Rotor

Abstract

A rotor according to the present disclosure is provided with: a rotor core rotatable about a rotation axis; a plurality of magnets provided in the rotor core; a pair of end plates provided on both axial end sides of the rotor core, each of the end plates having a first surface located on the rotor core side and a second surface located on the opposite side to the first surface; and a resin part having a first resin part covering at least the outer peripheral edge of the second surface of the one end plate, a second resin part covering at least the outer peripheral edge of the second surface of the other end plate, and a third resin part connecting the first resin part and the second resin part on the outside of the rotor core. The second surface of at least one of the pair of end plates is provided with a resin insertion part into which the resin part enters.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a rotor provided in an electric motor or the like. BACKGROUND

[0002] Conventionally, a rotor of an electric motor is provided with a rotor core provided on a shaft so as to be integrally rotatable, a plurality of permanent magnets provided on the rotor core, and a pair of plate-shaped end plates provided on both axial end sides of the rotor core. In the rotor of such a structure, there is a case where the rotor core and the pair of end plates are molded with resin in order to increase the strength of the rotor and to secure a sufficient distance between the permanent magnets of the rotor and a member affected by the magnetic force of the permanent magnets.

[0003] The rotor of the electric motor is provided with a resin portion composed of resin that is molded. The resin portion has a first resin portion that covers a surface of one end plate of the pair of end plates, a second resin portion that covers a surface of the other end plate of the pair of end plates, and a third resin portion that connects the first resin portion and the second resin portion together on the outside of the rotor core.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Application Publication No. 2008-199725 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] For the first resin portion, a sufficient thickness is required in order to secure a sufficient distance between the permanent magnets and a member affected by the permanent magnets. However, in the case where the first resin portion has a sufficient thickness, the weight of the first resin portion becomes large. There is a concern that, if the weight of the first resin portion is large, the third resin portion is broken due to centrifugal force applied to the first resin portion when the electric motor is rotated at high speed, and the first resin portion is peeled off from the end plate. There is a concern that, similarly to the first resin portion, the second resin portion is also peeled off from the end plate.

[0009] Therefore, in order not to break the third resin portion, it is considered to use resin having a sufficient strength. However, there is a concern that, in the case where the resin portion has a sufficient strength, a crack is generated in the resin portion due to a difference between the expansion coefficient of a ferrous portion of the electric motor and the expansion coefficient of the resin portion when the electric motor is rotated at high speed and becomes high temperature.

[0010] In order to solve the above-described problems, it is desirable to provide a rotor provided with a resin portion composed of resin that is molded, in which the resin portion is not easily broken when the rotor is rotated.

[0011] SOLUTION TO PROBLEM

[0012] For the rotor of the present disclosure, there are provided: a rotor core rotatable about a rotational axis; a plurality of magnets provided to the rotor core; a pair of end plates provided to both axial ends of the rotor core, each having a first surface on the rotor core side and a second surface on the opposite side of the first surface; and a resin portion having a first resin portion covering at least an outer periphery of the second surface of one of the end plates, a second resin portion covering at least an outer periphery of the second surface of the other end plate, and a third resin portion connecting the first resin portion and the second resin portion together outside the rotor core. The resin insertion portion for the resin portion is provided to the second surface of at least one of the pair of end plates. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a schematic perspective view of a rotor of Embodiment 1 of the present application.

[0014] Figure 2 is a schematic longitudinal sectional view of the rotor of Embodiment 1 of the present application, which is shown partially omitted.

[0015] Figure 3 is a schematic perspective view of a resin portion of the rotor of Embodiment 1 of the present application.

[0016] Figure 4 is a schematic perspective view of the rotor of Embodiment 1 of the present application, which is shown partially enlarged, with the resin portion omitted, and with a portion shown in cross section.

[0017] Figure 5 is a schematic perspective view of the rotor of Embodiment 1 of the present application, which is shown partially enlarged, with a portion shown in cross section.

[0018] Figure 6 is a schematic transverse sectional view of the rotor of Embodiment 1 of the present application, which is shown partially enlarged.

[0019] Figure 7 is an explanatory view showing an example in which the position of a screw is arranged radially inward of a rotor core, as compared to the case of Embodiment 1 of the present application.

[0020] Figure 8 is an explanatory view showing an example in which the position of a screw is arranged radially inward of a rotor core, as compared to the case of Embodiment 1 of the present application. Figure 7

[0021] Figure 9 ​This is a schematic perspective view showing a portion of the rotor of the second embodiment of the present invention, with the resin portion omitted and the portion shown in cross-section.

[0022] Figure 10 This is a schematic perspective view showing a portion of the rotor of the second embodiment of the present invention, enlarged and shown in cross-section.

[0023] Figure 11 This is a schematic longitudinal sectional view of the rotor according to the second embodiment of the present invention, with details omitted.

[0024] Figure 12 This is a schematic perspective view showing a partial enlarged view of a modified example 1 of the rotor of the present invention, with the resin portion omitted and the portion shown in cross-section.

[0025] Figure 13 This is a schematic perspective view showing a partial enlarged view of a modified example 2 of the rotor of the present invention, with the resin portion omitted and the portion shown in cross-section.

[0026] Figure 14 This is a schematic perspective view showing a partial enlarged view of a modified example 3 of the rotor of the present invention, with the resin portion omitted and the portion shown in cross-section. Detailed Implementation

[0027] The rotor of one embodiment of this disclosure will now be described with reference to the accompanying drawings. Figures 1-5 The rotor 1 of the first embodiment will be described. The rotor 1 is used together with a stator (not shown) in an electric motor that supplies power to a rotating device. The rotor 1 includes a rotor core 2, a plurality of magnets 3, a pair of end plates 4 and 5, a mounting member 6, and a resin part 7. Furthermore, the device using the rotor 1 is not limited to an electric motor; for example, it may also be a generator.

[0028] The rotor core 2 is a cylindrical shape with openings at both ends along the axial direction J1, and is made of a magnetic material. Typically, the rotor core 2 has a structure with multiple electromagnetic steel plates (not shown). The multiple electromagnetic steel plates overlap each other along the axial direction J1. In the first embodiment, the rotor core 2 has an annular portion 8 and multiple protrusions 9. The annular portion 8 is a cylindrical shape extending along the axial direction J1, with openings at both ends along the axial direction J1. Multiple protrusions 9 are provided on the annular portion 8, protruding outwards radially K1. Each protrusion 9 is plate-shaped along the axial direction J1 of the annular portion 8, protruding outwards radially K1 from the outer periphery of the annular portion 8. The multiple protrusions 9 are arranged in a circumferential arrangement of the annular portion 8 at intervals. A groove 10 is formed between adjacent protrusions 9, 9, opening outwards radially K1 from the outer side of the annular portion 8. In the axial direction J1, both ends of the groove 10 open outwards from the outer side of the rotor core 2. Figure 2As shown, each protrusion 9 has a plurality of circular through-holes 11 extending through in the axial direction J1. The plurality of through-holes 11 are arranged in the circumferential direction of the rotor core 2.

[0029] The rotor core 2 is rotatable about a rotation axis (rotational shaft) 28 as a center. The rotation axis 28 is cylindrical and extends in the axial direction J1. The rotation axis 28 is provided in the housing of an unillustrated motor in a rotatable manner via an unillustrated bearing. The rotation axis 28 is rotatable about its own axis. The rotation axis 28 is provided integrally with the rotor core 2. Specifically, the rotor core 2 is fixed to the rotation axis 28 in a manner rotatable integrally with the rotation axis 28 in a state where the rotation axis 28 penetrates the inner hole 12 of the rotor core 2.

[0030] Each magnet 3 is a substantially rectangular plate. A plurality of magnets 3 are provided in the slot portions 10 formed in the rotor core 2. Specifically, the magnets 3 are provided in the slot portions 10 in a state where one plate surface of the magnet 3 opposes one side surface of the slot portion 10 and another plate surface of the magnet 3 opposes another side surface of the slot portion 10. That is, the magnets 3 are positioned in the slot portions 10 in a state extending in the axial direction J1 and in a state extending in the radial direction K1 of the rotor core 2. In a state where the magnets 3 are provided in the slot portions 10, the magnets 3 are in contact with the bottom surface of the slot portions 10. In this way, the plurality of magnets 3 are provided in the rotor core 2 in a radial manner.

[0031] In the axial direction J1, the length of the magnet 3 and the length of the axial direction J1 of the slot portion 10 are substantially the same. Thus, the magnet 3 does not protrude from both ends in the axial direction J1 of the slot portion 10 in a state where the magnet 3 is provided in the slot portion 10. The magnet 3 is exposed from the slot portion 10 in the axial direction J1. In the radial direction K1 of the rotor core 2, the length of the magnet 3 is smaller than the depth of the slot portion 10. Thus, in a state where the magnet 3 is provided in the slot portion 10, a recessed portion 13 is formed in the rotor core 2 in a groove shape extending in the axial direction J1. The recessed portion 13 has opposing surfaces of adjacent protrusions 9, 9 as side surfaces and an end surface of the magnet 3 provided in the slot portion 10 as a bottom surface. The recessed portion 13 is open to the outside in the radial direction K1 of the rotor core 2. In this way, the plurality of magnets 3 are provided in the rotor core 2.

[0032] A pair of end plates 4 and 5 are provided at both ends of the rotor core 2 along the axial direction J1. Each pair of end plates 4 and 5 has a first surface 14 located on the side of the rotor core 2 and a second surface 15 located on the side opposite to the first surface 14. In the first embodiment, the pair of end plates 4 and 5 are circular plates. When the end plates 4 and 5 are circular plates, the first surface 14 is one surface of the circular plate end plates 4 and 5, and the second surface 15 is the other surface of the circular plate end plates 4 and 5. The circular plate end plates 4 and 5 have a circular through hole 16 extending along the axial direction J1 at their central portion. The aforementioned rotating shaft 28 passes through this through hole 16. The circular plate end plates 4 and 5 have a plurality of through holes 17 extending along the axial direction J1. The plurality of through holes 17 are arranged circumferentially on the end plates 4 and 5. The outer diameter of the circular plate end plates 4 and 5 is smaller than the outer diameter of the rotor core 2. A plurality of resin insertion portions 18 are provided on the second surface 15 of one end plate 4 and the second surface 15 of the other end plate 5 for the resin portion 7 to enter. The plurality of resin insertion portions 18 are arranged in a circumferential arrangement on the end plates 4 and 5. In the first embodiment, the resin insertion portion 18 is a circular concave shape recessed toward the first surface 14.

[0033] Mounting member 6 is in the shape of a circular plate. Mounting member 6 has a circular through hole 19 extending axially along J1 at its center. Mounting member 6 has multiple threaded holes 20 extending axially along J1. The multiple threaded holes 20 are arranged circumferentially on the mounting member 6. Internal threads are formed on the inner circumferential surface of each threaded hole 20. The outer diameter of the circular plate-shaped mounting member 6 is smaller than the outer diameter of the end plates 4 and 5.

[0034] like Figure 2 As shown, a pair of end plates 4 and 5 are fixed to the rotor core 2 using a plurality of screws 21. Specifically, with the first surface 14 of one end plate 4 abutting against one end face of the rotor core 2 along the axial direction J1, and the first surface 14 of the other end plate 5 abutting against the other end face of the rotor core 2 along the axial direction J1, screws 21 are screwed into the threaded holes 20 of the mounting member 6, which overlaps with the second surface 15 of one end plate 4, through the through holes 17 of the pair of end plates 4 and 5 and the through holes 11 of the rotor core 2. Thus, the pair of end plates 4 and 5 are fixed to both ends of the rotor core 2 along the axial direction J1. With the pair of end plates 4 and 5 fixed to the rotor core 2, the rotating shaft 28 that fixes the rotor core 2 passes through the inner hole 12 of the rotor core 2, the through holes 16 of the end plates 4 and 5, and the through holes 19 of the mounting member 6. As described above, the outer diameter of the end plates 4 and 5 is smaller than the outer diameter of the rotor core 2 and larger than the outer diameter of the mounting member 6. Therefore, with a pair of end plates 4 and 5 fixed to the rotor core 2, the outer periphery of the two end faces of the rotor core 2 along the axial direction J1, and the outer periphery of the second face 15 of the end plate 4 are exposed to the outside.

[0035] The resin portion 7 has a first resin portion 22, a second resin portion 23, and a third resin portion 24. The first resin portion 22 is disposed on the one end side of the axial direction Jl of the rotor core 2 in a manner to cover at least the outer periphery of the second face 15 of the one end plate 4. In the first embodiment, the first resin portion 22 is substantially circular plate-shaped, and is disposed on the one end side of the axial direction Jl of the rotor core 2 in a manner to cover the outer periphery of the second face 15 of the one end plate 4, the outer periphery of the second face 15 of the one end plate 4, the outer periphery of the second face 15 of the other end plate 5, and the outer periphery of the second face 15 of the other end plate 5. The second resin portion 23 is disposed on the other end side of the axial direction Jl of the rotor core 2 in a manner to cover at least the outer periphery of the second face 15 of the other end plate 5. In the first embodiment, the second resin portion 23 is substantially circular plate-shaped, and is disposed on the other end side of the axial direction Jl of the rotor core 2 in a manner to cover the second face 15 of the other end plate 5, the outer periphery of the second face 15 of the other end plate 5, and the outer periphery of the second face 15 of the other end plate 5. The second resin portion 23 covers the second face 15 of the other end plate 5 leaving the inner periphery of the second face 15 of the other end plate 5. The third resin portion 24 is disposed on the outside of the rotor core 2 in a manner to connect the first resin portion 22 and the second resin portion 23 together. In the first embodiment, the third resin portion 24 is substantially rod-shaped, and is disposed on the rotor core 2 in a manner to fill the recessed portion 13 of the rotor core 2.

[0036] The resin portion 7 is composed of resin. Typically, the resin portion 7 is formed, for example, by insert molding. Specifically, after molten resin is flowed into a mold in which the rotor core 2 provided with the pair of end plates 4, 5 and the plurality of magnets 3 is accommodated, the resin is solidified, whereby the resin portion 7 is formed in the rotor core 2 provided with the pair of end plates 4, 5 and the plurality of magnets 3. As shown in FIG. 1, the resin portion 7 covers the head of the screw 21 protruding from the other end plate 5. Figure 2 As shown in FIG. 1, the resin portion 7 covers the head of the screw 21 protruding from the other end plate 5. Figure 5 As shown in FIG. 1, in the radial direction Kl of the rotor core 2, the protruding portion 9 protrudes more than the resin portion 7.

[0037] In such molding of the rotor core 2 with resin, for the resin portion 7, after molten resin is flowed into the resin insertion portion 18, the resin flowed into the resin insertion portion 18 is solidified, whereby the resin insertion portion 18 is entered. Here, if a portion of the resin portion 7 in which the resin insertion portion 18 is entered is provided as an engaging portion 25, the engaging portion 25 is inserted and engaged in the resin insertion portion 18. In the first embodiment, a plurality of engaging portions 25 is provided in the first resin portion 22. The plurality of engaging portions 25 is disposed in alignment in the circumferential direction of the first resin portion 22. Also in the first embodiment, a plurality of engaging portions 25 is provided in the second resin portion 23. The plurality of engaging portions 25 is disposed in alignment in the circumferential direction of the second resin portion 23.

[0038] When the rotor core 2 is molded using resin, the first resin portion 22 is generally cylindrical and arranged to surround the outer side of the mounting member 6. Centrifugal force is applied to the first resin portion 22 by rotating the rotor 1. If the axial thickness J1 of the first resin portion 22 is large and the radial thickness K1 of the first resin portion 22 is small, then when centrifugal force is applied to the first resin portion 22, the first resin portion 22 is prone to deform outward in the radial direction K1. Conversely, if the axial thickness J1 of the first resin portion 22 is small and the radial thickness K1 of the first resin portion 22 is large, then when centrifugal force is applied to the first resin portion 22, the first resin portion 22 is less prone to deform outward in the radial direction K1. This relationship exists when the first resin portion 22 is generally cylindrical.

[0039] like Figure 2 As shown, because the mounting member 6 is provided on the rotor core 2, the radial thickness K1 of the first resin part 22 cannot be increased. Therefore, based on the above-mentioned relationship, the first resin part 22 is prone to deforming outward in the radial direction K1. If the first resin part 22 is prone to deformation and the end plates 4 and 5 do not have resin insertion portions 18, the third resin part 24 is prone to breakage due to the centrifugal force applied to the first resin part 22 when the rotor 1 rotates at high speed. There is a concern that if the third resin part 24 breaks, the first resin part 22 will peel off from the rotor core 2.

[0040] As described above, the reason why the radial thickness K1 of the first resin part 22 cannot be increased is because the mounting member 6 protrudes outward in the radial direction K1. The reason the mounting member 6 protrudes outward in the radial direction K1 is due to the position of the threaded hole 20 of the mounting member 6. That is, the reason the mounting member 6 protrudes outward in the radial direction K1 is due to the position of the screw 21 provided on the rotor 1. Regarding this, using... Figures 6-8 Please provide an explanation.

[0041] The screw 21 located on rotor 1 serves to overcome the centrifugal force applied to rotor core 2 and magnet 3 when rotor 1 rotates. Figure 6 As shown, in the rotor 1 of the first embodiment, multiple electromagnetic steel plates are fixed by screws 21 that pass through the rotor core 2 along the axial direction J1 between adjacent magnets 3, 3. The screws 21 are located on the outer side of the rotor core 2 in the radial direction K1 between adjacent magnets 3, 3. The area between the screws 21 and the magnets 3 forms a weaker part 29 of the rotor core 2. Figure 6The portion 30 surrounded by the double-dotted line becomes a portion that assists the centrifugal force applied to the weak strength portion 29 of the rotor core 2. In the first embodiment, the through-hole 31 is formed in the inner edge portion of the rotor core 2 along the axial direction J1. Thereby, the short circuit of the magnetic flux can be suppressed. In the case where the through-hole 31 is not formed, the short circuit of the magnetic flux occurs, the magnetic flux that assists the torque decreases, and thus the torque decreases. That is, the performance of the motor decreases.

[0042] Figure 7 An example in which the position of the screw 21 is arranged inside the radial direction K1 compared to the case of the first embodiment is shown. In the structure shown in Figure 7 The structure shown in Figure 6 The weak strength portion 29 of the rotor core 2 is thinner in the structure shown in Figure 7 The structure shown in Figure 6 The portion 30 that assists the centrifugal force applied to the weak strength portion 29 of the rotor core 2 is larger in the structure shown in Figure 7 The rotor core 2 is easily broken when the rotor 1 rotates in the structure shown in Figure 7 The durability of the rotor 1 with respect to high-speed rotation is lower in the structure shown in

[0043] Figure 8 An example in which the position of the screw 21 is arranged inside the radial direction K1 compared to the case of the first embodiment is shown. In the structure shown in Figure 7 The screw 21 is arranged at a position inside the radial direction K1 from the magnet 3 in the structure shown in Figure 8 The screw 21 is typically arranged in the inner edge portion of the rotor core 2. In the structure shown in Figure 8 The structure shown in Figure 7 The portion 30 that assists the centrifugal force applied to the weak strength portion 29 of the rotor core 2 is larger in the structure shown in Figure 8 The structure is a structure in which the weak strength portion 29 of the rotor core 2 bears substantially all of the centrifugal force applied to the rotor core 2 and the magnet 3. In the structure shown in Figure 8 The weak strength portion 29 of the rotor core 2 becomes thinner in the structure shown in Figure 7 The structure than in the case of the structure shown in Figure 8 The structure shown in Figure 6 The rotor core 2 is easily broken when the rotor 1 rotates in the structure shown in Figure 7 The structure shown in Figure 8 The durability of the rotor 1 with respect to high-speed rotation is lower in the structure shown in

[0044] According to the above, in order to provide the rotor 1 that can withstand high-speed rotation, it is preferable that the screw 21 be disposed at a further outer side in the radial direction K1 of the rotor core 2. In the rotor 1, the more the screw 21 is disposed at a further outer side, the smaller the force applied to the rotor core 2 itself becomes. Thus, the rotor 1 of the first embodiment is a structure that can withstand high-speed rotation. Furthermore, the more the screw 21 is located at the outer side, the greater the fixing strength of the torque (reaction of the torque) in the circumferential direction of the rotor 1 based on the screw 21 becomes. Thus, in general, there is a demand to dispose the screw 21 at the outer side when designing the motor.

[0045] In the case where the rotor core 2 is molded with resin, in order to avoid the influence of the magnets 3 on the members provided in the vicinity of the first resin portion 22, the first resin portion 22 has a sufficient thickness in the axial direction J1. For example, the thickness of the first resin portion 22 can be about 10 mm. In the case where the first resin portion 22 has a sufficient thickness, the first resin portion 22 becomes heavy. There is a concern that, in the case where the resin insertion portion 18 is not provided to the end plates 4, 5, if the first resin portion 22 is heavy, the third resin portion 24 is broken by the centrifugal force applied to the first resin portion 22 when the rotor 1 rotates at high speed, and the first resin portion 22 is peeled from the rotor core 2. In particular, in the case where the third resin portion 24 is an elongated rod shape as in the illustrated example, the third resin portion 24 is easily broken by the centrifugal force applied to the first resin portion 22. Furthermore, there is a concern that, in the case where the resin insertion portion 18 is not provided to the end plates 4, 5, the second resin portion 23 is peeled from the rotor core 2 as with the first resin portion 22.

[0046] In the case of the rotor 1 of the first embodiment, the resin portion 7 has the engagement portion 25 that engages with the resin insertion portion 18 formed in the end plates 4, 5. Thereby, when the rotor 1 rotates at high speed, the third resin portion 24 is not easily broken by the centrifugal force applied to the first resin portion 22 and the second resin portion 23. Thus, according to the rotor 1 of the first embodiment, the resin portion 7 is not easily broken when the rotor 1 rotates.

[0047] Next, the rotor 1a of the second embodiment of the present application will be described using Figures 9-11 The rotor 1a of the second embodiment of the present application will be described. Furthermore, there is a case where, for the constituent members having the same reference numerals as those labeled in the first embodiment, the same action is provided, and thus the description will be omitted below. In the rotor 1a of the second embodiment, a pair of end plates 4, 5 is different from that of the first embodiment.

[0048] In the first embodiment, the resin insertion portion 18 is provided in a recessed shape, but in the second embodiment, the resin insertion portion 18 is a through-hole that penetrates the end plates 4, 5 in the axial direction J1. The resin insertion portion 18 is, for example, a circular through-hole. In the case where the resin insertion portion 18 is a circular through-hole, it is possible to suppress the cost taken to form the resin insertion portion 18. The resin insertion portion 18 is disposed in correspondence with the magnets 3 provided to the rotor core 2 in the axial direction J1. Therefore, the pair of end plates 4, 5 is fixed to the rotor core 2 in a manner that the slot portions 10 of the rotor core 2 and the resin insertion portions 18 correspond in the axial direction J1.

[0049] As described above, the magnets 3 disposed to the slot portions 10 of the rotor core 2 have exposed portions 26 that are exposed from the rotor core 2 in the axial direction J1 of the rotor core 2. As shown in FIG. 6, the resin insertion portion 18 is disposed at a position that corresponds to the exposed portions 26 of the magnets 3 in the axial direction J1 of the rotor core 2. The exposed portions 26 are exposed to the outside of the rotor core 2 via the resin insertion portion 18 that is a through-hole in a state where the resin portion 7 is not formed. Figure 9

[0050] In the second embodiment, the magnets 3 are provided with a covering portion 27 that covers the outer surfaces thereof. The covering portion 27 is composed of resin. In the case where the covering portion 27 is made of resin, the magnets 3 are fixed to the rotor core 2 by the covering portion 27.

[0051] In the case where the resin insertion portion 18 is a through-hole, the engaging portion 25 of the resin portion 7 reaches the covering portion 27 of the magnet 3 by penetrating the resin insertion portion 18. As described above, the engaging portion 25 is formed by causing molten resin to flow into the resin insertion portion 18 when the rotor core 2 is molded with resin, and then solidifying the resin inside the resin insertion portion 18. Thus, the engaging portion 25 is combined with the covering portion 27 of the magnet 3. Further, the covering portion 27 and the resin portion 7 are composed of, for example, epoxy resin. The covering portion 27 and the resin portion 7 are not limited to the case where they are composed of epoxy resin, but can be composed of the same kind of resin.

[0052] In the case where the resin insertion portion 18 is a through-hole, the magnet 3 can be fixed to the rotor core 2 when the rotor core 2 is molded with resin. When the rotor core 2 is molded with resin, molten resin is caused to flow into a mold that accommodates the rotor core 2 provided with the pair of end plates 4, 5 and the plurality of magnets 3. When the molten resin flows into the mold, the molten resin enters the gap between the magnet 3 and the protruding portion 9 through the resin insertion portion 18 of the end plate 4, 5. Then, the magnet 3 is fixed to the rotor core 2 by solidifying the resin that has entered between the magnet 3 and the protruding portion 9. Thus, the covering portion 27 that covers the outer surface of the magnet 3 is formed.

[0053] ​When the molten resin flows into the mold, the molten resin fills in the resin insertion portion 18 as a through-hole resin insertion portion, and enters between the magnet 3 and the protruding portion 9 through the resin insertion portion 18. That is, the resin inside the resin insertion portion 18, and the resin between the magnet 3 and the protruding portion 9 are continuous. Then, after the molten resin flows into the mold, the resin inside the mold is solidified, whereby the first resin portion 22 arranged on the one end plate 4 side, the second resin portion 23 arranged on the other end plate 5 side, the third resin portion 24 connecting the first resin portion 22 and the second resin portion 23 together, the engagement portion 25 engaged with the resin insertion portion 18, and the covering portion 27 fixing the magnet 3 to the rotor core 2 are integrally formed. The covering portion 27 is integrally formed with the engagement portion 25 by flowing the molten resin into the resin insertion portion 18 and around the magnet 3 through the resin insertion portion 18 when the rotor core 2 is molded with resin, and then solidifying the resin inside the resin insertion portion 18 and the resin flowed around the magnet 3.

[0054] In the case of the rotor la of the second embodiment, the engagement portion 25 is combined with the covering portion 27 covering the outer surface of the magnet 3. The engagement portion 25 and the covering portion 27 are composed of an epoxy resin. Thus, according to the rotor la of the second embodiment, the engagement portion 25 can be firmly combined with the magnet 3, and thus the engagement portion 25 can be stably engaged with the resin insertion portion 18.

[0055] In the case of the rotor la of the second embodiment, the magnet 3 is fixed to the rotor core 2 when the rotor core 2 is molded with resin. According to the rotor la of the second embodiment, the flow path of the resin flowed around the magnet 3 can be ensured by the resin insertion portion 18 with which the engagement portion 25 is engaged, and thus the cost taken for the work of forming the covering portion 27 can be reduced.

[0056] According to at least one embodiment described above, the resin portion 7 composed of the resin with which the rotor core 2 is molded enters the resin insertion portion 18 of the end plate 4, 5. Thus, a rotor 1, la can be provided which has a resin portion 7 composed of the resin with which molding is performed, in which the resin portion 7 is less likely to be broken when the rotor 1, la rotates.

[0057] The present disclosure has been described in detail, but the present disclosure is not limited to each of the embodiments described above. These embodiments can be variously added, replaced, changed, partially deleted, or the like within a range not departing from the gist of the present disclosure, or within a range not departing from the gist of the present disclosure extended from the content described in the claims and equivalents thereof. In addition, these embodiments can also be implemented in combination. For example, in the embodiments described above, the order of each operation, the order of each process is shown as an example, and is not limited to the order of each operation, the order of each process. In addition, the same applies to the case where numerical values or mathematical expressions are used in the description of the embodiments described above.

[0058] For example, the structure of the resin insertion portion 18 can also be Figure 12 the structure shown in FIG. 6, Figure 13 the structure shown in FIG. 7, or Figure 14 the structure shown in FIG. 8. In Figure 12 the case of the rotor lb of Modification Example 1 shown in FIG. 6, a circular ring-shaped resin insertion portion 18 is provided on the second face 15 of the one end plate 4. The circular ring-shaped resin insertion portion 18 is arranged concentrically with the one end plate 4. The circular ring-shaped resin insertion portion 18 is a groove shape that is recessed toward the first face 14 side. In Figure 13 the case of the rotor lc of Modification Example 2 shown in FIG. 7, a plurality of substantially circular arc-shaped resin insertion portions 18 are provided on the second face 15 of the one end plate 4. The plurality of substantially circular arc-shaped resin insertion portions 18 are arranged on the same circle. Each of the substantially circular arc-shaped resin insertion portions 18 is a through-hole that penetrates in the axial direction Jl. In this case, the resin insertion portions 18 are arranged at positions corresponding to the magnets 3 in the axial direction Jl. In Figure 14 the case of the rotor Id of Modification Example 3 shown in FIG. 8, a plurality of substantially rectangular-shaped resin insertion portions 18 that extend along the radial direction Kl of the one end plate 4 are provided on the second face 15 of the one end plate 4. The plurality of substantially rectangular-shaped resin insertion portions 18 are arranged radially. Each of the substantially rectangular-shaped resin insertion portions 18 is a through-hole that penetrates in the axial direction Jl. In this case, the resin insertion portions 18 are arranged at positions corresponding to the magnets 3 in the axial direction Jl. Further, in Figure 12 the rotor lb of Modification Example 1 shown in FIG. 6, Figure 13 the rotor lc of Modification Example 2 shown in FIG. 7, and Figure 14 the rotor Id of Modification Example 3 shown in FIG. 8, the other end plate 5 is the same structure as the other end plate 5 used in the rotor la of the second embodiment. In Figure 12 the rotor lb of Modification Example 1 shown in FIG. 6, Figure 13 the rotor lc of Modification Example 2 shown in FIG. 7, and Figure 14 the rotor Id of Modification Example 3 shown in FIG. 8, the other end plate 5 can also be the same structure as the one end plate 4. In the rotor lb of Modification Example 1, the rotor lc of Modification Example 2, and the rotor Id of Modification Example 3, the other structures are the same as the rotor 1 of the first embodiment and the rotor la of the second embodiment.

[0059] The rotor of the rotor 1, 1a of each of the embodiments and the rotor of the rotor lb, lc, Id of each of the modifications can be either a rotor of an SPM (Surface Permanent Magnet) motor or a rotor of an IPM (Interior Permanent Magnet) motor.

[0060] In the rotors 1 and 1a of the various embodiments and the rotors 1b, 1c and 1d of the various modified examples, the resin insertion part 18 is provided on the second surface 15 of the two end plates 4 and 5 of the pair of end plates 4 and 5, but it may also be provided on either of the pair of end plates 4 and 5. That is, the resin insertion part 18 only needs to be provided on the second surface 15 of at least one of the pair of end plates 4 and 5.

[0061] Regarding the above-described embodiments, the following notes are further disclosed.

[0062] (Note 1)

[0063] The rotor (1) comprises: a rotor core (2) capable of rotating about a rotation axis (28) as the center of rotation; a plurality of magnets (3) disposed on the rotor core (2); a pair of end plates (4, 5) disposed on both axial ends of the rotor core (2), each having a first surface (14) on the side of the rotor core (2) and a second surface (15) on the side opposite to the first surface (14); and a resin portion. (7) has a first resin portion (22), a second resin portion (23), and a third resin portion (24). The first resin portion (22) covers at least the outer periphery of the second surface (15) of one end plate (4), the second resin portion (23) covers at least the outer periphery of the second surface (15) of the other end plate (5), and the third resin portion (24) connects the first resin portion (22) and the second resin portion (23) together on the outside of the rotor core (2). A resin insertion portion (18) for the resin portion (7) to enter is provided on the second surface (15) of at least one of the pair of end plates (4, 5).

[0064] (Note 2)

[0065] For the rotor (1), preferably, as noted in Appendix 1, the resin insertion part (18) is a through hole through the end plates (4, 5), the magnet (3) has an exposed part (26) exposed from the rotor core (2) in the axial direction, and the resin insertion part (18) is disposed at a position corresponding to the exposed part (26) in the axial direction of the rotor core (2).

[0066] (Note 3)

[0067] For the rotor (1), preferably, as noted in Appendix 2, the magnet (3) has a covering portion (27) covering its outer surface, the covering portion (27) and the resin portion (7) being made of epoxy resin.

[0068] (Note 4)

[0069] For the rotor (1), it is preferable that, in any one of the following Notes 1 to 3, the resin insertion portion (18) is provided to the second face (15) of both of the pair of end plates (4, 5).

[0070] (Note 5)

[0071] For the rotor (1), it is preferable that, in any one of the following Notes 1 to 4, the rotor core (2) has a plurality of electromagnetic steel sheets that overlap each other in the axial direction of the rotation axis (28), the plurality of magnets (3) are provided to the rotor core (2) in a radial manner, and the plurality of electromagnetic steel sheets are fixed by a screw (21) that penetrates the rotor core (2) between adjacent magnets (3, 3).

[0072] Explanation of Reference Numerals

[0073] 1, rotor; 2, rotor core; 3, magnet; 4, end plate; 5, end plate; 7, resin portion; 14, first face; 15, second face; 18, resin insertion portion; 21, screw; 22, first resin portion; 23, second resin portion; 24, third resin portion; 26, exposed portion; 27, covered portion; 28, rotation axis.

Claims

1. A rotor, wherein the rotor is provided with: a rotor core that is rotatable about a rotational axis as a center of rotation; a plurality of magnets provided to the rotor core; a pair of end plates provided to both axial ends of the rotor core, each of which has a first surface on the rotor core side and a second surface on the opposite side from the first surface; and a resin portion having a first resin portion that covers at least an outer periphery of the second surface of one of the end plates, a second resin portion that covers at least an outer periphery of the second surface of the other end plate, and a third resin portion that connects the first resin portion and the second resin portion together on the outside of the rotor core, a resin insertion portion through which the resin portion enters is provided to the second surface of at least one of the pair of end plates.

2. The rotor according to claim 1, wherein the resin insertion portion is a through hole that penetrates the end plate, the magnet has an exposed portion that is exposed from the rotor core in the axial direction of the rotor core, the resin insertion portion is disposed at a position corresponding to the exposed portion in the axial direction of the rotor core.

3. The rotor according to claim 2, wherein the magnet is provided with a covering portion that covers an outer surface thereof, the covering portion and the resin portion are composed of an epoxy resin.

4. The rotor according to any one of claims 1 to 3, wherein the resin insertion portion is provided to the second surface of both of the pair of end plates.

5. The rotor according to any one of claims 1 to 4, wherein the rotor core has a plurality of electromagnetic steel sheets that overlap each other in the axial direction of the rotational axis, the plurality of magnets are provided to the rotor core in a radial manner, the plurality of electromagnetic steel sheets are fixed by a screw that penetrates the rotor core between adjacent magnets.

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