Rotor

Abstract

This suppresses uneven supply of the cooling medium at each flux barrier. [Solution] A rotor used in a motor, comprising a rotor core fixed to a rotating shaft, and a plurality of permanent magnets embedded in corresponding embedded holes at both ends of a plurality of embedded holes formed in the rotor core, forming a plurality of magnetic poles, wherein the rotor comprises a first flow path that supplies a cooling medium from one end of the rotor's axial center to the outer diameter flux barrier of the flux barriers at both ends, and a second flow path that supplies a cooling medium from the other end of the rotor's axial center to the inner diameter flux barrier of the flux barriers at both ends, and is provided so as not to merge with the first flow path.

Description

Technical Field

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[0001] The present disclosure relates to a rotor.

Background Art

[0002] Conventionally, as this type of rotor, there has been proposed a rotor including a rotor core fixed to a rotation axis, a plurality of permanent magnets embedded in embedding holes corresponding to form flux barriers at both ends of a plurality of embedding holes formed in the rotor core to form a plurality of magnetic poles, and end plates attached to both end faces in the axial direction of the rotor core (see, for example, Patent Document 1). In this rotor, a flow path for supplying a cooling medium from one end side in the axial direction of the rotor to the inner diameter side flux barrier is provided. Thereby, the refrigerant supplied to the inner diameter side flux barrier cools the permanent magnet when flowing to the outer diameter side flux barrier.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The rotor of this disclosure is A rotor used in a motor, comprising a rotor core fixed to a rotating shaft, and a plurality of permanent magnets embedded in corresponding embedded holes at both ends of a plurality of embedded holes formed in the rotor core, forming a flux barrier and a plurality of magnetic poles, wherein A first flow channel supplies a cooling medium from one end of the axial center of the rotor to the outer diameter flux barrier of the flux barriers at both ends, A second flow path is provided that supplies the cooling medium from the other end of the rotor, from the central part in the axial direction, to the flux barrier on the inner diameter side of the flux barriers at both ends, and that the flow does not merge with the first flow path. The gist of it is that it is equipped with the following features.

[0008] The rotor of this disclosure includes a first flow path that supplies a cooling medium from one end of the rotor's axial center to the outer diameter flux barrier at both ends, and a second flow path that supplies a cooling medium from the other end of the rotor's axial center to the inner diameter flux barrier at both ends, and is provided so as not to merge with the first flow path. This allows the cooling medium to be supplied to the outer diameter and inner diameter flux barriers from the first and second flow paths, respectively. As a result, uneven supply of the cooling medium to each flux barrier can be suppressed.

[0009] In the rotor of the present disclosure, a first supply hole is formed on the rotating shaft so as to open radially to the rotor and to which the cooling medium is supplied, and a second supply hole is formed on the rotating shaft so as to open radially and be at a different position from the first supply hole and to which the cooling medium is supplied, wherein the first flow path communicates with the first supply hole and at least a portion of it extends radially, and the second flow path communicates with the second supply hole and at least a portion of it extends radially. In this case, in the radially extending portions of the first and second flow paths, the cooling medium becomes thicker on the outer diameter side due to the centrifugal force accompanying the rotation of the rotor and is supplied to the flux barriers on the outer and inner diameter sides. This makes it possible to suppress uneven supply of the cooling medium to each flux barrier.

[0010] In a rotor according to the present disclosure, comprising first and second flow channels that extend at least a portion of the radial direction, the first and second supply holes may be formed in the central portion of the rotating shaft in the axial direction, the first flow channel may extend from the first supply hole in the axial direction, bend in the radial direction, and communicate with the flux barrier on the outer diameter side, and the second flow channel may extend from the second supply hole in the axial direction, bend in the radial direction, and communicate with the flux barrier on the inner diameter side, or the first supply hole may be formed on one end side of the central portion of the rotating shaft in the axial direction, the second supply hole may be formed on the other end side of the central portion of the rotating shaft in the axial direction, the first flow channel may extend from the first supply hole in the radial direction, and communicate with the flux barrier on the outer diameter side, and the second flow channel may extend from the second supply hole in the radial direction, and communicate with the flux barrier on the inner diameter side. In this way, in the radially extending portions of the first and second flow channels, the centrifugal force accompanying the rotor's rotation causes the cooling medium to thicken on the outer diameter side and supply it to the flux barriers on both the outer and inner diameter sides. This suppresses uneven supply of the cooling medium to each flux barrier.

[0011] Furthermore, the rotor of the present disclosure may also include: a first end plate disposed on one end of the rotor core in the axial direction; a second end plate disposed on the other end of the rotor core in the axial direction, paired with the first end plate and sandwiching the rotor core from both sides; a first supply hole formed in the first end plate, opening in the axial direction and communicating with the first flow path; a first receiver member attached to the first end plate on the outer diameter side of the first supply hole, standing upright outward in the axial direction from the first end plate and guiding the cooling medium sprayed onto the first end plate to the first supply hole; a second supply hole formed in the second end plate, opening in the axial direction and communicating with the second flow path; and a second receiver member attached to the second end plate on the outer diameter side of the second supply hole, standing upright outward in the axial direction from the second end plate and guiding the cooling medium sprayed onto the second end plate to the second supply hole. In this configuration, the centrifugal force generated by the rotor's rotation causes the cooling medium supplied to the first and second end plates to be received by the first and second receiver members and supplied to the first and second supply holes with a certain thickness. This prevents uneven distribution of the cooling medium at each flux barrier. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram showing the configuration of the rotor 20 in the embodiment of the present disclosure. [Figure 2] This is a schematic diagram showing the cross-sections of rotor 20 along line AA ((a)), line BB ((b)), and line CC ((c)) in Figure 1. [Figure 3] This is a schematic diagram showing the configuration of the rotor 120 in another embodiment. [Figure 4] This is a schematic diagram showing the cross-sections of rotor 120 along the EE line ((a)), the FF line ((b)), and the GG line ((c)) in Figure 3. [Figure 5] This is a schematic diagram showing the configuration of the rotor 220 in another embodiment. [Modes for carrying out the invention]

[0013] Embodiments of this disclosure will be described with reference to the drawings. Figure 1 is a schematic diagram showing the configuration of the rotor 20 of an embodiment of this disclosure. Figure 2 is a schematic diagram showing the cross-sections of the rotor 20 along line AA ((a)), line BB ((b)), and line CC ((c)) in Figure 1. Figure 1 is a schematic of the cross-section along line DD in the schematic diagram of the cross-section along line AA ((a)) in Figure 2. The rotor 20 is used, for example, as the rotor of a motor used as a driving source or generator for electric vehicles or hybrid vehicles.

[0014] The rotor 20 is rotatably positioned within a stator (not shown) via an air gap and comprises, as shown in Figures 1 and 2, a rotating shaft 22, a rotor core 24, a plurality (for example, 16 in the embodiment) of permanent magnets 28, and first and second end plates 30 and 32.

[0015] The rotating shaft 22 is hollow and has a cooling medium introduced inside. The cooling medium is stored below the motor having the rotor 20 and is supplied into the rotating shaft 22 by a pump (not shown). In the axial center of the rotating shaft 22, there are a number of (in this embodiment, for example, four) first supply holes 22h and a number of (in this embodiment, for example, four) second supply holes 23h that open radially to the rotor 20. Each of the first supply holes 22h and the second supply holes 23h is formed at a different position from one another.

[0016] The rotor core 24 is fixed to the rotating shaft 22 and is formed by stacking multiple core plates that are formed in an annular shape from electromagnetic steel sheets or the like. As shown in Figures 1 and 2, the rotor core 24 has multiple (e.g., eight in the embodiment) magnet embedding holes 29. On the inner diameter side of the flux barrier (inner diameter side flux barrier) FB2 of the rotor core 24, there are multiple (e.g., four in the embodiment) inlet grooves 24a that extend radially from each first supply hole 22h and bend axially toward the first end plate 30, and multiple (e.g., four in the embodiment) inlet grooves 24b that extend radially from each second supply hole 23h and bend axially toward the second end plate 32 and are formed so as not to merge with the inlet grooves 24a.

[0017] The permanent magnets 28 are, for example, rare-earth sintered magnets such as neodymium magnets, and are formed in a substantially rectangular parallelepiped shape. Two paired permanent magnets 28 are inserted and fixed into corresponding magnet embedding holes 29 such that the poles located on the outer circumference side of the rotor 20 are identical. Multiple magnet embedding holes 29 are arranged in the rotor core 24 in pairs at predetermined intervals (90° intervals in this embodiment) so as to penetrate the rotor core 24 in the axial direction. The paired magnet embedding holes 29 are formed so as to be spaced apart from each other as they move from the axial side of the rotor 20 toward the outer circumference (forming a substantially V shape). Each magnet embedding hole 29 has a width longer than the width of the permanent magnet 28. As a result, when the permanent magnets 28 are placed in the magnet embedding holes 29, flux barriers (outer diameter side flux barrier) FB1 and flux barriers (inner diameter side flux barrier) FB2 are formed at both ends of the magnet embedding holes 29 as gaps to suppress short circuits of magnetic flux from the permanent magnets 28.

[0018] The first end plate 30 is fixed to the rotary shaft 22 on one axial end side of the rotor core 24. The second end plate 32 is fixed to the rotary shaft 22 on the other axial end side of the rotor core 24. The first and second end plates 30 and 32 are paired to sandwich and press-fit the rotor core 24 from both sides for holding. On the rotor core 24 side of the first end plate 30, there are formed a radial groove 30g that communicates with each inflow groove 24a and extends in the radial direction, a circumferential groove 30gr that is continuous with the radial groove 30g and has a circumferential shape and overlaps and communicates with the end of each flux barrier FB1 on the first end plate 30 side, and a plurality (for example, four in the embodiment) of discharge holes 30h that communicate with the flux barrier FB2. On the rotor core 24 side of the second end plate 32, there are formed a radial groove 32g that communicates with each inflow groove 24b and extends in the radial direction, a circumferential groove 32gr that is continuous with the radial groove 32g and has a circumferential shape and overlaps and communicates with the end of each flux barrier FB2 on the second end plate 32 side, and a plurality (for example, eight in the embodiment) of discharge holes 32h that communicate with the flux barrier FB1. Each inflow groove 24a, each radial groove of 30g and the circumferential groove 30gr, and each inflow groove 24b, each radial groove 32g and the circumferential groove 32gr are formed so as not to merge.

[0019] Next, the flow of the cooling medium in the rotor 20 configured in this way will be described. In the rotor 20, the cooling medium in the rotating shaft 22 is supplied to the first and second supply holes 22h and 23h, respectively. The cooling medium supplied to the first supply hole 22h is supplied to each flux barrier FB1 through each inlet groove 24a, each radial groove 30g, and each circumferential groove 30gr due to the centrifugal force accompanying the rotation of the rotor 20, as shown by the thick solid arrows in Figures 1 and 2. In other words, each inlet groove 24a, each radial groove 30g, and each circumferential groove 30gr extends radially outward from the first supply hole 22h, bends and extends axially toward the first end plate 30, and further bends radially outward at the first end plate 30 and extends to communicate with each flux barrier FB1, forming a first flow path FP1 as a flow path for the cooling medium. The cooling medium supplied to each flux barrier FB1 is discharged outside the rotor 20 (motor) through each discharge hole 32h of the second end plate 32 and stored below the motor. The cooling medium supplied to the second supply hole 23h is supplied to each flux barrier FB2 through each inlet groove 24b, each radial groove 32g, and each circumferential groove 32gr due to the centrifugal force accompanying the rotation of the rotor 20, as shown by the thick dashed arrows in Figures 1 and 2. In other words, each inlet groove 24b, each radial groove 32g, and each circumferential groove 32gr extends radially outward from the second supply hole 23h, bends and extends axially toward the second end plate 32, and further bends radially outward at the second end plate 32 to become a second flow path FP2 that communicates with each flux barrier FB2 as a flow path for the cooling medium. The cooling medium supplied to each flux barrier FB2 is discharged outside the rotor 20 (motor) through each discharge hole 30h of the first end plate 30 and stored below the motor. The first and second flow paths FP1 and FP2 thus configured are formed so that they do not merge with each other.

[0020] Since a part (radial grooves 30g and 32g) of the first and second flow paths FP1 and FP2 is formed in the radial direction, due to the centrifugal force accompanying the rotation of the rotor 20, the cooling medium in the first and second flow paths FP1 and FP2 contacts the ends of the flux barriers FB1 and FB2 with sufficient thickness in the circumferential grooves 30gr and 32gr. Thereby, it is possible to suppress the occurrence of bias in the supply of the cooling medium in each of the flux barriers FB1 and FB2. Further, since the cooling medium is supplied from the first and second supply holes 22h and 23h to the first and second flow paths FP1 and FP2 respectively, and the cooling medium is supplied from the first flow path FP1 to the flux barrier FB1 and from the second flow path FP2 to the flux barrier FB2, the temperature difference between each permanent magnet 28 and the cooling medium becomes large, and the heat dissipation of each permanent magnet 28 can be promoted. Thereby, the permanent magnet 28 can be properly cooled.

[0021] According to the rotor 20 of the present embodiment described above, a first flow path FP1 that supplies a cooling medium from one end side from the central portion in the axial direction of the rotor 20 to the flux barrier FB1, and a second flow path FP2 that supplies a cooling medium from the other end side from the central portion in the axial direction of the rotor 20 to the flux barrier FB2 and is provided so as not to merge with the first flow path FP1 are provided, whereby it is possible to suppress the occurrence of bias in the supply of the cooling medium in each of the flux barriers FB1 and FB2.

[0022] Further, a first supply hole 22h formed in the rotary shaft 22 so as to open in the radial direction of the rotor 20 and through which the cooling medium is supplied, and a second supply hole 23h formed in the rotary shaft 22 so as to open in the radial direction and be at a position different from the first supply hole 22h and through which the cooling medium is supplied are provided. The first flow path FP1 communicates with the first supply hole 22h and at least a part thereof extends in the radial direction, and the second flow path FP2 communicates with the second supply hole 23h and at least a part thereof extends in the radial direction, whereby it is possible to suppress the occurrence of bias in the supply of the cooling medium in each of the flux barriers FB1 and FB2.

[0023] [[ID=**11**]] Furthermore, the first and second supply holes 22h and 23h are formed in the axial central part of the rotating shaft 22, and the first flow path FP1 extends axially from the first supply hole 22h, bends radially, and communicates with the flux barrier FB1, while the second flow path FP2 extends axially from the second supply hole 23h, bends radially, and communicates with the flux barrier FB2, thereby suppressing uneven supply of the cooling medium in each flux barrier FB1 and FB2.

[0024] In the embodiment described above, a plurality of first and second supply holes 22h and 23h are formed in the axial central part of the rotating shaft 22. However, the plurality of first supply holes 22h may be formed on one end side (towards the first end plate 30) from the axial central part of the rotating shaft 22, and the plurality of second supply holes 23h may be formed on one end side (towards the second end plate 32) from the axial central part of the rotating shaft 22. Figure 3 is a schematic diagram showing the configuration of the rotor 120 in another embodiment. Figure 4 is a schematic diagram showing the cross-section of the rotor 120 along the EE line ((a)), the FF line ((b)), and the GG line ((c)) in Figure 3. In this case, multiple radial grooves 130g and 132g are formed on the rotor core 24 side of the first and second end plates 30 and 32, respectively, communicating with the first and second supply holes 22h and 23h and extending radially, and each radial groove 130g and 132g is connected to the circumferential grooves 30gr and 32gr. In this way, due to the centrifugal force accompanying the rotation of the rotor 20, the cooling medium is supplied to each flux barrier FB1 and FB2 through each radial groove 130g and 132 and the circumferential grooves 30gr and 32gr. In other words, each radial groove 130g and the circumferential groove 30gr constitute a first flow path FP1 as a flow path for the cooling medium that extends radially outward from each first supply hole 22h and communicates with each flux barrier FB1. Each radial groove 132g and circumferential groove 32gr constitute a second flow path FP2 for the cooling medium, extending radially outward from each second supply hole 23h and communicating with each flux barrier FB2. In the rotor 120, the cooling medium from each radial groove 130g and 132g is supplied to the circumferential grooves 30gr and 32gr by the centrifugal force accompanying the rotation of the rotor 120. Since the centrifugal force acts radially, the cooling medium from each radial groove 130g and 132g contacts the circumferential grooves 30gr and 32gr with sufficient thickness. This suppresses uneven supply of the cooling medium in each flux barrier FB1 and FB2. Furthermore, since the cooling medium is supplied from the first and second supply holes 22h and 23h to the first and second flow paths FP1 and FP2, respectively, and the cooling medium is supplied from the first flow path FP1 to the flux barrier FB1, and from the second flow path FP2 to the flux barrier FB2, the temperature difference between each permanent magnet 28 and the cooling medium becomes large, promoting heat dissipation from each permanent magnet 28. This allows the permanent magnets 28 to be properly cooled.

[0025] In the embodiment described above, a plurality of first and second supply holes 22h and 23h are formed in the rotating shaft 22. However, the plurality of first supply holes 22h may be formed in the first and second end plates 30 and 32. Figure 5 is a schematic diagram showing the configuration of a rotor 220 in another embodiment. In the rotor 220, a plurality of first supply holes 22h are formed in the first end plate 30, opening in the axial direction of the rotor 20 and leading to a circumferential groove 30gr (first flow path FP1), and a plurality of second supply holes 23h are formed in the second end plate 32, opening in the axial direction of the rotor 20 and leading to a circumferential groove 32gr (second flow path FP2). A first receiver member 30R is attached to the first end plate 30 on the outer diameter side of the first supply holes 22h, rising outward in the axial direction from the first end plate 30. A second receiver member 32R is attached to the second end plate 32 on the outer diameter side of the second supply hole 23h, and stands axially outward from the second end plate 32. The rotor 220 then injects the cooling medium from the axially outward side of the first and second end plates 30 and 32 toward the radially inward side of the first and second receiver members 30R and 32R. As a result, the centrifugal force accompanying the rotation of the rotor 220 causes the cooling medium to be received by the first and second receiver members 30R and 32R and supplied to the first and second supply holes 22h and 23h with sufficient thickness. This suppresses uneven supply of the cooling medium in each flux barrier FB1 and FB2. Furthermore, since the cooling medium is supplied from the first and second supply holes 22h and 23h to the first and second flow paths FP1 and FP2, respectively, and the cooling medium is supplied from the first flow path FP1 to the flux barrier FB1, and from the second flow path FP2 to the flux barrier FB2, the temperature difference between each permanent magnet 28 and the cooling medium becomes large, promoting heat dissipation from each permanent magnet 28. This allows the permanent magnets 28 to be properly cooled.

[0026] In the above embodiment, the circumferential grooves 30gr and 32gr overlap with and communicate with the flux barriers FB1 and FB2. The circumferential grooves 30gr and 32gr do not have to overlap with all of the flux barriers FB1 and FB2, but may communicate with them in a way that overlaps with a portion of the ends of the flux barriers FB1 and FB2.

[0027] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be explained. In the embodiment, the rotor core 24 corresponds to the "rotor core", the permanent magnet 28 corresponds to the "permanent magnet", the first flow path FP1 corresponds to the "first flow path", and the second flow path FP2 corresponds to the "second flow path".

[0028] Furthermore, the correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem is merely an example to specifically explain the form in which the embodiment implements the invention described in the section on means for solving the problem, and does not limit the elements of the invention described in the section on means for solving the problem. In other words, the interpretation of the invention described in the section on means for solving the problem should be based on the description in that section, and the embodiment is merely one specific example of the invention described in the section on means for solving the problem.

[0029] The above describes the forms for implementing this disclosure using embodiments, but this disclosure is not limited in any way to these embodiments, and can of course be implemented in various forms without departing from the gist of this disclosure. [Industrial applicability]

[0030] This disclosure can be used in industries such as rotor manufacturing. [Explanation of symbols]

[0031] 20 Rotor, 22 Rotating shaft, 22h First supply hole, 23h Second supply hole, 24 Rotor core, 24a Inlet groove, 24b Inlet groove, 28 Permanent magnet, 29 Magnet embedding hole, 30 First end plate, 30R First receiver member, 30g Radial groove, 30gr Circumferential groove, 30h Discharge hole, 32 Second end plate, 32R Second receiver member, 32g Radial groove, 32gr Circumferential groove, 32h Discharge hole, 120 Rotor, 130g Radial groove, 132g Radial groove, 220 Rotor, FB1 Flux barrier, FB2 Flux barrier, FP1 First flow path, FP2 Second flow path.

Claims

1. A rotor used in a motor, comprising a rotor core fixed to a rotating shaft, and a plurality of permanent magnets embedded in corresponding embedded holes at both ends of a plurality of embedded holes formed in the rotor core, forming a flux barrier and a plurality of magnetic poles, wherein A first flow channel supplies a cooling medium from one end of the axial central portion of the rotor to the outer diameter flux barrier of the flux barriers at both ends, A second flow path is provided that supplies the cooling medium from the other end of the rotor, from the central part in the axial direction, to the flux barrier on the inner diameter side of the flux barriers at both ends, and that the flow does not merge with the first flow path. A rotor equipped with a rotor.

2. A rotor according to claim 1, A first supply hole is formed on the rotating shaft so as to open radially in the rotor, and the cooling medium is supplied to it. A second supply hole is formed on the rotating shaft, which opens radially and is located at a different position from the first supply hole, and through which the cooling medium is supplied. Equipped with, The first flow path communicates with the first supply hole and extends radially in at least a portion thereof. The second flow path communicates with the second supply hole and at least a portion of it extends in the radial direction. A rotor equipped with a rotor.

3. The rotor according to claim 2, The first and second supply holes are formed in the central part of the rotating shaft in the axial direction, The first flow path extends from the first supply hole in the axial direction, bends in the radial direction, and communicates with the flux barrier on the outer diameter side. The second flow path extends from the second supply hole in the axial direction, bends in the radial direction, and communicates with the flux barrier on the inner diameter side. Rotor.

4. The rotor according to claim 2, The first supply hole is formed on one end side of the central portion in the axial direction of the rotating shaft, The second supply hole is formed on the other end side of the central portion in the axial direction of the rotating shaft, The first flow path extends radially from the first supply hole and communicates with the flux barrier on the outer diameter side. The second flow path extends radially from the second supply hole and communicates with the flux barrier on the inner diameter side. Rotor.

5. A rotor according to claim 1, A first end plate positioned on the axial end side of the rotor core, A second end plate is positioned on the other end side in the axial direction of the rotor core, and is paired with the first end plate to sandwich the rotor core from both sides, A first supply hole is formed in the first end plate, opens in the axial direction and communicates with the first flow path, A first receiver member is attached to the outer diameter side of the first supply hole of the first end plate, stands upright outward in the axial direction from the first end plate, and guides the cooling medium sprayed onto the first end plate to the first supply hole. A second supply hole is formed in the second end plate, opens in the axial direction and communicates with the second flow path, A second receiver member is attached to the second end plate on the outer diameter side of the second supply hole, stands upright outward in the axial direction from the second end plate, and guides the cooling medium sprayed onto the second end plate to the second supply hole. A rotor equipped with a rotor.

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