Rotary electric machine iron core

Abstract

To provide a rotary electric machine core in which leakage of magnetic flux is reduced even when a permanent magnet is housed inside.SOLUTION: A rotary electric machine core 10 includes a core body 11, a recess 16, a split core member 12, and a support member 13. The plurality of recesses 16 are provided in the circumferential direction of the core body 11, and are cut out in a V-shape in the axial cross section from the outer peripheral wall 17 of the core body 11 toward the radially inner side. The split core member 12 is provided separately from the core body 11, is attached to the recess 16, and forms an accommodation chamber 18 for accommodating the permanent magnet between the split core member 12 and an outer wall of the V-shaped core body 11 forming the recess 16. The support member 13 connects the core body 11 and the split core member 12, and supports the split core member 12 on the core body 11 while securing a distance for forming an accommodation chamber 18 between the core body 11 and the split core member 12.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present embodiment relates to a rotating electrical machine core. [Background technology]

[0002] A rotating electric machine core used as a rotor of a synchronous motor includes an iron core and a permanent magnet attached to the iron core. These rotating electric machine cores are classified into an IPM type in which the permanent magnet is embedded in the iron core, and an SPM type in which the permanent magnet is attached to the outer wall of the iron core. In the case of the IPM type, as shown in FIG. 6, an iron core 100 has an opening 102 in an iron core body 101 for accommodating the permanent magnet. Therefore, the iron core body 101 has a bridge portion 103 at the radially outer end of the opening 102 to maintain the shape of the opening 102.

[0003] However, this bridge portion 103 is provided integrally with the core body 101. Therefore, a portion of the magnetic flux generated by the permanent magnet housed in the opening 102 leaks through this bridge portion 103. As a result, there is a problem in that the leakage of magnetic flux from the permanent magnet leads to a decrease in the efficiency of the rotating electric machine. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-198481 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an object of the present invention is to provide a rotating electric machine core that reduces leakage of magnetic flux even when a permanent magnet is housed inside. [Means for solving the problem]

[0006] The rotating electric machine core of this embodiment includes a core body, recesses, core segments, and a support member. A plurality of recesses are provided in the circumferential direction of the core body, and are V-shaped cutouts in the axial cross section from the outer peripheral wall of the core body radially inward. The core segments are provided separately from the core body and attached to the recesses, forming accommodating chambers for accommodating permanent magnets between them and the V-shaped outer wall of the core body that forms the recesses. The support member connects the core body and the core segments, and supports the core segments to the core body while ensuring a distance between the core body and the core segments to form the accommodating chambers. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic perspective view showing a rotating electric machine core according to an embodiment; [Figure 2] Schematic diagram seen from the direction of arrow II in Figure 1 [Figure 3] Enlarged schematic diagram of the main part of Figure 2 [Figure 4] Enlarged view of part IV in Figure 3 [Figure 5] FIG. 1 is a schematic diagram illustrating steel plates that form a core body in a rotating electrical machine core according to one embodiment. [Figure 6] FIG. 3 is a schematic diagram showing a conventional rotating electric machine core, and corresponds to FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment will be described with reference to the drawings. As shown in Figures 1 and 2, a rotating electric machine core 10 includes a core body 11, split core members 12, and support members 13. The rotating electric machine core 10 is a so-called IPM (Interior Permanent Magnet) type rotating electric machine core that houses permanent magnets 14 inside. The rotating electric machine core 10 has a hole 15 in its radial center through which a shaft member (not shown) passes. In the following description, the direction in which the hole 15 of the rotating electric machine core 10 extends and the direction in which the shaft member (not shown) that passes through the hole 15 extends are referred to as the axial direction. The direction perpendicular to this axial direction is referred to as the radial direction, and the direction of rotation of the rotating electric machine core 10 about the shaft member is referred to as the circumferential direction.

[0009] Both the core body 11 and the core segments 12 are constructed by stacking steel plates (not shown) in the axial direction. The core body 11, which is constructed by stacking steel plates, and the core segments 12 are combined to form a roughly cylindrical rotating electric machine core 10. A hole 15 is provided in the center of the cylindrical rotating electric machine core 10, penetrating it in the axial direction, and a shaft member (not shown) is inserted into this hole 15.

[0010] The rotating electric machine core 10 has a recess 16. The recess 16 is cut out from the outer peripheral wall 17 of the core body 11 radially inward, i.e., toward the center. Specifically, when the rotating electric machine core 10 is viewed from the axial end as shown in FIG. 2 , the recess 16 is cut out in a generally V-shape from the outer peripheral wall 17 of the core body 11 toward the center. A plurality of recesses 16 are provided in the circumferential direction of the core body 11. In the embodiment shown in FIGS. 1 and 2 , six recesses 16 are provided in the circumferential direction of the core body 11. The split core members 12 are attached to the core body 11 at these recesses 16. Therefore, in the embodiment shown in FIGS. 1 and 2 , the rotating electric machine core 10 has six split core members 12.

[0011] The split core members 12 are formed in the shape of sectoral columns corresponding to the shape of the recesses 16. The split core members 12 are formed so that their axial cross-sectional area is smaller than that of the recesses 16. As a result, a predetermined space is secured between the core main body 11 and the split core members 12. This space between the core main body 11 and the split core members 12 is an accommodation chamber 18 that accommodates the permanent magnets 14. The permanent magnets 14 are accommodated in this accommodation chamber 18. The permanent magnets 14 are attached to the core main body 11 by their own magnetic force. The permanent magnets 14 may be fixed more firmly between the core main body 11 and the split core members 12 using, for example, an adhesive.

[0012] The support members 13 connect the core body 11 and the split core members 12 and support the split core members 12 on the core body 11. At this time, the support members 13 ensure a distance between the core body 11 and the split core members 12 to form accommodating chambers 18. As a result, the core body 11 and the split core members 12 are supported by the support members 13 and form accommodating chambers 18 of a predetermined shape between their opposing surfaces. In the embodiment shown in FIGS. 1 and 2, the rotating electric machine core 10 has 12 accommodating chambers 18 arranged circumferentially, and each accommodating chamber 18 accommodates one permanent magnet 14, for a total of 12 permanent magnets 14. The support members 13 are made of a magnetically insulating material. Examples of magnetically insulating materials that can be used to form the support members 13 include aluminum, stainless steel, and resin.

[0013] The core body 11 has first groove portions 21. The split core members 12 have second groove portions 22. The first groove portions 21 are provided in the core body 11 and are recessed circumferentially or radially from the outer wall 31 that forms the recess 16 of the core body 11, as shown in FIG. 3 . Specifically, the first groove portions 21 are recessed circumferentially or radially from the outer wall 31 of the core body 11 that faces the split core members 12. More specifically, of the first groove portions 21 provided in the core body 11, those whose depth direction coincides with the radial direction are recessed radially from the outer wall 31, while the other first groove portions 21 are recessed circumferentially from the outer wall 31. The first groove portions 21 extend in the axial direction of the core body 11, as shown in FIG. 1 . On the other hand, the second groove portions 22 are provided in the split core members 12 and are recessed circumferentially or radially from the opposing surface 32 of the split core member 12. Specifically, the second groove portions 22 are recessed in the circumferential direction or radial direction from the opposing surface 32 of the split core member 12 that faces the core body 11. More specifically, of the second groove portions 22 provided in the split core member 12, those whose depth direction coincides with the radial direction are recessed in the radial direction from the opposing surface 32, while the other second groove portions 22 are recessed in the circumferential direction from the opposing surface 32. Like the first groove portions 21, the second groove portions 22 extend in the axial direction in the split core member 12.

[0014] As shown in Fig. 3, the support member 13 has a first head portion 41 and a second head portion 42. The first head portion 41 is inserted into the first groove portion 21 of the core body 11. The second head portion 42 is inserted into the second groove portion 22 of the split core member 12. As a result, one end of the support member 13 is held in the first groove portion 21 of the core body 11, and the other end is held in the second groove portion 22 of the split core member 12, in the circumferential direction of the rotating electric machine core 10. In this way, the support member 13 connects the core body 11 and the split core members 12.

[0015] The first head 41 and the second head 42 each have a substantially trapezoidal cross section perpendicular to the axis. The cross section perpendicular to the axis of the first head 41 and the second head 42 is not limited to a substantially trapezoidal shape, and may have any shape, such as a circle or a polygon. In the embodiment shown in FIG. 3 , support members 13 are provided at one end and the other end of the split core member 12 in the circumferential direction, and at the end closest to the center in the radial direction. Therefore, in this embodiment, the core body 11 and the split core member 12 are supported by three support members 13.

[0016] The first head 41 of the support member 13 is inserted into the first groove 21. At this time, the support member 13 is held on the core body 11 by the first head 41 engaging with the first groove 21. The support member 13 may also be configured to be held on the core body by press-fitting the first head 41 into the first groove 21. Alternatively, if the support member 13 is made of a material with relatively high friction, such as resin, the core body 11 and the support member 13 may be held together by frictional force. Similarly, the second head 42 of the support member 13 is inserted into the second groove 22. At this time, the support member 13 is held on the split core member 12 by the second head 42 engaging with the second groove 22. The support member 13 may also be configured to be held on the split core member by press-fitting the second head 42 into the second groove 22. Alternatively, the split core member 12 and the support member 13 may be held together by frictional force.

[0017] As shown in FIG. 4 , the first groove portion 21 has a pair of side walls 44 that face each other in a direction perpendicular to the axial direction in which the first groove portion 21 extends. These side walls 44 contact the first head portion 41 of the support member 13. The side walls 44 are formed so that the angle A formed with the outer wall 31 is not perpendicular but is slightly inclined. For example, the angle A formed between the side walls 44 and the outer wall 31 of the core body 11 is 45°≦A. By setting the angle A in this way, when the cross section of the first head portion 41 perpendicular to the axis is trapezoidal, the first head portion 41 of the support member 13 can be easily inserted into the first groove portion 21.

[0018] In the rotating electric machine core 10 of one embodiment, the core main body 11 and the core segments 12 are supported by support members 13 made of a magnetically insulating material. Therefore, the core main body 11 and the core segments 12 are magnetically insulated by the support members 13. This reduces leakage of magnetic flux generated by the permanent magnets 14.

[0019] In the embodiment described above, the rotating electric machine core 10 is divided into a core main body 11 and core segments 12. The core main body 11 and core segments 12 are supported by support members 13 while maintaining a distance between them. As a result, housing chambers 18 that house permanent magnets 14 are formed between the core main body 11 and the core segments 12, and the core main body 11 and the core segments 12 are magnetically insulated by the support members 13. This reduces leakage of magnetic flux generated by the permanent magnets 14. Therefore, in an IPM-type rotating electric machine core 10 that houses permanent magnets 14 therein, magnetic flux leakage is reduced, enabling improved efficiency.

[0020] Furthermore, the rotating electric machine core 10 of one embodiment is divided into the core body 11 and the core segments 12. This allows for greater freedom in the shapes of the core body 11 and the core segments 12 compared to conventional rotating electric machine cores 10 formed by stacking disc-shaped steel plates. That is, in one embodiment, the steel plates constituting the rotating electric machine core 10 are not limited to being disc-shaped, as in conventional rotating electric machine cores. In one embodiment, the core body 11 and the core segments 12 are divided. Therefore, the steel plates 50 constituting the core body 11 may be formed into a substantially fan-shaped plate shape divided circumferentially at a central angle of 90°, as shown by the dashed line in FIG. 5 . The core body 11 can then be formed by combining fan-shaped columns formed by stacking the steel plates 50 in the circumferential direction. As a result, in one embodiment, compared to the conventional example in which a circular laminated steel plate is punched out from a single electromagnetic steel plate, more steel plate 50 constituting core body 11 and steel plate for segment core members 12 can be obtained from a single electromagnetic steel plate. Therefore, the electromagnetic steel plate material can be used efficiently, which allows for the downsizing of equipment and the reduction of waste material.

[0021] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0022] In the drawings, 10 denotes a rotating electric machine iron core, 11 denotes the iron core body, 12 denotes divided iron core members, 13 denotes a support member, 14 denotes a permanent magnet, 16 denotes a recess, 17 denotes an outer peripheral wall, 18 denotes an accommodating chamber, 21 denotes a first groove portion, 22 denotes a second groove portion, 31 denotes an outer wall, 32 denotes an opposing surface, 41 denotes a first head portion, 42 denotes a second head portion, and 44 denotes a side wall.

Claims

1. An iron core body, a plurality of recesses provided in the circumferential direction of the core body, the recesses being cut out radially inward from the outer peripheral wall of the core body to have a V-shaped cross section in the axial direction; a split core member provided separately from the core body, attached to the recess, and forming an accommodation chamber for accommodating a permanent magnet between the split core member and a V-shaped outer wall of the core body that forms the recess; a support member that connects the core body and the split core members and supports the split core members on the core body while ensuring a distance between the core body and the split core members to form the accommodating chambers; A rotating electric machine core comprising:

2. The support member is formed of a magnetic insulating material. The rotating electric machine core according to claim 1.

3. the core body has a first groove portion recessed from the outer wall in a circumferential or radial direction and extending in an axial direction, The split core members have second groove portions recessed in the circumferential or radial direction and extending in the axial direction on opposing surfaces facing the outer wall, The support member has, between the opposing core body and the split core members, a first head portion at an end portion on the core body side that is inserted into the first groove portion, and a second head portion at an end portion on the split core member side that is inserted into the second groove portion. The rotating electric machine core according to claim 1.

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