Rotor and manufacturing method of rotor

Abstract

To provide a rotor capable of suppressing deformation of a bridge part and a manufacturing method of the rotor.SOLUTION: A rotor 10 has a rotor core 11, a magnet 30 accommodated in a magnet housing hole 20, and resin material 40 fixing the magnet 30 with respect to the rotor core 11. The rotor core 11 has a peripheral part 13, an inner peripheral part 14, and a bridge part 15 positioned between two adjacent magnet housing holes 20 in a circumferential direction of the rotor core 11 and connecting the peripheral part 13 and the inner peripheral part 14. An inner surface of the magnet housing hole 20 includes a first surface 21 composing the peripheral part 13 and a second surface 22 composing the inner peripheral part 14. Inside the magnet housing hole 20, a projection 24 is provided blocking a space between the second surface 22 and a second outer surface 32 of the magnet 30 from both sides in an orthogonal direction. The first surface 21 contacts a first outer surface 31 of the magnet 30. The resin material 40 is filled in a part of both sides in the orthogonal direction of the magnet 30 in the magnet housing hole 20.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a rotor and a method for manufacturing a rotor. [Background technology]

[0002] The rotating electric machine includes a cylindrical stator and a rotor that rotates inside the stator. Patent Document 1 discloses a rotor for use in a magnet-embedded rotating electric machine. This rotor includes a cylindrical rotor core with multiple magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material that fills the magnet accommodating holes and fixes the magnets to the rotor core.

[0003] The magnet accommodating holes are formed at intervals in the circumferential direction of the rotor core. Two circumferentially adjacent magnet accommodating holes extend in a V-shape so as to approach each other in the circumferential direction toward the radially inner portion. A thin-walled bridge portion is formed between the radially inner ends of the two magnet accommodating holes of the rotor core.

[0004] The resin material is filled inside the magnet receiving hole around the entire outer surface of the magnet. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-119766 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the rotor described in Patent Document 1, when the magnet accommodating hole is filled with the resin material using an injection device, the pressure of the resin material acts on the entire inner surface of the magnet accommodating hole. At this time, the force based on the pressure of the resin material acts toward the outer periphery of the rotor core. This may cause the bridge portion to deform, which may cause the outer periphery of the rotor core to deform. In this case, there is a risk that the air gap between the rotor and the stator may not be properly maintained, so it is desirable to suppress the deformation of the bridge portion.

[0007] In addition, when the resin material is a thermoplastic resin, the pressure acting on the inner surface of the magnet accommodating hole during filling with the resin material is higher than when the resin material is a thermosetting resin, and therefore the above problem becomes more pronounced. [Means for solving the problem]

[0008] A rotor for solving the above problem is a rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion that constitutes an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion that is located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connects the outer circumferential portion and the inner circumferential portion, and an inner surface of the magnet accommodating holes has a first surface that constitutes the outer circumferential portion and a second surface that constitutes the inner circumferential portion. and a second surface extending along the first surface and constituting the inner circumferential portion, and when the direction in which the first surface and the second surface face each other is defined as the facing direction, and the direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as the orthogonal direction, a blocking portion is provided inside the magnet accommodating hole that blocks the space between one of the first surface and the second surface and the outer surface of the magnet from both sides in the orthogonal direction, and the other of the first surface and the second surface, which is different from the one of the first surface and the second surface, is in contact with the outer surface of the magnet, and the resin material is filled in both portions of the magnet accommodating hole in the orthogonal direction of the magnet.

[0009] When manufacturing the rotor, if a resin material is filled between the first surface of the magnet accommodating hole and the outer surface of the magnet, the pressure of the resin material is likely to act on the outer periphery. Also, if a resin material is filled between the second surface of the magnet accommodating hole and the outer surface of the magnet, the pressure of the resin material is likely to act on the outer periphery via the magnet.

[0010] In this regard, according to the above configuration, the space between either one of the first surface or the second surface of the magnet accommodating hole and the outer surface of the magnet is blocked from both sides in the orthogonal direction by the blocking portion. In addition, the other of the first surface or the second surface is in contact with the outer surface of the magnet. Therefore, when filling the resin material into the portions of the magnet accommodating hole on both sides in the orthogonal direction of the magnet, the resin material is less likely to flow between the first surface or the second surface of the magnet accommodating hole and the outer surface of the magnet. This makes it possible to reduce the pressure of the resin material acting on the outer periphery when filling the magnet accommodating hole with the resin material. As a result, it is possible to reduce the force based on the pressure of the resin material acting toward the outer periphery of the rotor core. Therefore, it is possible to suppress deformation of the bridge portion.

[0011] A rotor for solving the above problem includes a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion that constitutes an outer circumferential surface of the rotor core, an inner circumferential portion that is located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion that is located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connects the outer circumferential portion and the inner circumferential portion, and an inner surface of the magnet accommodating holes constitutes the outer circumferential portion. When the direction in which the first surface and the second surface face each other is defined as the facing direction, and the direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as the orthogonal direction, inside the magnet accommodating hole, blocking portions are provided corresponding to each of the spaces, blocking the space between the first surface and the outer surface of the magnet, and the space between the second surface and the outer surface of the magnet from both sides in the orthogonal direction, and the resin material is filled in portions of the magnet accommodating hole on both sides of the magnet in the orthogonal direction.

[0012] When manufacturing the rotor, if a resin material is filled between the first surface of the magnet accommodating hole and the outer surface of the magnet, the pressure of the resin material is likely to act on the outer periphery. Also, if a resin material is filled between the second surface of the magnet accommodating hole and the outer surface of the magnet, the pressure of the resin material is likely to act on the outer periphery via the magnet.

[0013] In this regard, according to the above configuration, the space between the first surface of the magnet accommodating hole and the outer surface of the magnet, and the space between the second surface and the outer surface of the magnet are each blocked by blocking portions from both sides in the orthogonal direction. Therefore, when filling the resin material into the portions of the magnet accommodating hole on both sides in the orthogonal direction of the magnet, the resin material is less likely to flow between the first and second surfaces of the magnet accommodating hole and the outer surface of the magnet. This makes it possible to reduce the pressure of the resin material acting on the outer periphery when filling the magnet accommodating hole with the resin material. As a result, it is possible to reduce the force based on the pressure of the resin material acting toward the outer periphery of the rotor core. Therefore, deformation of the bridge portion can be suppressed.

[0014] A manufacturing method of a rotor for solving the above problem includes a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion that constitutes an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion that is located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connects the outer circumferential portion and the inner circumferential portion, and an inner surface of the magnet accommodating hole includes a first surface that constitutes the outer circumferential portion, and a second surface that extends along the first surface and constitutes the inner circumferential portion, When the direction in which the first surface and the second surface face each other is defined as the facing direction, and the direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as the orthogonal direction, the method includes a magnet accommodating process for accommodating the magnet in the magnet accommodating hole, and a filling process for filling the magnet accommodating hole in which the magnet is accommodated with the resin material, in which in the magnet accommodating process, the space between either one of the first surface or the second surface and the outer surface of the magnet is blocked from both sides in the orthogonal direction by a blocking portion provided inside the magnet accommodating hole, and the outer surface of the magnet is brought into contact with the other side different from the one of the first surface and the second surface, and in the filling process, the resin material is filled into both portions of the magnet accommodating hole in the orthogonal direction of the magnet.

[0015] According to the above method, it is possible to achieve effects similar to those of the first rotor. A manufacturing method of a rotor for solving the above problems includes a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion that constitutes an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion that is located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connects the outer circumferential portion and the inner circumferential portion, and the inner surface of the magnet accommodating holes has a first surface that constitutes the outer circumferential portion, and a second surface that extends along the first surface and constitutes the inner circumferential portion. The magnet accommodating hole includes two surfaces, and when the direction in which the first surface and the second surface face each other is defined as the facing direction and the direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as the orthogonal direction, the magnet accommodating hole includes a magnet accommodating process for accommodating the magnet, and a filling process for filling the magnet accommodating hole in which the magnet is accommodated with the resin material, in which in the magnet accommodating process, the space between the first surface and the outer surface of the magnet, and the space between the second surface and the outer surface of the magnet are blocked from both sides in the orthogonal direction by blocking portions provided inside the magnet accommodating hole corresponding to each of the spaces, and in the filling process, the resin material is filled into both portions of the magnet accommodating hole in the orthogonal direction of the magnet.

[0016] According to the above method, it is possible to achieve effects similar to those of the second rotor. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a plan view showing a rotor according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing the rotor of FIG. [Diagram 3] FIG. 3 is an enlarged plan view showing a magnet accommodating hole in the rotor of FIG. [Figure 4] FIG. 4 is a cross-sectional view showing a molding apparatus according to one embodiment. [Diagram 5]FIG. 5 is an enlarged cross-sectional view showing a pressing mechanism in the molding apparatus of FIG. [Figure 6] FIG. 6 is a plan view showing a state in which magnets are accommodated in the magnet accommodating holes of the rotor core shown in FIG. [Figure 7] FIG. 7 is a plan view showing a rotor of the first modified example. [Figure 8] FIG. 8 is a plan view showing a rotor of the second modified example. [Figure 9] FIG. 9 is a plan view showing a rotor of the third modified example. [Figure 10] FIG. 10 is a plan view showing a rotor of the fourth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, an embodiment of a rotor and a method for manufacturing the rotor will be described with reference to FIGS. (Rotor 10) 1, the rotor 10 includes a rotor core 11, a plurality of magnets 30, and a plurality of resin materials 40. The rotor 10 is a rotor used in, for example, an embedded magnet motor.

[0019] Rotor core 11 has a substantially cylindrical shape and is formed, for example, by laminating a plurality of core pieces punched out from electromagnetic steel sheets. Hereinafter, the axial direction of rotor core 11 will be simply referred to as the axial direction, the radial direction of rotor core 11 will be simply referred to as the radial direction, and the circumferential direction of rotor core 11 will be simply referred to as the circumferential direction.

[0020] As shown in FIG. 2, rotor core 11 has a first end face 11a and a second end face 11b located opposite to each other in the axial direction. The rotor core 11 has a central hole 12 into which a shaft (not shown) is inserted, and a plurality of magnet accommodating holes 20 in which magnets 30 are accommodated. The plurality of magnet accommodating holes 20 are formed at intervals from one another in the circumferential direction.

[0021] The center hole 12 and the magnet accommodating holes 20 penetrate the rotor core 11 in the axial direction. That is, the center hole 12 and the magnet accommodating holes 20 each open to the first end face 11a and the second end face 11b.

[0022] 3, the cross-sectional shape of the magnet accommodating hole 20 perpendicular to the axial direction is a substantially rectangular shape having long and short sides. The cross-sectional shape of the magnet accommodating hole 20 is uniform throughout the axial direction.

[0023] Rotor core 11 has an outer peripheral portion 13, an inner peripheral portion 14, and a bridge portion 15. Outer peripheral portion 13 forms the outer peripheral surface of rotor core 11. Inner peripheral portion 14 is located on the opposite side of magnet accommodating holes 20 from outer peripheral portion 13, and forms the inner peripheral surface of rotor core 11. Bridge portion 15 connects outer peripheral portion 13 and inner peripheral portion 14.

[0024] Two magnet accommodating holes 20 that are adjacent in the circumferential direction and form a pair extend in a V-shape so that the closer they are to each other, the more radially inward they are located. The bridge portion 15 is located between the radially inner ends of the two magnet accommodating holes 20.

[0025] The inner surface of the magnet accommodating hole 20 includes a first surface 21 and a second surface 22. The first surface 21 constitutes the outer circumferential portion 13. The second surface 22 extends along the first surface 21 and constitutes the inner circumferential portion 14. Therefore, the first surface 21 is located radially outward of the second surface 22.

[0026] Hereinafter, the direction in which the first surface 21 and the second surface 22 face each other will be referred to as the facing direction. Also, the direction perpendicular to both the axial direction and the facing direction will be referred to as the orthogonal direction. The facing direction coincides with the short side direction of the magnet accommodating hole 20. The orthogonal direction coincides with the long side direction of the magnet accommodating hole 20.

[0027] The magnets 30 are housed one by one in each magnet accommodating hole 20. The magnets 30 are fixed to the rotor core 11 via a resin material 40 filled in the magnet accommodating hole 20. The magnet 30 is, for example, a permanent magnet.

[0028] The magnet 30 has an elongated shape that is long in the axial direction. The length of the magnet 30 in the axial direction is shorter than the length of the rotor core 11 in the axial direction. 2, one axial end face of the magnet 30 is flush with, for example, the first end face 11a. The other axial end face of the magnet 30 opposite to the one axial end face is located, for example, more inward in the axial direction than the second end face 11b.

[0029] 3, the cross-sectional shape of magnet 30 perpendicular to the axial direction is a substantially rectangular shape having long and short sides. Magnet 30 is accommodated inside magnet accommodating hole 20 in a position in which the long side direction and the short side direction correspond to the orthogonal direction and the opposing direction, respectively.

[0030] The width of magnet 30 in the short side direction is smaller than the width of magnet 30 in the opposing direction of magnet accommodating hole 20. The width of magnet 30 in the long side direction is smaller than the width of magnet accommodating hole 20 in the orthogonal direction.

[0031] The entire first outer surface 31 on one side of the short side direction of the magnet 30 is in contact with the first surface 21. The second outer surface 32 on the opposite side of the magnet 30 to the first outer surface 31 is separated from the second surface 22. In other words, a gap exists between the second outer surface 32 and the second surface 22.

[0032] A blocking portion 23 is provided inside the magnet accommodating hole 20 to block the space between the second surface 22 and the second outer surface 32 from both sides in the perpendicular direction. The blocking portion 23 is configured by a pair of protrusions 24 that protrude in opposing directions from the second surface 22 and are formed at an interval from each other in the perpendicular direction.

[0033] The protrusion 24 extends in the axial direction over the entire axial direction of the second surface 22. That is, the protrusion 24 extends from the first end face 11a to the second end face 11b. The protrusion 24 is formed integrally with the second surface 22. That is, the protrusion 24 is formed continuously with the second surface 22 without any break.

[0034] The distance between the pair of protrusions 24 in the orthogonal direction is shorter than the long side of the magnet 30. Therefore, the protrusions 24 are located between the second surface 22 and the second outer surface 32 in the facing direction. The protrusions 24 are in contact with the second outer surface 32 of the magnet 30 in the facing direction.

[0035] The portion of the protrusion 24 that contacts the second outer surface 32 is curved so as to be convex toward the second outer surface 32. The cross-sectional shape of the protrusion 24 perpendicular to the axial direction is, for example, semicircular.

[0036] Before the magnet 30 is accommodated in the magnet accommodating hole 20, the distance between the first surface 21 and the protrusion 24 in the opposing direction is slightly shorter than the short side of the magnet 30. Therefore, the magnet 30 is press-fitted between the first surface 21 and the protrusion 24.

[0037] Positioning portions 25 are formed on the second surface 22 on the outer side of the pair of protrusions 24 in the orthogonal direction. The outer side in the orthogonal direction refers to the side away from the middle portion on the second surface 22 that is equidistant from the pair of protrusions 24 in the orthogonal direction. The positioning portions 25 position the magnet 30 in the orthogonal direction, which may move due to the pressure of the resin material 40 when the resin material 40 is filled into the magnet accommodating hole 20. The positioning portions 25 are formed of convex portions protruding from the second surface 22. At least one of the two positioning portions 25 is in contact with the outer surface constituting the short side of the magnet 30 from the outer side in the orthogonal direction.

[0038] Two recesses 26 are formed on the second surface 22 to allow relief for both corners in the long side direction of the magnet 30. The recesses 26 are recessed from the second surface 22 toward the inner periphery 14. The recesses 26 are connected to the positioning portion 25 on the inside in the orthogonal direction of the positioning portion 25. The inside in the orthogonal direction is the side opposite to the outside in the orthogonal direction described above, and refers to the side approaching the middle part on the second surface 22 that is equidistant from the pair of protrusions 24 in the orthogonal direction.

[0039] The resin material 40 is filled in both portions of the magnet accommodating hole 20 in the direction perpendicular to the magnet 30. One end face in the axial direction of the resin material 40 is flush with one end face in the axial direction of the magnet 30 and the first end face 11a of the rotor core 11.

[0040] The resin material 40 is, for example, a thermoplastic resin such as a liquid crystal polymer. In the space defined by the second surface 22 of the magnet accommodating hole 20, the second outer surface 32 of the magnet 30, and the pair of protrusions 24, an unfilled portion 20a is formed, which is not filled with the resin material 40. The unfilled portion 20a is formed over the entirety in the axial direction of the rotor 10. When the magnet accommodating hole 20 is filled with the resin material 40, a pressing member 71 (described later) comes into contact with the other end face of the magnet 30 opposite to the one end face. Therefore, the other end face of the magnet 30 in the axial direction is not covered with the resin material 40. The inside of the recess 26 is filled with the resin material 40.

[0041] (Molding device 50) Next, a molding device 50 for filling the magnet accommodating hole 20 with the resin material 40 will be described. As shown in FIG. 4, the molding apparatus 50 includes a first mold 60 and a second mold 80 .

[0042] (1st type 60) The first mold 60 includes a first mold body 61 and a pallet 62 . The first mold body 61 has a support surface that supports the lower surface of the pallet 62 .

[0043] The pallet 62 is transported between the first die body 61 and the second die 80 while supporting the rotor core 11 . The pallet 62 includes a base plate 63, a post 64 protruding from the center of the base plate 63, and a spacer 66 disposed on the upper surface of the base plate 63. The post 64 penetrates the spacer 66.

[0044] The base plate 63 and the spacer 66 are each formed into a flat plate shape. The post 64 is formed into a cylindrical shape. A plurality of through holes 63a are provided at intervals in the circumferential direction in a portion of the base plate 63 on the outer circumferential side of the post 64. The through holes 63a are covered with a spacer 66.

[0045] The post 64 is inserted into the central hole 12 of the rotor core 11. A plurality of engagement pins 65 are provided at the tip of the post 64 at intervals in the circumferential direction. The spacer 66 supports the second end surface 11b of the rotor core 11 into which the post 64 is inserted.

[0046] 5, a stepped hole 67 penetrating the spacer 66 in the thickness direction is formed in a portion of the spacer 66 facing each magnet accommodating hole 20. The stepped hole 67 has a large diameter portion facing the base plate 63 and a small diameter portion facing the magnet accommodating hole 20.

[0047] A pressing mechanism 70 is provided inside the stepped hole 67. The pressing mechanism 70 has a pressing member 71 that presses the magnet 30 toward the second die 80, and a biasing member 74 that biases the pressing member 71 toward the second die 80.

[0048] The pressing member 71 is accommodated inside the stepped hole 67 so as to be able to reciprocate in the thickness direction of the spacer 66. The pressing member 71 has a support portion 72 that supports the other end face of the magnet 30, and a flange portion 73 that prevents the support portion 72 from slipping out of the stepped hole 67.

[0049] The support portion 72 is housed in the small diameter portion of the stepped hole 67. The support portion 72 has a substantially rectangular shape in a plan view. The width of the support portion 72 in the orthogonal direction is, for example, longer than the distance between the protrusions 24 in the orthogonal direction and shorter than the distance between the positioning portions 25 in the orthogonal direction. The width of the support portion 72 in the opposing direction is, for example, the same as the distance between the first surface 21 and the positioning portion 25 in the opposing direction.

[0050] The flange portion 73 is housed in the large diameter portion of the stepped hole 67. The flange portion 73 protrudes outward from the lower end portion of the support portion 72. The flange portion 73 comes into contact with the inner surface of the stepped hole 67 from below, thereby restricting the upward movement of the pressing member 71.

[0051] The biasing member 74 is, for example, a coil spring. Both ends of the biasing member 74 are connected to the base plate 63 and the flange portion 73, respectively. (2nd type 80) 4, the second mold 80 includes a second mold body 81 and a gate plate 83. The second mold body 81 and the gate plate 83 are, for example, configured as separate bodies. The second mold 80 is an example of a "metal mold".

[0052] The second mold body 81 is, for example, a movable mold configured to be able to advance and retreat with respect to the first mold body 61. The second mold body 81 has a sprue 82 through which the resin material 40 injected from an injection device (not shown) flows.

[0053] The gate plate 83 is disposed between the second die body 81 and the rotor core 11. The gate plate 83 has a runner 84 that communicates with the sprue 82, and a plurality of gates 85 that extend from the runner 84.

[0054] The runners 84 open to an upper surface of the gate plate 83. The runners 84 extend radially in the radial direction from the center of the gate plate 83. The gate 85 opens to a lower surface of the gate plate 83. The gate 85 communicates between the runners 84 and the magnet accommodating hole 20.

[0055] Two gates 85 are in communication with one magnet accommodating hole 20. The two gates 85 are in communication with both sides of the magnet accommodating hole 20 in the orthogonal direction. The two gates 85 may branch off and extend from one runner 84, or may extend from two different runners 84, respectively.

[0056] A plurality of engagement holes 86 into which the plurality of engagement pins 65 of the post 64 engage are provided on the lower surface of the gate plate 83. The engagement pins 65 engage with the engagement holes 86, whereby the gate plate 83 is positioned relative to the pallet 62.

[0057] (Method of manufacturing rotor 10) The manufacturing method of the rotor 10 includes a magnet housing step, an arrangement step, a pressing step, a filling step, and a solidification step. The magnet housing step, arrangement step, pressing step, filling step, and solidification step are performed in this order.

[0058] As shown in FIG. 4, in the magnet accommodating step, the magnets 30 are accommodated in the magnet accommodating holes 20 of the rotor core 11 supported by a pallet 62. 6, the distance between the first surface 21 and the protrusions 24 in the facing direction is slightly shorter than the short side of the magnet 30, so the magnet 30 is accommodated while sliding between the first surface 21 and the two protrusions 24. That is, the magnet 30 is press-fitted into the magnet accommodating hole 20. This positions the magnet 30 in the facing direction.

[0059] Thereafter, the pallet 62 is placed between the first mold body 61 and the second mold body 81 . 5, in the arrangement step, the gate plate 83 is arranged on the first end face 11a of the rotor core 11. At this time, the gates 85 face both side portions of the magnet accommodating hole 20 in the orthogonal direction to the magnet 30.

[0060] In the pressing step, the gate plate 83 is disposed on the first end surface 11a of the rotor core 11 so as to cover the openings of each magnet accommodating hole 20, whereby the pressing mechanism 70 presses the magnets 30 against the lower surface of the gate plate 83.

[0061] Until the gate plate 83 is disposed on the first end face 11a of the rotor core 11, the flange portion 73 of the pressing member 71 contacts the inner surface of the stepped hole 67 from below, thereby restricting the upward movement of the pressing member 71. At this time, the upper end portion of the magnet 30 supported by the pressing member 71 protrudes upward from the first end face 11a of the rotor core 11. By disposing the gate plate 83 on the first end face 11a of the rotor core 11, the pressing member 71 is pressed down via the magnet 30 against the biasing force of the biasing member 74. As a result, the magnet 30 is pressed against the lower surface of the gate plate 83 via the pressing member 71 by the biasing force of the biasing member 74. At this time, the flange portion 73 is separated downward from the inner surface of the stepped hole 67.

[0062] As shown in Fig. 6, in the filling step, with the first die 60 and the second die 80 clamped together, resin material 40 is filled through two gates 85 into both sides of the magnet accommodating hole 20 in the orthogonal direction to the magnet 30. At this time, the space between the second surface 22 of the magnet accommodating hole 20 and the second outer surface 32 of the magnet 30 is blocked from both sides in the orthogonal direction by a pair of protrusions 24, so that the space is not filled with resin material 40. Therefore, as shown in Fig. 3, an unfilled portion 20a is formed in the space.

[0063] In the solidification process, the rotor core 11 is cooled to solidify the resin material 40 filled in the magnet accommodating holes 20. The rotor core 11 may be cooled by leaving the rotor core 11 in a room temperature atmosphere, or may be cooled by using a cooling device that blows air.

[0064] Next, although not shown, the spacer 66 is pressed from below by a lifting member inserted into the through hole 63a of the base plate 63. As a result, the rotor core 11 moves together with the spacer 66 in a direction to come out of the post 64, and the rotor core 11 is removed from the post 64.

[0065] The rotor 10 is manufactured in this manner. The operation of this embodiment will be described. When manufacturing the rotor 10, if the resin material 40 is filled between the first surface 21 of the magnet accommodating hole 20 and the first outer surface 31 of the magnet 30, the pressure of the resin material 40 is likely to act on the outer circumferential portion 13. Also, if the resin material 40 is filled between the second surface 22 of the magnet accommodating hole 20 and the second outer surface 32 of the magnet 30, the pressure of the resin material 40 is likely to act on the outer circumferential portion 13 via the magnet 30.

[0066] In this regard, according to the rotor 10 of this embodiment, the space between the second surface 22 of the magnet accommodating hole 20 and the second outer surface 32 of the magnet 30 is blocked from both sides in the orthogonal direction by a pair of protrusions 24. Also, the first surface 21 of the magnet accommodating hole 20 is in contact with the first outer surface 31 of the magnet 30. For this reason, when the resin material 40 is filled into the portions of the magnet accommodating hole 20 on both sides in the orthogonal direction of the magnet 30, the resin material 40 is less likely to flow between the first surface 21 and the first outer surface 31 and between the second surface 22 and the second outer surface 32.

[0067] The effects of this embodiment will be described. (1) A pair of protrusions 24 are provided inside magnet accommodating hole 20 to close the space between second surface 22 and second outer surface 32 from both sides in the perpendicular direction. First surface 21 is in contact with first outer surface 31. Resin material 40 is filled in portions of magnet accommodating hole 20 on both sides in the perpendicular direction to magnet 30.

[0068] According to the above configuration, it is possible to reduce the pressure of the resin material 40 acting on the outer periphery 13 when the resin material 40 is filled into the magnet accommodating holes 20. As a result, it is possible to reduce the force based on the pressure of the resin material 40 acting toward the outer periphery side of the rotor core 11. Therefore, deformation of the bridge portions 15 can be suppressed.

[0069] (2) The protrusion 24 is provided between the second surface 22 and the second outer surface 32 in the opposing direction. The protrusion 24 is in contact with the second outer surface 32. According to the above configuration, the magnet 30 is positioned in the opposing direction by contacting the protrusion 24 with the magnet 30. Therefore, the resin material 40 is less likely to flow between the first surface 21 and the first outer surface 31, and between the second surface 22 and the second outer surface 32.

[0070] Moreover, it is possible to prevent the position of the magnet 30 from shifting in the opposing direction due to the centrifugal force generated when the rotor 10 rotates. (3) The portion of the protrusion 24 that comes into contact with the second outer surface 32 is curved so as to be convex toward the second outer surface 32 .

[0071] According to the above configuration, the contact area between the protrusion 24 and the magnet 30 can be made smaller than when the portion of the protrusion 24 that contacts the second outer surface 32 is a flat surface along the second outer surface 32. This reduces the sliding resistance between the magnet 30 and the protrusion 24 when the magnet 30 is accommodated in the magnet accommodating hole 20. Therefore, the magnet 30 can be easily accommodated in the magnet accommodating hole 20.

[0072] (4) The blocking portion 23 is constituted by a pair of protrusions 24 that protrude in opposing directions from the second surface 22 and are formed at an interval from each other in the perpendicular direction. According to the above configuration, the number of types of parts constituting the rotor 10 can be reduced compared to when the blocking portion 23 is a separate member from the rotor core 11. This makes it possible to prevent the configuration of the rotor 10 from becoming complicated. Also, the rotor 10 can be easily manufactured.

[0073] (5) The two magnet accommodating holes 20 extend so that the farther they are from the bridge portion 15, the more radially outwardly they are positioned in the rotor core 11. When the two magnet accommodating holes 20 extend so as to be positioned radially outward of the rotor core 11 as they move away from the bridge portion 15, the first surfaces 21 of the two magnet accommodating holes 20 face each other in the circumferential direction. Therefore, the pressure of the resin material 40 acting on each of the first surfaces 21 of the two magnet accommodating holes 20 acts on the portion of the outer circumferential portion 13 positioned between the two magnet accommodating holes 20. As a result, deformation of the bridge portion 15 is likely to occur.

[0074] In this regard, according to the above configuration, when the resin material 40 is filled into the magnet accommodating hole 20, the resin material 40 is less likely to flow between the first surface 21 and the first outer surface 31 and between the second surface 22 and the second outer surface 32. This makes it possible to reduce the pressure of the resin material 40 acting on each of the first surfaces 21 of the two magnet accommodating holes 20. Therefore, deformation of the bridge portion 15 can be effectively suppressed.

[0075] (6) In the magnet accommodating process, the space between the second surface 22 and the second outer surface 32 is blocked from both sides in the orthogonal direction by a pair of protrusions 24 provided inside the magnet accommodating hole 20, and the first outer surface 31 is brought into contact with the first surface 21. In the filling process, the resin material 40 is filled into both portions of the magnet accommodating hole 20 in the orthogonal direction to the magnet 30.

[0076] According to the above method, an effect similar to the above effect (1) can be achieved. (7) In the arrangement process, before the filling process, a gate plate 83 having a gate 85 is arranged on the first end surface 11a of the rotor core 11 so as to cover the opening of the magnet accommodating hole 20 in which the magnet 30 is accommodated. In the pressing process, the magnet 30 accommodated in the magnet accommodating hole 20 is pressed against the lower surface of the gate plate 83.

[0077] The space defined by the second surface 22, the second outer surface 32, and the pair of protrusions 24 is located inside the magnet accommodating hole 20. For this reason, when the length of the magnet 30 in the axial direction is shorter than the length of the rotor core 11 in the axial direction, the above-mentioned space communicates with the other portion inside the magnet accommodating hole 20. In this case, there is a risk that the resin material 40 will flow into the above-mentioned space during the filling process.

[0078] In this regard, according to the above method, the magnet 30 is pressed against the gate plate 83 before the resin material 40 is injected into the magnet accommodating hole 20. As a result, on the side of the inside of the magnet accommodating hole 20 where the gate plate 83 is located, the above-mentioned space is separated from the portion other than the above-mentioned space by the magnet 30. Therefore, even if the length of the magnet 30 in the axial direction is shorter than the length of the rotor core 11 in the axial direction, it is possible to prevent the resin material 40 from flowing into the above-mentioned space during the filling step.

[0079] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0080] The pressing mechanism 70 may have an actuator that raises and lowers the pressing member 71, instead of the biasing member 74. In this case, the pressing of the magnet 30 by the pressing member 71 may be delayed with respect to the arrangement of the gate plate 83 onto the rotor core 11.

[0081] The pressing step may be omitted. In this case, the length of the magnet 30 in the axial direction may be the same as the length of the rotor core 11 in the axial direction, or may be shorter than the length of the rotor core 11. When the length of the magnet 30 is shorter than the length of the rotor core 11, at the upper end of the magnet accommodating hole 20, the space partitioned by the second surface 22, the second outer surface 32, and the protrusion 24 communicates with the portion other than the space. For this reason, it is preferable to adjust the amount of the resin material 40 filled in the magnet accommodating hole 20 so that the resin material 40 does not exceed the upper surface of the magnet 30.

[0082] The two magnet accommodating holes 20 may extend in a V-shape so that the closer they are to each other, the more radially outward they are positioned. Even in this case, deformation of the bridge portion located between the radially outer ends of the two magnet accommodating holes 20 can be suppressed.

[0083] The pair of magnet accommodating holes 20 is not limited to extending in a V-shape. For example, the two magnet accommodating holes 20 may be arranged side by side in a direction perpendicular to both the axial direction and the radial direction so that their longitudinal directions coincide with each other. Even in this case, deformation of the bridge portion located between the opposing ends of the two magnet accommodating holes 20 can be suppressed.

[0084] Three or more protrusions 24 may be provided in the perpendicular directions. 7, the blocking portion 23 may be formed of a separate member from the rotor core 11. In this case, the blocking portion 23 may be formed of two ridges, or may have two ridges and a connecting portion that connects the ridges to each other. The blocking portion 23 may be bonded to the inner surface of the magnet accommodating hole 20. In the magnet accommodating step, the magnet 30 may be accommodated in the magnet accommodating hole 20 in which the blocking portion 23 is arranged, or the blocking portion 23 may be accommodated in the magnet accommodating hole 20 in which the magnet 30 is arranged.

[0085] The tip of the protrusion 24 in the protruding direction may have a flat surface along the outer surface of the magnet 30. In this case, the contact area between the protrusion 24 and the magnet 30 can be increased, so that the inflow of the resin material 40 into the space between the protrusion 24 and the outer surface of the magnet 30 can be effectively suppressed.

[0086] 8, the inner surfaces of the pair of protrusions 24 in the orthogonal direction may contact the outer surface of the magnet 30 from the outside in the orthogonal direction. In this case, it is preferable that the magnet 30 is press-fitted between the pair of protrusions 24 to restrict misalignment of the magnet 30 in the facing direction. In this case, since the magnet 30 is positioned in the orthogonal direction by the protrusions 24, the positioning portion 25 may be omitted.

[0087] Instead of the pair of protrusions 24 protruding from the second surface 22, a pair of protrusions 24 protruding from the first surface 21 may be used. In this case, the space between the first surface 21 and the first outer surface 31 is blocked from both sides in the perpendicular direction by the pair of protrusions 24 protruding from the first surface 21. In addition, the second surface 22 contacts the second outer surface 32. Even with this configuration, an effect similar to the above-mentioned effect (1) can be achieved.

[0088] As shown in FIG. 9, inside the magnet accommodating hole 20, blocking portions 23 that block the space between the first surface 21 and the first outer surface 31 and the space between the second surface 22 and the second outer surface 32 from both sides in the perpendicular direction may be provided corresponding to the above spaces. In this case, unfilled portions 20a are formed in both sides of the magnet accommodating hole 20 in the opposing direction of the magnet 30. Even with this configuration, when filling the resin material 40 into both sides of the magnet accommodating hole 20 in the perpendicular direction of the magnet 30, the resin material 40 is less likely to flow between the first surface 21 and the first outer surface 31 and between the second surface 22 and the second outer surface 32. In the magnet accommodating step in the manufacture of the rotor 10, the space between the first surface 21 and the first outer surface 31 and the space between the second surface 22 and the second outer surface 32 are blocked from both sides in the perpendicular direction by the blocking portions 23 provided corresponding to the above spaces. In the filling step, the resin material 40 is filled into the magnet accommodating holes 20 on both sides in the orthogonal direction of the magnets 30. The rotor 10 and the manufacturing method for the rotor 10 according to this modified example can achieve an effect similar to the effect (1) described above.

[0089] 10, two magnets 130 may be housed in one magnet accommodating hole 20. In this case, one protrusion 24 may be in contact with one magnet 130. When four or more protrusions 24 are provided, two or more protrusions 24 may be in contact with one magnet 130.

[0090] The resin material 40 may be a thermosetting resin such as an epoxy resin. The above embodiment includes the configurations described in the following supplementary notes. [Appendix 1] A rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, and an inner surface of the magnet accommodating hole has a first surface constituting the outer circumferential portion and a bridge portion extending along the first surface. a second surface constituting the inner periphery and a second surface facing each other, wherein when a direction in which the first surface and the second surface face each other is defined as an opposing direction and a direction perpendicular to both the axial direction of the rotor core and the opposing direction is defined as an orthogonal direction, a blocking portion is provided inside the magnet accommodating hole for blocking a space between one of the first surface or the second surface and an outer surface of the magnet from both sides in the orthogonal direction, the other of the first surface and the second surface, which is different from the one of the first surface and the second surface, is in contact with the outer surface of the magnet, and the resin material is filled in portions of the magnet accommodating hole on both sides in the orthogonal direction of the magnet.

[0091] [Appendix 2] A rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, wherein the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, and an inner surface of the magnet accommodating holes has a first surface constituting the outer circumferential portion and a second surface constituting the inner circumferential portion. a second surface extending along the first surface and constituting the inner circumferential portion, wherein when the direction in which the first surface and the second surface face each other is defined as the facing direction and the direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as the orthogonal direction, inside the magnet accommodating hole, blocking portions are provided corresponding to each of the spaces, blocking the space between the first surface and the outer surface of the magnet and the space between the second surface and the outer surface of the magnet from both sides in the orthogonal direction, and the resin material is filled in the portions of the magnet accommodating hole on both sides of the magnet in the orthogonal direction.

[0092] [Appendix 3] A rotor described in [Appendix 1] or [Appendix 2], wherein the blocking portion is provided between the inner surface of the magnet accommodating hole and the outer surface of the magnet in the opposing direction and is in contact with the outer surface of the magnet.

[0093] [Appendix 4] A rotor as described in [Appendix 3], wherein the portion of the blocking portion that contacts the outer surface of the magnet is curved so as to be convex toward the outer surface of the magnet. [Appendix 5] A rotor described in any one of [Appendix 1] to [Appendix 4], wherein the blocking portion is composed of a pair of protrusions that protrude in the opposing direction from the inner surface of the magnet accommodating hole and are formed at a distance from each other in the perpendicular direction.

[0094] [Appendix 6] A rotor described in any one of [Appendix 1] to [Appendix 5], wherein the two magnet accommodating holes extend so as to be positioned radially outward of the rotor core as they move away from the bridge portion. [Explanation of symbols]

[0095] 10...Rotor 11...Rotor core 11a...first end surface 11b…Second end surface 12...Center hole 13...Outer periphery 14...Inner circumference 15…Bridge section 20...Magnet receiving hole 20a…Unfilled section 21...Side 1 22…Second side 23…Occluded part 24…Protrusion 25… Positioning part 26…Recess 30,130…Magnet 31...First outer surface 32…Second outer surface 40…Resin material 50…Molding device 60…Type 1 61…Type 1 main body 62…Palette 63…Base plate 63a...Through hole 64…Post 65...Engagement pin 66…Spacer 67...Step hole 70…Pushing mechanism 71... Pressing member 72...Support part 73…Flange 74... Urging member 80…Second type (mold) 81…Type 2 main body 82…Sprue 83…Gate plate 84…Runner 85…Gate 86…Engagement hole

Claims

1. A rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, an inner surface of the magnet accommodating hole includes a first surface constituting the outer circumferential portion and a second surface extending along the first surface and constituting the inner circumferential portion, When a direction in which the first surface and the second surface face each other is defined as a facing direction, and a direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as an orthogonal direction, a blocking portion is provided inside the magnet accommodating hole to block a space between one of the first surface and the second surface and an outer surface of the magnet from both sides in the perpendicular direction, the other of the first surface and the second surface is in contact with an outer surface of the magnet; The resin material is filled in both portions of the magnet accommodating hole in the orthogonal direction of the magnet. Rotor.

2. A rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, an inner surface of the magnet accommodating hole includes a first surface constituting the outer circumferential portion and a second surface extending along the first surface and constituting the inner circumferential portion, When a direction in which the first surface and the second surface face each other is defined as a facing direction, and a direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as an orthogonal direction, a blocking portion is provided inside the magnet accommodating hole to block a space between the first surface and an outer surface of the magnet and a space between the second surface and the outer surface of the magnet from both sides in the perpendicular direction, the blocking portion corresponding to each of the spaces; The resin material is filled in both portions of the magnet accommodating hole in the orthogonal direction of the magnet. Rotor.

3. The blocking portion is provided between an inner surface of the magnet accommodating hole and an outer surface of the magnet in the opposing direction and is in contact with the outer surface of the magnet. A rotor according to claim 1 or 2.

4. A portion of the blocking portion that contacts the outer surface of the magnet is curved so as to be convex toward the outer surface of the magnet. A rotor according to claim 3.

5. The blocking portion is configured by a pair of protrusions that protrude from an inner surface of the magnet accommodating hole in the opposing direction and are formed at an interval from each other in the perpendicular direction. A rotor according to claim 1 or 2.

6. The two magnet accommodating holes extend so as to be positioned radially outward of the rotor core as they move away from the bridge portion. A rotor according to claim 1 or 2.

7. A manufacturing method of a rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, comprising: the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, an inner surface of the magnet accommodating hole includes a first surface constituting the outer circumferential portion and a second surface extending along the first surface and constituting the inner circumferential portion, When a direction in which the first surface and the second surface face each other is defined as a facing direction, and a direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as an orthogonal direction, a magnet accommodating step of accommodating the magnet in the magnet accommodating hole; and a filling step of filling the magnet accommodating hole in which the magnet is accommodated with the resin material, In the magnet accommodating step, a space between one of the first surface and the second surface and an outer surface of the magnet is closed from both sides in the orthogonal direction by a closing portion provided inside the magnet accommodating hole, and the outer surface of the magnet is brought into contact with the other surface different from the one of the first surface and the second surface, In the filling step, the resin material is filled into both sides of the magnet accommodating hole in the orthogonal direction of the magnet. A method for manufacturing a rotor.

8. A manufacturing method of a rotor including a cylindrical rotor core having a plurality of magnet accommodating holes, magnets accommodated in the magnet accommodating holes, and a resin material filled in the magnet accommodating holes and fixing the magnets to the rotor core, comprising: the rotor core has an outer circumferential portion constituting an outer circumferential surface of the rotor core, an inner circumferential portion located on the opposite side of the magnet accommodating holes from the outer circumferential portion, and a bridge portion located between two adjacent magnet accommodating holes in the circumferential direction of the rotor core and connecting the outer circumferential portion and the inner circumferential portion, an inner surface of the magnet accommodating hole includes a first surface constituting the outer circumferential portion and a second surface extending along the first surface and constituting the inner circumferential portion, When a direction in which the first surface and the second surface face each other is defined as a facing direction, and a direction perpendicular to both the axial direction of the rotor core and the facing direction is defined as an orthogonal direction, a magnet accommodating step of accommodating the magnet in the magnet accommodating hole; and a filling step of filling the magnet accommodating hole in which the magnet is accommodated with the resin material, In the magnet accommodating step, a space between the first surface and an outer surface of the magnet, and a space between the second surface and an outer surface of the magnet are closed from both sides in the orthogonal direction by closing portions provided inside the magnet accommodating hole corresponding to each of the spaces, In the filling step, the resin material is filled into both sides of the magnet accommodating hole in the orthogonal direction of the magnet. A method for manufacturing a rotor.

9. an arrangement step, prior to the filling step, of arranging a die having a gate for injecting the resin material into the magnet accommodating hole on an axial end face of the rotor core so as to cover an opening of the magnet accommodating hole in which the magnet is accommodated; and a pressing step of pressing the magnet accommodated in the magnet accommodation hole against the die. A method for manufacturing a rotor according to claim 7 or 8.

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