Rotating electrical machine case, rotating electrical machine, and method for manufacturing a rotating electrical machine case

Abstract

The present invention provides a rotating electric machine case, a rotating electric machine, and a method for manufacturing a rotating electric machine case, which allow for relatively free modification of the refrigerant path to suit the electrical configuration of the rotating electric machine and external heat sources. [Solution] The rotating electric machine case comprises a cylindrical frame capable of housing a stator and a rotor inside, and brackets provided on both ends of the frame and covering the openings on both sides of the frame. The frame has a plurality of frame-side refrigerant paths that are configured to allow refrigerant to flow through and are formed to penetrate the frame from one end to the other. The brackets have bracket-side refrigerant paths that are configured to allow refrigerant to flow through and are connected to the ends of the frame-side refrigerant paths, connecting each frame-side refrigerant path.

Description

Technical Field

[0001] Embodiments of the present invention relate to a rotating electrical machine case, a rotating electrical machine, and a method for manufacturing a rotating electrical machine case.

Background Art

[0002] For example, a rotating electrical machine such as an in-vehicle motor may be cooled by providing a refrigerant path for flowing a refrigerant in a case that houses a stator and a rotor and flowing the refrigerant through the refrigerant path. Usually, the flow path of such a case is dedicatedly designed according to the electrical configuration of the rotating electrical machine and external heat sources such as an engine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the case of a conventional configuration, for example, even if the shape of the case is the same, it is necessary to change the arrangement of the refrigerant path according to the electrical configuration of the rotating electrical machine and external heat sources, and the design change is time-consuming.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotating electrical machine case, a rotating electrical machine, and a method for manufacturing a rotating electrical machine case that can relatively freely change the refrigerant path according to the electrical configuration of the rotating electrical machine and external heat sources.

Means for Solving the Problems

[0006] The rotating electric machine case according to this embodiment comprises a cylindrical frame capable of housing a stator and a rotor inside, and brackets provided on both ends of the frame and covering the openings on both sides of the frame. The frame has a plurality of frame-side refrigerant paths that are configured to allow refrigerant to flow through the frame and are formed to penetrate the frame from one end to the other. The brackets have bracket-side refrigerant paths that are configured to allow refrigerant to flow through them and are connected to the ends of the frame-side refrigerant paths, connecting each of the frame-side refrigerant paths.

[0007] The rotating electric machine according to this embodiment comprises a stator and a rotor, and a rotating electric machine case housing the stator and the rotor. The rotating electric machine case has a cylindrical frame capable of housing the stator and the rotor inside, and brackets provided on both ends of the frame and covering the openings on both sides of the frame. The frame has a plurality of frame-side refrigerant paths that are configured to allow refrigerant to flow through the frame and are formed to penetrate the frame from one end to the other. The brackets have bracket-side refrigerant paths that are configured to allow refrigerant to flow through them and are connected to the ends of the frame-side refrigerant paths, connecting each of the frame-side refrigerant paths.

[0008] The method for manufacturing a rotating electric machine case according to this embodiment includes a step of manufacturing the frame by extrusion molding. [Brief explanation of the drawing]

[0009] [Figure 1] A partial cross-sectional view showing the schematic configuration of an example of a rotating electric machine according to one embodiment. [Figure 2] Figure 1 shows an example of a rotating electric machine according to one embodiment, viewed from the X2 direction. [Figure 3] A cross-sectional view of an example of a rotating electric machine according to one embodiment, shown along the line X3-X3 in Figure 1. [Figure 4] A cross-sectional view of an example of a rotating electric machine according to one embodiment, shown along the line X4-X4 in Figure 1. [Figure 5]A cross-sectional view of an example of a rotating electric machine according to one embodiment, shown along the line X5-X5 in Figure 1. [Figure 6] A cross-sectional view showing a rotating electric machine according to one embodiment, unfolded along line X6 in Figure 2, as an example. [Figure 7] Figure 4 shows an example of a rotating electric machine according to one embodiment, with a bracket from another example attached. [Figure 8] Figure 6 shows an example of a rotating electric machine according to one embodiment, with a bracket from another example attached. [Figure 9] A schematic diagram showing a method for manufacturing a rotating electric machine according to one embodiment. [Modes for carrying out the invention]

[0010] The following describes a rotating electric machine case, a rotating electric machine, and a method for manufacturing the rotating electric machine case according to one embodiment, with reference to the drawings. The rotating electric machine of this embodiment can be applied to, for example, an electric motor for use in a vehicle, but its application is not limited to this. The rotating electric machine 10 shown in Figure 1 comprises a stator 11, a rotor 12, a rotating shaft 13, a bearing 14, and a rotating electric machine case 20. In the following description, the direction parallel to the center O of the rotating shaft 13 is referred to as the axial direction. The direction perpendicular to the center O is referred to as the radial direction. In the following description, the rotating electric machine case 20 may be simply referred to as the case 20.

[0011] The stator 11, rotor 12, and part of the rotating shaft 13 are housed within the case 20. The stator 11 is fixed to the inside of the case 20. The stator 11 includes, for example, a stator core 111 and stator windings 112. The stator core 111 is, for example, cylindrical and formed by laminating multiple disc-shaped electromagnetic steel sheets. The stator windings 112 are wound around the stator core 111.

[0012] The rotor 12 is rotatably mounted inside the stator 11 with a gap between it and the stator 11. That is, the rotating electric machine 10 of this embodiment can be configured as, for example, an inner rotor type rotating electric machine. The rotor 12 can be configured with a squirrel-cage conductor, a rotor core and windings, or a rotor core and permanent magnets.

[0013] The rotating shaft 13 is provided through the center of the rotor 12 and is configured to rotate integrally with the rotor 12. Both ends of the rotating shaft 13 are rotatably supported by the case 20 via bearings 14. The bearings 14 can be made of, for example, ball bearings.

[0014] The case 20 constitutes the outer shell of the rotating electric machine 10 and houses the stator 11 and rotor 12 inside. The case 20 comprises a frame 30 and brackets 40. In this embodiment, the case 20 comprises one frame 30 and two brackets 40. The centers of the frame 30 and brackets 40 coincide with the center O of the rotation axis 13.

[0015] The frame 30 is formed in a cylindrical shape with a circular or polygonal outer shape and an internal space having a circular cross-section perpendicular to the axial direction of the rotation axis 13, with openings 301 formed at both ends. The frame 30 is configured to accommodate the stator 11 and rotor 12 inside the cylindrical structure. The frame 30 is made of a rigid material such as steel, aluminum, or reinforced resin. The frame 30 is configured such that the cross-section obtained by cutting along the radial direction of the rotation axis 13 is the same regardless of the position in the axial direction of the rotation axis 13 at which it is cut.

[0016] The bracket 40 has a circular or polygonal outer shape and is formed in a plate shape as a whole. The bracket 40 is made of a rigid material such as steel, aluminum, or reinforced resin. The bracket 40 is provided with the bearing 14 attached thereto and is provided on both end sides of the frame 30 to close the opening 301 of the frame 30. In this case, for the bracket 40 to close the opening 301, it is only necessary that the bracket 40 covers most of the opening 301, and it is not necessary to close the opening 301 in a watertight or airtight manner. The bracket 40 is provided on both sides of the case 20, for example. The rotating shaft 13 passes through one or both of the two brackets 40 and is rotatably supported by the bracket 40 via the bearing 14.

[0017] As shown in FIGS. 1, 3, and 6, the frame 30 has a plurality of frame-side refrigerant passages 31. The frame-side refrigerant passages 31 are configured to allow a liquid refrigerant such as water or a gaseous refrigerant to flow therethrough. The frame-side refrigerant passages 31 are formed so as to penetrate the frame 30 from one end side to the other end side of the frame 30. That is, the frame-side refrigerant passages 31 are formed by penetrating the wall portion forming the periphery of the frame 30, that is, the portion surrounding the stator 11 in the frame 30, in the axial direction of the rotor 12.

[0018] As shown in FIG. 3, each of the frame-side refrigerant passages 31 is arranged at equal intervals at a predetermined angle θ degrees on a concentric circle centered on the center O of the frame 30, for example. In the description of the present embodiment, "the frame-side refrigerant passages 31 are arranged at an interval of θ degrees" means that the angle between the circumferential centers of the frame-side refrigerant passages 31 is θ degrees. In this case, if the number of the frame-side refrigerant passages 31 is X, the predetermined angle θ can be 360 / X (degrees). In the case of the present embodiment, the frame 30 has 24 frame-side refrigerant passages 31. Therefore, the arrangement angle θ of adjacent frame-side refrigerant passages 31 is 15 degrees. That is, each of the frame-side refrigerant passages 31 is arranged at an interval of 15 degrees on a concentric circle centered on the center O of the frame 30.

[0019] In addition, each frame-side refrigerant path 31 may be arranged at a predetermined interval that is not equally spaced on a concentric circle centered on the center O of the frame 30, for example. Also, each frame-side refrigerant path 31 is configured in a straight line parallel to the axial direction of the rotor 12. Note that each frame-side refrigerant path 31 may be configured in a so-called spiral shape having an angle with respect to the axial direction of the rotor 12.

[0020] As shown in FIGS. 1, 4, and 6, the bracket 40 has a plurality of bracket-side refrigerant paths 41. Similar to the frame-side refrigerant path 31, the bracket-side refrigerant path 41 is configured to allow a liquid refrigerant such as water or a gaseous refrigerant to flow therethrough. As shown in FIGS. 1 and 6, the bracket-side refrigerant path 41 has a function of connecting to the end of the frame-side refrigerant path 31 and connecting each frame-side refrigerant path 31 by attaching the bracket 40 to the end of the frame 30.

[0021] The bracket-side refrigerant path 41 has a non-penetrating structure as shown in FIG. 6, for example, and is formed by digging down the surface of the bracket 40 on the frame 30 side in the axial direction of the rotation axis 13. As shown in FIG. 4, each bracket-side refrigerant path 41 is arranged at equal intervals at a predetermined angle of 2θ degrees on a concentric circle centered on the center O of the bracket 40 and on the circumference where the frame-side refrigerant path 31 is arranged. That is, the angle of 2θ degrees of the frame-side refrigerant path 31 is twice the angle θ at which the frame-side refrigerant path 31 is arranged. In the description of the present embodiment, "the bracket-side refrigerant paths 41 are arranged at intervals of 2θ degrees" means that the angle between the centers in the circumferential direction of the bracket-side refrigerant paths 41 is 2θ degrees.

[0022] The frame-side refrigerant path 31 and the bracket-side refrigerant path 41 constitute the path through which the refrigerant flows. For example, as shown in Figures 4 to 6, the bracket-side refrigerant path 41 connects the ends of two adjacent frame-side refrigerant paths 31 when the bracket 40 is attached to the frame 30. That is, in the example shown in Figures 4 to 6, each bracket 40 has 12 bracket-side refrigerant paths 41. Therefore, the arrangement angle 2θ of adjacent bracket-side refrigerant paths 41 is 30 degrees. In other words, each bracket-side refrigerant path 41 is arranged at 30-degree intervals on a concentric circle centered on the center O of the frame 30 and on the circumference where the frame-side refrigerant paths 31 are arranged.

[0023] As shown in Figures 1, 2, and 6, one or both of the two brackets 40 provided at both ends of the frame 30 have an inlet portion 42 and an outlet portion 43. In this embodiment, the inlet portion 42 and the outlet portion 43 are provided on the bracket 40 that is not penetrated by the rotating shaft 13. The inlet portion 42 and the outlet portion 43 are provided through the bracket 40 and communicate with the bracket-side refrigerant path 41. Piping connected to a refrigerant heat dissipation and circulation device (not shown), such as a radiator or pump, is connected to the inlet portion 42 and the outlet portion 43.

[0024] The two brackets 40 provided at both ends of the frame 30 share the same shape and arrangement of the bracket-side refrigerant path 41. In this case, the two brackets 40 are formed in the same shape except for the inlet portion 42 and outlet portion 43 on one of them. The two brackets 40 are attached to the frame 30 in a position where they are rotated relative to each other by an angle that is an integer multiple of a predetermined angle θ around the center O, as shown in Figures 4 and 5. Therefore, as shown in Figure 6, both ends of each frame-side refrigerant path 31 are connected alternately by the bracket-side refrigerant path 41 of the two brackets 40. As a result, the inlet portion 42 and the outlet portion 43 are interconnected by the respective frame-side refrigerant path 31 and the respective bracket-side refrigerant path 41.

[0025] In this configuration, the refrigerant supplied from an external refrigerant heat dissipation and circulation device (not shown) flows from the inlet 42 into the bracket-side refrigerant path 41 and the frame-side refrigerant path 31, as shown in Figure 6. After flowing through the bracket-side refrigerant path 41 and the frame-side refrigerant path 31, it flows out again from the outlet 43 to the heat dissipation and circulation device. As a result, the case 20 can cool the stator 11 and rotor 12, etc., inside the case 20 with the refrigerant flowing through the bracket-side refrigerant path 41 and the frame-side refrigerant path 31.

[0026] In this embodiment, the inlet 42 and outlet 43 are located opposite each other on the bracket 40, with the center O in between, as shown in Figure 2. Therefore, the refrigerant flowing from the inlet 42 into the bracket-side refrigerant path 41 and the frame-side refrigerant path 31 branches into two paths, as shown by the white and black arrows in Figure 6, and then merges at the outlet 43 before flowing out. In this case, the paths shown by the white and black arrows are set to the same distance. Therefore, the inside of the case 20 can be cooled as uniformly as possible. Note that by changing the positional relationship, or arrangement angle, between the inlet 42 and the outlet 43, a difference in distance between the paths shown by the white and black arrows may be created.

[0027] Furthermore, the frame 30 can also be configured to have one or more spaces 32, as shown in Figures 1 and 3. In this embodiment, the frame 30 has multiple spaces 32. The spaces 32 are formed in a hollow shape that penetrates the frame 30 in the axial direction of the rotor 12. The spaces 32 are located radially outside the frame-side coolant path 31 and are arranged at equal intervals on concentric circles centered on the center O. In this embodiment, as shown in Figure 1, when the bracket 40 is attached to the frame 30, both ends of the spaces 32 are closed by the bracket 40. The spaces 32 are filled with air, which has a lower thermal conductivity than the frame 30. Therefore, it is possible to suppress the release of heat from inside the case 20 to the outside, and to suppress the heating of the inside of the case 20 by heat from outside the case 20.

[0028] Case 20 can also be configured to include, for example, the bracket 40A shown in Figures 7 and 8. In this case, the bracket 40A has the same configuration as the bracket 40 described above, except for the number and shape of the bracket-side refrigerant paths 41A. The bracket 40A is equipped with bracket-side refrigerant paths 41A. When the bracket 40A is attached to the frame 30, the bracket-side refrigerant paths 41A connect the ends of four adjacent frame-side refrigerant paths 31. That is, each bracket 40A has six bracket-side refrigerant paths 41A. The bracket-side refrigerant paths 41A are arranged at 60-degree intervals on a concentric circle centered on the center O of the frame 30 and on the circumference where the frame-side refrigerant paths 31 are located.

[0029] In this case, the two brackets 40A provided at both ends of the frame 30 are attached to the frame 30 in a position where they are rotated relative to each other by an angle that is an integer multiple of 30 degrees around the center O. As a result, as shown in Figure 8, both ends of each frame-side refrigerant path 31 are connected alternately by the bracket-side refrigerant paths 41A of the two brackets 40A. This makes it possible to increase the amount of refrigerant flowing per unit time through the frame-side refrigerant path 31 without changing the structure of the frame-side refrigerant path 31, thereby improving the cooling performance of the frame 30.

[0030] Furthermore, in this embodiment, the frame 30 is an extruded product rather than a typical cast product. That is, the manufacturing method for the case 20 includes a step of manufacturing the frame 30 used in the case 20 by extrusion molding. The manufacturing method for the case 20 uses, for example, the manufacturing apparatus 50 shown in Figure 9 to manufacture the frame 30. The manufacturing apparatus 50 includes, for example, a container 51, a press 52, and a die 53. The die 53 is provided at the tip of the container 51. The die 53 is composed of a male die 531 and a female die 532 for manufacturing hollow extruded products.

[0031] The manufacturing apparatus 50 uses, for example, a cylindrical block of aluminum or iron as the material 60. The manufacturing apparatus 50 manufactures the frame 30 as follows: The material 60 for the frame 30 is heated to near its recrystallization temperature and softened, and then set in the container 51. The manufacturing apparatus 50 then presses the softened material 60 against a die 53 using a press machine 52 to form it. After that, the extruded product is cooled in a cooling device (not shown) and cut to a predetermined length L, thereby manufacturing the frame 30.

[0032] According to the embodiment described above, the rotating electric machine 10 comprises a stator 11 and a rotor 12, and a rotating electric machine case 20. The rotating electric machine case 20 comprises a frame 30 and a bracket 40 or bracket 40A. The frame 30 is formed in a cylindrical shape and is configured to house the stator 11 and rotor 12 inside. The brackets 40 and 40A are provided on both ends of the frame 30 and cover the openings on both sides of the frame 30.

[0033] The frame 30 has a plurality of frame-side refrigerant paths 31. The frame-side refrigerant paths 31 are configured to allow refrigerant to flow and are formed to penetrate the frame 30 from one end to the other. The brackets 40 and 40A have bracket-side refrigerant paths 41 and 41A. The bracket-side refrigerant paths 41 and 41A are configured to allow refrigerant to flow and are connected to the ends of the frame-side refrigerant paths 31, connecting each frame-side refrigerant path 31.

[0034] In this case, the rotating electric machine 10 may have a heat source such as an engine placed near it, for example, in an automotive application. In this case, the rotating electric machine 10 is susceptible to radiant heat from the heat source such as the engine, and is at risk of overheating. In contrast, according to this embodiment, the shape and arrangement of the bracket-side refrigerant paths 41 and 41A can be changed to flexibly alter the path through which the refrigerant flows by changing the connection between the frame-side refrigerant path 31 and the bracket-side refrigerant paths 41 and 41A. For example, by changing the bracket-side refrigerant paths 41 and 41A of the brackets 40 and 40A, or by changing the mounting angle, the refrigerant path can be changed relatively freely to suit the electrical configuration of the rotating electric machine 10 and the external heat source, such as uniformly cooling the entire rotating electric machine 10 or focusing on cooling the part of the rotating electric machine 10 that is closer to the heat source.

[0035] Furthermore, the frame 30 has a space 32 that penetrates the frame 30 in the axial direction of the rotor 12. This space 32 suppresses the release of heat from inside the case 20 to the outside, and also suppresses the heating of the inside of the case 20 by heat from outside the case 20. This improves the thermal insulation of the frame 30 and more effectively reduces the influence of external heat sources. In addition, forming the space 32 contributes to reducing the weight of the frame 30.

[0036] Furthermore, the manufacturing method for the case 20 includes a step of manufacturing the frame 30 by extrusion molding. According to this, by making the frame 30 an extruded product, the length dimension of the case 20 can be easily changed without changing the brackets 40 and 40A, simply by adjusting the length dimension L to which the frame 30 is cut during manufacturing. In other words, by making the frame 30 an extruded product, the brackets 40 and 40A can be standardized even for rotating electric machines with different length dimensions for the stator 11 and rotor 12.

[0037] This means that, for example in manufacturing, by simply adjusting the dimensions of the frame 30, the same bracket 40, 40A can be used for rotating electric machines with stators 11 and rotors 12 of different lengths, thus reducing the number of types of parts used in the manufacturing process. This simplifies parts inventory management, reduces changes and switchovers to the production line, and improves production efficiency. Furthermore, since it can accommodate stators 11 and rotors 12 of different lengths simply by adjusting the dimensions of the frame 30, complex adjustments and design changes are unnecessary. This simplifies the design and manufacturing processes.

[0038] Furthermore, in sites where the rotating electric machine 10 is used, even if the stator 11 and rotor 12 have different length dimensions, the same brackets 40 and 40A are used, thus reducing the number of types of parts required for maintenance. This simplifies parts inventory management, contributes to simplifying maintenance work and shortening working time, and as a result, improves maintainability.

[0039] This disclosure is described in accordance with the embodiments, but it is understood that this disclosure is not limited to such embodiments or structures. This disclosure also includes various modifications and variations within the equivalence. In addition, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer of those elements, fall within the scope and concept of this disclosure. [Explanation of symbols]

[0040] 10...Rotating electric machine, 11...Stator, 12...Rotor, 20...Rotating electric machine case, 30...Frame, 31...Refrigerant path on the frame side, 32...Space, 40, 40A...Bracket, 41, 41A...Refrigerant path on the bracket side

Claims

1. A frame formed in a cylindrical shape and capable of housing a stator and rotor inside, Brackets are provided on both ends of the frame and cover the openings on both sides of the frame, Equipped with, The frame is configured to allow refrigerant to flow through it and has a plurality of frame-side refrigerant paths formed to penetrate the frame from one end to the other end. The bracket is configured to allow refrigerant to flow through it and has a bracket-side refrigerant path that is connected to the end of the frame-side refrigerant path and connects each of the frame-side refrigerant paths. Rotating electrical machine case.

2. The frame further has a space that penetrates the frame in the axial direction of the rotor. The rotating electric machine case according to claim 1.

3. Stator and rotor, The system comprises a stator and a rotating electric machine case housing the rotor, The aforementioned rotating electric machine case is A frame formed in a cylindrical shape and capable of housing the stator and rotor inside, Brackets are provided on both ends of the frame and cover the openings on both sides of the frame, It has, The frame is configured to allow refrigerant to flow through it and has a plurality of frame-side refrigerant paths formed to penetrate the frame from one end to the other end. The bracket is configured to allow refrigerant to flow through it and has a bracket-side refrigerant path that is connected to the end of the frame-side refrigerant path and connects each of the frame-side refrigerant paths. Rotating electric machine.

4. A frame formed in a cylindrical shape and capable of housing a stator and rotor inside, Brackets are provided on both ends of the frame and cover the openings on both sides of the frame, Equipped with, The frame is configured to allow refrigerant to flow through it and has a plurality of frame-side refrigerant paths formed to penetrate the frame from one end to the other end. The bracket is configured to allow refrigerant to flow through it and has a bracket-side refrigerant path that is connected to the end of the frame-side refrigerant path and connects each of the frame-side refrigerant paths. A method for manufacturing a rotating electric machine case, The process includes manufacturing the frame by extrusion molding. A method for manufacturing a rotating electrical machine case.

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