JP7254215B2 - Rotating electric machine and elevator hoist - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating electric machine provided with a stator having teeth, and an elevator hoist provided with the rotating electric machine.

2. Description of the Related Art Conventionally, a rotary electric machine is known in which torque ripple is reduced by providing auxiliary grooves at the tips of all teeth in a stator (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2005-094901

However, in the conventional rotary electric machine disclosed in Patent Literature 1, the amount of magnetic flux passing through all the teeth is reduced because the auxiliary grooves are provided at the tips of all the teeth. For this reason, there has been a concern that the torque output will decrease in the conventional rotating electric machine.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotating electric machine and an elevator hoist capable of suppressing a decrease in torque output while reducing torque ripple. With the goal.

A rotating electric machine according to the present invention includes a rotor that rotates about an axis, and a stator that faces the rotor with a gap in the radial direction of the rotor. The rotor includes a rotor core, The rotor core has a plurality of magnetic poles arranged in a circumferential direction of the rotor, and the stator has a stator core and a plurality of windings provided on the stator core. , the stator core has a back yoke and a plurality of teeth projecting from the back yoke toward the rotor, and the plurality of teeth are spaced apart from each other in the circumferential direction of the stator. , Each tooth has a tip facing the rotor, the winding is wound around the tooth by concentrated winding, and the three teeth arranged continuously in the circumferential direction of the stator form a set of teeth. The same phase winding is wound on each of the three teeth that make up one tooth group. A low magnetic permeability portion is provided at the tip of each tooth, and the magnetic permeability of the low magnetic permeability portion is lower than the magnetic permeability of the stator core.

According to the rotary electric machine and the elevator hoisting machine according to the present invention, it is possible to suppress a decrease in torque output while reducing torque ripple.

1 is a cross-sectional view showing a rotating electric machine according to Embodiment 1; FIG. FIG. 2 is a developed view showing a developed state of a portion including a set of U-phase teeth in the stator core of FIG. 1 ; 2 is a cross-sectional view showing a rotating electrical machine of Comparative Example 1; FIG. FIG. 8 is a cross-sectional view showing a rotating electric machine of Comparative Example 2; 4 is a graph showing the magnitude of torque output in each of Comparative Example 1, Comparative Example 2, and Embodiment 1. FIG. 7 is a graph showing torque output waveforms in Comparative Example 1, Comparative Example 2, and Embodiment 1, respectively. 7 is a graph showing the magnitude of torque ripple in each of Comparative Example 1, Comparative Example 2, and Embodiment 1. FIG. 4 is a developed view showing another example of a portion including a U-phase tooth set in the rotating electric machine of the first embodiment; FIG. 4 is a developed view showing another example of a portion including a U-phase tooth set in the rotating electric machine of the first embodiment; FIG. FIG. 6 is a cross-sectional view showing a rotating electrical machine according to Embodiment 2; 9 is a graph showing the magnitude of torque output in each of the rotary electric machine of Comparative Example 1, the rotary electric machine during forward rotation of Embodiment 2, and the rotary electric machine during reverse rotation of Embodiment 2. FIG. 9 is a graph showing torque output waveforms in each of the rotary electric machine of Comparative Example 1, the rotary electric machine of the second embodiment during forward rotation, and the rotary electric machine of the second embodiment during reverse rotation; 9 is a graph showing the magnitude of torque ripple in each of the rotating electric machine of Comparative Example 1, the rotating electric machine of Embodiment 2 during forward rotation, and the rotating electric machine of Embodiment 2 during reverse rotation. FIG. 11 is a cross-sectional view showing a rotating electric machine according to Embodiment 3; FIG. 11 is a cross-sectional view showing a rotating electric machine according to Embodiment 4; FIG. 11 is a cross-sectional view showing a rotating electrical machine according to Embodiment 5; FIG. 14 is an exploded perspective view showing a stator core of a rotating electric machine according to Embodiment 6; FIG. 21 is an exploded perspective view showing another example of the stator core of the rotary electric machine according to Embodiment 6; FIG. 11 is a longitudinal sectional view showing an elevator hoist according to Embodiment 7;

Embodiments will be described below with reference to the drawings.
Embodiment 1.
FIG. 1 is a cross-sectional view showing a rotating electric machine according to Embodiment 1. FIG. A rotating electric machine 1 includes a rotor 2 and a stator 6 . The rotor 2 and stator 6 have a common axis as a main axis. The rotor 2 is fixed to a rotating shaft 3 rotatably supported by a housing (not shown). The rotor 2 and stator 6 are arranged coaxially with the rotating shaft 3 . The rotor 2 rotates integrally with the rotating shaft 3 around the main axis. Here, the direction along the radius of the rotor 2 is defined as the radial direction, and the direction along the rotation direction of the rotor 2 is defined as the circumferential direction.

The stator 6 faces the rotor 2 with a gap in the radial direction of the rotor 2 . A stator 6 surrounds the rotor 2 . The inner peripheral portion of the stator 6 faces the outer peripheral portion of the rotor 2 with a gap therebetween. The rotor 2 and stator 6 are contained within a housing.

The rotor 2 has a rotor core 4 , which is a magnetic body fixed to the rotating shaft 3 , and a plurality of magnetic poles 5 provided on the rotor core 4 .

The rotor core 4 is a columnar laminate formed by laminating a plurality of thin plates in the direction along the main axis. Magnetic steel sheets, for example, are used as the plurality of thin plates that constitute the rotor core 4 . The rotor core 4 is provided with an axial through hole along the main axis. The rotating shaft 3 is inserted into the shaft through hole of the rotor core 4 .

A plurality of magnetic poles 5 are fixed to the outer peripheral surface of the rotor core 4 . A plurality of magnetic poles 5 are arranged in the circumferential direction of the rotor core 4 . The plurality of magnetic poles 5 are arranged at equal pitches in the circumferential direction of the rotor core 4 . Each magnetic pole 5 is composed of a permanent magnet. A plurality of magnetic poles 5 are provided on the outer peripheral surface of the rotor core 4 so that the polarities facing the stator 6 alternate in the circumferential direction of the rotor 2 . Therefore, of the two magnetic poles 5 adjacent to each other in the circumferential direction of the rotor 2, the N pole of one magnetic pole 5 faces the stator 6, and the S pole of the other magnetic pole 5 faces the stator 6. . In this example, the rotor 2 has ten magnetic poles 5 .

The stator 6 has a stator core 7 which is a magnetic material and a plurality of windings 10 provided on the stator core 7 .

The stator core 7 is a laminate formed by laminating a plurality of thin plates in the direction along the main axis. Electromagnetic steel sheets, for example, are used as the plurality of thin plates that constitute the stator core 7 . The stator core 7 also has an annular back yoke 9 and a plurality of teeth 8 projecting radially inward from the back yoke 9 toward the rotor 2 .

A plurality of teeth 8 are arranged at intervals in the circumferential direction of stator 6 . A plurality of teeth 8 are arranged at equal pitches in the circumferential direction of the stator 6 . In this example, nine teeth 8 are included in stator core 7 . Each tooth 8 has a tip portion 83 facing the rotor 2 with a gap therebetween. Spaces formed between a plurality of teeth 8 are provided as slots in the stator core 7 .

A plurality of windings 10 are wound around each tooth 8 one by one by concentrated winding. Thereby, a portion of the winding 10 is accommodated in each slot. In this example nine windings 10 are included in the stator 6 .

The multiple windings 10 are connected to an AC power supply via power lines (not shown). Thereby, three-phase AC power is supplied to the plurality of windings 10 . The three-phase AC power includes U-phase, V-phase, and W-phase power whose electrical phases are different from each other by 120°. A rotating magnetic field is generated in the stator 6 by supplying three-phase AC power to a plurality of windings 10 . Torque is generated in the rotor 2 by magnetic interaction between the rotating magnetic field generated in the stator 6 and the plurality of magnetic poles 5 . Thereby, the rotor 2 rotates with respect to the stator 6 integrally with the rotating shaft 3 .

In the stator core 7 , three teeth 8 continuous in the circumferential direction of the stator 6 form a tooth group 81 . In this example, since nine teeth 8 are included in the stator core 7, a U-phase tooth group 81, a V-phase tooth group 81, and a W-phase tooth group 81 are three tooth groups 81 in the stator. Located in core 7.

Electric power of the same phase is supplied to each winding 10 wound around each of the three teeth 8 forming one tooth group 81 . That is, the windings 10 of the same phase are wound around each of the three teeth 8 forming one tooth group 81 .

As a result, the winding 10 wound around each tooth 8 constituting the U-phase tooth group 81 of the three tooth groups 81 is a U-phase winding to which U-phase power is supplied. . The winding 10 wound around each tooth 8 constituting the V-phase tooth group 81 is a V-phase winding to which V-phase power is supplied. The winding 10 wound around each tooth 8 constituting the W-phase tooth group 81 is a W-phase winding to which W-phase power is supplied.

In each tooth group 81, the winding direction of the windings 10 wound around the two outer teeth 8 is the forward direction, and the winding direction of the windings 10 wound around the center teeth 8 is the opposite direction. ing.

In the present embodiment, in order to clearly distinguish the winding direction of the winding 10, the U-phase winding 10 is indicated as "U phase" when the winding direction is forward, and the winding direction is reverse. If it is the direction, it is represented as "Ui phase". Similarly, the V-phase winding 10 is represented as "V-phase" when the winding direction is forward, and is represented as "Vi-phase" when the winding direction is reverse. The W-phase winding 10 is indicated as "W-phase" when the winding direction is forward, and is indicated as "Wi-phase" when the winding direction is reverse.

A low magnetic permeability portion 82 is provided at the tip portion 83 of each of the two outer teeth 8 among the three teeth 8 forming the tooth group 81 . The low magnetic permeability portion 82 is not provided at the tip portion 83 of the central tooth 8 among the three teeth 8 forming the tooth group 81 . That is, in each tooth group 81 , the low magnetic permeability portions 82 are provided at the tip portions 83 of the two outer teeth 8 , avoiding the center tooth 8 of the three teeth 8 . The magnetic permeability of the low magnetic permeability portion 82 is lower than that of the stator core 7 .

Grooves 821 are provided in the tip portions 83 of the two outer teeth 8 in each tooth group 81 . A space formed by the groove 821 serves as the low magnetic permeability portion 82 .

The grooves 821 are opened from the tip portions 83 of the teeth 8 toward the rotor 2 side. Also, the grooves 821 are arranged in a direction along the main axis. The grooves 821 are arranged over the entire range of the stator core 7 in the direction along the main axis. In each tooth group 81, the two outer teeth 8 are provided with one groove 821 each. In the cross section of the tooth 8 on the plane perpendicular to the main axis, the low magnetic permeability portion 82 formed by the grooves 821 has a rectangular shape.

FIG. 2 is a developed view showing a state in which a portion including the U-phase tooth set 81 in the stator core 7 of FIG. 1 is developed. The back yoke 9 has a plurality of back yoke members 91 arranged in an annular shape. In this example, the back yoke 9 includes nine back yoke members 91 . Each back yoke member 91 is arranged along the circumferential direction of the stator 6 along the width direction of the back yoke member 91 .

One tooth 8 is provided on each of the plurality of back yoke members 91 . The teeth 8 protrude from the widthwise central portion of the back yoke member 91 .

Abutting surfaces 50 are formed at both ends of each back yoke member 91 in the width direction. In the annular state in which the plurality of back yoke members 91 are arranged in an annular shape, the abutment surfaces 50 of two adjacent back yoke members 91 are in contact with each other. Two back yoke members 91 adjacent to each other are connected via a connecting portion 60 at a corner portion opposite to the teeth 8 . The state of the stator core 7 changes from the annular state to the deployed state as each back yoke member 91 rotates around the connecting portion 60 . In the unfolded state of the stator core 7, a plurality of back yoke members 91 are arranged in a line with the abutment surfaces 50 separated from each other.

Each tooth 8 has a centerline along the radial direction of the stator 6 . In the cross section of the stator core 7 on the plane orthogonal to the main axis, the straight line passing through the main axis and the center position of the teeth 8 in the width direction is the center line of the teeth 8 . When the state of the stator core 7 is the deployed state, each tooth group 81 has a center line CL of the center tooth 8, a center line CL1 of one outer tooth 8, and a center line of the other outer tooth 8. CL2 are parallel to each other. Further, when the state of the stator core 7 is the deployed state, the distance between the center line CL of the center tooth 8 and the center line CL1 of one of the outer teeth 8 and the distance between the center line CL of the center tooth 8 and the other tooth 8 are The distance from the center line CL2 of the outer tooth 8 is equal to the distance τ0.

Each of the low magnetic permeability portions 82 formed by the grooves 821 has a center line parallel to the center lines CL1 and CL2 of the teeth 8 on which the low magnetic permeability portions 82 are provided. Here, of the two low magnetic permeability portions 82 in each tooth group 81, the center line of the low magnetic permeability portion 82 provided on the tooth 8 having the center line CL1 is defined as CL11, and the center line of the low magnetic permeability portion 82 provided on the tooth 8 having the center line CL2 is defined as CL11. The center line of the low magnetic permeability portion 82 thus formed is defined as CL21. When the stator core 7 is in the deployed state, in each tooth group 81, the distance from the center line CL11 to the center line CL and the distance from the center line CL21 to the center line CL are the same distance τ. ing. Further, when the state of the stator core 7 is the deployed state, the relationship τ>τ0 is established.

Therefore, in each tooth group 81, the low magnetic permeability portions 82 provided on the teeth 8 having the center line CL1 are arranged at positions farther from the center line CL than the center line CL1. Further, in each tooth group 81, the low magnetic permeability portions 82 provided on the teeth 8 having the center line CL2 are arranged at positions farther from the center line CL than the center line CL2. That is, the low magnetic permeability portion 82 is arranged at a position farther from the center line CL of the central tooth 8 in the circumferential direction of the stator 6 than the center lines CL1 and CL2 of the teeth 8 on which the low magnetic permeability portion 82 is provided. ing. Also, the low magnetic permeability portions 82 provided on the two outer teeth 8 are provided at geometrically symmetrical positions with respect to the center line CL. The low magnetic permeability portions 82 provided on the two outer teeth 8 have the same shape.

Next, rotating electrical machines of Comparative Examples 1 and 2 for comparison with the rotating electrical machine 1 according to Embodiment 1 will be described. FIG. 3 is a cross-sectional view showing a rotating electrical machine of Comparative Example 1. FIG. In the rotary electric machine 200 of Comparative Example 1, the grooves 821 are not provided in the tip portions 83 of all the teeth 8 . Other configurations of Comparative Example 1 are the same as those of the first embodiment.

FIG. 4 is a cross-sectional view showing a rotating electrical machine of Comparative Example 2. FIG. In the rotating electric machine 300 of Comparative Example 2, the low magnetic permeability portions 82 are provided at the tip portions 83 of all the teeth 8 included in the stator core 7 . In Comparative Example 2, spaces formed by grooves 821 similar to those in the first embodiment are provided in each tooth 8 as low magnetic permeability portions 82 . Further, in Comparative Example 2, two low magnetic permeability portions 82 are provided on each tooth 8 . Other configurations of Comparative Example 2 are the same as those of Comparative Example 1. FIG.

FIG. 5 is a graph showing magnitudes of torque outputs in Comparative Example 1, Comparative Example 2, and Embodiment 1, respectively. FIG. 5 shows the magnitude of the torque output of the rotary electric machine when the rotor 2 is rotated at the same rotational speed in Comparative Example 1, Comparative Example 2, and Embodiment 1. As shown in FIG. In FIG. 5, the magnitude of the torque output in Comparative Example 1 is set as a reference value of "100", and the magnitude of the torque output in each of Comparative Example 2 and Embodiment 1 is standardized according to the set reference value of Comparative Example 1. is becoming

FIG. 6 is a graph showing torque output waveforms in Comparative Example 1, Comparative Example 2, and Embodiment 1, respectively. FIG. 6 shows torque output waveforms of the rotary electric machine when the plurality of windings 10 are excited with the same current magnitude in Comparative Example 1, Comparative Example 2, and Embodiment 1. FIG. In FIG. 6, the waveform of the torque output in Comparative Example 1 is indicated by a solid line, the waveform of the torque output in Comparative Example 2 is indicated by a broken line, and the waveform of the torque output in Embodiment 1 is indicated by a dashed line. Torque ripple is calculated from the difference between the maximum value and the minimum value of the torque output waveform.

FIG. 7 is a graph showing magnitudes of torque ripples in Comparative Example 1, Comparative Example 2, and Embodiment 1, respectively. FIG. 7 shows the sixth-order component with respect to an electrical angle of 360° among the torque ripple components calculated from the waveform of the torque output in FIG. In FIG. 7, the magnitude of the torque ripple in Comparative Example 1 is set as a reference value of "100", and the magnitude of the torque ripple in each of Comparative Example 2 and Embodiment 1 is standardized by the set reference value of Comparative Example 1. is becoming

It can be seen from FIG. 5 that the torque output of the rotating electrical machine 1 of Embodiment 1 is greater than the torque output of the rotating electrical machine 300 of Comparative Example 2. FIG. This is because the center tooth 8 of each tooth group 81 is not provided with the low magnetic permeability portion 82, so that the increase in magnetic resistance in the center tooth 8 is suppressed, and the amount of effective magnetic flux passing through each tooth 8 is reduced. This is because is suppressed. 6 and 7 show that the torque ripple of rotating electrical machine 1 of the first embodiment is smaller than the torque ripple of rotating electrical machine 200 of comparative example 1. FIG. This is considered to be due to the fact that the two outer teeth 8 in each tooth group 81 are provided with the low magnetic permeability portions 82 . Further, from FIG. 7, it can be seen that the magnitude of the torque ripple in the rotating electrical machine 1 of Embodiment 1 is approximately the same as the magnitude of the torque ripple in the rotating electrical machine 300 of Comparative Example 2. FIG. Therefore, it was confirmed that, in the rotating electric machine 1 of Embodiment 1, it was possible to reduce the torque ripple and suppress the decrease in the torque output.

In the rotary electric machine 1 according to Embodiment 1, in each tooth group 81 , the low magnetic permeability portions 82 are provided at the tip portions 83 of the two outer teeth 8 avoiding the center tooth 8 . Therefore, it is possible to suppress a decrease in torque output while reducing torque ripple.

In each tooth group 81, the low magnetic permeability portions 82 provided on the two outer teeth 8 are geometrically symmetrical with respect to the center line CL of the central tooth 8 in the cross section perpendicular to the main axis. It is set at a position where Therefore, the waveform of the torque output of the rotary electric machine 1 can be the same regardless of whether the rotation direction of the rotor 2 is clockwise or counterclockwise. Therefore, it is possible to prevent a situation in which noise and vibration of the rotating electric machine 1 are generated differently depending on the rotation direction of the rotor 2 .

In addition, the low magnetic permeability portions 82 are arranged at positions farther from the center lines CL of the central teeth 8 in the circumferential direction of the stator 6 than the center lines CL1 and CL2 of the teeth 8 on which the low magnetic permeability portions 82 are provided. ing. Therefore, it is possible to further reliably suppress a decrease in torque output while reducing torque ripple.

Also, the low magnetic permeability portion 82 is a space portion formed by a groove 821 provided in the tip portion 83 of the tooth 8 . Therefore, the low magnetic permeability portions 82 can be easily provided at the tip portions 83 of the teeth 8 .

Moreover, the cross-sectional shape of each low magnetic permeability part 82 is the same shape. Therefore, it is possible to suppress the occurrence of the secondary component of the torque ripple with respect to the electrical angle of 360°. However, if the generation of the secondary component of the torque ripple is within the permissible range, the cross-sectional shape of each low magnetic permeability portion 82 may be different from each other.

In addition, windings 10 of the same phase are wound around three teeth 8 continuously arranged in the circumferential direction of the stator 6 . Therefore, the windings 10 of the same phase can be continuously wound around the three teeth 8 . Thereby, the time required for the winding process of winding the winding 10 around each tooth 8 can be shortened, and the manufacturing time of the rotary electric machine 1 can be shortened.

In Embodiment 1, the low magnetic permeability portions 82 provided on the teeth 8 having the center lines CL1 and CL2 are located in the center of the teeth 8 in the circumferential direction of the stator 6 relative to the center lines CL1 and CL2 of the teeth 8. It is arranged at a position far from the center line CL. However, the low magnetic permeability portions 82 provided in the teeth 8 having the center line CL1 may be arranged at the same position as the center line CL1, or may be arranged at a position closer to the center line CL than the center line CL1. may Further, the low magnetic permeability portion 82 provided in the tooth 8 having the center line CL2 may be arranged at the same position as the center line CL2, or may be arranged at a position closer to the center line CL than the center line CL2. may That is, the relationship τ=τ0 may be established, or the relationship τ<τ0 may be established. Even in this way, it is possible to suppress a decrease in the torque output of the rotating electrical machine 1 while reducing the torque ripple of the rotating electrical machine 1 .

Further, in Embodiment 1, the cross-sectional shape of the low magnetic permeability portion 82 formed by the grooves 821 is rectangular. However, the cross-sectional shape of the low magnetic permeability portion 82 is not limited to a rectangular shape. For example, as shown in FIG. 8, the cross-sectional shape of the low magnetic permeability portion 82 formed by the grooves 821 may be semicircular. Furthermore, as shown in FIG. 9, the cross-sectional shape of the low magnetic permeability portion 82 formed by the grooves 821 may be triangular.

Embodiment 2
FIG. 10 is a cross-sectional view showing rotating electric machine 1 according to the second embodiment. In the second embodiment, of the three teeth 8 constituting the tooth set 81, the low magnetic permeability portion 82 is provided at the tip portion 83 of the other outer tooth 8 while avoiding the center and one outer tooth 8. It is That is, in each tooth group 81, among the three teeth 8, the central and one outer teeth 8 are not provided with the low magnetic permeability portion 82, and only the tip portion 83 of the other outer tooth 8 is provided with the low magnetic permeability portion 82. A low magnetic permeability portion 82 is provided. The low magnetic permeability portion 82 is a space formed by grooves 821 similar to those of the first embodiment. Other configurations in the second embodiment are similar to those in the first embodiment.

In FIG. 10 , the rotating direction of the rotor 2 is counterclockwise when the rotating electrical machine 1 rotates forward, and the rotating direction of the rotor 2 is clockwise when the rotating electrical machine 1 rotates in the reverse direction. Therefore, in each tooth group 81 , among the three teeth 8 , the low magnetic permeability portion 82 is provided on the tooth 8 on the rear side in the rotation direction of the rotor 2 when the rotating electric machine 1 rotates forward.

11 is a graph showing the magnitude of the torque output in each of the rotating electrical machine of Comparative Example 1, the rotating electrical machine of the second embodiment during forward rotation, and the rotating electrical machine of the second embodiment during reverse rotation, which are shown in FIG. be. FIG. 11 shows the magnitude of the torque output of each rotating electrical machine when the rotor 2 is rotated at the same rotational speed. In FIG. 11, the magnitude of torque output in Comparative Example 1 is set as a reference value of "100", and the set reference value of Comparative Example 1 determines the magnitude of torque output during forward rotation and reverse rotation of Embodiment 2. standardized.

FIG. 12 is a graph showing torque output waveforms in each of the rotating electrical machine of Comparative Example 1, the rotating electrical machine of the second embodiment during forward rotation, and the rotating electrical machine of the second embodiment during reverse rotation. FIG. 12 shows the torque output of the rotary electric machine when the plurality of windings 10 are excited by the same current magnitude during forward rotation in Comparative Example 1 and Embodiment 2, and during reverse rotation in Embodiment 2. Waveforms are shown. In FIG. 12, the waveform of the torque output in Comparative Example 1 is indicated by a solid line, the waveform of the torque output during forward rotation in the second embodiment is indicated by a dashed line, and the waveform of the torque output during reverse rotation in the second embodiment is indicated by a broken line. indicated by the dashed-dotted line. Torque ripple is calculated from the difference between the maximum value and the minimum value of the torque output waveform.

FIG. 13 is a graph showing the magnitude of torque ripple in each of the rotary electric machine of Comparative Example 1, the rotary electric machine of the second embodiment during forward rotation, and the rotary electric machine of the second embodiment during reverse rotation. FIG. 13 shows the sixth-order component with respect to an electrical angle of 360° among the torque ripple components calculated from the waveform of the torque output in FIG. In FIG. 13 , the magnitude of the torque ripple in Comparative Example 1 is set as a reference value of “100”, and the magnitude of the torque ripple during forward rotation and reverse rotation of Embodiment 2 is set according to the set reference value of Comparative Example 1. standardized.

From FIG. 11, it can be seen that the magnitude of the torque output of the rotary electric machine 1 according to Embodiment 2 is approximately the same both during normal rotation and during reverse rotation. Further, the magnitude of the torque output of the rotating electrical machine 1 according to the second embodiment is smaller than the magnitude of the torque output of the rotating electrical machine 200 of the first comparative example. However, comparing FIGS. 11 and 5, the magnitude of the torque output of the rotating electrical machine 1 according to Embodiment 2 is greater than the magnitude of the torque output of the rotating electrical machine 300 of Comparative Example 2 shown in FIG. I understand. This is because only one tooth 8 out of the three teeth 8 in each tooth group 81 is provided with the low magnetic permeability portion 82, so that the reduction in the amount of effective magnetic flux passing through each tooth 8 is less than that of the rotation of Comparative Example 2. This is because the decrease in the amount of effective magnetic flux in the electric machine 300 is suppressed.

From FIGS. 12 and 13, it can be seen that the torque ripple during forward rotation and reverse rotation of the rotating electrical machine 1 of the second embodiment is smaller than the torque ripple of the rotating electrical machine 200 of the first comparative example. In particular, the magnitude of the torque ripple during forward rotation in the second embodiment is significantly smaller than that in the first comparative example. On the other hand, when looking at FIGS. 13 and 7, the magnitude of the torque ripple during reverse rotation in the second embodiment is larger than the torque ripple in the second comparative example. Therefore, by providing the low magnetic permeability portion 82 only on the tooth 8 located on the rear side in the rotation direction of the rotor 2 among the three teeth 8 constituting the tooth group 81, the torque ripple can be effectively reduced. while suppressing a decrease in torque output. Therefore, when the rotary electric machine 1 is used with its rotation direction restricted to a certain direction, it is effective to provide the low magnetic permeability portions 82 on the teeth 8 on the rear side in the rotation direction of the rotor 2 .

As described above, in the rotating electric machine 1 according to Embodiment 2, of the three teeth 8 forming each tooth group 81, the tip of the tooth 8 on the other outside is avoided while avoiding the teeth 8 on the center and one outside. A low magnetic permeability portion 82 is provided in the portion 83 . Therefore, by restricting the rotation direction of the rotor 2 to a certain direction, it is possible to suppress a decrease in torque output while reducing torque ripple. That is, by restricting the rotation direction of the rotor 2 to a fixed direction, only the teeth 8 located on the rear side in the rotation direction of the rotor 2 among the three teeth 8 forming the teeth set 81 have a low magnetic permeability portion. 82 may be provided. Thereby, the low magnetic permeability portion 82 can be provided on the tooth 8 that effectively reduces the torque ripple in the rotation direction of the rotor 2 among the three teeth 8 that constitute the tooth group 81 . Moreover, it is possible to further suppress the decrease in the amount of effective magnetic flux that contributes to the torque output. Therefore, it is possible to effectively suppress a decrease in torque output while reducing torque ripple.

In addition, the low magnetic permeability portion 82 may be arranged at the same position as the center line of the tooth 8 on which the low magnetic permeability portion 82 is provided, or the center line of the tooth 8 may may be placed at a position close to Even in this way, it is possible to suppress a decrease in the torque output of the rotating electrical machine 1 while reducing the torque ripple of the rotating electrical machine 1 .

Embodiment 3.
FIG. 14 is a cross-sectional view showing rotating electric machine 1 according to the third embodiment. In each tooth group 81 , a through hole 824 is provided in the tip end portion 83 of each of the two outer teeth 8 avoiding the center tooth 8 among the three teeth 8 in the direction along the main axis. In each tooth group 81 , the space formed by the through hole 824 serves as the low magnetic permeability portion 82 . The central tooth 8 is not provided with the low magnetic permeability portion 82 .

The cross-sectional shape of the through hole 824 is circular. The positions of the through holes 824 in the circumferential direction of the stator 6 are the same as the positions of the grooves 821 in the first embodiment. Therefore, the low magnetic permeability portion 82 is arranged at a position farther from the center line CL of the central tooth 8 in the circumferential direction of the stator 6 than the center lines CL1 and CL2 of the teeth 8 on which the low magnetic permeability portion 82 is provided. ing. Further, in each tooth group 81, the low magnetic permeability portions 82 respectively provided on the two outer teeth 8 are provided at positions that are geometrically symmetrical with respect to the center line CL of the center tooth 8. . Other configurations in the fourth embodiment are similar to those in the first embodiment.

By providing the through holes 824 in the tip portions 83 of the teeth 8 in this manner, the spaces formed by the through holes 824 can be provided in the tip portions 83 of the teeth 8 as the low magnetic permeability portions 82 . Accordingly, the low magnetic permeability portions 82 can be easily provided at the tip portions 83 of the teeth 8 .

In addition, in Embodiment 3, the cross-sectional shape of the low magnetic permeability portion 82 formed by the through hole 824 is circular. However, the cross-sectional shape of the low magnetic permeability portion 82 formed by the through hole 824 is not limited to this. The cross-sectional shape of the low magnetic permeability portion 82 formed by the through hole 824 may be rectangular, triangular, or the like.

Embodiment 4.
FIG. 15 is a cross-sectional view showing rotating electric machine 1 according to the fourth embodiment. In each tooth group 81, a space formed by a groove 821 similar to that of the first embodiment is provided at the tip end portion 83 of each of the two outer teeth 8 avoiding the central tooth 8 of the three teeth 8. It is A space formed by the groove 821 is filled with a filling material 825 as the low magnetic permeability portion 82 . That is, the low magnetic permeability part 82 is a filling material 825 filled in the space formed by the groove 821 . A non-magnetic resin or the like is used as the filler 825 . The central tooth 8 is not provided with the low magnetic permeability portion 82 . Other configurations in the fourth embodiment are similar to those in the first embodiment.

In the rotary electric machine 1 according to the fourth embodiment, the spaces provided at the tip portions 83 of the teeth 8 are filled with the filling material 825 as the low magnetic permeability portions 82 . Therefore, the space formed by the groove 821 can be filled with the filler 825, and the filler 825 can be connected in the direction along the main axis. Thereby, the rigidity of the teeth 8 can be increased. Therefore, the resonance frequency of the rotating electric machine can be increased, and the occurrence of mechanical noise and vibration can be suppressed.

Note that the filler 825 is not limited to resin. For example, a metal having a magnetic permeability lower than that of the stator core 7 may be used as the filler 825 .

Further, in the fourth embodiment, the space provided at the tip portion 83 of the tooth 8 in the first embodiment is filled with the filler 825 . However, in Embodiments 2 and 3, the filling material 825 may be filled in the spaces provided at the tip portions 83 of the teeth 8 .

Embodiment 5.
16 is a cross-sectional view showing a rotating electric machine according to Embodiment 5. FIG. In each tooth group 81 , of the three teeth 8 , crimped portions 826 are provided as low magnetic permeability portions 82 at the tip portions 83 of the two outer teeth 8 avoiding the center tooth 8 . The crimped portion 826 is a portion that joins a plurality of laminated thin plates in the stator core 7 . The crimped portion 826 provided at the tip portion 83 of the tooth 8 is arranged parallel to the main axis.

The stator core 7 is produced by bonding a plurality of laminated raw material plates to each other. The plurality of raw material plates are joined together by being partially deformed by mechanical processing. A portion of the raw material sheet that has been deformed by mechanical processing is formed in the stator core 7 as a caulking portion 826 that joins a plurality of raw material sheets together. On the other hand, the portion of the raw material plate other than the caulked portion 826 becomes a part of the stator core 7 as a thin plate. The caulked portion 826 is magnetically deteriorated more than the stator core 7 due to deformation of the raw material plate due to mechanical processing. Therefore, the magnetic permeability of the caulked portion 826 is lower than the magnetic permeability of the stator core 7 .

The crimped portion 826 has a circular shape. The position of the crimped portion 826 is the same as the position of the through hole 824 in the second embodiment. Other configurations in the fifth embodiment are similar to those in the first embodiment.

In the rotating electric machine 1 according to Embodiment 5, the crimped portions 826 provided at the tip portions 83 of the teeth 8 are the low magnetic permeability portions 82 . Therefore, only by forming crimped portions on the stacked raw material plates by mechanical processing, the plurality of raw material plates can be joined together, and the low magnetic permeability portions 82 are provided at the tip portions 83 of the teeth 8. be able to. That is, the formation of the low magnetic permeability portion 82 and the bonding of the plurality of raw material plates can be performed in one step. Thereby, the manufacturing process of the stator core 7 can be simplified, and the manufacturing of the rotating electric machine can be facilitated. In addition, since no space is formed in the tip portions 83 of the teeth 8, an increase in noise and vibration of the rotating electric machine 1 can be suppressed.

Embodiment 6.
FIG. 17 is an exploded perspective view showing the stator core 7 of the rotary electric machine according to the sixth embodiment. The stator core 7 has at least one first core structure 70 and at least one second core structure 71 as core structures.

The first core structure portion 70 is a core structure portion in which the tip portions 83 of all the teeth 8 are not provided with the low magnetic permeability portions 82 . Of the three teeth 8 in each tooth group 81, the second core structure portion 71 is provided with low magnetic permeability portions 82 at the tip portions 83 of the two outer teeth 8 avoiding the central tooth 8. It is the core structure.

The configuration of the stator core 7 in the first embodiment is applied to the configuration of the second core structure portion 71 . Therefore, in the second core structure portion 71 , the space formed by the grooves 821 serves as the low magnetic permeability portion 82 . The low magnetic permeability portion 82 is provided over the entire range of the second core structure portion 71 in the direction along the main axis. Also, the low magnetic permeability portion 82 is provided parallel to the main axis.

In the stator core 7, the first core structure portions 70 and the second core structure portions 71 are alternately overlapped in the direction along the main axis. In this example, two first core structures 70 and one second core structure 71 are included in the stator core 7 as three core structures. The one first core structure portion 70, the second core structure portion 71 and the other first core structure portion 70 are sequentially overlapped in the direction along the main axis. Also, the dimensions of each of the first core structure parts 70 and the second core structure parts 71 in the direction along the main axis are the same as each other.

In the stator core 7, in the direction along the main axis, the low permeability portion 82 does not exist in the range where the first core structure portion 70 is arranged, and the low permeability portion 82 does not exist in the range where the second core structure portion 71 is arranged. A magnetic flux portion 82 is present. Accordingly, in the teeth 8 provided with the low magnetic permeability portions 82, the low magnetic permeability portions 82 partially exist in the direction along the main axis. Other configurations in the sixth embodiment are similar to those in the first embodiment.

In the rotary electric machine 1 according to Embodiment 6, the low magnetic permeability portion 82 partially exists in the direction along the main axis. Therefore, compared to the case where the low magnetic permeability portion 82 exists in the entire range of the stator core 7 in the direction along the main axis, it is possible to suppress the decrease in the amount of effective magnetic flux that contributes to the torque output. As a result, it is possible to more reliably suppress a decrease in torque output.

In Embodiment 6, stator core 7 includes two first core structure portions 70 and one second core structure portion 71 . However, as shown in FIG. 18, the stator core 7 may include one first core structure 70 and two second core structures 71 . In this case, one second core structure portion 71, the first core structure portion 70, and the other second core structure portion 71 are sequentially stacked in the direction along the main axis. Even in this way, the low magnetic permeability portion 82 can be partially present in the direction along the main axis, and the decrease in torque output can be suppressed more reliably.

Further, in Embodiment 6, the number of core structures included in the stator core 7 is three. However, the number of core structures included in the stator core 7 may be two or four or more. In this case, in the stator core 7, the first core structure portions 70 and the second core structure portions 71 are alternately stacked in the direction along the main axis.

Embodiment 7.
FIG. 19 is a longitudinal sectional view showing an elevator hoist according to Embodiment 7. FIG. An elevator hoisting machine 100 includes a rotating electrical machine 1 , a drive sheave 101 , a housing 102 , a frame 103 , a braking device 104 and a main shaft 105 .

The rotating electric machine 1 is a motor that generates driving force for rotating the drive sheave 101 . A rotating electric machine 1 has a rotor 2 and a stator 6 . The rotor 2 and stator 6 have a common axis as a main axis. A main shaft 105 and a cylindrical housing 102 are fixed to the frame 103 . The rotor 2 , stator 6 and housing 102 are arranged coaxially with the main shaft 105 .

Drive sheave 101 is rotatably supported by main shaft 105 via bearing 108 . As a result, drive sheave 101 is arranged coaxially with main shaft 105 . A rotor 2 is fixed to the drive sheave 101 .

The rotor 2 has a tubular rotor core 4 and a plurality of magnetic poles 5 provided on the outer peripheral surface of the rotor core 4 . Cylindrical rotor core 4 is integrally formed with drive sheave 101 . In this example, the material forming the rotor core 4 and the drive sheave 101 is cast iron. The stator 6 is fixed to the inner peripheral surface of the housing 102 . Other configurations of the rotating electrical machine 1 are the same as those of the rotating electrical machine 1 of the first embodiment.

The drive sheave 101 and the rotor 2 rotate about the main axis with respect to the main shaft 105 and the stator 6 by supplying three-phase AC power to the plurality of windings 10 . When the drive sheave 101 and the rotor 2 rotate, the housing 102 receives reaction force due to the rotation of the drive sheave 101 and the rotor 2 .

The drive sheave 101 is provided at a position outside the range of the stator 6 in the direction along the main axis. A plurality of main rope grooves 107 are provided along the circumferential direction of the drive sheave 101 on the outer peripheral surface of the drive sheave 101 . A plurality of main ropes for suspending a car and a counterweight (not shown) are wound around the drive sheave 101 along each main rope groove 107 . Rotation of drive sheave 101 causes the car and counterweight to move up and down in the hoistway.

The braking device 104 is provided inside the tubular rotor core 4 . The brake device 104 is a device that applies braking force to the drive sheave 101 and the rotor 2 . The brake device 104 has brake shoes (not shown) that can be displaced in the radial direction of the rotor 2 with respect to the rotor core 4 . The brake device 104 applies braking force to the drive sheave 101 and the rotor 2 by bringing brake shoes into contact with the inner peripheral surface of the rotor core 4 . Also, the brake device 104 releases the braking force to the drive sheave 101 and the rotor 2 by separating the brake shoes from the rotor core 4 .

An elevator hoisting machine 100 according to the seventh embodiment includes a rotating electrical machine 1 having a configuration similar to that of the first embodiment as a motor. Therefore, as in the first embodiment, it is possible to suppress a decrease in the torque output of the elevator hoisting machine 100 while reducing the torque ripple of the elevator hoisting machine 100 . As a result, it is possible to reduce the vibration of the car caused by the torque ripple of the rotary electric machine 1, and it is possible to reduce the shaking of the car during the operation of the elevator.

In Embodiment 7, the rotor 2 rotates integrally with the drive sheave 101 . However, the elevator hoist 100 may be a hoist having a geared motor in which a speed reducer including gears and the rotary electric machine 1 as a motor are integrated. In this case, the driving sheave 101 is rotated by the rotational force output from the speed reducer of the geared motor.

Also, instead of the rotary electric machine 1 according to the first embodiment, the configuration of the rotary electric machine 1 according to the second to sixth embodiments may be used as the configuration of the motor of the hoisting machine 100 of the elevator.

In each of the above-described embodiments, the rotating electrical machine in which the number of magnetic poles 5 of the rotor 2 is ten and the number of slots of the stator core 7 is nine, that is, the rotating electrical machine with ten poles and nine slots 1 is used. However, a rotating electrical machine in which the rotor 2 has eight magnetic poles 5 and the stator core 7 has nine slots, that is, a rotating electrical machine with 8 poles and 9 slots may be used as the rotating electrical machine 1 .

Further, in each of the above-described embodiments, a combination of 10 poles and 9 slots is defined as one unit A, and a combination of 10n poles and 9n slots, which is an integer n times the unit A, is the number of magnetic poles 5 of the rotor 2, It may be combined with the number of slots of the stator core 7 . In this case, the number of windings 10 is 9n. A combination of 8 poles and 9 slots is defined as one unit B, and a combination of 8n poles and 9n slots, which is an integer n times the unit B, is the number of magnetic poles 5 of the rotor 2 and the number of slots of the stator core 7. It may be combined with numbers. Also in this case, the number of windings 10 is 9n.

Further, in each of the above-described embodiments, the number of low magnetic permeability portions 82 provided at the tip portions 83 of the teeth 8 is one per tooth 8 . However, two or more low magnetic permeability portions 82 may be provided at the tip portion 83 of each tooth 8 .

Further, in each of the above-described embodiments, the back yoke 9 includes a plurality of back yoke members 91 arranged in an annular shape. However, the back yoke 9 may be an annular body integrally molded without being divided into a plurality of back yoke members.

In each of the above-described embodiments, a surface permanent magnet (SPM) rotating electric machine in which a plurality of magnetic poles 5 are arranged on the outer peripheral surface of the rotor core 4 is used as the rotating electric machine 1 . However, a rotary electric machine of the interior permanent magnet (IPM) type in which a plurality of magnetic poles 5 are embedded in the rotor core 4, or a compressor in which permanent magnets and magnetic salient poles are alternately arranged in the circumferential direction are used. A Quentpole-type rotating electrical machine may be used as the rotating electrical machine 1 .

Further, in each of the above-described embodiments, a rotating electrical machine having an inner rotor structure in which the rotor 2 is arranged inside the annular stator 6 is used as the rotating electrical machine 1 . However, a rotating electrical machine having an outer rotor structure in which the annular rotor 2 is arranged outside the stator 6 may be used as the rotating electrical machine 1 .

1 rotating electric machine 2 rotor 4 rotor core 5 magnetic pole 6 stator 7 stator core 8 tooth 9 back yoke 10 winding 81 tooth group 82 low magnetic permeability part 821 groove 824 Through hole, 825 Filler, 826 Crimped portion, 100 Elevator hoist.

Claims (10)

a rotor that rotates about an axis;
a stator facing the rotor with a gap in the radial direction of the rotor,
The rotor has a rotor core and a plurality of magnetic poles provided in the rotor core and arranged in a circumferential direction of the rotor,
The stator has a stator core and a plurality of windings provided on the stator core,
The stator core has a back yoke and a plurality of teeth projecting from the back yoke toward the rotor,
The plurality of teeth are spaced apart from each other in the circumferential direction of the stator,
each of the teeth has a tip facing the rotor,
The winding is wound around the tooth by concentrated winding,
The three teeth arranged continuously in the circumferential direction of the stator constitute a set of teeth,
The windings of the same phase are wound around the three teeth that constitute one tooth group,
In the set of teeth, a low magnetic permeability portion is provided at each of the tip portions of two of the three teeth on the outer side, avoiding the central tooth,
The magnetic permeability of the low magnetic permeability portion is lower than the magnetic permeability of the stator core,
rotating electric machine. In the set of teeth, in a cross section perpendicular to the axis, the low magnetic permeability portions provided on the two outer teeth are located at geometrically symmetrical positions with respect to the center line of the central teeth. is provided,
The rotary electric machine according to claim 1. a rotor that rotates about an axis;
a stator facing the rotor with a gap in the radial direction of the rotor,
The rotor has a rotor core and a plurality of magnetic poles provided in the rotor core and arranged in a circumferential direction of the rotor,
The stator has a stator core and a plurality of windings provided on the stator core,
The stator core has a back yoke and a plurality of teeth projecting from the back yoke toward the rotor,
The plurality of teeth are spaced apart from each other in the circumferential direction of the stator,
each of the teeth has a tip facing the rotor,
The winding is wound around the tooth by concentrated winding,
The three teeth arranged continuously in the circumferential direction of the stator constitute a set of teeth,
The windings of the same phase are wound around the three teeth that constitute one tooth group,
In the set of teeth, among the three teeth, a low magnetic permeability portion is provided at the tip portion of the other outer tooth while avoiding the center and one outer tooth,
The magnetic permeability of the low magnetic permeability portion is lower than the magnetic permeability of the stator core,
rotating electric machine. The low magnetic permeability portion is arranged at a position farther from the center line of the tooth in the circumferential direction of the stator than the center line of the tooth on which the low magnetic permeability portion is provided,
The rotary electric machine according to any one of claims 1 to 3. The low magnetic permeability part is a space formed by a groove provided at the tip of the tooth,
The rotary electric machine according to any one of claims 1 to 4. The low magnetic permeability portion is a space portion formed by a through hole provided at the tip portion of the tooth,
The rotary electric machine according to any one of claims 1 to 4. The low magnetic permeability portion is a filling material filled in a space portion provided at the tip portion of the tooth,
The rotary electric machine according to any one of claims 1 to 4. The low magnetic permeability portion is a crimped portion provided at the tip portion of the tooth,
The rotary electric machine according to any one of claims 1 to 4. In the tooth provided with the low magnetic permeability portion, the low magnetic permeability portion partially exists in a direction along the axis,
The rotary electric machine according to any one of claims 1 to 8. An elevator hoist comprising the rotating electric machine according to any one of claims 1 to 9.

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