JP2009219291A - Rotor for synchronous electric motor, and compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor for a synchronous electric motor that reduces vibration and noise. <P>SOLUTION: The rotor 20 for the synchronous electric motor includes a rotor iron core 1, which is formed by stacking electromagnetic steel plates and formed with each magnet insertion hole 2 along the outer peripheral edge, each permanent magnet 4 inserted into each magnet insertion hole 2 so as to compose the magnetic pole, and each outer-peripheral magnetic material region 6 formed between the outer peripheral edge of the rotor iron core 1 and each permanent magnet 4. Each nonmagnetic material region 5 is formed between the outer peripheral edge of the rotor iron core 1 and each permanent magnet 4 such that an area of each outer-peripheral magnetic material region 6 is small in the vicinity between the magnetic poles and the area is gradually increased toward the center of the magnetic pole. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotor of a synchronous motor using permanent magnets. Furthermore, it is related with the compressor carrying the synchronous motor using the rotor of the synchronous motor.

  A synchronous motor using a rotor in which a permanent magnet is arranged in a laminated iron core can increase the torque of the motor by using reluctance torque using a magnetic part on the outer periphery of the rotor. On the other hand, the direction of the magnetic flux generated from the permanent magnet disposed inside easily changes in the magnetic body portion on the outer periphery. Therefore, the direction of the magnetic flux may change suddenly during operation depending on the positional relationship between the magnetic poles of the rotor and the teeth of the stator. As a result, noise and vibration generated from the synchronous motor may increase.

  In order to solve this problem, the following techniques have been proposed. That is, the permanent magnet rotor of an electric motor having a permanent magnet piece in a laminated rotor core is inserted into a rectangular parallelepiped portion formed by a permanent magnet piece opening in order to reduce cogging torque with a simple configuration. The permanent magnet piece is made up of two types of permanent magnet materials, and has a shape that replenishes the central main material that is skewed in the axial direction of the central main material and the substantially rectangular parallelepiped portions on both sides thereof, and has a magnetic flux density higher than that of the central main material. A permanent magnet rotor composed of a low-magnitude permanent magnet piece has been proposed (see, for example, Patent Document 1).

  Further, for the purpose of increasing the electric motor efficiency per volume of the permanent magnet, the tooth portion is provided in the stator, and is opposed to the rotor with a gap therebetween. The rotor is provided with a soft magnetic body having a permanent magnet embedding hole and is rotatable about a rotation axis. The soft magnetic body has holes for embedding permanent magnets along the rotation axis. Permanent magnets are embedded in the permanent magnet embedding holes. A magnetic pole face of a permanent magnet has a normal line perpendicular to the rotation axis, and a rotor having a circular shape has been proposed (see, for example, Patent Document 2).

Furthermore, to reduce the armature reaction magnetic flux and improve the magnetic flux distribution of the outer peripheral core, to provide a high-efficiency permanent magnet motor with less noise and vibration, center the axis in the rotor core. The permanent magnet housing holes formed in the portions corresponding to the sides of the substantially regular polygon, the permanent magnets inserted into the magnet housing holes, and the outer peripheral cores of the permanent magnet housing holes are formed in the radial direction. And four or more slit holes spaced apart along the permanent magnet receiving hole, and the pitch of the radially outer end of the slit hole is made substantially equal, and the pitch of the radially inner end is made equal to that of the permanent magnet. A permanent magnet electric motor has been proposed in which the central part is enlarged and the distance from the central part to the end part is reduced (see, for example, Patent Document 3).
Japanese Patent Laid-Open No. 10-174324 JP 2006-14389 A JP 2005-94968 A

  However, as in Patent Document 1 and Patent Document 2, it is problematic to make the permanent magnet inclined with respect to the rotation axis or to have a circular shape. For example, when a permanent magnet is disposed on the surface of the rotor and directly opposed to the stator, a great effect can be obtained. However, when the permanent magnet is disposed inside the magnetic body, the permanent magnet is disposed inside the magnetic body on the surface of the permanent magnet. Since the direction of the magnetic flux is likely to change, the effect of devising the shape of the permanent magnet is smaller than when the permanent magnet is arranged on the rotor surface.

  Further, in the case of the technique described in Patent Document 3, the effect of suppressing the vibration and noise of the synchronous motor is obtained by restricting the change in the direction of the magnetic flux in the magnetic body on the rotor surface to some extent by the slit hole. be able to. However, the slit hole makes it difficult for reluctance torque to be generated, and there is a problem that the feature of the rotor in which the permanent magnet is arranged inside the rotor magnetic body cannot be used.

  The present invention is made to solve the above-described problems, and provides a rotor of a synchronous motor that can reduce vibration and noise, and a compressor using the rotor of the synchronous motor. Objective.

  A rotor of a synchronous motor according to the present invention is formed by laminating electromagnetic steel sheets, a rotor core in which a magnet insertion hole is formed along an outer peripheral edge, and a permanent magnet that is inserted into the magnet insertion hole and constitutes a magnetic pole And an outer peripheral magnetic region formed between the outer peripheral edge of the rotor core and the permanent magnet, and the area of the outer peripheral magnetic region is small near the magnetic poles and gradually increases toward the center of the magnetic poles As described above, a non-magnetic region is formed between the outer peripheral edge of the rotor core and the permanent magnet.

  In the rotor of the synchronous motor according to the present invention, the outer peripheral edge of the rotor core and the permanent magnet are arranged so that the area of the outer peripheral magnetic region is small in the vicinity of the magnetic poles and gradually increases toward the center of the magnetic poles. By forming the non-magnetic region between them, the change of the magnetic flux linked to the stator becomes gentle, the torque pulsation can be suppressed, and the vibration and noise of the synchronous motor can be suppressed.

Embodiment 1 FIG.
FIG. 1 to FIG. 11 are diagrams showing Embodiment 1, FIG. 1 is a perspective view of a rotor 20 of a synchronous motor, FIG. 2 is a cross-sectional view of part A in FIG. 1, and FIG. 4 is a cross-sectional view of part C of FIG. 1, FIG. 5 is a front view of the rotor 20 of the synchronous motor, FIG. 6 is a perspective view of the rotor 20 of the synchronous motor of Modification 1, and FIG. FIG. 8 is a perspective view of the rotor 20 of the synchronous motor according to the third modification, a front sectional view (b), and FIG. FIG. 10 is a perspective view (a) and a front view (b) of the rotor 20 of the synchronous motor of the modified example 4, and FIG. 10 shows the induced voltage waveform 9 of the synchronous motor using the rotor 20 of the synchronous motor shown in FIG. FIG. 11 shows a comparison with the induced voltage waveform 10 of the synchronous motor using the rotor 20 of the synchronous motor that does not have the magnetic region 5, and FIG. 11 shows the rotation of the synchronous motor shown in FIG. The waveform 29 of the cogging torque of the synchronous motor using 20 shows a comparison with the waveform 30 of the cogging torque of the synchronous motor using the rotor 20 of the synchronous motor without a non-magnetic region 5.

  The configuration of the rotor 20 of the synchronous motor will be described with reference to FIG. Hereinafter, the rotor 20 of the synchronous motor may be simply referred to as a rotor. A rotor 20 of a synchronous motor includes a rotor core 1 formed by laminating electromagnetic steel plates and a permanent magnet 4. The rotor core 1 includes magnet insertion holes 2 into which four permanent magnets 4 formed in a quadrangular shape along the outer peripheral edge of the rotor core 1 are inserted. Each magnet insertion hole 2 is a rectangle whose cross-sectional shape is long in the circumferential direction. Further, the rotor core 1 includes a rotation shaft fitting hole 3 in which a rotation shaft is fitted at the center. Further, the rotor core 1 includes a non-magnetic region 5 in the outer core portion of the permanent magnet 4 near both ends of the rotor core 1. Except for the magnet insertion hole 2, the rotation shaft fitting hole 3, and the nonmagnetic material region 5 of the rotor iron core 1, the magnetic material region (iron core part). A portion outside the magnet insertion hole 2 in the magnetic region is referred to as an outer peripheral magnetic region 6.

  The non-magnetic regions 5 are provided at both ends of the outer portion of each one-pole permanent magnet 4 in the vicinity of both ends in the axial direction. Triangular (substantially right-angled triangular) nonmagnetic regions 5 are formed at a total of four locations for each magnetic pole. The non-magnetic region 5 having a substantially right triangle has two sides forming a right angle of the right triangle arranged in parallel between the magnetic poles in the vicinity of the magnetic poles, and the other side on the axial end surface of the rotor core 1. Match.

  Therefore, as shown in FIGS. 2 to 3, the cross-sectional area of the non-magnetic region 5 becomes smaller from the axial end of the rotor core 1 toward the center. As shown in FIG. 4, the nonmagnetic region 5 does not exist near the center of the rotor core 1 in the axial direction.

  By forming the nonmagnetic region 5 as described above, the outer peripheral magnetic region 6 facing the outer peripheral surface of the permanent magnet 4 constituting each one magnetic pole has a large area near the center of the magnetic pole, and between the magnetic poles. The shape is reduced in area.

  When the rotor 20 of the synchronous motor rotates, the area of the outer peripheral magnetic region 6 facing the stator teeth is proportional to the rotation angle of the rotor in the case of the rotor without the non-magnetic region 5. Increase gradually.

  On the other hand, in the rotor 20 of the synchronous motor having the nonmagnetic material region 5, the area of the outer peripheral magnetic material region 6 facing the stator teeth is small with respect to the rotation angle of the rotor. The area increases gradually.

  When the outer peripheral magnetic region 6 is on the entire surface of the rotor, the magnetic flux generated from the permanent magnet 4 easily changes direction in the outer peripheral magnetic region 6. Therefore, if a part of the outer peripheral magnetic body region 6 starts to face the teeth of the stator during the rotation of the rotor, the magnetic flux suddenly concentrates on the facing portion with less magnetic resistance of the slot opening of the stator. The magnetic flux flowing into the teeth that have started facing each other suddenly increases. This sudden change in magnetic flux distorts the induced voltage generated in the stator windings, increasing the torque pulsation of the synchronous motor, which causes vibration and noise.

  In the synchronous motor rotor 20 according to the present embodiment, when the rotor rotates, the area where the outer peripheral magnetic region 6 is opposed to the teeth of the stator is small at first, and gradually as the rotation proceeds toward the magnetic pole center. In addition, the amount of increase in area increases. Therefore, the sudden flow of magnetic flux into the teeth is suppressed, distortion of the induced voltage generated in the winding is reduced, torque pulsation is suppressed, and a synchronous motor with less vibration and noise can be obtained.

  Usually, in the case of a rotor in which the permanent magnet 4 is disposed inside the rotor, the rotor core 1 in which electromagnetic steel plates are laminated is often used, and the rotor core 1 shown in FIG. The rotor 20 of a synchronous motor as shown in FIG. 1 is realizable by changing gradually the shape of the hole which punches out the electromagnetic steel plate for every electromagnetic steel plate to laminate | stack.

  However, in this case, since there are many types of electromagnetic steel sheets to be punched, a large-scale mold and press equipment are required.

  On the other hand, the rotor 20 of the synchronous motor of Modification 1 shown in FIG. 6 is formed by successively laminating a plurality of electromagnetic steel plates having the same shape, and the circumferential length of the nonmagnetic material region 5 is set in the direction of the rotation axis. On the other hand, it is changed in steps.

  By doing in this way, the kind of electromagnetic steel plate for comprising the nonmagnetic material area | region 5 can be reduced, and the scale of a metal mold | die and a press installation can be reduced.

Moreover, like the rotor 20 of the synchronous motor of the modification 2 shown to Fig.7 (a), the slit hole provided with several slit hole 7a, 7b, 7c, 7d which can open the nonmagnetic material area | region 5 to an axial direction. 7 may be used. The depth of the slit hole 7 is deeper as it is closer to the magnetic pole, and is made shallower as it gets closer to the center of the magnetic pole. That is, if the axial depths of the slit holes 7a, 7b, 7c, 7d are d7a, d7b, d7c, d7d,
d7a>d7b>d7c> d7d
It is.

  By comprising in this way, the effect close | similar to the nonmagnetic material area | region 5 shown in FIG. 1 is acquired. Moreover, since holes for punching out electromagnetic steel sheets to form the non-magnetic region 5 can be realized by changing the number thereof as shown in FIG. 7 (b), manufacturing with a small-scale mold and press equipment is possible. Is possible.

  A section A section of FIG. 7B shows a section of section A of FIG. The same applies to the B section to the E section.

  Moreover, like the rotor 20 of the synchronous motor of the modification 3 shown to Fig.8 (a), the nonmagnetic material area | region 5 is provided with several nonmagnetic space 8a, 8b, 8c, 8d from which the length of an axial direction differs. Realization is also possible by configuring the non-magnetic space 8.

In the case of FIG. 8A, in the nonmagnetic space 8, spaces having large volumes are arranged at both ends in the axial direction of the rotor, and spaces having a small volume (small dimensions in the axial direction) are arranged toward the vicinity of the center. . That is, when the axial lengths of the nonmagnetic spaces 8a, 8b, 8c, and 8d are L8a, L8b, L8c, and L8d,
L8a>L8b>L8c> L8d
It is.

  Further, the intervals between the nonmagnetic spaces 8a, 8b, 8c, and 8d are gradually increased toward the center in the axial direction. By disposing the nonmagnetic space 8 in this way, the density of the magnetic material in the axial direction of the portion changes, and the density of the magnetic material near the center in the axial direction increases, and the rotor of the synchronous motor shown in FIG. The shape of the outer peripheral magnetic body region 6 similar to 20 can be simulated. For this reason, the effect similar to the rotor 20 of the synchronous motor shown in FIG. 1 is acquired.

  In the case of the rotor 20 of the synchronous motor of FIG. 8A, the shape of the electromagnetic steel plates to be laminated can be configured in two types with or without holes for forming the nonmagnetic space 8, and thus further manufactured. The equipment can be downsized and the cost can be reduced.

  Since the rotor 20 of the synchronous motor according to the present embodiment has many slit-free portions in the outer peripheral magnetic body region 6 on the surface of the permanent magnet 4, reluctance torque can be used. Torque can be improved.

  Further, if the non-magnetic region 5 is provided between the magnetic poles near the rotor end face, the magnetic flux easily leaks from the portion of the permanent magnet 4 facing the non-magnetic region 5 in the axial direction. Means to detect the magnetic pole of the rotor using a sensor such as a Hall element, an amplifier, a Schmitt trigger circuit and an output transistor on a single chip of silicon). It becomes easy to pick up.

  In the case of the rotor in which the nonmagnetic material region 5 is provided between the magnetic poles near the rotor end face, the portion of the permanent magnet 4 facing the nonmagnetic material region 5 has a large magnetic resistance in the nonmagnetic material region 5 and has a peripheral magnetic property on the surface. Compared with the portion having the body region 6, the generated magnetic flux is reduced. As the permanent magnet 4 embedded in the rotor core 1, rare earth expensive permanent magnets 4 are often used, which is not always optimal from the viewpoint of cost performance.

  In this case, as shown in FIG. 9 (a), the shape of the permanent magnet 4 is made the same as that of the outer peripheral magnetic region 6, and the area with respect to the non-magnetic region 5 is reduced. With respect to the amount of permanent magnet 4 used, magnetic flux can be extracted effectively, and a rotor with good cost performance can be obtained.

  When the nonmagnetic space 8 shown in FIG. 8A is used as the nonmagnetic material region 5, the permanent magnet 4 having the shape as shown in FIG. A rotor capable of obtaining the same effect as the rotor with the magnet 4 inserted can be realized.

FIG. 10 and FIG. 11 show the induced voltage waveform 9 and the cogging torque waveform 29 of the synchronous motor using the synchronous motor rotor 20 shown in FIG. A synchronous motor having the following specifications was used.
(1) Stator: outer diameter φ100, inner diameter φ52, height (core width) 40 mm, 6 slots.
(2) Rotor: outer diameter φ50, height (core width) 40 mm, 4 poles.
(3) Non-magnetic region 5: a right-angled triangle, and the length of two sides of the right-angled triangle is set to be approximately 1/3 of the vertical and horizontal dimensions of the permanent magnet 4.
FIG. 10 shows an induced voltage waveform 9 of the synchronous motor using the rotor 20 of the synchronous motor shown in FIG. For comparison, an induced voltage waveform 10 of the synchronous motor using the rotor 20 of the synchronous motor that does not have the nonmagnetic region 5 is also shown.

  Compared to the induced voltage waveform 10 when using a rotor that does not have the nonmagnetic region 5 on the outer periphery of the rotor, the induced voltage waveform 9 of the synchronous motor using the rotor 20 of the synchronous motor of FIG. It can be seen that the distortion is reduced.

  FIG. 11 shows a cogging torque waveform 29 of the synchronous motor using the synchronous motor rotor 20 shown in FIG. For comparison, a waveform 30 of the cogging torque of the synchronous motor using the rotor 20 of the synchronous motor not having the nonmagnetic material region 5 is also shown. Accordingly, the cogging torque waveform 29 of the synchronous motor using the synchronous motor rotor 20 shown in FIG. 6 is the same as the cogging torque waveform 30 of the synchronous motor using the synchronous motor rotor 20 having no non-magnetic region 5. You can see that it is smaller.

Embodiment 2. FIG.
FIGS. 12 to 16 are diagrams showing the second embodiment, FIG. 12 is a perspective view of the rotor 20 of the synchronous motor, FIG. 13 is a perspective view of the rotor 20 of the synchronous motor of the first modification, and FIG. 14 is a modification. 15 is a perspective view of the rotor 20 of the synchronous motor of FIG. 2, FIG. 15 is a perspective view (a) and a front sectional view (b) of the rotor 20 of the synchronous motor of Modification 3, and FIG. It is the perspective view (a) and front view (b) of the child 20.

  The configuration of the rotor 20 of the synchronous motor will be described with reference to FIG. Hereinafter, the rotor 20 of the synchronous motor may be simply referred to as a rotor. A rotor 20 of a synchronous motor includes a rotor core 1 formed by laminating electromagnetic steel plates and a permanent magnet 4. The rotor core 1 includes magnet insertion holes 2 into which four permanent magnets 4 formed in a quadrangular shape along the outer peripheral edge of the rotor core 1 are inserted. Each magnet insertion hole 2 is a rectangle whose cross-sectional shape is long in the circumferential direction. Further, the rotor core 1 includes a rotation shaft fitting hole 3 in which a rotation shaft is fitted at the center. Further, the rotor core 1 includes a non-magnetic region 5 outside the permanent magnet 4 near the axial center of the rotor core 1. Except for the magnet insertion hole 2, the rotation shaft fitting hole 3, and the nonmagnetic material region 5 of the rotor iron core 1, the magnetic material region (iron core part). A portion outside the magnet insertion hole 2 in the magnetic region is referred to as an outer peripheral magnetic region 6.

  The non-magnetic region 5 is provided at both ends of one magnetic pole in the vicinity of the axial center of the rotor core 1. There are two non-magnetic regions 5 per magnetic pole.

  The shape of the nonmagnetic material region 5 is a substantially isosceles triangle as viewed from the front. And the base of an isosceles triangle is located in the vicinity of between the magnetic poles and in parallel between the magnetic poles.

  Accordingly, the cross-sectional area of the non-magnetic region 5 is gradually reduced in the vicinity of the adjacent magnetic poles from the vicinity of the axial center of the rotor core 1 toward both ends in the axial direction.

  As a result, the outer peripheral magnetic body region 6 facing the outer peripheral surface of the permanent magnet 4 constituting one magnetic pole has a shape in which the area is large near the center of the magnetic pole and the area is small near the magnetic pole.

  When the rotor rotates, the area of the outer peripheral magnetic region 6 facing the stator teeth gradually increases in proportion to the rotation angle of the rotor in the case of the rotor without the nonmagnetic region 5. .

  On the other hand, in the rotor having the non-magnetic region 5, the increase in the facing area is small at first with respect to the rotation angle of the rotor, and the increase in the area gradually increases.

  When the nonmagnetic material region 5 is present on the rotor surface, the magnetic flux generated from the permanent magnet 4 easily changes direction in the outer magnetic material region 6, so that the outer magnetic material region 6 is rotated during rotation of the rotor. When a part of the wire begins to face the teeth of the stator, the magnetic flux suddenly concentrates on the facing portion having a lower magnetic resistance than the slot opening of the stator, so that the magnetic flux flowing into the teeth starting to face suddenly increases. . This sudden change in magnetic flux distorts the induced voltage generated in the stator windings, increasing the torque pulsation of the synchronous motor and causing vibration and noise.

  When the rotor rotates, the rotor 20 of the synchronous motor according to the present embodiment has a small area where the outer peripheral magnetic region 6 faces the teeth of the stator, and gradually increases as the rotation proceeds toward the center of the magnetic pole. Increase in area increases. Therefore, the sudden flow of magnetic flux into the teeth is suppressed, distortion of the induced voltage generated in the winding is reduced, torque pulsation is suppressed, and a synchronous motor with less vibration and noise can be obtained.

  Usually, in the case of a rotor in which the permanent magnet 4 is disposed inside the rotor, the rotor core 1 in which electromagnetic steel plates are laminated is often used, and the rotor core 1 shown in FIG. The rotor 20 of a synchronous motor as shown in FIG. 12 is realizable by changing gradually the shape of the hole which punches out the electromagnetic steel plate for every electromagnetic steel plate to laminate | stack.

  Moreover, you may make it change the non-magnetic-material area | region 5 to step shape with respect to the rotating shaft direction like the rotor 20 of the synchronous motor of the modification 1 shown in FIG.

  By doing in this way, the kind of electromagnetic steel plate for comprising the nonmagnetic material area | region 5 can be reduced, and the scale of a metal mold | die and a press installation can be reduced.

Moreover, like the rotor 20 of the synchronous motor of the modification 2 shown in FIG. 14, the nonmagnetic material region 5 is configured by the slit hole 7 having a plurality of slit holes 7a, 7b, 7c, 7d that can be opened in the axial direction. May be. The length of the slit hole 7 in the axial direction is longer as it is closer to the magnetic pole, and shorter as it is closer to the magnetic pole center. That is, if the axial lengths of the slit holes 7a, 7b, 7c, 7d are d7a, d7b, d7c, d7d, d7e,
d7a>d7b>d7c> d7d
It is.

  By comprising in this way, the effect close | similar to the nonmagnetic material area | region 5 shown in FIG. 12 is acquired. In addition, since the change in magnetic flux can be moderated, the cogging torque can be reduced. Further, since holes for punching out electromagnetic steel sheets to form the non-magnetic region 5 can be realized by changing the number thereof, it is possible to manufacture with a small-scale mold and press equipment.

  Moreover, like the rotor 20 of the synchronous motor of the modification 3 shown to Fig.15 (a), the nonmagnetic body area | region 5 is provided with several nonmagnetic space 8a, 8b, 8c, 8d from which the length of an axial direction differs. Realization is also possible by configuring the non-magnetic space 8.

In the case of FIG. 15A, the nonmagnetic space 8 has a space with a large volume in the vicinity of the center in the axial direction, and a space with a smaller volume (a smaller size in the axial direction) is disposed toward both ends. That is, when the axial lengths of the nonmagnetic spaces 8a, 8b, 8c, and 8d are L8a, L8b, L8c, and L8d,
L8a>L8b>L8c> L8d
It is.

  Further, as shown in FIG. 15B, the intervals between the nonmagnetic spaces 8a, 8b, 8c, and 8d are gradually narrowed toward the axial center. By disposing the nonmagnetic space 8 in this manner, the density of the magnetic body in the axial direction changes, and the density of the magnetic body at both ends in the axial direction increases, which is the same as the rotor 20 of the synchronous motor shown in FIG. The shape of the outer peripheral magnetic body region 6 can be simulated. For this reason, the rotor 20 of the synchronous motor of the modification 3 shown to Fig.15 (a) can acquire the effect similar to the rotor 20 of the synchronous motor shown in FIG.

  Since the rotor 20 of the synchronous motor according to the present embodiment has many slit-free portions in the outer peripheral magnetic body region 6 on the surface of the permanent magnet 4, reluctance torque can be used. Torque can be improved.

  In the case of the rotor 20 of the synchronous motor shown in FIGS. 12 to 15, the portion of the permanent magnet 4 that faces the nonmagnetic material region 5 has a large magnetic resistance in the nonmagnetic material region 5, and the outer peripheral magnetic material region 6 is formed on the surface. Compared with the part which has, the generated magnetic flux decreases. The permanent magnet 4 used for the rotor in which the permanent magnet 4 is embedded in the rotor core 1 is often a rare earth expensive permanent magnet 4 and is not necessarily optimal from the viewpoint of cost performance.

  In this case, as shown in FIG. 16 (a), a plurality of pieces (per magnetic pole in the case of FIG. 16 (a)) are formed so that the shape of the permanent magnet 4 is the same as that of the outer peripheral magnetic body region 6. ) Permanent magnet 4.

  By doing so, the entire magnetic flux amount of the permanent magnet 4 is reduced. However, the area with respect to the non-magnetic material region 5 can be reduced, and the magnetic flux can be effectively extracted with respect to the amount of use of the permanent magnet 4, and a rotor with good cost performance can be obtained.

  When the nonmagnetic region 5 shown in FIG. 15 is used, by inserting the permanent magnet 4 as shown in FIG. 16B, the same as the rotor in which the permanent magnet 4 having the same shape as the outer peripheral magnetic region 6 is inserted. The effect is obtained.

  12 to 15, the rotor outer peripheral core portion of the nonmagnetic body region 5 and the core portion between the nonmagnetic body region 5 and the magnet insertion hole 2 are made of a thin magnetic body. In particular, the rigidity of the thin portion of the outer peripheral iron core portion is low. On the other hand, since the entire outer peripheral magnetic region 6 is made of a magnetic material such as an electromagnetic steel plate, the rigidity is high. The rotor 20 of the synchronous motor shown in FIGS. 12 to 15 in which the outer peripheral magnetic body region 6 is arranged near the end surface in the axial direction is not easily deformed by external stress. For this reason, it is hard to produce the damage by the assembly at the time of manufacture, and conveyance.

Embodiment 3 FIG.
FIGS. 17 to 21 are diagrams showing the third embodiment. FIG. 17 is a perspective view of the rotor 20 of the synchronous motor, FIG. 18 is a perspective view of the rotor 20 of the synchronous motor of the first modification, and FIG. 2 is a perspective view of the rotor 20 of the synchronous motor of FIG. 2, FIG. 20 is a perspective view (a) and a front sectional view (b) of the rotor 20 of the synchronous motor of Modification 3, and FIG. 21 is the rotation of the synchronous motor of Modification 4. It is the perspective view (a) and front view (b) of the child 20.

  The configuration of the rotor 20 of the synchronous motor will be described with reference to FIG. Hereinafter, the rotor 20 of the synchronous motor may be simply referred to as a rotor. A rotor 20 of a synchronous motor includes a rotor core 1 formed by laminating electromagnetic steel plates and a permanent magnet 4. The rotor core 1 includes magnet insertion holes 2 into which four permanent magnets 4 formed in a quadrangular shape along the outer peripheral edge of the rotor core 1 are inserted. Each magnet insertion hole 2 is a rectangle whose cross-sectional shape is long in the circumferential direction. Further, the rotor core 1 includes a rotation shaft fitting hole 3 in which a rotation shaft is fitted at the center. Furthermore, the rotor core 1 includes a non-magnetic region 5 outside the permanent magnet 4 near both ends of the rotor core 1. Except for the magnet insertion hole 2, the rotation shaft fitting hole 3, and the nonmagnetic material region 5 of the rotor iron core 1, the magnetic material region (iron core part). A portion outside the magnet insertion hole 2 in the magnetic region is referred to as an outer peripheral magnetic region 6.

  The nonmagnetic material regions 5 are provided at two locations per magnetic pole. Each non-magnetic region 5 is divided at both ends in the axial direction of the rotor core 1 and is arranged on a diagonal line of the permanent magnet 4 constituting one magnetic pole. That is, one nonmagnetic region 5 is provided in the vicinity of one adjacent magnetic pole. The other nonmagnetic region 5 is provided in the vicinity of the other adjacent magnetic pole.

  The cross-sectional area gradually decreases in the vicinity of the adjacent magnetic poles as it approaches the center as viewed from the axial direction of the rotor. As a result, the outer peripheral magnetic body region 6 facing the outer peripheral surface of the permanent magnet 4 constituting one magnetic pole has a shape in which the area is large near the center of the magnetic pole and the area is small near the magnetic pole.

  Triangular (substantially right-angled triangular) non-magnetic regions 5 are formed in two places per magnetic pole. The non-magnetic region 5 having a substantially right triangle has two sides forming a right angle of the right triangle arranged in parallel between the magnetic poles in the vicinity of the magnetic poles, and the other side on the axial end surface of the rotor core 1. Match.

  Therefore, the cross-sectional area of the non-magnetic region 5 becomes smaller from the axial end of the rotor core 1 toward the center. Near the center of the rotor core 1 in the axial direction, the non-magnetic region 5 does not exist.

  By forming the nonmagnetic region 5 as described above, the outer peripheral magnetic region 6 facing the outer peripheral surface of the permanent magnet 4 constituting each one magnetic pole has a large area near the center of the magnetic pole, and between the magnetic poles. The shape is reduced in area.

  When the rotor 20 of the synchronous motor rotates, the area of the outer peripheral magnetic region 6 facing the stator teeth is proportional to the rotation angle of the rotor in the case of the rotor without the non-magnetic region 5. Increase gradually.

  On the other hand, in the rotor 20 of the synchronous motor having the nonmagnetic material region 5, the area of the outer peripheral magnetic material region 6 facing the stator teeth is small with respect to the rotation angle of the rotor. The area increases gradually.

  When the outer peripheral magnetic region 6 is on the entire surface of the rotor, the magnetic flux generated from the permanent magnet 4 easily changes direction in the outer peripheral magnetic region 6. Therefore, if a part of the outer peripheral magnetic body region 6 starts to face the teeth of the stator during the rotation of the rotor, the magnetic flux suddenly concentrates on the facing portion having a lower magnetic resistance than the slot opening of the stator. The magnetic flux flowing into the teeth starting with a sudden increase. This sudden change in magnetic flux distorts the induced voltage generated in the stator windings, increasing the torque pulsation of the synchronous motor, which causes vibration and noise.

  In the synchronous motor rotor 20 according to the present embodiment, when the rotor rotates, the area where the outer peripheral magnetic region 6 is opposed to the teeth of the stator is small at first, and gradually as the rotation proceeds toward the magnetic pole center. In addition, the amount of increase in area increases. Therefore, the sudden flow of magnetic flux into the teeth is suppressed, distortion of the induced voltage generated in the winding is reduced, torque pulsation is suppressed, and a synchronous motor with less vibration and noise can be obtained.

  This is the same effect as the rotor in which the permanent magnet 4 is arranged on the surface and the magnetic pole is skewed. In addition, since the change in magnetic flux can be moderated, the cogging torque can be reduced.

  Usually, in the case of a rotor in which the permanent magnet 4 is arranged inside the rotor, the rotor core 1 in which electromagnetic steel plates are laminated is often used, and the rotor 20 of the synchronous motor shown in FIG. Similarly to the above, it can be realized by gradually changing the shape of the hole through which the electromagnetic steel sheet is punched in order to constitute the non-magnetic region 5 for each electromagnetic steel sheet to be laminated.

  Further, like the rotor 20 of the synchronous motor according to the first modification shown in FIG. 18, the nonmagnetic material region 5 is changed stepwise with respect to the rotation axis direction, thereby forming the nonmagnetic material region 5. The type of steel sheet can be reduced.

Or you may comprise the non-magnetic-material area | region 5 by several slit hole 7a, 7b, 7c, 7d like the rotor 20 of the synchronous motor of the modification 2 shown in FIG. The length of the slit hole 7 in the axial direction is longer as it is closer to the magnetic pole, and shorter as it is closer to the magnetic pole center. That is, if the axial lengths of the slit holes 7a, 7b, 7c, 7d are d7a, d7b, d7c, d7d, d7e,
d7a>d7b>d7c> d7d
It is.

  By configuring in this way, an effect close to the non-magnetic region 5 of FIG. 17 is obtained, and the holes for punching the electromagnetic steel plate for configuring the non-magnetic region 5 can be realized by changing the number of the holes, Small-scale molds and press facilities can be manufactured.

  Like the rotor 20 of the synchronous motor of the modification 3 shown to Fig.20 (a), the nonmagnetic material area | region 5 is provided with several nonmagnetic space 8a, 8b, 8c, 8d, 8e from which the length of an axial direction differs. Realization is also possible by configuring the non-magnetic space 8.

In the case of FIG. 20A, in the nonmagnetic space 8, a space with a small volume is disposed near the center in the axial direction, and a space with a larger volume (a larger dimension in the axial direction) is disposed toward both ends. That is, when the axial lengths of the nonmagnetic spaces 8a, 8b, 8c, 8d, and 8e are L8a, L8b, L8c, L8d, and L8e,
L8a>L8b>L8c>L8d> L8e
It is.

  As shown in FIG. 20B, the intervals between the nonmagnetic spaces 8a, 8b, 8c, 8d, and 8e are gradually increased toward the center in the axial direction. By disposing the nonmagnetic space 8 in this way, the density of the magnetic body in the axial direction changes, and the density of the magnetic body at both ends in the axial direction increases, which is the same as the rotor 20 of the synchronous motor shown in FIG. The shape of the outer peripheral magnetic body region 6 can be simulated. For this reason, the rotor 20 of the synchronous motor of the modification 3 shown to Fig.20 (a) can acquire the effect similar to the rotor 20 of the synchronous motor shown in FIG.

  In the case of the rotor 20 of the synchronous motor shown in FIG. 20A, the electromagnetic steel plates to be laminated include two types of holes having different positions for forming the nonmagnetic space 8 and holes for forming the nonmagnetic space 8. Since there are a total of three types, one with no, manufacturing equipment can be reduced in size and cost.

  Since the rotor 20 of the synchronous motor according to the present embodiment has many slit-free portions in the outer peripheral magnetic body region 6 on the surface of the permanent magnet 4, reluctance torque can be used. Torque can be improved.

  Further, in the case of the rotor 20 of the synchronous motor according to the present embodiment, since the adjacent magnetic poles can be largely separated by the nonmagnetic material region 5, the short circuit of the magnetic flux between the magnetic poles can be reduced, and more magnetic flux can be transferred to the rotor. Can be put on the surface.

  In the case of the rotor 20 of the synchronous motor shown in FIGS. 17 to 20, the portion of the permanent magnet 4 facing the nonmagnetic material region 5 has a large magnetic resistance of the nonmagnetic material region 5, and the outer peripheral magnetic material region 6 is formed on the surface. Compared with the part which has, the generated magnetic flux decreases. The permanent magnet 4 used for the rotor in which the permanent magnet 4 is embedded in the rotor core 1 is often a rare earth expensive permanent magnet 4 and is not necessarily optimal from the viewpoint of cost performance.

  In this case, as shown in FIG. 21A, the shape of the permanent magnet 4 is the same as that of the outer peripheral magnetic body region 6, and the area with respect to the non-magnetic body region 5 is reduced. With respect to the amount of permanent magnet 4 used, magnetic flux can be extracted effectively, and a rotor with good cost performance can be obtained.

  When the nonmagnetic space 8 shown in FIG. 20A is used as the nonmagnetic material region 5, the permanent magnet 4 having the shape as shown in FIG. A rotor capable of obtaining the same effect as the rotor with the magnet 4 inserted can be realized.

Embodiment 4 FIG.
FIGS. 22 to 26 are diagrams showing the fourth embodiment. FIG. 22 is a perspective view of the rotor 20 of the synchronous motor, FIG. 23 is a perspective view of the rotor 20 of the synchronous motor of the first modification, and FIG. 25 is a perspective view of the rotor 20 of the synchronous motor of FIG. 2, FIG. 25 is a perspective view (a) and a front sectional view (b) of the rotor 20 of the synchronous motor of Modification 3, and FIG. 26 is the rotation of the synchronous motor of Modification 4. It is the perspective view (a) and front view (b) of the child 20.

  The configuration of the rotor 20 of the synchronous motor will be described with reference to FIG. Hereinafter, the rotor 20 of the synchronous motor may be simply referred to as a rotor. A rotor 20 of a synchronous motor includes a rotor core 1 formed by laminating electromagnetic steel plates and a permanent magnet 4. The rotor core 1 includes magnet insertion holes 2 into which four permanent magnets 4 formed in a quadrangular shape along the outer peripheral edge of the rotor core 1 are inserted. Each magnet insertion hole 2 is a rectangle whose cross-sectional shape is long in the circumferential direction. Further, the rotor core 1 includes a rotation shaft fitting hole 3 in which a rotation shaft is fitted at the center. Further, the rotor core 1 includes a non-magnetic region 5 outside the magnetic pole portions (permanent magnets 4) near both ends of the rotor core 1. Except for the magnet insertion hole 2, the rotation shaft fitting hole 3, and the nonmagnetic material region 5 of the rotor iron core 1, the magnetic material region (iron core part). A portion outside the magnet insertion hole 2 in the magnetic region is referred to as an outer peripheral magnetic region 6.

  The nonmagnetic material regions 5 are provided at two locations per magnetic pole. Each non-magnetic region 5 is divided at both ends in the axial direction of the rotor core 1 and is arranged on a diagonal line of the permanent magnet 4 constituting one magnetic pole. That is, one nonmagnetic region 5 is provided in the vicinity of one adjacent magnetic pole. The other nonmagnetic region 5 is provided in the vicinity of the other adjacent magnetic pole.

  The cross-sectional area increases gradually toward the center as seen from the axial direction of the rotor while being gradually arranged in the vicinity of adjacent magnetic poles. As a result, the outer peripheral magnetic body region 6 facing the outer peripheral surface of the permanent magnet 4 constituting one magnetic pole has a shape in which the area is large near the center of the magnetic pole and the area is small near the magnetic pole.

  Triangular (substantially right-angled triangular) non-magnetic regions 5 are formed in two places per magnetic pole. The non-magnetic region 5 having a substantially right-angled triangle has two sides forming a right angle of the right-angled triangle arranged in parallel between the magnetic poles in the vicinity of the magnetic poles, and the other side is substantially the center in the axial direction of the rotor core 1. It arrange | positions in the circumferential direction in a part.

  Therefore, the cross-sectional area of the non-magnetic region 5 increases as it goes from the axial end of the rotor core 1 to the vicinity of the center.

  When the rotor 20 of the synchronous motor rotates, the area of the outer peripheral magnetic region 6 facing the stator teeth is proportional to the rotation angle of the rotor in the case of the rotor without the non-magnetic region 5. Increase gradually.

  On the other hand, in the rotor 20 of the synchronous motor having the nonmagnetic material region 5, the area of the outer peripheral magnetic material region 6 facing the stator teeth is small with respect to the rotation angle of the rotor. The area increases gradually.

  When the outer peripheral magnetic region 6 is on the entire surface of the rotor, the magnetic flux generated from the permanent magnet 4 easily changes direction in the outer peripheral magnetic region 6. Therefore, if a part of the outer peripheral magnetic body region 6 starts to face the teeth of the stator during the rotation of the rotor, the magnetic flux suddenly concentrates on the facing portion having a lower magnetic resistance than the slot opening of the stator. The magnetic flux flowing into the teeth starting with a sudden increase. This sudden change in magnetic flux distorts the induced voltage generated in the stator windings, increasing the torque pulsation of the synchronous motor, which causes vibration and noise.

  In the synchronous motor rotor 20 according to the present embodiment, when the rotor rotates, the area where the outer peripheral magnetic region 6 is opposed to the teeth of the stator is small at first, and gradually as the rotation proceeds toward the magnetic pole center. In addition, the amount of increase in area increases. Therefore, the sudden flow of magnetic flux into the teeth is suppressed, distortion of the induced voltage generated in the winding is reduced, torque pulsation is suppressed, and a synchronous motor with less vibration and noise can be obtained.

  This is the same effect as the rotor in which the permanent magnet 4 is arranged on the surface and the magnetic pole is skewed. In addition, since the change in magnetic flux can be moderated, the cogging torque can be reduced.

  Usually, in the case of a rotor in which the permanent magnet 4 is disposed inside the rotor, the rotor core 1 in which electromagnetic steel plates are laminated is often used, and the rotor core 1 shown in FIG. The rotor 20 of a synchronous motor as shown in FIG. 22 is realizable by changing gradually the shape of the hole which punches out the electromagnetic steel plate for every electromagnetic steel plate to laminate | stack.

  Moreover, like the rotor 20 of the synchronous motor of the modification 1 shown in FIG. 23, the nonmagnetic material region 5 is changed stepwise with respect to the rotation axis direction, thereby forming the electromagnetic material constituting the nonmagnetic material region 5. The type of steel sheet can be reduced.

Or you may comprise the nonmagnetic material area | region 5 by several slit hole 7a, 7b, 7c, 7d like the rotor 20 of the synchronous motor of the modification 2 shown in FIG. The length of the slit hole 7 in the axial direction is longer as it is closer to the magnetic pole, and shorter as it is closer to the magnetic pole center. That is, if the axial lengths of the slit holes 7a, 7b, 7c, 7d are d7a, d7b, d7c, d7d, d7e,
d7a>d7b>d7c> d7d
It is.

  By configuring in this way, an effect close to the nonmagnetic region 5 of FIG. 22 is obtained, and holes for punching the electromagnetic steel sheet for configuring the nonmagnetic region 5 can be realized by changing the number of the holes, Small-scale molds and press facilities can be manufactured.

  Like the rotor 20 of the synchronous motor of the modification 3 shown to Fig.25 (a), the nonmagnetic material area | region 5 is provided with several nonmagnetic space 8a, 8b, 8c, 8d, 8e from which the length of an axial direction differs. Realization is also possible by configuring the non-magnetic space 8.

In the case of FIG. 25A, the nonmagnetic space 8 has a space with a large volume in the vicinity of the center in the axial direction, and a space with a small volume (small size in the axial direction) is disposed toward both ends. That is, when the axial lengths of the nonmagnetic spaces 8a, 8b, 8c, 8d, and 8e are L8a, L8b, L8c, L8d, and L8e,
L8a>L8b>L8c>L8d> L8e
It is.

  Further, as shown in FIG. 25B, the intervals between the nonmagnetic spaces 8a, 8b, 8c, 8d, and 8e are gradually narrowed toward the axial center. By arranging the nonmagnetic space 8 in this way, the density of the magnetic body in the axial direction changes, and the density of the magnetic body at both ends in the axial direction increases, which is similar to the rotor 20 of the synchronous motor shown in FIG. The shape of the outer peripheral magnetic body region 6 can be simulated. For this reason, the rotor 20 of the synchronous motor of the modification 3 shown to Fig.25 (a) can acquire the effect similar to the rotor 20 of the synchronous motor shown in FIG.

  In the case of the rotor 20 of the synchronous motor shown in FIG. 25A, the electromagnetic steel sheets to be stacked are divided into two types having different hole positions for forming the nonmagnetic space 8 and holes for forming the nonmagnetic space 8. Since there are a total of three types, one with no, manufacturing equipment can be reduced in size and cost.

  Since the rotor 20 of the synchronous motor according to the present embodiment has many slit-free portions in the outer peripheral magnetic body region 6 on the surface of the permanent magnet 4, reluctance torque can be used. Torque can be improved.

  Further, in the case of the rotor 20 of the synchronous motor according to the present embodiment, since the adjacent magnetic poles can be largely separated by the nonmagnetic material region 5, the short circuit of the magnetic flux between the magnetic poles can be reduced, and more magnetic flux can be transferred to the rotor. Can be put on the surface.

  In the case of the rotor 20 of the synchronous motor shown in FIGS. 22 to 24, the portion of the permanent magnet 4 facing the nonmagnetic material region 5 has a large magnetic resistance in the nonmagnetic material region 5, and the outer peripheral magnetic material region 6 is formed on the surface. Compared with the part which has, the generated magnetic flux decreases. The permanent magnet 4 used for the rotor in which the permanent magnet 4 is embedded in the rotor core 1 is often a rare earth expensive permanent magnet 4 and is not necessarily optimal from the viewpoint of cost performance.

  In this case, as shown in FIG. 26 (a), the shape of the permanent magnet 4 is made the same as that of the outer peripheral magnetic body region 6 and the area for the non-magnetic body region 5 is reduced. With respect to the amount of permanent magnet 4 used, magnetic flux can be extracted effectively, and a rotor with good cost performance can be obtained.

  When the nonmagnetic space 8 shown in FIG. 25A is used as the nonmagnetic material region 5, the permanent magnet 4 having the shape as shown in FIG. A rotor capable of obtaining the same effect as the rotor with the magnet 4 inserted can be realized.

  22 to 25, the rotor outer peripheral core part of the nonmagnetic material region 5 and the iron core part between the nonmagnetic material region 5 and the magnet insertion hole 2 are made of a thin magnetic material. In particular, the rigidity of the thin portion of the outer peripheral iron core portion is low. On the other hand, since the entire outer peripheral magnetic region 6 is made of a magnetic material such as an electromagnetic steel plate, the rigidity is high. The rotor 20 of the synchronous motor shown in FIGS. 22 to 25 in which the outer peripheral magnetic body region 6 is arranged near the end surface in the axial direction is not easily deformed by external stress. For this reason, it is hard to produce the damage by the assembly at the time of manufacture, and conveyance.

Embodiment 5 FIG.
FIG. 27 is a diagram showing the fifth embodiment and shows the compressor 11. A synchronous motor 12 using the rotor 20 of the synchronous motor according to any one of the first to fourth embodiments is mounted on the compressor 11.

  The compressor 11 compresses the refrigerant with the internal compression mechanism 13, sends the refrigerant compressed through the refrigerant pipe 14 to the refrigeration cycle (condenser, decompressor, evaporator, etc.), and flows again through the refrigerant pipe 14. Perform compression.

  By driving the compression mechanism unit 13 with the synchronous motor 12 using the rotor 20 of the synchronous motor according to any one of the first to fourth embodiments, the vibration of the compressor 11 is suppressed. Since the refrigerant piping 14 through which the refrigerant passes vibrates using the compressor 11 as an excitation source, the vibration of the refrigerant piping 14 can be suppressed by suppressing the vibration of the compressor 11, and the deterioration of the metal such as metal fatigue of the refrigerant piping 14 due to the vibration. Can be prevented.

  As an application example of the present invention, application to the synchronous motor 12 used for the compressor 11 and application to the compressor 11 used for the air conditioner are possible.

FIG. 3 is a diagram showing the first embodiment, and is a perspective view of a rotor 20 of the synchronous motor. FIG. 2 shows the first embodiment, and is a cross-sectional view of a portion A in FIG. 1. FIG. 3 is a diagram showing the first embodiment, and is a cross-sectional view of a B portion in FIG. 1. FIG. 2 is a diagram showing the first embodiment, and is a cross-sectional view of a C portion in FIG. 1. FIG. 3 shows the first embodiment and is a front view of a rotor 20 of the synchronous motor. FIG. 5 shows the first embodiment, and is a perspective view of a rotor 20 of a synchronous motor according to a first modification. FIG. 5 shows the first embodiment, and is a perspective view (a) and a cross-sectional view (b) of A to E parts of a rotor 20 of a synchronous motor according to a second modification. FIG. 5 shows the first embodiment, and is a perspective view (a) and a front sectional view (b) of a rotor 20 of a synchronous motor according to a third modification. It is a figure which shows Embodiment 1, and is the perspective view (a) and front view (b) of the rotor 20 of the synchronous motor of the modification 4. FIG. 6 is a diagram showing the first embodiment, in which the induced voltage waveform 9 of the synchronous motor using the synchronous motor rotor 20 shown in FIG. 6 is represented by the synchronous motor using the synchronous motor rotor 20 that does not have the non-magnetic material region 5. FIG. The figure compared with the induced voltage waveform 10 of. 6 is a diagram illustrating the first embodiment, and shows a waveform 29 of a cogging torque of the synchronous motor using the rotor 20 of the synchronous motor shown in FIG. 6 and a synchronization using the rotor 20 of the synchronous motor not having the nonmagnetic region 5. FIG. The figure compared with the waveform 30 of the cogging torque of an electric motor. FIG. 5 shows the second embodiment and is a perspective view of the rotor 20 of the synchronous motor. FIG. 9 is a diagram illustrating the second embodiment, and is a perspective view of a rotor 20 of the synchronous motor according to the first modification. FIG. 9 is a diagram illustrating the second embodiment, and is a perspective view of a rotor 20 of a synchronous motor according to a second modification. It is a figure which shows Embodiment 2, and is a perspective view (a) and front sectional drawing (b) of the rotor 20 of the synchronous motor of the modification 3. FIG. It is a figure which shows Embodiment 2, and is a perspective view (a) and front view (b) of the rotor 20 of the synchronous motor of the modification 4. FIG. FIG. 9 shows the third embodiment and is a perspective view of the rotor 20 of the synchronous motor. FIG. 12 is a diagram showing the third embodiment, and is a perspective view of the rotor 20 of the synchronous motor of the first modification. FIG. 10 is a diagram illustrating the third embodiment, and is a perspective view of a rotor 20 of a synchronous motor according to a second modification. It is a figure which shows Embodiment 3, and is a perspective view (a) and front sectional drawing (b) of the rotor 20 of the synchronous motor of the modification 3. FIG. It is a figure which shows Embodiment 3, and is a perspective view (a) and front sectional drawing (b) of the rotor 20 of the synchronous motor of the modification 3. FIG. FIG. 10 shows the fourth embodiment and is a perspective view of the rotor 20 of the synchronous motor. FIG. 10 is a diagram showing the fourth embodiment, and is a perspective view of a rotor 20 of the synchronous motor according to the first modification. FIG. 10 is a diagram showing the fourth embodiment, and is a perspective view of a rotor 20 of a synchronous motor according to a second modification. It is a figure which shows Embodiment 4, and is a perspective view (a) and front sectional drawing (b) of the rotor 20 of the synchronous motor of the modification 3. FIG. It is a figure which shows Embodiment 4, and is the perspective view (a) and front view (b) of the rotor 20 of the synchronous motor of the modification 4. FIG. FIG. 10 is a diagram illustrating the fifth embodiment and illustrating the compressor 11;

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Rotor core, 2 Magnet insertion hole, 3 Rotary shaft fitting hole, 4 Permanent magnet, 5 Non-magnetic material area | region, 6 Outer magnetic body area | region, 7 Slit hole, 7a Slit hole, 7b Slit hole, 7c Slit hole, 7d Slit hole, 8 nonmagnetic space, 8a nonmagnetic space, 8b nonmagnetic space, 8c nonmagnetic space, 8d nonmagnetic space, 9 induced voltage waveform, 10 induced voltage waveform, 11 compressor, 12 synchronous motor, 13 compression mechanism section , 14 Refrigerant piping, 20 Synchronous motor rotor, 29 Cogging torque waveform, 30 Cogging torque waveform.

Claims (11)

A rotor core that is formed by laminating electromagnetic steel plates and has a magnet insertion hole along the outer periphery,
A permanent magnet inserted into the magnet insertion hole and constituting a magnetic pole;
An outer peripheral magnetic body region formed between an outer peripheral edge of the rotor core and the permanent magnet;
A non-magnetic region between the outer peripheral edge of the rotor core and the permanent magnet so that the area of the outer peripheral magnetic region is small near the magnetic pole and gradually increases toward the center of the magnetic pole. The rotor of the synchronous motor characterized by forming. A rotor core that is formed by laminating electromagnetic steel plates and has a magnet insertion hole along the outer periphery,
A permanent magnet inserted into the magnet insertion hole and constituting a magnetic pole;
An outer peripheral magnetic body region formed between an outer peripheral edge of the rotor core and the permanent magnet;
The rotor core between the outer peripheral edge of the rotor core and the permanent magnet so that the area of the outer peripheral magnetic region is small near the magnetic pole and gradually increases toward the center of the magnetic pole. A rotor of a synchronous motor, wherein a non-magnetic region is formed at an axial end of the synchronous motor. A rotor core that is formed by laminating electromagnetic steel plates and has a magnet insertion hole along the outer periphery,
A permanent magnet inserted into the magnet insertion hole and constituting a magnetic pole;
An outer peripheral magnetic body region formed between an outer peripheral edge of the rotor core and the permanent magnet;
The rotor core between the outer peripheral edge of the rotor core and the permanent magnet so that the area of the outer peripheral magnetic region is small near the magnetic pole and gradually increases toward the center of the magnetic pole. A rotor of a synchronous motor, wherein a non-magnetic region is formed at a substantially central portion in the axial direction of the motor.   3. The synchronous motor rotor according to claim 2, wherein the non-magnetic region is divided at both ends in the axial direction of the rotor core and is disposed on a diagonal line of the permanent magnet.   The non-magnetic region is formed in a substantially triangular shape, one side of the triangular shape is arranged in the vicinity between the magnetic poles and substantially parallel to the magnetic poles, and the other side is on an end surface in the axial direction of the rotor core. 5. The synchronous motor rotor according to claim 4, wherein the rotors substantially coincide with each other.   The non-magnetic region is formed in a substantially triangular shape, one side of the triangular shape is arranged in the vicinity between the magnetic poles and substantially parallel between the magnetic poles, and the other side is a substantially axial center of the rotor core. The synchronous motor rotor according to claim 4, wherein the synchronous motor rotor is arranged in a circumferential direction at the portion.   The synchronous motor rotor according to claim 1, wherein the circumferential length of the non-magnetic region is changed stepwise in the axial direction.   The synchronous motor rotor according to any one of claims 1 to 6, wherein the non-magnetic region is configured by a plurality of slit holes that are opened in an axial direction and have different axial lengths.   The synchronous motor rotor according to any one of claims 1 to 6, wherein the non-magnetic region is configured by a plurality of non-magnetic spaces having different axial lengths.   The synchronous motor rotor according to claim 1, wherein the shape of the permanent magnet is matched with the shape of the outer peripheral magnetic body region.   A compressor equipped with a synchronous motor using the rotor of the synchronous motor according to claim 1.

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