Rotor, laminate, method for manufacturing core, and method for manufacturing rotor

Abstract

Provided is a rotor that enables an improvement in magnet holding force. The present invention comprises: a core 2 formed by laminating a plurality of core pieces 3; magnet insertion holes 5 provided in the lamination direction of the core pieces 3 of the core 2; magnets 7 inserted into the magnet insertion holes 5; and spring pieces 25 provided to opposing inner surfaces 11 of the magnet insertion holes 5 and pressing the magnets 7 against inner surfaces 13 of the magnet insertion holes 5. Each spring piece 25 is doubly supported with a base end 24a thereof integral with the inner surface 11 of the magnet insertion hole 5 and a tip end 24a thereof in contact with the inner surface 11 of the magnet insertion hole 5. An intermediate portion 24c between the base end 24a and the tip end 24b protrudes toward and elastically contacts the magnet 7.

Description

Manufacturing method of rotor, laminate, core, and rotor

[0008]

[0001] The present invention relates to a rotor used in a rotating electrical machine, a laminate, a manufacturing method of a core, and a manufacturing method of a rotor.

[0002] As a conventional rotor, for example, there is one described in Patent Document 1.

[0003] This rotor is manufactured by inserting and holding a magnet in a magnet insertion hole of a core. In holding the magnet, a protrusion is projected into the magnet insertion hole, and the magnet is brought into contact with the inner surface of the magnet insertion hole by the elasticity of this protrusion.

[0004] However, since the protrusion is provided in a cantilever state and elastically contacts the magnet, there is a limit to the holding force of the magnet.

[0005] Japanese Unexamined Patent Application Publication No. 2024 - 99235

[0006] The problem to be solved is that there is a limit to the holding force of the magnet.

[0007] The present invention provides a rotor including a core formed by laminating a plurality of core pieces, a magnet insertion hole provided in the core pieces of the core in the lamination direction, a magnet inserted into the magnet insertion hole, and a spring piece provided between the inner surface of the magnet insertion hole facing each other and the outer surface of the magnet to hold the magnet in the magnet insertion hole. The spring piece has a both - end - supported state having a base end held on one of the inner surface of the magnet insertion hole and the outer surface of the magnet and a tip contacting one of the inner surface of the magnet insertion hole and the outer surface of the magnet, and an intermediate portion between the base end and the tip bulges and elastically contacts the other of the inner surface of the magnet insertion hole and the outer surface of the magnet.

[0008] Furthermore, the present invention provides a laminate comprising a main body formed by stacking a plurality of core pieces, a magnet insertion hole provided in the stacking direction of the core pieces of the main body, and a convex piece provided on one of the opposing inner surfaces of the magnet insertion hole and extending toward the other inner surface. The magnet insertion hole has a support area for the insert on one side of the inner surface and an insertion area for the insert on the other side of the inner surface relative to the support area. The convex piece is cantilevered, having an integral base end on one of the inner surfaces of the magnet insertion hole, and protrudes from the support area to the insertion area, and has a curved portion directed toward one side in the stacking direction within the insertion area and an extended portion between the curved portion and the base end.

[0009] Furthermore, the present invention provides a method for manufacturing a core using such a laminate. This method for manufacturing a core involves inserting an insert into the insertion area of ​​the magnet insertion hole and pressing the protrusion in the insertion area toward one side in the lamination direction. This pressing deforms the protrusion at least within the support area, causing the deformed portion to pivot toward one side in the lamination direction. This rotation causes the tip of the protrusion to contact one side of the inner surface of the magnet insertion hole, making the protrusion a double-supported spring piece.

[0010] Furthermore, the present invention provides a method for manufacturing a rotor using such a core manufacturing method. The insert is a magnet, and by inserting the magnet into the magnet insertion hole, the convex piece becomes the double-supported spring piece, and the intermediate portion of the spring piece between the tip and the base end elastically contacts the magnet.

[0011] This invention improves the holding force of a magnet by using a double-supported spring piece.

[0012] Figure 1 is a plan view of a rotor according to Embodiment 1 of the present invention. Figure 2 is an enlarged plan view showing the area around the magnet insertion hole of the rotor in Figure 1. Figure 3 is a cross-sectional view taken along line III-III of Figure 2. Figure 4 is an enlarged view showing a part of Figure 3. Figure 5 is an enlarged plan view showing the area around the magnet insertion hole of the core piece without a spring piece of the rotor in Figure 1. Figure 6 is an enlarged plan view showing the area around the magnet insertion hole of Figure 2 before magnet insertion. Figure 7 is a cross-sectional view taken along line VII-VII of Figure 6. Figure 8 is an enlarged view showing a part of Figure 7. Figure 9 is an enlarged cross-sectional view showing the initial stage of magnet insertion into the magnet insertion hole of Figure 7. Figure 10 is an enlarged cross-sectional view showing a part of a rotor according to Embodiment 2 of the present invention. Figure 11 is an enlarged cross-sectional view showing a part of a rotor according to Embodiment 3 of the present invention. Figure 12 is an enlarged view showing a part of Figure 11. Figure 13 is an enlarged cross-sectional view showing a part of a rotor according to Embodiment 4 of the present invention. Figure 14 is an enlarged view showing a part of Figure 13. Figure 15 is an enlarged cross-sectional view showing a part of a rotor according to Embodiment 5 of the present invention. Figure 16 is an enlarged cross-sectional view showing the insertion of a magnet into the magnet insertion hole in Example 5. Figure 17 is an enlarged cross-sectional view relating to a modified example of Example 5, showing the insertion of a magnet into the magnet insertion hole.

[0013] In one embodiment, the rotor 1 comprises a core 2, a magnet insertion hole 5, a magnet 7, and a spring piece 25. The core 2 is formed by stacking a plurality of core pieces 3. The magnet insertion hole 5 is provided in the direction of stacking the core pieces 3 of the core 2. The magnet 7 is inserted into the magnet insertion hole 5. The spring piece 25 is provided between the inner surfaces 11 of the magnet insertion hole 5 and the outer surfaces 14 of the magnet 7, which are opposite to each other, and holds the magnet 7 inside the magnet insertion hole 5.

[0014] The spring piece 25 is double-supported, having a base end 24a held by one of the inner surface 11 of the magnet insertion hole 5 and the outer surface 14 of the magnet 7, and a tip end 24b that abuts against the other of the inner surface 11 of the magnet insertion hole 5 and the outer surface 14 of the magnet 7. The intermediate portion 24c between the base end 24a and the tip end 24b of the spring piece 25 bulges out and elastically contacts the other of the inner surface 11 of the magnet insertion hole 5 and the outer surface 14 of the magnet 7.

[0015] In one embodiment, the spring piece 25 has its base end 24a held against the inner surface 11 of the magnet insertion hole 5, its tip 24b in contact with the inner surface 11 of the magnet insertion hole 5, and its middle portion 24c elastically in contact with the outer surface 14 of the magnet 7.

[0016] In another embodiment, the spring piece 25 has its base end 24a held by the outer surface 14 of the magnet 7, its tip 24b in contact with the outer surface 14 of the magnet 7, and its middle portion 24c elastically in contact with the inner surface 11 of the magnet insertion hole 5.

[0017] The spring piece 25 can take on any shape, but it may also have a curved portion 25a that extends from the contact portion 25d that elastically contacts the outer surface 14 of the magnet 7 or the inner surface 11 of the magnet insertion hole 5 to the tip 24b. The number of spring pieces 25 is arbitrary, and multiple spring pieces 25 may be provided in the axial direction of the magnet insertion hole 5.

[0018] When the spring piece 25 is held on the inner surface 11 of the magnet insertion hole 5, the magnet insertion hole 5 may have a receiving portion 27 that receives the tip 24b of the spring piece 25 in the stacking direction.

[0019] The laminated body 2A for forming the core or block comprises a main body portion 2Aa, a magnet insertion hole 5, and a protruding piece 25A. The main body portion 2Aa is made up of multiple core pieces 3 stacked together. The magnet insertion hole 5 is provided in the direction of stacking the core pieces 3 of the main body portion 2Aa. The protruding piece 25A is provided on one of the opposing inner surfaces 11 and 13 of the magnet insertion hole 5 and extends toward the other inner surface 11 and 13.

[0020] The magnet insertion hole 5 has a support area 19 for the insert 7 on one side of the inner surfaces 11 and 13, and an insertion area 17 for the insert 7 on the other side of the inner surfaces 11 and 13 relative to the support area 19. The protruding piece 25A is cantilevered, having an integral base end 24a on one of the inner surfaces 11 and 13 of the magnet insertion hole 5, and protrudes from the support area 19 to the insertion area 17. Within the insertion area 17, the protruding piece 25A has a curved portion 25a directed toward one side in the stacking direction and an extended portion 25c between this curved portion 25a and the base end 24a.

[0021] The magnet insertion hole 5 includes a recess 21 in the opposite direction on the inner surface 13, and the support area 19 may be provided within the recess 21.

[0022] The manufacturing method for the core 2 using this laminate 2A involves inserting the insert 7 into the insertion area 17 of the magnet insertion hole 5 and pressing the convex piece 25A in the insertion area 17 toward one side in the stacking direction. This pressing deforms the convex piece 25A at least within the support area 19, and this deformed portion acts as a fulcrum, causing the convex piece 25A to rotate toward one side in the stacking direction. This rotation causes the tip 24b of the convex piece 25A to come into contact with one of the inner surfaces 11 and 13 of the magnet insertion hole 5, making the convex piece 25A a double-supported spring piece 25.

[0023] In the manufacturing method of the rotor 1 using this core 2 manufacturing method, the convex piece 25A is made into a double-supported spring piece 25 by inserting the magnet 7, which is the insert, into the magnet insertion hole 5, and the intermediate portion 24c between the tip 24b and the base end 24a of the spring piece 25 elastically contacts the magnet 7.

[0024] [Rotor] Figure 1 is a plan view of a rotor according to Embodiment 1 of the present invention. Figure 2 is an enlarged plan view showing the area around the magnet insertion hole of the rotor in Figure 1. Figure 3 is a cross-sectional view taken along line III-III of Figure 2. Figure 4 is an enlarged view showing a part of Figure 3. Figure 5 is an enlarged plan view showing the area around the magnet insertion hole of the core piece without a spring piece of the rotor in Figure 1.

[0025] As shown in Figures 1 to 4, the rotor 1 comprises a core 2, a magnet insertion hole 5, and a magnet 7, and together with the stator, constitutes a rotating electric machine.

[0026] Core 2 is the rotor core and is constructed in a columnar shape by stacking multiple core pieces 3. Each core piece 3 is a plate material punched out from magnetic steel sheet. Core 2 has a central hole 9 formed in its axial center, and multiple magnet insertion holes 5 are arranged circumferentially on its outer circumference. The circumferential direction refers to the direction along the outer circumference of the rotor 1, but also includes the direction of the approximate straight line in the polygonal approximation of the outer circumference. Core 2 includes a first core piece 3a having a spring piece 25 (described later) and a second core piece 3b without a spring piece 25.

[0027] Each magnet insertion hole 5 is formed in a substantially rectangular shape when viewed from above. The magnet insertion holes 5 are formed in each core piece 3 and penetrate through the entire core 2 in the stacking direction for inserting the magnets 7. The magnet insertion holes 5 are demarcated by radially opposing inner surfaces 11 and 13 and a circumferentially opposing inner surface 15. The stacking direction is the direction in which the core pieces 3 are stacked and is along the axis of the rotor 1. The radial direction is along the diameter of the rotor 1.

[0028] A radial recess 21 is formed on the inner surface 11, which is in the direction opposite to the inner surfaces 11 and 13. The recess 21 is concave in the radial direction to increase the gap between the inner surface 11 and the inner surface 13. Due to this recess 21, a portion of the inner surface 11 that is radially separated from the inner surface 13 forms the radial depth 21a of the recess 21. The opening width (circumferential width) of the recess 21 corresponds to the width of the magnet 7.

[0029] The magnet insertion hole 5 has a support area 19 for the magnet 7 on the inner surface 11 side, which is one side of the inner surface 11 and 13, in the radial direction which is opposite to the inner surface 11 and 13, and an insertion area 17 for the magnet 7 on the inner surface 13 side, which is the other side of the inner surface 11 and 13 relative to the support area 19.

[0030] The insertion area 17 of the magnet insertion hole 5 is the area into which the magnet 7 is inserted, extending radially from the inner surface 13 to a part of the recess 21. When the magnet 7 is inserted into the insertion area 17, one radial surface 7a is located at the boundary between the insertion area 17 and the support area 19 and is pressed by the spring piece 25. The other surface 7b of the magnet 7 is in contact with the inner surface 13 by the elasticity of the spring piece 25. The support area 19 is the area in which the spring piece 25 is housed and is provided within the recess 21.

[0031] The spring piece 25 is provided between the inner surfaces 11 of the magnet insertion hole 5 and the outer surface 14 of the magnet 7, which are opposite to each other, and holds the magnet 7 inside the magnet insertion hole 5. In this embodiment, the spring piece 25 is provided on the inner surface 11, which is one of the opposing inner surfaces 11 and 13 of the magnet insertion hole 5, and presses the magnet 7 against the inner surface 13, which is the other of the inner surfaces 11 and 13 of the magnet insertion hole 5. Note that the spring piece 25 only needs to be provided so as to hold the magnet 7 inside the magnet insertion hole 5, and may be provided on, for example, one of the opposing inner surfaces 15.

[0032] In this embodiment, the spring pieces 25 are provided at multiple locations in the stacking direction and at two locations in the circumferential direction of the magnet insertion hole 5. The number of spring pieces 25 can be set as appropriate. Each spring piece 25 is formed in a double-supported shape by the deformation of a cantilevered convex piece 25A, which will be described later. As a result, the spring piece 25 is a curved, elastic plate-like shape and has a base end 24a, a tip 24b, and an intermediate portion 24c. The spring piece 25 has a constant width and thickness from the base end 24a to the tip 24b, but it is possible to vary either the width or the thickness, or both.

[0033] In this embodiment, the spring piece 25 is formed by the deformation of a single convex piece 25A, but it may also be formed by the deformation of multiple convex pieces 25A. For example, by deforming multiple convex pieces 25A while they are stacked on top of each other, a spring piece 25 consisting of multiple plate-like bodies formed by the deformation of multiple convex pieces 25A is formed in a double-supported manner.

[0034] The base end 24a of the spring piece 25 is integrated with the inner surface 11, which is one of the inner surfaces 11 and 13 of the magnet insertion hole 5. In this embodiment, the base end 24a of the spring piece 25 is integrated with the inner surface 11 of the magnet insertion hole 5 of the first core piece 3a. As a result, the base end 24a of the spring piece 25 is held by the inner surface 11 of the magnet insertion hole 5. Radial slits 23 are provided on both sides of the spring piece 25 in the circumferential direction.

[0035] The tip 24b of the spring piece 25 is in contact with the inner surface 11, which is one of the inner surfaces 11 and 13 of the magnet insertion hole 5. The tip 24b is the part that contacts the inner surface 11 and may include a further extended portion. In this case, the portion that extends from the part that contacts the inner surface 11 may extend away from the inner surface 11 by bending or the like, or extend along the inner surface 11. Also, if the spring piece 25 consists of multiple plate-like bodies, the tips of some or all of the plate-like bodies will be in contact with the inner surface 11.

[0036] The contact of the tip 24b of the spring piece 25 with the inner surface 11 is carried out in a manner that does not interfere with adjacent spring pieces 25 in the stacking direction, so that the tip 24b of each spring piece 25 contacts the inner surface 11 of the second core piece 3b. Specifically, as shown in Figures 4 and 5, the inner surface 11 of the second core piece 3b is provided with radial receiving recesses 23A corresponding to the spring pieces 25 that receive the tips 24b of the spring pieces 25.

[0037] The tip 24b of the spring piece 25 enters the receiving recess 23A and contacts the back part 23Aa of the receiving recess 23A. Therefore, the spring piece 25 is supported in a double-supported manner in the magnet insertion hole 5 by the contact of the tip 24b with the inner surface 11 and the integration of the base end 24a.

[0038] In this embodiment, the radial positions of the tip 24b and the base 24a of the spring piece 25 coincide. However, the radial positions of the tip 24b and the base 24a of the spring piece 25 may be made different, for example, by omitting the receiving recess 23A or by setting the receiving recess 23A to a deeper position.

[0039] The intermediate portion 24c between the base end 24a and the tip end 24b of the spring piece 25 bulges out and elastically contacts the inner surface 11 of the magnet insertion hole 5 and the outer surface 14 of the magnet 7, which in this embodiment is the outer surface 14 of the magnet 7. The intermediate portion 24c in this embodiment includes a bent portion 25a, an extended portion 25c, and a deformed portion 25b.

[0040] The curved portion 25a is located between the base end 24a and the tip end 24b, closer to the tip end 24b. In this embodiment, the curved portion 25a has an arc-shaped cross-section and extends with a constant curvature to the tip end 24b of the spring piece 25. However, the curved portion 25a does not need to be arc-shaped, and its curvature does not need to be constant.

[0041] An extended portion 25c is provided on the base end 24a side relative to the curved portion 25a. A contact portion 25d is located at the boundary between the curved portion 25a and the extended portion 25c. The contact portion 25d is the part of the spring piece 25 that elastically contacts the magnet 7 in the middle portion 24c. The contact portion 25d may also be located within the curved portion 25a. Furthermore, if the spring piece 25 consists of multiple plate-like bodies, only the contact portion 25d of the plate-like body facing the magnet 7 elastically contacts the magnet 7.

[0042] The extending portion 25c is a portion extending from the curved portion 25a to the deformed portion 25b. The extending portion 25c of the present embodiment extends straight, but it may also extend while curving. This extending portion 25c is inclined so as to gradually approach the inner surface 11 toward the deformed portion 25b from the curved portion 25a.

[0043] The deformed portion 25b is provided between the proximal end 24a of the spring piece 25 and the extending portion 25c. The deformed portion 25b positions the extending portion 25c so as to fall in the insertion direction with respect to the proximal end 24a of the spring piece 25. In the present embodiment, the radius of curvature of the deformed portion 25b is smaller than the radius of curvature of the curved portion 25a. However, the radii of curvature of the deformed portion 25b and the curved portion 25a can be set as appropriate.

[0044] Such a spring piece 25 receives a pressing force from the magnet 7 in a state of being held on both sides with respect to the inner surface 11 of the magnet insertion hole 5. Thereby, the spring piece 25 exhibits a biasing force against the magnet 7 through the contact portion 25d of the intermediate portion 24c and elastically contacts. Thereby, the magnet 7 is pressed against and held on the inner surface 13 of the magnet insertion hole 5.

[0045] [Rotor Core] FIG. 6 is an enlarged plan view showing the periphery of the magnet insertion hole before inserting the magnet in FIG. 2, and FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6. FIG. 8 is an enlarged view showing a part of FIG. 7.

[0046] The core 2A before inserting the magnet 7 in FIGS. 6 to 8 constitutes the laminate of the present embodiment. Note that the laminate may be a block for constituting a core by laminating a plurality of layers. Such a core 2A has a columnar portion formed by laminating a plurality of core pieces 3 as a main body portion 2Aa, and has a convex piece 25A before becoming a spring piece 25 in the magnet insertion hole 5 formed in the main body portion 2Aa.

[0047] Each convex piece 25A has a curved portion 25a and an extending portion 25c according to the spring piece 25, but does not have a deformed portion 25b. Otherwise, it has the same configuration as the core 2 after inserting the magnet 7.

[0048] As a result, the convex piece 25A is provided on the inner surface 11, which is one of the inner surfaces 11 and 13 of the magnet insertion hole 5, and extends toward the other of the inner surfaces 11 and 13. Specifically, the convex piece 25A has a base end 24a that is integrally cantilevered on the inner surface 11 of the magnet insertion hole 5 and projects radially from the support region 19 to the insertion region 17. A part of the bending portion 25a and the extending portion 25c adjacent thereto are located within the insertion region 17 of this convex piece 25A.

[0049] The bending portion 25a is directed toward one side in the stacking direction, which is the front in the insertion direction of the magnet 7, and the center of curvature is located on one side in the stacking direction. This bending portion 25a is generally formed as a 1 / 4 arc in a free state.

[0050] The size of the bending portion 25a is formed in relation to the support region 19. That is, the bending portion 25a is configured such that the height h from the tip 24b to the contact portion 25d (the height from the tip 24b to the contact portion 25d in the direction orthogonal to the tangent of the contact portion 25d) corresponds to the width b of the support region 19 in the radial direction. In this embodiment, the height h from the tip 24b to the contact portion 25d is set to be slightly larger than the width b of the support region 19.

[0051] [Method for manufacturing a rotor] In the method for manufacturing the rotor 1 of this embodiment, as shown in FIG. 7, a plurality of core pieces 3 are laminated to form a core 2A as a laminate having a plurality of convex pieces 25A in the stacking direction. For example, the first core piece 3a and the second core piece 3b are mixed, and the first core piece 3a is laminated every time a predetermined number of the second core pieces 3b are laminated. The predetermined number of the second core pieces 3b may be either a fixed number or different numbers. Further, when the spring piece 25 is formed by deforming a plurality of convex pieces 25A, a plurality of the first core pieces 3a are continuously laminated.

[0052] FIG. 9 is an enlarged cross-sectional view showing the initial stage of inserting the magnet into the magnet insertion hole of FIG. 7.

[0053] Next, as shown in Figure 9, the magnet 7 is inserted into the insertion area 17 of the magnet insertion hole 5 of the core 2A. That is, when the magnet 7 is inserted into the insertion area 17 of the magnet insertion hole 5, the end face of the magnet 7 comes into contact with the vicinity of the contact area 25d of the extended portion 25c and the curved portion 25a of the convex piece 25A, which are located within the insertion area 17. If the magnet 7 is inserted further in this state, the magnet 7 presses the convex piece 25A toward one side in the stacking direction (downward in the figure) within the insertion area 17. This pressing deforms the convex piece 25A within the support area 19, forming the deformed portion 25b.

[0054] The deformable portion 25b is not shaped before deformation. Therefore, the deformable portion 25b is formed on the base end 24a side where the bending moment becomes large due to the external force caused by inserting the magnet 7 into the insertion area 17. It is also possible to specify the deformable portion 25b by relatively narrowing the width of a part of the extended portion 25c or relatively thinning its thickness.

[0055] During the formation of this deformed portion 25b, the lower end of the magnet 7 slides in contact with the extended portion 25c of the convex piece 25A, and as the magnet 7 is inserted, the extended portion 25c tilts to one side in the stacking direction. As a result, the contact point of the magnet 7 with the convex piece 25A shifts towards the curved portion 25a as the formation of the deformed portion 25b progresses.

[0056] This causes the convex piece 25A to rotate so that it tilts to one side in the stacking direction, from the extended portion 25c to the curved portion 25a, with the deformable portion 25b (the part that deforms) as the pivot point. This rotation causes the tip 24b of the convex piece 25A to come into contact with the inner surface 11, which is one of the inner surfaces 11 and 13 of the magnet insertion hole 5, thereby transforming the cantilevered convex piece 25A into a double-supported spring piece 25, as shown in Figures 4 and 9. Thus, the formation of the deformable portion 25b can be carried out smoothly.

[0057] As the insertion of the magnet 7 progresses, the magnet 7 is pressed against the inner surface 13 of the magnet insertion hole 5, thereby enabling accurate insertion into the insertion area 17. In other words, the magnet 7 reduces the initial insertion precision required for the magnet insertion hole 5 into the insertion area 17, making the insertion process easier.

[0058] The formed spring piece 25 has an intermediate portion 24c contact portion 25d elastically in contact with the magnet 7, allowing it to hold the magnet 7 in place. Once the magnet 7 is fully inserted into the magnet insertion hole 5, as shown in Figure 3, the magnet 7 can be held in place by the sequentially formed spring pieces 25 in contact with the inner surface 13 of the magnet insertion hole 5.

[0059] Thus, in this embodiment, since the insert is a magnet 7, the manufacturing of the core 2 having the spring piece 25 is the same as the manufacturing of the rotor 1. However, if the insert is a jig with the same shape as the magnet 7, the core 2 having the spring piece 25 is manufactured, the jig is removed from the core 2, and then the magnet 7 is inserted into the magnet insertion hole 5.

[0060] As described above, in this embodiment, the rotor 1 has a double-supported configuration in which the base end 24a of the spring piece 25 is held by the inner surface 11 of the magnet insertion hole 5, and the tip 24b of the spring piece 25 abuts against the inner surface 11 of the magnet insertion hole 5, and the intermediate portion 24c between the base end 24a and the tip 24b bulges out and elastically contacts the outer surface 14 of the magnet 7.

[0061] Therefore, when the intermediate portion 24c receives pressure from the magnet 7, the tip 24b and base 24a on both sides are received by the inner surface 11 of the magnet insertion hole 5, and elastic energy can be reliably stored in the intermediate portion 24c. As a result, the spring piece 25 exerts a biasing force and reliably elastically contacts the outer surface 14 of the magnet 7, holding the magnet 7 inside the magnet insertion hole 5.

[0062] Therefore, in this embodiment, the holding force of the magnet 7 can be improved by the double-supported spring piece 25. Alternatively, the magnet 7 can be easily inserted while maintaining (without improving) the holding force. Furthermore, since a separate component such as resin or a spring to hold the magnet 7 is not required, costs can be reduced. In addition, since resin is not used to fix the magnet 7, the heat resistance of the rotor 1 can be improved.

[0063] Furthermore, since the spring piece 25 has a curved portion 25a from the contact portion 25d that elastically contacts the magnet 7 to the tip 24b, it is easier to generate a biasing force on the magnet 7, and the holding force of the magnet 7 can be improved more reliably.

[0064] Furthermore, since the spring pieces 25 are provided at multiple locations in the axial direction of the magnet insertion hole 5, the magnet 7 can be securely fixed in the magnet insertion hole 5.

[0065] In this embodiment, by inserting a magnet 7 into the magnet insertion hole 5 of the core 2A, which is a laminate having a protruding piece 25A, the protruding piece 25A is pressed to one side in the lamination direction in the insertion area 17. This pressing deforms the protruding piece 25A within the support area 19, allowing it to be formed into a double-supported spring piece 25.

[0066] Therefore, in this embodiment, the double-supported spring piece 25 can be easily formed. Furthermore, by inserting the magnet 7 into the magnet insertion hole 5, it can be guided to the insertion area 17 in accordance with the formation of the spring piece 25, and the formed spring piece 25 can hold the magnet 7 more securely.

[0067] Furthermore, in this embodiment, the spring piece 25 is formed and the magnet 7 is held in place by inserting the magnet 7 into the magnet insertion hole 5, so a rotor 1 with the magnet 7 fixed in the magnet insertion hole 5 can be easily obtained.

[0068] Figure 10 is an enlarged cross-sectional view showing a part of the rotor according to Embodiment 2 of the present invention. In Embodiment 2, the basic configuration is the same as that of Embodiment 1, so the same reference numerals are used to indicate the corresponding components, and redundant explanations are omitted.

[0069] The rotor 1 in this embodiment has a plurality of receiving portions 27 in the magnet insertion hole 5. Each receiving portion 27 protrudes into the support area 19 and faces the tip 24b of the double-supported spring piece 25 in the stacking direction.

[0070] In other words, the core 2 includes a first core piece 3a and a second core piece 3b, as well as a third core piece 3c. The third core piece 3c omits the receiving recess 23A and has a relative radial projection 27A. The receiving portion 27 is formed by the continuous arrangement of these projections 27A in the stacking direction. The receiving portion 27 may also be formed by a single projection 27A.

[0071] Since the receiving portion 27 receives the tip 24b of the spring piece 25 of the double-supported body in the stacking direction, it suppresses displacement of the tip of the spring piece 25 in the stacking direction when holding the magnet 7. As a result, the rigidity of the spring piece 25 is improved, and the force pressing the magnet 7 against the inner surface 13 can be improved.

[0072] Furthermore, the same effects and advantages as in Example 1 can be achieved in Example 2.

[0073] Figure 11 is an enlarged cross-sectional view showing a part of the rotor according to Embodiment 3 of the present invention. Figure 12 is an enlarged view showing a part of Figure 11. Since Embodiment 3 has the same basic configuration as Embodiment 2, the corresponding components are indicated by the same reference numerals, and redundant explanations are omitted.

[0074] In this embodiment, the rotor 1 has multiple bent portions 25a in each spring piece 25. The number of bent portions 25a in each spring piece 25 is two, but can be set as appropriate. One bent portion 25aa is located on the tip 24b side of the spring piece 25, and the other bent portion 25ab is located on the base end 24a side of the spring piece 25.

[0075] One of the curved portions 25aa does not continue to the tip 24b of the spring piece 25, but is continuous with the extended portion 25e on the tip 24b side, which extends straight in the radial direction. The extended portion 25e is located between the tip 24b of the spring piece 25 and the curved portion 25aa.

[0076] The other curved portion 25ab is continuous with the extended portion 25c on the base end 24a side, which extends straight in the radial direction. The extended portion 25c is located between the base end 24a and the curved portion 25ab of the spring piece 25.

[0077] The curved portions 25aa and 25ab are formed in a concave shape so as to recess into the support area 19 relative to the insertion area 17, and are smooth and continuous without any edges.

[0078] The spring piece 25 is double-supported, similar to Embodiment 2, and its tip 24b and the extended portion 25e on the tip side are supported in the stacking direction by the receiving portion 27. Alternatively, the spring piece 25 may be configured not to be supported in the stacking direction by the receiving portion 27, similar to Embodiment 1.

[0079] Because the spring piece 25 has multiple bent portions 25aa and 25ab that contact the magnet 7, the load is distributed, improving shape retention and increasing the force pressing the magnet 7 against the inner surface 13.

[0080] Furthermore, the same effects and advantages as those in Examples 1 and 2 can be achieved in Example 3.

[0081] Figure 13 is an enlarged cross-sectional view showing a part of the rotor according to Embodiment 4 of the present invention. Figure 14 is an enlarged view showing a part of Figure 13. Since Embodiment 4 has the same basic configuration as Embodiment 1, corresponding components are indicated by the same reference numerals, and redundant explanations are omitted.

[0082] As shown in Figures 13 and 14, the rotor 1 of Embodiment 4 includes a tip-side extension 25e that extends straight between the tip 24b and the curved portion 25a of the spring piece 25. The curved portion 25a is formed in an arc, but its radius of curvature is smaller than that of Embodiment 1.

[0083] The spring piece 25 is double-supported, similar to that in Embodiment 1, and its tip 24b contacts the inner surface 11 of the magnet insertion hole 5 with the extended portion 25e inclined. It is also possible to apply the spring piece 25 of this embodiment to the structure of Embodiment 2.

[0084] In this embodiment 4, the same effects and advantages as in embodiment 1 can be achieved.

[0085] Figure 15 is an enlarged cross-sectional view showing a part of the rotor according to Embodiment 5 of the present invention. Figure 16 is an enlarged cross-sectional view showing the insertion of a magnet into the magnet insertion hole of Embodiment 5. Since Embodiment 5 has the same basic configuration as Embodiment 1, corresponding components are indicated by the same reference numerals, and redundant explanations are omitted.

[0086] In this embodiment, the rotor 1 is held by the magnet 7, as shown in Figure 15. Specifically, the base end 24a of the spring piece 25 is held by the outer surface 14 of the magnet 7, the tip 24b is in contact with the outer surface 14 of the magnet 7, and the middle portion 24c is elastically in contact with the inner surface 11 of the magnet insertion hole 5.

[0087] The base end 24a of the spring piece 25 extends straight radially and is inserted into the groove 29 of the magnet 7. A portion of the base end 24a of the spring piece 25 protrudes radially from the outer surface 14 of the magnet 7. As a result, the base end 24a of the spring piece 25 is held by the outer surface 14 of the magnet 7.

[0088] The base end 24a of the spring piece 25 is fixed to the magnet 7 by being inserted into the groove 29, or is held in the magnet 7 with enough play to prevent the spring piece 25 from coming off when inserted into the magnet insertion hole 5. The groove 29 can be formed in the magnet 7 by processing with a cutter or the like, or formed during the molding of the magnet 7. When fixing the spring piece 25 to the magnet 7, adhesive may be used. In this case, the groove 29 can be omitted.

[0089] The tip 24b of the spring piece 25 is in contact with the outer surface 14 of the magnet 7. As a result, the spring piece 25 is double-supported. The middle portion 24c of this double-supported spring piece 25 elastically contacts the inner surface 11 of the magnet insertion hole 5, holding the magnet 7 inside the magnet insertion hole 5.

[0090] When manufacturing such a rotor 1, as shown in Figure 16, the magnet 7 is inserted into the insertion area 17 of the magnet insertion hole 5 of the core 2. At this time, a protruding piece 25A protrudes radially from the magnet 7, and the portion from a part of the extended portion 25c of the protruding piece 25A to the curved portion 25a is located outside the magnet insertion hole 5. The protruding piece 25A has the same configuration as in Embodiment 1, but since it protrudes from the magnet 7, the curved portion 25a is oriented to the other side in the stacking direction, which is behind the insertion direction of the magnet 7.

[0091] As the magnet 7 is inserted further into the magnet insertion hole 5, the extended portion 25c and the area near the contact portion 25d of the curved portion 25a of the convex piece 25A, which is located outside the magnet insertion hole 5, come into contact with the core 2. If the magnet 7 is inserted further in this state, the convex piece 25A outside the magnet insertion hole 5 is pressed by the core 2 to the other side in the stacking direction (upwards in the figure). This pressing deforms the convex piece 25A, forming a deformed portion 25b.

[0092] The deformable portion 25b does not have a defined shape before deformation, but it may be folded or made thinner than other parts. In this embodiment, the deformable portion 25b is formed on the base end 24a side where the bending moment becomes large due to the external force caused by the insertion of the magnet 7, similar to embodiment 1.

[0093] During the formation of the deformed portion 25b, the convex piece 25A is rotated so that it tilts to the other side in the stacking direction, from the extended portion 25c to the curved portion 25a, using the deformed portion 25b (the part that deforms) as a pivot point. This rotation causes the tip 24b of the convex piece 25A to come into contact with the outer surface 14 of the magnet 7, forming a double-supported spring piece 25.

[0094] The formed spring piece 25 has its intermediate portion 24c contact portion 25d elastically in contact with the inner surface 11 of the magnet insertion hole 5, allowing it to hold the magnet 7 inside the magnet insertion hole 5. Once the magnet 7 is fully inserted into the magnet insertion hole 5, the magnet 7 can be held inside the magnet insertion hole 5 by the multiple spring pieces 25, as shown in Figure 15.

[0095] In this embodiment, the spring piece 25 is held by the magnet 7. Specifically, the base end 24a of the spring piece 25 is held by the outer surface 14 of the magnet 7, the tip 24b is in contact with the outer surface 14 of the magnet 7, and the middle portion 24c is elastically in contact with the inner surface 11 of the magnet insertion hole 5.

[0096] This embodiment, with its configuration, can achieve the same effects and advantages as in Embodiment 1.

[0097] [Modified Example] Figure 17 is an enlarged cross-sectional view showing a modified example of Embodiment 5, in which a magnet is inserted into the magnet insertion hole.

[0098] In the modified example shown in Figure 17, the magnet 7 is divided into multiple segmented pieces 31 in the insertion direction, and the base end 24a of the spring piece 25 (convex piece 25A) is sandwiched between the segmented pieces 31. The segmented pieces 31 of the magnet 7 and the base end 24a of the spring piece 25 (convex piece 25A) may be integrated by adhesive or the like, or they may be held integrally by a jig without being integrated, and then inserted into the magnet insertion hole 5. If the segmented pieces 31 and the spring piece 25 are not integrated, specifically, when inserting the magnet 7 into the magnet insertion hole 5, the magnet 7 and the spring piece 25 (convex piece 25A) are supported by a magnet insertion jig (not shown).

[0099] Therefore, in this modified example as well, by inserting the magnet 7 into the magnet insertion hole 5, the spring piece 25 can hold the magnet 7 in place within the magnet insertion hole 5, and the same effects as in Example 1 can be achieved.

[0100] Furthermore, if the divided piece 31 and the spring piece 25 are not integrated, the base end 24a of each spring piece 25 receives the divided piece 31 of the magnet 7 in the insertion direction, and the tip 24b of each spring piece 25 abuts radially against the divided piece 31 received by the base end 24a. This allows the divided piece 31 to be held in the magnet insertion hole 5 by the double-supported spring pieces 25. In this case, the moment generated by the divided piece 31 of the magnet 7 from each spring piece 25 presses the tip 24b of each spring piece 25 against the divided piece 31, allowing the divided piece 31 to be held more securely in the magnet insertion hole 5.

[0101] 1 Rotor core 1A Laminated iron core (laminated body) 3 Iron core piece 5 Magnet insertion hole 7 Magnet (insertion body) 17 Insertion area 19 Support area 21 Recess 25 Spring piece 25a Bent part 25b Deformed part 25c Base end extension part 25d Contact part (intermediate part) 25e Tip extension part 27 Receiving part

Claims

A core made by stacking multiple core pieces, The core has magnet insertion holes provided in the stacking direction of the core pieces, The magnet inserted into the aforementioned magnet insertion hole, The device comprises a spring piece provided between the inner surfaces of the mutually opposing magnet insertion holes and the outer surface of the magnet, which holds the magnet within the magnet insertion hole. The spring piece is double-supported, having a base end held by one of the inner surfaces of the magnet insertion hole and the outer surface of the magnet, and a tip that abuts against the one of the inner surfaces of the magnet insertion hole and the outer surface of the magnet, with the intermediate portion between the base end and the tip bulging out and elastically contacting the other of the inner surfaces of the magnet insertion hole and the outer surface of the magnet. rotor. 　 A rotor according to claim 1, The spring piece has its base end held against the inner surface of the magnet insertion hole, its tip in contact with the inner surface of the magnet insertion hole, and its middle portion elastically in contact with the outer surface of the magnet. rotor. 　 A rotor according to claim 2, The spring piece has a curved portion from the contact portion that elastically contacts the inner surface of the magnet insertion hole or the outer surface of the magnet to the tip. rotor. 　 A rotor according to claim 2, The spring pieces are provided at each of the multiple locations in the axial direction of the magnet insertion hole, rotor. 　 A rotor according to claim 2, The magnet insertion hole has a receiving portion that receives the tip of the spring piece in the stacking direction. rotor. 　 A rotor according to claim 1, The spring piece has its base end held by the outer surface of the magnet, its tip in contact with the outer surface of the magnet, and its middle portion elastically in contact with the inner surface of the magnet insertion hole. rotor. 　 The main body consists of multiple core pieces stacked together, The magnet insertion holes provided in the stacking direction of the core piece of the main body, The magnet insertion hole comprises a convex piece provided on one of the opposing inner surfaces and extending toward the other inner surface, The magnet insertion hole has a support area for the insert on one side of the inner surface and an insertion area for the insert on the other side of the inner surface relative to the support area. The convex piece is cantilevered, having an integral base end on one side of the inner surface of the magnet insertion hole, and protrudes from the support area to the insertion area, having a curved portion directed toward one side in the stacking direction and an extended portion between the curved portion and the base end. Laminated structure. 　 The laminate according to claim 7, The magnet insertion hole includes the inner surface recesses in opposing directions, The support area is provided within the recess, Laminated structure. 　 A method for manufacturing a core using the laminate according to claim 7, Insert the insert into the insertion area of ​​the magnet insertion hole and press the protrusion toward one side in the stacking direction within the insertion area. By pressing, the protrusion is deformed at least within the support area, and the deformed portion is used as a fulcrum to rotate the protrusion toward one side in the stacking direction. The aforementioned rotation causes the tip of the protrusion to contact one of the inner surfaces of the magnet insertion hole, thereby forming a double-supported spring piece. Core manufacturing method. 　 A method for manufacturing a rotor using the core manufacturing method of claim 9, By inserting the magnet, which is the insert, into the magnet insertion hole, the convex piece becomes the double-supported spring piece, and the intermediate portion between the tip and base of the spring piece elastically contacts the magnet. A method for manufacturing a rotor.

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