JP6888514B2 - Rotating machine rotor - Google Patents

Description

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

Conventionally, as a rotor of a rotary electric machine, there is one described in Patent Document 1. The rotor includes a shaft and an annular rotor core, the rotor core being fixed to the outer peripheral surface of the shaft. The rotor core includes a plurality of permanent magnets embedded and arranged at intervals in the circumferential direction. Further, the rotor core has a refrigerant passage extending in the axial direction, and a cooling medium such as cooling oil flows in the refrigerant passage. When using a rotary electric machine, the permanent magnet generates heat due to the eddy current flowing inside it, which causes the rotor core to heat up. This rotary electric machine cools the rotor core by flowing a cooling medium in the refrigerant passage.

Japanese Unexamined Patent Publication No. 2017-046545

If the rotor core is provided with a refrigerant passage, the strength of the portion around the refrigerant passage in the rotor core is reduced. Therefore, when the rotor rotates at high speed, the centrifugal force generated in the rotor core increases, so that the peripheral portion of the refrigerant passage is easily deformed.

Therefore, an object of the present invention is to provide a rotor of a rotary electric machine capable of cooling a rotor core and suppressing deformation of a portion around a refrigerant passage.

In order to solve the above problems, the rotor of the rotary electric machine according to the present invention includes a shaft and a rotor core including an electromagnetic steel plate fixed and laminated on the outer peripheral surface of the shaft, and the rotor core includes a cooling medium. A bottomed refrigerant passage extending from one side to the other in the axial direction is provided, and an inner refrigerant passage provided inside the refrigerant passage and having a longer passage than the refrigerant passage is defined in the refrigerant passage. The inner refrigerant passage has two or more axially extending passages extending in the axial direction, and two axially extending passages at the bottom end of the refrigerant passage in the axial direction. at least look including a communicating passage portion communicating the extension passage, the refrigerant passage, a cylindrical hole portion, 2 or more attachment recesses extending radially from the cylindrical hole portion communicating with the cylindrical hole The partition wall has a shape corresponding to the two or more mounting recesses and has two or more ends that fit into the two or more mounting recesses .

According to the rotor according to the present invention, a partition wall is provided inside the refrigerant passage. Therefore, the strength of the portion around the refrigerant passage can be increased at this partition wall portion, and the deformation of the refrigerant passage can be suppressed.

It is a partial plan view of a part in the circumferential direction in the rotor of the rotary electric machine which concerns on one Embodiment of this invention. It is sectional drawing of the line AA of FIG. It is a partial cross-sectional view when the rotor is cut in a plane including a radial direction and a circumferential direction while passing through a refrigerant passage extending in the axial direction. It is sectional drawing around the refrigerant passage extending in the axial direction and one side in the axial direction when the rotor is cut in the plane passing through the center in the thickness direction of a plate-shaped partition wall member. It is sectional drawing corresponding to FIG. 3 in the rotor of the 1st modification. It is sectional drawing corresponding to FIG. 3 in the rotor of the 2nd modification. It is sectional drawing corresponding to FIG. 3 in the rotor of the 3rd modification. It is sectional drawing corresponding to FIG. 3 in the rotor of the 4th modification. It is a cross section corresponding to FIG. 4 in the rotor of the 5th modification. It is a side view of the partition wall member in the rotor of the 6th modification.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. When a plurality of embodiments and modifications are included in the following, it is assumed from the beginning that a new embodiment is constructed by appropriately combining the characteristic portions thereof. Further, in the following description and drawings, the R direction indicates the radial direction of the rotor 10 of the rotary electric machine 1, the θ direction indicates the circumferential direction of the rotor 10, and the Z direction indicates the axial direction of the rotor 10. The R, θ, and Z directions are orthogonal to each other.

FIG. 1 is a partial plan view of a part of the rotor 10 of the rotary electric machine 1 according to the embodiment of the present invention in the θ direction, and FIG. 2 is a sectional view taken along line AA of FIG. In FIG. 1, the refrigerant passage 70 is shown by a solid line in order to clearly show the arrangement position of the refrigerant passage 70 provided inside the rotor 10.

As shown in FIGS. 1 and 2, the rotor 10 includes a shaft 30 and a rotor core 50. The shaft 30 has a cylindrical through hole 31 extending in the Z direction along the central axis. The rotor core 50 is fixed to the outer peripheral surface of the shaft 30 so as not to rotate relative to each other by means such as key engagement, spline engagement, shrink fitting, or cold fitting. The rotor core 50 is a cylindrical magnetic material concentric with the shaft 30. The rotor core 50 includes a plurality of annular steel plates laminated in the Z direction. The annular steel plate is formed by punching, for example, a thin plate-shaped electromagnetic steel plate with a press. Insulating coatings are provided on the front and back surfaces of each electrical steel sheet before punching. This insulating coating is provided to increase the interlayer resistance of the electrical steel sheet, and is provided to prevent an interlayer eddy current. By preventing the interlayer eddy current, iron loss (energy loss generated in the conversion of electrical energy to magnetic energy) can be reduced and energy efficiency can be improved. The plurality of laminated annular steel sheets are connected by being subjected to a treatment such as pressure caulking.

As shown in FIG. 1, the rotor core 50 has a plurality of magnet insertion hole pairs 51, 52 extending in the Z direction. Each magnet insertion hole pair 51 is composed of two paired magnet insertion holes 51a and 51b. The magnet 55 is inserted into the magnet insertion holes 51a and 51b over substantially the entire length except for both ends of the holes. The magnet insertion holes 51a and 51b into which the magnet 55 is inserted are filled with a resin such as an epoxy resin, for example. The magnet 55 is fixed in the magnet insertion holes 51a and 51b by the resin. Similarly, each magnet insertion hole pair 52 is also composed of two paired magnet insertion holes 52a and 52b. The magnet 58 is inserted into the magnet insertion holes 52a and 52b over substantially the entire length except for both ends of the holes. The magnet insertion holes 52a and 52b into which the magnet 58 is inserted are also filled with a resin such as an epoxy resin. The magnet 58 is fixed in the magnet insertion holes 52a and 52b by the resin.

A pair of magnetic poles is formed by two magnets 55 inserted into the magnet insertion hole pair 51 and two magnets 58 inserted into the magnet insertion hole pair 52. Due to the formation of such magnetic poles, the north pole and the south pole are alternately formed in the θ direction in the rotor 10.

Although not described in detail, the rotary electric machine 1 includes an annular stator (not shown) on the outer peripheral side of the rotor 10. The stator includes an annular yoke and a plurality of teeth, the plurality of teeth are arranged at intervals in the θ direction, and each tooth projects inward in the R direction from the yoke. Each tooth faces the rotor 10 in the R direction through a slight gap. A stator coil is wound around the teeth.

When the rotary electric machine 1 is used as a motor, a rotating magnetic field is generated in the stator by energizing the stator coil. An electromagnetic force is applied to the rotor 10 having magnets 55 and 58 by this rotating magnetic field to rotate the rotor 10. On the other hand, when the rotary electric machine 1 is used as a generator, an induced current is generated in the stator coil by the fluctuating magnetic field generated by the magnets 55 and 58 of the rotating rotor 10, and this induced current is taken out as electric power.

As shown in FIG. 2, the rotor 10 has a refrigerant passage 70. The refrigerant passage 70 is provided to allow a cooling medium made of a liquid such as cooling oil to flow from the inside to the outside in the R direction. The refrigerant passage 70 includes a first radial extending passage portion 71, a second radial extending passage portion 72, a first axial extending passage portion 73, a circumferential extending passage portion 74, and a second axial extending passage. A portion 75 and a third radial extending passage portion 76 are included.

The first radial extension passage portion 71 extends substantially in the R direction and extends from the inner peripheral surface 33 of the shaft 30 to the outer peripheral surface 34. Further, the second radial extending passage portion 72 communicates with the end portion of the first radial extending passage portion 71 on the outer side in the R direction, and extends outward from the inner peripheral surface 53 of the rotor core 50 in the R direction. .. Further, the first axial extending passage portion 73 communicates with the end portion of the second radial extending passage portion 72 on the outer side in the R direction, and is located on one side in the Z direction (lower side on the paper surface) from the end portion. It is postponed. Further, the circumferential extending passage portion 74 communicates with the end portion on one side in the Z direction of the extending passage portion 73 in the first axial direction, and extends from the end portion on one side in the θ direction.

FIG. 3 is a partial cross-sectional view of the rotor 10 when it passes through the extending passage portion 73 in the first axial direction and is cut in a plane including the R direction and the θ direction. As shown in FIG. 3, the first axial extending passage portion 73 is formed by internally fitting and fixing a partition wall member 90 extending in the Z direction into a bottomed cylindrical hole 80 provided in the rotor core 50. Will be done. The partition member 90 is an example of the partition portion. The partition member 90 is a plate-shaped member, and the end surfaces 91 and 92 on both sides of the partition member 90 in the R direction are arc surfaces having a shape corresponding to the inner peripheral surface of the cylindrical hole 80. The partition member 90 passes through the central axis of the cylindrical hole 80, and the end faces 91 and 92 of the partition member 90 are 2 on the inner peripheral surface of the cylindrical hole 80 facing the center of the cylindrical hole 80 in the radial direction. It abuts at locations 81 and 82 without gaps. The partition wall member 90 is fixed to the cylindrical hole 80 so as not to move relative to the cylindrical hole 80 by means such as shrink fitting or cold fitting. The partition member 90 divides the inner region of the cylindrical hole 80 into two regions having substantially the same area in the cross-sectional view shown in FIG. One of the two plane regions is included in the first axial extending passage portion 73, and the other is included in the second axial extending passage portion 75.

FIG. 4 is a cross-sectional view of the periphery of the cylindrical hole 80 and one side in the Z direction when the rotor 10 is cut on a plane passing through the center of the partition wall member 90 in the thickness direction. As shown in FIG. 4, the end surface 91 on one side of the partition wall member 90 in the Z direction faces the bottom surface 84 of the cylindrical hole 80 in the Z direction through a gap, and as a result, the circumferential extending passage portion 74 is formed in the cylindrical hole. It is provided on one side of the 80 in the Z direction. The circumferential extension passage portion 74 extends in the θ direction. The length of the circumferential extending passage portion 74 substantially matches the thickness of the partition wall member 90.

Again, referring to FIG. 2, the second axial extending passage portion 75 communicates with one end of the circumferential extending passage portion 74 in the θ direction, and from that end to the other side in the Z direction (FIG. 2). Extends to the upper side of the paper. Further, the third radial extending passage portion 76 communicates with the end portion of the second axial extending passage portion 75 on the other side in the Z direction, and extends outward in the R direction from the end portion to the outer peripheral surface of the rotor core 50. It is postponed. The cylindrical hole 80 is provided in the rotor core 50 and constitutes a refrigerant passage extending in the Z direction, and includes a first axial extending passage portion 73, a circumferential extending passage portion 74, and a second axial extending passage portion. Reference numeral 75 constitutes an inner refrigerant passage 79. The inner refrigerant passage 79 has a flow path length that is approximately twice the flow path length of the cylindrical hole 80. The inner refrigerant passage 79 is formed in the cylindrical hole 80 by fitting and fixing the partition member 90 inwardly on the inner surface of the cylindrical hole 80.

The partition member 90 is made of a material having an insulating property, and current does not flow between the electromagnetic steel plates adjacent to each other in the Z direction through the partition member 90. Therefore, even if the partition member 90 is inserted, it is possible to prevent the iron loss from becoming large. As the insulating material constituting the partition wall member 90, the ceramics shown in [Table 1] and the plastic (resin) shown in [Table 2] can be preferably used.

Other suitable insulating materials constituting the partition member 90 include marble, diamond, mica, dry wood and the like. Alternatively, the partition wall member 90 does not have to be formed only of the insulating material, and may be formed by subjecting the surface of a conductive material such as metal to an insulating treatment. As the heat insulating treatment, the insulating coating of the materials described in [Table 1] and [Table 2] and the sticking to the surface of an insulating sheet, for example, a conductive material such as paper, rubber, or vinyl are preferably adopted. it can.

In the above configuration, the cooling medium is supplied to the through hole 31 of the shaft 30 from a refrigerant supply source (not shown) provided outside the rotary electric machine 1 and including a pump or the like. A part of the cooling medium supplied to the through hole 31 is introduced into the refrigerant passage 70, and the inside of the refrigerant passage 70 is the first radial extending passage portion 71, the second radial extending passage portion 72, and the first. Axial extending passage 73, circumferential extending passage 74, second axial extending passage 75, and third radial extending passage 76 flow in the order shown by arrow B in FIG. , Is discharged from the third radial extending passage portion 76 of the refrigerant passage 70 into the gap between the rotor 10 and the stator. The cooling medium discharged into the gap G travels in the gap G and then falls to the bottom of the case of the rotary electric machine. On the other hand, the cooling medium introduced into the through hole 31 and not discharged into the gap is discharged to the outside from one side in the Z direction of the shaft 30 and falls to the bottom of the case. The cooling medium that has fallen to the bottom of the case is cooled at the bottom of the case or another part, and then returned to the refrigerant supply source.

According to the above embodiment, the partition member 90 is internally fitted and fixed to the inner surface of the cylindrical hole 80 provided in the rotor core 50 and extending in the Z direction. Therefore, at least a part of the inner surface of the cylindrical hole 80 is restrained by the partition member 90, and that part is less likely to be deformed. Therefore, the strength of the portion around the cylindrical hole 80 can be increased, and the insufficient strength of the rotor core 50 can be suppressed.

Further, by fitting and fixing the partition wall member 90 in the cylindrical hole 80, the inner refrigerant passage 79 having a flow path length longer than the flow path length of the cylindrical hole can be defined in the cylindrical hole 80. Therefore, the flow path area of the inner refrigerant passage 79 (the area of the cross section perpendicular to the flow path through which the refrigerant passes) can be made smaller than the flow path area of the cylindrical hole 80, and the flow velocity of the cooling medium passing through the inner refrigerant passage 79 can be adjusted. It can be faster than the flow velocity of the cooling medium passing through the cylindrical hole 80 when the partition member 90 is not inserted. Therefore, the cooling efficiency of the rotor core 50 due to the flow of the cooling medium can be increased.

The present invention is not limited to the above-described embodiment and its modifications, and various improvements and modifications can be made within the scope of the claims of the present application and the equivalent scope thereof.

For example, in the above embodiment, the partition wall member 90 has a cylindrical hole 80 in a cross section when a cylindrical hole (a refrigerant passage extending in the Z direction provided in the rotor core) 80 is cut in a plane including the θ direction and the R direction. Was divided into two regions having substantially the same area. However, as shown in FIG. 5, that is, the cross-sectional view corresponding to FIG. 3 in the rotor 110 of the first modification, when the partition member 190 as an example of the partition is cut in a plane including the θ direction and the R direction. In the cross section of the above, the refrigerant passage (hereinafter referred to as the original refrigerant passage) 180 provided in the rotor core 150 in the Z direction may be divided into three substantially the same area regions 181, 182, 183, and the original refrigerant passage may be divided. Three axially extending passage portions 185, 186, 187 may be formed in 180. In this case, for example, the end of the first axial extending passage portion 185 on one side in the Z direction and the end of the second axial extending passage portion 186 on one side in the Z direction are communicated with each other to extend in the second axial direction. The end of the existing passage portion 186 on the other side in the Z direction and the end portion of the third axial extending passage portion 187 on the other side in the Z direction are communicated with each other.

According to this modification, since the partition wall member 190 can restrain (support) three points on the inner peripheral surface of the original refrigerant passage 180, the rigidity around the original refrigerant passage 180 can be further increased. Further, the flow path length of the inner refrigerant passage 179 formed in the original refrigerant passage 180 by connecting the above-mentioned three axial extending passage portions 185, 186, 187 is abbreviated as the flow path length of the original refrigerant passage 180. It can be tripled. Therefore, the speed of the cooling medium flowing through the inner refrigerant passage 179 can be further increased, and the cooling efficiency by the cooling medium can be further increased. The original refrigerant passage may be divided into four or more substantially the same area regions in the cross section when the partition wall member is cut in a plane including the θ direction and the R direction, and the original refrigerant passage may be divided into four or more axial directions. An extended passage portion may be formed.

Further, by providing two or more mounting portions of the partition wall member in the original refrigerant passage and attaching two or more mounting portions of the partition wall member to the two or more mounting portions, the relative movement of the partition wall member with respect to the original refrigerant passage can be performed. In addition to preventing this, the effect of suppressing the deformation of the original refrigerant passage by the partition member may be increased in each stage.

For example, as shown in FIG. 6, that is, the cross-sectional view of the rotor 210 of the second modification, which corresponds to FIG. 3, the partition wall member 290 as an example of the partition wall portion has an H-shaped shape in the cross-sectional view. Well. The original refrigerant passage 280 may include a cylindrical hole 281 and two substantially T-shaped mounting recesses 282,283 communicating with the cylindrical hole 281. Then, the two mounting recesses 282, 283 having a substantially T-shaped cross section are arranged so as to face each other in the radial direction of the cylindrical hole portion 281, and both ends 291, 292 of the partition member 290 having a substantially H-shaped cross section are substantially cross-sectioned. It may be fitted tightly into the T-shaped mounting recesses 282 and 283. In this case, the portion 251 sandwiched between the cylindrical hole portion 281 and the mounting recesses 282, 283 in the rotor core 250 can be pressed against the cylindrical hole portion 281 side by both end portions 291, 292 of the partition wall member 290. Therefore, the deformation suppressing effect of the original refrigerant passage 280 by the partition member 290 can be greatly increased in each stage. The mounting recesses 282, 283 having a substantially T-shaped cross section constitute the mounting portion of the original refrigerant passage, and the both end portions 291, 292 of the partition wall member 290 fitted into the mounting recesses 282, 283 form the mounting portion of the partition wall member. To do.

Further, as shown in FIG. 7, that is, the cross-sectional view corresponding to FIG. 3 in the rotor 310 of the third modification, the mounting portion of the original refrigerant passage 380 is gradually separated from the cylindrical hole portion 381 in the radial direction. The mounting recesses 382,383 that expand toward the end may be used, and the mounted portion of the partition wall member 390 as an example of the partition wall portion is a portion 391,392 having a shape corresponding to the mounting recesses 382,383 and extends in the Z direction. It may be provided at both ends in the width direction of the existing partition member 390.

In short, in each of the two or more mounting portions provided in the original refrigerant passage, the mounted portion of the partition wall member attached to the original refrigerant passage can move relative to the rotor core only in the Z direction, and the two or more mounting portions have the original refrigerant passage. Any shape may be used as long as it can prevent the relative rotation of the partition wall member with respect to the relative rotation. In the examples shown in FIGS. 7 and 8, the case where two mounting portions are provided in the original refrigerant passage has been described, but three or more mounting portions may be provided in the original refrigerant passage, and three or more mounting portions may be provided in the original refrigerant passage. Axial extending passages may be provided.

Further, as shown in FIG. 8, that is, the cross-sectional view corresponding to FIG. 3 in the rotor 410 of the fourth modification, the partition member 490 as an example of the partition is the inner peripheral surface of the cylindrical hole 480 as the original refrigerant passage. It may have an annular portion 491 that is fitted and fixed to the inside without a gap. According to the rotor 410 of the third modification, the inner peripheral surface of the cylindrical hole 480 can be restrained (supported) over the entire circumference by the annular portion 491 of the partition member 490. Therefore, the deformation of the portion around the cylindrical hole 480 in the rotor core 450 can be effectively suppressed.

Further, in the above embodiment, as shown in FIG. 4, the two first and second axial extending passage portions 73,75 (see FIG. 3) are provided with a circumferential extending passage having a rectangular cross-sectional shape. The case of communicating in section 74 has been described. However, as shown in FIG. 9, that is, the cross-sectional view corresponding to FIG. 4 in the rotor 510 of the fifth modification, the cross-sectional shape of the flow path of the communication passage portion 574 communicating the two axial extending passage portions is. It may be circular instead of rectangular, and may have any other shape.

Further, as shown in FIG. 10, the partition wall member 690 as an example of the partition wall portion may be composed of a rod-shaped member provided with a spiral flange 691. Further, a cylindrical hole in the spiral flange 691 such that the outermost portion in the radial direction contacts the inner peripheral surface may be formed in the rotor core so as to extend in the Z direction, and the original refrigerant passage may be formed. May be. Then, by fitting the partition wall member 690 into the cylindrical hole and fixing it, a spiral inner refrigerant passage may be defined in the cylindrical hole by a flange adjacent to the inner peripheral surface of the cylindrical hole in the Z direction. According to this modification, there is no place in the inner refrigerant passage where the direction of the flow of the cooling medium changes significantly. Therefore, the cooling medium can easily flow smoothly in the inner refrigerant passage, and the flow velocity of the cooling medium can be easily increased.

Further, a case will be described in which the partition wall portion is composed of partition wall members 90,190,290,390,490,690 and internally fitted and fixed in the original refrigerant passages 180,280,380 of the rotor cores 50,150,250,450. did. However, the partition wall portion may be composed of a partition wall member, and the partition wall member may be arranged so as to be slidably contacted inside the original refrigerant passage. Alternatively, the partition wall portion may be formed integrally with the rotor core, and in this case, the partition wall portion can be easily formed by, for example, press molding.

Further, a case where the cylindrical holes 80,480 and the original refrigerant passages 180,280,380 (refrigerant passages provided in the rotor core and extending from one side in the axial direction to the other side) extend in the Z direction has been described. However, the refrigerant passage provided in the rotor core may extend in a linear direction inclined in the Z direction. Alternatively, the refrigerant passage provided in the rotor core may extend from one side in the Z direction to the other side in a curved passage. The refrigerant passage provided in the rotor core may be any passage as long as it extends from one side in the Z direction to the other side.

1 rotary electric machine, 10,110,210,310,410,510 rotor, 30 shaft, 50,150,250,450 rotor core, 79,179 inner refrigerant passage, 80,480 cylindrical hole (one side to the other side in the axial direction) Refrigerant passage extending to), 90,190,290,390,490,690 partition member, 180,280,380 original refrigerant passage (refrigerant passage extending from one side in the axial direction to the other side), radial direction of the rotor in the R direction, θ direction Rotor circumferential direction, Z direction Rotor axial direction.

Claims (1)

With the shaft
A rotor core containing an electromagnetic steel plate fixed and laminated on the outer peripheral surface of the shaft, and
With
The rotor core is provided with a bottomed refrigerant passage that flows from one side in the axial direction to the other side as the cooling medium flows.
It has a partition wall provided inside the refrigerant passage and defines an inner refrigerant passage in which the flow path is longer than the refrigerant passage in the refrigerant passage.
The inner refrigerant passage communicates two or more axially extending passages extending in the axial direction with the two axially extending passages at the axially bottom end of the refrigerant passage. at least look including a communicating passage portion,
The refrigerant passage has a cylindrical hole portion and two or more mounting recesses extending radially from the cylindrical hole portion and communicating with the cylindrical hole portion.
A rotor of a rotary electric machine, wherein the partition wall has a shape corresponding to the two or more mounting recesses and has two or more ends that fit into the two or more mounting recesses.

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