JP7224218B2 - Rotor and rotor manufacturing method - Google Patents

Description

The present application relates to a rotor and a method of manufacturing a rotor

Conventionally, in rotors of rotary electric machines such as electric motors, by integrally molding the core and permanent magnets with resin, a highly productive rotor that does not require an adhesive for bonding the core and the permanent magnets has been developed. (see, for example, Patent Document 1). This rotor uses permanent magnets formed with uneven thickness structure, and the positional accuracy of the permanent magnets is also improved.

In addition, in the rotor of an electric motor, which requires higher reliability, a gap is provided between the inner peripheral surface of the permanent magnet and the outer peripheral surface of the core. A rotor is disclosed in which pressure is applied to align the permanent magnets on the outer peripheral surface of the rotor regardless of dimensional variations of the permanent magnets, thereby stabilizing the magnetic field of the rotor (see, for example, Patent Document 2).

Japanese Patent No. 3309844 JP 2018-74765 A

However, all the rotors disclosed in the prior art documents have the problem that the core using a ferromagnetic metal is large and the manufacturing cost of the rotor is high.

The present application has been made to solve the above problems, and an object of the present application is to provide a rotor with high cost performance and a method for manufacturing the rotor.

The rotor disclosed in the present application includes:
a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A rotor comprising a resin that integrally molds a
At least one portion of the surface of the permanent magnet that contacts the resin is subjected to microfabrication by chemical etching or laser processing to improve adhesiveness to the resin.
Further, the rotor disclosed in the present application is
a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A rotor comprising a resin that integrally molds a
The shaft has a radially penetrating hole filled with the resin.

The rotor manufacturing method disclosed in the present application includes:
a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A method of manufacturing a rotor comprising a resin integrally molding a
The shaft is inserted into and supported by the shaft hole provided in the center of the bottom surface of the lower mold having a mold hole hollowed out in a cylindrical shape of the mold,
a plurality of the permanent magnets arranged at equal intervals along the inner peripheral surface of the mold cavity; A component placement process in which the parts are supported by spacers so as to float from the bottom surface of the lower die;
and a resin press-fitting step of press-fitting the resin.

According to the rotor and the method for manufacturing the rotor disclosed in the present application, it is possible to provide the rotor and the method for manufacturing the rotor with high cost performance.

2 is a schematic side view of the rotor according to Embodiment 1. FIG. FIG. 2 is a schematic diagram of the rotor according to Embodiment 1 as seen from the axial direction; FIG. 2 is a schematic cross-sectional view of the rotor according to Embodiment 1 taken along a plane passing through its central axis; FIG. 2 is a schematic cross-sectional view of the rotor according to Embodiment 1 taken perpendicularly to the axial direction; 4 is a schematic side view of another rotor according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view showing an example of locations where surface treatments are applied to the shaft, outer core, and permanent magnets according to Embodiment 1; FIG. 2 is a schematic cross-sectional view showing an example of locations where surface treatments are applied to the shaft, outer core, and permanent magnets according to Embodiment 1; 4 is a schematic cross-sectional view of another rotor according to Embodiment 1. FIG. 4 is a cross-sectional view showing a state in which the shaft, outer core, and permanent magnets according to Embodiment 1 are set in the lower mold of the mold; FIG. 4 is a cross-sectional view showing a state in which the shaft, outer core, and permanent magnets according to Embodiment 1 are set in the lower mold of the mold; FIG. FIG. 8 is a schematic cross-sectional view taken perpendicularly to the axial direction of the rotor according to Embodiment 2; FIG. 11 is a schematic cross-sectional view of the rotor according to Embodiment 3 taken perpendicularly to the axial direction; FIG. 10 is a diagram showing a modification of grooves provided in the outer core according to Embodiment 3; FIG. 11 is a schematic cross-sectional view of a rotor according to Embodiment 4 taken along a plane passing through its central axis; FIG. 11 is a schematic cross-sectional view of the rotor according to Embodiment 4 taken perpendicularly to the axial direction;

Embodiment 1.
A rotor and a method for manufacturing the rotor according to the first embodiment will be described below with reference to the drawings.
In this specification, simply referring to the circumferential direction, the radial direction, and the axial direction refer to the circumferential direction, the radial direction, and the axial direction of the rotor.
FIG. 1 is a schematic side view of the rotor 100. FIG.
FIG. 2 is a schematic diagram of the rotor 100 viewed from the axial direction.
FIG. 3 is a schematic cross-sectional view of the rotor 100 taken along a plane passing through its central axis.
FIG. 4 is a schematic cross-sectional view of the rotor 100 taken perpendicularly to the axial direction.
A rotor 100 is composed of a shaft 1 , an outer core 2 , a plurality of permanent magnets 3 and a resin 4 . The rotor 100 is made by setting a shaft 1, an outer core 2, and a plurality of permanent magnets 3 in a mold, injecting a resin 4 into the mold by injection molding or the like, and integrally molding each part. be. The details of the method for manufacturing the rotor 100 will be described later.

As shown in FIG. 4, the outer core 2 has a central hole 2H with an inner diameter larger than the outer diameter of the shaft 1, and projections 21 for positioning the permanent magnets 3 on the outer peripheral surface are arranged at regular intervals in the circumferential direction. It is a cylindrical laminated core in which a plurality of discs are stacked in the axial direction. A ferromagnetic material is used as the material of the outer core 2 . For example, iron, nickel, cobalt, or the like can be used as the ferromagnetic material.

Since the inner diameter of the center hole 2H of the outer core 2 is larger than the outer diameter of the shaft 1, the outer core 2 and the shaft 1 do not contact each other. It is a configuration that exists. In addition, as shown in FIG. 3, the resin 4 also covers the axial end surfaces of the permanent magnet 3 and the outer core 2 as a unit.

The outer core 2 may be improved in adhesiveness by surface treatment or surface processing of the contact surface with the resin 4 in order to improve adhesiveness with the resin 4 when the rotor 100 is integrally molded. Methods of surface treatment of the outer core 2 include chemical etching, microfabrication by laser processing, and grooving or knurling by mechanical processing. Specific places where the surface treatment is applied to the outer core 2 will be described later.

As shown in FIG. 4 , a plurality of permanent magnets 3 are provided along projections 21 provided on the outer core 2 . Although ten permanent magnets 3 are attached in this embodiment, the number of permanent magnets may be freely changed according to the required rotor design.

FIG. 5 is a schematic side view of the rotor 100b.
Also, as shown in FIG. 5, two permanent magnets 3b may be attached in the axial direction. Also, three or more permanent magnets may be attached in the axial direction. As with the outer core 2, the contact surfaces of the permanent magnets 3 and 3b with the resin 4 are surface-treated or surface-processed to improve the adhesiveness with the resin 4 during integral molding of the rotor. You can improve it.

Surface treatment methods include chemical etching, fine processing by laser processing, and grooving or knurling by mechanical processing. Specific places where the permanent magnets 3 and 3b are surface-treated will be described later. The types of permanent magnets 3 and 3b include neodymium magnets, ferrite magnets, and the like. However, in the design of the rotor, non-permanent magnets may be used instead of permanent magnets, such as plastic magnets, if the required magnetic force is satisfied. Other magnets may be used.

As shown in FIG. 3 , the shaft 1 is integrally molded with the resin 4 so that the resin 4 surrounds the shaft 1 . As with the outer core 2, the contact surface of the shaft 1 with the resin 4 is surface-treated or surface-finished to improve the adhesiveness with the resin 4 during integral molding of the rotor. Also good. Surface treatment methods include chemical etching, fine processing by laser processing, and grooving or knurling by mechanical processing.

FIG. 6 is a schematic cross-sectional view showing an example of locations where the surface treatment is applied to the shaft 1, the outer core 2, and the permanent magnets 3. As shown in FIG.
FIG. 7 is a schematic cross-sectional view showing an example of a place where surface treatment is applied to the shaft 1, the outer core 2, and the permanent magnet 3. As shown in FIG.
As shown in FIGS. 6 and 7, a surface-treated portion 1 s is provided in the axial center of the shaft 1 , a surface-treated portion 2 s is provided on the inner peripheral surface of the outer core 2 , and surface-treated portions 3 s are provided on both circumferential end surfaces of the permanent magnet 3 . are provided. This is related to workability of surface treatment. In addition, you may surface-treat the whole of each component.

FIG. 8 is a schematic cross-sectional view of the rotor 100c.
As shown in FIG. 8, a hole H penetrating the shaft 1c in the radial direction may be formed, and the hole H may be filled with resin 4 to increase the strength of the rotor 100c.

As described above, the resin 4 is a resin used when integrally molding the shafts 1 to 1c and the permanent magnets 3 to 3b. A thermoplastic resin, for example, is used as the resin 4 . As described above, the shafts 1 to 1c, the outer core 2, and the plurality of permanent magnets 3 to 3b are integrally molded with the resin 4, and the outer core 2 and the shafts 1 to 1c are not in contact with each other. In the rotors 100 to 100c of the first embodiment, only the resin 4 is in contact with the outer peripheral surfaces of the rotors 1 to 1c.

Next, the manufacturing process of the rotor 100, that is, the process of integrally molding the shaft 1, the outer core 2 and the permanent magnets 3 using the resin 4 will be described.
FIG. 9 is a sectional view showing a state in which the shaft 1, the outer core 2 and the permanent magnet 3 are set in the lower mold 50 of the mold. Also, FIG. 9 is a cross-sectional view of a portion where a positioning spacer 51 exists.
FIG. 10 is a sectional view showing a state in which the shaft 1, outer core 2 and permanent magnet 3 are set in the lower die 50. As shown in FIG. The cutting location is different from that in FIG. 9, and since this is a sectional view of a portion where the spacer 51 does not exist, the outer core 2 and the permanent magnet 3 appear to be floating in the air from the bottom surface of the lower die 50. FIG.

First, the shaft 1, the outer core 2, and the permanent magnet 3 are surface-treated as necessary, and then the shaft 1 and the outer core 2 are set in the lower mold 50 of the mold. At this time, the permanent magnets 3 are set at regular intervals along the inner peripheral surface of the lower die 50 along the projections 21 extending in the axial direction of the outer core 2 (component placement step).

The lower mold 50 has a mold cavity 52 hollowed out in a cylindrical shape. At the center of the bottom surface of the lower mold 50, a shaft hole 53 is provided for supporting the shaft 1 by vertically inserting it. The lower die 50 is also provided with the same number of positioning spacers 51 as the number of permanent magnets 3 in contact with the inner peripheral surface of the die cavity 52 . The spacers 51 are arranged at regular intervals along the inner peripheral surface of the mold cavity. A cross section perpendicular to the circumferential direction of the spacer 51 has an L shape in which a radially outer portion 51a protrudes upward from the paper surface of FIG. 9 more than a radially inner portion 51b. An upper end face 51aup of the outer portion 51a of the spacer 51 contacts one end face 3down of the permanent magnet 3 in the axial direction.

Also, the contact area between the spacer 51 and the permanent magnet 3 is sufficiently smaller than the area of the end surface of the permanent magnet 3 in the axial direction. The spacer 51 also serves as a positioning mechanism for the outer core 2 . Inside the lower die 50, the radially inner surface 3in of the permanent magnet 3 contacts the outer peripheral surface 2out of the outer core 2, and the radially inner surface 51ain of the outer portion 51a of the spacer 51 contacts the axially lower end portion of the outer core 2. The upper end surface 51bup of the inner portion 51b of the spacer 51 contacts the one end surface 2down of the outer core 2 in the axial direction.

Thus, the outer core 2 can be accurately positioned in the lower die 50 by the spacer 51 . Further, the spacer 51 and the protrusion 21 provided on the outer core 2 shown in FIG. Since it is possible to float and hold the resin 4, the flow part of the resin 4 can be ensured.

Instead of the spacer 51 for positioning the lower die, a pin or the like may be attached to the lower die 50 to have the same function as the spacer 51 . Also, the pin itself may be a part of the rotor.

Next, an upper mold (not shown) having a shape obtained by inverting the lower mold 50 is set from above the lower mold 50, and resin is press-fitted into the mold (resin press-fitting step).
By press-fitting the resin 4, the resin 4 spreads throughout the space in the mold. After the resin 4 hardens, the rotor 100 in which the shaft 1, the outer core 2, the permanent magnets 3 and the resin 4 are integrally formed is removed from the mold.

Next, the effects of the rotor 100 and the method of manufacturing the rotor 100 will be described while comparing the techniques of Patent Documents 1 and 2 with the present embodiment. The cores in the techniques of Patent Documents 1 and 2 are in contact with the shaft on the inner peripheral side, and the outer peripheral side of the core is in contact with the inner peripheral side of the permanent magnet. The weight of the electric motor had increased.
In addition, in the techniques of Patent Documents 1 and 2, after the core and the permanent magnet are integrally molded, the shaft is press-fitted into the integrally molded product of the core and the permanent magnet, and the shaft is assembled to the core, so a press-fitting process is required. Met.

According to the rotor 100 and the method of manufacturing the rotor 100 according to the first embodiment, as shown in FIG. Since the space between the core 2 and the shaft 1 is integrally formed using the resin 4, it is possible to reduce the amount of the core material, which is metal, so that the weight of the rotor and the material cost can be reduced.

In addition, since the outer core 2, the permanent magnet 3 and the shaft 1 are simultaneously set in a mold and integrally molded with the resin 4, the process of press-fitting the shaft is not necessary, and there is an effect of improving productivity.

Embodiment 2.
Hereinafter, a rotor and a method of manufacturing the rotor according to the second embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment.
FIG. 11 is a schematic cross-sectional view of the rotor 200 according to Embodiment 2 taken perpendicularly to the axial direction.
In Embodiment 1, as shown in FIG. 4, the shape of the outer peripheral surface and the inner peripheral surface of the permanent magnet 3 in the cross section taken perpendicularly to the axial direction of the rotor 100 is arcuate. Since the adhesion area of the permanent magnet 4 is small and the resin 4 does not exist on the outer peripheral side of the permanent magnet 3, the permanent magnet 3 cannot be pressed from the outer peripheral side to the inner peripheral side.

Therefore, in the second embodiment, the permanent magnet 203 has an uneven thickness structure in which the thickness of the central portion 203m in the circumferential direction of the permanent magnet 203 is thicker in the radial direction than the both end portions 203t in the circumferential direction. . A portion where the thickness of the permanent magnet 203 changes in the circumferential direction is called an uneven thickness portion 203h. Furthermore, a plurality of grooves M extending in the axial direction are provided in the inner peripheral surface 203in of the permanent magnet 203. As shown in FIG.

According to the rotor 200 and the method of manufacturing the rotor 200 according to the second embodiment, the thickness of the permanent magnet 203 is set such that the central portion 203m in the circumferential direction is radially thicker than the both end portions 203t in the circumferential direction. By adopting a thick structure, the resin 4 is filled in the outer peripheral side of both circumferential ends of the permanent magnet 203 when integrally molded with the resin 4, so that the centrifugal force generated when the rotor 200 rotates can be counteracted and the rotor 200 can be made permanent. A magnet 203 can be held.

In addition, since the grooves M are provided on the inner peripheral surface of the permanent magnet 203, the grooves M of the permanent magnet 203 are filled with the resin 4, so that the resin 4 acts as an adhesive between the permanent magnet 203 and the outer core 2. Therefore, the permanent magnet 203 can be firmly held against the centrifugal force generated when the rotor 200 rotates.

In FIG. 11, the permanent magnet 203 has an uneven wall thickness structure, which is thinner at both ends 203t in the circumferential direction and thicker toward the central portion 203m in the circumferential direction. , the central portion in the axial direction may be of uneven thickness in the radial direction.

Further, in FIG. 11, a plurality of grooves M extending in the axial direction are provided in the inner peripheral surface of the permanent magnet 203, but a plurality of grooves extending in the radial direction and the circumferential direction may be provided.

Further, uneven thickness portion 203h and groove M of permanent magnet 203 may be subjected to the surface treatment shown in Embodiment 1, such as chemical etching or laser treatment, to improve adhesiveness.
Further, although the permanent magnet 203 has an uneven thickness structure and the groove M is provided on the inner peripheral surface, only the uneven thickness structure of the permanent magnet 203 may be employed, or only the groove M on the inner peripheral surface may be employed. .

Embodiment 3.
Hereinafter, a rotor 300 and a method of manufacturing the rotor 300 according to the third embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment.
In the first embodiment, as shown in FIG. 4, the outer and inner peripheral surfaces of the permanent magnets 3 in the cross section taken perpendicularly to the axial direction of the rotor 100 are arcuate. In addition, since the resin 4 does not exist on the outer peripheral side of the permanent magnet 3, the permanent magnet 3 cannot be pressed from the outer peripheral side to the inner peripheral side.

FIG. 12 is a schematic cross-sectional view of the rotor 300 according to Embodiment 3 taken perpendicularly to the axial direction. In the third embodiment, in order to strengthen the coercive force of the permanent magnet 3, the outer peripheral surface 302out of the outer core 302 is provided with a plurality of grooves M2 extending in the axial direction.

According to the rotor 300 and the method for manufacturing the rotor 300 according to the third embodiment,
By providing the grooves M2 on the outer peripheral surface of the outer core 302, the grooves M2 on the outer peripheral surface 302out of the outer core 302 are filled with the resin 4 when integrally molded with the resin 4. It plays a role of an adhesive between 302 and can hold the permanent magnet 3 firmly.

Furthermore, when the rotor 300 is integrally molded, the outer circumference of the outer core 302 , that is, the inner circumference of the permanent magnets 3 is filled with the resin 4 . is added. As a result, even if the permanent magnets 3 or the outer core 302 have dimensional variations, the variations are absorbed on the inner peripheral side of the permanent magnets 3, and the circularity of the outer peripheral surface of the rotor 300 can be increased.

13A and 13B are diagrams showing modifications of the grooves provided in the outer core 302, and the diagram on the left side is an enlarged view of the main part of the diagram on the right side.
12, the outer peripheral surface 302out of the outer core 302 is provided with the axially extending groove M2 filled with the resin 4. However, as shown in FIG. Circumferentially extending grooves M2b may be provided between the projections 21 of .

Further, the grooved portion of the permanent magnet 3 may be subjected to the surface treatment shown in Embodiment 1, such as chemical etching or laser treatment, to improve adhesiveness.

Embodiment 4.
Hereinafter, a rotor 400 and a method of manufacturing the rotor 400 according to the fourth embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment.
Rotor 100 of Embodiment 1 is integrally formed so that resin 4 surrounds shaft 1 . However, depending on the load, there is a concern that the strength between the shaft and the resin may be insufficient when the rotation speed of the rotor 100 is increased.

Therefore, in the fourth embodiment, the strength of the rotor 400 is increased by attaching the inner core 6 to the outer circumference of the shaft 1 .

FIG. 14 is a schematic cross-sectional view of the rotor 400 taken along a plane passing through its central axis.
FIG. 15 is a schematic cross-sectional view of the rotor 400 cut perpendicularly to the axial direction.

As shown in FIG. 15, the outer peripheral surface 1out of the shaft 1 and the inner peripheral surface 6in of the inner core 6 are in contact with each other. The outer peripheral surface 6out of the inner core 6 and the resin 4 are in contact with each other, and the resin 4 and the inner peripheral surface 2in of the outer core 2 are bonded together. , the inner diameter of the outer core 2 is larger than the outer diameter of the inner core 6 .

Iron, nickel, and cobalt, which are ferromagnetic materials, are generally used as the material of the inner core 6. However, since the magnetic flux in the inner core 6 is small, it does not have to be a ferromagnetic material. Also, the inner core 6 may be a laminated core or an integral core.

In addition, the inner core 6 may be surface-treated as necessary to improve adhesion with the resin 4 . Surface treatment methods include chemical etching, fine processing by laser processing, and grooving or knurling by mechanical processing.

Further, when the inner core 6 is assembled to the shaft 1, the inner core 6 is press-fitted to the shaft 1 for assembly. When integrally molding the rotor 400, the shaft 1 assembled with the inner core 6 is set in a mold, and the shaft 1 with the inner core 6, the outer core 2, and the permanent magnets 3 are integrally molded using the resin 4. The rotor 400 is thus manufactured.

According to the rotor 400 and the method of manufacturing the rotor 400 according to the fourth embodiment, the inner core 6 is attached to the outer peripheral surface 1out of the shaft 1, and the shaft 1 with the inner core 6, the outer core 2, and the permanent magnets 3 are assembled. The integral molding using the resin 4 provides a structure in which the inner core 6 is between the shaft 1 and the outer core 2, so the strength of the rotor 400 can be increased.

While this application describes various exemplary embodiments and examples, various features, aspects, and functions described in one or more embodiments may vary from particular embodiment to The embodiments are applicable singly or in various combinations without being limited to the application.
Therefore, countless modifications not illustrated are envisioned within the scope of the technology disclosed in the present application. For example, modification, addition or omission of at least one component, extraction of at least one component, and combination with components of other embodiments shall be included.

100, 100b, 100c, 200, 300, 400 rotors,
1, 1c shaft, 1out outer peripheral surface, 1s surface treatment portion, H hole,
2, 302 outer core, 2H center hole, 2down one end surface, 302out outer peripheral surface,
2in inner peripheral surface, 2out outer peripheral surface, 2s surface treatment portion, 21 protrusion,
3, 3b, 203 permanent magnet, 3down one end surface, 3in surface, 3s surface treatment portion,
203h uneven thickness portion, 203in inner peripheral surface, 203m central portion, 203t both ends,
4 resin, 50 lower mold, 51 spacer, 51a outer part, 51ain surface,
51aup upper end surface, 51b inner portion, 51bup upper end surface, 52 mold cavity,
53 shaft hole, 6 inner core, 6in inner peripheral surface, 6out outer peripheral surface,
M, M2, M2b grooves.

Claims (11)

a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A rotor comprising a resin that integrally molds a
A rotor in which the permanent magnet is subjected to microfabrication by chemical etching treatment for improving adhesiveness with the resin or laser treatment on at least one portion of the surface in contact with the resin. 2. The rotor according to claim 1, wherein the outermost peripheral surface of the rotor is the outer peripheral surface of the permanent magnet, and the resin is not formed outside the outer peripheral surface of the permanent magnet. The permanent magnet has an uneven thickness structure in which the thickness of the central portion in the circumferential direction is thicker in the radial direction than the thickness of both ends in the circumferential direction,
2. The rotor according to claim 1, wherein the outer peripheral surface of the resin filled on the outer peripheral side of the uneven thickness structure is flush with the outer peripheral surface of the magnet. 2. The rotor according to claim 1, wherein the rotor is integrally molded with the resin via an inner core made of a magnetic material, which is press-fitted to the outer peripheral surface of the shaft. 4. The shaft and the outer core according to any one of claims 1 to 3, wherein at least one portion of the surfaces of the shaft and the outer core that come into contact with the resin is subjected to a surface treatment or surface treatment for improving adhesion to the resin. rotor described in . 5. The rotor according to claim 4 , wherein at least one of the surfaces of the inner core and the outer core that come into contact with the resin is surface-treated or surface-treated to improve adhesion to the resin. 7. The rotor according to claim 5 , wherein said surface processing is grooving. The rotor according to any one of claims 1 to 7 , wherein the outer core has projections for positioning the permanent magnets at regular intervals in the circumferential direction. a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A rotor comprising a resin that integrally molds a
A rotor in which the shaft has a radially penetrating hole filled with the resin. a shaft;
a cylindrical outer core made of a magnetic material having an inner diameter larger than the outer diameter of the shaft;
a plurality of permanent magnets arranged on the outer peripheral surface of the outer core;
Between the outer peripheral surface of the shaft and the inner peripheral surface of the outer core, and between the axial end faces of the outer core and the axial end faces of the permanent magnet, the shaft, the outer core, and the permanent magnet A method of manufacturing a rotor comprising a resin integrally molding a
The shaft is inserted into and supported by the shaft hole provided in the center of the bottom surface of the lower mold having a mold hole hollowed out in a cylindrical shape of the mold,
a plurality of the permanent magnets arranged at equal intervals along the inner peripheral surface of the mold cavity; A component placement process in which the parts are supported by spacers so as to float from the bottom surface of the lower die;
and a resin press-fitting step of press-fitting the resin. In the component placement step,
The spacers are arranged at equal intervals along the inner peripheral surface of the mold cavity, and the cross section perpendicular to the circumferential direction of the spacers has a radially outer outer portion that is larger than a radially inner inner portion. The spacer has an L-shape protruding upward, the upper end face of the outer portion of the spacer is in contact with one end face of the permanent magnet 3 in the axial direction,
11. The method of manufacturing a rotor according to claim 10 , wherein the upper end surface of the inner portion of the spacer contacts one axial end surface of the outer core.

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