JP2008167520A - Rotating electric machine - Google Patents

Abstract

A loss generated when an eddy current flows in an in-plane direction perpendicular to a rotation axis direction is efficiently reduced.
A rotor core 16 includes a laminated core portion 36 in which electromagnetic steel plates are laminated in the direction of the rotation axis of a rotor 14, and a dust core portion 46 disposed near a permanent magnet 18 and formed of a dust core material. The specific resistance in the in-plane direction perpendicular to the rotation axis direction is higher in the proximity portion of the permanent magnet 18 than in the other portions. The magnetic flux flowing in the direction of the rotation axis in the vicinity of the permanent magnet 18 fluctuates by partially disposing the dust core 46 having a high specific resistance in the in-plane direction in the vicinity of the permanent magnet 18 where the magnetic flux easily flows in the direction of the rotation axis. In this case, the eddy current flowing in the in-plane direction can be efficiently reduced.
[Selection] Figure 2

Description

  The present invention relates to a rotating electrical machine in which a stator and a rotor are disposed so as to face each other in a radial direction perpendicular to the rotation axis direction of the rotor.

  The related art of this type of rotating electrical machine is disclosed in Patent Document 1 below. In Patent Document 1, electromagnetic steel plates are laminated in the direction of the rotor's rotation axis to form a rotor core, and a plurality of magnets are punched and formed in the rotor core in the circumferential direction to insert and hold magnets. is doing. And by at least doubling the number of magnet insertion grooves with respect to the number of poles, both improvement in characteristics and downsizing can be achieved. The process is shared and the same magnet is used. Further, when inserting a magnet into the magnet insertion groove, a magnetic block is superimposed on the magnet in the thickness direction and inserted into the magnet insertion groove.

  In addition, rotating electric machines according to Patent Documents 2 to 7 below are disclosed.

JP 2002-136209 A JP 2001-339922 A JP 2001-186699 A JP-A-2005-341655 JP 2002-44920 A JP 2006-158049 A JP 2005-328679 A

  When the magnetic flux flowing through the iron core in the in-plane direction perpendicular to the rotation axis direction of the rotor is saturated, the magnetic flux also flows out in the rotation axis direction. When the magnetic flux flowing in the rotation axis direction fluctuates, an eddy current flows in an in-plane direction perpendicular to the rotation axis direction, and loss (iron loss) due to the eddy current occurs. In Patent Document 1, no measures are taken to suppress the eddy current in the in-plane direction, and the loss generated when the eddy current flows in the in-plane direction increases. In particular, near the magnet in the rotor core and at the teeth tip portion facing the rotor in the stator core, the magnetic flux tends to flow in the direction of the rotation axis, and loss due to eddy current in the in-plane direction is likely to occur.

  An object of this invention is to provide the rotary electric machine which can reduce efficiently the loss which arises when an eddy current flows in the in-plane direction perpendicular | vertical to a rotating shaft direction.

  The rotating electrical machine according to the present invention employs the following means in order to achieve the above-described object.

  A rotating electrical machine according to the present invention includes a stator and a rotor in which a magnet is disposed on a rotor core, and the stator and the rotor are opposed to each other in a radial direction orthogonal to the rotation axis direction of the rotor. In this rotary electric machine, the rotor core is disposed in the vicinity of the magnet, and has a high specific resistance core portion in which the specific resistance in the in-plane direction perpendicular to the rotation axis direction is higher than other portions. And

  According to the present invention, when the magnetic flux flowing in the direction of the rotation axis fluctuates by partially disposing the high specific resistance core part in a portion where the magnetic flux easily flows in the direction of the rotation axis of the rotor in the rotor core. Eddy currents flowing in the in-plane direction perpendicular to the axial direction can be efficiently reduced. As a result, it is possible to efficiently reduce the loss that occurs when eddy current flows in the in-plane direction.

  In one aspect of the present invention, it is preferable that the high specific resistance iron core is disposed at at least one end of the rotor iron core in the rotation axis direction. According to this aspect, the high specific resistance core portion can be more efficiently disposed in a portion where the magnetic flux easily flows in the rotation axis direction in the rotor core.

  In one aspect of the present invention, the high specific resistance iron core is formed of a powder magnetic core material, and a portion other than the high specific resistance iron core in the rotor core is formed by laminating electromagnetic steel sheets in the rotation axis direction. It is suitable that it is configured.

  The rotating electrical machine according to the present invention includes a stator and a rotor in which a magnet is disposed on a rotor core, and the stator and the rotor are arranged in a radial direction orthogonal to the rotation axis direction of the rotor. In the rotating electrical machine arranged opposite to each other, a path of an eddy current flowing in the in-plane direction perpendicular to the rotation axis direction is divided in the vicinity of the magnet in the rotor core when the magnetic flux flowing in the rotation axis direction fluctuates. The gist is that eddy current path dividing means is provided.

  According to the present invention, the eddy current path dividing means is partially disposed at a portion of the rotor core where the magnetic flux easily flows in the direction of the rotation axis of the rotor, thereby rotating when the magnetic flux flowing in the direction of the rotation axis fluctuates. The path of eddy current flowing in the in-plane direction perpendicular to the axial direction can be divided. As a result, it is possible to efficiently reduce the loss that occurs when eddy current flows in the in-plane direction.

  In one aspect of the present invention, it is preferable that the eddy current path dividing means is disposed at at least one end of the rotor core in the rotation axis direction. According to this aspect, it is possible to more efficiently arrange the eddy current path dividing means in a portion where the magnetic flux easily flows in the rotation axis direction in the rotor core.

  In one aspect of the present invention, it is preferable that a slit is provided as the eddy current path dividing means. In this aspect, the high specific resistance core portion whose specific resistance in the in-plane direction is higher than that of the other portion of the rotor core is provided in the slit, which is given to the flow of magnetic flux in the rotor core. The influence can be reduced.

  The rotating electrical machine according to the present invention includes a stator having teeth formed on a stator core and coils disposed on the teeth, and a rotor, and the teeth tip and the rotor are rotating shafts of the rotor. The stator iron core is disposed at the tip end portion of the teeth and has a higher specific resistance in the in-plane direction perpendicular to the rotation axis direction than other portions. The gist is to have a high resistivity core.

  According to the present invention, when the magnetic flux flowing in the direction of the rotational axis fluctuates by partially disposing the high specific resistance core part in the portion where the magnetic flux easily flows in the direction of the rotational axis of the rotor in the stator core. Eddy currents flowing in the in-plane direction perpendicular to the axial direction can be efficiently reduced. As a result, it is possible to efficiently reduce the loss that occurs when eddy current flows in the in-plane direction.

  In one aspect of the present invention, it is preferable that the high specific resistance iron core is disposed at at least one end of the tooth in the rotation axis direction. According to this aspect, the high specific resistance core portion can be more efficiently disposed in a portion where the magnetic flux easily flows in the direction of the rotation axis in the stator core.

  In one aspect of the present invention, the high resistivity core portion is formed of a powder magnetic core material, and a portion other than the high resistivity core portion in the stator core is obtained by laminating electromagnetic steel sheets in the rotation axis direction. It is suitable that it is configured.

  The rotating electrical machine according to the present invention includes a stator having teeth formed on a stator core and coils disposed on the teeth, and a rotor, and the teeth tip and the rotor are rotating shafts of the rotor. The rotating electrical machine is disposed opposite to the radial direction perpendicular to the direction, and an eddy current that flows in an in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction fluctuates at the tip of the teeth. The gist is that eddy current path dividing means for dividing the path is provided.

  According to the present invention, the eddy current path dividing means is partially disposed in a portion where the magnetic flux easily flows in the direction of the rotation axis of the rotor in the stator core, so that the rotation is performed when the magnetic flux flowing in the direction of the rotation axis fluctuates. The path of eddy current flowing in the in-plane direction perpendicular to the axial direction can be divided. As a result, it is possible to efficiently reduce the loss that occurs when eddy current flows in the in-plane direction.

  In one aspect of the present invention, it is preferable that the eddy current path dividing means is disposed at at least one end portion of the tooth in the rotation axis direction. According to this aspect, it is possible to more efficiently arrange the eddy current path dividing means in the portion where the magnetic flux easily flows in the rotation axis direction in the stator core.

  In one aspect of the present invention, it is preferable that a slit is provided as the eddy current path dividing means. In this aspect, the high specific resistance core portion whose specific resistance in the in-plane direction is higher than that of other portions in the stator core is provided in the slit, so that the magnetic flux flows in the stator core. The influence can be reduced.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

“Embodiment 1”
1 and 2 are diagrams illustrating a schematic configuration of the rotating electrical machine according to the first embodiment of the present invention. FIG. 1 shows an outline of the internal configuration of the stator 12 and the rotor 14 as seen from a direction orthogonal to the axis 22, and FIG. 2 shows the stator 12 and the rotor 14 as seen from a direction parallel to the axis 22. A part of the internal configuration is shown. The rotating electrical machine according to the present embodiment includes a stator (stator) 12 fixed to a casing (not shown), a rotor (rotor) 14 that is disposed on the radially inner side of the stator 12 and is rotatable with respect to the stator 12, Is provided.

  The rotor 14 includes a rotor core (rotor core) 16 and a plurality of permanent magnets 18 disposed on the outer periphery of the rotor core 16. The plurality of permanent magnets 18 are arranged at intervals along the circumferential direction of the rotor 14. A shaft center 22 is disposed on the rotor 14 along its rotation center axis, and the shaft center 22 is rotatably supported by the casing.

  The stator 12 includes a stator core (stator core) 26 and a plurality of stator coils 28 disposed on the stator core 26. A plurality of teeth 30 protruding radially inward (rotor 14 side) are arranged on the stator core 26 at intervals along the circumferential direction of the stator 12. The teeth 30 are disposed.

  The inner peripheral portion (teeth tip portion 30a) of the stator core 26 and the permanent magnet 18 (the outer peripheral portion of the rotor core 16) are in the direction of the rotation axis of the rotor 14 (the longitudinal direction of the axis 22, hereinafter simply referred to as the rotation axis direction). To the radial direction orthogonal to. The teeth 30 are sequentially magnetized by sequentially passing current through the stator coils 28, and a rotating magnetic field is formed. Then, the magnetic field flux of the permanent magnet 18 of the rotor 14 interacts with this rotating magnetic field, so that attraction and repulsion occurs, the rotor 14 rotates, and magnet torque can be obtained. 1 and 2, the rotor core 16 is also disposed on the surface of the permanent magnet 18 (outside of the permanent magnet 18 in the radial direction of the rotor 14). An example embedded inside is shown. In this example, reluctance torque can be obtained in addition to magnet torque. FIG. 2 shows an example in which the permanent magnets 18 are arranged in a V shape, but the arrangement of the permanent magnets 18 is not limited to this example.

  In the present embodiment, the rotor iron core 16 is constituted by a laminated iron core portion 36 in which thin silicon steel plates (magnetic steel plates) are laminated in the rotation axis direction, and a dust core portion 46 formed of a dust core material. Yes. The dust core material here is a material obtained by compacting a powder coated with a film that does not conduct electricity on the surface of fine particles of ferromagnetic material such as iron. The dust core portion 46 is disposed in the vicinity of the permanent magnet 18 in the rotor core 16, and a portion other than the dust core portion 46 (in the vicinity of the permanent magnet 18) in the rotor core 16 is a laminated core portion 36. Yes. Further, the dust core portion 46 near the permanent magnet 18 is disposed from one end portion to the other end portion in the rotation axis direction. In FIG. 2, the dust core 46 is disposed in the radially outer proximity portion (V-shaped valley portion) of the permanent magnet 18 arranged in a V shape and the radially inner proximity portion of the permanent magnet 18. An example of arrangement is shown.

  In the laminated iron core portion 36, the electrical steel sheets are laminated in the rotation axis direction, so that the specific resistance (electric resistance) in the rotation axis direction is high, but the specific resistance in the in-plane direction perpendicular to the rotation axis direction is Lower. On the other hand, the dust core portion 46 formed of the dust core material passes the magnetic flux in the three-dimensional direction, but hardly passes the current. Therefore, in the powder magnetic core 46, the specific resistance not only in the rotation axis direction but also in the in-plane direction perpendicular to the rotation axis direction increases. As a result, in the rotor core 16, the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is the other portion (laminated core portion) of the proximity portion (the dust core portion 46) of the permanent magnet 18. 36). As described above, in the present embodiment, the specific resistance in the in-plane direction perpendicular to the rotation axis direction is set higher than the other portions in the rotor core 16, which are disposed near the permanent magnet 18 in the rotor core 16. The high specific resistance iron core part is constituted by the dust core part 46.

  When the rotor iron core 16 is configured by laminating electromagnetic steel plates in the rotation axis direction, the magnetic resistance in the rotation axis direction is higher than the magnetic resistance in the in-plane direction perpendicular to the rotation axis direction. However, when the magnetic flux flowing in the in-plane direction within the rotor core 16 is saturated, the magnetic flux also flows out in the direction of the rotation axis. Here, FIG. 3 shows a result obtained by analyzing (numerical calculation) a part where the inventor of the present application generates a large amount of magnetic flux flowing in the rotation axis direction. As shown in the analysis result of FIG. 3, a large amount of magnetic flux flowing in the direction of the rotation axis is generated in the vicinity of the permanent magnet 18 in the rotor core 16. Further, especially in the vicinity of the permanent magnet 18, a large amount of magnetic flux flowing in the direction of the rotation axis is generated at the end of the rotor core 16 in the direction of the rotation axis. In FIG. 3, a portion 52 that is an adjacent portion (V-shaped valley portion) of the N-pole magnet 18 n arranged in a V shape and is an end portion in the rotation axis direction extends from the rotor core 16 to the outside in the rotation axis direction. A part 54 from which a large amount of magnetic flux flows out, and a part 54 that is an adjacent part (V-shaped valley part) of the S-pole magnet 18s arranged in a V-shape and is an end part in the rotation axis direction, is externally provided to the rotor core 16. This is a portion where a large amount of magnetic flux enters in the direction of the rotation axis.

  In the case where the dust core 46 is not provided (the rotor core 16 is composed only of the laminated core 36), when the magnetic flux flowing through the rotor core 16 is saturated, the magnetic core 46 is close to the permanent magnet 18. Magnetic flux flows out in the direction of the rotation axis. In particular, when the torque of the rotor 14 is large, the magnetic flux flowing in the rotor core 16 is easily saturated, and the magnetic flux easily flows in the direction of the rotation axis. When the magnetic flux flowing in the rotation axis direction fluctuates in the rotor core 16 (proximal part of the permanent magnet 18), for example, as shown in FIG. 4, an eddy current 34 flows in the in-plane direction perpendicular to the rotation axis direction. Thus, a loss (iron loss) due to the eddy current 34 occurs. In the laminated core portion 36, since the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is low, the in-plane eddy current 34 generated with the fluctuation of the magnetic flux flowing in the rotation axis direction also increases. Cheap.

  On the other hand, in the present embodiment, in the vicinity of the permanent magnet 18 in the rotor core 16, the specific resistance in the in-plane direction perpendicular to the rotation axis direction is the laminated core portion 36 (the other portion in the rotor core 16). A higher dust core 46 is disposed. As described above, the dust core 46 having a high specific resistance in the in-plane direction is partially disposed at a portion where the magnetic flux easily flows in the rotation axis direction in the rotor core 16. The eddy current 34 flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction fluctuates in the vicinity of the magnet 18) can be efficiently reduced. As a result, the loss due to the eddy current 34 in the in-plane direction can be efficiently reduced, and high efficiency of the rotating electrical machine can be realized.

  In the present embodiment, for example, as shown in FIG. 5, a dust core 46 may be disposed between the permanent magnets 18 arranged at intervals along the circumferential direction of the rotor 14. Thereby, when the magnetic flux flowing in the direction of the rotation axis fluctuates between the permanent magnets 18, the eddy current flowing in the in-plane direction perpendicular to the rotation axis direction can be efficiently reduced.

  Further, as described above, a large amount of magnetic flux that flows in the direction of the rotation axis is generated at the end of the rotor core 16 in the direction of the rotation axis, particularly in the vicinity of the permanent magnet 18 that is a portion where the magnetic flux easily flows in the direction of the rotation axis. is doing. Therefore, in the present embodiment, for example, as shown in FIGS. 6 to 9, among the adjacent portions of the permanent magnet 18, a dust core 46 is partially provided at at least one end of the rotor core 16 in the rotation axis direction. It can also be arranged. Here, FIG. 6 shows an outline of the internal configuration of the rotor 14 viewed from a direction orthogonal to the axis 22, FIG. 7 shows a part of the AA cross section of FIG. 6, and FIG. FIG. 9 shows a part of the CC cross section of FIG. 6. According to the configuration examples shown in FIGS. 6 to 9, the dust core portion 46 having a high specific resistance in the in-plane direction is more efficiently disposed in a portion where the magnetic flux easily flows in the rotation axis direction in the rotor core 16. Can do. 6 to 9 show examples in which dust cores 46 are disposed at both ends of the rotor core 16 in the direction of the rotation axis. However, the dust core part 46 can also be disposed at one end or the other end of the rotor core 16 in the rotation axis direction.

  In the above description of the first embodiment, it is assumed that the rotor core 16 is also disposed on the surface (magnetic pole surface) of each permanent magnet 18. However, in this embodiment, the surface of each permanent magnet 18 may be exposed on the surface (outer peripheral surface) of the rotor 14. Even in this case, in the in-plane direction, the dust core part 46 having a high specific resistance in the in-plane direction is partially disposed in the vicinity of the permanent magnet 18 in which the magnetic flux easily flows in the rotation axis direction in the rotor core 16. Loss due to eddy current can be efficiently reduced.

“Embodiment 2”
FIG. 10 is a diagram showing a schematic configuration of the rotating electrical machine according to the second embodiment of the present invention, and shows a part of the internal configuration of the rotor 14 viewed from the direction parallel to the axis 22. In the following description of the second embodiment, the same or corresponding components as those in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  In this embodiment, as compared with the first embodiment, the rotor core 16 is configured by laminating electromagnetic steel plates in the rotation axis direction, and a plurality of slits (gaps) are provided near the permanent magnet 18 in the rotor core 16. 48) is formed. FIG. 10 shows an example in which a slit 48 is formed in a proximal portion (V-shaped valley portion) on the radially outer side of the permanent magnet 18 arranged in a V shape. The slit 48 here divides the path of the eddy current flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction in the rotor core 16 (proximal part of the permanent magnet 18) fluctuates. Play a role. The longitudinal direction of each slit 48 is preferably set in a direction that is orthogonal to the in-plane eddy current direction and that has less influence on the flow of magnetic flux in the rotor core 16. In the example shown in FIG. 10, the longitudinal direction of each slit 48 is parallel (or substantially parallel) to the normal direction of the magnetic pole surface of the permanent magnet 18 adjacent thereto. In the example shown in FIG. 10, since the normal direction of the magnetic pole surface of the permanent magnet 18 is inclined in the circumferential direction of the rotor 14 with respect to the radial direction of the rotor 14, the longitudinal direction of each slit 48 is also rotated. The rotor 14 is inclined in the circumferential direction with respect to the radial direction of the rotor 14.

  In the present embodiment, the slit 48 is partially formed in a portion where the magnetic flux easily flows in the rotation axis direction in the rotor core 16. By dividing the path of the eddy current in the in-plane direction by the slit 48, the cross-sectional area (area in the in-plane direction) of the portion where the eddy current circulates is reduced. Therefore, the eddy current flowing in the rotor core 16 in the in-plane direction can be efficiently reduced, and the loss due to the eddy current in the in-plane direction can be efficiently reduced.

  In the present embodiment, for example, as shown in FIG. 11, each slit 48 can be filled with the dust core 46 of the first embodiment. Also in the rotor core 16 shown in FIG. 11, as in the first embodiment, the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is higher in the dust core portion 46 than in the other portions. Become. Therefore, also in the configuration example shown in FIG. 11, the eddy current flowing in the in-plane direction within the rotor core 16 can be efficiently reduced. Further, in the configuration example shown in FIG. 11, by providing the dust cores 46 in the respective slits 48, it is possible to prevent a decrease in the magnetic permeability in the respective slits 48. The influence on the flow of magnetic flux can be further reduced.

  In this embodiment, for example, as shown in FIG. 12, the longitudinal direction of each slit 48 can be set parallel (or substantially parallel) to the radial direction of the rotor 14. In the example shown in FIG. 12, since the normal direction of the magnetic pole surface of the permanent magnet 18 is inclined in the circumferential direction of the rotor 14 with respect to the radial direction of the rotor 14, the longitudinal direction of each slit 48 is close thereto. The permanent magnet 18 is inclined in the circumferential direction of the rotor 14 with respect to the normal direction of the magnetic pole surface of the permanent magnet 18. The slit 48 shown in FIG. 12 also provides a path of eddy current flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction in the rotor core 16 (proximal part of the permanent magnet 18) fluctuates. Can be divided.

  Further, in the present embodiment, for example, as shown in FIG. 13, slits are provided between the adjacent portions on the radially inner side of the permanent magnet 18 and between the permanent magnets 18 arranged at intervals along the circumferential direction of the rotor 14. 48 can also be formed. FIG. 13 shows an example in which the longitudinal direction of each slit 48 is parallel to the radial direction of the rotor 14. Also in the configuration example shown in FIG. 13, eddy currents flowing in the in-plane direction through the rotor core 16 can be efficiently reduced.

  Further, in the present embodiment, like the dust core portion 46 of the first embodiment, the slit 48 is partially provided at at least one end portion of the rotor core 16 in the rotation axis direction in the proximity portion of the permanent magnet 18. It can also be formed. As a result, the slit 48 can be more efficiently formed at a portion of the rotor core 16 where the magnetic flux easily flows in the rotation axis direction. Here, the slits 48 can be formed at both ends of the rotor core 16 in the rotation axis direction, and the slits 48 can be formed at one end or the other end of the rotor core 16 in the rotation axis direction.

  Also in this embodiment, as in the first embodiment, the surface of each permanent magnet 18 may be exposed on the surface (outer peripheral surface) of the rotor 14. Even in this case, the loss due to the eddy current in the in-plane direction can be efficiently reduced by partially forming the slit 48 near the permanent magnet 18 where the magnetic flux easily flows in the direction of the rotation axis in the rotor core 16. .

“Embodiment 3”
14 and 15 are diagrams showing a schematic configuration of the rotating electrical machine according to the third embodiment of the present invention. FIG. 14 shows an outline of the internal configuration of the stator 12 and the rotor 14 as seen from a direction orthogonal to the axis 22, and FIG. 15 shows a stator core 26 (tooth 30) as seen from a direction parallel to the axis 22. A part of the configuration is shown. In the following description of the third embodiment, the same or corresponding components as those of the first and second embodiments are denoted by the same reference numerals, and redundant description is omitted.

  In the present embodiment, the stator core 26 includes a laminated core portion 56 in which electromagnetic steel plates are laminated in the rotation axis direction, and a dust core portion 66 formed of a dust core material. The dust core portion 66 is disposed at the tooth tip portion 30 a of the stator core 26, and a portion other than the dust core portion 66 (tooth tip portion 30 a) of the stator core 26 is a laminated core portion 56. Yes. Further, the dust core portion 66 of the tooth tip portion 30a is disposed from one end portion to the other end portion in the rotation axis direction. 14 shows an example in which the dust core portion 46 is disposed in the vicinity of the permanent magnet 18 in the rotor core 16, the dust core portion 46 can be omitted.

  In the laminated iron core portion 56, the electrical steel sheets are laminated in the rotation axis direction, so that the specific resistance (electric resistance) in the rotation axis direction is high, but the specific resistance in the in-plane direction perpendicular to the rotation axis direction is Lower. On the other hand, the dust core portion 66 allows the magnetic flux to pass in the three-dimensional direction, but hardly passes an electric current. Therefore, the specific resistance not only in the rotation axis direction but also in the in-plane direction perpendicular to the rotation axis direction is increased. As a result, in the stator core 26, the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is the other portion (laminated core portion 56) of the tooth tip portion 30a (dust core portion 66). Higher than. As described above, in the present embodiment, the specific resistance in the in-plane direction perpendicular to the rotation axis direction is set higher than that of the other portions of the stator core 26, which is disposed at the teeth tip 30a of the stator core 26. The high specific resistance iron core part is constituted by the dust core part 66.

  When the stator core 26 is configured by stacking electromagnetic steel plates in the rotation axis direction, the magnetic resistance in the rotation axis direction is higher than the in-plane direction magnetic resistance perpendicular to the rotation axis direction. However, when the magnetic flux flowing in the in-plane direction within the stator core 26 is saturated, the magnetic flux flows in the direction of the rotation axis at the tooth tip 30a. In particular, when the torque of the rotor 14 is large, the magnetic flux flowing in the stator core 26 is likely to be saturated. Then, in the stator core 26 (tooth tip 30a), when the magnetic flux flowing in the rotation axis direction fluctuates, an eddy current flows in an in-plane direction perpendicular to the rotation axis direction, and loss due to this eddy current occurs. In the case where the dust core 66 is not provided (the stator core 26 is constituted only by the laminated core 56), since the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is low, the rotation axis direction The eddy current in the in-plane direction that is generated along with the fluctuation of the magnetic flux flowing through the plate tends to increase.

  On the other hand, in the present embodiment, the teeth distal end portion 30a of the stator core 26 has a specific resistance in the in-plane direction perpendicular to the rotation axis direction than that of the laminated core portion 56 (other portions of the stator core 26). A high dust core 66 is provided. As described above, the dust core portion 66 having high specific resistance in the in-plane direction is partially disposed in a portion where the magnetic flux easily flows in the rotation axis direction in the stator core 26, so that the inside of the stator core 26 (the teeth). The eddy current flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction fluctuates through the tip 30a) can be efficiently reduced. As a result, the loss due to the eddy current in the in-plane direction can be efficiently reduced, and high efficiency of the rotating electrical machine can be realized.

  In addition, a large amount of magnetic flux flowing in the rotation axis direction is generated at the end of the stator core 26 (tooth 30) in the rotation axis direction, particularly in the tooth tip portion 30a, which is a portion where the magnetic flux easily flows in the rotation axis direction. . Therefore, in the present embodiment, for example, as shown in FIG. 16, the powder magnetic core portion 66 can be partially disposed at at least one end portion of the tooth 30 in the rotation axis direction in the tooth tip portion 30 a. . According to the configuration example shown in FIG. 16, the dust core portion 66 having a high specific resistance in the in-plane direction can be more efficiently disposed in a portion where the magnetic flux easily flows in the rotation axis direction in the stator core 26. . FIG. 16 shows an example in which dust cores 66 are disposed at both ends of the tooth 30 in the rotation axis direction. However, the dust core portion 66 may be disposed at one end or the other end of the tooth 30 in the rotation axis direction.

“Embodiment 4”
FIG. 17 is a diagram showing a schematic configuration of the rotating electrical machine according to the fourth embodiment of the present invention, and shows a part of the configuration of the stator core 26 (tooth 30) viewed from the direction parallel to the axis 22. As shown in FIG. In the following description of the fourth embodiment, the same or corresponding components as those in the first to third embodiments are denoted by the same reference numerals, and redundant description is omitted.

  In the present embodiment, the stator core 26 is configured by laminating electromagnetic steel plates in the rotation axis direction, and a plurality of slits (air gaps) 68 are formed in the tooth tip portion 30a of the stator core 26. The slit 68 here serves to divide the path of the eddy current flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction in the stator core 26 (tooth tip 30a) fluctuates. Fulfill. The longitudinal direction of each slit 68 is preferably set in a direction that is orthogonal to the in-plane eddy current direction and reduces the influence on the flow of magnetic flux in the stator core 26. FIG. 17 shows an example in which the longitudinal direction of each slit 68 is parallel (or substantially parallel) to the radial direction of the stator 12 (radial direction of the rotor 14).

  In the present embodiment, the slit 68 is partially formed in a portion of the stator core 26 where the magnetic flux easily flows in the rotation axis direction. By dividing the path of the eddy current in the in-plane direction by the slit 68, the cross-sectional area (area in the in-plane direction) of the portion where the eddy current circulates is reduced. Therefore, the eddy current flowing in the in-plane direction through the stator core 26 can be efficiently reduced, and the loss due to the eddy current in the in-plane direction can be efficiently reduced.

  In the present embodiment, for example, as shown in FIG. 18, the dust core 66 of the third embodiment can be filled in each slit 68. Also in the stator core 26 shown in FIG. 18, as in the third embodiment, the specific resistance (electric resistance) in the in-plane direction perpendicular to the rotation axis direction is higher in the dust core portion 66 than in the other portions. Become. Therefore, also in the configuration example shown in FIG. 18, the eddy current flowing in the in-plane direction through the stator core 26 can be efficiently reduced. Further, in the configuration example shown in FIG. 18, by arranging the powder magnetic core portion 66 in each slit 68, it is possible to prevent a decrease in the magnetic permeability in each slit 68. The influence on the flow of magnetic flux can be further reduced.

  Further, in the present embodiment, similarly to the dust core portion 66 of the third embodiment, a slit is formed in at least one end portion of the stator core 26 (tooth 30) in the rotation axis direction in the proximity portion of the tooth tip portion 30a. 68 can also be partially formed. As a result, the slit 68 can be more efficiently formed in the stator core 26 at a portion where the magnetic flux easily flows in the direction of the rotation axis. Here, the slits 68 can be formed at both ends of the tooth 30 in the rotation axis direction, and the slits 68 can be formed at one end or the other end of the tooth 30 in the rotation axis direction.

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to such embodiment at all, and it can implement with a various form in the range which does not deviate from the summary of this invention. Of course.

It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure explaining the site | part where much magnetic flux which flows into the rotating shaft direction of a rotor generate | occur | produces. It is a figure explaining the eddy current which flows into the in-plane direction perpendicular | vertical to the rotating shaft direction of a rotor. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 2 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 2 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 2 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 2 of this invention. It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 3 of this invention. It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 3 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 3 of this invention. It is a figure which shows schematic structure of the rotary electric machine which concerns on Embodiment 4 of this invention. It is a figure which shows the other schematic structure of the rotary electric machine which concerns on Embodiment 4 of this invention.

Explanation of symbols

  12 Stator, 14 Rotor, 16 Rotor Core, 18 Permanent Magnet, 22 Axis Center, 26 Stator Core, 28 Stator Coil, 30 Teeth, 30a Teeth Tip, 36, 56 Laminated Core, 46, 66 Pressure Powder magnetic core, 48, 68 slits.

Claims (14)

A rotating electrical machine comprising a stator and a rotor having magnets disposed on a rotor core, wherein the stator and the rotor are arranged to face each other in a radial direction perpendicular to the rotation axis direction of the rotor,
The rotor core is disposed in the vicinity of a magnet, and has a high specific resistance core portion having a higher specific resistance in an in-plane direction perpendicular to the rotation axis direction than other portions. The rotating electrical machine according to claim 1,
The high specific resistance core is a rotating electrical machine that is disposed at at least one end of the rotor core in the direction of the rotation axis. The rotating electrical machine according to claim 1 or 2,
The high specific resistance iron core is formed of a dust core material,
A portion of the rotor core other than the high specific resistance core is a rotating electrical machine configured by laminating electromagnetic steel plates in the direction of the rotation axis. A rotating electrical machine comprising a stator and a rotor having magnets disposed on a rotor core, wherein the stator and the rotor are arranged opposite to each other in a radial direction perpendicular to the rotation axis direction of the rotor,
In the vicinity of the magnet in the rotor core, eddy current path dividing means for dividing the eddy current path flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction fluctuates is disposed. The rotating electric machine. The rotating electrical machine according to claim 4,
The eddy current path dividing means is a rotating electrical machine disposed at at least one end of the rotor core in the rotation axis direction. The rotating electrical machine according to claim 4 or 5,
A rotating electrical machine in which a slit is disposed as an eddy current path dividing means. The rotating electrical machine according to claim 6,
A rotating electrical machine in which a high specific resistance core portion having a specific resistance in the in-plane direction higher than other portions of the rotor core is disposed in the slit. The stator includes a stator in which teeth are formed and coils are disposed in the teeth, and a rotor. The teeth tip and the rotor are arranged opposite to each other in a radial direction perpendicular to the rotation axis direction of the rotor. A rotating electric machine,
The stator core is a rotating electrical machine having a high specific resistance core portion that is disposed at a tooth tip portion and has a higher specific resistance in an in-plane direction perpendicular to the rotation axis direction than other portions. The rotating electrical machine according to claim 8,
The high specific resistance iron core is a rotating electrical machine that is disposed at at least one end of the tooth in the rotation axis direction. The rotating electrical machine according to claim 8 or 9,
The high specific resistance iron core is formed of a dust core material,
Parts other than the high specific resistance core part in the stator core are rotating electrical machines configured by laminating electromagnetic steel sheets in the rotation axis direction. The stator includes a stator in which teeth are formed on the stator core and coils are disposed on the teeth, and a rotor. The teeth tip and the rotor are arranged to face each other in a radial direction perpendicular to the rotation axis direction of the rotor. A rotating electric machine,
An eddy current path dividing means is provided at the tip of the tooth to divide the eddy current path flowing in the in-plane direction perpendicular to the rotation axis direction when the magnetic flux flowing in the rotation axis direction fluctuates. Electric. The rotating electrical machine according to claim 11,
The eddy current path dividing means is a rotating electrical machine disposed at at least one end of the tooth in the rotation axis direction. The rotating electrical machine according to claim 11 or 12,
A rotating electrical machine in which a slit is disposed as an eddy current path dividing means. The rotating electrical machine according to claim 13,
A rotating electrical machine in which a high specific resistance core portion having a specific resistance in the in-plane direction higher than that of other portions of the stator core is disposed in the slit.

Images