JP2021087232A - Rotor of rotary electric machine - Google Patents

Abstract

To provide a rotor of a rotary electric machine, capable of easily balancing rotation while being capable of firmly fixing a magnetic steel sheet structuring a rotor core.SOLUTION: In a rotor core 21, permanent magnet insertion holes 25 and 26 extended in a shaft direction are formed in each magnet pole, in which permanent magnets 27 and 28 are inserted into the permanent magnet insertion holes 25 and 26. A die-casting hole extended in the shaft direction is formed between the adjacent magnetic poles in the rotor core 21, and a magnetic steel sheet 22 is fixed by a pure aluminum filled into the die-casting hole. On both end surfaces in the shaft direction of the rotor core 21, nipping parts 24a and 24b by the pure aluminum are integrally formed. Each of the nipping parts 24a and 24b includes: a thickness part 42 coupled to a rod-like part 39 by the pure aluminum filled into the die-casting hole; and a thin part 43 formed in a plurality of portions in a peripheral direction. In the thin part 43, a pin 44 for balancing rotation is integrally formed so as to be projected to an outer side in the shaft direction.SELECTED DRAWING: Figure 9

Description

The present invention relates to a rotor of a rotary electric machine.

The rotor of a permanent magnet rotating electric machine disclosed in Patent Document 1 has a wedge-shaped groove or hole, a permanent magnet mounted in the groove or hole, and a filler. The wedge-shaped groove or hole has a tapered surface whose width gradually decreases outward in the radial direction and is formed along the axial direction of the rotor core. The filler is filled in the groove or hole provided adjacent to the groove or hole for mounting the permanent magnet so as to press the permanent magnet by die casting, and is permanently filled in the space between the permanent magnet and the rotor core. Both ends of the magnet in the circumferential direction are pressed.

Japanese Unexamined Patent Publication No. 7-312837

By the way, in the rotor of a rotary electric machine, a shaft is inserted into the center of a rotor core formed by laminating electromagnetic steel plates. For example, the shaft and the rotor core are shrink-fitted and fastened, and the electromagnetic steel plate buckles due to the stress. Warpage may occur. This warp causes a decrease in the fastening force of the shaft / rotor core. Further, when rotating at high speed, the rotor deformation is further increased, which may lead to deterioration of the rotation balance.

Further, since the rotor of the rotary electric machine rotates at high speed, it is desired that the rotation can be easily balanced.
An object of the present invention is to provide a rotor of a rotary electric machine capable of firmly fixing an electromagnetic steel plate constituting a rotor core and easily balancing rotation.

The rotor of the rotary electric machine for solving the above problems is a rotor of the rotary electric machine arranged so that the outer peripheral surfaces of the cylindrical rotor cores face each other on the inner peripheral side of the stator wound with the coil, and the rotor core is , A shaft is inserted in the center of the rotor core, a permanent magnet insertion hole extending in the axial direction is formed for each magnetic pole, and the permanent magnet is inserted into the permanent magnet insertion hole. In the rotor core, a filling hole extending in the axial direction is formed between adjacent magnetic poles or in the magnetic pole, and the electromagnetic steel plate is fixed by a non-magnetic metal or resin filled in the filling hole, and the electromagnetic steel plate is fixed to both end surfaces in the axial direction of the rotor core. , The sandwiched portion made of the non-magnetic metal or resin is integrally molded, and the sandwiched portion is formed at a plurality of locations in the circumferential direction with a thick portion connected to a rod-shaped portion made of the non-magnetic metal or resin filled in the filling hole. The gist is that the thin-walled portion has a formed thin-walled portion, and the pin for balancing rotation in the thin-walled portion is integrally molded so as to project outward in the axial direction.

According to this, the electromagnetic steel sheet is fixed by the non-magnetic metal or resin filled in the filling holes extending in the axial direction between the adjacent magnetic poles or in the magnetic poles in the rotor core. By connecting to the rod-shaped part made of non-magnetic metal or resin filled in the filling hole in the thick part of the sandwiched part made of non-magnetic metal or resin, the connection strength of the rod-shaped part made of non-magnetic metal or resin is improved. Therefore, the electromagnetic steel plate constituting the rotor core can be firmly fixed. Further, since the pin for balancing the rotation is integrally molded so as to protrude outward in the axial direction in the thin-walled portion formed at a plurality of positions in the sandwiching portion, the rotation can be easily balanced by using this pin. ..

Further, in the rotor of a rotary electric machine, a lid member in which only the filling hole is formed is arranged between the electromagnetic steel plate in which the permanent magnet insertion hole and the filling hole are formed in the rotor core and the holding portion. It is good to be there.

In this case, it is possible to prevent the non-magnetic metal or resin filled in the filling hole from flowing into the permanent magnet insertion hole.
Further, in the rotor of the rotary electric machine, the permanent magnet insertion holes extend in the axial direction and are arranged on the outer side in the radial direction, and the permanent magnet insertion holes on the outer diameter side extend in the axial direction. It includes an inner diameter side permanent magnet insertion hole arranged on the inner diameter side of the hole, an outer diameter side permanent magnet is inserted into the outer diameter side permanent magnet insertion hole, and an inner diameter side permanent magnet is inserted into the inner diameter side permanent magnet insertion hole. Is inserted, and a flux barrier is continuously formed on the outer side in the circumferential direction of the inner diameter side permanent magnet insertion hole in the rotor core, and the filling hole is formed in a region sandwiched by the flux barrier between adjacent magnetic poles in the rotor core. It is preferable that it is formed so as to extend in the axial direction.

Further, in the rotor of the rotary electric machine, the outer diameter side permanent magnet insertion hole and the inner diameter side permanent magnet insertion hole at each of the magnetic poles may have an arc shape.
It is particularly useful when the outer diameter side permanent magnet insertion hole and the inner diameter side permanent magnet insertion hole form an arc shape.

Further, in the rotor of the rotary electric machine, a filling hole extending in the axial direction is further formed so as to be separated from the outside in the circumferential direction of the flux barrier in the rotor core, and the electromagnetic steel sheet is formed by the non-magnetic metal or resin filled in the filling hole. It should be fixed.

In this case, the electromagnetic steel sheet constituting the rotor core can be fixed more firmly.

According to the present invention, the electromagnetic steel sheets constituting the rotor core can be firmly fixed and the rotation can be easily balanced.

The schematic diagram of the rotary electric machine in an embodiment. A perspective view of the rotor and the shaft. An exploded perspective view of the rotor and shaft. Front view of rotor and shaft. FIG. 4 is a cross-sectional view taken along the line AA of FIG. Perspective view of the rotor and shaft in vertical section. FIG. 3 is a perspective view of a rotor core and a shaft without a holding portion and a lid member. The perspective view of the rotor core and the shaft in the vertical section without the holding part and the lid member. A perspective view in a state where a part of the rotor and the shaft is broken (a partially broken view of FIG. 2). Side view of rotor and shaft (arrow view B in FIG. 4). FIG. 2 is a perspective view showing a molded product by aluminum die casting in FIG. Sectional view of another example rotor.

Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings.
As shown in FIG. 1, the rotary electric machine 10 is a permanent magnet embedded type synchronous motor, and includes a rotor (rotor) 20 and a stator (stator) 100. The stator 100 is arranged on the outer peripheral side of the cylindrical rotor 20. The inner peripheral surface of the stator 100 faces the outer peripheral surface of the rotor 20 via a gap. All of the figures are schematic views, and the shapes are emphasized. The rotary electric machine 10 has a number of poles of "4", and permanent magnets are arranged at 90 ° intervals in the circumferential direction.

As shown in FIG. 1, in the stator 100, the stator core 101 has a cylindrical shape, and a plurality of slots 102 are formed inside the stator core 101 in the circumferential direction. Each slot 102 is open to the inner peripheral surface. Teeth 103 are formed between the slots 102. A coil (winding) 104 is wound around the tooth 103. As described above, the stator 100 has a configuration in which the teeth 103 around which the coil 104 is wound are arranged side by side in the circumferential direction and the coil 104 is wound around the stator 100.

A rotor 20 is arranged inside the stator 100, and the rotor 20 includes a cylindrical rotor core 21 in which a plurality of (for example, several tens) substantially disk-shaped electromagnetic steel sheets 22 are laminated. In the rotor core 21, laminated electromagnetic steel sheets 22 are connected by dowel caulking. As shown in FIG. 2, the rotor 20 has lid members 23a and 23b arranged at both ends in the axial direction of the laminated electromagnetic steel plates 22 and lid members 23a and 23b so as to sandwich the laminated electromagnetic steel plates 22. It has holding portions 24a and 24b by aluminum die casting arranged on the outer side in the axial direction of the above.

As shown in FIG. 1, the rotor 20 is rotatably supported by a bearing of a housing (not shown) via a shaft 50 in a state where the outer peripheral surface of the rotor core 21 is spaced apart from the teeth 103 at a predetermined distance. In this way, the rotor 20 is arranged on the inner peripheral side of the stator 100 so that the outer peripheral surfaces of the rotor core 21 face each other with a gap.

As shown in FIGS. 2, 4, and 7, the shaft 50 is inserted into the center of the rotor core 21 formed by laminating the electromagnetic steel sheets 22. The rotor core 21 is fitted and fastened to the shaft 50 by shrink fitting (or press fitting or the like). As shown in FIG. 5, the rotor core 21 has an outer diameter side permanent magnet insertion hole 25, an inner diameter side permanent magnet insertion hole 26, flux barriers 29, 30, 37, 38, and die casting holes 31, 33, 35.

As shown in FIGS. 5, 7, and 8, the rotor core 21 has an outer diameter side permanent magnet insertion hole 25 extending in the axial direction and arranged radially outside, and an outer diameter side permanent magnet extending in the axial direction. An inner diameter side permanent magnet insertion hole 26 arranged on the inner diameter side of the insertion hole 25 is formed for each magnetic pole. The outer diameter side permanent magnet insertion hole 25 and the inner diameter side permanent magnet insertion hole 26 at each magnetic pole have an arc shape. Specifically, as shown in FIG. 5, the outer diameter side permanent magnet insertion hole 25 and the inner diameter side permanent magnet insertion hole 26 have an arc shape with the center side of the rotor core 21 convex (centered on the outer diameter side of the rotor core 21). Is doing.

As shown in FIG. 6, the outer diameter side permanent magnet 27 is inserted into the outer diameter side permanent magnet insertion hole 25, and the inner diameter side permanent magnet 28 is inserted into the inner diameter side permanent magnet insertion hole 26. The outer diameter side permanent magnet 27 is adhesively fixed to the outer diameter side permanent magnet insertion hole 25. The inner diameter side permanent magnet 28 is adhesively fixed to the inner diameter side permanent magnet insertion hole 26.

As shown in FIG. 6, the outer diameter side permanent magnets 27 are arranged in a state of being divided in the axial direction. The inner diameter side permanent magnets 28 are arranged in a state of being divided in the axial direction. By using permanent magnets divided in the axial direction, loss can be reduced and economic efficiency can be improved.

As shown in FIG. 5, each of the embedded permanent magnets 27 and 28 has an arc shape. The permanent magnet 27 is located on the d-axis, and the permanent magnet 27 is magnetized in the thickness direction. The permanent magnet 28 is located on the d-axis, and the permanent magnet 28 is magnetized in the thickness direction. The permanent magnets 27 and the permanent magnets 28 arranged in adjacent regions (one pole) are arranged so that the outer peripheral sides of the rotor 20 have different poles. For example, when a certain permanent magnet 27 is arranged so that the teeth 103 side has an S pole, the permanent magnet 27 arranged in the adjacent region (one pole) is arranged so that the teeth 103 side has an north pole. ..

As shown in FIGS. 5 and 7, a flux barrier 29 is continuously formed on the outer side of one of the inner diameter side permanent magnet insertion holes 26 in the rotor core 21 in the circumferential direction. Further, a flux barrier 30 is continuously formed on the outer side of the other peripheral direction of the inner diameter side permanent magnet insertion hole 26 in the rotor core 21. The flux barriers 29 and 30 have an arc shape.

A die-cast hole 31 as a filling hole extending in the axial direction is formed in a region sandwiched between the flux barriers 29 and 30 between adjacent magnetic poles in the rotor core 21. The die-cast hole 31 is filled with pure aluminum 32 as a non-magnetic metal. The electromagnetic steel sheet 22 is fixed by the pure aluminum 32 filled in the die-cast hole 31. The pure aluminum 32 filled in the die-cast hole 31 is made of aluminum die-cast as shown in FIGS. 4, 5 and 6 from the state shown in FIGS. 7 and 8. As shown in FIGS. 9, 10 and 11, the rod-shaped portion 39 is formed of pure aluminum 32 filled in the die-cast hole 31.

As shown in FIGS. 5 and 7, a die-cast hole 33 is formed as a filling hole extending in the axial direction at a distance outward from the circumferential direction of the flux barrier 29 in the rotor core 21. Further, a die-cast hole 35 is formed as a filling hole extending in the axial direction separated from the outside of the flux barrier 30 in the circumferential direction of the rotor core 21. The die-cast hole 33 is filled with pure aluminum 34 as a non-magnetic metal. The die-cast hole 35 is filled with pure aluminum 36 as a non-magnetic metal. The electromagnetic steel sheet 22 is fixed by the pure aluminum 34, 36 filled in the die-cast holes 33, 35. The pure aluminum 34, 36 filled in the die-cast holes 33, 35 is made of aluminum die-cast as shown in FIGS. 4, 5 and 6 from the state shown in FIGS. 7 and 8. As shown in FIGS. 9, 10 and 11, the rod-shaped portion 40 is formed of the pure aluminum 34 filled in the die-cast hole 33, and the rod-shaped portion 41 is formed of the pure aluminum 36 filled in the die-cast hole 35. ing.

Flux barriers 37 and 38 (see FIG. 5) are continuously formed on the outer side of the outer diameter side permanent magnet insertion hole 25 in the rotor core 21 in the circumferential direction. The flux barriers 37 and 38 have an arc shape.

As shown in FIGS. 4 and 6, the rotor core 21 has holding portions 24a and 24b on both sides thereof. The sandwiching portions 24a and 24b are made of pure aluminum and are formed by aluminum die casting as shown in FIGS. 4 and 6 from the state shown in FIGS. 7 and 8. As described above, as shown in FIGS. 9, 10 and 11, the holding portions 24a and 24b made of pure aluminum are integrally molded on both end faces in the axial direction of the rotor core 21, and the holding portions 24a and 24b are shown in the drawings. 7. It is formed by aluminum die casting as shown in FIGS. 4 and 6 from the state shown in FIG.

As shown in FIGS. 9, 10 and 11, the sandwiching portions 24a and 24b are formed at a plurality of locations in the circumferential direction with the thick portion 42 connected to the rod-shaped portion 39 made of pure aluminum 32 filled in the die casting hole 31. It has a thin-walled portion 43 formed. In FIG. 10, thin-walled portions 43 are formed at a total of eight locations at 45 ° intervals in the circumferential direction. Each thin-walled portion 43 is composed of a bottom surface of a semi-circular notch in which the outer peripheral side of the sandwiching portions 24a and 24b opens. At the central portion of the thin-walled portion 43, a pin 44 for balancing rotation is integrally molded so as to project outward in the axial direction. The pin 44 has a columnar shape. A ring-shaped washer Wa (see FIG. 2) having a desired thickness as a balance weight is inserted into the pin 44, and the washer Wa can be fixed by crushing a portion of the pin 44 that protrudes outward from the washer Wa. ..

In the relationship between the number of poles and the number of pins 44 (the number of thin-walled portions 43), the number of pins is 8 for 4 poles, but 12 pins for 4 poles may be used.
As shown in FIGS. 2, 3, 4, and 6, between the electromagnetic steel sheets 22 on which the permanent magnet insertion holes 25, 26 and the die casting holes 31, 33, 35 are formed in the rotor core 21, and the sandwiching portions 24a, 24b. The lid members 23a and 23b in which the outer diameter side permanent magnet insertion hole 25 and the inner diameter side permanent magnet insertion hole 26 are not formed and only the die casting holes 31, 33 and 35 are formed are arranged. Aluminum can be injected into the die-cast holes 31, 33, and 35 by an aluminum die-cast as shown in FIGS. 4, 5, and 6 from the state shown in FIGS. 7 and 8.

Next, the operation of the rotary electric machine 10 configured in this way will be described.
When the rotary electric machine is driven, a current is supplied to the coil 104 of the stator 100 to generate a rotating magnetic field in the stator 100, and the rotating magnetic field acts on the rotor 20. Then, the rotor 20 rotates in synchronization with the rotating magnetic field due to the magnetic attraction and repulsion between the rotating magnetic field and the permanent magnets 27 and 28.

The die-cast hole 31 extends in the axial direction in the region sandwiched between the flux barriers 29 and 30 between the adjacent magnetic poles in the rotor core 21, and the electromagnetic steel plate 22 is fixed by the pure aluminum 32 filled in the die-cast hole 31. .. As a result, the electromagnetic steel sheet 22 constituting the rotor core 21 is firmly fixed, and the warp of the electromagnetic steel sheet 22 constituting the rotor core 21 is suppressed. In other words, in the substantially inverted arc-shaped two-layer magnet arrangement rotor cross-sectional shape, both performance and strength are achieved by arranging die-cast holes between the magnetic poles that are sandwiched between the flux barriers and are not affected by the shrink fitting fastening force. A rotor structure is realized.

Since the sandwiching portions 24a and 24b are reinforced at the thick portion 42 by the pure aluminum 32 filled in the die casting hole 31 with the rod-shaped portion 39, the electromagnetic steel plate 22 can be firmly fixed. Since the pins 44 for balancing the rotation are projected outward in the axial direction in the thin-walled portions 43 formed at a plurality of positions in the sandwiching portions 24a and 24b, the rotation can be easily balanced. In this way, the thick portion 42 of the holding portions 24a and 24b made of pure aluminum is connected to the rod-shaped portion 39 made of pure aluminum 32 filled in the die-cast hole 31, so that the connection strength of the rod-shaped portion 39 made of pure aluminum is formed. Is improved. Further, since the pin 44 for balancing the rotation is projected outward in the axial direction in the thin portion 43 of the holding portions 24a and 24b, the rotation balance of the rotor can be balanced.

The details will be described below.
The length of the permanent magnet insertion hole on the inner diameter side tends to increase, and the balance between performance and strength is insufficient. Specifically, the electromagnetic steel sheet tends to turn up due to centrifugal force, and when bending stress is applied to the thin-walled bridge, the strength becomes stronger. The drop is large. In this case, adding a thick non-magnetic end plate to the end of the rotor as a measure against the strength of the rotor core causes an increase in cost. That is, when the permanent magnets are arranged in two layers on the outer diameter side and the inner diameter side, the fitting fastening force between the rotor core and the shaft is reduced due to the internal stress due to the shrink fitting of the shaft, which warps in the direction perpendicular to the cross section. When a rigid end plate is arranged and fixed on the rotor end face in order to suppress this warpage, the manufacturing cost increases due to the cost increase due to the rigid end plate and the fixing means (screws, caulking, etc.).

In this embodiment, die casting technology and equipment are used when the induction motor manufacturing equipment can be used. The fixing means by aluminum die casting has a structure that can be constructed at low cost by minimizing new capital investment when the equipment for manufacturing the induction motor is already owned. Further, by die-casting, a rigid end plate and end plate fixing means are not required, and the cost of parts can be reduced.

A general aluminum die cast uses a strong and robust material such as ADC12, but in order to construct it inexpensively without requiring additional capital investment, it is made of pure aluminum, which is the same material used for manufacturing induction motors. It is configured.

Here, when pure aluminum is used to improve the rigidity of the rotor structure, it is important to arrange the die-cast holes that communicate with the rotor core cross section. Even though it is a synchronous motor, if the die-cast hole is arranged at an inappropriate position due to the alternating magnetic field from the stator, an induced current may be generated, which may adversely affect the performance such as output reduction. Therefore, it is necessary to carefully consider the effect of arranging the die-cast holes near the outer periphery of the cross section of the rotor core, and the rotor core and shaft are shrink-fitted and fixed to reduce costs, and the die-cast holes are arranged on the inner peripheral side. If it is installed, it may adversely affect the strength such as a decrease in shrinkage fastening force. That is, in the rotor of an electric motor in which a permanent magnet is embedded in the rotor core, a die-cast hole cannot be formed because the vicinity of the permanent magnet is a magnetic path, and the inner diameter side of the rotor core is a region used for shrink fitting. Therefore, it is not possible to form a die-cast hole.

In the present embodiment, the die-cast hole 31 is formed in the region sandwiched between the flux barriers 29 and 30 between the adjacent magnetic poles, which is a portion closer to the inner diameter between the magnetic poles, and the q-axis magnetic flux constituting the magnetic circuit of the rotor core is formed. It does not interfere with the shrink fit fastening strength of the shaft on the inner diameter side. The formation position of the die-cast hole is preferably a place that does not obstruct the q-axis magnetic path between the magnetic poles, that is, a place where the magnetic flux density in the rotor core is not high, and after the left and right magnetic flux branches in the q-axis magnetic flux from the outer diameter side to the inner diameter side. It is a place between. As a result, the q-axis magnetic flux of the rotor core is not hindered, and the shrink fit of the shaft on the inner diameter side is not hindered.

In this way, even when the shaft is shrink-fitted into the rotor core, the fastening strength between the rotor and the shaft can be sufficiently improved. When manufacturing the rotor 20, the electromagnetic steel sheets 22 are laminated and arranged, and one lid member 23a is laminated and arranged on one end surface of the electromagnetic steel sheet laminated body. Then, after inserting the permanent magnets 27 and 28 and further arranging the other lid member 23b, they are fixed by caulking and fixed by die casting with pure aluminum 32, 34, 36 in the die casting holes 31, 33, 35.

Therefore, the electrical steel sheet is easily warped by shrink fitting during manufacturing and is easily warped by the centrifugal force when the rotation speed is increased during normal operation, but in the present embodiment, the warpage of the electrical steel sheet can be suppressed.

Further, in the holding portions 24a and 24b, the parts requiring strength are thickened and the parts where the strength is not so strong are thinned to form pins 44, and the holding parts 24a and 24b are die-cast with pure aluminum equivalent to the induction motor. And the pin 44 is formed. At this time, a thin-walled portion 43 is formed in which the pin 44 is arranged at a position avoiding the rod-shaped portion 39 formed by the aluminum die-cast penetrating in the axial direction. In this case, the manufacturing equipment of the induction motor can be used, and while the rotor structure is inexpensive and the manufacturing cost is low, the size can be reduced by the amount of thinning the axial length (ΔL in FIG. 4).

Regarding the positional relationship between the rod-shaped portion 39 and the thin-walled portion 43 by the aluminum die casting, the arrangement of the die casting holes needs to be optimized from the viewpoint of strength and performance. It is connected to the thick portions 42 of the holding portions 24a and 24b arranged on both sides in the axial direction, and firmly fixes the rotor core 21.

Further, the sandwiching portions 24a and 24b have both a function as a strength portion for suppressing the warp of the rotor core and a function for balancing the rotation of the rotor, and the die casting structure is made of pure aluminum so that the production line of the induction motor can be diverted. Therefore, the washer Wa can be caulked and fixed to the pins 44 formed on the holding portions 24a and 24b, so that the rotation can be balanced at low cost.

By the way, during high-speed rotation, hoop stress is distributed in the holding portions 24a and 24b, and the stress is concentrated in the connecting portion between the holding portions 24a and 24b and the rod-shaped portion 39, particularly in the inner peripheral side corner portion thereof, so that stress relaxation is performed. In order to do this, it is necessary to secure a certain thickness of the connecting portion in terms of strength. Lid members 23a and 23b are arranged at the connection portion between the holding portions 24a and 24b and the rod-shaped portion 39, and since the lid members 23a and 23b do not have permanent magnet insertion holes, electromagnetic steel having permanent magnet insertion holes is provided in terms of strength. It is more advantageous than the steel sheet, and the lid members 23a and 23b made of the electromagnetic steel sheet can be manufactured by laminating at the same time at low cost by switching the punching press type cutting tool of the electromagnetic steel sheet. Therefore, the strength of the connecting portion can be reinforced by the lid members 23a and 23b arranged at the connecting portion between the holding portions 24a and 24b and the rod-shaped portion 39. Further, the lid members 23a and 23b also have a function of preventing pure aluminum from flowing into the permanent magnet insertion holes. Moreover, the sandwiching portions 24a and 24b can be made thin in the portion where the connecting portion of the rod-shaped portion 39 is not arranged, and by making this portion thin and arranging the pin 44, the size is small while ensuring the strength. Can be realized.

As shown in FIG. 10, a part of the connecting portion of the holding portions 24a and 24b with the rod-shaped portions 40 and 41 is located in the thin-walled portion 43, but this is because the rod-shaped portions 40 and 41 are from the rod-shaped portion 39. Is also located on the outer peripheral side, and the hoop stress is reduced by that amount, and there is no problem in strength at the portion where the thin-walled portion and the connecting portion coincide with each other.

In this way, the end portions of the rotor core 21 are provided with lid members 23a and 23b arranged at both ends in the axial direction in order to protect the permanent magnets from the molten die casting while reinforcing the die casting strength. Regarding the axial wall thickness of the sandwiching portions 24a and 24b, the portion where the die-casting hole 31 is arranged is thick, the other portion is thin, and the thin-walled portion 43 is provided with a pin 44 for rotational balance. By arranging, compared to the case of using the method of drilling holes in a flat surface (weight reduction method) as a method of balancing rotation, the method of crushing the pin protrusion after inserting the washer into the pin 44 made of pure aluminum (washer increase amount). By using the method), it is possible to obtain a rotor having small and tough die-casting holding portions 24a and 24b by arranging pins and thin-walled portions while providing a low-cost rotation balance correcting means. Further, by using the lid members 23a and 23b having high strength (without permanent magnet insertion holes), the strength of the connecting portion between the holding portions 24a and 24b where the stress is concentrated and the rod-shaped portion 39 can be reinforced.

According to the above embodiment, the following effects can be obtained.
(1) As a configuration of the rotor 20 of the rotary electric machine 10 arranged so that the outer peripheral surfaces of the cylindrical rotor core 21 face each other on the inner peripheral side of the stator 100 around which the coil 104 is wound, the rotor core 21 is made of an electromagnetic steel plate 22. It is constructed by laminating, and the shaft 50 is inserted in the center. Permanent magnet insertion holes 25 and 26 extending in the axial direction are formed for each magnetic pole in the rotor core 21, and permanent magnets 27 and 28 are inserted into the permanent magnet insertion holes 25 and 26. A die-cast hole 31 as a filling hole extending in the axial direction is formed between adjacent magnetic poles in the rotor core 21, and the electromagnetic steel plate 22 is fixed by the pure aluminum 32 as a non-magnetic metal filled in the die-cast hole 31. Holding portions 24a and 24b made of pure aluminum as a non-magnetic metal are integrally molded on both end faces in the axial direction of the rotor core 21. The sandwiching portions 24a and 24b include a thick-walled portion 42 connected to a rod-shaped portion 39 made of pure aluminum filled in the die-cast hole 31, and a thin-walled portion 43 formed at a plurality of locations in the circumferential direction. In the thin portion 43, the pin 44 for balancing the rotation is integrally molded so as to project outward in the axial direction.

Therefore, the electromagnetic steel sheet 22 is fixed by the pure aluminum 32 filled in the die-cast holes 31 extending in the axial direction between the adjacent magnetic poles in the rotor core 21. By connecting the thick portion 42 of the holding portions 24a and 24b made of pure aluminum to the rod-shaped portion 39 made of pure aluminum filled in the die-cast hole 31, the connection strength of the rod-shaped portion 39 made of pure aluminum can be improved. , The electromagnetic steel plate 22 constituting the rotor core 21 can be firmly fixed. Further, since the pins 44 for balancing the rotation are integrally molded so as to project outward in the axial direction in the thin-walled portions 43 formed at a plurality of positions in the sandwiching portions 24a and 24b, the pins 44 can be easily rotated by using the pins 44. Can be balanced. Further, the thin-walled portion 43 having the pin 44 extending in the axial direction can be miniaturized in the axial direction by the amount thinner than the thick-walled portion 42 (ΔL in FIG. 4).

(2) The lid member 23a, in which only the die-cast holes are formed between the electromagnetic steel sheets 22 in which the permanent magnet insertion holes 25 and 26 and the die-cast holes 31 as the filling holes are formed in the rotor core 21 and the sandwiching portions 24a and 24b. Since the 23b is arranged, it is possible to prevent the pure aluminum filled in the die casting hole from flowing into the permanent magnet insertion hole.

(3) The permanent magnet insertion holes extend in the axial direction and are arranged on the outer side in the radial direction, and the permanent magnet insertion holes 25 on the outer diameter side and extend in the axial direction and are arranged on the inner diameter side of the permanent magnet insertion holes 25 on the outer diameter side. The outer diameter side permanent magnet 27 is inserted into the outer diameter side permanent magnet insertion hole 25, and the inner diameter side permanent magnet 28 is inserted into the inner diameter side permanent magnet insertion hole 26, including the inner diameter side permanent magnet insertion hole 26. Flux barriers 29 and 30 are continuously formed on the outer side of the inner diameter side permanent magnet insertion hole 26 in the rotor core 21 in the circumferential direction, and the die cast hole 31 is a region sandwiched between the flux barriers 29 and 30 between adjacent magnetic poles in the rotor core 21. It is formed so as to extend in the axial direction. In this case, it is suitable.

(4) The outer diameter side permanent magnet insertion hole 25 and the inner diameter side permanent magnet insertion hole 26 at each magnetic pole form an arc shape. It is particularly useful when the outer diameter side permanent magnet insertion hole 25 and the inner diameter side permanent magnet insertion hole 26 form an arc shape.

(5) Die-cast holes 33, 35 as filling holes extending in the axial direction separated from the outside of the flux barriers 29, 30 in the rotor core 21 in the circumferential direction are further formed, and as a non-magnetic metal filled in the die-cast holes 33, 35. The electromagnetic steel plate 22 is fixed by the pure aluminum 34 and 36 of the above. In this case, the electromagnetic steel sheet 22 constituting the rotor core 21 can be further firmly fixed, and the warpage of the electromagnetic steel sheet 22 constituting the rotor core 21 can be further suppressed.

The embodiment is not limited to the above, and may be embodied as follows, for example.
○ The non-magnetic metal was pure aluminum, but it is not limited to this. As the non-magnetic metal, an aluminum alloy such as ADC12 or copper may be used. Further, a resin may be used in addition to the non-magnetic metal, and the resin may be molded.

That is, by using the above-mentioned die-cast hole 31 as a resin mold hole and the above-mentioned pure aluminum 32 as a resin, a filling hole extending in the axial direction is formed between adjacent magnetic poles in the rotor core 21, and the filling hole is filled. The electromagnetic steel plate 22 is fixed by the resin. Further, by using the above-mentioned die-cast holes 33 and 35 as resin mold holes and the above-mentioned pure aluminum 34 and 36 as resin, the flux barriers 29 and 30 in the rotor core 21 are separated from each other in the circumferential direction and extend in the axial direction. The filling holes are further formed, and the electromagnetic steel plate 22 is fixed by the resin filled in the filling holes.

○ The die-cast holes 33 and 35 may be omitted, and for example, a flux barrier may be used instead. Specifically, as shown in FIG. 12 instead of FIG. 5, if the strength is not affected, the die casting holes 33 and 35 are abolished, and the flux barriers 60 and 61 continuously extending from the permanent magnet insertion holes 26 are used. By forming it, a structure without a bridge can be formed, and it is designed to improve the performance. Furthermore, since there are no rod-shaped portions 40 and 41, the thin-walled portions at the holding portions 24a and 24b can be further expanded and the amount of aluminum is also increased. Can be reduced.

○ The number of poles is not limited to 4 poles. It may be more or less than 4 poles.
○ The permanent magnet may be V-shaped instead of arc-shaped.
○ The rotor core 21 is formed with an outer diameter side permanent magnet insertion hole 25 and an inner diameter side permanent magnet insertion hole 26, and the outer diameter side permanent magnet 27 is inserted into the outer diameter side permanent magnet insertion hole 25 and the inner diameter side is permanent. The permanent magnet 28 on the inner diameter side was inserted into the magnet insertion hole 26, but the structure is not limited to this, and the permanent magnet insertion hole and the permanent magnet are not arranged in two layers in the radial direction. A structure in which magnets are arranged over one layer in the radial direction may be used. In short, the rotor core 21 may have a permanent magnet insertion hole extending in the axial direction for each magnetic pole, and the permanent magnet may be inserted into the permanent magnet insertion hole.

○ In the rotor core 21, a die-cast hole 31 as a filling hole extending in the axial direction was formed between adjacent magnetic poles, but instead of this, a die-cast hole or a resin mold as a filling hole extending in the magnetic pole in the rotor core 21 in the axial direction was formed. Holes may be formed. For example, in the case of a structure in which a permanent magnet insertion hole and a permanent magnet are arranged over one layer in the radial direction, a die-cast hole or a resin mold hole as a filling hole is formed in a space on the inner diameter side of the permanent magnet insertion hole and the permanent magnet.

○ The motor may be other than a synchronous motor, in short, it may be a permanent magnet embedded motor.

10 ... Rotating electric machine, 20 ... Rotor, 21 ... Rotor core, 22 ... Electromagnetic steel plate, 23a ... Lid member, 23b ... Lid member, 24a ... Holding part, 24b ... Holding part, 25 ... Permanent magnet insertion hole on the outer diameter side, 26 ... Inner diameter side permanent magnet insertion hole, 27 ... Outer diameter side permanent magnet, 28 ... Inner diameter side permanent magnet, 29, 30 ... Flux barrier, 31 ... Die cast hole, 32 ... Pure aluminum, 33 ... Die cast hole, 34 ... Pure aluminum, 35 ... Die cast hole, 36 ... Pure aluminum, 39 ... Rod-shaped part, 42 ... Thick part, 43 ... Thin part, 44 ... Pin, 50 ... Shaft, 100 ... Stator, 104 ... Coil.

Claims (5)

A rotor of a rotary electric machine arranged so that the outer peripheral surfaces of a cylindrical rotor core face each other on the inner peripheral side of a stator wound with a coil.
The rotor core is formed by laminating electromagnetic steel sheets, and a shaft is inserted in the center.
Permanent magnet insertion holes extending in the axial direction are formed in the rotor core for each magnetic pole.
A permanent magnet is inserted into the permanent magnet insertion hole,
In the rotor core, a filling hole extending in the axial direction is formed between adjacent magnetic poles or in the magnetic pole, and the electromagnetic steel sheet is fixed by the non-magnetic metal or resin filled in the filling hole.
The holding portions made of the non-magnetic metal or resin are integrally molded on both end faces in the axial direction of the rotor core.
The sandwiching portion is
It has a thick portion connected to a rod-shaped portion made of non-magnetic metal or resin filled in the filling hole, and a thin portion formed at a plurality of locations in the circumferential direction.
A rotor of a rotary electric machine, characterized in that a pin for balancing rotation in the thin-walled portion is integrally molded so as to project outward in the axial direction. The claim is characterized in that a lid member in which only the filling hole is formed is arranged between the electromagnetic steel sheet in which the permanent magnet insertion hole and the filling hole are formed in the rotor core and the sandwiching portion. The rotor of the rotary electric machine according to 1. The permanent magnet insertion holes extend in the axial direction and are arranged radially outside, and the permanent magnet insertion holes extend in the axial direction and are arranged on the inner diameter side of the outer diameter side permanent magnet insertion holes. Includes a permanent magnet insertion hole on the inner diameter side
The outer diameter side permanent magnet is inserted into the outer diameter side permanent magnet insertion hole, and the inner diameter side permanent magnet is inserted into the inner diameter side permanent magnet insertion hole.
A flux barrier is continuously formed on the outer side of the inner diameter side permanent magnet insertion hole in the rotor core in the circumferential direction.
The rotor of a rotary electric machine according to claim 1 or 2, wherein the filling hole is formed so as to extend in the axial direction in a region sandwiched between the magnetic poles adjacent to each other in the rotor core. The rotor of a rotary electric machine according to claim 3, wherein the outer diameter side permanent magnet insertion hole and the inner diameter side permanent magnet insertion hole in each of the magnetic poles have an arc shape. A feature of the rotor core is that a filling hole extending in the axial direction is further formed apart from the outside of the flux barrier in the circumferential direction, and the electromagnetic steel sheet is fixed by a non-magnetic metal or resin filled in the filling hole. The rotor of the rotary electric machine according to claim 4.

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