Rotating machinery and series coil group

Abstract

In the present invention, a first coil (41) is formed by winding a first portion of a rectangular wire in a spiral and is provided on first teeth (36). A second coil (42) is formed by winding a second portion of the rectangular wire in a spiral and is provided on second teeth (37). A crossover (43) is formed with a third portion of the rectangular wire and connects the first coil (41) and the second (42) in series. The third portion of the rectangular wire is continuous with the first portion and the second portion between the first portion and the second portion. The crossover (43) includes a twisted section (44) and an untwisted section (45). In the twisted section (44), the third portion is twisted in the direction of the outer periphery of the third portion. In the second coil (42), the second portion is wound in the same direction as the first portion. A first wire length of the twisted section (44) is set to be equal to or less than a second wire length of the untwisted section (45).

Description

Technical Field

[0001] The present invention relates to a rotating machine such as a motor and a generator, and a series coil group in which two coils are connected in series.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing a stator. The stator is provided in a motor. The manufacturing method includes a forming step, an arranging step, a placing step, and an assembling step. The forming step forms a hollow coil. In the forming step, the processing part bends the coil wire so as to have a designed shape. The processing part includes a conveying part and a deformation part. The conveying part sandwiches the coil wire between two driving rolls and feeds it out from the supply part. The conveying part conveys the coil wire to the deformation part while shaping it linearly in the longitudinal direction. The deformation part includes a pressing roll, a supporting roll, and a pushing roll. The supporting roll is arranged on one side of the conveying path of the coil wire. The pushing roll is arranged on the other side of the conveying path of the coil wire and moves in a direction intersecting the conveying path. The deformation part deforms the coil wire to a desired curvature by the pushing operation of the pushing roll on the coil wire. The coil wire passes through the deformation part and becomes a formed body. The formed body progresses in a spiral shape. In the forming step, the formed body forms a coil unit. The coil unit sequentially arranges a required number of coils and connecting wires. When the stator is a three-phase 12-core, the coil unit includes four concentrated winding coils and five connecting wires. In the coil, straight portions and curved portions are alternately formed. In the coil unit, the connecting wire circulates around the central axis of the coil. The connecting wire has a length required to connect between the coils of the same phase in a state where the coils are arranged. The forming step prepares coil units of U phase, V phase, and W phase.

[0003] The arrangement and placement process arranges the coils of the U-phase, V-phase, and W-phase coil units in a single row according to the following configuration. In the above configuration, when the U-phase, V-phase, and W-phase coil units are assembled in the motor's arrangement order and according to the motor's shape, no crossings occur between the jumper wires. The arrangement and placement process obtains an arranged coil group. In the arranged coil group, all the coils of the U-phase, V-phase, and W-phase coil units are fitted into the coil support. In the arranged coil group, the U-phase jumper wires are located between the W-phase jumper wires and the V-phase jumper wires, the V-phase jumper wires are located between the U-phase jumper wires and the W-phase jumper wires, and the W-phase jumper wires are located between the V-phase jumper wires and the U-phase jumper wires.

[0004] The assembly process involves bringing a segmented stator core, equipped with an insulating member, into contact with the end face of a coil support, and attaching the coils of the coil array to the segmented stator core. The attachment of coils to the segmented stator core is repeated until all coils are attached to multiple segmented stator cores. This process results in a linear stator. Subsequently, the assembly process fixes the linear stator in an annular shape to obtain an annular stator.

[0005] Patent Document 2 discloses a winding structure. The winding structure uses a wire having a rectangular cross-sectional shape. The cross-sectional shape of the rectangular wire is rectangular. The winding structure arranges multiple winding layers in close contact in the thickness direction. The thickness direction of the winding layers is the direction of the long side of the cross-section of the rectangular wire. A space is formed inside the winding structure. A support is inserted into this space, and the winding structure is mounted on this support. The winding layers are made by deforming the rectangular wire so that it curves perpendicular to the short side direction of the cross-section and overlapping them in a spiral shape. "Spiral shape" is a state in which a single wire is stacked so that it overlaps while circling. "Helical shape" is a state in which a single wire is not stacked while circling but is shifted in the thickness direction of the winding layers. The winding layers may also be made by curving the wire in the direction of the long side of the cross-section and overlapping them in a spiral shape.

[0006] The winding layer consists of multiple circumferential sections. Each circumferential section is formed by curving the wire at four perpendicular points, resulting in a rectangular shape with rounded corners when viewed from the thickness direction of the winding layer. The corners of the circumferential section are formed into curved sections with a predetermined curvature. The sides of the circumferential section are formed in a straight line and include a pair of long sides and a pair of short sides. The curvature of the curved sections that form the corners decreases sequentially from the inner circumferential section to the outer circumferential section. Accordingly, the multiple circumferential sections are overlapped so that the wire is in close contact with the entire circumference.

[0007] The winding structure includes a first winding layer and a second winding layer. The first and second winding layers are arranged alternately. In the first winding layer, wire is overlapped in a spiral pattern from the outer circumference to the inner circumference. The first winding layer transitions to the second winding layer by a first connecting section. The first connecting section is formed by wire that is continuous from the inner circumference of the first winding layer. In the second winding layer, wire is overlapped in a spiral pattern from the inner circumference to the outer circumference. The second winding layer transitions to the next first winding layer by a second connecting section. The second connecting section is formed by wire that is continuous from the outer circumference of the second winding layer. The first and second winding layers are arranged in close proximity.

[0008] The wire is deformed spirally by repeatedly passing through two consecutive first and second deformation regions. The first deformation region corresponds to the first winding layer. In the first deformation region, the wire spirals around from the outside to the inside. In the first deformation region, the curvature of the curved portion increases as it moves inward. The second deformation region corresponds to the second winding layer. In the second deformation region, the wire spirals around from the inside to the outside. In the second deformation region, the curvature of the curved portion decreases as it moves outward. At the point where the deformation transitions from the first to the second deformation region, the third deformation point on the second deformation region side abuts against the first deformation point on the first deformation region side. This allows the second winding layer to be formed adjacent to the first winding layer. At the point where the deformation transitions from the second to the first deformation region, the sixth deformation point on the first deformation region side abuts against the fourth deformation point on the second deformation region side. This allows the first winding layer to be formed adjacent to the second winding layer.

[0009] The forming apparatus deforms a wire into a spiral shape. The forming apparatus comprises a conveying mechanism and a deformation mechanism. The conveying mechanism has a drive roller and a driven roller. The drive roller conveys the wire along its longitudinal direction. The driven roller is positioned opposite the drive roller. The deformation mechanism has a push roller, a pivot roller and a press roller. The push roller deforms the wire into a curved shape. The pivot roller is positioned opposite the push roller. The press roller is positioned upstream of the pivot roller in the conveying direction. The wire is held between the drive roller and the driven roller and conveyed while being shaped to become straight in the longitudinal direction. The wire passes between the push roller and the pivot roller while in contact with the press roller. The push roller moves closer to and further away from the pivot roller, performing a pushing motion.

[0010] The molding apparatus continuously conveys the wire while alternately performing a first deformation process and a second deformation process. The first deformation process corresponds to the first deformation region. The first deformation process conveys the wire for the length of the long side corresponding to the outermost circumference, and then forms a curved portion with a predetermined curvature by the pressing action of the pressing roller. Subsequently, the first deformation process conveys the wire for the length of the short side, and then forms a curved portion with a predetermined curvature by the pressing action of the pressing roller. The first deformation process repeatedly performs deformation processing to form the long side portion, the curved portion, the short side portion, and the curved portion. The first deformation process deforms the wire so that it spirals around from the outside to the inside. Furthermore, the first deformation process deforms the wire so that the curvature of the inner curved portion is greater than the curvature of the adjacent outer curved portion.

[0011] The second deformation process corresponds to the second deformation region. After forming the first deformation region, the second deformation process transports the wire by a length corresponding to the first connecting portion. Next, the second deformation process forms a curved portion by a pushing motion with a push roller. Furthermore, the second deformation process transports the wire by a length corresponding to the long side portion corresponding to the innermost circumference, and then forms a curved portion with a predetermined curvature by a pushing motion with a push roller. Subsequently, the second deformation process transports the wire by a length corresponding to the short side portion, and then forms a curved portion with a predetermined curvature by a pushing motion with a push roller. The second deformation process repeatedly performs deformation processing to form the long side portion, curved portion, short side portion, and curved portion. The second deformation process deforms the wire so that it spirals around from the inside to the outside. Furthermore, the second deformation process deforms the wire so that the curvature of the outer curved portion is smaller than the curvature of the adjacent inner curved portion. In the first deformation process after the second deformation process, the wire is moved to the second connecting portion minutes It will transport only the length corresponding to that length.

[0012] In addition, Patent Document 3 discloses a method and apparatus for manufacturing windings. The manufacturing method and apparatus involve deforming a wire into a spiral shape to form a molded body. The molded body is compressed to form a winding. The winding becomes a coil. Furthermore, Patent Document 4 discloses an apparatus and process for deforming conductors protruding from the side surface of a stator or rotor of an electric machine, Patent Document 5 discloses a stator of a rotating electric machine and a method for manufacturing coils in the stator of a rotating electric machine, Patent Document 6 discloses a method for manufacturing stator windings of a rotating electric machine and an apparatus for manufacturing them, and Patent Document 7 discloses a method for manufacturing a coil assembly of a rotating electric machine. [Prior art documents] [Patent Documents]

[0013] [Patent Document 1] Japanese Patent Publication No. 2016-63663 [Patent Document 2] Japanese Patent Publication No. 2014-93846 [Patent Document 3] Japanese Patent Publication No. 2014-93847 [Patent Document 4] Special Publication No. 2022-501986 [Patent Document 5] Japanese Patent Publication No. 2011-188724 [Patent Document 6] Japanese Patent Publication No. 2010-110199 [Patent Document 7] Japanese Patent Publication No. 2009-278708 [Overview of the project] [Problems that the invention aims to solve]

[0014] A rotating machine comprises a coil having the following structure. This structure is formed by concentrated winding of a wire. When the rotating machine is a motor and a generator, the stator includes a stator core and a plurality of coils. The stator core includes a plurality of teeth. The coils are formed by concentrated winding of a wire. The plurality of coils are provided on each of the plurality of teeth. The plurality of coils include a plurality of U-phase coils, a plurality of V-phase coils, and a plurality of W-phase coils. The plurality of coils of the same phase are electrically connected. Furthermore, two coils of the same phase may be connected in series and provided on two teeth that are adjacent in the circumferential direction.

[0015] Flat rectangular wire is sometimes used as the conductor for forming coils. In its raw state before winding, flat rectangular wire has a rectangular cross-sectional shape. Forming coils with flat rectangular wire can sometimes improve the space factor. This improvement in space factor can lead to higher efficiency in rotating machinery. Such coils can be used not only in rotating machinery but also in transformers.

[0016] Assume the coils are made of flat rectangular wire. Welding can be used to connect coils of the same phase. However, the inventor focused on the fact that if welding is used to connect coils of the same phase, quality control of the welded joint will be necessary. That is, the inventor considered it necessary to control whether connection defects occur in the welded joint. Furthermore, the inventor focused on the fact that if welding is used to connect coils of the same phase, the stator tends to become larger. That is, the inventor considered that if the following spaces need to be secured in the stator, the stator will become larger by the amount of this space. Examples of the aforementioned spaces include the space for arranging the two flat rectangular wires to be connected, the space required for the welding torch, and the space to prevent the heat during welding from affecting surrounding parts. Therefore, the inventor considered a coil structure made of flat rectangular wire that is less prone to electrical connection defects between two coils of the same phase and can suppress the enlargement of the stator. In doing so, the inventor considered how to improve the productivity of coils made of flat rectangular wire. Furthermore, the inventor also considered the possibility of accommodating a stator structure in which two coils made of flat wire are connected in series, and these two coils are provided on two teeth adjacent to each other in the circumferential direction.

[0017] This invention provides a technology that can improve the productivity of two series-connected coils made of flat wire while suppressing an increase in the size of the stator. [Means for solving the problem]

[0018] One aspect of the present invention comprises a rotor and a stator, the stator being formed by laminating steel plates and including a stator core including a yoke and a plurality of teeth protruding from the yoke toward the rotor side, a first coil formed by spirally winding a first portion of a rectangular wire and provided on the first tooth of the plurality of teeth, a second coil formed by spirally winding a second portion of the rectangular wire and provided on the second tooth of the plurality of teeth, and a jumper wire formed by a third portion of the rectangular wire connecting the first and second portions between the first and second portions and connecting the first and second coils in series, The first teeth are adjacent to the second teeth in the circumferential direction with respect to the rotation axis of the rotor, The bypass line includes a twisted portion obtained by twisting the third portion forming the bypass line in the outer circumferential direction of the third portion, and a non-twisted portion excluding the twisted portion. The second coil winds the second portion in a spiral shape in the same direction as the first portion. The connecting wire connects the first coil and the second coil in series such that the flow of electricity in the second coil is in the opposite direction to the flow of electricity in the first coil, and the twisted portion is provided in the region of the connecting wire along the lamination direction in which the steel plates are laminated, in the state of the stator in which the first coil is provided on the first teeth and the second coil is provided on the second teeth. A rotating machine, wherein a first line length of the twisted portion in the length direction of the straight angle line is set to be not more than a second line length of the non-twisted portion in the length direction.

[0019] The stator is formed by a fourth portion of the straight angle line that is continuous with the side opposite to the third portion of the first portion. The lead wire is provided on the first side in the lamination direction from a first end surface on the first side in the lamination direction of the stator core. The bypass line may be provided on the second side in the lamination direction from a second end surface on the second side opposite to the first side in the lamination direction of the stator core. Accumulation It may be configured as such.

[0020] The yoke includes a plurality of yoke pieces and is formed by assembling the plurality of yoke pieces in a ring shape, and the first teeth and the second teeth protrude from the first yoke piece of the plurality of yoke pieces toward the rotor side. It may be configured as such.

[0021] Another aspect of the present invention is formed by winding a first portion of a straight angle line in a spiral shape, and is provided on a first tooth among a plurality of teeth provided on a stator core of a rotating machine. In the circumferential direction centered on the rotor's axis of rotation, the rotating machine A first coil, a second coil formed by winding a second portion of the straight angle line in a spiral shape and provided on a second tooth, and a bypass line formed by a third portion of the straight angle line that is continuous with the first portion and the second portion between the first portion and the second portion, and connecting the first coil and the second coil in series. The bypass line includes a twisted portion obtained by twisting the third portion forming the bypass line in the outer circumferential direction of the third portion, and a non-twisted portion excluding the twisted portion. The second coil winds the second portion in a spiral shape in the same direction as the first portion. Among the multiple teeth adjacent to the second tooth A series coil group, wherein a first line length of the twisted portion in the length direction of the straight angle line is set to be not more than a second line length of the non-twisted portion in the length direction. Record number The connecting wire connects the first coil and the second coil in series such that the flow of electricity in the second coil is in the opposite direction to the flow of electricity in the first coil, and the twisted portion is provided in the region of the connecting wire along the lamination direction in which the steel plates forming the stator core are laminated, in the state of the stator in which the first coil is provided on the first teeth and the second coil is provided on the second teeth.

[0022] ​​The above-described rotating machine and series coil group make it possible to easily manufacture the first and second coils connected by jumper wires. After winding a single continuous rectangular wire, the third portion of this rectangular wire is twisted at the position where the twisted portion of the rectangular wire is located, thereby forming the first and second coils connected by jumper wires. The winding and connecting processes for the first and second coils can be simplified. [Effects of the Invention]

[0023] According to the present invention, it is possible to improve the productivity of two coils made of flat wire connected in series while suppressing an increase in the size of the stator. [Brief explanation of the drawing]

[0024] [Figure 1] This is a perspective view showing an example of the schematic configuration of a motor as a rotating machine. The motor is shown as viewed from the first side in the stacking direction. [Figure 2] This is a plan view showing an example of a motor's schematic configuration. [Figure 3] This is a perspective view showing an example of the schematic configuration of a rotor. The rotor is shown as viewed from the first side in the stacking direction. [Figure 4] This is a perspective view showing an example of the stator's schematic configuration. The stator is shown as viewed from the first side in the stacking direction. [Figure 5] This is a perspective view showing an example of the stator's schematic configuration. The stator is shown as viewed from the second side in the stacking direction. [Figure 6] This is a perspective view showing an example of the schematic configuration of the yoke pieces, teeth, coil, and insulating members. The yoke pieces, teeth, coil, and insulating members are shown as viewed from the first side in the stacking direction. [Figure 7] This is a perspective view showing an example of the schematic configuration of the yoke piece, teeth, coil, and insulating member. The teeth, coil, and insulating member are shown in an assembled state. The yoke piece and the assembly of teeth, coil, and insulating member are shown as viewed from the first side in the stacking direction. [Figure 8]This is a perspective view showing an example of the schematic configuration of a part of the stator. It shows a portion of the stator viewed from the first side in the stacking direction. [Figure 9] This is a perspective view showing an example of the general structure of a rectangular wire. The rectangular wire is shown in its raw state before winding. The first, second, third, fourth, and fifth parts of the rectangular wire are shown, with the intermediate sections omitted in each of the first, second, third, fourth, and fifth parts. [Figure 10] This is a wiring diagram showing an example of how multiple coils are connected. [Figure 11] This is a perspective view showing an example of the schematic configuration of the intermediate and series coil group. It shows the intermediate and series coil group viewed from the first side in the stacking direction. The second step of the manufacturing method for the series coil group is shown. [Modes for carrying out the invention]

[0025] Embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the configurations described below, and various configurations can be adopted within the same technical concept. For example, some of the configurations shown below may be omitted or replaced with other configurations. The present invention may include other configurations. The drawings schematically show a predetermined configuration. Each drawing may not correspond accurately to other drawings or to the numerical values ​​that specify the configuration in the drawings, as described later.

[0026] <Motor 10> The motor 10 as a rotating machine will be described with reference to Figures 1 to 11. The motor 10 is mounted on various products. For example, the motor 10 is used as a power source for electric vehicles. Examples of electric vehicles include electric cars, electric bicycles, electric wheelchairs, electric carts, and electric food service carts. Electric cars include hybrid vehicles. The motor 10 comprises a rotor 20 and a stator 30 (see Figures 1 and 2). In this embodiment, an internal rotation type brushless motor is exemplified as the motor 10.

[0027] The rotor 20 comprises a rotor core 21, a plurality of permanent magnets, and a shaft 22 (see Figures 2 and 3). In Figures 2 and 3, the permanent magnets are not shown. For example, the rotor core 21 is formed by punching out steel sheets with a press and stacking the punched-out steel sheets. Electromagnetic steel sheets are used as the steel sheets. The rotor core 21 is provided with a plurality of permanent magnets. The plurality of permanent magnets are housed in a plurality of spaces formed in the rotor core 21. When the rotor 20 is of this type, the motor 10 is called an IPM (Interior Permanent Magnet) motor. The plurality of permanent magnets may also be provided on the outer circumferential surface of the rotor core 21. When the rotor 20 is of this type, the motor 10 is called an SPM (Surface Permanent Magnet) motor.

[0028] The shaft 22 is fixed to a through hole formed in the center of the rotor core 21. Bearings are attached to the shaft 22 on both sides of the rotor core 21. The bearings are supported by a support. For example, the support is provided on the stator 30 or on the housing that supports the stator 30. In Figures 1 and 2, the bearings, support and housing are not shown. In this embodiment, the circumferential direction centered on the shaft 22 is called the "circumferential direction," and the radial direction centered on the shaft 22 is called the "radial direction." The shaft 22 is the axis of rotation of the rotor 20. The rotor 20 rotates in the circumferential direction around the shaft 22. The rotor 20 is similar to the rotors of known motors (rotating machines). Therefore, further explanation of the rotor 20 is omitted.

[0029] The stator 30 comprises a stator core 31 and a plurality of coils 40 (see Figures 2, 4, and 5). Furthermore, the stator 30 comprises an insulating member 70 (see Figure 6). In Figure 2, the illustration of the coils 40 is simplified, and in Figures 1, 4, and 5, the illustration of the insulating member 70 is omitted. The stator core 31 includes a yoke 32 and a plurality of teeth 35 (see Figures 2, 4, and 5). In the internal rotation type motor 10, the plurality of teeth 35 protrude radially inward on the inner circumference of the yoke 32. The stator core 31 has the same number of slots 38 as the teeth 35 (see Figure 2). A slot 38 is a space formed between adjacent teeth 35. The number of slots 38 in the stator 30 is appropriately determined considering the following points. An example of the aforementioned points is the performance required for the motor 10.

[0030] In this embodiment, the stator core 31 has a divided structure in which the yoke 32 and a plurality of teeth 35 are divided (see Figures 2, 4 to 8). The number of teeth 35 is 12 (see Figure 2). In this case, the number of slots 38 is 12. In the stator core 31, the 12 teeth 35 are provided at equal angular intervals. In other words, the 12 teeth 35 are equally spaced at 30° intervals in the circumferential direction. The yoke 32 has a configuration in which it is equally divided into 6 yoke pieces 33. Each yoke piece 33 is provided with 2 teeth 35 (see Figures 2, 4, 5, 7, 8). The stator core 31 is formed by mounting 2 teeth 35 on one yoke piece 33 and assembling the 6 yoke pieces 33 in a ring shape (see Figures 2, 4 to 8). The number of teeth 35, the number of divisions of the ring-shaped yoke 32, and the number of teeth 35 per yoke piece 33 may differ from those in this embodiment. These numbers in the embodiments are illustrative examples.

[0031] The yoke piece 33 includes a mounting groove 34 (see Figures 2, 6-8). The mounting groove 34 is located on the radially inner side where the teeth 35 are provided. The radially outer ends of the teeth 35 are fitted into the mounting groove 34 (see Figures 2, 8). In Figures 1, 4, and 5, the illustration of the stator core 31 is simplified, and the illustration of the fitting structure of the yoke piece 33 and teeth 35 is omitted. The yoke piece 33 may have a first engaging portion on the inner surface of the mounting groove 34, and the teeth 35 may have a second engaging portion on its radially outer end. The second engaging portion engages with the first engaging portion. That is, the teeth 35 are mounted on the yoke piece 33 with their radially outer ends engaged with the inner surface of the mounting groove 34. In this embodiment, the illustration of the first and second engaging portions is omitted.

[0032] For example, the yoke pieces 33 and teeth 35 are formed by punching out steel sheets with a press and then stacking the punched-out steel sheets. Electrical steel sheets are used as the steel sheets. In this embodiment, the direction in which the steel sheets are stacked in the yoke pieces 33 and teeth 35 is called the "stacking direction". When the stator core 31 is formed from multiple yoke pieces 33 and multiple teeth 35 (see Figures 2, 4 to 8), the stacking direction can also be said to be the direction in which the steel sheets are stacked in the stator core 31. The stacking direction coincides with the direction in which the steel sheets are stacked in the rotor core 21. Assume that the yoke piece 33 includes a first engagement portion on the inner surface of the mounting groove 34, and the teeth 35 include a second engagement portion at the radial outer end. In this case, the teeth 35 may be attached to the yoke piece 33 from either the first or second side in the stacking direction.

[0033] The coil 40 is formed from flat rectangular wire. The surface of the flat rectangular wire is covered with a coating. An example of a conductor is copper. An example of a coating is an insulating coating. The insulating coating has electrical insulating properties. The flat rectangular wire and conductor have a rectangular cross-sectional shape in their raw material state before winding (see Figure 9). The width and thickness of the cross-sectional shape of the flat rectangular wire are referred to as the "first width" and "first thickness," and the width and thickness of the cross-sectional shape of the conductor of the flat rectangular wire are referred to as the "second width" and "second thickness" (see Figure 9). Examples of the first width and first thickness of the flat rectangular wire include 2.83 mm and 1.63 mm, examples of the second width and second thickness of the conductor include 2.7 mm and 1.5 mm, and an example of the thickness of the coating is 0.065 mm. The circumference of a rectangular wire with a first width and first thickness of 2.83 mm and 1.63 mm is 8.92 mm, and the circumference of a conductor with a second width and second thickness of 2.7 mm and 1.5 mm is 8.4 mm. In this embodiment, the circumference of the rectangular wire is defined as twice the sum of the first width and first thickness, and the circumference of the conductor is defined as twice the sum of the second width and second thickness.

[0034] The first width and first thickness of the rectangular wire, the second width and second thickness of the conductor, and the thickness of the coating may differ from the values ​​described above. The first width and first thickness of the rectangular wire, the second width and second thickness of the conductor, and the thickness of the coating are determined appropriately considering various conditions. For example, the second width and second thickness of the conductor may be 2.0 mm and 0.7 mm, or 6.5 mm and 3.5 mm. The circumference of a conductor with a second width and second thickness of 2.0 mm and 0.7 mm is 5.4 mm. The circumference of a conductor with a second width and second thickness of 6.5 mm and 3.5 mm is 20 mm. In the case of rectangular wire, the circumference of the conductor may be between 5.4 and 20 mm. Examples of standards for rectangular wire include JIS C3215-0-2 (Common standards for windings - Part 0-2: General characteristics - Enameled rectangular copper wire) and JIS C3104 (Rectangular copper wire).

[0035] The multiple coils 40 are classified into U-phase, V-phase, and W-phase (see Figure 10). In this embodiment, the U-phase coil 40 is called "coil 40U", the V-phase coil 40 is called "coil 40V", and the W-phase coil 40 is called "coil 40W". The stator 30 includes multiple coils 40U as U-phase coils 40, multiple coils 40V as V-phase coils 40, and multiple coils 40W as W-phase coils 40. The multiple coils 40U are connected to each other to form a U-phase coil unit 51U. The multiple coils 40V are connected to each other to form a V-phase coil unit 51V. The multiple coils 40W are connected to each other to form a W-phase coil unit 51W.

[0036] The coil unit 51U connects at least two coils 40U in series with a jumper wire 43U. The multiple coils 40U and jumper wire 43U connected in series are integrally formed by a single continuous flat wire. In this embodiment, the connected body (connection structure) of the multiple coils 40U connected in series by the jumper wire 43U is called the "series coil group 50U". In the series coil group 50U, the portions at both ends of this single flat wire are drawn out to a predetermined length. In this embodiment, these drawn-out portions of the flat wire are called "leader wires 46U, 47U". In this single flat wire, the portion at one end forms the leader wire 46U, and the portion at the other end forms the leader wire 47U.

[0037] The coil unit 51V connects at least two coils 40V in series with a jumper wire 43V. The multiple coils 40V and jumper wire 43V connected in series are integrally formed by a single continuous flat wire. In this embodiment, the connected body (connection structure) of the multiple coils 40V connected in series by the jumper wire 43V is called the "series coil group 50V". In the series coil group 50V, the portions at both ends of this single flat wire are drawn out to a predetermined length. In this embodiment, these drawn-out portions of the flat wire are called "leader wires 46V, 47V". In this single flat wire, the portion at one end forms the leader wire 46V, and the portion at the other end forms the leader wire 47V.

[0038] The coil unit 51W connects at least two coils 40W in series with a jumper wire 43W. The multiple coils 40W and jumper wire 43W connected in series are integrally formed by a single continuous flat wire. In this embodiment, the connected body (connection structure) of the multiple coils 40W connected in series by the jumper wire 43W is called the "series coil group 50W". In the series coil group 50W, the portions at both ends of this single flat wire are drawn out to predetermined lengths. In this embodiment, these drawn-out portions of the flat wire are called "leader wires 46W, 47W". In this single flat wire, the portion at one end forms the leader wire 46W, and the portion at the other end forms the leader wire 47W.

[0039] In this embodiment, the stator 30 includes four coils 40U, four coils 40V, and four coils 40W (see Figure 10). In the stator 30, the four coils 40U are connected to form a coil unit 51U, the four coils 40V are connected to form a coil unit 51V, and the four coils 40W are connected to form a coil unit 51W. The stator 30 includes coil units 51U, 51V, and 51W.

[0040] In the coil unit 51U, two sets of four coils 40U are connected in series by jumper wires 43U to form a series coil group 50U. The stator 30 includes two sets of series coil groups 50U in the coil unit 51U. The two sets of series coil groups 50U are connected to each other by two lead wires 46U and to each other by two lead wires 47U. The two sets of series coil groups 50U are connected in parallel.

[0041] In coil unit 51V, four 40V coils are connected in series in pairs by jumper wires 43V to form a series coil group 50V. The stator 30 includes two series coil groups 50V in the coil unit 51V. The two series coil groups 50V are connected by two lead wires. 46V They are connected to each other, with the two 47V lead wires connected to each other. The two sets of 50V series coils are connected in parallel.

[0042] In the 51W coil unit, four 40W coils are connected in series in pairs by jumper wires of 43W to form a 50W series coil group. The stator 30 includes two 50W series coil groups in the 51W coil unit. The two 50W series coil groups are connected to each other by two 46W lead wires, and to each other by two 47W lead wires. The two 50W series coil groups are connected in parallel.

[0043] However, the connection configurations of the multiple coils 40U, the multiple coils 40V, and the multiple coils 40W may differ from those shown in Figure 10. The multiple coils 40U may all be connected in series. The multiple coils 40V may all be connected in series. The multiple coils 40W may all be connected in series. The connection configurations of the multiple coils 40U, the multiple coils 40V, and the multiple coils 40W are determined appropriately considering various conditions. In the stator 30, the coil units 51U, 51V, and 51W are delta connected (see Figure 10). However, the connection configuration of the coil units 51U, 51V, and 51W does not have to be delta connected. An example of a connection configuration other than delta connection is a star connection. The connection configuration of the coil units 51U, 51V, and 51W are determined appropriately considering various conditions.

[0044] In this embodiment, when coils 40U, 40V, and 40W are not distinguished or are referred to collectively, they are referred to as "coil 40". When coil units 51U, 51V, and 51W are not distinguished or are referred to collectively, they are referred to as "coil unit 51". When jumper wires 43U, 43V, and 43W are not distinguished or are referred to collectively, they are referred to as "jumper wire 43". When lead wires 46U, 46V, and 46W are not distinguished or are referred to collectively, they are referred to as "leader wire 46". When lead wires 47U, 47V, and 47W are not distinguished or are referred to collectively, they are referred to as "leader wire 47". When series coil groups 50U, 50V, and 50W are not distinguished or are referred to collectively, they are referred to as "series coil group 50". When two coils 40 in the series coil group 50 are distinguished, they are referred to as "first coil 41" and "second coil 42". When distinguishing between the teeth 35 on which the first coil 41 is provided and the teeth 35 on which the second coil 42 is provided, they are referred to as "first tooth 36" and "second tooth 37". The first tooth 36 is provided with the first coil 41, and the second tooth 37 is provided with the second coil 42 (see Figures 2, 4, 5, 7, and 8). The first tooth 36 is adjacent to the second tooth 37 in the circumferential direction. In this embodiment, the first tooth 36 and the second tooth 37 are provided on the same yoke piece 33. Coil 40, first coil 41, second coil 42, jumper wire 43, lead wire 46 ,47 The series coil group 50 and the coil unit 51 are composed of elements of the same phase.

[0045] The coil 40 is provided on the teeth 35 via an insulating member 70 (see Figures 2, 6 to 8). In the stator 30, multiple coils 40 are provided on multiple teeth 35 in the following state (see Figures 4 and 5). In this state, the first coil 41 is provided on the first tooth 36 of the multiple teeth 35, and the second coil 42 is provided on the second tooth 37 of the multiple teeth 35 (see Figures 2, 4, 5, 7, and 8).

[0046] The coil 40 includes coil ends on the first and second sides in the stacking direction. The coil end on the first side in the stacking direction does not house in the slot 38 but protrudes to the first side in the stacking direction from the end face of the stator core 31 in the stacking direction (see Figures 4 and 8). The coil end on the second side in the stacking direction does not house in the slot 38 but protrudes to the second side in the stacking direction from the end face of the stator core 31 in the stacking direction (see Figure 5). The coil 40 includes connecting portions on both sides in the circumferential direction. The connecting portions on both sides in the circumferential direction connect the coil ends on the first and second sides in the stacking direction and are housed in the slots 38 on both sides in the circumferential direction of the teeth 35, respectively (see Figures 6 to 8). The connecting portions of the coil 40 have a shape aligned with the stacking direction.

[0047] The coil 40 includes multiple coil layers 55 (see Figures 6 and 11, right side). In this embodiment, the coil 40 includes four coil layers 55. The number of coil layers 55 provided in the coil 40 may be 1 to 3, or 5 or more. The number of coil layers 55 in the coil 40 is determined appropriately considering various conditions. The coil layers 55 have a structure in which flat wire is wound in a spiral shape. The number of turns of the flat wire may be different or the same for some or all of the multiple coil layers 55. The number of turns of the flat wire in the multiple coil layers 55 is determined appropriately considering various conditions. Two adjacent coil layers 55 are connected by the flat wire that forms the coil 40 on the inner or outer circumference side of the coil 40.

[0048] The coil 40 can employ the structure disclosed in Patent Documents 2 and 3 for the coil layer 55. Therefore, further explanation regarding the structure of the coil layer 55 is omitted. In the embodiments, the coil layer 55 shown in Figure 6 and the right side of Figure 11 is denoted by the reference numeral "55", while the reference numeral "55" is omitted in Figures 1, 2, 4, 5, 7, 8, and 10.

[0049] The insulating member 70 has electrical insulating properties and electrically insulates the teeth 35 and the coils 40. That is, in the stator 30, the multiple coils 40 are electrically insulated from the stator core 31 by the insulating member 70. In this embodiment, the insulating member 70 is provided on both sides of the teeth 35 in the circumferential direction within the slot 38 (see Figures 2, 6 to 8). In this case, the insulating member 70 is referred to as slot insulating paper. Slot insulating paper is also used in the stators of known motors (rotating machines). In addition, the stator 30 may employ the following insulating structure. This insulating structure includes an insulator. The insulator may be a resin molded product. Insulators have already been put into practical use and are used in known stators. The stator 30 can employ an insulating structure that includes an insulating member similar to such known stators. The stator 30 may employ an insulating structure that includes both slot insulating paper and an insulator. Therefore, further explanation regarding the following points is omitted. The points mentioned above relate to the insulating member 70. Furthermore, the aforementioned points relate to the electrical insulation structure of the stator core 31 and coil 40 using the insulating member 70.

[0050] <Series coil group 50 and manufacturing method of series coil group 50> The series coil group 50 and the manufacturing method of the series coil group 50 will be described with reference to Figures 4 to 11. The series coil group 50 includes a first coil 41, a second coil 42, a jumper wire 43, and lead wires 46, 47 (see Figures 4 to 8, 10 and the right side of Figure 11). The series coil group 50 is formed by a single continuous rectangular wire. In this embodiment, the single rectangular wire forming the series coil group 50 is divided into a "first part," a "second part," a "third part," a "fourth part," and a "fifth part" (see Figure 9). The first part of the rectangular wire forms the first coil 41. The second part of the rectangular wire forms the second coil 42. The third part of the rectangular wire is connected to the first and second parts of the rectangular wire. The third part of the rectangular wire forms the jumper wire 43. The fourth part of the rectangular wire is connected to the side of the first part of the rectangular wire opposite to the third part. The fourth part of the rectangular wire forms the lead wire 46. The fifth section of the rectangular conductor connects to the opposite side of the third section of the second section of the rectangular conductor. The fifth section of the rectangular conductor forms a leader line 47.

[0051] The first coil 41 is formed by winding the first portion of a flat wire in a spiral shape, and the second coil 42 is formed by winding the second portion of a flat wire in a spiral shape (see Figures 9 and 11, right side). The radial direction is either inner or outer. In this case, the direction in which the second portion of the flat wire is wound in the second coil 42 is the same as the direction in which the first portion of the flat wire is wound in the first coil 41. In contrast, the flow of electricity in the second coil 42 is in the opposite direction to the flow of electricity in the first coil 41.

[0052] In this embodiment, with the radially inner side as the reference, the first portion of the rectangular wire is wound clockwise in the first coil 41 from the side of the jumper wire 43 toward the side of the lead wire 46, and the second portion of the rectangular wire is wound clockwise in the second coil 42 from the side of the jumper wire 43 toward the side of the lead wire 47. For example, suppose that electricity flows from the side of the lead wire 46 toward the side of the lead wire 47. In this case, with the radially inner side as the reference, the electricity flows counterclockwise in the first coil 41 from the side of the lead wire 46 toward the side of the jumper wire 43, and the electricity flows clockwise in the second coil 42 from the side of the jumper wire 43 toward the side of the lead wire 47. In this embodiment, the side of the jumper wire 43 is the radially inner side, and the sides of the lead wires 46 and 47 are the radially outer side.

[0053] The jumper wire 43 connects the first coil 41 and the second coil 42 in series (see Figures 6, 10 and the right side of Figure 11). The jumper wire 43 is provided on the second side in the stacking direction from the second end face in the stacking direction of the stator core 31 in the following state (see Figures 5, 7, and 8). In this state, the first coil 41 is provided on the first tooth 36, and the second coil 42 is provided on the second tooth 37. In this embodiment, the first end face in the stacking direction of the stator core 31 is referred to as the "first end face of the stator core 31," and the second end face in the stacking direction of the stator core 31 is referred to as the "second end face of the stator core 31." The first end face of the stator core 31 includes the first end face in the stacking direction of the yoke 32 and the first end faces in the stacking direction of the plurality of teeth 35. The first end face in the stacking direction of the yoke 32 is formed by the first end faces of the plurality of yoke pieces 33 arranged in an annular shape. The second end face of the stator core 31 includes the second end face of the yoke 32 in the stacking direction and the second end faces of the plurality of teeth 35 in the stacking direction. The second end face of the yoke 32 in the stacking direction is formed by the second end faces of the plurality of annularly arranged yoke pieces 33.

[0054] The connecting wire 43 includes a twisted portion 44 and an untwisted portion 45 (see Figures 6-8 and the right side of Figure 11). The twisted portion 44 has a shape in which the third portion of the rectangular wire is twisted in the direction of the outer circumference of this third portion. The twisted portion 44 is formed by twisting the third portion of the rectangular wire in the direction of the outer circumference of this third portion (see Figure 11). The twist angle (θ) of the rectangular wire is calculated by the following equation (1). In equation (1), "N" is the number of teeth 35 (number of slots 38).

[0055] θ = 180° - 360° / N ···(1) In this embodiment, the number of teeth 35 is 12. In this case, the twist angle (θ) of the twisted portion 44 in the series coil group 50 is 150°. The twisted portion 44 is provided in the second region of the jumper wire 43. The second region of the jumper wire 43 is connected to the second coil 42 and runs along the stacking direction in the stator 30 state. The untwisted portion 45 is the portion of the jumper wire 43 excluding the twisted portion 44. The untwisted portion 45 is provided in the first, second, and third regions of the jumper wire 43. The first region of the jumper wire 43 is connected to the first coil 41 and runs along the stacking direction in the stator 30 state. The third region of the jumper wire 43 connects the first and second regions of the jumper wire 43 and runs along the second end face of the stator core 31 in the stator 30 state. The jumper wire 43 has non-twisted portions 45 between the first coil 41 and the twisted portion 44, and between the twisted portion 44 and the second coil 42 (see Figures 6-8 and the right side of Figure 11). However, the jumper wire 43 may also have a twisted portion 44 at the side end of the second coil 42 in the second region of the jumper wire 43. The position of the twisted portion 44 in the jumper wire 43 is determined appropriately considering various conditions. The side end of the second coil 42 in the second region of the jumper wire 43 forms the side end of the second coil 42 of the jumper wire 43.

[0056] The first length of the twisted portion 44 in the longitudinal direction of the rectangular wire (see Figure 9) is set to be less than or equal to the second length of the untwisted portion 45 in the longitudinal direction. The first length of the twisted portion 44 may be less than or equal to twice the circumference of the conductor of the rectangular wire, or less than or equal to once. The first length of the twisted portion 44 may be greater than or equal to the second thickness of the conductor of the rectangular wire, or greater than or equal to the second width of the conductor of the rectangular wire. The first length of the twisted portion 44 may be less than or equal to twice the circumference of the rectangular wire, or less than or equal to once. The first length of the twisted portion 44 may be greater than or equal to the first thickness of the rectangular wire, or greater than or equal to the first width of the rectangular wire. It is preferable that the first length of the twisted portion 44 be such that no damage occurs to the rectangular wire due to twisting when the rectangular wire is twisted. Examples of damage that may occur in a flat wire include scratches on the coating, cracks in the coating, scratches on the conductor, and cracks in the conductor. Cracks include fractures. For example, the first wire length of the twisted portion 44 is preferably determined by considering the shear stress acting on the third portion of the flat wire when the twisted portion 44 is formed (when the third portion of the flat wire is twisted). For example, when the twisted portion 44 is formed, it is preferable that the shear stress acting on the third portion of the flat wire is less than the shear stress of the conductor. The first wire length of the twisted portion 44 is determined appropriately by considering various conditions. It is preferable that the first wire length of the twisted portion 44 is set to the length described above, and that it is provided in the second region of the jumper wire 43, and not in the first and third regions of the jumper wire 43.

[0057] The lead wires 46 and 47 are provided on the first side in the stacking direction from the first end face of the stator core 31 in the following state (see Figures 4, 7, and 8). In this state, the first coil 41 is provided on the first tooth 36, and the second coil 42 is provided on the second tooth 37. The lead wires 46 and 47 are drawn out on the first side in the stacking direction from the first end face of the stator core 31 in the aforementioned state. Lead wire 46 is connected to the first coil 41 on the side opposite to the jumper wire 43 of the first coil 41, and lead wire 47 is connected to the second coil 42 on the side opposite to the jumper wire 43 of the second coil 42 (see Figure 10).

[0058] The manufacturing method for the series coil group 50 includes a first step and a second step. The first step is to form an intermediate body 60. The intermediate body 60 is formed by winding a single flat wire in a spiral shape and is formed into the series coil group 50 through the second step. The intermediate body 60 includes a first assembly 61, a second assembly 62, a connecting wire 63, and lead wires 46 and 47 (see left side of Figure 11). In this embodiment, in order to clarify the correspondence with the series coil group 50 in the stator 30, the "stacking direction" is used as the direction that identifies the intermediate body 60.

[0059] The first assembly 61 corresponds to the first coil 41 and contains the same number of coil layers as the coil layers 55 of the first coil 41. The multiple coil layers in the first assembly 61 are connected by a flat wire that forms the first assembly 61 on either the inner or outer circumference side of the first assembly 61. The first step is to form the first assembly 61, which contains multiple continuous coil layers, by the first part of the flat wire (see Figure 9). The second assembly 62 corresponds to the second coil 42 and contains the same number of coil layers as the coil layers 55 of the second coil 42. The multiple coil layers in the second assembly 62 are connected by a flat wire that forms the second assembly 62 on either the inner or outer circumference side of the second assembly 62. The first step is to form the second assembly 62, which contains multiple continuous coil layers, by the second part of the flat wire (see Figure 9). In Figure 11, the accuracy of the number of coil layers in the first assembly 61 and the number of coil layers 55 in the first coil 41, as well as the accuracy of the number of coil layers in the second assembly 62 and the number of coil layers 55 in the second coil 42, are not considered.

[0060] The connecting wire 63 corresponds to the jumper wire 43. The first step is to form the connecting wire 63 using the third portion of the rectangular wire (see Figure 9). In this embodiment, the region of the connecting wire 63 that corresponds to the second region of the jumper wire 43 is called the "second region R2 of the connecting wire 63" (see left side of Figure 11). The second region R2 of the connecting wire 63 is connected to the second assembly 62 and is provided in the stacking direction. The connecting wire 63 differs from the jumper wire 43 in that it does not include the twisted portion 44, but is otherwise the same as the jumper wire 43. The lead wire 46 of the intermediate body 60 corresponds to the lead wire 46 of the series coil group 50. The lead wire 47 of the intermediate body 60 corresponds to the lead wire 47 of the series coil group 50. The first step is to form the lead wire 46 of the intermediate body 60 using the fourth portion of the rectangular wire (see Figure 9), and to form the lead wire 47 of the intermediate body 60 using the fifth portion of the rectangular wire (see Figure 9).

[0061] The first step can employ the methods disclosed in the aforementioned Patent Documents 2 and 3. Specifically, the first step involves unwinding the rectangular wire material in the length direction of the rectangular wire (see Figure 9) and deforming it into a spiral shape, thereby forming an intermediate body 60 that includes multiple coil layers in which the rectangular wire is wound in a spiral shape. The first step forms the intermediate body 60 continuously in the order of lead wire 46, multiple coil layers of the first assembly 61, connecting wire 63, multiple coil layers of the second assembly 62 and lead wire 47, or continuously in the order of lead wire 47, multiple coil layers of the second assembly 62, connecting wire 63, multiple coil layers of the first assembly 61 and lead wire 46. The first step manufactures the intermediate body 60 using a winding device similar to the apparatus in Patent Documents 2 and 3 and a winding method in accordance with the methods disclosed therein. Further explanation of the first step is omitted.

[0062] The second step is to form a series coil group 50 from the intermediate body 60. The second step is to twist the second region R2 of the connecting wire 63 (see Figure 11). In this embodiment, the direction in which the second region R2 of the connecting wire 63 is twisted is the "A" side in the outer circumference direction of the third portion of the flat wire forming the second region R2 of the connecting wire 63. The angle at which the second region R2 of the connecting wire 63 is twisted is the twist angle (θ) described above. In this embodiment, the second step rotates the second assembly 62 relative to the first assembly 61 by 150° toward the "A" side in the outer circumference direction of the third portion of the flat wire forming the second region R2 of the connecting wire 63. The central axis L shown by the dashed line on the left side of Figure 11 indicates the rotation center of the twisting process performed in the second step. The central axis L may be along the length direction of the flat wire forming the second region R2 of the connecting wire 63. The central axis L may be along the stacking direction.

[0063] In the second step, the intermediate body 60 is formed into a series coil group 50. The first assembly 61 becomes the first coil 41, which includes multiple coil layers 55. The second assembly 62 becomes the second coil 42, which also includes multiple coil layers 55. A twisted portion 44 is formed in the second region R2 of the connecting wire 63, and the connecting wire 63 becomes a jumper wire 43, which includes the twisted portion 44 and the untwisted portion 45. The lead wire 46 of the intermediate body 60 becomes the lead wire 46 of the series coil group 50, and the lead wire 47 of the intermediate body 60 becomes the lead wire 47 of the series coil group 50.

[0064] <Effects of the Embodiment> According to this embodiment, the following effects can be obtained.

[0065] (1) The motor 10 comprises a rotor 20 and a stator 30 (see Figures 1 and 2). The stator 30 includes a stator core 31 and a plurality of coils 40 (see Figures 2, 4 and 5). The stator core 31 is formed by laminating steel plates. The stator core 31 includes a yoke 32 and a plurality of teeth 35. The coils 40 are provided on the teeth 35 (see Figures 2, 4 to 8).

[0066] The stator 30 includes a first coil 41 and a second coil 42 as multiple coils 40, and a jumper wire 43 (see Figures 4-8, 10 and the right side of Figure 11). The first coil 41 is formed by spirally winding the first portion of a rectangular wire, the second coil 42 is formed by spirally winding the second portion of a rectangular wire, and the jumper wire 43 is formed by the third portion of a rectangular wire (see Figure 9 and the right side of Figure 11). The third portion of the rectangular wire is connected to the first and second portions of the rectangular wire between them (see Figure 9). The first coil 41 is provided on the first tooth 36 of the multiple teeth 35, and the second coil 42 is provided on the second tooth 37 of the multiple teeth 35 (see Figures 2, 4, 5, 7, 8). The first tooth 36 is adjacent to the second tooth 37 in the circumferential direction. The jumper wire 43 connects the first coil 41 and the second coil 42 in series (see Figures 6, 10 and the right side of Figure 11). The first coil 41, the second coil 42, and the connecting wire 43 form a series coil group 50 (see Figures 4-8, 10 and the right side of Figure 11).

[0067] The connecting wire 43 includes a twisted portion 44 and an untwisted portion 45 (see Figures 6-8 and the right side of Figure 11). The twisted portion 44 has a shape in which the third portion of the rectangular wire is twisted in the direction of the outer circumference of this third portion. The untwisted portion 45 is the portion of the connecting wire 43 excluding the twisted portion 44. The second coil 42 is wound in a spiral shape around the second portion of the rectangular wire in the same direction as the first portion of the rectangular wire in the first coil 41 (see Figures 9 and the right side of Figure 11). In the connecting wire 43, the first wire length of the twisted portion 44 is set to be less than or equal to the second wire length of the untwisted portion 45.

[0068] The stator 30 includes a leader wire 46 (see Figures 4-8, 10 and the right side of Figure 11). The leader wire 46 is formed by a fourth portion of a flat wire (see Figure 9 and the right side of Figure 11). The fourth portion of the flat wire is connected to the side opposite to the third portion of the first portion of the flat wire (see Figure 9). The leader wire 46 is provided on the first side in the stacking direction from the first end face of the stator core 31 (see Figures 4, 7, 8). The connecting wire 43 is provided on the second side in the stacking direction from the second end face of the stator core 31 (see Figures 5, 7, 8).

[0069] The motor 10 facilitates the manufacturing of the series coil group 50. After winding a continuous flat wire, the series coil group 50 can be formed by twisting the third portion of the flat wire at the position where the twisted portion 44 of the flat wire is located. The winding and connecting processes for the first coil 41 and the second coil 42 can be simplified. The size of the stator 30 can be kept down. The productivity of the series coil group 50 can be improved.

[0070] (2) The series coil group 50 includes two first coils 41 and a second coil 42, and one yoke piece 33 is provided with two first teeth 36 and a second tooth 37 (see Figures 2, 4, 5, 7, and 8). In the stator 30, the stator core 31 is divided in the following manner. In this manner, the number of coils 40 in one series coil group 50 matches the number of teeth 35 provided on one yoke piece 33. With this configuration, one series coil group 50 can be assembled for one yoke piece 33. This makes it easier to handle the following assemblies and improves the productivity of the stator 30. In this assembly, the first coil 41 is provided on the first tooth 36 via an insulating member 70, the second coil 42 is provided on the second tooth 37 via an insulating member 70, and the first tooth 36 and the second tooth 37 are provided on the yoke piece 33 (see Figure 8).

[0071] <Variation> The embodiment can also be as follows. Some of the modifications shown below can be combined and adopted as appropriate. Below, we will explain the differences from the above, and explain the similarities as appropriate.

[0072] (1) An internal rotation type motor 10 is given as an example of a rotating machine (see Figures 1 and 2). The stator 30 of the motor 10 includes a series coil group 50 (see Figures 4 to 8 and 10). In the series coil group 50, the jumper wire 43 connects the first coil 41 and the second coil 42 in series and includes a twisted portion 44 and an untwisted portion 45 (see Figures 6 to 8 and 10 and the right side of Figure 11). The first wire length of the twisted portion 44 in the longitudinal direction of the flat wire is set to be less than or equal to the second wire length of the untwisted portion 45 in the longitudinal direction. The series coil group 50 can also be used in the stator of an external rotation type motor. In addition, the series coil group 50 can also be used in the coils of the stator of a generator and the coils of a transformer.

[0073] (2) In the stator core 31, the yoke 32 is formed by assembling a plurality of yoke pieces 33 in an annular shape (see Figure 2). The yoke may be a single, annular structure. In this case, the yoke is formed by punching out an annular shape from a steel plate and then stacking the annularly punched steel plates. The integral annular yoke is provided with a plurality of mounting grooves, similar to the plurality of mounting grooves 34 of the yoke pieces 33. Teeth are mounted in the mounting grooves.

[0074] The stator core 31 has a segmented structure in which the yoke 32 and a plurality of teeth 35 are divided (see Figures 2, 4 to 8). The stator core 31 is formed by mounting the teeth 35 in the mounting grooves 34 of the yoke piece 33. The tips of the teeth 35 are formed to be wide in the circumferential direction. The tips of the teeth 35 face the outer circumferential surface of the rotor 20. In the internal rotation type motor 10, the tips of the teeth 35 form the inner end opposite to the radial outer end of the teeth 35, and the coil 40 is mounted together with the insulating member 70 from the radial outer end of the teeth 35. In the stator core, the yoke piece and teeth may be an integrated structure. Alternatively, the stator core may be an integrated structure in which the yoke and the plurality of teeth form a single unit. When the yoke piece or the yoke and teeth are an integrated structure, the integrated yoke piece or yoke and teeth are formed by punching out a steel plate into an integrated shape and laminating the steel plates punched out into an integrated shape. When the teeth are integral with the yoke piece or yoke, the tip of the teeth does not have to be wide. The teeth may have a shape with a constant width in the radial direction. In this case, the coil 40 is mounted radially from the tip of the teeth together with the insulating member 70. In an external motor, the tip of the teeth forms the radial outer end of the teeth.

[0075] (3) The series coil group 50 includes a first coil 41, a second coil 42, a jumper wire 43, and lead wires 46, 47 (see Figures 4-8, 10 and the right side of Figure 11). The series coil group may include three or more coils. Suppose the series coil group includes a third coil. In this case, the series coil group includes a second jumper wire as the second jumper wire. In this explanation, the first jumper wire corresponding to jumper wire 43 is called the "first jumper wire". The third part of the rectangular wire forms the first jumper wire, as described above. This series coil group is formed by a single continuous rectangular wire, similar to the series coil group 50. However, this rectangular wire includes the sixth and seventh parts in addition to the first to fifth parts. The sixth part of the rectangular wire forms the third coil. The seventh part of the rectangular wire is connected to the second and sixth parts between the second and sixth parts of the rectangular wire. The seventh part of the rectangular wire forms the second jumper wire. The fifth portion of the rectangular wire connects to the opposite side of the seventh portion of the sixth portion of the rectangular wire, forming a lead wire 47. In this series coil group, the lead wire 46, the first coil 41, the first jumper wire, the second coil 42, the second jumper wire, the third coil, and the lead wire 47 are integrally formed in this order by a single continuous rectangular wire. The second jumper wire connects the second coil 42 and the third coil in series. In other words, the first coil 41, the second coil 42, and the third coil are connected in series by two first and second jumper wires. It is preferable that the number of teeth provided on one yoke piece be the same as the number of coils in the series coil group.

[0076] (4) The same "stack direction" as for the motor 10 was used to identify the series coil group 50 and the intermediate body 60. The series coil group 50 and the intermediate body 60 may also be identified by the following "first direction", "second direction", "first axis direction", and "second axis direction". The first direction corresponds to the direction in which the flat wires overlap in the coil layer 55, the coil layer of the first assembly 61, and the coil layer of the second assembly 62. The second direction is perpendicular to the first direction. The second direction may coincide with the radial direction in the state of the motor 10 (rotating machine). The state of the motor 10 (rotating machine) includes the state of the stator 30. Furthermore, the state of the motor 10 (rotating machine) and the state of the stator 30 include the state in which the coil 40 is installed on the teeth 35. The second axis direction is perpendicular to the first axis direction. With the motor 10 as the reference, the first axis direction coincides with the stack direction, and the second axis direction is perpendicular to both the stack direction and the radial direction. [Explanation of Symbols]

[0077] 10 motors, 20 rotors, 21 rotor cores, 22 shafts 30 Stator, 31 Stator core, 32 Yoke 33 Yoke piece, 34 Mounting groove, 35 Teeth 36 First tooth, 37 Second tooth, 38 Slot 40, 40U, 40V, 40W coil, 41 First coil 42 Second coil, 43, 43U, 43V, 43W jumper wires 44 Twisted section, 45 Non-twisted section 46,46U,46V,46W leader line 47,47U,47V,47W Leader line 50, 50U, 50V, 50W series coil group 51, 51U, 51V, 51W coil unit, 55 coil layers 60 intermediate, 61 first aggregate, 62 second aggregate 63 Connecting wire, 70 Insulating member, L Central axis, R2 Second region

Claims

1. Rotor and, Equipped with a stator, The stator is, A stator core formed by laminating steel plates, including a yoke and a plurality of teeth protruding from the yoke toward the rotor side, A first coil is formed by winding the first portion of a rectangular wire in a spiral shape and is provided on the first tooth of the plurality of teeth, A second coil is formed by winding the second portion of the aforementioned rectangular wire in a spiral shape and is provided on the second tooth of the plurality of teeth, A jumper wire is formed between the first and second parts by a third portion of the rectangular wire connected to the first and second parts, and connects the first coil and the second coil in series. The first teeth are adjacent to the second teeth in the circumferential direction with respect to the rotation axis of the rotor, The aforementioned crossover is, The third portion forming the connecting wire is twisted in the direction of the outer circumference of the third portion, Including the non-twisted portion excluding the aforementioned twisted portion, The second coil is wound in a spiral shape around the second portion in the same direction as the first portion. The aforementioned jumper wire connects the first coil and the second coil in series such that the flow of electricity in the second coil is in the opposite direction to the flow of electricity in the first coil. The twisted portion is provided in the region of the connecting wire along the lamination direction in which the steel plates are stacked, in the state of the stator in which the first coil is provided on the first teeth and the second coil is provided on the second teeth. A rotating machine wherein the length of the first wire of the twisted portion in the longitudinal direction of the rectangular wire is set to be less than or equal to the length of the second wire of the untwisted portion in the longitudinal direction.

2. The stator is formed by a fourth portion of the rectangular wire connected to the side of the third portion of the part, and includes a leader wire provided on the first side in the stacking direction from the first end face on the first side in the stacking direction of the stator core, The rotating machine according to claim 1, wherein the connecting wire is provided on the second side in the stacking direction from the second end face on the second side opposite to the first side in the stacking direction of the stator core.

3. The yoke is It includes multiple yoke pieces, and The plurality of yoke pieces are assembled in a ring shape to form the above, The rotating machine according to claim 1 or claim 2, wherein the first teeth and the second teeth protrude toward the rotor from the first yoke piece among the plurality of yoke pieces.

4. A first coil is formed by winding the first portion of a flat wire in a spiral shape, and is provided on the first tooth of the plurality of teeth adjacent to the second tooth of the plurality of teeth provided on the stator core of the stator of the rotating machine in the circumferential direction with respect to the rotation axis of the rotor of the rotating machine, The second coil is formed by winding the second portion of the aforementioned rectangular wire in a spiral shape and is provided on the second teeth, A jumper wire is formed between the first and second parts by a third portion of the rectangular wire connected to the first and second parts, and connects the first coil and the second coil in series. The aforementioned crossover is, The third portion forming the connecting wire is twisted in the direction of the outer circumference of the third portion, Including the non-twisted portion excluding the aforementioned twisted portion, The second coil is wound in a spiral shape around the second portion in the same direction as the first portion. The aforementioned jumper wire connects the first coil and the second coil in series such that the flow of electricity in the second coil is in the opposite direction to the flow of electricity in the first coil. The twisted portion is provided in the region of the connecting wire along the lamination direction in which the steel plates forming the stator core are laminated, in the state of the stator in which the first coil is provided on the first teeth and the second coil is provided on the second teeth. A series of coils wherein the length of the first wire in the twisted portion in the longitudinal direction of the rectangular wire is set to be less than or equal to the length of the second wire in the non-twisted portion in the longitudinal direction.

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