Stator for rotating electric machines

Abstract

The goal is to reduce the axial size of the coil end on the non-welded side. [Solution] A stator for a rotating electric machine is disclosed, wherein the stator coils are arranged in parallel in a number of 2 or more, the crossover section includes a first crossover section of a first pitch and a second crossover section of a second pitch within the circumferential range of the first crossover section, the first pitch is greater than the second pitch, the pair of slot housings of the first pitch are arranged at the innermost radial position and the outermost radial position, the pair of slot housings of the second pitch are arranged at the innermost radial position and the outermost radial position, the first crossover section has a first top located at the outermost axial position, the second crossover section has a second top located at the outermost axial position, the base of the first crossover section and the base of the second crossover section are radially offset from each other, and the first top and the second top do not overlap in the axial direction.

Description

Technical Field

[0001] The present disclosure relates to a stator for a rotating electrical machine.

Background Art

[0002] A technique is known in which, among the coil ends on both axial sides, the connecting portion continuous from the pair of slot accommodating portions of 7 slot pitches and the connecting portion continuous from the pair of slot accommodating portions of 5 slot pitches at the non-welded side coil end are arranged axially overlapping each other.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in such a conventional technique, the apexes (the portions located most axially outward) in the two types of connecting portions are likely to overlap axially. When the apexes overlap axially, the axial physical size of the coil end increases.

[0005] Therefore, on one side, an object of the present disclosure is to reduce the axial physical size related to the non-welded side coil end.

Means for Solving the Problems

[0006] On one side, a stator coil to which three-phase alternating current power is supplied, and a stator core having a plurality of slots around which the stator coil is wound are provided. The plurality of slots include a first slot and a second slot that are adjacent in the circumferential direction, and a third slot and a fourth slot that are different from the first slot and the second slot and are adjacent in the circumferential direction. The first slot and the fourth slot are spaced apart in the circumferential direction by the first slot pitch. The second slot and the third slot are spaced apart in the circumferential direction with a second slot pitch smaller than the first slot pitch. The stator coil, in the same phase of the three phases, A first slot housing portion is located at the outermost radial position of the first slot, A first root portion that is continuous with the first slot housing portion and extends axially from the end face of the stator core, A second slot housing portion is located at the outermost radial position of the second slot, A second root portion that is continuous with the second slot housing portion and extends axially from the end face of the stator core, A third slot housing portion is located at the innermost radial position of the third slot, A third root portion that is continuous with the third slot housing portion and extends axially from the end face of the stator core, A fourth slot housing portion is located at the innermost radial position of the fourth slot, A fourth root portion that is continuous with the fourth slot housing portion and extends axially from the end face of the stator core, A first circumferential portion that extends in the circumferential direction and includes a first crown portion located on the outermost side in the axial direction, and integrally connects the first root portion and the fourth root portion via the first crown portion, A second circumferential portion extending in the circumferential direction and including a second crown portion located on the outermost side in the axial direction, integrally connecting the second root portion and the third root portion via the second crown portion, Includes, The first root portion and the second root portion are offset radially outward from the other, or The fourth root portion and the third root portion are offset radially inward from the other, A stator for a rotating electric machine is provided in which the first top portion and the second top portion do not overlap in the axial direction. [Effects of the Invention]

[0007] In one respect, this disclosure makes it possible to reduce the axial size of the coil end on the non-welded side. [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view of the rotating electric machine (stator) according to this embodiment. [Figure 2] This is a circuit diagram of a Y-connected three-phase coil according to this embodiment. [Figure 3] This is a perspective view of the stator according to this embodiment. [Figure 4] This is a diagram illustrating the configuration of the coil pieces that form the stator coil. [Figure 4A] This is a diagram illustrating the structure (wave winding) of the coil pieces that form the stator coil. [Figure 5] This figure shows the configuration of the U1 coil section of the U-phase coil according to Example 1 (part 1). [Figure 6] This figure shows the configuration of the U1 coil section of the U-phase coil according to Example 1 (part 2). [Figure 7] This figure shows the configuration of the U2 coil section of the U-phase coil according to Example 1 (part 1). [Figure 8] This figure shows the configuration of the U2 coil section of the U-phase coil according to Example 1 (part 2). [Figure 9] This figure shows the configuration of the U3 coil section of the U-phase coil according to Example 1 (part 1). [Figure 10] This figure shows the configuration of the U3 coil section of the U-phase coil according to Example 1 (part 2). [Figure 11] This figure shows the configuration of the U4 coil section of the U-phase coil according to Example 1 (part 1). [Figure 12] This figure shows the configuration of the U4 coil section of the U-phase coil according to Example 1 (part 2). [Figure 13] It is an explanatory diagram of the circulating current. [Figure 14] It is a perspective view showing only all the coil pieces forming the U-phase coil. [Figure 15] It is a perspective view showing only the U1 coil part and the U2 coil part of the U-phase coil. [Figure 16] It is a perspective view of a coil piece provided with a standard pitch bridging part. [Figure 17] It is a perspective view of a coil piece provided with a long pitch bridging part. [Figure 18] It is a perspective view of a coil piece provided with a short pitch bridging part. [Figure 19] It is an enlarged view of the Q18 part in FIG. 15. [Figure 20] It is a perspective view explaining the relationship between the long pitch bridging part and the short pitch bridging part with respect to the U1 coil part and the U2 coil part. [Figure 21] It is a perspective view explaining the relationship between the standard pitch bridging part of the U3 coil part and the U4 coil part and the long pitch bridging part and the short pitch bridging part of the U1 coil part and the U2 coil part. [Figure 22] It is a diagram showing the configuration (part 1) of the U1 coil part of the U-phase coil according to Example 2. [Figure 23] It is a diagram showing the configuration (part 2) of the U1 coil part of the U-phase coil according to Example 2. [Figure 24] It is a diagram showing the configuration (part 1) of the U2 coil part of the U-phase coil according to Example 2. [Figure 25] It is a diagram showing the configuration (part 2) of the U2 coil part of the U-phase coil according to Example 2. [Figure 26] It is a diagram showing the configuration (part 1) of the U3 coil part of the U-phase coil according to Example 2. [Figure 27] It is a diagram showing the configuration (part 2) of the U3 coil part of the U-phase coil according to Example 2. [Figure 28] It is a diagram showing the configuration (part 1) of the U4 coil part of the U-phase coil according to Example 2. [Figure 29]This figure shows the configuration of the U4 coil section of the U-phase coil according to Example 2 (part 2). [Figure 30] This is a perspective view of the stator according to Example 3. [Figure 31] This is an enlarged view of the stator coil according to Example 3, seen from the radially inner side. [Figure 32] This is a perspective view showing all the coil pieces that form the U-phase coil of the stator coil according to Example 3. [Figure 33] This is a perspective view of a coil piece with a long-pitch connecting section. [Figure 34] This is a perspective view of a coil piece with a short-pitch connecting section. [Figure 35] This is a perspective view illustrating the relationship between the long-pitch connecting section and the short-pitch connecting section for the U1 coil section and the U2 coil section. [Figure 36] This is a perspective view illustrating the relationship between the standard pitch connecting sections of the U3 and U4 coil sections and the long-pitch and short-pitch connecting sections of the U1 and U2 coil sections. [Figure 37] This is a plan view of a portion of the stator as seen from the Z1 side, illustrating the relationship between the neutral busbar and the short-pitch top section. [Figure 38] Figure 37 is a plan view showing the state with the neutral busbar removed. [Figure 39] This is a plan view of another part of the stator as seen from the Z1 side, showing the relationship between the power line busbars and the short-pitch top section. [Modes for carrying out the invention]

[0009] The following describes each embodiment in detail with reference to the attached drawings. Note that the dimensional ratios in the drawings are merely examples and are not exhaustive. Furthermore, shapes and other details in the drawings may be partially exaggerated for illustrative purposes. Also, for clarity, in some cases, only a portion of parts with the same attribute are assigned reference numerals in the drawings.

[0010] Figure 1 is a plan view of the rotating electric machine 200 (stator 100) according to this embodiment.

[0011] In this specification, "axial direction" means the direction along the rotation axis (symbol O) of the stator core 10 (rotor 150) (Z direction: see Figure 1). The respective sides in the axial direction are designated as the Z1 side and the Z2 side. "Circumferential direction" means the circumferential direction (A direction) of the stator core 10. The respective directions in the circumferential direction are designated as the A1 direction and the A2 direction. "Radial direction" means the radial direction (B direction) with respect to the rotation axis O of the stator core 10 (rotor 150). "Inner radial direction" and "inner diameter side" mean the direction toward the center of the stator core 10 (B1 direction). "Outer radial direction" and "outer diameter side" mean the direction toward the outside of the stator core 10 (B2 direction).

[0012] As shown in Figure 1, the rotating electric machine 200 comprises a stator 100 and a rotor 150. Each of the stator 100 and rotor 150 is formed in an annular shape. The stator 100 and rotor 150 face each other. The rotor 150 is positioned radially inward (towards the B1 direction) of the stator 100. The rotor 150 is provided with a plurality of permanent magnets (not shown). In other words, the rotating electric machine 200 of this embodiment is configured as an inner rotor type rotating electric machine.

[0013] The stator 100 includes a stator core 10. The stator core 10 is positioned radially opposite the rotor 150. The stator core 10 is also provided with a plurality of (for example, 48) slots 11. Teeth 12 are provided between adjacent slots 11. The stator core 10 is configured such that, for example, a plurality of electromagnetic steel sheets are stacked in the rotational axis direction (Z direction) and magnetic flux can pass through it. The stator core 10 may also be formed by compression molding of magnetic powder. The stator core 10 has end faces 10a on one side (Z1 side) and the other side (Z2 side) in the axial direction. The stator 100 also includes a stator coil 20.

[0014] Figure 2 is a circuit diagram of a Y-connected three-phase coil according to this embodiment.

[0015] As shown in Figure 2, the stator coil 20 is connected to an external power supply and is configured to receive power (for example, three-phase AC power). The stator coil 20 is configured to generate a magnetic field when power is supplied. The stator coil 20 includes a U-phase coil 30, a V-phase coil 40, and a W-phase coil 50, through which the three-phase (U-phase, V-phase, and W-phase) AC currents flow, respectively.

[0016] The U-phase coil 30 includes U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34, which are connected in parallel to each other. The V-phase coil 40 also includes V1 coil section 41, V2 coil section 42, V3 coil section 43, and V4 coil section 44, which are connected in parallel to each other. The W-phase coil 50 also includes W1 coil section 51, W2 coil section 52, W3 coil section 53, and W4 coil section 54, which are connected in parallel to each other. The U-phase coil 30, V-phase coil 40, and W-phase coil 50 are connected in a Y-connection (star connection). In other words, a so-called "4Y" connection is realized. The AC power related to the U-phase, V-phase, and W-phase, respectively, is input from the power line terminal 61 to the U-phase coil 30, V-phase coil 40, and W-phase coil 50, respectively. The output sides of the U-phase coil 30, V-phase coil 40, and W-phase coil 50 are connected to each other via the neutral wire terminal 62.

[0017] In the example shown in Figure 2, the "4Y" connection is achieved by combining two so-called "2Y" connections, but the "4Y" connection can also be achieved directly. That is, the neutral wire ends from coil section U1 31 to coil section U4 34 may be connected to one terminal, the neutral wire ends from coil section V1 41 to coil section V4 44 may be connected to one terminal, and the neutral wire ends from coil section W1 51 to coil section W4 54 may be connected to one terminal, and these three terminals may then be connected to each other.

[0018] Figure 3 is a perspective view of the stator 100 according to this embodiment. Figure 4 is a diagram illustrating the configuration of the coil pieces 70 that form the stator coil 20. Figure 4A is a diagram illustrating the configuration (wave winding) of the coil pieces 70 that form the stator coil 20.

[0019] As shown in Figure 3, the stator coil 20 is wound around the stator core 10. In this embodiment, the stator coil 20 consists of multiple coil pieces 70 (Figure 4) arranged in each of the multiple slots 11. Figure 4 shows the relationship between two coil pieces 70 as an example, but the other coil pieces 70 will be described later with reference to Figures 14 to 16, etc. Each of the multiple coil pieces 70 may have an inverted U shape when viewed with the Z1 side as the upper side. Also, each of the multiple coil pieces 70 may be a rectangular cross-section flat conductor covered with an insulating coating. In this embodiment, overlapping winding is described as an example, but it is not limited to this. For example, in the example shown in Figure 4A, it is an example of wave winding, and the stator coil 20 is formed as a wave-wound conductor by connecting multiple coil pieces 70.

[0020] Each of the multiple coil pieces 70 may have an inverted U-shape with the Z2 side open or an O-shape with the Z2 side closed. Each of the multiple coil pieces 70 may be formed by molding the Z1 side with a mold and by bending the Z2 side after assembly. Note that Figure 4 is an explanatory diagram and only shows a portion of the multiple coil pieces 70, but the bending method will differ depending on the type of coil piece 70 (described later).

[0021] Although there are multiple types of coil pieces 70, we will first describe their common characteristics.

[0022] Each of the multiple coil pieces 70 includes a slot housing portion 21 and a connecting portion 22.

[0023] The slot housing section 21 extends in the axial direction (Z direction) and is housed in each of the multiple slots 11.

[0024] The connecting section 22 connects multiple slot housing sections 21 in pairs. In other words, the connecting section 22 connects slot housing sections 21 that are housed in different slots 11. The connecting section 22 is formed on both the Z2 side and the Z1 side. Further details of the connecting section 22 will be described later.

[0025] As shown in Figure 4, after the slot housing portion 21 is arranged to house each of the slots 11, the ends of the Z2-side legs 71 of different coil pieces 70 may be joined together by laser bonding or the like to form the Z2-side connecting portion 22. In Figure 4, a coil piece 70 in which the Z2-side legs 71 are bent outward or inward in the circumferential direction is shown as an example, but the bending manner of the legs 71 will differ depending on the type and winding method of the coil piece 70, and various coil pieces 70 will be described later with reference to Figures 14 to 16, etc.

[0026] In this embodiment, the connecting portion 22 on the Z2 side is formed by joining the leg portions 71 of the two coil pieces 70 together. On the other hand, the connecting portion 22 on the Z1 side is a continuous form without a joint and may be formed by a mold.

[0027] In the stator coil 20, the U-phase coil 30, V-phase coil 40, and W-phase coil 50 have substantially the same configuration. Therefore, the following description will mainly focus on the U-phase coil 30.

[0028] The U-phase coil 30 is arranged on the stator core 10 in a manner in which four sets of U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 form a parallel circuit. One end of each of the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 is connected to the power line terminal 61. AC power is supplied from the power line terminal 61. The other end of each of the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 is connected to the neutral wire terminal 62.

[0029] Figures 5 and 6 show the configuration of the U1 coil section 31 of the U-phase coil 30. Figures 7 and 8 show the configuration of the U2 coil section 32 of the U-phase coil 30. Figures 9 and 10 show the configuration of the U3 coil section 33 of the U-phase coil 30. Figures 11 and 12 show the configuration of the U4 coil section 34 of the U-phase coil 30. Figure 13 is an explanatory diagram of circulating current. In Figure 13, the flow of circulating current between the U1 coil section 31 and the U2 coil section 32 is schematically shown by arrows.

[0030] In Figures 5 to 12, the number below the word "Turn" on the left indicates the turn position (which turn it is), and the number below the word "#" indicates the slot position. For example, out of 48 slots 11, the position of the first slot is indicated by "#1". The slot housing section 21 is indicated by a white circle mark at the corresponding turn position in each corresponding slot 11. Within the white circles, there are white circles and cross marks, and these two types of marks represent the direction of current flow.

[0031] In Figures 5 to 12, the connecting section 22 on the Z1 side is shown with a solid line, and the connecting section 22 on the Z2 side is shown with a dotted line.

[0032] In this embodiment, the U-phase coil 30 has a 6-turn configuration and is wound around the stator core 10 in an overlapping winding manner. In this embodiment, the number of turns is "6", but the number of turns may be any number other than 6 (for example, an even number).

[0033] Specifically, as shown in the hatched areas in Figures 5 to 12, the U-phase coil 30 is placed in slots #5, #6, #11, #12, #17, #18, #23, #24, #29, #30, #35, #36, #41, #42, #47, and #48 of the 48 slots 11. Here, slots 11 of #5 and #6, slots 11 of #11 and #12, slots 11 of #17 and #18, slots 11 of #23 and #24, slots 11 of #29 and #30, slots 11 of #35 and #36, slots 11 of #41 and #42, and slots 11 of #47 and #48 are each two adjacent slots 11 in the circumferential direction (direction A) (for example, the circumferentially outer side of the circumferential center of the connecting portion 22 is an example of the first or fourth slot, and the circumferentially inner side of the center of the connecting portion 22 is an example of the second or third slot). Figures 5 to 12 show the annular stator core 10 in an unfolded state, with the vertical direction being the radial direction (direction B) of the stator core 10 and the horizontal direction being the circumferential direction (direction A) of the stator core 10. In other words, in Figures 5 and 6, the right end of Figure 5 and the left end of Figure 6 are connected to each other, and the left end of Figure 5 and the right end of Figure 6 are connected to each other. The same applies to Figures 7 and 8, Figures 9 and 10, and Figures 11 and 12. Although not shown in the illustration, the V-phase coil 40 and the W-phase coil 50 are positioned in the stator core 10 with an offset of 2 and 4 slots 11 from the U-phase coil 30, respectively. Here, using the lead-out positions of the power line terminal 61 and the neutral line terminal 62 as a reference, the V-phase and W-phase are positioned with a shift of 4 and 8 slots relative to the U-phase. Along the A1 direction, the U-phase, W-phase, and V-phase are positioned with a circumferential shift of 4 and 8 slots, respectively.

[0034] The multiple slot housings 21 are housed in each of the multiple slots 11, arranged along the radial direction (B direction) of the stator core 10. Specifically, in this embodiment, six slot housings 21 are arranged in a single row radially within one slot 11. For example, in one slot 11, the slot housing 21 located on the outermost side (outer diameter side: B2 direction side) is designated as the 1st turn (1st layer), and the slot housing 21 located on the innermost side (inner diameter side: B1 side) is designated as the 6th turn (6th layer).

[0035] In this embodiment, as described above, the slot housing section 21 is inserted into two adjacent slots 11 in the circumferential direction (direction A). The two slots 11 are arranged periodically along the circumferential direction with a 6-slot pitch (with a gap of 4 slots between them). Hereinafter, of the two adjacent slots 11 in the circumferential direction (direction A), the slot 11 closer to slot #1 will be referred to as the "odd-numbered slot 11" in ascending order, and the slot 11 further from slot #1 will be referred to as the "even-numbered slot 11".

[0036] In this embodiment, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 do not have a configuration in which multiple slot housing sections 21 are inserted concentrated in only one of the odd-numbered slots 11 and the even-numbered slots 11. Rather, they have a configuration in which multiple slot housing sections 21 are inserted distributed between the odd-numbered slots 11 and the even-numbered slots 11.

[0037] Specifically, the U1 coil section 31 has slot housing sections 21 inserted into each of the slots 11 of #5, #11, #18, #24, #29, #35, #42, and #48. That is, it is evenly distributed between the four odd-numbered slots 11 and the four even-numbered slots 11. The U1 coil section 31 is wound starting from the neutral wire terminal 62 in the A2 direction and is wound in a clockwise direction when viewed in the B2 direction (in a manner in which the current flow from the neutral wire terminal 62 is clockwise in each coil element, the same applies hereinafter).

[0038] The U2 coil section 32 has slot housings 21 inserted into each of the slots 11 of #5, #12, #18, #23, #29, #36, #42, and #47. That is, it is evenly distributed between the four odd-numbered slots 11 and the four even-numbered slots 11. The U2 coil section 32 is wound starting from the neutral wire terminal 62 in the A1 direction and is wound in a counterclockwise direction when viewed in the B2 direction.

[0039] The U3 coil section 33 has slot housings 21 inserted into each of the slots 11 of #6, #12, #17, #23, #30, #36, #41, and #47. That is, it is evenly distributed between the four odd-numbered slots 11 and the four even-numbered slots 11. The U3 coil section 33 is wound starting from the neutral wire terminal 62 in the A2 direction and is wound in a clockwise direction when viewed in the B2 direction.

[0040] The U4 coil section 34 has slot housings 21 inserted into each of the slots 11, #6, #11, #17, #24, #30, #35, #41, and #48. That is, it is evenly distributed between the four odd-numbered slots 11 and the four even-numbered slots 11. The U4 coil section 34 is wound starting from the neutral wire terminal 62 in the A1 direction and is wound in a counterclockwise direction when viewed in the B2 direction.

[0041] In this embodiment, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 each have multiple slot housing sections 21 inserted, distributed between the odd-numbered slots 11 and the even-numbered slots 11. Specifically, there are two types of 3-turn unit coils. For the first unit coil, the slot housing section 21 is inserted into the odd-numbered slot 11 on the side closer to the neutral wire, and for the second unit coil, the slot housing section 21 is inserted into the even-numbered slot 11 on the side closer to the neutral wire. The first and second unit coils are then arranged alternately in the circumferential direction. This helps to reduce circulating current. In other words, in a comparative example where, for example, the slot housing 21 is inserted only into the odd-numbered slots 11 in the U1 coil section 31, and the slot housing 21 is inserted only into the even-numbered slots 11 in the U2 coil section 32, the difference in back electromotive force that can occur between the U1 coil section 31 and the U2 coil section 32 becomes large, and the circulating current (see Figure 13) tends to increase. In contrast, according to this embodiment, the circulating current can be reduced by minimizing this difference in back electromotive force.

[0042] Furthermore, in this embodiment, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 do not have a configuration in which multiple slot accommodating sections 21 are inserted only at the 1st to 3rd turn positions or only at the 4th to 6th turn positions out of 6 turns, respectively. Rather, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 each have a configuration in which multiple slot accommodating sections 21 are inserted distributed among the 1st to 6th turn positions.

[0043] Specifically, in the U1 coil section 31, slot housings 21 are inserted in slots 11 of the following slots: #5, #11, #18, #24, #29, #35, #42, and #48, specifically in slots #5, #18, #29, and #42, at radial positions corresponding to the 1st, 3rd, and 5th turns. In addition, in the remaining slots 11 of the following slots: #11, #24, #35, and #48, slot housings 21 are inserted at radial positions corresponding to the 2nd, 4th, and 6th turns.

[0044] In the U2 coil section 32, slot housings 21 are inserted in slots 11 of #5, #12, #18, #23, #29, #36, #42, and #47, specifically in slots #12, #23, #36, and #47, at radial positions corresponding to the 1st, 3rd, and 5th turns. In the remaining slots 11 of #5, #18, #29, and #42, slot housings 21 are inserted at radial positions corresponding to the 2nd, 4th, and 6th turns.

[0045] The same applies to the U3 coil section 33 and the U4 coil section 34.

[0046] In this way, according to this embodiment, the circulating current can be reduced by inserting multiple slot accommodating sections 21 at positions 1 to 6 in each of the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34. That is, in a comparative example, for example, in the U1 coil section 31, slot accommodating sections 21 are inserted only at positions 1 to 3, and in the U2 coil section 32, slot accommodating sections 21 are inserted only at positions 4 to 6, the loss due to eddy currents in the U2 coil section 32 is significantly larger than the loss in the U1 coil section 31. Due to this difference, the difference in back electromotive force that can occur between the U1 coil section 31 and the U2 coil section 32 becomes large, and the circulating current tends to increase. In contrast, according to this embodiment, the circulating current can be reduced by minimizing this difference in back electromotive force.

[0047] Furthermore, in this embodiment, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 do not have a configuration in which six turns of slot housing section 21 are concentrated and inserted into the corresponding slot 11. Rather, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 each have a configuration in which three turns of slot housing section 21 are inserted into the corresponding slot 11. As a result, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 each have multiple slot housing sections 21 arranged substantially evenly around their entire 360-degree circumference.

[0048] In this embodiment, the U1 coil section 31, U2 coil section 32, U3 coil section 33, and U4 coil section 34 each have a plurality of slot housing sections 21 arranged substantially evenly around the entire 360-degree circumference, thereby reducing circulating current. That is, for example, in a comparative example where, in the U1 coil section 31, slot housing sections 21 for 6 turns are inserted into the corresponding slot 11, and in the U2 coil section 32, slot housing sections 21 for 6 turns are also inserted into the corresponding slot 11, the U1 coil section 31 and the U2 coil section 32 will each only be arranged within a circumferential range of 180 degrees. In a comparative example with such a bias, the difference in back electromotive force that can occur between the U1 coil section 31 and the U2 coil section 32 due to eccentricity of the rotor 150, etc., tends to be large, and the circulating current tends to be large. In contrast, according to this embodiment, the circulating current can be reduced by minimizing such a difference in back electromotive force.

[0049] In the following, a characteristic configuration that contributes to minimizing such differences in back electromotive force (a configuration that enhances the uniformity of the parallel coil arrangement in the circumferential, radial, and axial directions) will also be referred to as a "highly uniform parallel coil arrangement."

[0050] In this embodiment, the power lines of the U1 coil section 31 and the U3 coil section 33 are adjacent in the circumferential direction on the first turn (first layer), and the power lines of the U2 coil section 32 and the U4 coil section 34 are adjacent in the circumferential direction on the sixth turn (sixth layer). The neutral wire of the U1 coil section 31 and the neutral wire of the U3 coil section 33 are adjacent in the circumferential direction on the sixth turn from a slot different from the slot where the power lines are arranged. The neutral wire of the U2 coil section 32 and the neutral wire of the U4 coil section 34 are adjacent in the circumferential direction on the first turn from a slot different from the slot where the power lines are arranged.

[0051] In this embodiment, the connecting portion 22 on the Z2 side is joined at an intermediate position in the circumferential direction. In Figures 5 to 12, each joint 90 related to the connecting portion 22 on the Z2 side is schematically shown by black dots (reference numeral 90 is assigned to only some of them). For example, the connecting portion 22 on the Z2 side between slot 11 #42 and slot 11 #48 has a joint 90 at a circumferential position corresponding to slot 11 #45. Also, the connecting portion 22 on the Z2 side between slot 11 #29 and slot 11 #35 has a joint 90 at a circumferential position corresponding to slot 11 #32.

[0052] In this embodiment, the connecting portion 22 on the Z1 side has four different forms. Specifically, the connecting portion 22 on the Z1 side consists of four types: connecting portion 221, connecting portion 222, connecting portion 223, and connecting portion 224 (see also Figure 15). This makes it possible to minimize the number of molds required to form the connecting portion 22 on the Z1 side.

[0053] The connecting sections 221 and 222 are formed continuously from a pair of slot housing sections 21 that are inserted into the slots 11 at a 6-slot pitch (an example of a standard slot pitch). The number "6" in the 6-slot pitch corresponds to the number of slots / number of poles (48 / 8 in this example), and hereafter, the 6-slot pitch will also be referred to as the "standard slot pitch". Note that the connecting sections 221 and 222 only differ in their radial position and extend within the same circumferential range. For example, in the U1 coil section 31, the connecting sections 221 and 222 extend between slot #5 and slot #11, between slot #18 and slot #24, between slot #29 and slot #35, and between slot #42 and slot #48, respectively.

[0054] Hereinafter, the connecting section 221 and the connecting section 222 will also be referred to as "standard pitch connecting section 221" and "standard pitch connecting section 222," respectively.

[0055] The connecting sections 223 and 224 have a characteristic configuration that contributes to the highly uniform parallel coil arrangement described above.

[0056] Specifically, the connecting section 223 is formed continuously from a pair of slot-receiving sections 21 that are inserted into the slot 11 with a 7-slot pitch (an example of a first slot pitch) which is one slot larger than the standard slot pitch. Hereafter, the connecting section 223 will also be referred to as the "long-pitch connecting section 223".

[0057] The pair of slot housing sections 21, which are continuous with the long-pitch connecting section 223, are positioned at the innermost radial position (i.e., the 6th turn) and the outermost radial position (i.e., the 1st turn), respectively.

[0058] Specifically, in the U1 coil section 31, the long-pitch connecting section 223 is formed continuously from the slot housing section 21 in slot #11 and the slot housing section 21 in slot #18. In this case, the slot housing section 21 in slot #11 that is continuous with the long-pitch connecting section 223 is located in the 6th turn. The slot housing section 21 in slot #18 that is continuous with the long-pitch connecting section 223 is located in the 1st turn.

[0059] In the U1 coil section 31, the slot housing 21 of the 6th turn in slot 11 of #35 is connected to the neutral wire terminal 62, and the slot housing 21 of the 1st turn in slot 11 of #42 is connected to the power line terminal 61. Therefore, in the U1 coil section 31, there is only one long-pitch connecting section 223.

[0060] In the U2 coil section 32, there are two long-pitch connecting sections 223. The first long-pitch connecting section 223 is formed continuously from the slot housing section 21 of the 6th turn in slot 11 of #5 and the slot housing section 21 of the 1st turn in slot 11 of #12. The second long-pitch connecting section 223 is formed continuously from the slot housing section 21 of the 6th turn in slot 11 of #29 and the slot housing section 21 of the 1st turn in slot 11 of #36.

[0061] In the U3 coil section 33, there are two long-pitch connecting sections 223. The first long-pitch connecting section 223 is formed continuously from the slot housing section 21 of the 6th turn in the #47 slot 11 and the slot housing section 21 of the 1st turn in the #6 slot 11. The second long-pitch connecting section 223 is formed continuously from the slot housing section 21 of the 6th turn in the #23 slot 11 and the slot housing section 21 of the 1st turn in the #30 slot 11.

[0062] In the U4 coil section 34, the long-pitch connecting section 223 is formed continuously from the slot housing section 21 of the 6th turn in the #17 slot 11 and the slot housing section 21 of the 1st turn in the #24 slot 11.

[0063] In the U4 coil section 34, the slot housing 21 of the 6th turn in slot 11 of #41 is connected to the power line terminal 61, and the slot housing 21 of the 1st turn in slot 11 of #48 is connected to the neutral wire terminal 62. Therefore, in the U4 coil section 34, there is only one long-pitch connecting section 223.

[0064] The connecting section 224 is formed continuously from a pair of slot housing sections 21 that are inserted into the slot 11 with a 5-slot pitch (an example of a second slot pitch) which is one slot smaller than the standard slot pitch. Hereinafter, the connecting section 224 will also be referred to as the "short-pitch connecting section 224".

[0065] The pair of slot housing sections 21, which are continuous with the short-pitch connecting section 224, are positioned at the innermost radial position (i.e., the 6th turn) and the outermost radial position (i.e., the 1st turn), respectively.

[0066] Specifically, in the U1 coil section 31, there are two short-pitch connecting sections 224. The first short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #24 slot 11 and the slot housing section 21 of the 1st turn in the #29 slot 11. The second short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #48 slot 11 and the slot housing section 21 of the 1st turn in the #5 slot 11.

[0067] In the U2 coil section 32, the short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #18 slot 11 and the slot housing section 21 of the 1st turn in the #23 slot 11.

[0068] In the U2 coil section 32, the slot housing 21 of the 6th turn in slot 11 of #42 is connected to the power line terminal 61, and the slot housing 21 of the 1st turn in slot 11 of #47 is connected to the neutral wire terminal 62. Therefore, in the U2 coil section 32, there is only one short-pitch connecting section 224.

[0069] In the U3 coil section 33, the short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #12 slot 11 and the slot housing section 21 of the 1st turn in the #17 slot 11.

[0070] In the U3 coil section 33, the slot housing 21 of the 6th turn in slot 11 of #36 is connected to the neutral wire terminal 62, and the slot housing 21 of the 1st turn in slot 11 of #41 is connected to the power line terminal 61. Therefore, in the U3 coil section 33, there is only one short-pitch connecting section 224.

[0071] In the U4 coil section 34, there are two short-pitch connecting sections 224. The first short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #6 slot 11 and the slot housing section 21 of the 1st turn in the #11 slot 11. The second short-pitch connecting section 224 is formed continuously from the slot housing section 21 of the 6th turn in the #30 slot 11 and the slot housing section 21 of the 1st turn in the #35 slot 11.

[0072] In this embodiment, as described above, the U1 coil section 31 and the U3 coil section 33 are connected to the power line terminal 61 by the outermost radial lead wires, while the U2 coil section 32 and the U4 coil section 34 are connected to the power line terminal 61 by the innermost radial lead wires. Therefore, when current flows from the power line to the neutral line, the radial direction of current flow in the U1 coil section 31 and the U3 coil section 33 is opposite to that of the U2 coil section 32 and the U4 coil section 34.

[0073] In this embodiment, the power line terminal 61 and the neutral line terminal 62 may be arranged in reverse. That is, the U1 coil section 31 and the U3 coil section 33 may be connected to the power line terminal 61 by lead wires from the innermost radial direction, and the U2 coil section 32 and the U4 coil section 34 may be connected to the power line terminal 61 by lead wires from the outermost radial direction.

[0074] Next, the stator coil 20 will be further explained with reference to Figure 14 and subsequent figures.

[0075] Figure 14 is a perspective view showing only all the coil pieces 70 that form the U-phase coil 30, and Figure 15 is a perspective view showing only the U1 coil section 31 and U2 coil section 32 of the U-phase coil 30. Figure 16 is a perspective view of a coil piece 70 having a standard pitch connecting section 221, Figure 17 is a perspective view of a coil piece 70 having a long pitch connecting section 223, and Figure 18 is a perspective view of a coil piece 70 having a short pitch connecting section 224. Figure 19 is an enlarged view of section Q18 in Figure 15. Figure 20 is a perspective view illustrating the relationship between the long pitch connecting section 223 and the short pitch connecting section 224 with respect to the U1 coil section 31 and U2 coil section 32. Figure 21 is a perspective view illustrating the relationship between the standard pitch connecting sections 221 and 222 of the U3 coil section 33 and U4 coil section 34 and the long pitch connecting section 223 and the short pitch connecting section 224 of the U1 coil section 31 and U2 coil section 32.

[0076] As shown in Figure 14, the U-phase coil 30 is formed by arranging multiple types of coil pieces 70 and joining the legs 71 together at a joint 90 on the Z2 side, aligned radially. In this embodiment, the joints 90 are formed aligned radially (see also Figures 5 to 12).

[0077] Multiple types of coil pieces 70 include coil pieces 70 having standard pitch connecting sections 221 or 222 (also referred to as "coil piece 70A" for distinction) (see Figure 16), coil pieces 70 having long pitch connecting sections 223 (also referred to as "coil piece 70B" for distinction) (see Figure 17), and coil pieces 70 having short pitch connecting sections 224 (also referred to as "coil piece 70C" for distinction) (see Figure 18).

[0078] Two types of coil pieces 70A are provided, depending on the difference in their radial insertion position (turn position). Since the two types of coil pieces 70A differ only slightly in their circumferential dimensions, unless otherwise specified, the description below will focus on the one equipped with the standard pitch connecting section 221.

[0079] The coil piece 70A has a pair of slot accommodating portions 21. The pair of slot accommodating portions 21 are inserted into two slots 11 that are spaced apart in the circumferential direction by a number of slots corresponding to the standard slot pitch, as described above.

[0080] As shown in Figure 16, the coil piece 70A has a standard pitch connecting portion 221 on the Z1 side. The standard pitch connecting portion 221 is bent and formed so as to be offset radially by one turn.

[0081] The standard pitch crossover section 221 has a top portion 2210 located on the outermost axial side. The top portion 2210 is set at or near the circumferential midpoint of the coil piece 70A.

[0082] As shown in Figure 19, the coil pieces 70A are arranged in parallel and offset radially and circumferentially. For example, the coil pieces 70A of the U1 coil section 31 and the coil pieces 70A of the U3 coil section 33 may be arranged with their respective standard pitch connecting sections 221 offset by one slot in the circumferential direction and one turn in the radial direction, as shown in Figure 19.

[0083] As shown in Figure 16, each coil piece 70A has two legs 71 (also referred to as "legs 710A and 711A" for distinction) that are continuous with the pair of slot housings 21 on the Z2 side. The legs 710A and 711A are bent and formed in a direction that brings them closer to each other in the circumferential direction (i.e., in the circumferential direction in which they extend in opposite directions). The joint portion 90 related to the coil piece 70A is set at or near the circumferential intermediate position of the coil piece 70A (see Figure 5, etc.). Coil pieces 70A inserted into the same pair of slots 11 are joined in such a manner that they are electrically in series in the same phase. The joint portions 90 related to coil pieces 70A inserted into the same pair of slots 11 are aligned radially at the same circumferential position (see Figure 14).

[0084] As shown in Figure 17, the coil piece 70B has a pair of slot housings 21 (hereinafter referred to as "slot housings 210B, 211B" when distinguishing them). As described above, the slot housings 210B, 211B are inserted into two slots 11 that are separated by 7 slots in the circumferential direction.

[0085] As shown in Figure 17, the coil piece 70B has a long-pitch connecting section 223 on the Z1 side. The long-pitch connecting section 223 is bent and formed so as to be offset radially by 6 turns, as described above.

[0086] The long-pitch crossover section 223 has a top portion 2230 (hereinafter also referred to as the "long-pitch top portion 2230") located on the outermost axial side. The long-pitch top portion 2230 extends radially and circumferentially. The long-pitch top portion 2230 is set at a position offset circumferentially from the circumferential midpoint of the coil piece 70B. Specifically, the long-pitch top portion 2230 is located circumferentially closer to the slot housing portion 210B with respect to the circumferential midpoint of the coil piece 70B. Unlike the short-pitch top portion 2240 described later, the long-pitch top portion 2230 extends over a relatively short circumferential section.

[0087] The long-pitch connecting portion 223 has non-top portions (hereinafter also referred to as "long-pitch non-top portions 2231, 2232") on both sides of the long-pitch top portion 2230 in the circumferential direction. The long-pitch non-top portions 2231, 2232 have root portions (hereinafter also referred to as "long-pitch root portions 2233, 2234") that extend axially continuously from the slot housing portion 21. The axially inner ends of the long-pitch root portions 2233, 2234 (boundaries with the slot housing portion 21) are located at the same radial position as the slot housing portion 21, and extend axially from the axially inner ends outwards. The axial lengths of the long-pitch root portions 2233, 2234 are relatively short. The portion of the long-pitch non-top portion 2231 excluding the long-pitch root portion 2233 forms an oblique portion that extends circumferentially and axially outwards from the long-pitch root portion 2233. Similarly, the portion of the long-pitch non-top portion 2232 excluding the long-pitch root portion 2234 forms an oblique portion that extends circumferentially and axially outward from the long-pitch root portion 2234.

[0088] The long-pitch non-top portion 2231 is offset radially inward by 6 turns relative to the long-pitch non-top portion 2232. Such an offset may be achieved in the section relating to the long-pitch top portion 2230.

[0089] As shown in Figure 17, the coil piece 70B has two legs 71 (also referred to as "legs 710B and 711B" for distinction) that are continuous with the pair of slot housings 210B and 211B on the Z2 side. The legs 710B and 711B are bent in the circumferential direction so that they extend in opposite directions from each other. On the Z2 side, the coil piece 70B is joined to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 221) at one end in the circumferential direction, and to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 222) at the other end in the circumferential direction.

[0090] The coil piece 70C has a pair of slot housings 21 (hereinafter referred to as "slot housings 210C, 211C" when distinguishing them). As described above, the slot housings 210C, 211C are inserted into two slots 11 that are separated by 5 slots in the circumferential direction.

[0091] As shown in Figure 18, the coil piece 70C has a short-pitch connecting section 224 on the Z1 side. The short-pitch connecting section 224 is bent and formed so as to be offset radially by 6 turns, as described above.

[0092] The short-pitch connecting section 224 has a top portion 2240 (hereinafter also referred to as the "short-pitch top portion 2240") located on the outermost side in the axial direction. The short-pitch top portion 2240 extends radially and circumferentially. In this embodiment, the short-pitch top portion 2240 extends radially for 7 turns. Specifically, the short-pitch top portion 2240 has a bent portion (indicated as 2240(B) in Figure 18) that bends radially outward between the end closer to the slot housing section 211C and the end closer to the slot housing section 210C (indicated as 2240(E) in Figure 18). In this case, the short-pitch top portion 2240 extends only in the circumferential direction from the bent portion (indicated as 2240(B) in Figure 18) to the end closer to the slot housing portion 211C, and extends radially outward while continuing to extend in the circumferential direction from the bent portion (indicated as 2240(B) in Figure 18) to the end closer to the slot housing portion 210C (indicated as 2240(E) in Figure 18). The end of the short-pitch top portion 2240 closer to the slot housing portion 210C (indicated as 2240(E) in Figure 18) is set at a position offset in the circumferential direction from the circumferential midpoint of the coil piece 70C. Specifically, this end of the short-pitch top portion 2240 (indicated as 2240(E) in Figure 18) is located circumferentially closer to the slot housing portion 210C with respect to the circumferential midpoint of the coil piece 70C. On the other hand, the end of the short-pitch top portion 2240 that is closer to the slot housing portion 211C is located near the circumferential position of the slot housing portion 211C.

[0093] The short-pitch connecting portion 224 has non-top portions (hereinafter also referred to as "short-pitch non-top portions 2241, 2242") on both sides of the short-pitch top portion 2240 in the circumferential direction. The short-pitch non-top portions 2241, 2242 have root portions (hereinafter also referred to as "short-pitch root portions 2243, 2244") that extend axially continuously from the slot housing portion 21. The axially inner ends of the short-pitch root portions 2243, 2244 (boundaries with the slot housing portion 21) are located at the same radial position as the slot housing portion 21, and extend axially from the axially inner ends outwards. In this embodiment, the short-pitch non-top portion 2242 has substantially no portion extending in the circumferential direction and consists of the pitch root portion 2244. On the other hand, the portion of the short-pitch non-top portion 2241 excluding the short-pitch root portion 2243 forms an oblique portion that extends circumferentially and axially outward from the short-pitch root portion 2243.

[0094] The short-pitch non-top portion 2241 is offset radially inward by 7 turns relative to the short-pitch non-top portion 2242. Such an offset may be achieved by the section relating to the short-pitch top portion 2240.

[0095] As shown in Figure 18, the coil piece 70C has two legs 71 (also referred to as "legs 710C and 711C" for distinction) that are continuous with the pair of slot housings 210C and 211C on the Z2 side. The legs 710C and 711C are bent in the circumferential direction so that they extend in opposite directions from each other. On the Z2 side, the coil piece 70C is joined to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 221) at one end in the circumferential direction, and to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 222) at the other end in the circumferential direction.

[0096] In this embodiment, the coil piece 70C is arranged such that the circumferential range of the short-pitch connecting portion 224 is included within the circumferential range of the long-pitch connecting portion 223 relative to the coil piece 70B. Furthermore, the slot 11 into which the slot housing portion 210C is inserted and the slot 11 into which the slot housing portion 210B is inserted are adjacent in the circumferential direction, and the slot 11 into which the slot housing portion 211C is inserted and the slot 11 into which the slot housing portion 211B is inserted are adjacent in the circumferential direction.

[0097] Incidentally, when realizing such a relationship (arrangement) between the long-pitch connecting section 223 and the short-pitch connecting section 224, unlike the configuration of this embodiment described below, it is also possible to extend the long-pitch connecting section axially outward from the short-pitch connecting section along its entire circumferential direction. However, in such a configuration, the long-pitch connecting section and the short-pitch connecting section would form a two-story structure, leading to an increase in axial size.

[0098] In contrast, in this embodiment, the increase in body size in the axial direction can be suppressed by adopting the following configuration.

[0099] In other words, in this embodiment, the long-pitch crown portion 2230 and the short-pitch crown portion 2240 do not intersect in the axial direction, as shown in Figure 20. This makes it possible to have the same axial position for the long-pitch crown portion 2230 and the short-pitch crown portion 2240, and as a result, it is possible to reduce the axial size.

[0100] As shown in Figure 21, the long-pitch top portion 2230 and the short-pitch top portion 2240 are located axially outward from the top portion 2210 of the standard-pitch connecting portion 221. The coil pieces 70B and 70C extend circumferentially, straddling the standard-pitch connecting portion 221 radially from the axially outward side.

[0101] In this embodiment, the long-pitch top portion 2230 is located closer to the slot housing portion 210B in the circumferential direction than the short-pitch top portion 2240. This ensures that the long-pitch top portion 2230 and the short-pitch top portion 2240 do not overlap when viewed in the axial direction. However, in a modified example, the opposite arrangement may be used. That is, the long-pitch top portion 2230 may be located further away from the slot housing portion 210B in the circumferential direction than the short-pitch top portion 2240.

[0102] Furthermore, in this embodiment, the short-pitch root portion 2244 is offset radially outward midway through (within the axial range of the short-pitch root portion 2244). Specifically, the short-pitch root portion 2244 has a bent-formed portion 2245 that extends radially outward, and by having the bent-formed portion 2245, it is offset radially outward by approximately one turn. As a result, as shown in Figure 20, the short-pitch root portion 2244 can intersect the long-pitch connecting portion 223 from the radially outward direction when viewed radially from the radially outward direction. In addition, the long-pitch non-top portion 2232 of the long-pitch connecting portion 223 can extend circumferentially to the long-pitch top portion 2230 by passing axially inside the short-pitch top portion 2240 of the short-pitch connecting portion 224. In particular, in this embodiment, since the short-pitch top portion 2240 substantially starts from the circumferential position of the pitch root portion 2244, the long-pitch non-top portion 2232 of the long-pitch connecting portion 223 easily passes axially inside the short-pitch top portion 2240. This makes it possible to reduce the axial size while ensuring the necessary clearance between the long-pitch non-top portion 2232 and the short-pitch top portion 2240.

[0103] Furthermore, the short-pitch base portion 2243 and the long-pitch base portion 2233 do not have a radial offset like the bent-formed portion 2245, as shown in Figure 20. The long-pitch non-top portion 2231 of the long-pitch connecting portion 223 extends circumferentially from the long-pitch base portion 2233, passing axially outside the short-pitch non-top portion 2241 of the short-pitch connecting portion 224, to the long-pitch top portion 2230.

[0104] In this embodiment, the short-pitch root portion 2244 is offset radially outward with respect to the first-turn slot housing portion 211C, and thus offset radially outward with respect to the first-turn slot housing portion 211B. Since the short-pitch root portion 2244 is offset radially outward, its axial length is set to be relatively long.

[0105] Furthermore, in this embodiment, the short-pitch root portion 2244 is offset radially outward with respect to the slot housing portion 211B of the first turn, but the short-pitch root portion 2243 may be offset radially inward with respect to the slot housing portion 210B of the sixth turn. However, the configuration in which the root portion from the first turn, which is the outermost turn in the radial direction, is offset radially outward is more advantageous than the configuration in which the root portion from the sixth turn, which is the innermost turn in the radial direction, is offset radially inward, because it is not constrained by the positional relationship with the rotor 150.

[0106] Next, other embodiments will be described with reference to Figure 22 and subsequent figures. For the purpose of distinction, the embodiment described above will also be referred to as "Embodiment 1," and the other embodiments described below will also be referred to as "Embodiment 2." In the description of Embodiment 2 below, components that may be the same as those in Embodiment 1 above may be given the same reference numerals and their description may be omitted.

[0107] Figures 22 and 23 show the configuration of the U1 coil section 31A of the U-phase coil 30A. Figures 24 and 25 show the configuration of the U2 coil section 32A of the U-phase coil 30A. Figures 26 and 27 show the configuration of the U3 coil section 33A of the U-phase coil 30A. Figures 28 and 29 show the configuration of the U4 coil section 34A of the U-phase coil 30A.

[0108] In Figures 22 to 29, the meanings of the numbers below the word "Turn" on the left and the numbers below the word "#" are the same as in Figures 5 to 12 mentioned earlier.

[0109] In Figures 22 to 29, the connecting section 22A on the Z1 side is shown as a solid line, and the connecting section 22A on the Z2 side is shown as a dotted line.

[0110] Figures 22 to 29 show the annular stator core 10 in an unfolded state, with the vertical direction being the radial direction (direction B) of the stator core 10 and the horizontal direction being the circumferential direction (direction A) of the stator core 10. That is, in Figures 22 and 23, the right end of Figure 22 and the left end of Figure 23 are connected to each other, and the left end of Figure 22 and the right end of Figure 23 are connected to each other. The same applies to Figures 24 and 25, Figures 26 and 27, and Figures 28 and 29. Although not shown in the illustrations, the V-phase coil 40A and the W-phase coil 50A are positioned in the stator core 10 with two and four slots 11 offset from the U-phase coil 30A, respectively.

[0111] In this embodiment, the U-phase coil 30A is wound around the stator core 10 using a short-pitch overlapping winding method. That is, the coil pitch is shorter than the magnetic pole pitch.

[0112] Specifically, as shown in Figures 22 to 29, the U-phase coil 30A is placed in slots #3, #4, #5, #9, #10, #11, #15, #16, #17, #21, #22, #23, #27, #28, #29, #33, #34, #35, #39, #40, #41, #45, #46, and #47 of the 48 slots 11. Here, slots 11 of #3, #4, and #5, slots 11 of #9, #10, and #11, slots 11 of #15, #16, and #17, slots 11 of #21, #22, and #23, slots 11 of #27, #28, and #29, slots 11 of #33, #34, and #35, slots 11 of #39, #40, and #41, and slots 11 of #45, #46, and #47 are each three adjacent slots 11 in the circumferential direction (direction A) (examples include the first or fourth slot and the second end slot, the central slot, and the second or third slot and the second end slot).

[0113] In this embodiment, the U-phase coil 30A is arranged for 6 turns in slots 11 of slots #3, #4, #5, #9, #10, #11, #15, #16, #17, #21, #22, #23, #27, #28, #29, #33, #34, #35, #39, #40, #41, #45, #46, and #47, specifically in slots #4, #10, #16, #22, #28, #34, #40, and #46. That is, in each of these slots 11, 6 slot housings 21 are arranged in a single line in the radial direction. The remaining slots 11 are arranged for 3 turns. That is, in each of these slots 11, 3 slot housings 21 are arranged in a line in the radial direction with a space of 1 turn between them. In addition, the slot housing section 21 for the coils of the other phases (V-phase coil 40 and W-phase coil 50) is located in this one-turn space.

[0114] In this embodiment, as described above, each slot housing 21 of the U-phase coil 30A is inserted into three adjacent slots 11 in the circumferential direction (direction A). The three slots 11 are arranged periodically along the circumferential direction with a 6-slot pitch (with a gap of 4 slots). Hereinafter, the slot 11 in the circumferential center of the three adjacent slots 11 in the circumferential direction (direction A) will also be referred to as the "center slot 11". Of the slots 11 on either side of the center slot 11, the slot 11 closer to slot #1 in ascending order will also be referred to as the "first side slot 11", and the slot 11 further from slot #1 will also be referred to as the "second side slot 11".

[0115] In this embodiment, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A are not configured such that the multiple slot housing sections 21 are concentrated only in the central slot 11, nor are the multiple slot housing sections 21 concentrated only in one of the first side slot 11 and the second side slot 11. In other words, the multiple slot housing sections 21 are distributed among the central slot 11, the first side slot 11, and the second side slot 11.

[0116] Specifically, the U1 coil section 31A has slot housings 21 inserted into each of the slots 11 of #3, #11, #16, #22, #27, #35, #40, and #46. That is, it is evenly distributed among the four central slots 11, the two first side slots 11, and the two second side slots 11. The U1 coil section 31A is wound starting from the neutral wire terminal 62 in the A2 direction and is wound in a clockwise direction when viewed in the B2 direction.

[0117] The U2 coil section 32A has slot housings 21 inserted into each of the slots 11 of #4, #10, #15, #23, #28, #34, #39, and #47. That is, it is evenly distributed among the four central slots 11, the two first side slots 11, and the two second side slots 11. The U2 coil section 32A is wound starting from the neutral wire terminal 62 in the A2 direction and is wound in a clockwise direction when viewed in the Z2 direction.

[0118] The U3 coil section 33A has slot housings 21 inserted into each of the slots 11 of #4, #9, #17, #22, #28, #33, #41, and #46. That is, it is evenly distributed among the four central slots 11, the two first side slots 11, and the two second side slots 11. The U3 coil section 33A is wound starting from the neutral wire terminal 62 in the A1 direction and is wound in a counterclockwise direction when viewed in the B2 direction.

[0119] The U4 coil section 34A has slot housings 21 inserted into each of the slots 11 of #5, #10, #16, #21, #29, #34, #40, and #45. That is, it is evenly distributed among the four central slots 11, the two first side slots 11, and the two second side slots 11. The U4 coil section 34A is wound starting from the neutral wire terminal 62 in the A1 direction and is wound in a counterclockwise direction when viewed in the Z2 direction.

[0120] In this embodiment, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A are each distributed among the central slot 11, the first side slot 11, and the second side slot 11, with multiple slot housing sections 21 inserted. This makes it possible to reduce circulating current, similar to Embodiment 1 described above.

[0121] Furthermore, in this embodiment, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A do not have a configuration in which multiple slot accommodating sections 21 are inserted only at the 1st to 3rd turn positions or only at the 4th to 6th turn positions out of the 6 turns. Rather, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A each have a configuration in which multiple slot accommodating sections 21 are inserted distributed among the 1st to 6th turn positions.

[0122] Specifically, in the U1 coil section 31A, slot housings 21 are inserted in slots 11 of the same name, specifically in slots #11, #22, #35, and #46, at radial positions corresponding to the 1st, 3rd, and 5th turns. In addition, in the remaining slots 11 of the same name, slot housings 21 are inserted at radial positions corresponding to the 2nd, 4th, and 6th turns.

[0123] In the U2 coil section 32A, slot housings 21 are inserted in slots 11 of #4, #10, #15, #23, #28, #34, #39, and #47, specifically in slots #10, #23, #34, and #47, at radial positions corresponding to the 1st, 3rd, and 5th turns. In the remaining slots 11 of #4, #15, #28, and #39, slot housings 21 are inserted at radial positions corresponding to the 2nd, 4th, and 6th turns.

[0124] The same applies to the U3 coil section 33A and the U4 coil section 34A.

[0125] In this embodiment, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A each have multiple slot housing sections 21 inserted at positions 1 to 6 turns. This makes it possible to reduce the circulating current, similar to Embodiment 1 described above.

[0126] Furthermore, in this embodiment, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A do not have a configuration in which six turns of slot housing section 21 are concentrated and inserted into the corresponding slot 11. That is, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A each have a configuration in which three turns of slot housing section 21 are inserted into the corresponding slot 11. As a result, the U1 coil section 31A, U2 coil section 32A, U3 coil section 33A, and U4 coil section 34A each have multiple slot housing sections 21 arranged substantially evenly around the entire 360-degree circumference. This makes it possible to reduce circulating current, similar to Embodiment 1 described above.

[0127] Thus, this embodiment, like Embodiment 1 described above, achieves a characteristic configuration that contributes to minimizing the difference in back electromotive force (a configuration that enhances the uniformity of the parallel coil arrangement in the circumferential, radial, and axial directions), that is, a "parallel coil arrangement with high uniformity."

[0128] In this embodiment, the power lines of the U1 coil section 31A and the U2 coil section 32A are adjacent in the circumferential direction at the 6th turn (6th layer), and the power lines of the U3 coil section 33A and the U4 coil section 34A are adjacent in the circumferential direction at the 1st turn (1st layer). The neutral wire of the U1 coil section 31A and the neutral wire of the U2 coil section 32A are adjacent in the circumferential direction at the 1st turn from a slot different from the slot where the power lines are arranged. The neutral wire of the U3 coil section 33A and the neutral wire of the U4 coil section 34A are adjacent in the circumferential direction at the 6th turn from a slot different from the slot where the power lines are arranged.

[0129] In this embodiment as well, the connecting portion 22 on the Z2 side is joined at an intermediate position in the circumferential direction. In Figures 22 to 29, each connecting portion 90 related to the connecting portion 22 on the Z2 side is schematically shown by black circles (reference numeral 90 is assigned to only some of them). For example, the connecting portion 22A on the Z2 side between slot 11 of #11 and slot 11 of #16 has a connecting portion 90 at an intermediate position in the circumferential direction between slot 11 of #13 and slot 11 of #14.

[0130] In this embodiment, the connecting portion 22A on the Z1 side has four different forms. Specifically, the connecting portion 22A on the Z1 side consists of four types: connecting portion 221A, connecting portion 222A, connecting portion 223A, and connecting portion 224A. This makes it possible to minimize the number of molds required to form the connecting portion 22A on the Z1 side.

[0131] The connecting sections 221A and 222A are each formed continuously from a pair of slot housings 21 inserted into the slot 11 at a 5-slot pitch (an example of a standard slot pitch). The number "5" in the 5-slot pitch is smaller than the number of slots / number of poles (48 / 8 in this example), and hereinafter the 5-slot pitch will also be referred to as the "short-section slot pitch". Note that the connecting sections 221A and 222A only differ in their radial position and extend within the same circumferential range. For example, in the U1 coil section 31A, the connecting sections 221A and 222A extend between slot #11 and slot #16, between slot #22 and slot #27, between slot #35 and slot #40, and between slot #46 and slot #3, respectively.

[0132] The connecting sections 223A and 224A have a characteristic configuration that contributes to the highly uniform parallel coil arrangement described above.

[0133] Specifically, the connecting section 223A is formed continuously from a pair of slot housing sections 21 that are inserted into the slot 11 with an 8-slot pitch (an example of the first slot pitch) which is 3 slots larger than the short-slot pitch. Hereafter, the connecting section 223A will also be referred to as the "long-pitch connecting section 223A".

[0134] The pair of slot housing sections 21, which are continuous with the long-pitch connecting section 223A, are positioned at the innermost radial position (i.e., the 6th turn) and the outermost radial position (i.e., the 1st turn), respectively.

[0135] Specifically, in the U1 coil section 31A, the long-pitch connecting section 223A is formed continuously from the slot housing section 21 in slot #27 and the slot housing section 21 in slot #35. In this case, the slot housing section 21 in slot #27 that is continuous with the long-pitch connecting section 223A is located in the 6th turn. The slot housing section 21 in slot #35 that is continuous with the long-pitch connecting section 223A is located in the 1st turn.

[0136] In the U1 coil section 31A, the slot housing 21 of the 6th turn in slot 11 of #3 is connected to the power line terminal 61, and the slot housing 21 of the 1st turn in slot 11 of #11 is connected to the neutral wire terminal 62. Therefore, in the U1 coil section 31A, there is only one long-pitch connecting section 223A.

[0137] In the U2 coil section 32A, there are two long-pitch connecting sections 223A. The first long-pitch connecting section 223A is formed continuously from the slot housing section 21 of the 6th turn in slot 11 of #15 and the slot housing section 21 of the 1st turn in slot 11 of #23. The second long-pitch connecting section 223A is formed continuously from the slot housing section 21 of the 6th turn in slot 11 of #39 and the slot housing section 21 of the 1st turn in slot 11 of #47.

[0138] In the U3 coil section 33A, there are two long-pitch connecting sections 223A. The first long-pitch connecting section 223A is formed continuously from the slot housing section 21 of the 6th turn in the #9 slot 11 and the slot housing section 21 of the 1st turn in the #17 slot 11. The second long-pitch connecting section 223A is formed continuously from the slot housing section 21 of the 6th turn in the #33 slot 11 and the slot housing section 21 of the 1st turn in the #41 slot 11.

[0139] In the U4 coil section 34A, the long-pitch connecting section 223A is formed continuously from the slot housing section 21 of the 6th turn in the #21 slot 11 and the slot housing section 21 of the 1st turn in the #29 slot 11.

[0140] In the U4 coil section 34A, the slot housing 21 of the 6th turn in slot 11 of #45 is connected to the neutral wire terminal 62, and the slot housing 21 of the 1st turn in slot 11 of #5 is connected to the power line terminal 61. Therefore, in the U4 coil section 34A, there is only one long-pitch connecting section 223A.

[0141] The connecting section 224A is formed continuously from a pair of slot housing sections 21 that are inserted into the slot 11 with a slot pitch of 6 (an example of a second slot pitch) which is one slot larger than the short-slot slot pitch. Hereinafter, the connecting section 224A will also be referred to as the "short-pitch connecting section 224A".

[0142] The pair of slot housing sections 21, which are continuous with the short-pitch connecting section 224A, are positioned at the innermost radial position (i.e., the 6th turn) and the outermost radial position (i.e., the 1st turn), respectively.

[0143] Specifically, in the U1 coil section 31A, there are two short-pitch connecting sections 224A. The first short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #16 slot 11 and the slot housing section 21 of the 1st turn in the #22 slot 11. The second short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #40 slot 11 and the slot housing section 21 of the 1st turn in the #46 slot 11.

[0144] In the U2 coil section 32A, the short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #28 slot 11 and the slot housing section 21 of the 1st turn in the #34 slot 11.

[0145] In the U2 coil section 32A, the slot housing 21 of the 6th turn in slot 11 of #4 is connected to the power line terminal 61, and the slot housing 21 of the 1st turn in slot 11 of #10 is connected to the neutral wire terminal 62. Therefore, in the U2 coil section 32A, there is only one short-pitch connecting section 224A.

[0146] In the U3 coil section 33A, the short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #22 slot 11 and the slot housing section 21 of the 1st turn in the #28 slot 11.

[0147] In the U3 coil section 33A, the slot housing 21 of the 6th turn in slot 11 of #46 is connected to the neutral wire terminal 62, and the slot housing 21 of the 1st turn in slot 11 of #4 is connected to the power line terminal 61. Therefore, in the U3 coil section 33A, there is only one short-pitch connecting section 224A.

[0148] In the U4 coil section 34A, there are two short-pitch connecting sections 224A. The first short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #10 slot 11 and the slot housing section 21 of the 1st turn in the #16 slot 11. The second short-pitch connecting section 224A is formed continuously from the slot housing section 21 of the 6th turn in the #34 slot 11 and the slot housing section 21 of the 1st turn in the #40 slot 11.

[0149] In this embodiment as well, the coil piece having a connecting portion 221A (not shown) and the coil piece having a connecting portion 222A (not shown) have a pair of slot housing portions 21 that are inserted into the same slot 11. The coil piece having a long-pitch connecting portion 223A (not shown) has one end joined to the coil piece having a connecting portion 221A (not shown) and the other end joined to the coil piece having a connecting portion 222A (not shown). Similarly, the coil piece having a short-pitch connecting portion 224A (not shown) has one end joined to the coil piece having a connecting portion 221A (not shown) and the other end joined to the coil piece having a connecting portion 222A (not shown).

[0150] Furthermore, in this embodiment as well, the coil piece (not shown) having a long-pitch connecting portion 223A and the coil piece (not shown) having a short-pitch connecting portion 224A can have the same characteristics as the coil piece 70B and coil piece 70C according to Embodiment 1 described above.

[0151] For example, although not shown, a coil piece (not shown) having a long-pitch connecting section 223A and a coil piece (not shown) having a short-pitch connecting section 224A can have their respective tops positioned in the same axial direction. That is, the axial positions of their respective tops can be made the same, and as a result, the axial size can be reduced.

[0152] Furthermore, the base of a coil piece (not shown) equipped with a short-pitch connecting section 224A may be offset radially outward with respect to the slot housing section 211B of the first turn. This allows the short-pitch connecting section 224A to intersect the long-pitch connecting section 223A from the radially outward direction when viewed radially from the radially outward direction at its base. In addition, the non-top portion of the long-pitch connecting section 223A can extend circumferentially to its top portion by passing axially inward from the non-top portion of the short-pitch connecting section 224A.

[0153] Next, another embodiment (hereinafter referred to as "Embodiment 3") will be described with reference to Figure 30 and subsequent figures.

[0154] Figure 30 is a perspective view of the stator 100B according to Embodiment 3. Figure 31 is an enlarged view of the stator coil 20B according to Embodiment 3, viewed from the radially inner side. Figure 32 is a perspective view of all the coil pieces 70U that form the U-phase coil 30U of the stator coil 20B according to Embodiment 3, Figure 33 is a perspective view of a coil piece 70 (also referred to as "coil piece 70D" for distinction) that has a long-pitch connecting section 223D, and Figure 34 is a perspective view of a coil piece 70 (also referred to as "coil piece 70E" for distinction) that has a short-pitch connecting section 224D. Figure 35 is a perspective view illustrating the relationship between the long-pitch connecting section 223D and the short-pitch connecting section 224D with respect to the U1 coil section 31U and the U2 coil section 32U. Figure 36 is a perspective view illustrating the relationship between the standard pitch connecting sections 221 and 222 of the U3 coil section 33U and the U4 coil section 34U, and the long pitch connecting section 223D and the short pitch connecting section 224D of the U1 coil section 31U and the U2 coil section 32U.

[0155] The stator 100B according to Example 3 differs from the stator 100 according to Example 1 described above in that the stator coil 20 is replaced with a stator coil 20B.

[0156] The stator coil 20B according to Example 3 differs from the stator coil 20 according to Example 1 described above mainly in that coil piece 70B is replaced with coil piece 70D, and coil piece 70C is replaced with coil piece 70E.

[0157] In the following description of coil piece 70D, components that may be the same as those of coil piece 70B according to Embodiment 1 described above may be given the same reference numerals and their descriptions may be omitted. Similarly, in the following description of coil piece 70E, components that may be the same as those of coil piece 70D according to Embodiment 1 described above may be given the same reference numerals and their descriptions may be omitted.

[0158] The coil piece 70D has a pair of slot housings 21 (slot housings 210B, 211B).

[0159] As shown in Figure 33, the coil piece 70D has a long-pitch connecting portion 223D on the Z1 side. In Embodiment 3, the long-pitch connecting portion 223D is bent and formed so that it is radially offset by 7 turns.

[0160] The long-pitch crossover section 223D has a top portion 2230D (hereinafter also referred to as the "long-pitch top portion 2230D") located on the outermost axial side. The long-pitch top portion 2230D is set at a position offset in the circumferential direction from the circumferential midpoint of the coil piece 70D. Specifically, the long-pitch top portion 2230D is located on the side closer to the slot housing portion 210B in the circumferential direction relative to the circumferential midpoint of the coil piece 70D. Unlike the short-pitch top portion 2240E, which will be described later, the long-pitch top portion 2230D extends over a relatively long circumferential section.

[0161] The long-pitch connecting portion 223D has non-top portions (hereinafter also referred to as "long-pitch non-top portions 2231D, 2232D") on both sides of the long-pitch top portion 2230D in the circumferential direction. The long-pitch non-top portions 2231D, 2232D have root portions (hereinafter also referred to as "long-pitch root portions 2233D, 2234D") that extend axially continuously from the slot housing portion. The long-pitch root portions 2233D, 2234D extend in the axial direction. The portion of the long-pitch non-top portion 2231D excluding the long-pitch root portion 2233D forms an oblique portion that extends circumferentially and axially outward from the long-pitch root portion 2233D. Similarly, the portion of the long-pitch non-top portion 2232D excluding the long-pitch root portion 2234D forms an oblique portion that extends circumferentially and axially outward from the long-pitch root portion 2234D.

[0162] The long-pitch non-top section 2231D is offset radially inward by 7 turns relative to the long-pitch non-top section 2232D. Such an offset may be achieved in the section of the long-pitch top section 2230D.

[0163] As shown in Figure 33, the coil piece 70D has two legs 71 (legs 710B and 711B) on the Z2 side that are continuous with the pair of slot housings 210B and 211B, respectively. The legs 710B and 711B are bent in the circumferential direction so that they extend in opposite directions relative to each other. On the Z2 side, the coil piece 70D is joined to the coil piece 70A (coil piece 70A with a standard pitch connecting portion 221) at one end in the circumferential direction, and to the coil piece 70A (coil piece 70A with a standard pitch connecting portion 222) at the other end in the circumferential direction.

[0164] As shown in Figure 34, the coil piece 70E has a pair of slot accommodating sections 21 (slot accommodating sections 210C, 211C). The slot accommodating sections 210C, 211C are inserted into two slots 11 that are separated by 5 slots in the circumferential direction, as described above.

[0165] As shown in Figure 34, the coil piece 70E has a short-pitch connecting section 224E on the Z1 side. The short-pitch connecting section 224E is bent and formed so as to be offset radially by 6 turns, as described above.

[0166] The short-pitch connecting section 224E has a top portion 2240E (hereinafter also referred to as "short-pitch top portion 2240E") located on the outermost axial side. The short-pitch top portion 2240E extends radially and circumferentially. In Embodiment 3, the short-pitch top portion 2240E extends radially for 6 turns.

[0167] The short-pitch connecting portion 224E has non-top portions (hereinafter also referred to as "short-pitch non-top portions 2241E, 2242E") on both sides of the short-pitch top portion 2240E in the circumferential direction. The short-pitch non-top portions 2241E, 2242E have root portions (hereinafter also referred to as "short-pitch root portions 2243E, 2244E") that extend axially continuously from the slot housing portion. The short-pitch root portions 2243E, 2244E extend in the axial direction. In Embodiment 3, the portion of the short-pitch non-top portion 2241E excluding the short-pitch root portion 2243E forms an oblique portion that extends circumferentially and axially outward from the short-pitch root portion 2243E. Furthermore, the portion of the short-pitch non-top portion 2242E excluding the short-pitch root portion 2244E forms an oblique portion extending circumferentially and axially outward from the short-pitch root portion 2244E. The portion of the short-pitch non-top portion 2241E excluding the short-pitch root portion 2243E (an example of a second oblique portion) and the portion of the long-pitch non-top portion 2231D excluding the long-pitch root portion 2233D (an example of a first oblique portion) are parallel to each other (see Figure 31).

[0168] The short-pitch non-top section 2241E is offset radially inward by 6 turns relative to the short-pitch non-top section 2242E. Such an offset may be achieved by the section of the short-pitch top section 2240E.

[0169] As shown in Figure 34, the coil piece 70E has two legs 71 (also referred to as "legs 710C and 711C" for distinction) that are continuous with the pair of slot housings 210C and 211C on the Z2 side. The legs 710C and 711C are bent in the circumferential direction so that they extend in opposite directions relative to each other. On the Z2 side, the coil piece 70E is joined to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 221) at one end in the circumferential direction, and to the coil piece 70A (a coil piece 70A with a standard pitch connecting portion 222) at the other end in the circumferential direction.

[0170] In this embodiment 3, the coil piece 70E is arranged such that the circumferential range of the short-pitch connecting portion 224E is included within the circumferential range of the long-pitch connecting portion 223D relative to the coil piece 70D. Furthermore, the slot 11 into which the slot housing portion 210C is inserted and the slot 11 into which the slot housing portion 210B is inserted are adjacent in the circumferential direction, and the slot 11 into which the slot housing portion 211C is inserted and the slot 11 into which the slot housing portion 211B is inserted are adjacent in the circumferential direction.

[0171] In Example 3, the following configuration can be used to suppress the increase in axial size related to the coil end on the Z1 side.

[0172] In other words, in Example 3, the long-pitch top portion 2230D and the short-pitch top portion 2240E do not overlap in the axial direction, similar to Example 1 described above. That is, as shown in Figure 35, the long-pitch top portion 2230D and the short-pitch top portion 2240E are at different circumferential positions. This makes it possible to have the same axial position for the long-pitch top portion 2230D and the short-pitch top portion 2240E, and as a result, the axial size of the coil end on the Z1 side can be reduced.

[0173] As shown in Figure 36, the long-pitch top portion 2230D and the short-pitch top portion 2240E are located axially outward from the top portion 2210 of the standard-pitch connecting portion 221. The coil pieces 70D and 70E extend circumferentially, straddling the standard-pitch connecting portion 221 radially from the axially outward side.

[0174] In Embodiment 3, the long-pitch top portion 2230D is located closer to the slot housing portion 210B in the circumferential direction than the short-pitch top portion 2240E. This results in different circumferential positions for the long-pitch top portion 2230D and the short-pitch top portion 2240E. However, in a modified example, the arrangement may be reversed. That is, the long-pitch top portion 2230D may be located further away from the slot housing portion 210B in the circumferential direction than the short-pitch top portion 2240E.

[0175] Furthermore, in Example 3, the long-pitch root portion 2234D is offset radially outward midway through its length (within the axial range of the long-pitch root portion 2234D). Specifically, the long-pitch root portion 2234D has a bent-formed portion 2235D that is bent radially outward, and by having the bent-formed portion 2235D, it is offset radially outward by approximately one turn. Note that because the long-pitch root portion 2234D is offset radially outward, its axial length is set to be longer than that of the short-pitch root portion 2244E.

[0176] In Example 3, having such a bent portion 2235D, as shown in Figure 35, the long-pitch connecting portion 223D can intersect or overlap the short-pitch connecting portion 224E from the radially outside when viewed radially from the radially outside. In particular, the short-pitch non-top portion 2242E does not overlap with the long-pitch connecting portion 223D when viewed axially throughout its entire length. Similarly, the long-pitch non-top portion 2232D does not overlap with the short-pitch connecting portion 224E when viewed axially throughout its entire length. This makes it possible to improve the assembly of the coil pieces 70E and 70D while reducing the axial size of the coil end on the Z1 side.

[0177] Specifically, in Example 3, unlike Example 1 described above, as described above, the long-pitch connecting portion 223D and the short-pitch connecting portion 224E do not overlap in the axial direction with the long-pitch non-top portion 2232D and the short-pitch non-top portion 2242E. As a result, unlike Example 1 described above, the coil pieces 70D and 70E can be assembled in an independent manner, improving the ease of assembly compared to Example 1 described above. That is, in the case of Example 1 described above, the coil pieces 70B and 70C overlap (intersect) in the axial direction, so it is necessary to set and assemble the coil pieces 70B and 70C at the same time. In contrast, according to Example 3, the coil piece 70D and 70E can be assembled by assembling the coil piece 70E first, and then assembling the coil piece 70D.

[0178] Furthermore, the short-pitch base portion 2243E and the long-pitch base portion 2233D do not have a radial offset like the bent-formed portion 2245, as shown in Figure 35. The long-pitch non-top portion 2231D of the long-pitch connecting portion 223D extends circumferentially from the long-pitch base portion 2233D, passing axially outside the short-pitch non-top portion 2241E of the short-pitch connecting portion 224E, to the long-pitch top portion 2230D when viewed radially.

[0179] Furthermore, in Embodiment 3, the long-pitch root portion 2234D is offset radially outward with respect to the slot housing portion 211B of the first turn, but the long-pitch root portion 2234D may also be offset radially inward with respect to the slot housing portion 210B of the sixth turn. However, the configuration in which the root portion from the first turn, which is the outermost turn in the radial direction, is offset radially outward is more advantageous than the configuration in which the root portion from the sixth turn, which is the innermost turn in the radial direction, is offset radially inward, because it is not constrained by the positional relationship with the rotor 150.

[0180] Next, with reference to Figure 37 and subsequent figures, further characteristic features of Example 3 will be described.

[0181] Figure 37 is a plan view of a portion of the stator 100B as seen from the Z1 side, showing the relationship between the neutral line busbar 88 and the short-pitch top section 2240E. Figure 38 is a plan view of Figure 37 with the neutral line busbar 88 removed. Figure 39 is a plan view of another portion of the stator 100B as seen from the Z1 side, showing the relationship between the power line busbar 89 and the short-pitch top section 2240E. In Figure 39, for explanatory purposes, the neutral line busbar 88 is shown removed.

[0182] In Example 3, as shown in Figures 37 and 38, the short-pitch top portion 2240E has a smaller circumferential extension range (circumferential length) than the long-pitch top portion 2230D. That is, the inclination of the short-pitch top portion 2240E when viewed in the axial direction (amount of radial displacement per unit length in the circumferential direction) is greater than that of the long-pitch top portion 2230D.

[0183] As a result, as shown in Figures 37 and 39, the distance (space distance) between the various busbars, such as the neutral line busbar 88 and the power line busbar 89, and the short-pitch top portion 2240E can be shortened, thereby improving the insulation between different phases.

[0184] Specifically, as shown in Figures 37 and 38, the distance L37 between the neutral busbar 88 and the short-pitch top portion 2240E can be shortened. Although not shown in Figure 37, it can be seen that the distance L37 is shortened when the axial inclination of the short-pitch top portion 2240E is the same as the axial inclination of the long-pitch top portion 2230D. The joint between the neutral busbar 88 and the lead wire from the stator coil 20B is realized by welding or the like, and is the part where the insulating coating has been removed.

[0185] Similarly, as shown in Figure 39, the distance L39 between the power line busbar 89 and the short-pitch top portion 2240E can be shortened. Similarly, although not shown in Figure 39, if the axial inclination of the short-pitch top portion 2240E is the same as the axial inclination of the long-pitch top portion 2230D, the distance L39 will be shortened. Note that the joint between the power line busbar 89 and the lead wires from the stator coil 20B is realized by welding or the like, and is the part where the insulating coating has been removed.

[0186] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above.

[0187] Furthermore, in the above-described embodiment, the number of parallel connections is "4", a so-called "4Y" configuration, but the number of parallel connections may be any number other than 4 (for example, an even number). Note that the more parallel connections there are, the more advantageous it is to increase the current flowing through the rotating electric machine 200. For example, in the case of a so-called "2Y" configuration with "2" parallel connections, a winding configuration following that of the U1 coil section 31 and the U2 coil section 32 (or the U3 coil section 33 and the U4 coil section 34) may be used.

[0188] With regard to each of the above embodiments, the following additional information is disclosed.

[0189] [Note 1] A stator coil supplied with three-phase AC power, It comprises a stator core having multiple slots around which the stator coil is wound, The plurality of slots include a first slot and a second slot that are adjacent in the circumferential direction, and a third slot and a fourth slot that are different from the first slot and the second slot and are adjacent in the circumferential direction. The first slot and the fourth slot are spaced apart in the circumferential direction by the first slot pitch. The second slot and the third slot are spaced apart in the circumferential direction with a second slot pitch smaller than the first slot pitch. The stator coil, in the same phase of the three phases, A first slot housing portion is located at the outermost radial position of the first slot, A first root portion that is continuous with the first slot housing portion and extends axially from the end face of the stator core, A second slot housing portion is located at the outermost radial position of the second slot, A second root portion that is continuous with the second slot housing portion and extends axially from the end face of the stator core, A third slot housing portion is located at the innermost radial position of the third slot, A third root portion that is continuous with the third slot housing portion and extends axially from the end face of the stator core, A fourth slot housing portion is located at the innermost radial position of the fourth slot, A fourth root portion that is continuous with the fourth slot housing portion and extends axially from the end face of the stator core, A first circumferential portion that extends in the circumferential direction and includes a first crown portion located on the outermost side in the axial direction, and integrally connects the first root portion and the fourth root portion via the first crown portion, A second circumferential portion extending in the circumferential direction and including a second crown portion located on the outermost side in the axial direction, integrally connecting the second root portion and the third root portion via the second crown portion, Includes, The first root portion and the second root portion are offset radially outward from the other, or The fourth root portion and the third root portion are offset radially inward from the other, A stator for a rotating electric machine in which the first and second top portions do not overlap in the axial direction.

[0190] Here, the first circumferential portion refers to the long-pitch top portion 2230 and the portions of the long-pitch non-top portions 2231 and 2232 excluding the long-pitch root portions 2233 and 2234 in the above-described embodiment. The second circumferential portion refers to the short-pitch top portion 2240 and the portions of the short-pitch non-top portions 2241 and 2242 excluding the short-pitch root portions 2243 and 2244 in the above-described embodiment.

[0191] [Note 2] The stator for a rotating electric machine as described in Appendix 1, wherein the first top portion and the second top portion do not overlap when viewed in the axial direction.

[0192] [Note 3] The stator for a rotating electric machine as described in Appendix 1, wherein the first top portion and the second top portion are in the same axial position.

[0193] [Note 4] The first non-top portion has a first oblique portion that extends axially and circumferentially, continuously from the slot housing portion at the innermost radial position of the first slot, The second non-top portion has a second oblique portion that extends axially and circumferentially, continuously from the slot housing portion at the innermost radial position of the second slot, The first oblique portion and the second oblique portion extend parallel to each other when viewed in the radial direction, in the stator for a rotating electric machine as described in Appendix 1.

[0194] [Note 5] The stator for a rotating electric machine as described in Appendix 1, wherein the first slot pitch is one slot larger than the second slot pitch.

[0195] [Note 6] The second root portion is offset radially outward with respect to the first root portion, and is a stator for a rotating electric machine as described in any one of the appendices 1 to 5.

[0196] [Note 7] The second crown portion extends radially and circumferentially, The first non-top portion is located axially inward from the second top portion, and is a stator for a rotating electric machine as described in Appendix 6.

[0197] [Note 8] The first circumferential portion further comprises a first inner non-vertical portion which is the portion between the first vertex portion and the fourth root portion, and a first outer non-vertical portion which is the portion between the first vertex portion and the first root portion. The second circumferential portion further comprises a second inner non-vertical portion which is the portion between the second vertex portion and the third root portion, and a second outer non-vertical portion which is the portion between the second vertex portion and the second root portion. The stator for a rotating electric machine as described in Appendix 6, wherein the first outer non-top portion is located axially inward of the second top portion, and the first inner non-top portion is located axially outward of the second inner non-top portion.

[0198] [Note 9] The first root portion is offset radially outward with respect to the second root portion, and is a stator for a rotating electric machine as described in any one of the appendices 1 to 5.

[0199] [Note 10] The stator for a rotating electric machine as described in Appendix 9, wherein the second non-top portion, on the side of the circumferential direction of the second top portion that is closest to the slot housing portion at the outermost radial position of the second slot, does not overlap with the first connecting portion when viewed in the axial direction over its entire length.

[0200] [Note 11] The first crown portion extends radially and circumferentially, The stator for a rotating electric machine as described in Appendix 9, wherein the second top portion extends radially and circumferentially, and its circumferential length is shorter than that of the first top portion.

[0201] [Note 21] Stator coil and, It comprises a stator core having multiple slots around which the stator coil is wound, The stator coils have two or more parallel connections for each phase. A slot housing unit inserted into each corresponding slot among the plurality of slots, It has a connecting portion that is exposed from the axial end face of the stator core and extends circumferentially in a manner that connects the pair of slot housing portions, Each of the connecting portions on one side in the axial direction is formed by joining two legs from the slot housing portion of a standard slot pitch, The plurality of connecting portions on the other side in the axial direction include standard connecting portions formed integrally with the slot housing portions of the standard slot pitch, first connecting portions formed integrally with the slot housing portions of the first slot pitch, and second connecting portions formed integrally with the slot housing portions of the second slot pitch. The first slot pitch and the second slot pitch are different from the standard slot pitch, and the first slot pitch is larger than the second slot pitch. The pair of slot housings for the first slot pitch are positioned at the innermost radial position and the outermost radial position, respectively. The pair of slot housings for the second slot pitch are positioned at the innermost radial position and the outermost radial position, respectively. The first connecting portion has a first crown portion located on the outermost side in the axial direction, and first non-crown portions on both sides of the first crown portion in the circumferential direction. The second connecting portion has a second top portion located axially on the outermost side within the circumferential range of the first connecting portion, and second non-top portions on both sides of the second top portion in the circumferential direction. The aforementioned plurality of slots include a first slot and a second slot that are adjacent in the circumferential direction, The first non-top portion has a first root portion that extends axially continuously from the slot housing portion at the outermost or innermost radial position of the first slot, The second non-top portion has a second root portion that extends axially continuously from the slot housing portion at the same radial position as the first root portion in the second slot, A stator for a rotating electric machine, wherein the first root portion and the second root portion are offset radially outward or inward relative to the other.

[0202] [Note 22] The first and second top portions do not overlap when viewed in the axial direction (they are in different circumferential positions), as described in Appendix 21, for a stator for a rotating electric machine.

[0203] [Note 23] The stator for a rotating electric machine as described in Appendix 21, wherein the first top portion and the second top portion are in the same axial position.

[0204] [Note 24] The first non-top portion has a first oblique portion that extends axially and circumferentially, continuously from the slot housing portion at the innermost radial position of the first slot, The second non-top portion has a second oblique portion that extends axially and circumferentially, continuously from the slot housing portion at the innermost radial position of the second slot, The first oblique portion and the second oblique portion extend parallel to each other when viewed in the radial direction, and the stator for a rotating electric machine as described in any one of the appendices 21 to 23.

[0205] [Note 25] The first slot pitch is one slot larger than the standard slot pitch. A stator for a rotating electric machine as described in any one of appendices 21 to 24, wherein the second slot pitch is one slot smaller than the standard slot pitch.

[0206] [Note 26] The second root portion is offset radially outward with respect to the first root portion, and is a stator for a rotating electric machine as described in any one of the appendices 21 to 25.

[0207] [Note 27] The second crown portion extends radially and circumferentially, The stator for a rotating electric machine as described in Appendix 26, wherein the first non-top portion is located axially inward from the second top portion.

[0208] [Note 28] A stator for a rotating electric machine as described in Appendix 26 or 27, wherein the first non-top portion on the side of the circumferential direction of the first top portion that is closest to the slot housing at the outermost radial position of the first slot is located axially inward of the second top portion, and the first non-top portion on the side of the circumferential direction of the second top portion that is closest to the slot housing at the innermost radial position of the second slot is located axially outward of the second non-top portion on the side of the circumferential direction of the second top portion that is closest to the slot housing at the innermost radial position of the second slot.

[0209] [Note 29] The first root portion is offset radially outward with respect to the second root portion, and is a stator for a rotating electric machine as described in any one of appendices 21 to 25.

[0210] [Note 30] The stator for a rotating electric machine as described in Appendix 29, wherein the second non-top portion, on the side of the circumferential direction of the second top portion that is closest to the slot housing portion at the outermost radial position of the second slot, does not overlap with the first connecting portion when viewed in the axial direction over its entire length.

[0211] [Note 31] The first crown portion extends radially and circumferentially, The stator for a rotating electric machine according to Appendix 29 or 30, wherein the second top portion extends radially and circumferentially, and its circumferential length is shorter than that of the first top portion.

[0212] [Note 32] A stator core having multiple slots, The stator coil is wound around the stator core by overlapping windings, and each of the three phases has four parallel windings between the power supply side and the neutral wire. The stator coil is, A slot housing section is provided in each of the slots which are spaced apart in the circumferential direction, A connecting portion is exposed from one axial end face of the stator core, integrally connecting the slot housing portions and extending in the circumferential direction, The coil piece includes a leg portion that extends from the slot housing portion toward the opposite side of the connecting portion and protrudes from the other axial end face of the stator core, The aforementioned coil piece is The connecting portion is a standard coil piece having the standard slot pitch, The connecting portion has a first coil piece with a first slot pitch that is one slot larger than the standard slot pitch, The system includes a second coil piece in which the connecting portion has a second slot pitch that is one slot smaller than the standard slot pitch, and a plurality of other types. The aforementioned multiple slots are, A first slot is arranged in the circumferential direction with the standard slot pitch, and only the slot housing portion of the same phase among the three phases is arranged in the first slot, It includes a second slot adjacent to one side of the first slot in the circumferential direction, where the slot housings are arranged in the circumferential direction with the standard slot pitch, and where only the slot housings of the same phase among the three phases are arranged, The aforementioned parallel winding is, The slot housing portions of the standard coil piece are positioned at the positions excluding the innermost and outermost radially separated first slots, respectively, and the legs are joined together to form a first unit coil, which is formed by overlapping windings. The second unit coil is formed by arranging the slot-accommodating portions of the standard coil piece at positions excluding the innermost and outermost radially separated second slots, respectively, and joining the leg portions to form an overlapping winding, One slot-accommodating portion of the first coil piece is positioned at the radially outermost position of the first slot, and the other slot-accommodating portion of the first coil piece is positioned at the radially innermost position of the first slot. The leg portion of the first coil piece is joined to the leg portion at one end of the first unit coil, and the other leg portion of the first coil piece is joined to the leg portion at the other end of the second unit coil. One slot-accommodating portion of the second coil piece is positioned at the radially outermost position of the second slot, and the other slot-accommodating portion of the first coil piece is positioned at the radially innermost position of the second slot. A stator for a rotating electric machine, wherein one leg of the second coil piece is joined to the leg at one end of the second unit coil, and the other leg of the second coil piece is joined to the leg at the other end of the first unit coil.

[0213] [Note 33] The stator coil has, for each phase, a first coil section, a second coil section, a third coil section, and a fourth coil section connected in parallel to each other between the power supply side and the neutral wire. In each phase, the first coil section and the third coil section, and the second coil section and the fourth coil section, have opposite directions of current flow when viewed radially, from the power line to the neutral line, as described in Appendix 32, for a stator for a rotating electric machine.

[0214] [Note 34] The first and second slots are paired and arranged circumferentially in each phase at the standard slot pitch. A stator for a rotating electric machine as described in Appendix 32 or 33, wherein in each of the first to fourth coil sections, the first coil piece and the second coil piece are arranged alternately in the circumferential direction via the standard coil piece.

[0215] [Note 35] A stator for a rotating electric machine according to any one of the appendices 32 to 34, wherein in each of the first to fourth coil sections, the standard coil piece is inserted into only one of the first pair of first and second slots on the first circumferential side, and into only the other of the first pair of first and second slots on the second circumferential side.

[0216] [Note 36] In each of the first to fourth coil sections, the standard coil piece is inserted only into the other slot of the second pair of first and second slots adjacent to the first pair in the circumferential direction on the first circumferential side, and inserted only into the one slot of the second pair of first and second slots on the second circumferential side, as described in Appendix 35.

[0217] [Note 37] The first coil section and the third coil section are formed by inserting the standard coil pieces into the same first pair and second pair of first and second slots. The second coil section and the fourth coil section are formed by inserting the standard coil pieces into the same first pair and second pair of first and second slots. The stator for a rotating electric machine as described in Appendix 36, wherein the first pair and the second pair relating to the first coil section and the third coil section, and the first pair and the second pair relating to the second coil section and the fourth coil section, are offset in the circumferential direction by the standard slot pitch.

[0218] [Note 40] A stator core having multiple slots, The stator coil is wound around the stator core by short-section overlapping winding, and each of the three phases has four parallel windings between the power supply side and the neutral wire. The stator coil is, A slot housing section is provided in each of the slots which are spaced apart in the circumferential direction, A connecting portion is exposed from one axial end face of the stator core, integrally connecting the slot housing portions and extending in the circumferential direction, The coil piece includes a plurality of coil pieces, each including a leg portion that extends from the slot housing portion toward the opposite side of the connecting portion and protrudes from the other axial end face of the stator core, The plurality of coil pieces are, The connecting portion is a standard coil piece having the standard slot pitch, The connecting portion has a first coil piece with a first slot pitch that is three slots larger than the standard slot pitch, The system includes multiple types of second coil pieces, where the connecting portion has a second slot pitch that is one slot larger than the standard slot pitch, The four parallel windings mentioned above include a plurality of unit coil sections formed by joining standard coil pieces in series, One end of the aforementioned unit coil section and the other end of another aforementioned unit coil are connected in series via the first coil piece or the second coil piece. A stator for a rotating electric machine, wherein the first coil piece and the second coil piece are arranged alternately in the winding direction of each of the four parallel windings.

[0219] [Note 41] The plurality of slots include a first end slot, a central slot, and a second end slot that are sequentially continuous in the circumferential direction. Multiple standard coil pieces of the same phase are inserted into the central slot, arranged radially. The slot-accommodating portions of the standard coil pieces of two different phases are alternately inserted radially into the first end slot and the second end slot. The stator for a rotating electric machine as described in Appendix 40, wherein the first end slot, the central slot, and the second end slot form a group and are arranged circumferentially for each phase with the standard slot pitch.

[0220] [Note 42] In each of the first coil part to the fourth coil part, the standard coil piece is inserted only into the central slot of the first group on the first side in the circumferential direction, and is inserted only into one of the first end slot and the central slot of the first group on the second side in the circumferential direction. The stator for a rotating electrical machine according to Supplementary Note 41.

[0221] [Supplementary Note 43] In each of the first coil part to the fourth coil part, the standard coil piece is inserted only into the other slot of the first end slot and the central slot of the second group that is circumferentially adjacent to the first group on the first side in the circumferential direction, and is inserted only into the central slot of the second group on the second side in the circumferential direction. The stator for a rotating electrical machine according to Supplementary Note 42.

[0222] [Supplementary Note 52] A stator coil, A stator core having a plurality of slots, in which the stator coil is wound by overlapping winding, The stator coil has, for each phase, a first coil part, a second coil part, a third coil part, and a fourth coil part that are connected in parallel to each other between the power supply side and the neutral line. Slot accommodating parts inserted into corresponding slots among the plurality of slots, It has a bridging part that extends in the circumferential direction in a manner of connecting between the pair of slot accommodating parts, exposed from the axial end face of the stator core. Each of the bridging parts on one side in the axial direction is formed by joining two legs from the pair of slot accommodating parts with a standard slot pitch. The plurality of bridging parts on the other side in the axial direction include a standard bridging part formed integrally with the pair of slot accommodating parts with the standard slot pitch, a first bridging part formed integrally with the pair of slot accommodating parts with the first slot pitch, and a second bridging part formed integrally with the pair of slot accommodating parts with the second slot pitch. The first slot pitch is one slot larger than the standard slot pitch, and the second slot pitch is one slot smaller than the standard slot pitch. Each of the first to fourth coil sections is formed by a plurality of types of coil pieces, including a standard coil piece having the standard connecting portion, a first coil piece having the first connecting portion, and a second coil piece having the second connecting portion. The aforementioned plurality of slots include a first slot and a second slot that are adjacent in the circumferential direction, Multiple standard coil pieces of the same phase are inserted radially into the first and second slots, The first and second slots are paired and arranged circumferentially at a predetermined pitch for each phase. A stator for a rotating electric machine, wherein of a plurality of standard coil pieces inserted into the same pair of first and second slots, the radially outermost standard coil piece is joined on one side in the circumferential direction to one of the first and second coil pieces, and the radially innermost standard coil piece is joined on the other side in the circumferential direction to the other of the first and second coil pieces.

[0223] [Note 53] A stator for a rotating electric machine as described in Appendix 52, wherein in each phase, the first coil section and the third coil section, and the second coil section and the fourth coil section, have opposite directions of current flow when viewed radially, from the power line to the neutral line.

[0224] [Note 54] The predetermined pitch is the same as the standard slot pitch. A stator for a rotating electric machine as described in Appendix 52 or 53, wherein in each of the first to fourth coil sections, the first coil piece and the second coil piece are arranged alternately in the circumferential direction via the standard coil piece.

[0225] [Note 55] A stator for a rotating electric machine according to any one of the appendices 52 to 54, wherein in each of the first to fourth coil sections, the standard coil piece is inserted into only one of the first pair of first and second slots on the first circumferential side, and into only the other of the first pair of first and second slots on the second circumferential side.

[0226] [Note 56] In each of the first to fourth coil sections, the standard coil piece is inserted only into the other slot of the second pair of first and second slots adjacent to the first pair in the circumferential direction on the first circumferential side, and inserted only into the one slot of the second pair of first and second slots on the second circumferential side, as described in Appendix 55.

[0227] [Note 57] The first coil section and the third coil section are formed by inserting the standard coil pieces into the same first pair and second pair of first and second slots. The second coil section and the fourth coil section are formed by inserting the standard coil pieces into the same first pair and second pair of first and second slots. The stator for a rotating electric machine as described in Appendix 56, wherein the first pair and the second pair relating to the first coil section and the third coil section, and the first pair and the second pair relating to the second coil section and the fourth coil section, are offset in the circumferential direction by the predetermined pitch.

[0228] [Note 60] Stator coil and, The system comprises a stator core having multiple slots, in which the stator coil is wound by short-section overlapping winding, The stator coil has, for each phase, a first coil section, a second coil section, a third coil section, and a fourth coil section connected in parallel to each other between the power supply side and the neutral wire. A slot housing unit inserted into each corresponding slot among the plurality of slots, It has a connecting portion that is exposed from the axial end face of the stator core and extends circumferentially in a manner that connects the pair of slot housing portions, Each of the connecting portions on one side in the axial direction is formed by joining two legs from the slot housing portion of a standard slot pitch, The plurality of connecting portions on the other side in the axial direction include standard connecting portions formed integrally with the slot housing portions of the standard slot pitch, first connecting portions formed integrally with the slot housing portions of the first slot pitch, and second connecting portions formed integrally with the slot housing portions of the second slot pitch. The first slot pitch is three slots larger than the standard slot pitch, and the second slot pitch is one slot larger than the standard slot pitch. Each of the first to fourth coil sections is formed by a plurality of types of coil pieces, including a standard coil piece having the standard connecting portion, a first coil piece having the first connecting portion, and a second coil piece having the second connecting portion. The plurality of slots include a first end slot, a central slot, and a second end slot that are sequentially continuous in the circumferential direction. Multiple standard coil pieces of the same phase are inserted into the central slot, arranged radially. The slot-accommodating portions of the standard coil pieces of two different phases are alternately inserted radially into the first end slot and the second end slot. The first end slot, the central slot, and the second end slot form a group and are arranged along the circumferential direction at a predetermined pitch for each phase. A stator for a rotating electric machine, wherein of a plurality of standard coil pieces inserted into the same pair of slots, the radially outermost standard coil piece is joined on one side in the circumferential direction to one of the first coil piece and the second coil piece, and the radially innermost standard coil piece is joined on the other side in the circumferential direction to the other of the first coil piece and the second coil piece.

[0229] [Appendix 61] The predetermined pitch is the same as the standard slot pitch, In each of the first to fourth coil portions, the first coil piece and the second coil piece are alternately arranged in the circumferential direction via the standard coil piece, the stator for a rotating electric machine according to Appendix 60.

[0230] [Appendix 62] In each of the first to fourth coil portions, the standard coil piece is inserted only into the central slot of the first group on the first side in the circumferential direction, and is inserted only into one of the first end slot and the central slot of the first group on the second side in the circumferential direction, the stator for a rotating electric machine according to Appendix 61.

[0231] [Appendix 63] In each of the first to fourth coil portions, the standard coil piece is inserted only into the other slot of the first end slot and the central slot of the second group that is circumferentially adjacent to the first group on the first side in the circumferential direction, and is inserted only into the central slot of the second group on the second side in the circumferential direction, the stator for a rotating electric machine according to Appendix 62.

Explanation of Signs

[0232] 10 Stator core, 20 Stator coil, 11 Slot, 21 Slot housing, 210B Slot housing (1st slot housing), 210C Slot housing (2nd slot housing), 211C Slot housing (3rd slot housing), 211B Slot housing (4th slot housing), 22 Connecting section, 221, 222 Standard pitch connecting section, 223 Long pitch connecting section (1st connecting section), 224 Short pitch connecting section (2nd connecting section), 2230 Long pitch top section (1st top section, part of the 1st circumferential section), 2240 Short pitch top section (2nd top section, part of the 2nd circumferential section), 2231, 2232 Long pitch non-top section (1st non-top section, remaining part of the 1st circumferential section), 2241, 2242 Short-pitch non-vertical section (second non-vertical section, remaining part of the second circumferential section), 2233 long-pitch root section (first root section), 2243 short-pitch root section (second root section), 2244 short-pitch root section (third root section), 2234 long-pitch root section (fourth root section)

Claims

1. A stator coil supplied with three-phase AC power, It comprises a stator core having multiple slots around which the stator coil is wound, The plurality of slots include a first slot and a second slot that are adjacent in the circumferential direction, and a third slot and a fourth slot that are different from the first slot and the second slot and are adjacent in the circumferential direction. The first slot and the fourth slot are spaced apart in the circumferential direction by the first slot pitch. The second slot and the third slot are spaced apart in the circumferential direction with a second slot pitch smaller than the first slot pitch. The stator coil, in the same phase of the three phases, A first slot housing portion is positioned at the outermost radial position of the first slot, A first root portion that is continuous with the first slot housing portion and extends axially from the end face of the stator core, A second slot housing portion is located at the outermost radial position of the second slot, A second root portion that is continuous with the second slot housing portion and extends axially from the end face of the stator core, A third slot housing portion is located at the innermost radial position of the third slot, A third root portion that is continuous with the third slot housing portion and extends axially from the end face of the stator core, A fourth slot housing portion is located at the innermost radial position of the fourth slot, A fourth root portion that is continuous with the fourth slot housing portion and extends axially from the end face of the stator core, A first circumferential portion that extends in the circumferential direction and includes a first crown portion located on the outermost side in the axial direction, and integrally connects the first root portion and the fourth root portion via the first crown portion, A second circumferential portion extends in the circumferential direction and includes a second crown portion located on the outermost side in the axial direction, integrally connecting the second root portion and the third root portion via the second crown portion, Includes, The first root portion and the second root portion are offset radially outward from the other, or The fourth root portion and the third root portion are offset radially inward from the other. A stator for a rotating electric machine in which the first and second top portions do not overlap in the axial direction.

2. The stator for a rotating electric machine according to claim 1, wherein the first top portion and the second top portion are in the same axial position.

3. The first circumferential portion has a first inner non-vertical portion which is the portion between the first vertex portion and the fourth root portion, and the first inner non-vertical portion has a first oblique portion which extends axially and circumferentially continuously from the fourth root portion. The second circumferential portion has a second inner non-vertical portion which is the portion between the second vertex portion and the third root portion, and the second inner non-vertical portion has a second oblique portion which extends axially and circumferentially continuously from the third root portion. The stator for a rotating electric machine according to claim 1, wherein the first oblique portion and the second oblique portion extend parallel to each other along the radial direction.

4. The stator for a rotating electric machine according to claim 1, wherein the first slot pitch is two slots larger than the second slot pitch.

5. The stator for a rotating electric machine according to any one of claims 1 to 4, wherein the second root portion is offset radially outward with respect to the first root portion.

6. The second crown portion extends radially and circumferentially, The first circumferential portion further has first non-crown portions on both sides of the first crown portion in the circumferential direction, The stator for a rotating electric machine according to claim 5, wherein the first non-top portion is located axially inward from the second top portion.

7. The second crown portion extends radially and circumferentially, The stator for a rotating electric machine according to claim 5, wherein the portion of the first circumferential portion that is different from the first top portion is located axially inward from the second top portion.

8. The first circumferential portion further comprises a first inner non-vertical portion which is the portion between the first vertex portion and the fourth root portion, and a first outer non-vertical portion which is the portion between the first vertex portion and the first root portion. The second circumferential portion further comprises a second inner non-vertical portion which is the portion between the second vertex portion and the third root portion, and a second outer non-vertical portion which is the portion between the second vertex portion and the second root portion. The stator for a rotating electric machine according to claim 5, wherein the first outer non-top portion is located axially inward of the second top portion, and the first inner non-top portion is located axially outward of the second inner non-top portion.

9. The stator for a rotating electric machine according to any one of claims 1 to 4, wherein the first root portion is offset radially outward with respect to the second root portion.

10. The second circumferential portion further comprises a second outer non-vertical portion which is the portion between the second vertex portion and the second root portion. The stator for a rotating electric machine according to claim 9, wherein the second outer non-top portion does not overlap with the first circumferential portion when viewed in the axial direction over its entire length.

11. The first crown portion extends radially and circumferentially, The stator for a rotating electric machine according to claim 9, wherein the second top portion extends radially and circumferentially, and its circumferential length is shorter than that of the first top portion.

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