JP6156122B2 - Rotor structure of embedded magnet motor - Google Patents

Description

  The present invention relates to a rotor structure for an embedded magnet motor.

  Conventionally, in a rotor structure of a magnet-embedded motor, a plurality of electromagnetic steel plates are laminated to form a rotor core, and a plurality of magnet insertion holes are formed in the inner periphery of each electromagnetic steel plate. In addition, the high-speed magnet-embedded motor is provided with a reinforcing column such as a rib in the magnet insertion hole of each electromagnetic steel plate so that it can withstand the centrifugal force during high-speed rotation. Strength is strengthened.

  Conventionally, for example, Patent Document 1, Patent Document 2, and Patent Document 3 disclose a configuration that suppresses this because the motor performance is unbalanced due to the anisotropy of the magnetic properties of the electromagnetic steel sheet. Yes.

JP 2003-284274 A JP-A-7-99744 JP-A-7-236237

  Generally, in a high-speed magnet-embedded motor, the strength of the magnet insertion hole is increased by increasing the thickness of the reinforcing column provided in the magnet insertion hole as the maximum rotational speed increases and centrifugal force acts more strongly. It needs to be reinforced more.

  However, if a thick reinforcing column is provided in the magnet insertion hole, a part of the magnetic flux from the magnet inserted into the magnet insertion hole to the stator increases through the reinforcing column, so that the magnetic flux short circuit amount increases. It becomes a cause that cannot show the performance of the period.

  Therefore, it is desirable to make the thickness of the reinforcing column thinner than before so as to reduce the magnetic flux short circuit amount while reinforcing the strength around the magnet insertion hole of the electromagnetic steel sheet.

  Therefore, the present inventors, from the viewpoint of strength, not the magnetic steel anisotropy from the viewpoint of magnetic properties, the magnetic steel sheet has a high strength in the direction perpendicular to the rolling direction, It has been found that there is a material whose strength in the direction perpendicular to the rolling is about 10% higher than the strength in the direction of rolling.

  In view of this point, the present invention adopts a configuration in which the thickness of the reinforcing column provided in the magnet insertion hole of the electromagnetic steel sheet is set thin in the reinforcing column arranged in the direction perpendicular to the rolling direction where the strength of the electromagnetic steel sheet is high. Thus, while sufficiently reinforcing the strength around the magnet insertion hole arranged in the direction perpendicular to the rolling, the amount of magnetic flux short circuit through the reinforcing column provided in the magnet insertion hole is reduced.

  In order to achieve the above object, in the rotor structure of a magnet-embedded motor according to the first aspect of the present invention, a rotor core (30) is formed by laminating a plurality of electromagnetic steel plates (30a) rolled from a predetermined rolling direction. In the rotor structure of the magnet embedded type motor, the plurality of electromagnetic steel plates (30a) are each provided with a magnet insertion hole (at least in a portion in the rolling direction and a portion in a direction perpendicular to the rolling direction perpendicular to the rolling direction). 33R) and (33A) are formed, and the plurality of magnet insertion holes (33R) and (33A) are respectively provided with magnets (31l) and (31r) disposed in the magnet insertion holes (33R) and (33A), respectively. Reinforcing columns (34R) and (34A) that reinforce around the magnet insertion holes (33R) and (33A) by extending in the magnetic axis direction of the magnets (31l) and (31r) are formed at least at the magnetic pole center position. Among the plurality of magnet insertion hole reinforcement columns (34R), (34A), the magnet insertion hole (33A) reinforcement column (34A) in which the magnetic axis direction of the magnet is the rolling perpendicular direction is the rolling method The thickness (tA) extending in the magnet is set to be thinner than the thickness (tR) of the reinforcing column (34R) of the magnet insertion hole (33R) in which the magnetic axis direction of the magnet is the rolling direction. To do.

  In the first aspect of the invention, the portion of the magnet insertion hole in which the magnetic axis direction of the magnet is the direction perpendicular to the rolling direction of the magnetic steel sheet is higher in strength than the portion of the magnet insertion hole in the rolling direction. Even if the thickness of the reinforcing column is reduced, the strength can be sufficiently secured to the same extent as the portion of the magnet insertion hole in the rolling direction. In addition, as the thickness of the reinforcing column is reduced, the leakage magnetic flux through the reinforcing column is reduced, and the amount of magnetic flux short circuit can be reduced.

  According to a second aspect of the present invention, in the rotor structure of the magnet-embedded motor, the bridge portion (36) between two adjacent magnet insertion holes (33R), (33A) has a thick reinforcing column (34R). A portion (36R) on the magnet insertion hole (33R) side having a portion extending in the same direction as the thick reinforcing column (34R) and having a large thickness, the thin reinforcing column (34A) is formed. The magnet insertion hole (33A) side portion (36A) has a feature that it extends in the same direction as the thin reinforcing column (34A) and is thinner than the thick reinforcing column (34R). And

  In the second aspect of the present invention, since the bending stress is not applied to the bridge portion between two adjacent magnetic poles, but only the tensile stress is applied, sufficient strength is ensured. Moreover, in the bridge portion, even if the strong portion extending in the direction perpendicular to the rolling is formed thinner than the portion extending in the rolling direction, the strength at the two portions of the bridge portion can be ensured equally.

  According to a third aspect of the present invention, in the rotor structure of the magnet-embedded motor, the magnets (31l) and (31r) disposed in the magnet insertion hole (33A) having the thin reinforcing column (34A) are Compared to magnets (31l) and (31r) placed in magnet insertion holes (33R) with thick reinforcing columns (34R), the magnet width is smaller, the amount of magnetization is smaller, or the residual magnetic flux density is lower. It is composed of a magnet.

  In the third aspect of the invention, in the portion of the magnet insertion hole located in the direction perpendicular to the rolling direction, the magnetic flux short circuit amount is reduced by the thin reinforcing column, while the magnetization amount of the magnet arranged in the magnet insertion hole Alternatively, since the magnet width is set to be small or the amount of magnetic flux directed to the stator can be adjusted to be small because the magnet is configured with a low residual magnetic flux density, the portion of the magnet insertion hole located in the rolling direction is perpendicular to the rolling direction. It is possible to make the magnetic flux amounts of the magnets facing the stator substantially equal to each other between the magnet insertion hole portions positioned in the direction. Furthermore, in the case of a magnet perpendicular to the rolling direction in which the magnetic flux short circuit amount is reduced, the demagnetization due to the reverse magnetic field from the stator is strong, but if the magnet is composed of a magnet with a low residual magnetic flux density, this A magnet having a low residual magnetic flux density has a high coercive force and is strong against demagnetization, and therefore, it is possible to satisfactorily balance the demagnetization performance with the magnet in the rolling direction.

  According to a fourth aspect of the present invention, in the rotor structure of the magnet-embedded motor, the plurality of electromagnetic steel plates (30a) are stacked in a rotating stack in which the rolling direction is shifted by a predetermined angle.

  In the fourth invention, the thickness of the reinforcing pillars arranged in the magnet insertion hole is different between the rolling direction of the electromagnetic steel sheet and the direction perpendicular to the rolling direction, but the plurality of electromagnetic steel sheets constituting the rotor are shifted by a predetermined angle and stacked. Therefore, it is possible to suppress the imbalance of the magnetic flux amount due to the difference in the thickness of the reinforcing pillar.

  According to a fifth aspect of the present invention, in the rotor structure of the magnet-embedded motor, the magnets disposed in the plurality of magnet insertion holes (33R) and (33A) are injected into the magnet insertion holes (33R) and (33A) by injection molding. ).

  As described above, in the first invention, since the thickness of the reinforcing column is reduced at the portion of the magnet insertion hole located in the direction perpendicular to the rolling direction of the magnetic steel sheet and having high strength, the strength at this portion is ensured. However, it is possible to reduce the magnetic flux short-circuit amount through the reinforcing column.

  Moreover, in 2nd invention, the intensity | strength in the bridge part between both the magnetic poles of an electromagnetic steel plate can fully be ensured.

  Furthermore, in the third to fifth inventions, it is possible to suppress an imbalance in the amount of magnetic flux caused by the thickness of the reinforcing pillars arranged in the magnet insertion holes being different between the rolling direction of the magnetic steel sheet and the direction perpendicular to the rolling direction. It is.

FIG. 1 is a cross-sectional view showing a configuration of an embedded magnet motor having an embedded magnet rotor according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the magnet-embedded rotor. FIG. 3 is a plan view of one electromagnetic steel plate constituting the rotor core of the magnet embedded rotor. 4A is an enlarged sectional view around the magnet insertion hole in the rolling direction of the electromagnetic steel sheet, and FIG. 4B is an enlarged sectional view around the magnet insertion hole in the direction perpendicular to the rolling of the electromagnetic steel sheet. FIG. 5 is a plan view of one electromagnetic steel sheet showing a first modification of the embodiment. FIG. 6 is a plan view showing a main part of one electromagnetic steel sheet constituting the magnet-embedded rotor according to the second embodiment of the present invention. FIG. 7 is a plan view showing one electromagnetic steel sheet constituting the magnet-embedded rotor according to the third embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

(First embodiment)
FIG. 1 shows a cross-sectional configuration of an embedded magnet motor having an embedded magnet rotor according to the first embodiment of the present invention.

  In the figure, an embedded magnet motor (1) includes a stator (2), an embedded magnet rotor (3), and a rotating shaft (4).

  The stator (2) includes a cylindrical stator core (10) and a coil (11). The stator core (10) is formed by punching an electromagnetic steel plate by press working to create a laminated plate, and a plurality of laminated plates are arranged in the axial direction of the rotating shaft (4) (the direction of the axis (O) of the rotating shaft (4), Hereinafter, a laminated core laminated in the axial direction), and a plurality of (in the figure, six) teeth portions (six in the figure) in a rectangular parallelepiped shape extending toward the center (O) of the rotation axis on the annular back yoke portion (12). 13) and a flange portion (14) formed on the inner peripheral side of each tooth portion (13). And the said coil (11) is wound by the concentrated winding system on the outer periphery of each said teeth part (13). The flange portion (14) has an inner peripheral surface formed in a cylindrical surface, and this cylindrical surface is opposed to the outer peripheral surface of the magnet-embedded rotor (3) with a predetermined air gap (G).

  The magnet-embedded rotor (3) includes a cylindrical rotor core (30) in which the rotation shaft (4) is disposed at the center, and a rectangular magnet (31l embedded in the rotor core (30)). ), (31r). A specific configuration of the magnet embedded rotor (3) is shown in FIG.

  FIG. 2 shows an exploded perspective view of the magnet-embedded rotor (3). In the magnet-embedded rotor (3) in the figure, the rotor core (30) is configured by superposing a plurality of electromagnetic steel plates (30a) made of disk-shaped thin steel plates. Each of the electromagnetic steel plates (30a) is formed with a shaft hole (32) of the rotating shaft (4) at the center and four rectangular magnet insertion holes (33) at the edge. ) Are formed so as to penetrate through the top and bottom of the substrate. Rectangular magnets (31l) and (31r) divided into two equal parts are inserted into the four magnet insertion holes (33). The detailed configuration of these magnet insertion holes (33) will be described later.

  In FIG. 2, a lower end plate (40) that covers the lower end surface of the rotor core (30) is located below the rotor core (30). In the lower end plate (40), a shaft hole (42) of the rotation shaft (4) is formed in the central portion, like each electromagnetic steel plate (30a) of the rotor core (30). On the other hand, an upper end plate (50) covering the upper end surface of the rotor core (30) is positioned above the rotor core (30) in the axial direction. Similarly to the lower end plate (40), the upper end plate (50) is also formed with a shaft hole (52) of the rotation shaft (4) at the center. These lower end plate (40) and upper end plate (50) are each formed to be thicker than the thickness of each electromagnetic steel plate (30a) of the rotor core (30), and preferably nonmagnetic materials such as SUS, aluminum, brass, etc. Made by. The lower end plate (40) and the upper end plate (50) are formed with a plurality of screw insertion holes (40a), (50a) for balance adjustment of the magnet embedded rotor (3). Screws (40b) and (50b) are screwed into some of the holes (40a) and (50a).

(Specific configuration of electrical steel sheet)
Next, a detailed configuration of the plurality of electromagnetic steel plates (30a) constituting the rotor core (30) of the rotor (3) of the magnet-embedded motor (1) will be described with reference to FIG.

  FIG. 3 shows a specific configuration of one electromagnetic steel sheet (30a). In the figure, the rolling direction (R) of the electrical steel sheet (30a) is described as being upward from the lower side of the paper as indicated by the arrow in the figure.

  This magnetic steel sheet (30a) has magnet insertion holes (33R) and (33R) for two poles in the part in the rolling direction, and magnets for two poles are inserted in the part perpendicular to the rolling direction perpendicular to the rolling direction. Holes (33A) and (33A) are formed. Each magnet insertion hole (33R) in the rolling direction has one rib (reinforcement pillar) (34R) at the position of the magnetic pole center of one magnet in order to reinforce the strength around the magnet insertion hole (33R). Is formed extending in the magnetic axis direction of the magnet for one pole, that is, in the direction of the centrifugal force acting on the rib (34R). In addition, in order to reinforce the strength around the magnet insertion hole (33A) in each magnet insertion hole (33A) in the direction perpendicular to the rolling direction, one rib (reinforcement column) is provided at the position of the magnetic pole center of one magnet. (34A) is formed extending in the magnetic axis direction of the magnet for one pole. The magnet insertion holes (33R), (33R), (33A), (33A) for four poles are divided into two magnet insertion holes (33l), (33r) on the left and right by the ribs (34R), (34A). The magnets (31l) and (31r) shown in FIG. 1 are inserted and arranged in these magnet insertion holes (33l) and (33r) by injection molding.

  The rib (34R) formed in the two magnet insertion holes (33R) in the rolling direction is enlarged as shown in FIG. 4 (a) around the upper magnet insertion hole (33R) in FIG. The thickness is set to the thickness (tR). On the other hand, the rib (34A) formed in the two magnet insertion holes (33A) in the direction perpendicular to the rolling is shown in FIG. 4 (b) in an enlarged manner around the magnet insertion hole (33A) on the right side of FIG. The thickness is set to a thickness (tA) (tA <tR) that is thinner than the thickness (tR) of the rib (34R).

  4 (a) and 4 (b), reference numerals (35R) and (35A) denote the inner sides (rotations of the ribs (34R) and (34A) provided in the magnet insertion holes (33R) and (33A)). A magnet stopper formed on the shaft hole (32 side) of the shaft (4), and the magnets (31l) and (31r) move inside the magnet insertion holes (33R) and (33A) when the motor (1) is operated. When moving in the length direction, the magnet (31l) and (31r) are applied and stopped.

  Therefore, in the present embodiment, the magnetic steel sheet (30a) has higher strength in the direction perpendicular to the rolling direction than the rolling direction, so the rib (34A) of the magnet insertion hole (33A) provided in the portion in the direction perpendicular to the rolling direction. Even if the thickness is set to a thickness (tA) (tA <tR) that is thinner than the thickness (tR) of the rib (34R) of the magnet insertion hole (33R) provided at the site in the rolling direction, The strength around the magnet insertion hole (33A) in the direction is sufficiently secured. Moreover, the magnetic flux of the magnets (31l) and (31r) arranged in the magnet insertion holes (33A) leaks to the rotating shaft (4) side through the ribs (34A) because the thickness of the ribs (34A) is thin. The amount of magnetic flux is reduced and the magnetic flux short-circuit amount is reduced.Therefore, the amount of magnetic flux from the magnets (31l), (31r) toward the teeth (13) of the stator (2) is increased, and the magnet-embedded motor (1) Improved performance.

  In addition, the magnet insertion hole (33R) on the opposite side of the electromagnetic steel sheet (30a) to the thick rib (34R) of the magnet insertion hole (33R) provided in the rolling direction portion of the electromagnetic steel sheet (30a) ) Is also formed with a thick rib (34R), and with respect to the thin rib (34A) of the magnet insertion hole (33A) provided in the portion perpendicular to the rolling direction of the electromagnetic steel sheet (30a), Since the thin rib (34A) is also formed in the magnet insertion hole (33A) on the opposite side of the magnetic steel sheet (30a) by 180 degrees, the electromagnetic steel sheet (30a) as a whole is well balanced against rotation. .

  The thickness (tA) of the rib (34A) of the magnet insertion hole (33A) in the direction perpendicular to the rolling is smaller than the thickness (tR) of the rib (34R) of the magnet insertion hole (33R) in the rolling direction. In consideration of the strength of the electromagnetic steel sheet (30a) in the direction perpendicular to the rolling and the rate of decrease in strength at the magnet insertion hole (33A) in the direction perpendicular to the rolling with respect to the decrease in the thickness (tA) of the rib (34A). It is determined.

(Modification)
FIG. 5 shows a modification of the first embodiment.

  In the above embodiment, instead of arranging one rib (33R), (33A) provided in the magnet insertion holes (33R), (33A) at the magnetic pole center position of the magnet, this modification can be seen from FIG. As described above, three ribs are formed per one magnet insertion hole (33R) and (33A).

  Even in this case, the thickness of the rib (34R) formed in the two magnet insertion holes (33R) in the rolling direction is set to the thickness (tR), and the two magnet insertion holes (33A) in the direction perpendicular to the rolling direction. The thickness of the rib (34A) to be formed is set to a thickness (tA) (tA <tR) that is thinner than the thickness (tR) of the rib (34R).

  Therefore, also in this modification, while sufficiently securing the strength around the magnet insertion holes (33A) in the direction perpendicular to the rolling, the magnetic flux short-circuit amount through the thin ribs (34A) is reduced, and these magnet insertion holes Since the amount of magnetic flux from the magnet arranged at (33A) toward the teeth portion (13) of the stator (2) can be increased, the performance of the magnet-embedded motor (1) can be improved.

(Second Embodiment)
Subsequently, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 6 shows a plan view around the magnet insertion hole (33R) in the rolling direction of the electromagnetic steel sheet (30a). In the present embodiment, in the bridge portion (36) where the magnet insertion hole (33R) in the rolling direction and the magnet insertion hole (33A) in the direction perpendicular to the rolling are adjacent to each other, the portion (36R) on the magnet insertion hole (33R) side in the rolling direction ) Is the same direction as the extending direction of the rib (34R) of the magnet insertion hole (33R) in the rolling direction (the direction in which centrifugal force acts, and the direction indicated by the arrow (G) in the figure), that is, in parallel. ). The thickness of this part (36R) is set to the same thickness as the thick rib (34R) of the magnet insertion hole (33R) in the rolling direction. On the other hand, the portion (36A) on the side of the magnet insertion hole (33A) in the direction perpendicular to rolling extends in the same direction as the direction in which the rib (34A) of the magnet insertion hole (33A) in the direction perpendicular to rolling extends (that is, parallel). At the same time, the thickness of the portion (36A) is set to the same thickness as the thin rib (34A) of the magnet insertion hole (33A) in the direction perpendicular to the rolling.

  Therefore, in the present embodiment, in the bridge portion (36), the extending direction of the portion (36R) on the magnet insertion hole (33R) side in the rolling direction is the rib (34R) of the magnet insertion hole (33R) in the rolling direction. The direction in which the portion (36A) on the side of the magnet insertion hole (33A) in the direction perpendicular to the rolling extends is the rib of the magnet insertion hole (33A) in the direction perpendicular to the rolling. Since it is set in parallel with the direction (34A) extending (34A), the two parts (36R) and (36A) of this bridge part (36) are not subjected to bending stress, only tensile stress. Therefore, sufficient strength is ensured.

  Moreover, in the bridge portion (36), the portion (36A) on the magnet insertion hole (33A) side in the direction perpendicular to the rolling extends in the direction perpendicular to the rolling, and its strength is higher than the strength in the rolling direction. Even if the portion (36A) on the magnet insertion hole (33A) side is formed narrower than the portion (36R) on the magnet insertion hole (33R) side in the rolling direction, sufficient strength is ensured.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.

  FIG. 7 exemplifies one of a plurality of electromagnetic steel sheets (30a) constituting the rotor core of the four-pole embedded magnet motor of the present embodiment. In the figure, the width (WMA) of two magnets (33l) and (33r) inserted into the magnet insertion hole (33A) in the direction perpendicular to the rolling is set to the two magnets inserted into the magnet insertion hole (33R) in the rolling direction. The width is set smaller than the width (WMR) of the magnets (33l) and (33r) (WMA <WMR). Other configurations are the same as those in the first embodiment.

  Accordingly, in the present embodiment, a thin rib (thickness of the magnet insertion hole (33A) in the direction perpendicular to the rolling is reduced with respect to the magnetic flux short circuit amount through the thick rib (34R) of the magnet insertion hole (33R) in the rolling direction ( While the magnetic flux short-circuit amount through 34A) is reduced, the magnetic flux amount of the small width (WMA) magnets (31l) and (31r) arranged in the magnet insertion hole (33A) in the direction perpendicular to the rolling direction is inserted in the magnet in the rolling direction. Since the magnetic flux amount of the magnets (31l) and (31r) having a large width (WMR) arranged in the hole (33R) is reduced, the rolling of the electrical steel sheet (30a) is performed as in the second embodiment. Between the direction of rotation and the direction perpendicular to the rolling direction, the amount of magnetic flux from the magnets (31l), (31r) arranged in the magnet insertion holes (33R), (33A) toward the teeth part (13) of the stator (2) The magnetic flux unbalance between the rolling direction and the perpendicular direction of rolling of the electromagnetic steel sheet (30a) can be effectively suppressed.

  In this embodiment, the width (WMA) of the magnets (33l) and (33r) of the magnet insertion holes (33A) in the direction perpendicular to the rolling is set to be narrow, and the rolling direction and the direction perpendicular to the rolling direction of the electrical steel sheet (30a) are set. In other cases, for example, the magnets (31l) and (31r) placed in the magnet insertion holes (33A) in the direction perpendicular to the rolling direction are reduced in the magnetizing amount, or in the direction perpendicular to the rolling direction. The magnets (33l) and (33r) of the magnet insertion hole (33A) are composed of magnets having a low residual magnetic flux density Br, and the magnetic flux amount unbalance between the rolling direction and the perpendicular direction of rolling of the electrical steel sheet (30a) It may be suppressed.

  In the magnets (31l) and (31r) in the magnet insertion hole (33A) in the direction perpendicular to the rolling direction, the magnetic flux short circuit amount is reduced by the thin rib (34A). Strong influence of magnetism. However, the magnets (31l) and (31r) having a low residual magnetic flux density Br inserted in the magnet insertion hole (33A) in the direction perpendicular to the rolling have a high holding force and are resistant to demagnetization. The demagnetization performance can be well balanced between the magnets (31l) and (31r) of 33R).

(Other embodiments)
In the second and third embodiments, the shape of the bridge portion (36), the width of the magnet insertion hole (33A) in the direction perpendicular to the rolling, and the amount of magnetization of the magnets (31l), (31r) are changed. Although the unbalance of the magnetic flux amount between the rolling direction of the electromagnetic steel sheet (30a) and the direction perpendicular to the rolling direction was suppressed, in addition, when forming the rotor core (30) by laminating a plurality of electromagnetic steel sheets (30a), each electromagnetic Rolling of electrical steel sheets (30a) by laminating them by rotating the steel sheets (30a) with different rolling directions by a predetermined angle, for example, by laminating the rolling directions by 90 degrees with a 4-pole motor. You may suppress the imbalance of the magnetic flux amount between a direction and a rolling orthogonal direction.

  In the above description, the present invention is applied to a four-pole embedded magnet motor, but the present invention is naturally applicable to a multi-pole embedded magnet motor such as 8-pole, 12-pole, or 16-pole.

  As described above, since the present invention has set the thickness of the reinforcing column of the magnet insertion hole provided in the direction perpendicular to the rolling direction of the magnetic steel sheet thin, while ensuring the strength around the magnet insertion hole in the direction perpendicular to the rolling direction, Since the magnetic flux short-circuit amount leaking from the reinforcing column of the magnet insertion hole is reduced, the motor performance can be improved and it is useful when applied to a magnet-embedded motor.

DESCRIPTION OF SYMBOLS 1 Magnet embedded motor 2 Stator 3 Magnet embedded rotor 4 Rotating shaft 30 Rotor core 30a Laminated steel plate 31l, 31r Magnet 32 Shaft hole 33R, 33A Magnet insertion hole 34R, 34A Rib (reinforcing pillar)
36 Bridge part

Claims (5)

A rotor structure of a magnet embedded motor in which a rotor core (30) is configured by laminating a plurality of electromagnetic steel plates (30a) rolled from a predetermined rolling direction,
In each of the plurality of electromagnetic steel sheets (30a), magnet insertion holes (33R) and (33A) are formed at least in a portion in the rolling direction and a portion in the direction perpendicular to the rolling direction perpendicular to the rolling direction,
In the plurality of magnet insertion holes (33R) and (33A), the magnets are arranged at least at the magnetic pole center positions of the magnets (31l) and (31r) disposed in the magnet insertion holes (33R) and (33A), respectively. Reinforcing columns (34R) and (34A) that extend in the direction of the magnetic axis of (31l) and (31r) and reinforce around the magnet insertion holes (33R) and (33A) are formed,
Among the reinforcing columns (34R) and (34A) of the plurality of magnet insertion holes, the reinforcing column (34A) of the magnet insertion hole (33A) in which the magnetic axis direction of the magnet is the direction perpendicular to the rolling extends in the rolling direction. The magnet is characterized in that the thickness (tA) is set to be thinner than the thickness (tR) of the reinforcing column (34R) of the magnet insertion hole (33R) in which the magnetic axis direction of the magnet is the rolling direction. Embedded motor rotor structure. In the rotor structure of the magnet-embedded motor according to claim 1,
In the bridge part (36) between two adjacent magnet insertion holes (33R) and (33A),
The magnet insertion hole (33R) side portion (36R) having the thick reinforcing column (34R) extends in the same direction as the thick reinforcing column (34R) and is thick.
The magnet insertion hole (33A) side portion (36A) having the thin reinforcing column (34A) extends in the same direction as the thin reinforcing column (34A) and has the thick reinforcing column (34A). The rotor structure of a magnet-embedded motor, characterized in that it is thinner than 34R). In the rotor structure of an embedded magnet motor according to any one of claims 1 and 2,
The magnets (31l) and (31r) disposed in the magnet insertion hole (33A) having the thin reinforcing column (34A) are magnet insertion holes (33R) having the thick reinforcing column (34R). The rotor of an embedded magnet motor characterized by comprising a magnet having a smaller magnet width, a smaller amount of magnetization, or a lower residual magnetic flux density than the magnets (31l) and (31r) disposed in Construction. In the rotor structure of an embedded magnet motor according to any one of claims 1 and 2,
The rotor structure of a magnet-embedded motor, wherein the plurality of electromagnetic steel sheets (30a) are stacked by rotating stacking in which the rolling direction is shifted by a predetermined angle. In the rotor structure of a magnet-embedded motor according to any one of claims 1 to 4,
The magnet disposed in the plurality of magnet insertion holes (33R) and (33A) is disposed in each of the magnet insertion holes (33R) and (33A) by injection molding. Construction.

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