is possible to reduce the thickness of the molded product 13b while keeping the width of the molded product 13b constant. The thickness (length in the magnetizing direction) of the molded product 13b is finally thinner than the thickness of the magnet hole 15.

[Deformation process]
Next, the molded product 13b that has been further compressed and deformed through the second rolling step is deformed into a shape that can be inserted into the magnet hole 15 using the bending machine 61 (see FIG. 2) before the deformation returns. . Here, the molded product 13b is curved in a semi-U shape. The half-U shape refers to a shape obtained by cutting a U-shape in half at the bottom. That is, when two molded products 13b and 13b inserted into one magnet hole 15 are combined, one U-shape is formed.

[Insertion process]
Next, the two molded products 13b and 13b deformed in a semi-U shape are inserted into one magnet hole 15, respectively. At this time, the two molded products 13b and 13b are before solidification and maintain flexibility. When the two molded products 13b and 13b are inserted into the magnet hole 15, a gap caused by the difference between the thickness of the molded product 13b and the thickness of the magnet hole 15 is between the molded products 13b and 13b and the magnet hole 15. Is formed.

[Deformation return process]
Next, using the deformation of the two molded products 13b and 13b, the gap between the molded products 13b and 13b and the inner wall surface of one magnet hole 15 is filled. For example, there are two types A and B described below as deformation types (patterns) of the molded product 13b for filling the gap.

A. A method of utilizing the natural shape recovery of the compression-deformed and curved-deformed product 13b.
B. A method of positively deforming the compression-deformed and curved deformed product 13b.
Type A is a method of using a springback generated in the molded product 13b, as in the first embodiment. A springback is generated in the molded product 13b, so that a gap between the molded products 13b and 13b and the inner wall surface of the magnet hole 15 is filled. That is, the thickness of the compression-deformed molded product 13b attempts to return to the thickness before compression, or the curved portion of the molded product 13b attempts to return to the original flat plate shape. Thereby, the soft molded product 13b before solidification is in close contact with the inner wall of the magnet hole 15 without a gap.

Type B is a method of positively deforming the molded products 13b and 13b by applying an external force to the molded products 13b and 13b, rather than waiting for a natural shape recovery by springback.
As indicated by arrows in FIG. 5A, for example, in two molded products 13 b and 13 b inserted into one magnet hole 15, with respect to two ends located at the bottom of the U-shape of the magnet hole 15, External forces F1 and F2 are applied in directions opposite to each other and in directions intersecting with the thickness direction (magnetization direction) of the molded products 13b and 13b.

  As shown in FIG. 5B, by applying external forces F1 and F2, the two molded products 13b and 13b are deformed so as to swell in the thickness direction. By increasing the thicknesses of the two molded products 13b and 13b, the two molded products 13b and 13b are in close contact with the inner wall surface of the magnet hole 15 without a gap.

As a specific means for applying the external forces F1 and F2 to the two molded products 13b and 13b, the following pressing mechanism may be used.
As shown in FIG. 6, the pressing mechanism 81 has two pressing members 82 and 83 and one wedge 84. The two pressing members 82 and 83 and the wedge 84 are inserted between the two molded products 13b and 13b in the magnet hole 15 through the operation of a driving mechanism (not shown). However, the wedge 84 is driven between the two pressing members 82 and 83. Further, the insertion direction of the two pressing members 82 and 83 and the insertion direction of the single wedge 84 are opposite to each other. For example, two pressing members 82 and 83 are inserted into the magnet hole 15 from above in the figure, while one wedge 84 is inserted into the magnet hole 15 from below in the figure. Incidentally, the insertion direction of the two pressing members 82 and 83 and the insertion direction of one wedge 84 may be the same. In this case, after the two pressing members 82 and 83 are previously inserted and set between the two molded products 13b and 13b in the magnet hole 15 from the lower side in the figure, one wedge 84 is inserted into the magnet hole from the lower side in the figure. 15 may be inserted between the two pressing members 82, 83.

  The length in the insertion direction of the two pressing members 82 and 83 is set to be approximately the same as or slightly longer than the length of the magnet hole 15 in the axial direction of the rotor core 12. The two pressing members 82 and 83 have slope surfaces 82a and 83a, respectively. These inclined surfaces 82a and 83a are provided over the entire length in the insertion direction of the pressing members 82 and 83, respectively. The two pressing members 82 and 83 are arranged in such a direction that the two inclined surfaces 82a and 83a face each other and from the first end portion (lower end in the figure) that is the end portion on the insertion side with respect to the magnet hole 15. It inserts in the magnet hole 15 in the attitude | position which the space | interval of the two gradient surfaces 82a and 83a becomes wide as it goes to an edge part (upper end in a figure).

  The length of the wedge 84 in the insertion direction is set longer than the length of the two pressing members 82 and 83 in the insertion direction. In the wedge 84, tapered surfaces 84a and 84b are provided on two side surfaces on the two pressing members 82 and 83 (gradient surfaces 82a and 83a) side, respectively. These tapered surfaces 84a and 84b are provided over the entire length in the insertion direction of the wedge 84, respectively. Further, these tapered surfaces 84a and 84b increase from each other toward the second end (lower end in the figure) from the first end (upper end in the figure) which is the end of the wedge 84 on the insertion side with respect to the magnet hole 15. It is inclined so that the interval of becomes wide. The degree of inclination of the two tapered surfaces 84a and 84b is set to be approximately the same as the degree of inclination of the two inclined surfaces 82a and 83a.

  Now, when filling the gap between the two molded products 13b, 13b and one magnet hole 15 in the deformation return step, first, the two pressing members 82, 83 are inserted into the magnet hole 15 from above in the drawing. To do. Next, a wedge 84 is driven between the two pressing members 82 and 83 from below in the drawing. The external force in the direction in which the wedge 84 is driven (upward in the figure) is a direction in which the interval between the two pressing members 82 and 83 is increased through sliding contact between the two inclined surfaces 82a and 83a and the two tapered surfaces 84a and 84b (see FIG. It is converted into a force in the horizontal direction. Therefore, as the wedge 84 is driven, the two pressing members 82 and 83 move in opposite directions to press the two molded products 13b and 13b (permanent magnets 13 and 13), respectively. The pressing force by the two pressing members 82 and 83 acts in a direction intersecting with the thickness direction (magnetization direction) of the two molded products 13b and 13b. Accordingly, the two molded products 13b and 13b are pressed against the tips of the U-shaped arm portions in the magnet holes 15, respectively. After the pressing, the two molded products 13b and 13b are deformed so that the width in the direction along the magnet hole 15 (the length in the direction intersecting the thickness direction) is narrowed, while the width is It is deformed so that the thickness increases as it becomes narrower. As a result, a gap between the two molded products 13b and 13b and one magnet hole 15 is filled.

[Solidification process]
Thereafter, when the two molded products 13b and 13b (permanent magnets 13 and 13) are cooled and solidified, the manufacture of the rotor 11 is completed.

<Effects of Second Embodiment>
Therefore, according to the present embodiment, the following effects can be obtained.
(1) The molded product 13 b is compressed and deformed to make the molded product 13 b thinner than the magnet hole 15, and then the molded product 13 b is inserted into the magnet hole 15. For this reason, it becomes easy to insert the molded product 13 b into the magnet hole 15.

  (2) In the deformation return step, after the molded product 13b is inserted into the magnet hole 15, when the shape of the molded product 13b is naturally restored, the molded product is not provided with a separate configuration for restoring the shape of the molded product 13b. A gap between 13b and the magnet hole 15 can be filled.

  (3) In the deformation return step, when the shape of the molded products 13b and 13b is more positively restored rather than waiting for the natural shape recovery by the springback, the molded product 13b is moved to the inner wall surface of the magnet hole 15 earlier. Can be in close contact with. By completing the deformation return process earlier, the manufacturing efficiency of the rotor 11 can be improved.

  (4) In a state where the two permanent magnets 13 and 13 are fixed inside one magnet hole 15, a gap δ as a space portion exists between one permanent magnet 13 and the other permanent magnet 13. . For this reason, when a part of the rotor core 12 is interposed between the two permanent magnets 13, 13, that is, when there is no gap δ and one magnet hole 15 is an independent hole corresponding to one permanent magnet 13. In comparison, the short-circuit magnetic flux can be reduced. Since the amount of magnetic flux toward the stator is ensured as much as the short-circuit magnetic flux decreases, the utilization efficiency of the permanent magnet 13 can be improved.

<Third Embodiment>
Next, a third embodiment of a method for manufacturing an embedded magnet type rotor will be described. In the first embodiment, the U-shaped molded product 13b obtained through the deformation process is press-fitted into the magnet hole 15, but the following may be used.

  As shown in FIG. 7A, the length of the U-shaped molded product 13b obtained through the deformation process is set longer than the length of the rotor core 12 (magnet hole 15) in the axial direction. For this reason, when the molded product 13 b is inserted into the magnet hole 15 in the insertion step, at least one end of the molded product 13 b protrudes from the magnet hole 15 in the axial direction of the rotor core 12. Further, the thickness of the molded product 13 b is set to be thinner than the thickness of the magnet hole 15. For this reason, a gap is formed between the molded product 13 b and the magnet hole 15.

  After the insertion process is completed, a deformation return process for filling a gap between the molded product 13b and the inner wall surface of the magnet hole 15 is performed using the deformation of the molded product 13b. For example, when both ends of the molded product 13b protrude from the upper and lower openings of the magnet hole 15, external forces F3 and F4 directed in the compression direction along the axial direction of the rotor core 12 are applied to the molded product 13b. Thereby, the molded product 13b is compressed along the axial direction.

  As shown in FIG. 7B, the thickness of the molded product 13b increases as the molded product 13b is compressed in the axial direction. As the thickness increases, the molded product 13 b comes into close contact with the inner wall surface of the magnet hole 15. In addition, when the molded product 13b is compressed until the upper and lower surfaces in the drawing of the molded product 13b coincide with the upper and lower surfaces of the rotor core 12, the molded product is just enough to eliminate the gap between the molded product 13b and the magnet hole 15. The thickness and length of 13b are set.

Even if it does in this way, the effect similar to (1), (3), (4) in 1st Embodiment can be acquired. This example may be applied to the second embodiment.
<Fourth embodiment>
Next, a fourth embodiment of the method for manufacturing the embedded magnet type rotor will be described. This example may be applied to any of the first to third embodiments.

  In an IPM motor, a skew (tilt) may be provided in the magnetic pole of the rotor for the purpose of reducing cogging or torque ripple. First, in this example, a configuration that is a prerequisite for forming a skew in the rotor will be described.

  As shown in FIG. 8A, in the rotor core 12, a groove 14 a is provided on the inner peripheral surface of the insertion hole 14. The groove 14 a is provided over the entire length of the insertion hole 14 in the axial direction. That is, as shown in FIG. 8B, a large number of electromagnetic steel plates 12a constituting the rotor core 12 have keyhole-shaped hole portions 12b corresponding to the insertion holes 14 and the grooves 14a, respectively. One insertion hole 14 and one groove 14a are formed by laminating a large number of electromagnetic steel plates 12a.

  As shown in FIG. 8A, a protrusion 91 a is provided on the outer peripheral surface of the portion of the motor shaft 91 inserted into the insertion hole 14 that is inserted (press-fitted) into the insertion hole 14 of the rotor core 12. The protrusion 91 a is gently twisted along the axis of the motor shaft 91. The degree of twist of the protrusion 91a is set according to the required skew angle. The length (width) of the motor shaft 91 in the circumferential direction is set so that the protrusion 91 a can be inserted into the groove 14 a along the axial direction of the rotor core 12.

The skew is provided as follows. The skew formation process is performed between the deformation return process and the solidification process.
Before the molded product 13b (permanent magnet 13) inserted into the magnet hole 15 is solidified, the insertion hole 14 of the rotor core 12 with the positions of the grooves 14a of the rotor core 12 and the protrusions 91a of the motor shaft 91 matched. The motor shaft 91 is inserted from above in the figure. As the motor shaft 91 is inserted into the insertion hole 14, the protrusion 91a is also inserted into the groove 14a. As indicated by the arrows in FIG. 8 (a), as the protrusions 91a are inserted into the grooves 14a, the multiple electromagnetic steel plates 12a constituting the rotor core 12 follow the gentle spiral protrusions 91a. Move sequentially in the circumferential direction. That is, the positions of the plurality of electromagnetic steel plates 12a are slightly shifted by being sequentially pressed in the circumferential direction through the engagement of the protrusions 91a and the grooves 14a accompanying the insertion of the motor shaft 91.

  As shown in FIGS. 9A and 9B, each electromagnetic steel sheet moves in the circumferential direction following the protrusion 91a, so that the shape of the magnet hole 15 is also deformed in the circumferential direction. Further, since the molded product 13b (permanent magnet 13) inserted into the magnet hole 15 is before solidification, the shape of the molded product 13b is also deformed in accordance with the movement of each electromagnetic steel sheet in the circumferential direction. Actually, each electromagnetic steel plate 12a is slightly displaced in the circumferential direction of the rotor core 12 so that the inner wall surface of the magnet hole 15 has a stepped shape. In FIGS. The inner wall surface of the magnet hole 15 is shown in a simplified manner as a slope inclined toward the moving direction of 12a.

  When the motor shaft 91 is inserted to a predetermined insertion position, the skew forming process is completed. At this time, the portion of the motor shaft 91 where the protrusion 91a is provided is maintained in a state of being inserted over the entire length of the insertion hole 14. Each electromagnetic steel sheet 12a is positioned on the basis of the protrusion 91a, so that each electromagnetic steel sheet 12a is maintained in a laminated state with a predetermined skew angle. Further, the molded product 13 b (permanent magnet 13) is also maintained in a shape having a predetermined skew angle following the shape of the magnet hole 15.

Incidentally, this example may be implemented with the following modifications.
That is, when the rotor core 12 and the motor shaft 91 are serrated and connected, serration teeth as a plurality of protrusions are provided on the peripheral surface of the motor shaft 91, while a plurality of serration teeth are provided on the inner peripheral surface of the insertion hole 14 of the rotor core 12. A serration groove is provided as a groove. As shown by a two-dot chain line in FIG. 8A, the serration teeth 91 b are provided in a spiral shape that is gently twisted along the axis of the motor shaft 91. Even in this manner, the large number of electromagnetic steel plates 12a move in small amounts in the circumferential direction sequentially through the engagement between the serration teeth and the serration grooves accompanying the insertion of the motor shaft 91.

  Further, as indicated by arrows in FIG. 10, skew may be provided by twisting the rotor core 12 by applying a rotational force in the opposite direction to the upper and lower portions of the rotor core 12. Even if it does in this way, each electromagnetic steel plate 12a can be shifted little by little toward the circumferential direction. After providing the skew to the magnetic pole of the rotor 11, the motor shaft 91 can be inserted (press-fitted) into the insertion hole 14 of the rotor 11 and fixed, so that the return of the twist of the magnetic pole can be suitably suppressed. In this case, the protrusion 91a or each serration tooth may be provided so as to extend straight along the axis of the motor shaft 91.

<Effect of the fourth embodiment>
Therefore, according to the present embodiment, the following effects can be obtained.
(1) A skew can be provided in the rotor 11 only by press-fitting the motor shaft 91. For this reason, when the skew is provided in the rotor 11, the assembly work of the rotor 11 can be simplified. Further, by providing a skew in the rotor 11, the cogging torque or torque ripple of the IPM motor is reduced.

  (2) Along with the insertion of the motor shaft 91, the multiple electromagnetic steel plates 12a move so as to be sequentially twisted in the circumferential direction following the protrusions 91a. When the electromagnetic steel sheet 12a is pressed, the molded product 13b is also deformed so as to be twisted in the circumferential direction. Thereby, the clearance gap between the magnet hole 15 and the molded product 13b (permanent magnet 13) is further eliminated. In addition, the molded product 13b can be more firmly fixed to the rotor core 12.

  (3) Since the protrusions 91a (or serration teeth) engage with the grooves 14a (or serration grooves) in the circumferential direction of the rotor core 12, torque transmission between the motor shaft 91 and the rotor core 12 is more reliably performed. Is called.

  (4) After inserting the molded product 13b into the magnet hole 15, the skew can be easily formed by applying a twisting force to the rotor 11. Incidentally, when the molded product 13b is inserted into the magnet hole 15 after the skew is provided in the rotor core 12, the magnet hole 15 has a twisted shape corresponding to the skew, so that it is difficult to insert the molded product 13b.

<Fifth embodiment>
Next, a fifth embodiment of a method for manufacturing an embedded magnet type rotor will be described. This example may be applied to any of the first to fourth embodiments.

  The plurality of electromagnetic steel plates 12a constituting the rotor core 12 are each formed through punching with a press. For this reason, in the electromagnetic steel sheet 12a, the outer peripheral portion, the hole portion corresponding to the insertion hole 14, and the punched portion (sheared portion) such as the hole portion corresponding to the magnet hole 15 have a burr 12c. Remains.

  As shown in FIG. 11, for example, a corner portion where the inner peripheral surface of the hole portion corresponding to the magnet hole 15 of each electromagnetic steel plate 12 a intersects the lower surface in the drawing protrudes downward in the drawing, which is the shearing direction. A burr 12c is formed. And each electromagnetic steel plate 12a is laminated | stacked so that all the sheared directions may correspond. For this reason, for example, the burrs 12c existing on the inner wall surface of the magnet hole 15 all face the same direction (downward in the drawing).

  As indicated by a two-dot chain line in FIG. 11, in the insertion step, the molded product 13b (permanent magnet 13) is inserted into the magnet hole 15 from the direction opposite to the direction in which the burr 12c extends (upward in the drawing).

<Effect of Fifth Embodiment>
Therefore, according to the present embodiment, the following effects can be obtained.
(1) Since the direction in which the molded product 13b is inserted is the same as the direction in which the burr 12c extends, when the molded product 13b is inserted into the magnet hole 15, the molded product 13b is not easily caught by the burr 12c. For this reason, the molded product 13 b can be smoothly inserted into the magnet hole 15.

(2) Further, when the molded product 13b is inserted into the magnet hole 15, since the molded product 13b is not easily caught by the burr 12c, the molded product 13b can be prevented from being damaged.
<Other embodiments>
In addition, you may implement the said embodiment as follows.

-Although the rotor core 12 in each embodiment consisted of the electromagnetic steel plate 12a, you may use soft magnetic materials, such as electromagnetic soft iron, for example.
-Although the rotor 11 in each embodiment was taken as the 10 pole structure which has the 10 permanent magnets 13, the magnetic pole number of the rotor 11 is not specifically limited, You may change suitably.

  In each embodiment, the rotor 11 (rotor core 12) and the motor shaft 91 may be fixed by caulking or may be fixed by welding. The same applies to a plurality of electromagnetic steel sheets that constitute the rotor core 12.

  The field permanent magnet 13 in each embodiment has a U-shaped cross-section perpendicular to the axial direction of the rotor core 12, but the shape of the permanent magnet 13 is not limited to this. For example, the permanent magnet 13 may have a V-shaped cross section perpendicular to the axial direction of the rotor core 12. Moreover, the permanent magnet 13 may have a rectangular cross-sectional shape orthogonal to the axial direction of the rotor core 12. That is, when a plurality of rectangular parallelepiped permanent magnets 13 are provided side by side in a V shape or U shape, when a magnetic field for magnetization is applied from the outside, the portion closer to the center portion of the rotor core 12 in the permanent magnet 13 There is concern that the magnetic flux from As described above, when a plurality of permanent magnets 13 are provided in a shape having a portion extending from the center of the rotor 11 toward the outer periphery, the permanent magnets 13 are oriented and attached outside the rotor core 12 as in the embodiments. It is preferably magnetized. In addition, when employ | adopting the rectangular parallelepiped permanent magnet 13, the deformation | transformation process which uses the bending machine 61 becomes unnecessary.

  -In each embodiment, although the magnet raw material 13a was shape | molded into the strip | belt-shaped board using the extrusion molding machine 21, you may utilize injection molding. In this case, the magnet material 13a melted by heating is injected into a cavity provided inside the mold to be formed into a strip-shaped plate.

  DESCRIPTION OF SYMBOLS 11 ... Rotor, 12 ... Rotor core, 12a ... Electromagnetic steel plate, 13 ... Permanent magnet (bonded magnet), 13a ... Magnet material, 13b ... Molded product, 14 ... Insertion hole, 14a ... Groove, 15 ... Magnet hole, 91 ... Motor shaft 91a.

Claims (12)

A cylindrical core and a resin-bonded bond magnet embedded in each of a plurality of magnet holes provided in the core, and the magnet hole is a circumferential surface from the center of the core when viewed from the axial direction of the core. In the manufacturing method of an embedded magnet type rotor having a portion extending toward
An orientation magnetizing step of orienting and magnetizing the molded product before solidification outside the core, wherein the melted magnet material of the bonded magnet is molded,
An embedded step of inserting the bonded magnet before solidification obtained through the orientation and magnetization step into the magnet hole. In the manufacturing method of the interior magnet type rotor according to claim 1,
Assuming that the magnet hole includes a curved portion intersecting with the radial direction of the core when viewed from the axial direction of the core,
A step that is performed prior to the orientation magnetization step, and a molding step that molds the molten magnet material into a flat molded product,
It is a step performed between the orientation magnetization step and the insertion step, and the flat bonded magnet obtained through the orientation magnetization step is shaped into a shape corresponding to the shape of the magnet hole before solidification. A manufacturing method of an embedded magnet type rotor having a deformation step of deforming. In the manufacturing method of the interior magnet type rotor according to claim 2,
In the orientation and magnetization step, a method of manufacturing an embedded magnet type rotor in which a magnetizing magnetic field is applied to the flat plate-shaped product in a direction along a thickness direction thereof. In the manufacturing method of the interior magnet type rotor of Claim 2 or Claim 3,
In the insertion step, an embedded magnet type rotor that press-fits the bond magnet, which has been deformed into a shape corresponding to the shape of the magnet hole through the deformation step, into the magnet hole from a direction along the axial direction of the core. Manufacturing method. In the manufacturing method of the interior magnet type rotor of Claim 2 or Claim 3,
It is a process performed between the orientation magnetization process and the deformation process, and the flat bond magnet is compressed in the thickness direction by compressing the flat bond magnet obtained through the orientation magnetization process. A method of manufacturing an embedded magnet type rotor including a compression step of making the thickness of the magnet smaller than the thickness of the magnet hole. In the manufacturing method of the interior magnet type rotor according to claim 5,
A manufacturing method of an embedded magnet type rotor including a deformation return step of closing a gap between the bonded magnet before solidification inserted into the magnet hole through the insertion step and an inner wall surface of the magnet hole. In the manufacturing method of the interior magnet type rotor according to claim 6,
In the deformation return step, the bond magnet and the inner wall surface of the magnet hole are utilized by utilizing a phenomenon that the bond magnet before solidification that is elastically deformed in the deformation step or the compression step tries to return to the original shape before elastic deformation. Of manufacturing an embedded magnet type rotor that closes the gap between the rotor and the rotor. In the manufacturing method of the interior magnet type rotor according to claim 6,
In the deformation return step, the bond magnet and the magnet are positively deformed by applying an external force in a direction intersecting the magnetization direction to the bond magnet before solidification inserted into the magnet hole. A manufacturing method of an embedded magnet type rotor that closes a gap between an inner wall surface of a hole. In the manufacturing method of the interior magnet type rotor according to claim 8,
Assuming that the magnet hole is provided in a U-shape and two bonded magnets are inserted into one magnet hole,
In the deformation return step, the bond magnet that is also a magnetizing direction of the bond magnet as viewed from the axial direction of the core by driving a wedge between the two bond magnets inserted into one magnet hole. The manufacturing method of the embedded magnet type rotor which applies the external force to the direction which cross | intersects with respect to the thickness direction of said bonded magnet. In the manufacturing method of the interior magnet type rotor according to claim 8,
Assuming that the molded product is formed longer than the axial length of the core,
In the deformation return step, an external force in a direction along the axial direction of the core is applied to the bond magnet inserted into the magnet hole as a direction intersecting the magnetization direction, thereby attaching the bond magnet. A manufacturing method of an embedded magnet type rotor that closes a gap between the bond magnet and an inner wall surface of the magnet hole by deforming in a thickness direction that is also a magnetic direction. In the manufacturing method of the interior magnet type rotor according to any one of claims 1 to 10,
Assuming that the core is formed by laminating a plurality of electromagnetic steel sheets,
A method of manufacturing an embedded magnet type rotor comprising a step of forming a skew, the step being performed after the inserting step, wherein the skew is provided by twisting the core into which the bonded magnet before solidification is inserted into the magnet hole. In the manufacturing method of the interior magnet type rotor according to claim 11,
The core has an insertion hole through which a shaft passes, and a groove provided on an inner peripheral surface of the insertion hole and extending over the entire length in the axial direction of the core, and
On the premise that a gentle spiral ridge that engages with the groove is provided on the outer peripheral surface of the shaft inserted into the insertion hole,
In the skew forming step, a method of manufacturing an embedded magnet type rotor in which a skew is provided by inserting the shaft into the insertion hole.