Stator coil

Abstract

To provide a stator coil that can efficiently ensure stable quality.SOLUTION: A stator coil is formed by connecting, by welding, wide surface at the ends of a plurality of base materials constituted of flat wires. An end of one base material is arranged orthogonal to an end of the other base material and is formed capable of being positioned relative to the end of the other base material.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a stator coil. [Background technology]

[0002] Conventionally, when a stator is created by inserting unit coils, each made of concentratedly wound rectangular wire, into the teeth of a stator core of a rotating electrical machine, connections are made between the unit coils and between the neutral point and the coils. These connections are sometimes made by welding the tips of the base materials to be connected together, using techniques such as TIG welding or laser welding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-213423 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when welding the tips of the base materials together, dedicated jigs are used to prevent misalignment between the base materials. However, this not only requires a lot of work, but also results in variations in quality because the positioning accuracy depends on the skill of the worker. This makes it difficult to efficiently obtain stable quality stator coils.

[0005] Therefore, an object of the present invention is to provide a stator coil that can efficiently ensure stable quality. [Means for solving the problem]

[0006] In order to solve the above problem, the stator coil is formed by welding together the wide surfaces at the ends of multiple base materials made of flat wire, and the end of one of the base materials is arranged perpendicular to the end of the other base material and is formed so that it can be positioned relative to the end of the other base material. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view schematically illustrating an example of a stator including a stator coil according to a first embodiment; [Figure 2] 1A is a perspective view showing an example of a configuration around the tips of a first end and a second end of a stator coil according to a first embodiment; FIG. 1B is a perspective view showing a state in which the first end and the second end are connected; [Figure 3] 1A is a perspective view showing another example of the configuration around the tips of the first end and the second end of the stator coil according to the first embodiment; FIG. 1B is a perspective view showing the state in which the first end and the second end are connected; [Figure 4] 1A is a perspective view showing another example of the configuration around the tips of the first end and the second end of the stator coil according to the first embodiment; FIG. 1B is a perspective view showing the state in which the first end and the second end are connected; [Figure 5] 10A is a perspective view showing an example of a configuration around the tips of a first end and a second end of a stator coil according to a second embodiment; FIG. 10B is a perspective view showing a state in which the first end and the second end are connected; [Figure 6] 10A is a perspective view schematically illustrating another example of the configuration around the tips of the first end and the second end of the stator coil according to the second embodiment, and FIG. 10B is a perspective view illustrating a state in which the first end and the second end are connected. [Figure 7] 10A is a perspective view showing an example of a configuration around the tips of a first end and a second end of a stator coil according to a third embodiment; FIG. 10B is a perspective view showing a state in which the first end and the second end are connected; [Figure 8]10A is a perspective view showing an example of a configuration around the tips of a first end and a second end of a stator coil according to a fourth embodiment; FIG. 10B is a perspective view showing a state in which the first end and the second end are connected; [Figure 9] 10A is a perspective view schematically illustrating another example of the configuration around the tips of the first end and the second end of the stator coil according to the fourth embodiment, and FIG. 10B is a perspective view illustrating a state in which the first end and the second end are connected. [Figure 10] 10A is a perspective view schematically illustrating another example of the configuration around the tips of the first end and the second end of the stator coil according to the fourth embodiment, and FIG. 10B is a perspective view illustrating a state in which the first end and the second end are connected. DETAILED DESCRIPTION OF THE INVENTION

[0008] Stator coils according to several embodiments will be described below with reference to the drawings. Substantially identical elements in each embodiment are designated by the same reference numerals, and descriptions thereof will be omitted. Furthermore, in the following embodiments, the terms "first" and "second" attached to components are intended to simply distinguish between similar components, and do not indicate superiority or inferiority between the components or a time factor. Furthermore, in each drawing, the dimensions of each component may be enlarged as necessary for ease of explanation, and the dimensional ratios between the components may not necessarily be the same as in reality.

[0009] (First embodiment) First, the first embodiment will be described with reference to FIGS. The stator 10 of the embodiment shown in FIG. 1 constitutes a part of a rotating electric machine (not shown) used in an electric vehicle, a hybrid vehicle, or the like. The rotating electric machine is configured, for example, as an inner rotor type. In this case, a rotor (not shown) is provided inside the stator 10 so as to be rotatable relative to the stator 10 via a predetermined gap. The stator 10 is formed, for example, in a substantially cylindrical shape as a whole. In the following description, a direction parallel to the axis of the stator 10 will be referred to as the axial direction. Furthermore, the radial direction of the stator 10 centered on the axis will be simply referred to as the radial direction, and the circumferential direction of the stator 10 centered on the axis will be simply referred to as the circumferential direction.

[0010] The stator 10 has a yoke 11, teeth 12, and a stator coil 20. The yoke 11 and the teeth 12 are formed by stacking, for example, a plurality of flat, annular electromagnetic steel plates. The yoke 11 is formed, for example, in a substantially cylindrical shape as a whole. The teeth 12 are formed extending radially inward from the yoke 11, and are provided at intervals in the circumferential direction. Slots 13 are provided between adjacent teeth 12 in the circumferential direction. The slots 13 are formed to open radially inward. Note that in FIG. 1, to make the drawing easier to understand, only some of the teeth 12 and slots 13 are labeled with reference numerals, and the reference numerals of the remaining teeth 12 and slots 13 are omitted.

[0011] The stator coil 20 is wound around the teeth 12. The stator coil 20 is electrically connected to a control circuit (not shown) via connection terminals, and receives power. The stator coil 20 is formed of a rectangular wire made of a metal material such as a copper alloy or an aluminum alloy. The rectangular wire has a substantially rectangular cross section. The stator coil 20 is composed of a plurality of unit coils 21, each of which has three phases: a U phase, a V phase, and a W phase.

[0012] The plurality of unit coils 21 are assembled and attached so as to be wound around the plurality of teeth 12, respectively. Each unit coil 21 is, for example, an edgewise coil, and has, for example, a thickness of about 3 mm to 5 mm and a width of about 6 mm to 10 mm. In other words, the area of ​​the face of each unit coil 21 along the width direction is larger than the area of ​​the face along the thickness direction.

[0013] The stator coil 20 employs a double star connection, with adjacent unit coils 21 of the same phase connected to each other via a connection portion 22. The unit coils 21 of different phases are connected to each other by a T-connection via a neutral point 23. At the connection portion 22, an end portion 211a of one unit coil 211 and an end portion 212a of the other unit coil 212 are connected to each other.

[0014] The end 211a of one unit coil 211 and the end 212a of the other unit coil 212 are arranged, for example, perpendicular to each other. That is, the side surface on the short side of the end 211a of one unit coil 211 and the side surface on the long side of the end 212a of the other unit coil 212 are positioned opposite each other. Of the unit coils 21 of the same phase connected by the connection portion 22, one unit coil 211 corresponds to one base material, and the other unit coil 212 corresponds to the other base material. In the following description, the end 211a of one unit coil 211 may be referred to as the first end 211a, and the end 212a of the other unit coil 212 may be referred to as the second end 212a. Note that in FIG. 1 , to make the drawing easier to understand, only some of the unit coils 21 and connection portions 22 are indicated by reference numerals, and the reference numerals of the other unit coils 21 and connection portions 22 are omitted.

[0015] At the connection portion 22, the first end portion 211a and the second end portion 212a are directly connected to each other by welding such as TIG welding or laser welding. Direct connection means that the connection is made without using a filler material, for example. In the weld connection at the connection portion 22, the first end portion 211a and the second end portion 212a are in contact with each other, and at least the wide surfaces of the first end portion 211a and the second end portion 212a, i.e., the surfaces along the width direction, are welded to each other.

[0016] Here, the accuracy of positioning the first end 211a and the second end 212a during welding connection affects the quality of the weld, and therefore the quality of the stator coil 20. While it is conceivable to position the first end 211a and the second end 212a using a dedicated jig or the like, this is not preferable from the standpoint of the labor involved. Therefore, in this embodiment, the first end 211a is formed so as to be positionable relative to the second end 212a.

[0017] Specifically, as shown in FIG. 2(a), the first end 211a has a fitting portion 31. The fitting portion 31 is formed, for example, by cutting out both sides of the first end 211a in the thickness direction and forming a convex shape protruding near the center in the thickness direction in the extension direction of the first end 211a. In a plan view, the fitting portion 31 is formed, for example, in a substantially rectangular shape. The fitting portion 31 is formed so that one side and the other side in the width direction have different thicknesses. In this case, one or both of the one side and the other side in the thickness direction of the fitting portion 31 are formed so that they are inclined outward or inward as they move from one side to the other side in the width direction of the fitting portion 31. The tip surface of the fitting portion 31 forms the tip surface in the extension direction of the first end 211a.

[0018] On the other hand, the second end 212a has a mating portion 41. The mating portion 41 is formed so that the mating portion 31 can be mated with it. The mating portion 41 is formed, for example, in a concave shape by cutting out the center of the thickness direction of the second end 212a in the extension direction of the second end 212a. The mating portion 41 is formed, for example, across the entire width of the second end 212a. The shape of the mating portion 41 corresponds to the outer shape of the mating portion 31.

[0019] In this configuration, for example, when the first end 211a is pressed against and brought into contact with the second end 212a, the fitting portion 31 and the fitted portion 41 are fitted together, thereby positioning the first end 211a and the second end 212a relative to each other, as shown in Fig. 2(b). In this case, the fitting portion 31 is fitted into the fitted portion 41, so that movement of the first end 211a or the second end 212a is restricted at least in the thickness direction.

[0020] Then, with the first end 211a and the second end 212a butted against each other, welding is performed on at least one surface and the other surface in the thickness direction of the first end 211a and the second end 212a in an area including the contact portion between the first end 211a and the second end 212a, thereby fixing the unit coil 211 and the unit coil 212. Note that the above-mentioned configuration relating to the connection between the first end 211a and the second end 212a can also be applied to the connection between the unit coil 21 and the neutral point 23. In this case, the fitted portion 41 may be provided on the unit coil 21 and the fitting portion 31 may be provided on one neutral point 23, or vice versa.

[0021] According to the embodiment described above, the stator coil 20 is formed by welding together the wide surfaces of the ends 211 a, 212 a of the plurality of unit coils 211, 212 made of rectangular wire. The end 211 a of one unit coil 211 is arranged perpendicular to the end 212 a of the other unit coil 212, and is formed so as to be positionable relative to the end 212 a of the other unit coil 212.

[0022] This allows the ends 211 a, 212 a of the plurality of unit coils 211, 212 that form part of the stator coil 20 to be easily combined with each other, and also prevents misalignment and loosening during welding connections, etc. This makes it possible to efficiently obtain stable quality of the stator coil 20.

[0023] Moreover, the end 211a of one unit coil 211 has a fitting portion 31. The end 212a of the other unit coil 212 has a fitted portion 41 into which the fitting portion 31 can be fitted. This makes it possible to stably hold the ends 211a, 212a of the multiple unit coils 211, 212 together. This makes it possible to obtain an even more stable quality of the stator coil 20.

[0024] The contact surfaces between the first end 211a and the second end 212a can be configured by fastening. That is, the end 211a of one unit coil 211 and the end 212a of the other unit coil 212 are fastened. In the example of FIG. 3(a), the first end 211a has a first inclined surface 32. The first inclined surface 32 is inclined at a predetermined angle from the tip of the first end 211a toward the base end. The predetermined angle is set to, for example, 45 degrees, but is not limited to this. The first inclined surface 32 is connected to the base end of the fitting portion 31. In this case, the fitting portion 31 is formed in a substantially triangular shape in a plan view. In addition, the tip of the first inclined surface 32 and the tip of the fitting portion 31 are set to be substantially the same position in the extension direction of the first end 211a.

[0025] The second end 212a has a second inclined surface 42. The second inclined surface 42 is inclined from the tip end toward the base end of the second end 212a. The inclination angle of the second inclined surface 42 is set to correspond to the inclination angle of the first inclined surface 32. In this case, the fitted portion 41 has a generally triangular outer shape. In the configuration of this modified example, for example, when the first inclined surface 32 is brought into contact with the second inclined surface 42 so as to coincide with the second inclined surface 42, the fitting portion 31 and the fitted portion 41 are fitted together, as shown in the example of FIG. 3(b), and the first end 211a and the second end 212a are positioned relative to each other. According to this modified example, the ends 211a and 212a of the multiple unit coils 211 and 212 can be smoothly positioned relative to each other.

[0026] FIG. 4 shows another modified example. In this modified example, the fitting portion 31 does not extend to the tip of the first end 211a. That is, the tip of the fitting portion 31 is located closer to the base end of the first end 211a than the tip of the first end 211a. As shown in the example of FIG. 4(a), the fitted portion 41 is not provided across the entire width of the second end 212a, and no fitted portion 41 is formed on the other surface of the second end 212a in the width direction. As shown in the example of FIG. 4(b), when the fitting portion 31 and the fitted portion 41 are fitted together, the fitting portion 31 is housed in the fitted portion 41. In this case, when the fitting portion 31 and the fitted portion 41 are fitted together, movement of the first end 211a or the second end 212a in at least the thickness direction and movement toward the tip in the extension direction are restricted. Therefore, the relative positional relationship between the first end 211a and the second end 212a can be more firmly maintained.

[0027] (Second embodiment) Next, a second embodiment will be described with reference to FIGS. 5 and 6. The second embodiment differs from the first embodiment in the fitting structure between the first end 211a and the second end 212a. Specifically, in the first embodiment, the fitting portion 31 and the fitted portion 41 are provided near the center in the thickness direction of the first end 211a and the second end 212a, respectively. In contrast, in the second embodiment, the stator coil 20 includes a fitting portion 51 and a fitted portion 52, as shown in FIG. 5(a), instead of the fitting portion 31 and the fitted portion 41. For example, the fitting portion 51 and the fitted portion 52 are provided on one surface side in the thickness direction of the first end 211a and the second end 212a, respectively.

[0028] The fitting portion 51 is formed, for example, by cutting out the other surface side in the thickness direction of the first end portion 211a. One surface of the fitting portion 51 is formed on the same plane as one surface of the base end side of the fitting portion 51 at the first end portion 211a. The fitting portion 51 is formed, for example, so as to expand outward from the base end side toward the tip end side of the first end portion 211a. The fitted portion 52 is formed, for example, in the shape of a groove by cutting out one surface side in the thickness direction of the second end portion 212a. The depth dimension of the fitted portion 52 is set to be approximately the same as the thickness of the fitting portion 51. Therefore, as shown in FIG. 5(b), when the fitting portion 51 of the fitted portion 52 is fitted with the fitting portion 51, one surface of the fitting portion 51 and one surface of the fitted portion 52 are arranged on the same plane.

[0029] In such a configuration, when the first end 211a and the second end 212a are positioned relative to each other, for example, the fitting portion 51 is positioned so as to overlap the fitted portion 52 above, and then the first end 211a is moved downward so that the fitting portion 51 fits within the fitted portion 52. Then, by fitting the fitting portion 51 and the fitted portion 52 together, movement of the first end 211a or the second end 212a in at least the extension direction or width direction is restricted.

[0030] The second embodiment also provides the same effects as the first embodiment. Furthermore, by providing the fitting portion 51 and the fitted portion 52 on one side of the first end portion 211a and the second end portion 212a, workability in molding the fitting portion 51 and the fitted portion 52 can be improved.

[0031] The fitting portion 51 may be configured to have a claw portion 51a. The claw portion 51a is intended to prevent the fitting portion 51 from coming off the fitted portion 52. As shown in the example of FIG. 6(a), the claw portion 51a is provided at the tip portion of the fitting portion 51. The claw portion 51a is formed, for example, in a substantially plate shape, and extends outward beyond the other surface of the fitting portion 51 in the thickness direction. A portion of the claw portion 51a faces an end surface 51b located on the base end side of the fitting portion 51.

[0032] 6(b), the second end 212a is sandwiched between the claw portion 51a and the end face 51b. According to this modification, the relative positional relationship between the first end 211a and the second end 212a can be more firmly maintained.

[0033] (Third embodiment) Next, a third embodiment will be described with reference to FIG. 7. This third embodiment differs from the above-described embodiments in the fitting structure between the first end 211a and the second end 212a. Specifically, this third embodiment differs from the above-described embodiments in that, as shown in FIG. 7(a), the first end 211a has a fitting portion 61, and the second end 212a has a fitted portion 62. The fitting portion 61 is formed in a groove shape by cutting out the other surface side in the thickness direction of the first end 211a. The dimension of the fitting portion 61 in the extension direction of the first end 211a is set to be slightly larger than the width dimension of the second end 212a. In this case, the fitting portion 61 is formed across the entire width of the first end 211a.

[0034] The fitted portion 62 is formed in a groove shape by cutting out one surface side in the thickness direction of the second end portion 212a. The dimension of the fitted portion 62 in the extension direction of the second end portion 212a is set to be slightly larger than the width dimension of the first end portion 211a. The shape of the fitted portion 62 is set to be approximately the same as the shape of the fitting portion 61. Then, as shown in FIG. 7(b), when the fitting portion 61 and the fitted portion 62 are fitted together, one surface of the first end portion 211a and one surface of the second end portion 212a are arranged on the same plane.

[0035] The third embodiment also provides the same effects as the above-described embodiments. Furthermore, since the fitting portion 61 and the fitted portion 62 can be configured to have the same shape, design control can be facilitated and the time and effort required for processing the stator coil 20 can be reduced.

[0036] (Fourth embodiment) Next, a fourth embodiment will be described with reference to FIGS. 8 to 10. This fourth embodiment differs from the above-described embodiments in that the first end 211a and the second end 212a are positioned without being fitted together. Specifically, in this fourth embodiment, as shown in FIG. 8(a), the first end 211a has a first shaped portion 71, and the second end 212a has a second shaped portion 72. The first shaped portion 71 and the second shaped portion 72 are located at the distal end side of the first end 211a and the distal end side of the second end 212a, respectively. The first shaped portion 71 is formed by, for example, cutting out one surface of the first end 211a in the thickness direction into a substantially rectangular shape. Therefore, at the first end 211a, the thickness of the first shaped portion 71 is smaller than the thickness of the base end side of the first shaped portion 71. The length of the first shape portion 71 in the extension direction of the first end portion 211a is set to be approximately the same as the width dimension of the second end portion 212a.

[0037] The second shape portion 72 is formed, for example, by cutting out a substantially rectangular portion on the other surface side in the thickness direction of the second end portion 212a. Therefore, at the second end portion 212a, the thickness of the second shape portion 72 is smaller than the thickness of the base end side of the second shape portion 72. The length of the second shape portion 72 in the extension direction of the second end portion 212a is set to be substantially the same as the width dimension of the first end portion 211a.

[0038] In addition, in a plan view, the areas occupied by the first shape portion 71 and the second shape portion 72 are set to be substantially the same. Then, as shown in Fig. 8(b), the first end 211a and the second end 212a are positioned by arranging the first shape portion 71 and the second shape portion 72 so that they overlap in the thickness direction.

[0039] The fourth embodiment also provides the same effects as the first embodiment. Furthermore, by adopting a configuration in which the first end 211a and the second end 212a are not fitted together, high processing precision is not required for the parts related to the positioning of the first end 211a and the second end 212a, which allows for cost reduction.

[0040] In this embodiment, the contact surfaces of the first end 211a and the second end 212a can be configured by fastening. In the example of FIG. 9(a), the first end 211a has a first inclined surface 81. The first inclined surface 81 is inclined at a predetermined angle from the tip of the first end 211a toward the base end. The predetermined angle is set to, for example, 45 degrees, but is not limited to this. The first inclined surface 81 is connected to the base end of the first shape portion 71. In this case, the first shape portion 71 is formed in a substantially triangular shape in a plan view. In addition, the tip of the first inclined surface 81 and the tip of the first shape portion 71 are positioned substantially identically in the extension direction of the first end 211a.

[0041] The second end 212a has a second inclined surface 82. The second inclined surface 82 is inclined from the tip end toward the base end of the second end 212a. The inclination angle of the second inclined surface 82 is set to correspond to the inclination angle of the first inclined surface 81. In this case, the second shape portion 72 has a generally triangular outer shape as a whole. In the configuration of this modified example, for example, when the first inclined surface 81 is brought into contact with the second inclined surface 82, the first shape portion 71 and the second shape portion 72 overlap in the thickness direction, as shown in the example of FIG. 9(b), and the first end 211a and the second end 212a are positioned relative to each other. According to this modified example, the ends 211a and 212a of the multiple unit coils 211 and 212 can be smoothly positioned relative to each other.

[0042] Another modified example is shown in FIG. 10 . In this modified example, as shown in the example of FIG. 10( a), the first end 211a and the second end 212a are configured by omitting the first shaped portion 71 and the second shaped portion 72, respectively. That is, the leading end surface of the first end 211a in the extension direction is configured by a first inclined surface 81. On the other hand, the leading end surface of the second end 212a in the extension direction is configured by a second inclined surface 82. In this case, as shown in the example of FIG. 10( b), when the first inclined surface 81 and the second inclined surface 82 are brought into contact with each other so that they coincide with each other, the first end 211a and the second end 212a are positioned relative to each other. Therefore, the relative positions of the first end 211a and the second end 212a can be adjusted with a simple configuration.

[0043] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as defined in the claims. [Explanation of symbols]

[0044] In the drawing, 20 indicates a stator coil, 211 indicates one unit coil (one base material), 211a indicates a first end (end of one base material), 212 indicates the other unit coil (the other base material), and 212a indicates a second end (end of the other base material).

Claims

1. A stator coil is formed by connecting the wide surfaces at the ends of a plurality of base materials made of rectangular wires by welding, an end portion of one of the base materials is disposed perpendicular to an end portion of the other of the base materials and is formed so as to be positionable with respect to the end portion of the other of the base materials; Stator coil.

2. an end portion of one of the base materials has a fitting portion; an end portion of the other base material has a fitted portion into which the fitting portion can be fitted; The stator coil according to claim 1 .

3. An end portion of one of the base materials and an end portion of the other of the base materials are fastened, respectively.

3. A stator coil according to claim 1 or 2.

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