JP2015192590A - rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor capable of suppressing demagnetization generated when fixing a magnet in a magnet hole, thereby eliminating leakage magnetic flux.SOLUTION: A rotor 10a includes a rotor core 12, fastening members 14, magnets 16, end plates 18, and a rotary shaft 20. On one face m and the other face n of the magnet 16, both ends of the faces are projection portions 30. On the one face m and the other face n, the projection portions 30 are flush with the other portions. On both ends, recesses 32 are formed between the one face m and the other face n. The projection portions 30 are formed on both ends of the planar magnet 16, and when the magnet 16 is observed from an axial direction of the rotor core 12, both the ends of the magnet 16 are formed as recessed shapes directing the center of the magnet 16.

Description

  The present invention relates to a rotor used in a rotating electrical machine.

  Conventionally, various rotating electrical machines 104 having an annular stator 102 around a cylindrical rotor 100 have been developed. When the rotating electrical machine 104 is applied to the compressor 106 as shown in FIG. 7, the stator 102 is disposed in the cylindrical pipe 108, and the rotor 100 is disposed therein. The compressor 106 is provided with a pipe 110 that supplies a refrigerant, a pipe 112 that discharges the refrigerant, a terminal 114 connected to a winding, and a compression mechanism 116. When the rotor 100 rotates, the refrigerant is sucked into the compression mechanism 116, compressed, and discharged.

  The rotor 100 includes a rotor core 120 in which the disk-shaped core sheets 118 shown in FIG. 8 are stacked, a magnet 124 embedded in a magnet hole 122 formed in the rotor core 120, and an end plate 126 disposed at an end of the rotor core 120. , And a rotating shaft 128 attached to the center of the rotor core. A bridge portion 130 is formed from the end of the magnet hole 122 to the outer periphery of the rotor core 120. In the following Patent Document 1, a magnet 122 is welded using a pulse laser and fixed to the rotor core 120.

  However, since Patent Document 1 uses laser welding, the temperature during welding rises to about 1500 ° C. There is a possibility that the magnet 124 is demagnetized due to the temperature rise and the rotational performance is lowered.

  In addition, leakage magnetic flux is generated in the bridge portion 130. Since the leakage magnetic flux does not contribute to the rotation of the rotor 100, it is necessary to eliminate the leakage magnetic flux. The following Patent Document 1 does not disclose countermeasures against leakage magnetic flux.

JP 2000-83334 A

  An object of this invention is to provide the rotor which suppresses the demagnetization generate | occur | produced when fixing a magnet in a magnet hole, and eliminates a leakage magnetic flux.

  The rotor of the present invention includes a rotor core in which core sheets made of electromagnetic steel sheets are laminated, a fastening hole provided in the rotor core, a fastening member that is inserted into the fastening hole and fixes the core sheets, and the rotor core. A formed magnet hole, a cutting part that forms a space from the end of the magnet hole to the outer periphery of the rotor core, a magnet having one surface and the other surface, embedded in the magnet hole, and having a changed width; And an adhesive for fixing a magnet to the rotor core.

  One surface of the magnet is disposed on the outer peripheral side of the rotor core, the other surface of the magnet is disposed on the center side of the rotor core, the width of the one surface of the magnet is Wo, the width of the center of the magnet is Wc, When the width is Wi, Wi ≧ Wo> Wc.

  The fastening hole is provided on the inner side of the magnet hole in the core sheet, and the caulking is provided on the outer side of the magnet hole in the core sheet.

  In the present invention, the leakage magnetic flux can be eliminated by forming a cut portion that is a space from the end of the magnet hole to the outer periphery of the rotor core instead of the conventional bridge portion. Further, by adhering the magnet with an adhesive, it is possible to prevent demagnetization when fixing the magnet in the magnet hole, and to integrate the magnet and the rotor core.

It is a figure which shows the rotor of this invention, (a) is a top view, (b) is the sectional view on the AA line of (a). It is a figure which shows the various shapes of a protrusion part. (A) is a top view of the punched core sheet, and (b) is a diagram in which magnets are embedded in the rotor core. It is a figure which defines the shape of a magnet, (a) is a top view, (b) is an enlarged view in the dotted line of (a). It is the figure which provided the crimp to the outer side rotor core. It is a figure which shows the rotor of an arc-shaped magnet hole. It is a figure which shows a compressor. It is a figure which shows the cross section of the conventional rotor.

  The rotor of the present invention will be described with reference to the drawings. The rotor is used for a rotating electric machine. The rotating electrical machine can be applied to a compressor or the like, as in the past. In the description of a plurality of embodiments, the same content as that described in one embodiment may be omitted in other embodiments.

  The rotor 10a of the present invention shown in FIG. 1 includes a rotor core 12, a fastening member 14, a magnet 16, an end plate 18, and a rotating shaft 20. The rotor core 12 has a magnet hole 22, a cutting portion 24, and a fastening hole 26 a, the fastening member 14 is inserted into the fastening hole 26 a, and the magnet 16 is embedded in the magnet hole 22.

  The rotor core 12 is a laminate of core sheets 28. The core sheet 28 can be formed by punching a magnetic steel sheet made of soft magnetic material. The thickness of the core sheet 28 is, for example, about 0.2 to 1 mm, and preferably about 0.3 to 0.5 mm. The surface of the core sheet 28 covers an insulating film and prevents eddy currents between the core sheets 28. As shown in FIG. 1A, the outer shape of the core sheet 28 is circular except for a cutting portion 24 described later.

  The core sheet 28 has a magnet hole 22 formed therein. As shown in FIG. 1A, in the plane of the core sheet 28, the magnet hole 22 has a band shape and is bent so as to have a U shape or a V shape. Both ends of the magnet hole 22 are disposed near the outer periphery of the core sheet 28. Each magnet hole 22 of the core sheet 28 has the same shape and is symmetrical about the rotation axis 20. When the rotor core 12 is formed, the magnet hole 22 communicates from one end to the other end.

  A cut portion 24 is formed from the end of the magnet hole 22 to the outer periphery of the core sheet 28. The cutting part 24 is a space and is a part without an electromagnetic steel plate. The cutting part 24 has a shape in which the magnet hole 22 is extended to the outer periphery of the core sheet 28.

  The width of the cutting part 24 in FIG. 1 is the same as that of the magnet hole 22, but the width of the cutting part 24 may be different from that of the magnet hole 22. The conventional bridge portion 130 shown in FIG. 8 is replaced with a space, and leakage flux can be prevented. In the rotor core 12, the outer side of the magnet hole 22 and the cutting part 24 is the outer rotor core 12 o, and the inner side is the inner rotor core 12 i. The outer rotor core 12 o and the inner rotor core 12 i are connected via a magnet 16.

  In this embodiment, a fastening hole 26a is provided in the outer rotor core 12o. When the core sheet 28 is laminated, the fastening member 14 is inserted into the fastening hole 26a, and the laminated core sheet 28 is fixed. Examples of the fastening member 14 include rivets, bolts and nuts, and their shafts enter the fastening holes 26a.

  Examples of the magnet 16 include sintered magnets such as ferrite magnets, neodymium magnets, samarium cobalt magnets, and alnico magnets. The magnet 16 has a plate shape, and one surface m and the other surface n of the magnet 16 are in contact with the inner wall of the magnet hole 22. The number of the magnet holes 22 and the magnets 16 is an even number, and the magnets 16 alternately arrange N poles and S poles on the outer periphery of the rotor core.

  As shown in FIG. 2A, when the rotor core 12 is viewed in plan on the one surface m and the other surface n of the magnet 16, both ends thereof are convex portions 30. On one surface m and the other surface n, the convex portion 30 is flush with the other portions. At both ends of the magnet 16, a recess 32 is formed between the one surface m and the other surface n. The plate-shaped magnet 16 has a shape in which convex portions 30 are provided at both ends. When the magnet 16 is viewed from the axial direction of the rotor core 12, both ends of the magnet 16 become concave toward the center of the magnet 16. Yes.

  If the width of the magnet 16 changes from one surface m to the other surface n of the magnet 16 and the convex portions 30 are formed at both ends of the one surface m and the other surface n, the shape of the convex portion 30 is not limited, As shown in FIG. 2, shapes such as an arc, a quadrangle, and a triangle are listed. Moreover, you may combine the convex part 30 of a different shape in the one magnet 16. FIG.

  Before embedding the magnet 16 in the magnet hole 22, the adhesive 34 is applied to one surface m and the other surface n of the magnet 16 to form a thin film layer of the adhesive 34. When the adhesive 34 is applied to the one surface m and the other surface n of the magnet 16, the adhesion area can be increased by the convex portion 30 of the magnet 16. By expanding the adhesion area, the adhesion strength between the magnet 16 and the inner wall of the magnet hole 22 is increased.

  The type of the adhesive 34 is not limited as long as the magnet 16 is bonded to the rotor core 12 such as an epoxy resin adhesive, an acrylic resin adhesive, and a urethane resin adhesive. Since it is fixed with the adhesive 34, there is no possibility that the magnet 16 is demagnetized.

  In addition, when applying the rotary electric machine containing the rotor 10a to a compressor, it is preferable that the adhesive agent 34 selects the material which has tolerance with respect to the temperature of a coolant material or a coolant.

  In order to increase the adhesive strength of the magnet 16, it is preferable that at least one surface m and the other surface n of the magnet 16 are roughened. The surface of the magnet is treated by electroplating or vapor deposition so as to obtain a desired surface roughness. The surface roughness Ra of the magnet 16 is preferably about 0.1 μm or more.

  The end plates 18 are made of a nonmagnetic material and are disposed at both ends of the rotor core 12. Non-magnetic material prevents eddy current loss. As with the core sheet 28, a fastening hole 26b is provided so that the fastening member 14 can be passed therethrough. The shaft of the fastening member 14 is passed through the fastening hole 26b simultaneously with the fastening hole 26a of the core sheet 28, and is fixed by the fastening member 14 so that the rotor core 12 and the end plate 18 are integrated. Further, the end plate 18 is provided with a rotation shaft hole 36b through which the rotation shaft 20 passes.

  The rotary shaft 20 is fitted into the rotary shaft hole 36a at the center of the rotor core 12 and fixed. When the rotating electrical machine including the rotor 10a is applied to a compressor, the rotating shaft 20 extends to the compression mechanism and also serves as the rotating shaft of the compressor. A stator is disposed so as to surround the side of the rotor core 12 to become a rotating electrical machine. The stator includes a coil, and the rotor 10a is rotated by a magnetic field generated by applying a current to the coil.

  Next, a method for manufacturing the rotor 10a will be described. (1) An electromagnetic steel sheet is prepared, punched into a predetermined shape, and the core sheet 28 is formed. As shown in FIG. 3A, when punching is performed, the core sheet 28 is provided with a magnet hole 22, a fastening hole 26a, and a rotary shaft hole 36a. When the outer shape of the core sheet 28 is formed, the magnet hole 22 and the like are formed in the same process or another process. At this point, the cutting portion 24 is not formed, and the bridge portion 38 is formed.

  (2) The rotor core 12 is formed by laminating the core sheets 28. When the core sheet 28 is laminated, the magnet hole 22 and the fastening hole 26a penetrating the rotor core 12 are formed so that the positions of the magnet hole 22 and the fastening hole 26a coincide with each other.

  (3) The rotary shaft 20 is inserted into the rotary shaft hole 36a of the rotor core 12 and fixed. Examples of the fixing method include shrink fitting, cold fitting, press fitting, and welding. At that time, the fastening member 14 may be inserted into the fastening hole 26 a of the core sheet 28, the core sheets 28 may be fixed to each other, and the fastening member 14 may be temporarily removed after the rotary shaft 20 is fixed.

  (4) The magnet 16 is embedded in the magnet hole 22 as shown in FIG. When the magnet 16 is embedded, an adhesive 34 is applied to the magnet 16, and the magnet 16 is fixed to the inner wall of the magnet hole 22 with the adhesive 34. When embedding the magnet 16, the end plate 18 may be disposed at one end of the rotor core 12. At the stage of inserting the magnet 16 into the magnet hole 22, the magnet 16 is prevented from falling out of the magnet hole 22.

  (5) The bridge portion 38 is cut to form the cutting portion 24 that is a space. When cutting the bridge portion 38, it is preferable to fix the core sheet 28 with the fastening member 14. The end plates 18 may be fixed to both ends of the rotor core 12 together with the core sheet 28. Even after cutting the bridge portion 38, the outer rotor core 12 o and the magnet 16 and the inner rotor core 12 i and the magnet 16 are fixed by the adhesive 34. Any cutting device such as a cutter or a saw can be used as long as it can perform the cutting.

  Cutting from the outer periphery of the rotor core 12 toward the end of the magnet hole 22. If a space is provided from the end of the magnet hole 22 to the magnet 12, the cutting device does not reach the magnet 16 at the time of cutting, and the magnet 16 can be protected.

  Since the bridge portion 38 is cut after the magnet 16 is embedded, it is not necessary to align the outer rotor core 12o with respect to the inner rotor core 12i. Even if alignment is not performed, each rotor core 12 is arranged at a desired position.

  In addition, the rotor 10a is arrange | positioned inside a cyclic | annular starter, and a rotary electric machine is comprised. A current is passed through a coil in the stator, and the rotor 10a rotates by a magnetic field generated by the current. When the rotating electrical machine is applied to a compressor, the rotating shaft 20 is connected to the compressor as shown in the prior art. The compressor is driven by the rotation of the rotor 10a.

  Since the bridge portion 34 is cut after the magnet 16 is embedded as described above, there is no need for relative alignment between the inner rotor core 12i and the outer rotor core 12o, and the outer periphery of the rotor core 12 is a perfect circle. The air gap with the stator can be made uniform. Since the air gap is uniform, the rotor 10a is easy to rotate.

  In FIG. 4, in the magnet 16, the outer side of the rotor core 12 is defined as one surface m, and the inner side of the rotor core 12 is defined as the other surface n. When the rotor 10a is viewed from the axial direction of the rotary shaft 20, the width of one surface m of the magnet 12 is Wo, and the width of the other surface n is Wi. Further, the width of the magnet 16 at the center between the one surface m and the other surface n of the magnet 16 is Wc. In this case, Wi ≧ Wo> Wc. This is because in the radial direction of the rotor 10a, if one surface m of the magnet 16 increases, the centrifugal force increases, and the adhesion between the magnet 16 and the rotor core 12 may be released. If it is the structure of a present Example, the one surface m will not become larger than the other surface n, and a centrifugal force will not become large.

  When the fastening hole 26a is provided in the inner rotor core 12i as in the rotor 10b of FIG. 5, the outer rotor core 12o is not integrated with the fastening member 14, and therefore the caulking 40 is provided in the outer rotor core 12o. The core sheets 28 are fixed to each other by the caulking 40 so that the core sheet 28 is difficult to fly by centrifugal force.

  In addition, when the fastening hole 26a is provided in the outer rotor core 12o, the caulking 40 of the outer rotor core 12o is not essential. This is because the core sheet 28 of the outer rotor core 12o is integrated by the fastening member 14.

  The shape of the magnet hole 22 is not limited to a U shape or a V shape. An arcuate magnet hole 22 and a magnet 16 may be used as in the rotor 10c of FIG. Similar to the above embodiment, the magnet 16 is fixed to the rotor core 12 by the cutting portion 24 and the adhesive 34.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the gist thereof. Each embodiment is not an independent or exclusive embodiment, and may be implemented by appropriately combining all or a part of various embodiments.

10a, 10b, 10c: Rotor 12: Rotor core 14: Fastening member 16: Magnet 18: End plate 20: Rotating shaft 22: Magnet hole 24: Cutting part 26a, 26b: Fastening hole 28: Core sheet 30: Convex part 32: Recess 34: Adhesive 36a, 36b: Rotating shaft hole 38: Bridge portion 40: Caulking

Claims (3)

A rotor core in which core sheets made of electromagnetic steel sheets are laminated;
A fastening hole provided in the rotor core;
A fastening member that is inserted into the fastening hole and fixes the core sheets together;
Magnet holes formed in the rotor core;
A cutting part that forms a space from the end of the magnet hole to the outer periphery of the rotor core;
A magnet having one surface and another surface, embedded in the magnet hole, and having a width changed from one surface to the other surface;
An adhesive for fixing a magnet to the rotor core;
With a rotor. One surface of the magnet is disposed on the outer peripheral side of the rotor core, and the other surface of the magnet is disposed on the center side of the rotor core,
2. The rotor according to claim 1, wherein Wi ≧ Wo> Wc, where Wo is the width of one surface of the magnet, Wi is the width of the other surface of the magnet, and Wc is the width of the center between the one surface and the other surface of the magnet. The fastening hole is provided inside the magnet hole in the core sheet,
The rotor according to claim 1 or 2, wherein a caulking is provided outside the magnet hole in the core sheet.

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