Rotor for a rotating electric machine and rotating electric machine

Abstract

A rotor for a rotary electric machine, wherein the rotor for a rotary electric machine is provided with: a magnet; a metal sleeve composed of a metal material and disposed so as to cover the magnet; and at least one non-metal sleeve composed of a non-metal material and mounted to an outer peripheral surface of the metal sleeve, a gap being formed in the at least one non-metal sleeve so as to expose a portion of the outer peripheral surface of the metal sleeve.

Description

Technical Field

[0001] This disclosure relates to rotors for rotating electrical machines and rotating electrical machines.

[0002] This application claims priority based on Japanese Patent Application No. 2023-222324 filed with the Japan Patent Office on December 28, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] Patent Document 1 discloses an electric motor rotor, the purpose of which is to easily and efficiently mount a CFRP protective tube onto the outer peripheral surface of a permanent magnet attached to a rotor shaft. In this rotor, a permanent magnet is attached to the outer peripheral surface of the rotor shaft, and the CFRP protective tube covers the entire outer peripheral surface of the permanent magnet. A hollow chamber and a flow hole are formed on the rotor shaft, and the rotor shaft thermally shrinks by allowing liquid nitrogen or the like to flow through it. With the rotor shaft shrinking and its diameter decreasing, the protective tube is embedded into the rotor shaft and positioned on the outer peripheral side of the permanent magnet.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-50925 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] However, in rotors for rotating electrical machines, when a metal sleeve is provided to cover the magnet in order to suppress the scattering of the magnet in the event of magnet breakage, the metal sleeve has the advantage of high strength from the viewpoint of suppressing magnet scattering. On the other hand, it is prone to heating and expansion due to eddy currents. When the metal sleeve expands due to heating, a gap is generated on the inner side of the metal sleeve, which may increase the vibration of the rotor when the rotor rotates.

[0009] In view of the above, the object of at least one embodiment of the present disclosure is to provide a rotor for a rotary electric motor and a rotary electric motor that can suppress the scattering of magnets by utilizing a metal sleeve and suppress the increase in rotor vibration caused by the thermal expansion of the metal sleeve.

[0010] Technical methods for solving technical problems

[0011] To achieve the above objectives, a rotor for a rotary electric motor according to at least one embodiment of the present disclosure includes: a magnet; a metal sleeve made of a metal material, disposed to cover the magnet; and at least one non-metallic sleeve made of a non-metallic material, mounted on the outer peripheral surface of the metal sleeve, wherein a gap is formed in the at least one non-metallic sleeve such that the outer peripheral surface of the metal sleeve is partially exposed.

[0012] Invention Effects

[0013] According to at least one embodiment of the present disclosure, a rotor for a rotary electric motor and a rotary electric motor are provided, which can suppress the scattering of magnets by using a metal sleeve and can suppress the increase in rotor vibration caused by the thermal expansion of the metal sleeve. Attached Figure Description

[0014] Figure 1 This is a schematic cross-sectional view of a portion of an electric motor 2 according to one embodiment of the rotary electric motor of this disclosure.

[0015] Figure 2 It means Figure 1 A schematic cross-sectional view of the flow of cooling gas in the section shown.

[0016] Figure 3 This is a schematic cross-sectional view showing a portion of the electric motor 2 in another embodiment.

[0017] Figure 4 This is a schematic cross-sectional view showing a portion of the electric motor 2 in another embodiment.

[0018] Figure 5 This is a schematic cross-sectional view used to illustrate an example of a magnet 14 divided along the axial direction.

[0019] Figure 6 It means that it can be applied. Figures 1-4 A schematic diagram of an example of the general structure of the steam compressor 50 of the electric motor 2 shown. Detailed Implementation

[0020] Hereinafter, several embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the constituent components described as embodiments or shown in the drawings are not intended to limit the scope of the invention, but are merely illustrative examples.

[0021] For example, expressions such as "in a certain direction," "along a certain direction," "parallel," "orthogonal," "center," "concentric," or "coaxial" indicate a relative or absolute configuration, which not only strictly indicate such a configuration, but also indicate a state of relative displacement by an angle or distance with tolerance or to the extent that the same function can be obtained.

[0022] For example, terms like "same," "equal," and "homogeneous" indicate that things are equal, not only that they are strictly equal, but also that there is a difference in degree or tolerance that allows them to achieve the same function.

[0023] For example, the representation of shapes such as quadrilaterals and cylinders not only represents shapes in the strict geometric sense, but also includes shapes with concave and convex parts, chamfered parts, etc., within the range where the same effect can be achieved.

[0024] On the other hand, expressions such as "having," "possessing," "having," "including," or "having" a constituent element are not expressions of exclusivity that exclude the existence of other constituent elements.

[0025] Figure 1 This is a schematic cross-sectional view of a portion of an electric motor 2 according to one embodiment of the rotary electric motor of this disclosure.

[0026] like Figure 1 As shown, the electric motor 2 includes a rotor 4, a bearing assembly 8 that supports the rotor 4 so that it can rotate, and a stator 10.

[0027] The rotor 4 includes a shaft 12, a magnet 14, end rings 15 and 16, a metal sleeve 18, and a CFRP sleeve 20 as a non-metallic sleeve.

[0028] In the following description, unless otherwise specified, "axial" refers to the axial direction of rotor 4 (i.e., the axial direction of each of shaft 12, magnet 14, end rings 15 and 16, metal sleeve 18, and CFRP sleeve 20), "radial" refers to the radial direction of rotor 4 (i.e., the radial direction of each of shaft 12, magnet 14, end rings 15 and 16, metal sleeve 18, and CFRP sleeve 20), and "circumferential" refers to the circumferential direction of rotor 4 (i.e., the circumferential direction of each of shaft 12, magnet 14, end rings 15 and 16, metal sleeve 18, and CFRP sleeve 20).

[0029] Shaft 12 is made of metal and extends along the rotation axis O of rotor 4.

[0030] Magnet 14, for example, is made of a permanent magnet and is mounted on the outer peripheral surface 12a of shaft 12. In the illustrated example, magnet 14 has a cylindrical shape and is arranged in concentric circles relative to shaft 12, with inner peripheral surface 14a of magnet 14 fixed to outer peripheral surface 12a of shaft 12.

[0031] End ring 15 is mounted on one end of magnet 14 in the axial direction to the outer peripheral surface 12a of shaft 12, and end ring 16 is mounted on the other end of magnet 14 in the axial direction to the outer peripheral surface 12a of shaft 12. In the illustrated example, end rings 15 and 16 are respectively arranged on concentric circles relative to shaft 12, and the inner peripheral surface 15a of end ring 15 and the inner peripheral surface 16a of end ring 16 are fixed to the outer peripheral surface 12a of shaft 12.

[0032] The metal sleeve 18, made of a metal material such as heat-resistant steel, is mounted on the outer peripheral surface 14b of the magnet 14. The metal sleeve 18 has a cylindrical shape and is arranged concentrically relative to the shaft 12. The inner peripheral surface 18a of the metal sleeve 18 is fixed to the outer peripheral surface 14b of the magnet 14. In the illustrated example, the metal sleeve 18 is arranged to cover the outer peripheral surface 15b of the end ring 15, the outer peripheral surface 14b of the magnet 14, and the outer peripheral surface 16b of the end ring 16.

[0033] The CFRP sleeve 20 is made of carbon fiber reinforced plastic (CFRP) and is mounted on the outer peripheral surface 18b of the metal sleeve 18. The CFRP sleeve 20 has a cylindrical shape and is arranged concentrically relative to the shaft 12. The inner peripheral surface 20a of the CFRP sleeve 20 is fixed to the outer peripheral surface 18b of the metal sleeve 18.

[0034] In the CFRP sleeve 20, a plurality of gaps 24 are formed such that the outer peripheral surface 18b of the metal sleeve 18 is partially exposed. That is, the CFRP sleeve 20 has a plurality of gaps 24 such that when each of the gaps 24 is viewed radially from the outer side, the outer peripheral surface 18b of the metal sleeve 18 can be seen through each of the gaps 24. In the illustrated example of the outer peripheral surface 18b of the metal sleeve 18, the plurality of gaps 24 are radially penetrating through the CFRP sleeve 20, and the plurality of gaps 24 are formed at different locations in the axial direction. Furthermore, in the illustrated example, the plurality of gaps 24 are formed over a portion of the circumferential direction.

[0035] Here, the effect of the rotor 4 of the aforementioned electric motor 2 will be explained.

[0036] According to the rotor 4 described above, the scattering of the magnet 14 in the event of magnet 14 breakage can be suppressed by the metal sleeve 18 covering the magnet 14. In addition, by installing a CFRP sleeve 20 on the outer peripheral surface 18b of the metal sleeve 18, the thermal expansion of the metal sleeve 18 can be suppressed by the CFRP sleeve 20.

[0037] Here, if a CFRP sleeve 20 with a lower thermal conductivity than the metal sleeve 18 is installed on the outer peripheral surface 18b of the metal sleeve 18, heat is easily trapped inside the CFRP sleeve 20. Therefore, without any measures, it is difficult to suppress the temperature rise of the magnet 14 and the metal sleeve 18. In contrast, in the rotor 4 described above, a gap 24 is formed in the CFRP sleeve 20 such that the outer peripheral surface 18b of the metal sleeve 18 is partially exposed. Therefore, if... Figure 2As indicated by arrow f, cooling gas (e.g., air) flowing axially between the rotor 4 and the stator 10 can be supplied to the outer peripheral surface 18b of the metal sleeve 18 via the gap 24, thereby cooling the metal sleeve 18. Therefore, the scattering of the magnet 14 can be suppressed by the metal sleeve 18, and the increase in rotor 4 vibration caused by the thermal expansion of the metal sleeve 18 can be suppressed.

[0038] In several implementations, for example, Figure 1 As shown, if the thickness of the CFRP sleeve 20 is set to t0, and the size of each gap 24 in the axial direction is set to d, then d > t / 5 can also be satisfied. That is, d can also be greater than the value obtained by dividing t by 5.

[0039] If the size of the axial gap 24 is too small, it will be difficult to generate convective heat transfer of the cooling gas flowing axially. However, according to the rotor 4, by setting a gap 24 that satisfies d > t / 5, such as Figure 2 As shown, the flow of cooling gas along the outer circumferential surface of the CFRP sleeve 20 into the aforementioned gap 24 generates vortices, increasing the heat transfer rate of convective heat transfer. Therefore, the metal sleeve 18 can be effectively cooled using the cooling gas flowing along the axial direction.

[0040] Figure 3 This is a schematic cross-sectional view showing a portion of the electric motor 2 in another embodiment.

[0041] exist Figure 3 Unless otherwise specified, the various structures of the electric motor 2 shown are similar to those of the motor. Figure 1 The symbols for the same structure of the electric motor 2 shown are as follows: Figure 1 The motor 2 shown has the same structure for all components, so the description is omitted.

[0042] Figure 3 The motor 2 shown is a CFRP sleeve 20 including a first sleeve 20A and a second sleeve 20B.

[0043] The first sleeve 20A is made of carbon fiber reinforced plastic and is mounted on the outer peripheral surface 18b of the metal sleeve 18. The first sleeve 20A has a cylindrical shape and is arranged on a concentric circle relative to the shaft 12. The inner peripheral surface 20Aa of the first sleeve 20A is fixed to the outer peripheral surface 18b of the metal sleeve 18.

[0044] The second sleeve 20B is made of carbon fiber reinforced plastic and is axially spaced from the first sleeve 20A and mounted on the outer peripheral surface 18b of the metal sleeve 18. The second sleeve 20B has a cylindrical shape and is arranged concentrically relative to the shaft 12. The inner peripheral surface 20Ba of the second sleeve 20B is fixed to the outer peripheral surface 18b of the metal sleeve 18.

[0045] exist Figure 3In the illustrated embodiment, a gap 24 is formed between the first sleeve 20A and the second sleeve 20B, exposing a portion of the outer peripheral surface 18b of the metal sleeve 18. That is, the gap 24 is formed between the first sleeve 20A and the second sleeve 20B such that when viewed radially from the outer side, the outer peripheral surface 18b of the metal sleeve 18 can be seen through the gap 24. The gap 24 is formed circumferentially throughout the space between the first sleeve 20A and the second sleeve 20B. The gap 24 is formed axially within a region including the central position Pc of the metal sleeve 18. Figure 3 (The range indicated by arrow d in the text).

[0046] Figure 3 The rotor 4 shown can also be manufactured by mounting the first sleeve 20A and the second sleeve 20B onto the aforementioned assembly while the parts of the rotor 4 other than the first sleeve 20A and the second sleeve 20B (the assembly consisting of the shaft 12, magnet 14, end rings 15 and 16, and metal sleeve 18) are cooled to a temperature lower than that of the first sleeve 20A and the second sleeve 20B respectively. That is, Figure 3 The rotor 4 shown can also be manufactured by cold-fitting the axial ends of an assembly consisting of a shaft 12, a magnet 14, end rings 15 and 16, and a metal sleeve 18 into the first sleeve 20A and the second sleeve 20B, respectively. Additionally, Figure 3 The rotor 4 shown can also be manufactured by pressing the axial ends of the assembly consisting of shaft 12, magnet 14, end rings 15 and 16 and metal sleeve 18 into the first sleeve 20A and the second sleeve 20B, respectively.

[0047] according to Figure 3 The rotor 4 shown has a gap 24 formed between the first sleeve 20A and the second sleeve 20B. Therefore, it is not necessary to provide radially penetrating holes in the first sleeve 20A and the second sleeve 20B respectively for cooling the metal sleeve 18. Thus, it is possible to suppress the reduction in strength of the first sleeve 20A and the second sleeve 20B and to suppress the increase in processing costs.

[0048] In addition, according to Figure 3 The rotor 4 shown has a gap 24 provided in the area including the central position Pc of the axial metal sleeve 18, considering the problem that thermal expansion is prone to occur at the central position Pc of the axial metal sleeve 18. This effectively cools the area including the central position Pc within the metal sleeve 18, effectively suppressing the increase in vibration of the rotor 4 caused by the thermal expansion of the metal sleeve 18.

[0049] Figure 4 This is a schematic cross-sectional view showing a portion of the electric motor 2 in another embodiment. Figure 4 Unless otherwise specified, the various structures of the electric motor 2 shown are similar to those of the motor. Figure 3 The symbols for the same structure of the electric motor 2 shown are as follows: Figure 3 The motor 2 shown has the same structure for all components, so the description is omitted.

[0050] Figure 4 The rotor 4 shown is Figure 3 The rotor 4 shown differs in that an annular protrusion 19 protruding radially outward is formed on the outer peripheral surface 18b of the metal sleeve 18. The protrusion 19 is disposed between the first sleeve 20A and the second sleeve 20B.

[0051] exist Figure 4 In the structure shown, the end face 20Ab of the first sleeve 20A facing the second sleeve 20B contacts the side surface 19a of the protrusion 19 on the first sleeve 20A side, thereby axially positioning the first sleeve 20A. Similarly, the end face 20Bb of the second sleeve 20B facing the first sleeve 20A side contacts the side surface 19b of the protrusion 19 on the second sleeve 20B side, thereby axially positioning the second sleeve 20B. In other words, the protrusion 19 functions as a positioning part that determines the axial position of each of the first sleeve 20A and the second sleeve 20B. Therefore, the manufacturing management of the rotor 4 is simplified.

[0052] Furthermore, if we define the thickness of the metal sleeve 18 within the axially oriented range S1 containing the first sleeve 20A as t1, the thickness of the metal sleeve 18 within the axially oriented range S2 containing the second sleeve 20B as t2, and the thickness of the metal sleeve 18 within the axially oriented range S3 containing the gap 24 as t3, then t3 is greater than both t1 and t2. That is, t3 > t1 and t3 > t2 are satisfied.

[0053] Within the range S3 in which the axial gap 24 is provided, the fastening strength of the magnet 14 tends to decrease partially. Therefore, by making t3 larger than t1 and t2 respectively as described above, the decrease in the fastening strength of the magnet 14 within the range S3 in which the axial gap 24 is provided can be suppressed.

[0054] In several implementations, Figures 1-4 In the rotor 4 of each of the electric motors 2 shown, the magnet 14 may also be composed of multiple magnet components 21 divided along the axial direction (see reference). Figure 5 ) constitutes. In Figure 5 In the example shown, multiple magnet components 21 are arranged axially, and each magnet component 21 is formed into a ring. The multiple magnet components 21 are respectively arranged on concentric circles relative to the shaft 12, and the inner peripheral surface 21a of the magnet component 21 is fixed to the outer peripheral surface 12a of the shaft 12.

[0055] If magnet 14 is divided along the axial direction, the increase in the heat generated by magnet 14 can be suppressed. On the other hand, there is a tendency for the heat generated by metal sleeve 18 to increase, but... Figures 1-4 In each of the rotors 4 shown, the metal sleeve 18 can be effectively cooled through the gap 24, so that when the magnet 14 is divided along the axial direction, the temperature rise of the magnet 14 and the metal sleeve 18 can be effectively suppressed.

[0056] Figure 6 It means that it can be applied. Figures 1-4 A schematic diagram of an example of the general structure of the steam compressor 50 of the electric motor 2 shown.

[0057] Figure 6 The exemplary steam compressor 50 shown includes an electric motor 2 and multiple compressors driven by the electric motor 2 (two compressors 52 and 54 in the illustrated example). The impeller 52a of the compressor 52 is connected to one end of the shaft 12 of the rotor 4 in the electric motor 2, and the impeller 54a of the compressor 54 is connected to the other end of the shaft 12 of the rotor 4.

[0058] Compressor 52 compresses steam by rotating impeller 52a using the driving force of motor 2, and compressor 54 compresses steam by rotating impeller 54a using the driving force of motor 2.

[0059] exist Figure 6 In the vapor compressor shown, the vapor compressed by compressors 52 and 54 is a different type of gas from the motor cooling gas (air in the illustrated example) used to cool motor 2. In this case, when the pressure of the motor cooling gas is increased to allow a large amount of motor cooling gas to flow into motor 2, the motor cooling gas may leak into the main flow (vapor flow) on the compressor 52 and 54 sides. Therefore, there are limits to the pressure and flow rate of the motor cooling gas used for cooling motor 2.

[0060] Regarding this, by Figures 1-4 The electric motor 2 shown is used in the steam compressor 50. It can suppress the increase in pressure and flow rate of the cooling gas of the electric motor and can effectively cool the rotor 4 of the electric motor 2, so that the electric motor 2 can be used appropriately.

[0061] In addition, Figure 6In the vapor compressor 50 shown, the motor cooling gas for the rotor 4 of the cooling motor 2 and the cooling gas for the bearing assembly 8 are the same gas (air in the illustrated example). In such a configuration, when cooling gas is supplied to the rotor 4 and the bearing assembly 8 from a common cooling gas supply source, the proportion of the flow rate of cooling gas supplied to the rotor 4 is reduced compared to the amount of cooling gas supplied to the bearing assembly 8, thus creating a tendency to require cooling the rotor 4 with a small amount of cooling gas.

[0062] Regarding this, by Figures 1-4 The electric motor 2 shown is used in the steam compressor 50 and can effectively cool the rotor 4 of the electric motor 2 with a small amount of electric motor cooling gas, so the electric motor 2 can be used appropriately.

[0063] This disclosure is not limited to the above-described embodiments, but also includes modifications to the above-described embodiments and appropriate combinations of these embodiments.

[0064] For example, Figures 1-4 The electric motors 2 shown can be used to drive compressors in each stage of a multi-stage vapor compressor, or to drive compressors in a heat pump. In a heat pump, the heat medium compressed by the compressor and the cooling gas (e.g., air) used to cool the electric motor driving the compressor are different types of gases. Similar to the vapor compressor described above, there are limitations on the pressure and flow rate of the cooling gas used to cool the electric motor 2. Therefore, by… Figures 1-4 The electric motor 2 shown is used as an electric motor to drive the compressor of the heat pump. It can effectively cool the rotor 4 of the electric motor 2 with a small amount of electric motor cooling gas, and the electric motor 2 can be used appropriately.

[0065] in addition, Figures 1-4 The rotor 4 shown can also be used as a rotor for a generator, and can be used as a rotor for a rotating motor (electric motor or generator).

[0066] In addition, Figures 1-4 In each of the rotors 4 shown, a CFRP sleeve 20 is exemplified as a non-metallic sleeve mounted on the outer peripheral surface of the metal sleeve 18. However, the non-metallic sleeve mounted on the outer peripheral surface of the metal sleeve 18 may also be made of other resin-containing materials such as fiber-reinforced plastics other than CFRP.

[0067] in addition, Figures 1-4 Each rotor 4 shown includes a shaft 12 and a cylindrical magnet 14 mounted on the outer peripheral surface 12a of the shaft 12. However, it is not necessary to provide a shaft 12 inside the magnet 14. The rotor 4 may also include, for example, a solid cylindrical magnet 14, the aforementioned metal sleeve 18, and a CFRP sleeve 20.

[0068] In addition, Figure 1 The CFRP sleeve 20 shown has multiple gaps 24 formed in such a way that the outer peripheral surface 18b of the metal sleeve 18 is partially exposed. However, the number of gaps 24 formed in the CFRP sleeve 20 in such a way that the outer peripheral surface 18b of the metal sleeve 18 is partially exposed can also be one.

[0069] The contents described in the above embodiments are as follows.

[0070] [1] A rotor for a rotary electric motor (e.g., rotor 4 as described above) according to at least one embodiment of the present disclosure includes: a magnet (e.g., magnet 14 as described above); a metal sleeve (e.g., metal sleeve 18 as described above), which is made of a metal material and is provided to cover the magnet; and at least one non-metallic sleeve (e.g., CFRP sleeve 20, first sleeve 20A, second sleeve 20B as described above), which is made of a non-metallic material and is mounted on the outer peripheral surface (e.g., outer peripheral surface 18b as described above), and a gap (e.g., gap 24 as described above) is formed in the at least one non-metallic sleeve in such a way that the outer peripheral surface of the metal sleeve is partially exposed.

[0071] According to the rotor for a rotary electric machine described above [1], the scattering of magnets in the event of magnet breakage can be suppressed by using a metal sleeve covering the magnets. Furthermore, by installing at least one non-metallic sleeve on the outer circumferential surface of the metal sleeve, the thermal expansion of the metal sleeve can be suppressed using the non-metallic sleeve. Here, if a non-metallic sleeve is installed on the outer circumferential surface of the metal sleeve, heat tends to remain inside the non-metallic sleeve, making it difficult to suppress the temperature rise of the magnets and the metal sleeve without taking any measures. However, in the rotor for a rotary electric machine described above [1], a gap is formed on at least one non-metallic sleeve such that the outer circumferential surface of the metal sleeve is partially exposed. Therefore, cooling gas can be supplied to the outer circumferential surface of the metal sleeve through the gap to cool the metal sleeve. Thus, the scattering of magnets can be suppressed by the metal sleeve, and the increase in rotor vibration caused by the thermal expansion of the metal sleeve can be suppressed.

[0072] [2] In several embodiments, in the rotor for the rotary motor described in [1] above, the thickness of the non-metallic sleeve is set to t0, and the size of the gap in the axial direction of the rotor is set to d, then d > t0 / 5.

[0073] If the size of the aforementioned axial gap is too small, it is difficult to generate convective heat transfer of the cooling gas flowing along the axial direction. However, according to the rotor for the rotary motor described above [2], by setting a gap that satisfies d > t / 5, the cooling gas flowing along the outer circumference of the non-metallic sleeve flows into the aforementioned gap and generates eddies, thereby increasing the heat transfer rate of convective heat transfer. Therefore, the metal sleeve can be effectively cooled by utilizing the cooling gas flowing along the axial direction.

[0074] [3] In several embodiments, in the rotor for the rotary motor described in [1] or [2] above, the at least one non-metallic sleeve includes: a non-metallic first sleeve (e.g., the first sleeve 20A described above), which is mounted on the outer peripheral surface of the metal sleeve; and a non-metallic second sleeve (e.g., the second sleeve 20B described above), which is arranged axially spaced relative to the non-metallic first sleeve in the rotor and mounted on the outer peripheral surface of the metal sleeve, the gap being formed between the non-metallic first sleeve and the non-metallic second sleeve.

[0075] According to the rotor for the rotary motor described above [3], compared with the case where a through hole is provided in the non-metallic sleeve as the aforementioned gap, it is not necessary to provide through holes in the non-metallic first sleeve and the non-metallic second sleeve respectively. Therefore, it is possible to suppress the reduction in strength of the non-metallic first sleeve and the non-metallic second sleeve, and to reduce processing costs.

[0076] [4] In several embodiments, in the rotor for a rotary electric machine described in [3] above, the gap is formed throughout the circumferential direction of the rotor between the non-metallic first sleeve and the non-metallic second sleeve.

[0077] The rotor for the rotary motor described above [4] can effectively cool the metal sleeve.

[0078] [5] In several embodiments, in the rotor for the rotary electric machine described in [3] or [4] above, the gap is formed in the axial direction within a range (e.g., the range corresponding to the arrow d above) of the central position (e.g., the position Pc described above) including the metal sleeve.

[0079] According to the rotor for the rotary electric motor described above [5], since thermal expansion is prone to occur at the central position of the metal sleeve in the axial direction, the aforementioned gap is provided in the range including the central position of the metal sleeve in the axial direction. As a result, the range including the central position of the metal sleeve in the axial direction can be effectively cooled, and the increase in rotor vibration caused by the thermal expansion of the metal sleeve can be effectively suppressed.

[0080] [6] In several embodiments, in the rotor for a rotary electric motor described in any one of [3] to [5] above, a protrusion (e.g., the protrusion 19 described above) is formed on the outer peripheral surface of the metal sleeve, protruding outward in the radial direction toward the rotor, the protrusion being located between the non-metallic first sleeve and the non-metallic second sleeve.

[0081] According to the rotor for a rotary motor described above [6], by making the non-metallic first sleeve and the non-metallic second sleeve contact the two end faces of the axial protrusion, the non-metallic first sleeve and the non-metallic second sleeve can be positioned in the axial direction, making the manufacturing management of the rotor for a rotary motor easier.

[0082] [7] In several embodiments, in the rotor for a rotary electric machine described above [6], the protrusion is formed throughout the circumferential direction of the rotor.

[0083] According to the rotor for a rotary motor described above [7], by making the non-metallic first sleeve and the non-metallic second sleeve contact the two end faces of the axial protrusion, the non-metallic first sleeve and the non-metallic second sleeve can be positioned in the axial direction, making the manufacturing management of the rotor for a rotary motor easier.

[0084] [8] In several embodiments, in the rotor for the rotary motor described in [6] or [7] above, the end face of the non-metallic first sleeve (e.g., the end face 20Ab described above) contacts one side of the axially protruding portion (e.g., side 19a described above), and the end face of the non-metallic second sleeve (e.g., the end face 20Bb described above) contacts the other side of the axially protruding portion (e.g., side 19b described above).

[0085] According to the rotor for rotary motor described above [8], the non-metallic first sleeve and the non-metallic second sleeve can be positioned in the axial direction, making the manufacturing management of the rotor for rotary motor easier.

[0086] [9] In several embodiments, in the rotor for the rotary electric motor described in any one of [3] to [8] above, the thickness of the metal sleeve in the axial region where the non-metallic first sleeve is provided (e.g., the range S1 described above) is set as t1, the thickness of the metal sleeve in the axial region where the non-metallic second sleeve is provided (e.g., the range S2 described above) is set as t2, and the thickness of the metal sleeve in the axial region where the gap is provided (e.g., the range S3 described above) is set as t3, then t3 is greater than t1 and t2 respectively.

[0087] In the range where there is a gap in the axial direction, the fastening strength of the magnet tends to decrease. Therefore, by making t3 larger than t1 and t2 respectively as described above [9], the decrease in the fastening strength of the magnet in the range where there is a gap in the axial direction can be suppressed.

[0088]

[10] In several embodiments, in the rotor for the rotary electric machine described in [1] or [2] above, a through hole (e.g., with) is formed in the non-metallic sleeve that extends radially through the rotor. Figure 1 (the through hole corresponding to the gap 24), the gap being the through hole.

[0089] The rotor for a rotary electric motor described in

[10] above reduces the number of components compared to the rotor for a rotary electric motor described in [3] above.

[0090]

[11] In several embodiments, in the rotor of the rotary electric machine described in any one of [1] to

[10] above, the metal sleeve is cold-fitted into the non-metallic sleeve.

[0091] According to the rotor for the rotary motor described above

[11] , the non-metallic sleeve can be easily fixed to the metal sleeve.

[0092]

[12] In several embodiments, in the rotor of the rotary electric machine described in any one of [1] to

[11] above, the non-metallic sleeve is made of a resin-containing material.

[0093] According to the rotor for the rotary motor described above

[12] , since eddy currents are not generated in the non-metallic sleeve, the thermal expansion of the metal sleeve can be suppressed by the non-metallic sleeve, and the thermal expansion of the non-metallic sleeve can also be suppressed.

[0094]

[13] In several embodiments, in the rotor for the rotary electric machine described in

[12] above, the non-metallic sleeve is made of carbon fiber reinforced plastic.

[0095] According to the rotor for the rotary motor described above

[13] , since eddy currents are not generated in the non-metallic sleeve, the thermal expansion of the metal sleeve can be suppressed by using a lightweight and high-strength non-metallic sleeve, and the thermal expansion of the non-metallic sleeve can also be suppressed.

[0096]

[14] The rotary electric motor of at least one embodiment of the present disclosure includes a rotor and a stator (e.g., the stator 10 described above) for a rotary electric motor as described in any one of [1] to

[13] .

[0097] According to the rotary motor described above

[14] , since it has a rotor for a rotary motor as described in any one of [1] to

[13] above, it is possible to suppress the scattering of magnets by means of a metal sleeve, and to suppress the increase in rotor vibration caused by the thermal expansion of the metal sleeve.

[0098] Explanation of reference numerals in the attached figures

[0099] 2: Electric motor

[0100] 4: Rotor

[0101] 8: Bearing assembly

[0102] 10: Stator

[0103] 12: Axis

[0104] 12a, 14b, 15b, 16b, 18b: outer peripheral surface

[0105] 14: Magnet

[0106] 14a, 15a, 16a, 18a, 20Aa, 20Ba, 20a, 21a: Inner circumferential surface

[0107] 15, 16: End rings

[0108] 18: Metal sleeve

[0109] 19: Protrusion

[0110] 19a, 19b: Side view

[0111] 20: CFRP sleeve

[0112] 20A: First Sleeve

[0113] 20Ab, 20Bb: End face

[0114] 20B: Second sleeve

[0115] 21: Magnet component

[0116] 24: Gap

[0117] 50: Steam compressor

[0118] 52, 54: Compressor

[0119] 52a, 54a: Impeller

Claims

1. A rotor for a rotary electric motor, characterized in that, have: magnet; A metal sleeve, made of metal, is provided to cover the magnet; At least one non-metallic sleeve, made of non-metallic material, is installed on the outer circumferential surface of the metallic sleeve; A gap is formed in the at least one non-metallic sleeve in such a way that the outer peripheral surface of the metallic sleeve is exposed.

2. The rotor for a rotary electric motor according to claim 1, characterized in that, Let the thickness of the non-metallic sleeve be t0, and the size of the axial gap of the rotor be d, then d > t0 / 5.

3. The rotor for a rotary electric motor according to claim 1, characterized in that, The at least one non-metallic sleeve includes: a first non-metallic sleeve mounted on the outer peripheral surface of the metal sleeve; and a second non-metallic sleeve, spaced apart from the first non-metallic sleeve in the axial direction of the rotor, mounted on the outer peripheral surface of the metal sleeve. The gap is formed between the non-metallic first sleeve and the non-metallic second sleeve.

4. The rotor for a rotary electric motor according to claim 3, characterized in that, The gap is formed integrally across the circumference of the rotor between the non-metallic first sleeve and the non-metallic second sleeve.

5. The rotor for a rotary electric machine according to claim 4, characterized in that, The gap is formed in the range that includes the central position of the metal sleeve in the axial direction.

6. The rotor for a rotary electric motor according to claim 3, characterized in that, A protrusion is formed on the outer peripheral surface of the metal sleeve, projecting radially outward toward the rotor. The protrusion is located between the non-metallic first sleeve and the non-metallic second sleeve.

7. The rotor for a rotary electric machine according to claim 6, characterized in that, The protrusion is formed throughout the entire circumference of the rotor.

8. The rotor for a rotary electric motor according to claim 6, characterized in that, The end face of the non-metallic first sleeve contacts the side surface of the protrusion on one side in the axial direction. The end face of the non-metallic second sleeve contacts the side face of the protrusion on the other side in the axial direction.

9. The rotor for a rotary electric motor according to claim 3, characterized in that, Let t1 be the thickness of the metal sleeve within the range of the non-metallic first sleeve in the axial direction, let t2 be the thickness of the metal sleeve within the range of the non-metallic second sleeve in the axial direction, and let t3 be the thickness of the metal sleeve within the range of the gap in the axial direction. Then t3 is greater than t1 and t2, respectively.

10. The rotor for a rotary electric machine according to claim 1, characterized in that, A through hole is formed in the non-metallic sleeve, extending radially along the rotor. The gap is the through hole.

11. The rotor for a rotary electric machine according to claim 1, characterized in that, The metal sleeve is cold-fitted into the non-metallic sleeve.

12. The rotor for a rotary electric machine according to claim 1, characterized in that, The non-metallic sleeve is made of a resin-containing material.

13. The rotor for a rotary electric machine according to claim 12, characterized in that, The non-metallic sleeve is made of carbon fiber reinforced plastic.

14. A rotary electric motor, characterized in that, The rotating electric motor comprises a rotor and a stator as described in any one of claims 1 to 13.

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