TW202023148A - Method for producing stator for rotating electrical machine, and rotating electrical machine - Google Patents

Abstract

Provided are: a method for producing a rotating electrical machine stator which makes it possible to increase the efficiency of a rotating electrical machine and easily smooth out the inner-circumferential surface of a magnetic wedge so as to form the same cylindrical lateral surface as does the inner-circumferential surface of the stator core. A method for producing a stator 3 of a rotating electrical machine, the method having: a first step for filling an opening 11 of a slot 8 of a stator core 7 with a mixture 17 which contains a magnetic powder 15 and an uncured or partially cured resin 16; a second step for smoothing out the inner-circumferential surface of the mixture 17 so as to form the same cylindrical lateral surface as does the inner-circumferential surface of the stator core 7 by using a flexible sheet 18 positioned along the inner-circumferential surface of the stator core 7; and a third step for forming a magnetic wedge 14 by curing the resin 16 while the inner-circumferential surface of the mixture 17 is in a smoothed state.

Description

Method for manufacturing stator of rotating electric machine and rotating electric machine

The present invention relates to a method for manufacturing a stator of a rotating electric machine and the rotating electric machine.

The rotating electric machine has a rotating shaft, a rotor fixed on the outer peripheral side of the rotating shaft, and a stator arranged on the outer peripheral side of the rotor at intervals. The stator includes a stator core and coils inserted into a plurality of slots formed on the inner peripheral side of the stator core. Roughly classified, each slot has a storage portion for accommodating a coil, and an opening that opens on the inner peripheral surface of the stator core. Previously, it is known that a magnetic wedge containing a mixture of magnetic powder and resin is provided at the opening of each groove. Thereby, since the high-frequency magnetic flux flows along the inner circumferential surface of the stator core and the inner circumferential surface of the magnetic wedge, the leakage of the high-frequency magnetic flux from the stator side to the rotor side is suppressed. Therefore, the efficiency of the rotating electric machine can be improved.

Patent Document 1 discloses a method of manufacturing the stator of the above-mentioned rotating electric machine. In this manufacturing method, an injection cylinder with an outer diameter slightly smaller than the inner diameter of the stator core is used to fill the openings of the plurality of slots with a mixture containing magnetic powder and semi-hardened resin. After that, the resin is hardened to shape the magnetic wedge.

[Prior Technical Literature] [Patent Literature] [Patent Document 1] Japanese Patent Laid-Open No. 61-026453

[Problems to be solved by the invention] However, the above-mentioned prior art has the following problems. In the method of manufacturing a stator for a rotating electric machine in Patent Document 1, because there is a difference between the inner diameter of the stator core and the outer diameter of the injection cylinder, the inner peripheral surface of the magnetic wedge cannot be compared to the inner peripheral surface of the stator core. Same circumference. Therefore, the leakage of high-frequency magnetic flux from the stator side to the rotor side cannot be sufficiently suppressed. In addition, the outer diameter of the injection cylinder must be changed according to the inner diameter of the stator core.

In view of the above-mentioned situation, the present invention makes it easy to make the inner circumferential surface of the magnetic wedge and the inner circumferential surface of the stator core equal to the same cylindrical side surface, and improve the efficiency of the rotating electric machine as one of the problems.

[Technical means to solve the problem] In order to solve the above-mentioned problems, the composition described in the scope of patent application is applied. The present invention includes a plurality of methods to solve the above-mentioned problems, but as an example, the present invention is to manufacture coils including a stator core, inserted into a plurality of slots formed on the inner peripheral side of the stator core, and respectively formed in the above A method for the stator of a rotating electric machine with the openings of the plurality of slots on the inner peripheral surface of the stator core and containing a plurality of magnetic wedges containing a mixture of magnetic powder and resin, and has: the first process, which will contain the above magnetic powder And the above-mentioned mixture of the above-mentioned resin in the uncured state or the semi-hardened state is filled into the openings of the plurality of grooves; the second process uses a flexible sheet arranged along the inner peripheral surface of the stator core to fill The inner peripheral surface of the mixture of the above-mentioned magnetic powder and the above-mentioned resin in the unhardened or semi-hardened state to the opening of the plurality of slots becomes even with respect to the inner peripheral surface of the stator core to become the same cylindrical side surface; And the third process is to harden the resin in a state where the inner peripheral surface of the mixture becomes even, and to shape the magnetic wedge.

[Effect of invention] According to the present invention, the inner circumferential surface of the magnetic wedge can be easily made uniform with respect to the inner circumferential surface of the stator core in such a way that the inner circumferential surface of the stator core becomes the same cylindrical side surface, thereby improving the efficiency of the rotating electric machine.

In addition, issues, constitutions, and effects other than the above are clarified by the following description.

With reference to the drawings, an embodiment of the present invention will be described.

Fig. 1 is a radial sectional view showing the structure of the rotating electric machine in this embodiment. Fig. 2 is a partial enlarged cross-sectional view showing the structure of the stator of the rotating electric machine in this embodiment.

The rotating electric machine of this embodiment is a squirrel-cage induction motor, and includes a rotating shaft 1, a rotor 2 fixed to the outer peripheral side of the rotating shaft 1, and a stator 3 arranged on the outer peripheral side of the rotor 2 at intervals.

The rotor 2 is provided with: a rotor core 4; a plurality of guide bars 6, which are respectively inserted into a plurality of slots 5 formed on the outer peripheral side of the rotor core 4, and in the axial direction of the rotor core 4 (in FIG. 1 perpendicular to the paper surface) Direction) extending; an end ring (not shown), which is arranged on the axial side of the rotor core 4, connecting one side end of the plurality of guide bars 6; and an end ring (not shown), which is arranged on the rotor core The other side of the axial direction of 4 is connected to the other side ends of a plurality of guide bars 6. The rotor core 4 includes a plurality of electromagnetic steel sheets laminated in the axial direction.

The stator 3 includes a stator core 7 and a coil 9 inserted into a plurality of slots 8 formed on the inner peripheral side of the stator core 7. The stator core 7 includes a plurality of electromagnetic steel sheets laminated in the axial direction. The coil 9 has a portion inserted into the slot 8 and a portion protruding from the slot 8 to one side and the other side of the stator core 7 in the axial direction (refer to FIG. 15 below). Then, when power is supplied to the coil 9, the stator 3 generates a rotating magnetic field, and the rotor 2 and the rotating shaft 1 are rotated.

Each slot 8 roughly includes a storage portion 10 that accommodates the coil 9 and an opening portion 11 that opens on the inner peripheral surface of the stator core 7. Each slot 8 is a half-open type, and is formed such that the width dimension of the opening 11 in the circumferential direction (the left-right direction in FIG. 2) of the stator core 7 is smaller than the width dimension of the storage portion 10. An insulating material 12A (slot liner) is provided on the inner wall of the storage portion 10 of each slot 8, and the insulating material 12A and the insulating material 12B (insert strip) cover the coil 9 together.

Between a plurality of slots 8 of the stator core 7, a plurality of teeth 13 are formed. If the following magnetic wedge 14 is not provided in the opening 11 of each slot 8, the magnetic flux density will be uneven due to the difference between the air in the opening 11 of the slot 8 and the magnetic permeability of the tooth 13 . Therefore, high-frequency magnetic flux leaks from the stator 3 side to the rotor 2 side, causing loss. Therefore, in order to suppress such loss and improve the efficiency of the rotating electric machine, a magnetic wedge 14 is provided in the opening 11 of each slot 8. The magnetic wedge 14 contains a mixture 17 including a magnetic powder 15 (for example, iron powder in detail) and a resin 16, and the volume ratio of the magnetic powder 15 reaches, for example, 60%.

Furthermore, in this embodiment, the magnetic wedges 14 are provided in a part of the opening 11 and the storage 10 of each slot 8. In other words, the magnetic wedge 14 has a shape that is in contact with the inner wall of the opening portion 11, the inner wall of the storage portion 10, and the insulating materials 12A and 12B. Thereby, even if the magnetic attraction force of the rotor 2 works, the magnetic wedge 14 will not fall off from the slot 8 of the stator core 7.

Next, the manufacturing method of the stator of the rotating electric machine of this embodiment is demonstrated. FIG. 3 is a flowchart showing the manufacturing process of the method for manufacturing the stator of the rotating electric machine in this embodiment.

In step S1, the insulating material 12A, the coil 9, and the insulating material 12B are inserted in the slots 8 of the stator core 7 in this order, and they are fixed with varnish or the like (refer to FIG. 4).

Thereafter, in step S2, a flexible and water-resistant resin sheet 18 is arranged along the entire inner peripheral surface of the stator core 7 (refer to FIG. 5). The sheet 18 has a quadrangular shape and is wound into a cylindrical state (for example, as shown in FIG. 6, the two opposing sides are in contact with each other, and the first corner is in contact with the second corner, and the third corner The state of being wound in contact with the fourth corner).

Thereafter, in step S3, the mixture 17 containing the magnetic powder 15 and the resin 16 in the uncured or semi-cured state is filled from the axial side of the stator core 7 to a portion of the opening 11 and the storage portion 10 of each slot 8. At this time, if the mixture 17 overflows from each slot 8 to the other axial side of the stator core 7, the overflowed mixture 17 is removed.

Thereafter, in step S4, the sheet 18 is used (in detail, the sheet 18 is urged along the inner peripheral surface of the stator core 7) to make the inner peripheral surface of the mixture 17 filled in each slot 8 face the stator The inner peripheral surface of the core 7 becomes uniform so as to become the same cylindrical side surface (refer to FIG. 7). At this time, if the mixture 17 overflows from each slot 8 to one side or the other side in the axial direction of the stator core 7, the overflowed mixture 17 is removed.

Thereafter, in step S5, the resin 16 is cured by heating, and the magnetic wedge 14 is formed. Furthermore, if the sheet 18 does not have heat resistance, the sheet 18 is removed before the resin 16 hardens. On the other hand, if the sheet 18 has heat resistance, the sheet 18 may be removed after the resin 16 is cured.

As described above, in the present embodiment, the inner peripheral surface of the magnetic wedge 14 can be made uniform with respect to the inner peripheral surface of the stator core 7 to be the same cylindrical side surface. Thereby, the leakage of high-frequency magnetic flux from the stator 3 side to the rotor 2 side can be suppressed, and the efficiency of the rotating electric machine can be improved. In addition, by using the flexible sheet 18, the inner peripheral surface of the magnetic wedge 14 can be easily made even. In addition, even if the inner diameter size of the stator core 7 changes, it can be easily handled.

Furthermore, in the above-mentioned embodiment, the case where the resin 16 is a heat-curing type is described as an example, but it is not limited to this, and changes can be made without departing from the spirit and technical idea of the present invention. For example, the resin 16 may be a hot-melt type (that is, one that is hardened by cooling).

In addition, in the above-mentioned embodiment, the case where the magnetic wedge 14 is provided in the opening 11 of the slot 8 and a part of the storage portion 10 has been described as an example, but it is not limited to this. The magnetic wedge 14 can also be provided only in the slot 8.的 Opening 11. In addition, in the above-mentioned one embodiment, the case where each groove 8 is a half-open type and the width dimension of the opening 11 is smaller than the width dimension of the storage part 10 has been described as an example, but it is not limited to this, and may be Each groove 8 is an open type, and the width of the opening 11 is formed in the same manner as the width of the storage portion 10.

Also, in the above-mentioned embodiment, although not specifically explained, before filling the mixture 17 into the opening 11 of each slot 8, the inner circumferential surface of the stator core 7 (in other words, the inner circumferential surface of the tooth 13 ) Coating release agent. Thereafter, an adhesive may be used to attach the resin sheet 18 to the inner peripheral surface of the stator core 7. In this case, by removing the sheet 18, the mixture adhering to the inner circumferential surface of the stator core 7 can be easily removed.

In addition, in the above-mentioned embodiment, the case where the inner peripheral surface of the mixture 17 filled in the openings 11 of the plurality of grooves 8 is made uniform using the resin sheet 18 has been described as an example, but it is not limited to Therefore, changes can be made within the scope not departing from the purpose and technical idea of the present invention. For example, as described in the first modified example shown in FIG. 8, a flexible magnetic sheet 18A can be used to make the inner peripheral surface of the mixture 17 filled in the openings 11 of the plurality of grooves 8 equal. In this modification, even if no adhesive is used, the magnetic sheet 18A can be attached to the inner peripheral surface of the stator core 7. In addition, the magnetic powder 15 may be attracted to the inner peripheral surface side of the mixture 17 by the magnetic force of the magnetic sheet 18A. Furthermore, in a state where the inner peripheral surface of the mixture 17 becomes even and the magnetic powder 15 is attracted to the inner peripheral surface of the mixture 17, the resin 16 can be hardened to form the magnetic wedge 14. Thereby, the unevenness of the magnetic permeability in the inner peripheral surface of the magnetic wedge 14 can be suppressed. Therefore, leakage of high-frequency magnetic flux from the stator 3 side to the rotor 2 side can be further suppressed, thereby further improving the efficiency of the rotating electric machine. Furthermore, it is also possible to use the resin sheet 18 in the same manner as in the above-mentioned embodiment, but in order to achieve the same purpose as the first modification described above, an electromagnet or the like may be arranged inside the sheet 18.

In addition, in the above-mentioned embodiment, the case where the sheet 18 is arranged along the entire inner peripheral surface of the stator core 7 has been described as an example, but it is not limited to this, and is within the scope of not departing from the spirit and technical idea of the present invention. Can be changed. The sheet 18 or 18A may be arranged so as to cover at least one groove 8, that is, at least along the inner peripheral surface of the two tooth portions 13. Specifically, for example, as shown in the second modification example shown in FIG. 9, the two grooves 8 may be covered, that is, along the inner peripheral surface of the three teeth 13, the sheet 18 or 18A. Furthermore, for example, as described in the third modification shown in FIG. 10, the sheet 18 or 18A may be arranged along a quarter of the inner peripheral surface of the stator core 7. Furthermore, for example, as described in the fourth modification shown in FIG. 11, the sheet 18 or 18A may be arranged along one half of the inner peripheral surface of the stator core 7. In addition, for example, as described in the fifth modification shown in FIG. 12, the sheet 18 or 18A may be arranged along three-quarters of the inner peripheral surface of the stator core 7. Furthermore, while moving the sheet 18 or 18A, the inner peripheral surface of the mixture 17 filled in the opening 11 of each groove 8 may be made even. In these modified examples, even if the inner diameter size of the stator core 7 changes, it can be easily dealt with.

In addition, in the above-mentioned embodiment, as a method of winding the quadrilateral sheet 18, two opposing sides are in contact with each other, the first corner is in contact with the second corner, and the third corner is in contact with the fourth corner. The case of winding is described as an example, but it is not limited to this, and changes can be made without departing from the spirit and technical idea of the present invention. For example, as described in the sixth modification shown in FIG. 13, although the two opposite sides are in contact, the first corner and the second corner are not in contact, and the third corner and the fourth corner are not in contact, Wind the sheet 18 or 18A diagonally. Thereby, even if the inner diameter size of the stator core 7 changes, it can be easily dealt with.

Furthermore, in the above-mentioned embodiment, after arranging the sheet 18 along the inner peripheral surface of the stator core 7, each slot 8 is filled with the mixture 17 from the axial side of the stator core 7 to overflow each slot 8 to the stator core The case where the mixture 17 on the other side of the axis of 7 is removed is described as an example, but it is not limited to this, and can be changed without departing from the spirit and technical idea of the present invention. Using FIG. 14 and FIG. 15, such a variation example will be explained.

FIG. 14 is a flow chart showing the manufacturing process of the method of manufacturing the stator of the rotating electric machine in this modification.

In step S1, the insulating material 12A, the coil 9, and the insulating material 12B are inserted into the slots 8 of the stator core 7 in this order, and these are fixed with varnish or the like. Thereafter, in step S6, for example, cylindrical jigs 19 are arranged on one side and the other side of the stator core 7 in the axial direction, and the grooves 8 are covered with the jigs 19 (refer to FIG. 15).

After that, in step S3, the mixture 17 containing the magnetic powder 15 and the resin 16 in the uncured state or the semi-cured state is filled into the slots 8 from the inner peripheral side of the stator core 7. At this time, if the mixture 17 overflows from each slot 8 to the inner peripheral side of the stator core 7, the overflowed mixture 17 is removed.

After that, in step S2, the sheet 18 or 18A is arranged along the inner peripheral surface of the stator core 7. After that, in step S4, using the sheet 18 or 18A, the inner peripheral surface of the mixture 17 filled in the respective grooves 8 is made uniform with respect to the inner peripheral surface of the stator core 7 to be the same cylindrical side surface. Thereafter, the resin 16 is hardened by heating, and the magnetic wedge 14 is formed.

Even in this modified example, the inner circumferential surface of the magnetic wedge 14 can be made uniform with respect to the inner circumferential surface of the stator core 7 so as to be the same cylindrical side surface. Thereby, the leakage of high-frequency magnetic flux from the stator 3 side to the rotor 2 side can be suppressed, thereby improving the efficiency of the rotating electric machine. Furthermore, by using the flexible sheet 18 or 18A, the inner peripheral surface of the magnetic wedge 14 can be easily made even. In addition, even if the inner diameter size of the stator core 7 changes, it can be easily handled.

Furthermore, in the above, the rotating electric machine to which the present invention is applied has been described with a squirrel-cage induction motor (specifically, a rotor 2 having a guide bar 6 and an end ring) as an example, but not Limited to this. That is, the present invention can also be applied to, for example, a permanent magnet synchronous motor (specifically, a rotor with permanent magnets) or a generator.

1: Rotation axis 2: Rotor 3: stator 4: rotor core 5: Multiple slots 6: Multiple guide bars 7: Stator core 8: Slot 9: Coil 10: Storage Department 11: Opening 12A: Insulating material (groove lining) 12B: Insulation material (insert strip) 13: Teeth 14: Magnetic wedge 15: Magnetic powder 16: resin 17: mixture 18: flakes 18A: magnetic sheet 19: Fixture

Fig. 1 is a radial sectional view showing the structure of a rotating electric machine in one embodiment of the present invention. Fig. 2 is a partial enlarged cross-sectional view showing the structure of the stator of the rotating electric machine in one embodiment of the present invention. Fig. 3 is a flow chart showing the manufacturing process of the stator manufacturing method of the rotating electric machine in one embodiment of the present invention. 4 is a cross-sectional view showing a state in which insulating materials and coils are inserted into the slots of the stator core in one embodiment of the present invention. 5 is a cross-sectional view in the radial direction of sheets arranged along the inner circumferential surface of the stator core in one embodiment of the present invention. Fig. 6 is a perspective view showing a method of winding a sheet in one embodiment of the present invention. Fig. 7 is a cross-sectional view showing a state in which the inner peripheral surface of the mixture filled in the slots of the stator core is made even by using the sheet in one embodiment of the present invention. 8 is a cross-sectional view showing a state in which the inner peripheral surface of the mixture filled in the slots of the stator core is averaged using the sheet in the first modification of the present invention, and the magnetic powder is attracted to the inner peripheral surface of the mixture. Fig. 9 is a cross-sectional view in the radial direction of sheets arranged along the inner circumferential surface of the stator core in the second modification of the present invention. Fig. 10 is a cross-sectional view in the radial direction of sheets arranged along the inner circumferential surface of the stator core in the third modification of the present invention. FIG. 11 is a cross-sectional view in the radial direction of sheets arranged along the inner peripheral surface of the stator core in the fourth modification of the present invention. Fig. 12 is a cross-sectional view in the radial direction of sheets arranged along the inner peripheral surface of the stator core in the fifth modification of the present invention. Fig. 13 is a perspective view showing a method of winding a sheet in a sixth modification of the present invention. 14 is a flowchart showing the manufacturing process of the method of manufacturing the stator of the rotating electric machine in the seventh modification of the present invention. 15 is a side view showing the jigs arranged on one side and the other side of the stator core in the axial direction in the seventh modification of the present invention.

8: Slot

9: Coil

10: Storage Department

11: Opening

12A: Insulating material (groove lining)

12B: Insulation material (insert strip)

13: Teeth

14: Magnetic wedge

15: Magnetic powder

16: resin

17: mixture

18: flakes

Claims (6)

A method for manufacturing a stator of a rotating electric machine, which manufactures a stator core, a coil inserted into a plurality of slots formed on the inner peripheral side of the stator core, and the plurality of openings respectively formed on the inner peripheral surface of the stator core The opening of a slot and containing a plurality of magnetic wedges containing a mixture of magnetic powder and resin is characterized by having: The first process includes filling the above-mentioned mixture containing the above-mentioned magnetic powder and the above-mentioned resin in an unhardened or semi-hardened state into the openings of the plurality of grooves; The second process uses a flexible sheet arranged along the inner peripheral surface of the stator core to fill the openings of the plurality of slots and include the magnetic powder and the resin in the uncured or semi-cured state. The inner circumferential surface of the mixture becomes even with respect to the inner circumferential surface of the stator core in such a way that it becomes the same cylindrical side surface; and The third process is to harden the resin in a state where the inner peripheral surface of the mixture becomes even, and to shape the magnetic wedge. Such as the manufacturing method of the stator of the rotating electric machine of claim 1, wherein The second process is to use a flexible magnetic sheet arranged along the inner peripheral surface of the stator core to fill the openings of the plurality of slots and include the magnetic powder and the resin in the uncured or semi-cured state. The inner peripheral surface of the mixture becomes equal to the inner peripheral surface of the stator core so as to become the same cylindrical side surface, and the magnetic powder is attracted to the inner peripheral surface side of the mixture, The third process is to harden the resin to form the magnetic wedge in a state where the inner peripheral surface of the mixture is made uniform and the magnetic powder is attracted to the inner peripheral surface side of the mixture. Such as the manufacturing method of the stator of the rotating electric machine of claim 1, wherein The sheet is arranged along the whole or part of the inner peripheral surface of the stator core. Such as the manufacturing method of the stator of the rotating electric machine of claim 1, wherein The sheet is attached to the inner peripheral surface of the stator core using an adhesive. A rotating electric machine including a rotating shaft, a rotor fixed on the outer peripheral side of the rotating shaft, and a stator arranged on the outer peripheral side of the rotor at intervals, and The stator includes a stator core, coils inserted into a plurality of slots formed on the inner peripheral side of the stator core, and openings of the plurality of slots respectively provided on the inner peripheral surface of the stator core, and containing magnetic powder The plural magnetic wedges of the mixture of resin and resin are characterized by: The magnetic wedge uses a flexible sheet arranged along the inner peripheral surface of the stator core to fill the openings of the plurality of slots and include the magnetic powder and the resin in the uncured or semi-cured state. In a state where the inner peripheral surface of the mixture becomes uniform with respect to the inner peripheral surface of the stator core so as to become the same cylindrical side surface, the resin is cured and molded. Such as the rotating electrical machine of claim 5, where The magnetic wedges are made using flexible magnetic sheets arranged along the inner peripheral surface of the stator core to fill the openings of the plurality of slots and include the magnetic powder and the resin in the uncured or semi-cured state The inner peripheral surface of the mixture becomes uniform with respect to the inner peripheral surface of the stator core so as to become the same cylindrical side surface, and the magnetic powder is attracted to the inner peripheral surface side of the mixture, and the resin is cured and molded.

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