Manufacturing method for rotor of rotary electric machine, manufacturing apparatus, and rotary electric machine

Abstract

The present invention is a manufacturing method for a rotor of a rotary electric machine comprising a core formed by laminating steel plates, and a magnet inserted into a through-hole of the core, the method performing: a heating step for heating the magnet; and an insertion step for inserting the heated magnet into the through-hole filled with a thermosetting resin.

Description

Rotor manufacturing method for rotating electric machine, manufacturing equipment, rotating electric machine

[0001] The present invention relates to a method for manufacturing a rotor for a rotating electric machine, a manufacturing device, and a rotating electric machine.

[0002] The following Patent Document 1 discloses a technology in which an adhesive for fixing a magnet is inserted into a rotor core, a magnet is then inserted, and the magnet is clamped with electrodes and electricity is passed through to heat the magnet and harden the adhesive.

[0003] Japanese Patent Application Laid-Open No. 2022-52692

[0004] In the technology described in Patent Document 1, the viscosity of the adhesive is reduced until it hardens, which creates the problem of the adhesive leaking out through the gaps between the laminated steel plates that make up the rotor core.

[0005] A method for manufacturing a rotor for a rotating electric machine having a core made of laminated steel plates and a magnet inserted into a through hole of the core, the method comprising: a heating step for heating the magnet; and an insertion step for inserting the heated magnet into the through hole filled with a thermosetting resin.

[0006] It is possible to provide a manufacturing method for a rotor of a rotating electric machine, a manufacturing device, and a rotating electric machine that are cost-reduced and have improved reliability.

[0007] 1 is a cross-sectional view showing the overall structure of a rotating electric machine; FIG. 2 is an explanatory diagram of a rotor of a rotating electric machine and a pressure jig according to one embodiment of the present invention; FIG. 3 is an exploded view of the structure of the pressure jig in FIG. 2; FIG. 4 is an explanatory diagram of a magnet heating holder according to one embodiment of the present invention; FIG. 5 is an explanatory diagram of a pressure generating jig according to one embodiment of the present invention; FIG. 6 is an explanatory diagram of a magnet insertion guide according to one embodiment of the present invention;

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (One embodiment and overall configuration) (FIG. 1) A rotating electric machine 100 has a housing 1, a shaft 2, a rotor 3, and a stator 4. The stator 4 is mechanically fixed to the housing 1. The rotor 3 is disposed on the inner diameter side of the stator 4, and the shaft 2 is provided in the center of the rotor 3. The shaft 2 is rotatably supported at both axial ends by a plurality of bearings 5 ​​provided in the housing 1.

[0011] (Fig. 2) Fig. 2 is a diagram illustrating the configuration of manufacturing equipment that heats and inserts magnets to be inserted into the rotor 3 of the rotating electric machine 100 of Fig. 1. The manufacturing equipment for the rotor 3 of the rotating electric machine 100 includes a magnet heating holder 6 and a core pressing jig. The core pressing jig includes a center shaft 7, a magnet insertion guide 8, a pressure generating jig 11, and a core stand 12.

[0012] The rotor 3 has a core 3a. The core 3a is formed by laminating a plurality of steel plates 13 (FIG. 9). In the manufacturing method of the present invention, first, a heating step is performed to heat the magnets 3c before inserting them into the through holes 3b of the core 3a, and then a pressing step is performed to fill the gaps between the steel plates 13 by pressing the plurality of steel plates 13 in the axial direction.

[0013] The center shaft 7 is disposed radially inward in the magnet heating holder 6. Fig. 3, which will be described later, illustrates Fig. 2 with the center shaft 7 removed.

[0014] (Figs. 3 to 7) The magnet heating holder 6 is an annular magnet heating jig that holds and heats the magnet 3c before it is inserted into the core 3a. The magnet heating holder 6 has through holes 6a and 6b. The magnet heating holder 6 is arranged coaxially with the center shaft 7 (Fig. 2) that presses the core 3a in the axial direction.

[0015] The through-hole 6a has a fitting portion 6c. The through-hole 6b is a hole for inserting the magnet 3c and is larger than the cross-sectional size of the magnet 3c. The fitting portion 6c fits into the main body portion 11b of the pressure generating jig 11, allowing the central axis to be aligned with that of the core pressure jig.

[0016] The multiple magnets 3c inserted into the magnet heating holder 6 each have a small volume, resulting in a small heat capacity, and therefore the heat capacity required to harden the thermosetting resin 15 filled into the core 3a is insufficient. Therefore, all of the magnets 3c inserted into the core 3a are simultaneously heated. This reduces costs. In the heating process, the magnets 3c are heated to at least the glass transition temperature at which the thermosetting resin 15 (FIGS. 10 and 11) hardens. For example, the magnets 3c are heated to a temperature between two and three times the glass transition temperature.

[0017] As a method for heating the magnets 3c inserted in the magnet heating holder 6, for example, a method of heating the entire magnet heating holder 6 using high-frequency heating, or a method of passing a direct current through each magnet 3c to perform electrical heating may be adopted.

[0018] The pressure generating jig 11 has a protruding portion 11a that protrudes toward the magnet insertion guide 8 in the axial direction and a main body portion 11b that fits into the fitting portion 6c of the magnet heating holder 6. The protruding portion 11a passes through the first through hole 8a of the magnet insertion guide 8 and comes into contact with the peripheral portion 14 of the shaft hole 2a of the core 3a. The protruding portion 11a also aligns the central axes of the core 3a, the magnet insertion guide 8, and the pressure generating jig 11. The diameter of the protruding portion 11a of the pressure generating jig 11, the diameter of the first through hole 8a, and the diameter of the shaft hole 2a of the core 3a are the same. In this way, in the pressing process, the protruding portion 11a presses the peripheral portion 14 in the axial direction, thereby filling gaps between the multiple steel plates that occur in the core 3a.

[0019] The peripheral edge 14 of the shaft hole 2a of the core 3a is at least a part of the annular region from the radially innermost point or side on the edge of the through hole 3b to the edge of the shaft hole 2a.

[0020] By fitting the main body 11b into the fitting portion 6c of the magnet heating holder 6, the centers of the magnet heating holder 6 and the pressure generating jig 11 can be aligned. Furthermore, when the magnet 3c is pushed out of the magnet heating holder 6 and inserted into the magnet insertion guide 8 and core 3a by dropping it vertically, the main body 11b can change the drop height of the magnet 3c by changing its vertical thickness, thereby adjusting the free fall distance of the magnet 3c. This helps ensure reliable insertion of the magnet 3c into the magnet insertion guide 8 and core 3a according to its length.

[0021] The magnet insertion guide 8 has a first through hole 8a and a second through hole 8b. The protrusion 11a of the pressure generating jig 11 is inserted into the first through hole 8a. The second through hole 8b is a hole through which the magnet 3c passes after being removed from the magnet heating holder 6. The cross-sectional size of the second through hole 8b is larger than the cross-sectional size of the magnet 3c and smaller than the cross-sectional size of the through hole 3b of the core 3a.

[0022] The second through-hole 8b also has a tapered portion 8c on the magnet 3c insertion opening side. The tapered portion 8c helps ensure reliable insertion during the insertion process of inserting the heated magnet 3c from the magnet heating holder 6 into the second through-hole 8b filled with thermosetting resin 15 (FIG. 10). The tapered portion 8c may be provided only on the side of the magnet insertion guide 8 where the magnet 3c is inserted, or may be provided on the opposite side.

[0023] The core 3a has a shaft hole 2a through which the center shaft 7 (FIG. 2) can pass, and a through hole 3b into which the magnet 3c is inserted. The magnet 3c inserted into the through hole 3b is fixed to the core 3a when the thermosetting resin 15 (FIGS. 10 and 11) filled in the through hole 3b hardens.

[0024] The core stand 12 is a stand for placing the core 3a on the core pressing jig. The core stand 12 has a protruding portion 12a that protrudes from the center, perpendicular to the plane. The core 3a is placed on the core stand 12 by inserting the protruding portion 12a of the core stand 12 into the shaft hole 2a. The core 3a is placed on the magnet insertion guide 8 on the surface opposite to the surface on the core stand 12 where it is placed.

[0025] When the core 3a is pressed by the core pressing jig and the magnet 3c inserted into the magnet heating holder 6 is heated, and the core pressing jig and the magnet heating holder 6 are combined, the through hole 3b of the core 3a, the second through hole 8b of the magnet insertion guide 8, and the through hole 6b of the magnet heating holder 6 are in the same position in the axial direction. As a result, the magnet 3c heated in the through hole 6b of the magnet heating holder 6 passes through the second through hole 8b of the magnet insertion guide 8 and is inserted into the through hole 3b of the core 3a.

[0026] (Manufacturing Process) (FIG. 9) A flowchart of the manufacturing process of the rotor 3 of the rotating electrical machine 100 of the present invention will be described. The pressing processes of steps S1 and S2 are performed in parallel with the heating processes of steps S3 and S4. Steps S5 to S7 are insertion processes.

[0027] In step S1, the core 3a is placed on the core pressing jig. In step S2, the core 3a is pressed in the axial direction by the core pressing jig, and when the pressing process is completed, the through holes 3b of the core 3a are filled with thermosetting resin 15. In step S3, the magnets 3c are inserted into the magnet heating holder 6. In step S4, the magnet heating holder 6 is heated by high-frequency heating, thereby simultaneously heating the magnets 3c inserted into the through holes 6b of the magnet heating holder 6. In step S5, the heated magnet heating holder 6 is placed on the core pressing jig on which the core 3a is placed. In step S6, the multiple magnets 3c heated from the magnet heating holder 6 are simultaneously inserted into the core 3a. In step S7, the pressing jig is removed from the core 3a, and the flowchart ends.

[0028] (Figs. 10 and 11) The process of inserting a heated magnet 3c into the core 3a will be described. Fig. 10(a) shows the core 3a before the magnet 3c is inserted, and shows the state in which the core 3a is pressurized in the axial direction by the pressure generating jig 11. In Fig. 10(b), the through hole 3b is filled with thermosetting resin 15, which is a liquid adhesive.

[0029] In Figure 10(c), a heated magnet 3c is inserted via a magnet insertion guide 8 into a through-hole 3b filled with thermosetting resin 15. At this time, the viscosity of the thermosetting resin 15 around the magnet 3c has decreased due to contact with the heated magnet 3c. The area 15a where the viscosity of the thermosetting resin 15 has decreased is shown.

[0030] 11(a) shows a state in which the magnet 3c is inserted into the through-hole 3b, and the thermosetting resin 15 with reduced viscosity flows around the magnet 3c, so that the magnet 3c is completely inserted into the through-hole 3b. The viscosity of the entire thermosetting resin 15 filling the through-hole 3b is low.

[0031] In Figure 11(b), the thermosetting resin 15 filled in the through-hole 3b absorbs heat from the magnet 3c and hardens rapidly from the periphery of the magnet 3c. The state of the thermosetting resin 15 hardening is shown as hardened area 15b. In Figure 11(c), all of the thermosetting resin 15 filled in the through-hole 3b has hardened.

[0032] By adopting the manufacturing process of the present invention, the core 3a is fully pressurized in the axial direction by the core pressure jig, and the time during which the viscosity of the thermosetting resin 15 decreases is much shorter than in the past, so that it is possible to prevent the low-viscosity thermosetting resin 15 from leaking out from between the steel plates of the core 3a, thereby improving reliability.

[0033] Furthermore, since the thermosetting resin 15 does not leak out of the through hole 3b, the thermosetting resin 15 is always present between the through hole 3b in the core 3a and the magnet 3c, reducing variations in the adhesion of the magnet 3c.

[0034] Furthermore, the process of scraping off the thermosetting resin 15 that leaks to the outside is eliminated, and the curing time of the thermosetting resin 15 can also be shortened, so that a heating furnace is no longer necessary and equipment costs are reduced, thereby contributing to cost reduction.

[0035] Furthermore, in order to improve the output of the rotating electric machine 100, the gap between the magnet 3c and the through hole 3b may be further narrowed. This reduces the viscosity of the thermosetting resin 15, and since there is no gap between the steel plates due to the application of pressure, the thermosetting resin 15 quickly hardens, thereby reducing the variation in adhesion of the magnet 3c while also improving output.

[0036] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0037] (1) A method for manufacturing a rotor for a rotating electric machine including a core 3a made of laminated steel plates and magnets 3c inserted into through holes 3b of the core 3a, the method comprising a heating step for heating the magnets 3c, and an insertion step for inserting the heated magnets 3c into the through holes 3b filled with thermosetting resin 15. By doing so, it is possible to provide a rotor 3 for a rotating electric machine 100 with reduced cost and improved reliability.

[0038] (2) In the heating step, the magnet is heated to at least the glass transition temperature at which the thermosetting resin hardens. By doing so, when the magnet 3c is inserted into the through hole 3b, the thermosetting resin 15 can be rapidly hardened.

[0039] (3) In the heating step, the magnet 3c is heated to a temperature that is at least two times but less than three times the glass transition temperature. By doing so, when the magnet 3c is inserted into the through-hole 3b, the thermosetting resin 15 can be reliably and rapidly hardened.

[0040] (4) In parallel with the heating step, a pressing step is performed in which the core 3 a is pressed in the axial direction, and after the pressing step is completed, the through holes 3 b are filled with the thermosetting resin 15. This makes it possible to prevent the thermosetting resin 15 from leaking to the outside from the gaps between the multiple steel plates in the core 3 a.

[0041] (5) The core 3a has a shaft hole 2a through which the shaft 2 can pass in the axial direction, and in the pressing step, the peripheral edge 14 of the shaft hole 2a is pressed. In this way, it is possible to fill gaps between the multiple steel plates in the core 3a.

[0042] (6) In the insertion step, a plurality of magnets 3c are simultaneously inserted into the through-holes 3b, thereby shortening the time required for the thermosetting resin 15 to harden.

[0043] (7) A magnet heating holder 6 is provided to hold the magnet 3c, and in the heating step, the magnet heating holder 6 is heated. In the insertion step, the heated magnet 3c is dropped from the magnet heating holder 6 onto the core 3a, thereby inserting the magnet 3c into the through-hole 3b. In this way, the heated magnet 3c can be inserted directly into the through-hole 3b without any intervention, thereby suppressing temperature changes.

[0044] (8) In the insertion step, the magnet 3c is pushed out from the magnet heating holder 6 and inserted into the through-hole 3b. In this way, the magnet 3c can be inserted into the through-hole 3b.

[0045] (9) A manufacturing device for manufacturing a rotor 3 of a rotating electric machine 100 including a core 3a made of laminated steel plates and magnets 3c inserted into through holes 3b of the core 3a, the manufacturing device including an annular magnet heating holder 6 for holding the magnets 3c to be heated, and a center shaft 7 arranged coaxially with the magnet heating holder 6 and pressing the core 3a in the axial direction. This makes it possible to provide a rotor 3 of a rotating electric machine 100 with reduced cost and improved reliability.

[0046] (10) The center shaft 7 is disposed radially inward in the magnet heating holder 6. This allows the center axes of the magnet heating holder 6 and the core pressing jig to be aligned.

[0047] (11) The rotating electric machine 100 includes a core 3a made of laminated steel plates, a magnet 3c inserted into a through hole 3b of the core 3a, an annular magnet heating holder 6 that holds the heated magnet 3c, and a center shaft 7 that is arranged coaxially with the magnet heating holder 6 and presses the core 3a in the axial direction. This configuration makes it possible to provide a rotating electric machine 100 that is cost-reduced and has improved reliability.

[0048] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted.

[0049] REFERENCE SIGNS LIST 1 Housing 2 Shaft 2a Shaft hole 3 Rotor 3a Core 3b Through hole 3c Magnet 4 Stator 5 Bearing 6 Magnet heating holder 6a Center hole 6b Magnet hole 6c Fitting portion 7 Center shaft 8 Magnet insertion guide 8a First through hole 8b Second through hole 8c Tapered portion 11 Pressure generating jig 11a Second protrusion 11b Main body 12 Core holder 12a First protrusion 13 Steel plate 14 Peripheral edge 15 Thermosetting resin 15a Viscosity reduction area 15b Hardening area 100 Rotating electric machine

Claims

1. A method for manufacturing a rotor for a rotating electric machine that includes a core made of laminated steel plates and magnets that are inserted into through holes in the core, the method comprising: a heating step for heating the magnets; and an insertion step for inserting the heated magnets into the through holes filled with thermosetting resin.

2. A method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein in the heating step, the magnets are heated to at least the glass transition temperature at which the thermosetting resin hardens.

3. A method for manufacturing a rotor for a rotating electric machine according to claim 2, wherein in the heating step, the magnet is heated to a temperature that is at least two times but less than three times the glass transition temperature.

4. A method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein a pressing step of pressing the core in the axial direction is carried out in parallel with the heating step, and after the pressing step is completed, the through holes are filled with the thermosetting resin.

5. A method for manufacturing a rotor for a rotating electric machine according to claim 4, wherein the core has a shaft hole through which a shaft can pass in the axial direction, and in the pressing step, the peripheral edge of the shaft hole is pressed.

6. A method for manufacturing a rotor for a rotating electric machine according to claim 1, wherein in the inserting step, a plurality of the magnets are simultaneously inserted into the through holes.

7. A method for manufacturing a rotor for a rotating electric machine according to claim 1, comprising: a magnet heating holder for holding the magnet; in the heating step, the magnet heating holder is heated; and in the insertion step, the heated magnet is dropped from the magnet heating holder onto the core, thereby inserting the magnet into the through hole.

8. A method for manufacturing a rotor for a rotating electric machine according to claim 7, wherein in the inserting step, the magnet is pushed out from the magnet heating holder and inserted into the through hole.

9. A manufacturing device for manufacturing a rotor for a rotating electric machine, the rotor comprising a core made of laminated steel plates and a magnet inserted into a through-hole of the core, the manufacturing device comprising: an annular magnet heating holder for holding the magnet to be heated; and a center shaft arranged coaxially with the magnet heating holder for pressing the core in the axial direction.

10. A manufacturing device according to claim 9, wherein the center shaft is disposed radially inward in the magnet heating holder.

11. A rotating electric machine comprising a core made of laminated steel plates and a magnet inserted into a through hole of the core, the rotating electric machine also comprising: an annular magnet heating holder that holds the heated magnet; and a center shaft that is arranged coaxially with the magnet heating holder and presses the core in the axial direction.

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