JP6873335B1 - Rotating machine - Google Patents

Abstract

Obtain a rotary electric machine capable of suppressing a decrease in output torque of the rotary electric machine. This rotating electric machine includes a stator and a rotor, and two different magnetic poles are formed side by side in the circumferential direction on the portion of the permanent magnet on the stator side, and the rotor core is formed in the circumferential direction. It has a rib sandwiched between a pair of permanent magnets adjacent to each other and a magnetic pole core portion provided in a region closer to the stator than the permanent magnet and connected to the rib, and is fixed in each of the pair of permanent magnets sandwiching the rib. The same magnetic poles are formed at the ends of the child side that are adjacent to each other in the circumferential direction, and the magnetism between the permanent magnet and the tooth on a straight line that passes between different poles and extends in the radial direction. The gap length is larger than the magnetic gap length between the rotor core and the tooth on a straight line extending radially through the rib.

Description

The present invention relates to a rotary electric machine.

Conventionally, a stator core including a tooth and a stator having a winding provided on the tooth, and a plurality of permanent magnets provided facing the stator and embedded in the rotor core and the rotor core and arranged in the circumferential direction. A rotating electric machine having a rotor having a magnet is known. Two different magnetic poles are arranged side by side in the circumferential direction on the stator side portion of the permanent magnet. The rotor core has a rib sandwiched between a pair of permanent magnets adjacent to each other in the circumferential direction, and a magnetic pole core portion provided on the stator side of the permanent magnet and connected to the rib. The same magnetic poles are arranged at the stator-side portions of each of the pair of permanent magnets sandwiching the rib and adjacent to each other in the circumferential direction. As a result, the portions on the stator side of each of the pair of permanent magnets sandwiching the rib and adjacent to each other in the circumferential direction form the same magnetic pole in the rotor. By arranging the ribs between a pair of permanent magnets forming the same magnetic pole in the rotor, the inductance of the magnetic circuit passing through the circumferential center portion of the magnetic pole of the rotor is increased. As a result, the field weakening control of the rotary electric machine can be performed by using a small current component. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 6-38475

However, the gap length between the permanent magnet and the tooth on a straight line extending radially through the different poles between the parts on the stator side of the permanent magnet and having different magnetic poles passes through the rib. It coincides with the gap length between the rotor core and the teeth on a straight line extending in the radial direction. As a result, a magnetic circuit having a high magnetic flux density is formed between the magnetic poles and the teeth, which are the portions of the permanent magnets arranged on a straight line extending in the radial direction through the different poles. Due to the armature reaction, a reverse magnetic field acts between the magnetic poles. As a result, demagnetization occurs in the interpole region. Therefore, the effective interlinkage magnetic flux that interlinks the windings is reduced. As a result, there is a problem that the output torque of the rotary electric machine is reduced.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a rotary electric machine capable of suppressing a decrease in output torque of the rotary electric machine.

The rotary electric machine according to the present invention is provided facing a stator core including a tooth and a stator having a winding provided on the tooth, and is embedded in the rotor core and the rotor core in the circumferential direction. A rotor having a plurality of arranged permanent magnets is provided, and a plurality of magnetic poles different from each other are arranged side by side in the circumferential direction on a portion of the permanent magnet on the stator side, and the rotor core is arranged in the circumferential direction. It has a rib sandwiched between a pair of permanent magnets adjacent to each other and a magnetic pole iron core portion provided on the stator side of the permanent magnet and connected to the rib, and between the permanent magnet and the rib in the circumferential direction. A gap is formed, and the surface facing the circumferential direction in the gap between the permanent magnet and the rib is composed of the surface of the permanent magnet and the surface of the rib, and is fixed in each of the pair of permanent magnets sandwiching the rib. The same magnetic poles are arranged at the ends of the child side that are adjacent to each other in the circumferential direction, and the different poles are between the parts of the permanent magnet on the stator side that have different magnetic poles. The magnetic gap length between the permanent magnet and the tooth on a straight line extending radially through the rib is the magnetic gap between the rotor core and the tooth on a straight line extending radially through the rib. Greater than length.

According to the rotary electric machine according to the present invention, it is possible to suppress a decrease in the output torque of the rotary electric machine.

It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 1 of this invention. It is a conceptual diagram which shows the rotary electric machine in the case of the field weakening control. It is an enlarged view which shows the part A of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 2 of this invention. It is an enlarged view which shows the part B of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 3 of this invention. It is an enlarged view which shows the part C of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 4 of this invention. It is an enlarged view which shows the part D of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 5 of this invention. It is an enlarged view which shows the part E of FIG. It is sectional drawing which shows the modification of the rotary electric machine of FIG. It is an enlarged view which shows the F part of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 6 of this invention. It is an enlarged view which shows the G part of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 7 of this invention. It is an enlarged view which shows the H part of FIG. It is sectional drawing which shows the rotary electric machine which concerns on Embodiment 8 of this invention. It is an enlarged view which shows the part I of FIG.

Embodiment 1.
FIG. 1 is a cross-sectional view showing a rotary electric machine according to a first embodiment of the present invention. The rotary electric machine includes a cylindrical front housing 1 and a stator 2 fixed to the inner peripheral surface of the front housing 1. Further, the rotary electric machine includes a rotary shaft 3 and a rotor 4 fixed to the rotary shaft 3 and rotating together with the rotary shaft 3. The rotor 4 is arranged inside the stator 2 in the radial direction of the rotor 4. In this example, the radial direction is the radial direction for the rotor 4, the circumferential direction is the circumferential direction for the rotor 4, and the axial direction is the axial direction for the rotor 4. FIG. 1 shows a cross section of a rotary electric machine that is perpendicular to the circumferential direction. The rotor 4 is provided so as to face the stator 2 in the radial direction.

The rotating shaft 3 is composed of a non-magnetic stainless steel shaft, a magnetic carbon steel shaft for mechanical structure, and the like. Examples of carbon steel for machine structure include S10C, S45C, SCM435 and the like.

The front housing 1 has a housing cylindrical portion 101 and a first bearing holding portion 102 connected to the housing cylindrical portion 101. The rotary electric machine includes a first bearing 5 held by the first bearing holding portion 102. The first bearing 5 rotatably supports the rotating shaft 3. The first bearing 5 is made of a magnetic material or a non-magnetic material.

The rotary electric machine includes an end frame 6 fixed to the front housing 1. The end frame 6 has an end frame base portion 601 and a second bearing holding portion 602 connected to the end frame base portion 601. The end frame base 601 is formed with an axial inner surface 603 facing the rotor 4 in the axial direction. The rotary electric machine includes a second bearing 7 held by the second bearing holding portion 602. The second bearing 7 rotatably supports the rotating shaft 3. The second bearing 7 is made of a magnetic material or a non-magnetic material. The second bearing 7 is arranged so as to project from the axial inner side surface 603 toward the rotor 4.

The rotor 4 has a rotor core 401 and a plurality of permanent magnets 402 embedded in the rotor core 401. The rotor core 401 is made of a soft magnetic material. Further, the rotor core 401 is composed of, for example, an electromagnetic steel plate, a dust core, or the like. The permanent magnet 402 is used as a field magnet for a rotating electric machine.

The stator 2 has a stator core 201. The stator core 201 includes a cylindrical core back 202 and a plurality of teeth 203 protruding inward in the radial direction from the core back 202. The core back 202 is fixed to the inner peripheral surface of the housing cylindrical portion 101. The plurality of teeth 203 are arranged side by side at equal pitches in the circumferential direction. The teeth 203 are formed so as to extend in the axial direction.

FIG. 2 is a cross-sectional view showing a rotary electric machine according to the first embodiment of the present invention. In FIG. 2, a cross section perpendicular to the axial direction of the rotary electric machine is shown. The teeth 203 is formed so that the cross-sectional shape perpendicular to the axial direction is a T-shape. The shape of the surface of the teeth 203 facing inward in the radial direction is an arc shape centered on the center of the rotor 4 when viewed along the rotation axis 3. The surfaces of the plurality of teeth 203 facing inward in the radial direction are arranged on the same circle centered on the center of the rotor 4 when viewed along the rotation axis 3.

The stator 2 has a plurality of insulators (not shown) provided on each of the plurality of teeth 203, and a plurality of windings 204 provided on each of the plurality of teeth 203 via the insulators. The plurality of windings 204 are divided into three phases. Specifically, the number of teeth 203 is 12, the number of U-phase windings 204 is 4, the number of V-phase windings 204 is 4, and the number of W-phase windings 204. The number of is four.

The U-phase winding 204 is the U-phase winding 204A, the V-phase winding 204 is the V-phase winding 204B, and the W-phase winding 204 is the W-phase winding 204C. Regarding the winding direction of the winding 204, the U-phase winding 204A is represented by U, the V-phase winding 204B is represented by V, the W-phase winding 204C is represented by W, the right-handed winding is represented by +, and the left-handed winding is represented by −. In this case, the 12 windings 204 are arranged in the circumferential direction in the order of U−, U +, V +, V−, W−, W +, U +, U−, V−, V +, W +, W−. The winding method of the 12 windings 204 is concentrated winding.

A drive current is supplied to each of the U-phase winding 204A, the V-phase winding 204B, and the W-phase winding 204C from a drive device (not shown). A rotating magnetic field is generated in the stator 2 by supplying a drive current to each of the U-phase winding 204A, the V-phase winding 204B, and the W-phase winding 204C. When a rotating magnetic field is generated in the stator 2, the rotor 4 rotates in the forward direction or the reverse direction.

In the first embodiment, the configuration of a 10-pole 12-slot rotary electric machine in which the number of magnetic poles of the rotor 4 is 10 and the number of windings 204 is 12 will be described. However, the configuration of this rotary electric machine is an example. The rotary electric machine may be a rotary electric machine different from the rotary electric machine having 10 poles and 12 slots.

As shown in FIG. 1, the rotary electric machine has a support case 8 provided on the rotor 4 and a plurality of sensor magnets 9 supported by the support case 8 and provided so as to face the axial inner side surface 603 in the axial direction. And a plurality of magnetic sensors 10 provided on the inner side surface 603 in the axial direction. The support case 8 is made of a non-magnetic material or a magnetic material. Examples of the non-magnetic material constituting the support case 8 include brass and brass. Examples of the magnetic material constituting the support case 8 include S45C and S10C.

The plurality of sensor magnets 9 are arranged side by side in the circumferential direction. The magnetic poles on the inner side surface 603 side in the axial direction of each of the plurality of sensor magnets 9 are north poles or south poles. The magnetic poles on the inner side surface 603 side in the axial direction of the sensor magnets 9 adjacent to each other in the circumferential direction are different from each other. The number of the plurality of sensor magnets 9 is n times the number of 10 magnetic poles of the rotor 4. Here, n is a natural number.

The magnetic sensor 10 is arranged so as to face the sensor magnet 9 at a certain interval in the axial direction. Examples of the magnetic sensor 10 include a Hall IC. The plurality of magnetic sensors 10 are arranged side by side in the circumferential direction. The number of magnetic sensors 10 is three. Each of the three magnetic sensors 10 is arranged at an electrical angle of 120 degrees. In this example, the magnetic sensor 10 is fixed to the end frame 6. The magnetic sensor 10 may be fixed to the end frame 6 via a holding member (not shown).

As the rotor 4 rotates, the N-pole magnetized portion and the S-pole magnetized portion of the sensor magnet 9 alternately face the magnetic sensor 10. The magnetic sensor 10 detects that the portion of the sensor magnet 9 magnetized at the north pole and the portion magnetized at the south pole alternately face the magnetic sensor 10.

The detection signal of the magnetic sensor 10 is output to a control circuit (not shown). The control circuit calculates the rotation angle or rotation position of the rotor 4 and the rotation number of the rotor 4 based on the detection signal of the magnetic sensor 10. The control circuit controls the drive of the rotating electric machine by using the rotation angle or the rotation position of the rotor 4 and the rotation number of the rotor 4. Note that the calculation of the rotation angle or rotation position of the rotor 4 and the rotation number of the rotor 4 does not use the detection signal of the position sensor provided with the sensor magnet 9 and the magnetic sensor 10, but uses the detection signal of the encoder, resolver, or the like. You may use it.

As shown in FIG. 2, the permanent magnet 402 is embedded in the rotor core 401. The rotor core 401 includes a magnetic pole core portion 403 provided radially outside the permanent magnet 402, a joint iron portion 404 provided radially inside the permanent magnet 402, and a magnetic pole core portion 403 and a joint iron portion. It has a plurality of ribs 405 that connect to the 404.

The permanent magnet 402 is radially sandwiched by the magnetic pole core portion 403 and the joint iron portion 404. The ribs 405 are arranged between a pair of permanent magnets 402 that are adjacent to each other in the circumferential direction. The outer peripheral surface of the rotor 4 is formed by a surface of the magnetic pole iron core portion 403 facing outward in the radial direction. A set gap is formed between the inner peripheral surface of the stator 2 and the outer peripheral surface of the rotor 4. The inner peripheral surface of the stator 2 and the outer peripheral surface of the rotor 4 do not come into contact with each other over the entire circumference.

In FIG. 2, the magnetic pole N and the magnetic pole S represent the magnetic poles of the radial outer portion of the permanent magnet 402. In one permanent magnet 402, the magnetic poles of the radial outer portions of the permanent magnet 402 are different from each other with the central portion in the circumferential direction of the permanent magnet 402 as a boundary. The permanent magnet 402 is formed by magnetizing one permanent magnet magnetic material in two directions. The permanent magnet 402 is magnetized in one direction with respect to each of the two permanent magnet magnetic bodies, and two magnetic poles of the radial outer portions of the two permanent magnet magnetic bodies are different from each other. It may be formed by arranging magnetic materials for permanent magnets adjacent to each other.

The plurality of permanent magnets 402 are arranged at equal intervals in the circumferential direction. Ribs 405 are arranged between a pair of permanent magnets 402 that are adjacent to each other in the circumferential direction. The magnetic poles of the portions of the pair of permanent magnets 402 that are adjacent to each other in the circumferential direction and that are adjacent to each other are the same. Therefore, the same magnetic poles are arranged at the ends of the pair of permanent magnets 402 that sandwich the rib 405 in the circumferential direction and that are adjacent to each other in the circumferential direction. In this example, with 10 permanent magnets 402 magnetized in two directions, the rotor 4 has magnetic poles with 5 N poles and 5 S poles. Further, a rib 405 is arranged at the center of each magnetic pole of the rotor 4 in the circumferential direction.

The magnetic permeability of the rotor core 401 is larger than the magnetic permeability of the permanent magnet 402. A rib 405 is arranged at the center of the magnetic pole of the rotor 4 in the circumferential direction. As a result, the inductance in the magnetic circuit that passes through the circumferential center of the rotor 4 magnetic pole is larger than that in the case where the rib 405 is not arranged at the circumferential center of the rotor 4 magnetic pole.

FIG. 3 is a conceptual diagram showing a rotary electric machine under field weakening control. In FIG. 3, the current component Id and the current component Iq are the currents of the respective phases when the currents of the respective phases supplied from the inverter to the winding 204 are coordinate-converted with reference to the rotating coordinates of the field magnetic flux Φm of the rotor 4. The ingredients are shown. The d-axis is in the same direction as the field magnetic flux Φm, and the q-axis is a direction advanced by 90 degrees in electrical angle with respect to the field magnetic flux Φm. The q-axis is in phase with the induced voltage.

The d-axis direction is the radial direction and is a direction that passes through the circumferential center of each magnetic pole. A magnetic pole iron core portion 403 is arranged at the center of the magnetic pole of the rotor 4 in the circumferential direction. Therefore, in the rotary electric machine of the first embodiment, the inductance Ld of the magnetic circuit passing through the circumferential center of the magnetic pole of the rotor 4 is compared with the rotary electric machine in which the permanent magnet 402 is arranged at the circumferential center of each magnetic pole. Becomes larger. As a result, in the rotary electric machine of the first embodiment, the magnetic circuit passing through the circumferential center of the magnetic pole of the rotor 4 is compared with the rotary electric machine in which the permanent magnet 402 is arranged at the circumferential center of each magnetic pole. , A large magnetic flux LdId is generated.

The magnetic flux Φd in the d-axis direction is a value obtained by combining the field magnetic flux Φm and the magnetic flux LdId. Therefore, by supplying a current to the winding 204 so that a current in the negative direction flows through the current component Id, the magnetic flux Φd in the d-axis direction becomes smaller than the field magnetic flux Φm.

FIG. 4 is an enlarged view showing a part A of FIG. The portion of the permanent magnet 402 on the stator 2 side, which has different magnetic poles from each other, is defined as a space between different poles. The portion of the permanent magnet 402 arranged on a straight line extending in the radial direction through the different poles is referred to as the different pole portion 406.

A recess 407 is formed on the surface of the magnetic pole core portion 403 provided on the outer side in the radial direction from the interpole portion 406 facing the stator 2. The gap length L1 between the rotor 4 and the stator 2 on the straight line extending between the different poles in the radial direction is the gap length L1 between the rotor 4 and the stator 2 on the straight line extending in the radial direction through the rib 405. It is larger than the gap length L2 between them. Therefore, the magnetic gap length between the permanent magnet 402 and the teeth 203 on the straight line extending radially through the different poles is the rotor core 401 and the teeth on the straight line extending radially through the rib 405. It is larger than the magnetic void length between 203. The portion of the magnetic pole core portion 403 arranged radially outside the rib 405 is the closest portion of the rotor 4 which is the portion closest to the stator 2.

The gap length L1 between the magnetic pole core portion 403 and the teeth 203 on the straight line extending in the radial direction through the different poles is the magnetic pole core portion 403 and the teeth on the straight line extending in the radial direction without passing between the different poles. It is larger than the gap length between 203. Therefore, the reluctance in the region between the different poles 406 and the teeth 203 is in the region between the magnetic pole core 403 and the teeth 203 on a straight line extending in the radial direction without passing between the different poles. It becomes larger than the magnetic resistance. As a result, the magnetic circuit formed between the different poles 406 and the teeth 203 is formed between the magnetic flux core portion 403 and the teeth 203 on a straight line extending in the radial direction without passing between the different poles. The magnetic flux density is lower than that of the formed magnetic circuit.

By lowering the magnetic flux density of the magnetic circuit formed between the different poles 406 and the teeth 203, the magnetic flux density of the magnetic pole core portion 403 arranged on a straight line extending in the radial direction without passing between the magnetic poles In comparison, the reverse magnetic field due to the reaction of the armature is less likely to act on the interpolar portion 406. As a result, demagnetization is less likely to occur in the interpole portion 406. As a result, the decrease in the effective interlinkage magnetic flux interlinking the winding 204 is suppressed, and the decrease in the output torque of the rotary electric machine is suppressed.

As described above, in the rotary electric machine according to the first embodiment of the present invention, the magnetic gap length between the permanent magnet 402 and the teeth 203 on a straight line extending in the radial direction through the different poles is ribbed. It is larger than the magnetic void length between the rotor core 401 and the teeth 203 on a straight line extending radially through 405. As a result, it is possible to suppress a decrease in the output torque of the rotary electric machine.

Embodiment 2.
FIG. 5 is a cross-sectional view showing a rotary electric machine according to a second embodiment of the present invention. FIG. 6 is an enlarged view showing a portion B of FIG. In FIG. 5, a cross section perpendicular to the axial direction of the rotary electric machine is shown. In the second embodiment, the magnetic pole iron core portion 403 is not provided on the radial side of the interpole portion 406. In other words, the magnetic pole iron core portion 403 is arranged so as to be displaced in the circumferential direction from the straight line extending in the radial direction through the different poles. Therefore, the magnetic gap length between the permanent magnet 402 and the teeth 203 on the straight line extending radially through the different poles is the rotor core and the teeth 203 on the straight line extending radially through the rib 405. Greater than the magnetic void length between and.

The magnetic pole core portion 403 is not arranged radially outside the interpole portion 406. As a result, in the magnetic circuit that enters from one magnetic pole to the other magnetic pole in one permanent magnet 402, the magnetic pole core portion 403 provided radially outside the one magnetic pole and the magnetic pole core portion 403 provided radially outside the other magnetic pole are provided. The magnetic pole iron core portion 403 is included. Further, the two magnetic pole core portions 403 included in the magnetic circuit that enters the other magnetic pole from one magnetic pole in one permanent magnet 402 are separated from each other in the circumferential direction. Therefore, the leakage flux Φx1 passing through the magnetic circuit that enters the other magnetic pole of the same permanent magnet 402 from one magnetic pole of one permanent magnet 402 is reduced. Other configurations are the same as those in the first embodiment.

As described above, in the rotary electric machine according to the second embodiment of the present invention, similarly to the first embodiment, the decrease in the output torque of the rotary electric machine is suppressed by suppressing the demagnetization in the interpole portion 406. Can be done. Further, by reducing the leakage flux Φx1, it is possible to further suppress the decrease in the output torque of the rotary electric machine.

In the second embodiment, a configuration has been described in which the radial dimension of the magnetic pole iron core portion 403 at the circumferential end portion decreases toward the outer side in the circumferential direction. In other words, in the second embodiment, at the circumferential end portion of the magnetic pole iron core portion 403, the configuration in which the surface facing the radial outer side is arranged in the radial direction inward toward the circumferential outer side has been described. However, at the circumferential end portion of the magnetic pole iron core portion 403, the radial dimension may be constant regardless of the circumferential position. In other words, at the circumferential end of the magnetic pole core portion 403, when viewed in the axial direction, the surfaces facing outward in the radial direction may be arranged on the same circle regardless of the position in the circumferential direction.

Embodiment 3.
FIG. 7 is a cross-sectional view showing a rotary electric machine according to a third embodiment of the present invention. FIG. 8 is an enlarged view showing a portion C in FIG. 7. In FIG. 7, a cross section perpendicular to the axial direction of the rotary electric machine is shown. A magnetically hollow hole 408 is formed in a portion of the magnetic pole iron core portion 403 provided radially outside the interpole portion 406. The hole 408 penetrates the magnetic pole iron core portion 403 in the axial direction.

When viewed in the axial direction, the surface of the magnetic pole core portion 403 provided on the radial outer side of the interpolar portion 406 facing the radial outer side is the magnetic pole iron core provided on the radial outer side of the rib 405. It is arranged on the same circle as the surface of the portion 403 facing outward in the radial direction. In other words, unlike the second embodiment, the concave portion is not formed on the surface of the magnetic pole iron core portion 403 provided on the radial outer side of the interpolar portion 406 so as to face the radial outer side.

A magnetically hollow hole 408 is formed in a portion of a magnetic pole iron core portion 403 provided radially outside the interpole portion 406. As a result, the magnetic gap length between the permanent magnet 402 and the teeth 203 on the straight line extending radially through the different poles is the rotor core and the teeth on the straight line extending radially through the rib 405. It is larger than the magnetic void length between 203.

A magnetically hollow hole 408 is formed in a portion of a magnetic pole iron core portion 403 provided radially outside the interpole portion 406. As a result, the leakage flux Φx2 passing through the magnetic circuit from one magnetic pole of one permanent magnet 402 to the other magnetic pole of the same permanent magnet 402 via the teeth 203 is reduced. Other configurations are the same as those in the first embodiment.

As described above, according to the rotary electric machine according to the third embodiment of the present invention, as in the first embodiment, the decrease in the output torque of the rotary electric machine is suppressed by suppressing the demagnetization in the interpole portion 406. can do. Further, when viewed in the axial direction, the surface of the magnetic pole iron core portion 403 provided on the radial outer side of the interpolar portion 406 and facing the radial outer side is provided on the radial outer side of the rib 405. It is arranged on the same circle as the surface of the magnetic pole core portion 403 facing outward in the radial direction. Therefore, as compared with the first embodiment and the second embodiment, the unevenness on the outer peripheral surface of the rotor 4 is reduced. As a result, wind damage and noise generated in the rotary electric machine can be reduced.

Embodiment 4.
FIG. 9 is a cross-sectional view showing a rotary electric machine according to a fourth embodiment of the present invention. FIG. 10 is an enlarged view showing a portion D in FIG. In FIG. 9, a cross section perpendicular to the axial direction of the rotary electric machine is shown. The magnetic pole core portion 403 has a magnetic pole core central portion 409 provided at the central portion in the circumferential direction of the magnetic pole core portion 403, and a wall thickness changing portion 410 provided at both ends in the circumferential direction of the magnetic pole core portion 403. ..

At the central portion 409 of the magnetic pole core, the gap length between the rotor core 401 and the teeth 203 on the radially extending straight line is constant even when the radially extending straight line moves in the circumferential direction. ing. In the wall thickness changing portion 410, the gap length between the rotor core 401 and the teeth 203 on the radially extending straight line gradually decreases as the position of the radially extending straight line approaches the position passing through the rib 405. ing. At the end of the wall thickness changing portion 410 on the central portion 409 side of the magnetic pole core and the central portion 409 of the magnetic pole, the gap lengths between the rotor core 401 and the teeth 203 on a straight line extending in the radial direction are the same. ing.

In other words, the magnetic pole core portion 403 has a rib 405 from a position where the gap length between the rotor core 401 and the teeth 203 on a linearly extending radial direction passes between different poles. It has a wall thickness changing portion 410 formed so as to gradually become smaller as it approaches a position passing through.

The magnetic pole core portion 403 may have a configuration that does not have the magnetic pole core central portion 409. That is, the magnetic pole iron core portion 403 may have a configuration having only a pair of wall thickness changing portions 410. Further, in the fourth embodiment, the wall thickness changing portion 410 is provided at the peripheral end portion of the magnetic pole iron core portion 403. However, the magnetic pole iron core portion 403 may have a portion provided on the outer side in the circumferential direction with respect to the wall thickness changing portion 410. In this case, in the portion of the magnetic pole core portion 403 provided outside the wall thickness changing portion 410 in the circumferential direction, the gap length between the rotor core 401 and the teeth 203 on a straight line extending in the radial direction is the wall thickness. It is equal to or less than the gap length between the rotor core 401 and the teeth 203 on a straight line extending in the radial direction in the changing portion 410.

By making the gap length between the different poles 406 and the teeth 203 larger than the gap length between the rotor core 401 and the teeth 203 on a straight line extending in the radial direction without passing between the different poles. , Leakage flux Φx1 and leakage flux Φx2 are reduced. Other configurations are the same as those in the second embodiment.

As described above, according to the rotary electric machine according to the fourth embodiment of the present invention, as in the first embodiment, the decrease in the output torque of the rotary electric machine is suppressed by suppressing the demagnetization in the interpole portion 406. can do. Further, as the leakage flux Φx1 and the leakage flux Φx2 decrease, the effective interlinkage magnetic flux Φt passing through the winding 204 increases. As a result, the output torque of the rotary electric machine can be increased.

Embodiment 5.
FIG. 11 is a cross-sectional view showing a rotary electric machine according to a fifth embodiment of the present invention. FIG. 12 is an enlarged view showing a part E of FIG. In FIG. 11, a cross section perpendicular to the axial direction of the rotary electric machine is shown. In the fourth embodiment, the shape of the permanent magnet 402 is formed into a plate shape. In other words, in the fourth embodiment, each of the surface of the permanent magnet 402 facing outward in the radial direction and the surface facing inward in the radial direction are flat surfaces. On the other hand, in the fifth embodiment, each of the surface of the permanent magnet 402 facing outward in the radial direction and the surface facing inward in the radial direction are curved surfaces in which the peripheral intermediate portion protrudes outward in the radial direction. When viewed in the axial direction, each of the surface of the permanent magnet 402 facing outward in the radial direction and the surface facing inward in the radial direction are arcuate surfaces centered on the center of the rotor 4. Other configurations are the same as those in the fourth embodiment.

As described above, according to the rotary electric machine according to the fifth embodiment of the present invention, the surface of the permanent magnet 402 facing outward in the radial direction is a curved surface. As a result, the surface area of the surface of the permanent magnet 402 facing outward in the radial direction increases. Therefore, the total number of magnetic fluxes passing through the surface of the permanent magnet 402 facing outward in the radial direction increases. As a result, the number of effective interlinkage magnetic fluxes interlinking the winding 204 increases, and the output torque of the rotary electric machine can be improved.

In the fifth embodiment, the configuration in which the surface of the permanent magnet 402 facing inward in the radial direction is a curved surface has been described. FIG. 13 is a cross-sectional view showing a modified example of the rotary electric machine of FIG. FIG. 14 is an enlarged view showing the F portion of FIG. The surface of the permanent magnet 402 facing inward in the radial direction may be a flat surface.

Embodiment 6.
FIG. 15 is a cross-sectional view showing a rotary electric machine according to a sixth embodiment of the present invention. FIG. 16 is an enlarged view showing a portion G of FIG. In FIG. 15, a cross section perpendicular to the axial direction of the rotary electric machine is shown. Let L3 be the distance between one end of the permanent magnet 402 in the circumferential direction and the inner portion in the radial direction and the center of the rotor. The distance between the other end in the circumferential direction of the permanent magnet 402 and the inner portion in the radial direction and the center of the rotor is L4. The distance L3 and the distance L4 are equal to each other. In other words, the distances between both ends of the permanent magnet 402 in the circumferential direction and the inner ends in the radial direction from the center of the rotor 4 are equal to each other.

The radius is the distance between the radial inner portion of the permanent magnet 402 and the center of the rotor 4, and the permanent magnet 402 is inside the cylinder V1 centered on the center of the rotor 4. Some are included. The permanent magnet 402 may be in contact with the side surface of the region of the cylinder V1.

The surface of the permanent magnet 402 facing outward in the radial direction and the surface facing inward in the radial direction are flat surfaces. In other words, the shape of the permanent magnet 402 is a flat plate shape.

When the shape of the permanent magnet is a flat plate shape and the permanent magnet is not included inside the cylinder V1, the radial dimension in the portion of the magnetic pole iron core portion 403 arranged at the circumferential center of the magnetic pole of the rotor 4 is set. It needs to be large. The portion of the magnetic pole core portion 403 arranged at the center of the magnetic pole of the rotor 4 in the circumferential direction is the portion of the magnetic pole core portion 403 arranged on a straight line extending in the radial direction through the rib 405. When the shape of the permanent magnet is a flat plate shape and the permanent magnet is not included inside the cylinder V1, it is perpendicular to the circumferential direction at the portion of the magnetic pole iron core portion 403 arranged at the circumferential center of the magnetic pole of the rotor 4. Cross-sectional area increases. In the sixth embodiment, since a part of the permanent magnet 402 is included inside the cylinder V1, the magnetic pole iron core portion 403 is perpendicular to the circumferential direction as compared with the case where the permanent magnet is not included inside the cylinder V1. The cross-sectional area is reduced. As a result, the magnetic resistance in the circumferential direction at the magnetic pole iron core portion 403 increases. Therefore, among the magnetic fluxes emitted from one of the pair of teeth 203 adjacent to each other in the circumferential direction, the leakage flux Φx3, which is the magnetic flux that returns to the other tooth 203 without interlinking with the permanent magnet 402, is reduced. .. Other configurations are the same as those of the first to fifth embodiments.

As described above, in the rotary electric machine according to the sixth embodiment of the present invention, the distance L3 and the distance L4 are equal to each other. Further, the distance between the radial inner portion of the permanent magnet 402 and the center of the rotor 4 is the radius, and the permanent magnet is inside the cylinder V1 centered on the center of the rotor 4. A portion of 402 is included. Thereby, the leakage flux Φx3 can be reduced. Therefore, the effective interlinkage magnetic flux interlinking with the permanent magnet 402 can be increased. As a result, the output torque of the rotary electric machine can be improved.

Embodiment 7.
FIG. 17 is a cross-sectional view showing a rotary electric machine according to a seventh embodiment of the present invention. FIG. 18 is an enlarged view showing the H portion of FIG. In FIG. 17, a cross section perpendicular to the axial direction of the rotary electric machine is shown. A recess 411 is formed on the surface of the rotor core 401 arranged on a straight line extending in the radial direction through the rib 405 and facing the stator 2.

The recess 411 is formed over the portion of the magnetic pole iron core portion 403 and the rib 405 on the stator 2 side. The recess 411 is arranged at the center of the magnetic pole in the rotor 4 in the circumferential direction. The dimension between the inner peripheral surface of the recess 411 and the permanent magnet 402 adjacent to the recess 411 in the circumferential direction is L5. Let L6 be the radial dimension in the thinnest portion of the radial dimension in the magnetic pole core portion 403. The dimension L5 is equal to or less than the dimension L6.

The shape of the inner peripheral surface of the recess 411 when viewed in the axial direction is U-shaped. The shape of the inner peripheral surface of the recess 411 when viewed in the axial direction may be rectangular, V-shaped, or the like.

The recess 411 in the magnetic pole core portion 403 was formed by forming the recess 411 on the surface facing the stator 2 in the portion of the magnetic pole core portion 403 arranged in a straight line extending in the radial direction through the rib 405. Circumferential magnetoresistance in the portion increases. As a result, the inductance Lq of the interpole portion 406 is reduced. Therefore, the leakage flux Φx4 passing through the magnetic pole iron core portion 403 in the circumferential direction without interlinking with the permanent magnet 402 is reduced.

By reducing the leakage flux Φx4, the total number of magnetic fluxes passing through the stator core 201 is reduced. As a result, an increase in the magnetic resistance of the stator core 201 is suppressed. Therefore, the decrease in the permeance coefficient of the permanent magnet 402 is suppressed. As a result, the torque drop per set current at the time of high load is suppressed.

By reducing the total number of magnetic fluxes passing through the stator core 201, the induced voltage generated in the winding 204 is reduced. As a result, more current flows through the winding 204 even during high-speed rotation. As a result, the maximum output torque of the rotary electric machine during high-speed rotation is increased, and the operating range of the rotary electric machine is expanded. Other configurations are the same as those of the first to sixth embodiments.

As described above, according to the rotary electric machine according to the seventh embodiment of the present invention, the surface facing the stator 2 in the portion of the magnetic pole iron core portion 403 arranged in a straight line extending in the radial direction through the rib 405. Is formed with a recess 411. As a result, the maximum output torque of the rotary electric machine during high-speed rotation can be increased, and the operating range of the rotary electric machine can be expanded.

Embodiment 8.
FIG. 19 is a cross-sectional view showing a rotary electric machine according to the eighth embodiment of the present invention. FIG. 20 is an enlarged view showing a part I of FIG. In FIG. 19, a cross section perpendicular to the axial direction of the rotary electric machine is shown. Magnetically void holes 412 are formed in the portion of the magnetic pole core portion 403 and the portion of the rib 405 arranged on a straight line extending in the radial direction through the rib 405. The hole 412 is arranged at the center of the magnetic pole in the rotor 4 in the circumferential direction. The dimension between the inner peripheral surface of the hole 412 and the permanent magnet 402 adjacent to the hole 412 in the circumferential direction is L7. Let L6 be the radial dimension in the thinnest portion of the radial dimension in the magnetic pole core portion 403. The dimension L7 is equal to or less than the dimension L6.

By forming the holes 412 in the magnetic pole core portion 403 and the rib 405, the magnetic resistance in the circumferential direction in the portion of the magnetic pole core portion 403 where the holes 412 are formed increases. As a result, the inductance Lq of the interpole portion 406 is reduced. Therefore, the leakage flux Φx4 passing through the magnetic pole iron core portion 403 in the circumferential direction without interlinking with the permanent magnet 402 is reduced.

By reducing the leakage flux Φx4, the total number of magnetic fluxes passing through the stator core 201 is reduced. As a result, the increase in the magnetic resistance of the stator core 201 is alleviated. Therefore, the decrease in the permeance coefficient of the permanent magnet 402 is suppressed. As a result, the torque drop per set current at the time of high load is suppressed.

By reducing the total number of magnetic fluxes passing through the stator core 201, the induced voltage generated in the winding 204 is reduced. As a result, more current flows through the winding 204 even during high-speed rotation. As a result, the maximum output torque of the rotary electric machine during high-speed rotation is increased, and the operating range of the rotary electric machine is expanded. Other configurations are the same as those in the seventh embodiment.

As described above, according to the rotary electric machine according to the eighth embodiment of the present invention, the surface facing the stator 2 in the portion of the magnetic pole iron core portion 403 arranged in a straight line extending in the radial direction through the rib 405. Is formed with a recess 411. As a result, the maximum output torque of the rotary electric machine during high-speed rotation can be increased, and the operating range of the rotary electric machine can be expanded. Further, uneven portions are reduced on the outer peripheral surface of the rotor 4. As a result, wind damage and noise generated in the rotary electric machine can be reduced.

1 Front housing, 2 Stator, 3 Rotor shaft, 4 Rotor, 5 1st bearing, 6 End frame, 7 2nd bearing, 8 Support case, 9 Sensor magnet, 10 Magnetic sensor, 101 Housing cylindrical part, 102 1st Bearing holder, 201 stator core, 202 core back, 203 teeth, 204 winding, 204A U-phase winding, 204B V-phase winding, 204C W-phase winding, 401 rotor core, 402 permanent magnet, 403 magnetic pole core Part, 404 Joint iron part, 405 rib, 406 Interpole part, 407 recess, 408 hole, 409 magnetic pole core center, 410 wall thickness change part, 411 recess, 412 hole, 601 end frame base, 602 second bearing holding Part, 603 Axial inner surface.

Claims (11)

A stator core containing a tooth and a stator having a winding provided on the tooth,
It is provided with a rotor core facing the stator and a rotor having a plurality of permanent magnets embedded in the rotor core and arranged in the circumferential direction.
A plurality of magnetic poles different from each other are arranged side by side in the circumferential direction on the portion of the permanent magnet on the stator side.
The rotor core is
Ribs sandwiched between the pair of permanent magnets adjacent to each other in the circumferential direction,
It has a magnetic pole core portion provided on the stator side of the permanent magnet and connected to the rib.
A gap is formed between the permanent magnet and the rib in the circumferential direction.
The surface facing the circumferential direction in the gap between the permanent magnet and the rib is composed of the surface of the permanent magnet and the surface of the rib.
The same magnetic poles are arranged at the portions on the stator side of each of the pair of permanent magnets sandwiching the rib and adjacent to each other in the circumferential direction.
The magnetic void length between the permanent magnet and the tooth on a straight line extending in the radial direction through different poles between the parts on the stator side of the permanent magnet and having different magnetic poles from each other. Is a rotating electric machine having a length larger than the magnetic gap length between the rotor core and the teeth on a straight line extending radially through the rib. A stator core containing a tooth and a stator having a winding provided on the tooth,
It is provided with a rotor core facing the stator and a rotor having a plurality of permanent magnets embedded in the rotor core and arranged in the circumferential direction.
A plurality of magnetic poles different from each other are arranged side by side in the circumferential direction on the portion of the permanent magnet on the stator side.
The rotor core is
Ribs sandwiched between the pair of permanent magnets adjacent to each other in the circumferential direction,
It has a magnetic pole core portion provided on the stator side of the permanent magnet and connected to the rib.
The same magnetic poles are arranged at the portions on the stator side of each of the pair of permanent magnets sandwiching the rib and adjacent to each other in the circumferential direction.
The magnetic void length between the permanent magnet and the tooth on a straight line extending in the radial direction through different poles between the parts on the stator side of the permanent magnet and having different magnetic poles from each other. Is greater than the magnetic void length between the rotor core and the teeth on a straight line extending radially through the ribs.
A magnetically hollow hole is formed in the portion of the magnetic pole iron core portion arranged on a straight line extending in the radial direction through the different poles.
The surface of the magnetic pole core portion that is arranged on a straight line that passes between the different poles and extends in the radial direction and that faces the radial outer side of the other magnetic pole core portion is the same circle. Rotating electric machine placed on the top. The rotary electric machine according to claim 1, wherein the magnetic pole iron core portion is arranged so as to be displaced in the circumferential direction from a straight line extending in the radial direction through the different poles. The rotary electric machine according to claim 1, wherein a magnetically hollow hole is formed in a portion of the magnetic pole iron core portion arranged on a straight line extending in the radial direction through the different poles. The magnetic pole core portion passes through the rib from a position where the gap length between the rotor core and the tooth on a linearly extending radial direction is such that the position of the straight line extending in the radial direction passes between the different poles. The rotary electric machine according to claim 1, which has a wall thickness changing portion formed so as to gradually become smaller as it approaches a position. The distances between both ends of the permanent magnet in the circumferential direction and the inner ends in the radial direction and the center of the rotor are equal to each other.
The radius is the distance between the radial inner end of the permanent magnet and the center of the rotor, and one of the permanent magnets is within the region of the cylinder centered on the center of the rotor. The rotary electric machine according to any one of claims 1 to 5, wherein the part is included. Any of claims 1 to 6, wherein a recess is formed on the surface of the portion of the magnetic pole iron core portion arranged on a straight line extending radially outward through the rib and facing the stator. The rotary electric machine described in item 1. According to any one of claims 1 to 6, a magnetically hollow hole is formed in a portion of the magnetic pole iron core portion arranged on a straight line extending radially outward through the rib. The rotating electric machine described. A rotor core and a rotor having a plurality of permanent magnets embedded at intervals in the circumferential direction in the radial outer portion of the rotor core.
A stator having a plurality of teeth, each of which is provided with a winding, and arranged so as to face the rotor in the radial direction.
With
The rotor core has a pair of ribs that sandwich the permanent magnet in the circumferential direction, and a magnetic pole core portion that is provided on the stator side of the permanent magnet and is connected to the ribs.
The magnetic pole iron core portion is a portion of the permanent magnet arranged on a straight line extending in the radial direction through different poles, which is a portion of the permanent magnet on the stator side and between portions having different magnetic poles. It is not arranged in the radial direction outside the interpolar part, which is
The two cores of the magnetic poles included in the magnetic circuit that enters the other magnetic pole from one magnetic pole in the same permanent magnet are arranged apart from each other in the circumferential direction.
The magnetic gap length between the permanent magnet and the tooth on the straight line extending in the radial direction through the different poles is the same as that of the rotor core on the straight line extending in the radial direction through the rib. A rotating electric machine that is larger than the gap length between the teeth. The surface of the permanent magnet facing outward in the radial direction is a flat surface or an arcuate surface whose circumferential intermediate portion projects outward in the radial direction.
The rotary electric machine according to claim 9, wherein the magnetic pole iron core portion is provided outside the permanent magnet in the radial direction. The rotary electric machine according to claim 9 or 10, wherein the circumferential end portion of the magnetic pole iron core portion has a smaller radial dimension toward the outer side in the circumferential direction.

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