Stator

Abstract

In this stator, a coil unit is wave-wound sequentially in stages along a first direction side in a peripheral direction, from an end on a second direction side to an end on the first direction side in a radial direction and, with an orientation of the peripheral direction being changed from the first direction to the second direction by a second coil end unit, is wave-wound sequentially along the second direction side in the peripheral direction, from an end on the first direction side to an end on the second direction side in the radial direction, by wave-winding coil units connected to each other.

Description

[Technical Field]

[0001] The present invention relates to a stator. [Background technology]

[0002] A stator having a stator core with a plurality of slots is known in the art, and is described, for example, in International Publication No. 2022 / 071029.

[0003] The stator described in WO 2022 / 071029 includes a stator core having a plurality of slots and a coil portion attached to the stator core. The coil portion is configured by a conductor connector. The conductor connector has a plurality of straight portions passing through the slots and a bent portion provided on one axial side of the stator core. In the coil portion, two straight portions are connected to each other via the bent portion. Furthermore, in the stator described in WO 2022 / 071029, the straight portions of the coil portion are arranged in four layers aligned radially in each of the plurality of slots. That is, four straight portions aligned radially pass through one slot. The conductor connector then travels around the stator core such that the straight portions alternately pass through adjacent layers. Specifically, the conductor connecting body is configured to go around the stator core in a zigzag pattern in the circumferential direction so that the straight portion alternately passes through the innermost layer and the second innermost layer, and then switch the layer through which the straight portion passes midway, and go around the stator core in a zigzag pattern in the circumferential direction so that the straight portion alternately passes through the third innermost layer and the outermost layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2022 / 071029 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the stator described in International Publication No. 2022 / 071029, the two alternating layers are switched midway by connecting the second-innermost layer to the third-innermost layer, so that the conductor alternates between the innermost layer and the second-innermost layer, and then between the third-innermost layer and the outermost layer. Therefore, the conductor must cross over the conductor of another coil end portion at the point where the second-innermost layer connects to the third-innermost layer to switch between the two alternating layers. Therefore, the axial size of the stator core increases at the midpoint of the radial portion of the slot in the coil end portion. This increases the size of the stator, so it is desirable to reduce the size of the coil portion in the axial direction of the stator core.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a stator that allows the size of the coil portion in the axial direction of the stator core to be reduced. [Means for solving the problem]

[0007] In order to achieve the above object, a stator according to one aspect of the present invention includes a stator core including a plurality of slots extending in the axial direction, and a coil portion disposed in each of the plurality of slots and having a wave-wound conductor, the coil portion including: a plurality of slot-accommodated portions accommodated in each of the plurality of slots in a state of being lined up along the radial direction of the stator core; first coil end portions connecting pairs of slot-accommodated portions that are accommodated in different slots and have different radial positions; and second coil end portions connecting pairs of slot-accommodated portions that are accommodated in different slots and have the same radial position; and the first coil end portions are arranged in the slot-accommodated portions of the slot-accommodated portions that are accommodated in different slots and have the same radial position. By connecting pairs of the slot-housed portions together so that the radial position changes stepwise from the other end of the radial direction toward one side in the radial direction, a wave-wound coil section is formed around the stator core together with the slot-housed portions, and by connecting pairs of the slot-housed portions together, the second coil end portions connect at least one pair of wave-wound coil sections that are wave-wound stepwise in sequence, such that the coil section is wave-wound stepwise from the other end of the radial direction along one side in the circumferential direction by the wave-wound coil sections connected to each other, and the second coil end portions change the circumferential direction from one end to the other in the radial direction along the other side in the circumferential direction. Note that the term "connection" used here is used as a broad concept that includes not only connecting different conductor members by joining them but also connecting them as a single conductor.

[0008] In a stator according to one aspect of the present invention, as described above, the coil portions are wave-wound in stages along one circumferential side from the other radial end to the other radial end by the interconnected wave-wound coil portions, and the second coil end portions change the circumferential direction from one side to the other, and then wave-wound along the other circumferential side from the one radial end to the other radial end. This allows the slot-housed portions to be connected without a portion where the radial positions of the connected slot-housed portions change midway, such as when the second-innermost layer is connected to the third-innermost layer, unlike a case where adjacent slot-housed portions are alternately connected in each of the slots, such as when the second-innermost layer is connected to the third-innermost layer. Therefore, the slot-housed portions can be connected without a portion where the connecting portion crosses over another coil portion midway through the radial slot. As a result, the size of the coil portions in the axial direction of the stator core can be reduced.

[0009] In the stator according to the above aspect, preferably, the first coil end portion forming one of the wave-wound coil sections connected to each other and the first coil end portion forming the other of the wave-wound coil sections are connected in pairs of slot-accommodated portions such that the radial positions of the connecting slot-accommodated portions are changed stepwise in parallel to each other.

[0010] With this configuration, the radial positions of the connected slot-accommodated portions of the two connected wave winding coil sections are changed in stages parallel to each other, so that the shapes of the conductors constituting the two connected wave winding coil sections can be made common. Therefore, even when the connected wave winding coil sections are connected in a folded-back manner, an increase in the number of different shapes of the conductor member can be suppressed, and therefore the number of different conductor members used to form the coil sections can be suppressed.

[0011] In the stator according to the above aspect, preferably, the second coil end portion includes both an outermost coil end portion connecting the slot-accommodated portions located radially outermost in each of the plurality of slots, and an innermost coil end portion connecting the slot-accommodated portions located radially innermost, and a plurality of wave-wound coil portions are provided, and the plurality of wave-wound coil portions, the outermost coil end portion and the innermost coil end portion form a wave-wound coil portion in which the winding direction in the circumferential direction is changed multiple times.

[0012] With this configuration, the multiple wave-wound coil portions and the outermost and innermost coil end portions form a wave-wound coil portion in which the winding direction in the circumferential direction is changed multiple times, so that the coil portion can be configured so that the winding direction in the circumferential direction is changed multiple times at each of the innermost and outermost radial portions of the slot. Therefore, even when a large number of slot-received portions are accommodated in one slot, the coil portion can be configured by folding back multiple times at each of the innermost and outermost radial portions of the slot, so that the size of the coil portion in the axial direction of the stator core can be reduced.

[0013] In the stator according to the above aspect, the first coil end portion preferably connects pairs of slot-accommodated portions that are arranged in different slots and are shifted radially outward or inward from each other.

[0014] With this configuration, the coil portion can be formed by connecting pairs of slot-received portions that are offset radially outward or inward, thereby enabling the slot-received portions to be densely arranged in each of the multiple slots. Therefore, the multiple slot-received portions arranged in the slots can be efficiently connected, and the radial positions of the connected slot-received portions can be changed stepwise toward one radial side.

[0015] In the stator according to the above aspect, preferably, the slot-received portion forming one of the wave-wound coil portions connected to each other and the slot-received portion forming the other of the wave-wound coil portions are arranged in adjacent slots.

[0016] Here, if the slot-received portions of both of the mutually connected wave winding coil sections are arranged in a common slot, the positional relationship of the coil sections with respect to the magnets arranged in the rotor facing the stator will be biased, causing bias in the current flowing through the wave winding coil sections. In consideration of this point, in the present invention, the slot-received portion forming one of the mutually connected wave winding coil sections and the slot-received portion forming the other of the wave winding coil sections are arranged in adjacent slots, thereby making it possible to prevent bias in the current flowing through the wave winding coil sections.

[0017] In the present application, the stator according to the above aspect may also have the following configuration.

[0018] (Additional note 1) In a configuration in which the slot-accommodated portion forming one of the mutually connected wave-wound coil sections and the slot-accommodated portion forming the other are respectively arranged in adjacent slots, preferably, a wave-wound coil section is formed by changing the winding direction in the circumferential direction multiple times using a plurality of wave-wound coil sections and a plurality of second coil end sections, and the slot-accommodated portions forming the coil sections are arranged alternately in pairs of adjacent slots.

[0019] With this configuration, even when the winding direction in the circumferential direction is changed multiple times to form a wave-wound coil section, the slot-accommodated portions that form the coil section can be arranged alternately in pairs of adjacent slots, thereby preventing imbalances in the current flowing through the coil section.

[0020] (Additional note 2) In the stator according to the above aspect, preferably, the coil portions include a U-phase coil portion, a V-phase coil portion, and a W-phase coil portion through which each of the three-phase AC currents flows, and each of the U-phase coil portion, V-phase coil portion, and W-phase coil portion has a wave-wound coil portion formed by the first coil end portion and the slot-accommodated portion, whereby pairs of slot-accommodated portions are connected by first coil end portions so that the radial position of the slot-accommodated portion is changed in stages toward one radial side, and one and the other of the wave-wound coil portions connected to each other are connected by second coil end portions so that the winding direction in the circumferential direction is changed.

[0021] With this configuration, even when forming coil sections through which the U phase, V phase, and W phase each flow, the coil sections for the U phase, V phase, and W phase are formed so that the radial position of the slot-accommodated portion is changed in stages toward one radial side, thereby making it possible to reduce the size of the coil sections in the axial direction of the stator core when forming the coil sections for the U phase, V phase, and W phase. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a plan view of a rotating electric machine (stator) according to an embodiment; [Figure 2] FIG. 2 is a circuit diagram of a Y-connected three-phase coil unit according to one embodiment. [Figure 3] FIG. 2 is a perspective view of a stator according to one embodiment. [Figure 4]4 is a diagram showing the configuration of a first coil portion of a U-phase coil portion. FIG. [Figure 5] 10 is a diagram showing the configuration of a second coil portion of the U-phase coil portion. FIG. [Figure 6] 10 is a diagram showing the configuration of a third coil portion of the U-phase coil portion. FIG. [Figure 7] 10 is a diagram showing the configuration of a fourth coil portion of the U-phase coil portion. FIG. [Figure 8] FIG. 10 is a diagram for explaining a portion connecting slot-accommodated portions of the first turn on the outermost radial side in the radial direction. [Figure 9] FIG. 10 is a diagram for explaining a portion connecting slot-accommodated portions of eighth turns on the innermost radial side in the radial direction. [Figure 10] 4A and 4B are diagrams illustrating the configuration of a conductor member that constitutes a coil portion. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] The structure of a rotating electrical machine 200 including a stator 100 according to this embodiment will be described with reference to FIGS.

[0025] In this specification, the term "axial direction" refers to the direction (Z direction: see FIG. 1) along the rotation axis (symbol O) of the stator core 10 (rotor 150). One side of the axial direction is referred to as the Z1 direction, and the other side as the Z2 direction. The term "circumferential direction" refers to the circumferential direction (A direction) of the stator core 10. One side of the circumferential direction is referred to as the A1 direction, and the other side as the A2 direction. The term "radial direction" refers to the radial direction (B direction) based on the rotation axis of the stator core 10 (rotor 150). The terms "radially inner" and "inner diameter side" refer to the direction toward the center of the stator core 10 (B1 direction). The terms "radially outer" and "outer diameter side" refer to the direction toward the outside of the stator core 10 (B2 direction).

[0026] As shown in FIG. 1, the rotating electric machine 200 includes a stator 100 and a rotor 150. The stator 100 and the rotor 150 are each formed in an annular shape. The stator 100 and the rotor 150 face each other. The rotor 150 is disposed radially inward (on the B1 direction side) of the stator 100. The rotor 150 is provided with a plurality of permanent magnets (not shown). That is, the rotating electric machine 200 of this embodiment is configured as an inner rotor type rotating electric machine.

[0027] (Stator configuration) The stator 100 includes a stator core 10. The stator core 10 is disposed radially opposite the rotor 150. The stator core 10 is provided with a plurality of (for example, 48) slots 11. Teeth 12 are provided between adjacent slots 11. The stator core 10 is formed, for example, by stacking a plurality of electromagnetic steel plates in the direction of the rotation center axis (Z1 direction and Z2 direction), and is configured to allow magnetic flux to pass through. The stator core 10 has end faces 10a on both one side (Z1 direction side) and the other side (Z2 direction side) in the axial direction. The stator 100 also includes a coil section 20.

[0028] 2, the coil section 20 is connected to an external power supply and configured to receive power (e.g., three-phase AC power). The coil section 20 is configured to generate a magnetic field when power is supplied. The coil section 20 includes a U-phase coil section 30, a V-phase coil section 40, and a W-phase coil section 50, through which three-phase (U-phase, V-phase, and W-phase) AC currents flow, respectively.

[0029] The U-phase coil section 30 includes a first coil section 31, a second coil section 32, a third coil section 33, and a fourth coil section 34 of the U phase, which are connected in parallel to one another. The V-phase coil section 40 includes a first coil section 41, a second coil section 42, a third coil section 43, and a fourth coil section 44 of the V phase, which are connected in parallel to one another. The W-phase coil section 50 includes a first coil section 51, a second coil section 52, a third coil section 53, and a fourth coil section 54 of the W phase, which are connected in parallel to one another. The U-phase coil section 30, the V-phase coil section 40, and the W-phase coil section 50 are connected in Y-connection (star connection). That is, AC power for the U phase, the V phase, and the W phase is input from a power line 61 to the U-phase coil section 30, the V-phase coil section 40, and the W-phase coil section 50, respectively. The output sides of the U-phase coil section 30, the V-phase coil section 40, and the W-phase coil section 50 are connected to one another via a neutral conductor 62.

[0030] As shown in Fig. 3, the coil portion 20 is disposed in each of the plurality of slots 11, and the conductor is wave-wound. Specifically, the coil portion 20 includes a slot-received portion 21 and a coil end portion 22. The slot-received portion 21 is received in each of the plurality of slots 11 formed to extend in the axial direction (Z direction). The coil end portion 22 connects the plurality of slot-received portions 21 together in pairs. Specifically, the coil end portion 22 connects the slot-received portions 21 received in different slots 11 together. That is, when the coil portion 20 is disposed in the stator core 10, the coil portion 20 is disposed in one slot 11 in a portion corresponding to one slot-received portion 21, extending from one axial side to the other (from the Z1 direction to the Z2 direction) in the axial direction. Then, in a portion corresponding to a coil end portion 22 on the Z2 direction side, the coil portion 20 extends along the end face 10a of the stator core 10 on the Z2 direction side of the stator core 10, and then, in a portion corresponding to another slot-received portion 21, the coil portion 20 is disposed in another slot 11, extending from the other axial side to the one axial side (from the Z2 direction to the Z1 direction). Similarly, on the Z1 direction side, the coil portion 20 extends from the slot-received portion 21 along the end face 10a, and is further connected to the slot-received portion 21 at another different slot 11. The coil portion 20 is formed by wave-winding a conductor member 70 (see FIG. 10 ), which is a rectangular conductor wire.

[0031] In the coil section 20, the U-phase coil section 30, the V-phase coil section 40, and the W-phase coil section 50 have the same configuration. Therefore, the U-phase coil section 30 will be described below.

[0032] The U-phase coil section 30 is arranged on the stator core 10 in a state where a first coil section 31, a second coil section 32, a third coil section 33, and a fourth coil section 34, which are connected in parallel to one another, are combined in a cage shape. One end of each of the first coil section 31, the second coil section 32, the third coil section 33, and the fourth coil section 34 is connected to a power line 61. Alternating current power is supplied from the power line 61. The other end of each of the first coil section 31, the second coil section 32, the third coil section 33, and the fourth coil section 34 is connected to a neutral line 62.

[0033] As shown in Figures 4 to 7, the first coil section 31, second coil section 32, third coil section 33, and fourth coil section 34 of the U-phase coil section 30 are each arranged in slots 11 #1 (hereinafter, "number" will be written as "#"), #6, #7, #12, #13, #18, #19, #24, #25, #30, #31, #36, #37, #42, #43, and #48 out of the 48 slots 11. Here, slots 11 of #1 and #48, slots 11 of #6 and #7, slots 11 of #12 and #13, slots 11 of #18 and #19, slots 11 of #24 and #25, slots 11 of #30 and #31, slots 11 of #36 and #37, and slots 11 of #42 and #43 are each two slots 11 adjacent to each other in the circumferential direction (direction A). Note that FIGS. 4 to 7 are views showing the annular stator core 10 cut open, with the up-down direction being the radial direction (direction B) of the stator core 10 and the left-right direction being the circumferential direction (direction A) of the stator core 10. That is, in FIGS. 4 to 7, the left and right ends of the drawings are connected to each other. Although not shown, the V-phase coil portion 40 and the W-phase coil portion 50 are arranged in the stator core 10 so as to be offset from the U-phase coil portion 30 by two slots 11 and four slots 11, respectively.

[0034] The multiple slot-accommodated portions 21 are accommodated in each of the multiple slots 11, lined up along the radial direction (direction B) of the stator core 10. Specifically, in this embodiment, eight slot-accommodated portions 21 are arranged in a row in the radial direction in one slot 11. For example, in one slot 11, the slot-accommodated portion 21 arranged on the outermost side (outer diameter side: B2 direction side) is the first turn (first layer), and the slot-accommodated portion 21 arranged on the innermost side (inner diameter side: B1 side) is the eighth turn (eighth layer). Note that in FIGS. 4 to 7, the slot-accommodated portions 21 are arranged so that current flows in the order of the white numbers at positions indicated by white numbers on a black background.

[0035] In this embodiment, coil end portion 22 has portion 23, portion 24, and portion 25. In FIGS. 4 to 7, coil end portion 22 (portion 23, portion 24, and portion 25) shown by solid lines are located on the Z1 direction side of stator core 10, and coil end portion 22 (portion 23) shown by dashed lines is located on the Z2 direction side of stator core 10. Note that portion 23 is an example of a "first coil end portion" in the claims. Furthermore, portion 24 is an example of a "second coil end portion" and an "outermost coil end portion" in the claims. Furthermore, portion 25 is an example of a "second coil end portion" and an "innermost coil end portion" in the claims. Furthermore, in Figures 4 to 7, coil end portions 22 (portions 23, 24, and 25) are schematically illustrated as straight lines when viewed from the Z direction, but coil end portions 22 (portions 23, 24, and 25) may have a curved shape when viewed from the Z direction.

[0036] The portions 23 connect pairs of slot-housed portions 21 that are located at different radial positions (direction B) among the multiple slot-housed portions 21 housed in different slots 11. Specifically, the portions 23 connect the slot-housed portions 21 so that the radial positions (number of turns) of the connected slot-housed portions 21 change stepwise sequentially toward one radial side. That is, the portions 23 connect pairs of slot-housed portions 21 so that the number of turns increases toward one circumferential side (direction A1). In the coil portion 20, the portions 23 and the slot-housed portions 21 form four wave-wound coil portions 20a, 20b, 20c, and 20d that are wave-wound around the stator core 10 along a common circumferential direction.

[0037] In this embodiment, in each of the wave-wound coil sections 20a to 20d, the plurality of portions 23 are connected to the slot-received portions 21, thereby connecting the slot-received portions 21 arranged in order from the slot-received portion 21 arranged on the outermost radial side (first turn) to the slot-received portion 21 arranged on the innermost radial side (eighth turn). That is, the plurality of portions 23 connect the slot-received portions 21 in pairs so that the radial positions of the connected slot-received portions 21 change stepwise from the slot-received portion 21 arranged at the first turn position, which is the end on the other radial side (for example, the B2 side) of the slot 11, to the slot-received portion 21 arranged at the eighth turn position, which is the end on one side (for example, the B1 side). In this embodiment, the portions 23 connect pairs of the slot-received portions 21 arranged in different slots 11, which are shifted radially outward or inward by one. That is, in each of the wave winding coil portions 20a to 20d, the portions 23 connect the slot-accommodated portions 21 while being shifted by one turn in order from the eighth turn to the first turn.

[0038] The wave-wound coil portions 20a to 20d are arranged to make at least one round trip (two round trips in this embodiment). That is, the wave-wound coil portions 20a to 20d are arranged so that the current flows through them in the circumferential direction in at least one round trip (two round trips in this embodiment). In other words, the four wave-wound coil portions 20a to 20d change the circumferential direction of the current flowing through the coil portion 20 (the winding direction in the circumferential direction) at least once (three times in this embodiment). Each wave-wound coil portion 20a is wave-wound in stages by the slot-accommodated portion 21 and the portion 23 along one circumferential side toward one radial side (direction B1) so that the current flows toward one circumferential side of the stator core 10 (for example, direction A1). The wave-wound coil section 20b connected to the wave-wound coil section 20a is wave-wound in stages along the other circumferential side toward the other radial side (direction B2) so that current flows toward the other circumferential side (for example, direction A2) opposite to the wave-wound coil section 20a. The wave-wound coil section 20c and the wave-wound coil section 20d are similarly wave-wound so that current flows toward one circumferential side and the other circumferential side, respectively. The wave-wound coil section 20a, the wave-wound coil section 20b, the wave-wound coil section 20c, and the wave-wound coil section 20d are connected in this order to form the first coil section 31, the second coil section 32, the third coil section 33, and the fourth coil section 34 of the U-phase coil section 30 in the coil section 20, respectively. That is, each of the first coil portion 31, the second coil portion 32, the third coil portion 33, and the fourth coil portion 34 is arranged on the stator core 10 while folding back (changing) its circumferential direction three times.

[0039] In this embodiment, the wave-wound coil sections 20a to 20d are connected to one another by either the portion 24 or the portion 25. Each of the portion 24 and the portion 25 connects pairs of slot-housed sections 21 that are located at the same radial position (number of turns) among the multiple slot-housed sections 21 housed in different slots 11. Each of the portion 24 and the portion 25 connects pairs of slot-housed sections 21 together, thereby connecting at least one pair of the wave-wound coil sections 20a to 20d that are wave-wound in stages from the other end to one end in the radial direction along a common circumferential direction. Therefore, the coil portion 20 is wave-wound in stages along one circumferential side from the end on the other radial side (e.g., the B2 side) to the end on one side (e.g., the B1 side) by the interconnected wave-wound coil portions 20a-20d, and the circumferential direction is changed from one side to the other (e.g., from the A1 side to the A2 side) by the portions 24 and 25, and the coil portion 20 is wave-wound in stages along the other circumferential side from the end on one radial side to the end on the other radial side. Specifically, the portion 24 connects the slot-received portions 21 located on the outermost radial side (first turn) in each of the plurality of slots 11. The portion 25 connects the slot-received portions 21 located on the innermost radial side (e.g., the eighth turn) in each of the plurality of slots 11. Then, by connecting pairs of slot-housed portions 21 together by portions 24 or portions 25, one and the other of the connected round trips of wave-wound coil portions 20a-20d formed by portions 23 and slot-housed portions 21 are connected in a folded-back manner (so that the winding direction in the circumferential direction is changed). For example, in the first coil portion 31, four wave-wound coil portions 20a-20d, one portion 24, and two portions 25 form one wave-wound conductor (winding) that is folded back multiple times (so that the winding direction in the circumferential direction is changed multiple times).

[0040] 4, in the first coil portion 31, the power line 61 is connected to the slot-housed portion 21 (the portion with the white numeral 1) located on the outermost diameter side (first turn) of the #37 slot 11. The slot-housed portion 21 extends in the Z2 direction along the slot 11, and then a portion 23 extends from #37 to #31 as the Z2-direction coil end portion 22. On the Z2 direction side of the stator core 10, the portion 23 is connected to the slot-housed portion 21 (the portion with the numeral 2) located in the second turn of the #31 slot 11, shifted inward from the outermost diameter side. Thereafter, the portion 23 is connected to the slot-housed portions 21 alternately on the Z1 direction side and the Z2 direction side in the order of the third turn of slot 11 #25, the fourth turn of slot 11 #19, and the fifth turn of slot 11 #13, and is connected up to the slot-housed portion 21 of the eighth turn (portion numbered 8) of slot 11 #43 while increasing the number of turns inward by one. In this way, a wave-wound coil portion 20a connected by eight slot-housed portions 21 and seven portions 23 is formed.

[0041] Then, a portion 25 is provided on the Z1 side of the stator core 10 so as to fold back (changing the circumferential direction of the winding) from the slot-accommodated portion 21 of the 8th turn of the #43 slot 11 (the portion marked with the white numeral 8) to the slot-accommodated portion 21 of the 8th turn of the #48 slot 11 (the portion marked with the numeral 9). After being folded back at portion 25, the direction is changed in the circumferential direction A2 from the #48 slot 11 where portion 9 is provided to the #42 slot 11, and a wave-wound coil portion 20b is formed in the same manner as the wave-wound coil portion 20a. Then, a portion 24 is provided on the Z1 side of the stator core 10 from the slot-accommodated portion 21 of the 1st turn of the #42 slot 11 (the portion marked with the numeral 16) to the slot-accommodated portion 21 of the 1st turn of the #1 slot 11 (the portion marked with the numeral 17). This causes the first coil portion 31 to fold back from the wave-wound coil portion 20b to the wave-wound coil portion 20c. Thereafter, the first coil portion 31 is similarly folded back at portion 25 from the wave wound coil portion 20c to the wave wound coil portion 20d. In this way, the four wave wound coil portions 20a to 20d folded back three times form one first coil portion 31. The wave wound coil portion 20d is connected to the neutral conductor 62 from the slot-accommodated portion 21 (portion numbered 32) of the first turn of slot 11 of #6.

[0042] That is, in portion 23 of coil end portion 22, the portions connecting the second and third turns, the fourth and fifth turns, and the sixth and seventh turns are arranged on the Z1 direction side. Also, portion 24 connecting the first turns and portion 25 connecting the eighth turns are all arranged on the Z1 direction side. Note that power line 61 and neutral line 62 are also connected on the Z1 direction side.

[0043] As shown in Figures 5 to 7, each of the second coil section 32, the third coil section 33, and the fourth coil section 34, like the first coil section 31, is configured as part of the coil section 20 that is wave-wound by folding back the four wave-wound coil sections 20a to 20d multiple times (the winding direction in the circumferential direction is changed multiple times).

[0044] In this embodiment, the portion 23 forming one of the wave-wound coil sections 20a to 20d (one of the wave-wound coil sections 20a to 20d connected to each other) and the portion 23 forming the other of the wave-wound coil sections 20a to 20d (the other of the wave-wound coil sections 20a to 20d connected to each other) are connected in pairs such that the radial positions of the connected slot-housed portions 21 change stepwise (in a sloped manner) in parallel to each other. In addition, the number of slots 11 spanned by the portion 23 is the same in each of the multiple wave-wound coil sections 20a to 20d. Specifically, the portion 23 connects the slot-housed portions 21 by spanning five slots 11 while connecting the slot-housed portions 21 by shifting them by one turn. In other words, the number of pitches of the portions 23 is "6" in each of the multiple wave-wound coil sections 20a to 20d. The portions 23 have a common pitch on one side (Z1 direction side) and the other side (Z2 direction side) of the stator core 10. Note that "parallel" here means that the radial positions of the slot-accommodated portions 21 connected to the portions 23 are parallel when they are arranged along the circumferential direction. In other words, this means that the positions of the slot-accommodated portions 21 are parallel when the annular stator core 10 is shown in a cut-open form as in Figures 4 to 7.

[0045] Note that there are two types of portions 24 and 25: a 5-pitch portion and a 7-pitch portion. For example, in the first coil portion 31 of FIG. 4, the portion 24 with a 7-pitch portion is provided between slots 42 and 1 of slot 11, and portions 25 with a 5-pitch portion are provided between slots 43 and 48 and between slots 7 and 12. In contrast, in the second coil portion 32 of FIG. 5, the portion 24 with a 5-pitch portion is provided between slots 43 and 48 of slot 11, and portions 25 with a 7-pitch portion are provided between slots 42 and 1 and between slots 6 and 13.

[0046] 8 and 9, the portions 24 or portions 25 connected to the slot-received portions 21 arranged in the slots 11 at the same radial position and having different pitch numbers are arranged so as to overlap each other when viewed in the axial direction (Z direction). The portions 24 or portions 25 with a larger pitch number are arranged above (in the Z1 direction) the portions 24 or portions 25 with a smaller pitch number. Specifically, the portions 24 and portions 25 with a pitch number of 7 are arranged so as to cover above the portions 24 and 25 with a pitch number of 5, respectively.

[0047] 4 to 7, the slot-received portions 21 forming one of the connected round trips of the plurality of wave-wound coil portions 20a to 20d (one of the connected wave-wound coil portions 20a to 20d) and the slot-received portions 21 forming the other of the connected round trips (the other of the connected wave-wound coil portions 20a to 20d) are respectively arranged in adjacent slots 11. The slot-received portions 21 forming the coil portions 20 that are folded back multiple times (wave-wound with the winding direction in the circumferential direction changed multiple times) are alternately arranged in pairs of adjacent slots 11. Specifically, the U-phase coil portion 30, the V-phase coil portion 40, and the W-phase coil portion 50 are alternately arranged in pairs of adjacent slots 11 along the radial direction.

[0048] For example, in the U-phase first coil portion 31 of Fig. 4, the slot-received portions 21 forming the wave-wound coil portions 20a to 20d are received in two circumferentially adjacent slots 11, i.e., #1 and #48, #6 and #7, #12 and #13, #18 and #19, #24 and #25, #30 and #31, #36 and #37, and #42 and #43. In adjacent (one full rotation) wave-wound coil portions 20a to 20d, the slot-received portions 21 are alternately arranged in different slots 11. The U-phase second coil portion 32, third coil portion 33, and fourth coil portion 34 of Figs. 5 to 7 are similar to the U-phase first coil portion 31. This makes it possible to prevent deviations in the positional relationship between the first coil section 31, the second coil section 32, the third coil section 33, and the fourth coil section 34 of the U phase and the permanent magnets (not shown) of the rotor 150.

[0049] (Conductor member structure) As shown in FIG. 10 , the coil portion 20 is formed as a wave-wound conductor by connecting a plurality of conductor members 70. Specifically, in the coil portion 20, the plurality of conductor members 70 are connected (joined) to form slot-accommodated portions 21 and coil end portions 22 (portions 23, 24, and 25). Each of the plurality of conductor members 70 has an inverted U shape. The conductor member 70 includes a pair of slot-accommodated portions 21 and coil end portions 22 that connect the pair of slot-accommodated portions 21 on one axial side (Z1 side) of the stator core 10. In the conductor member 70, the shape of the coil end portions 22 differs for each of portions 23, 24, and 25. In the stator 100, the conductor member 70 is arranged so that the slot accommodating portion 21 is accommodated in each of the slots 11, and then the coil end portion 22 on the Z2 direction side is bent outward in the circumferential direction and joined to the coil end portion 22 on the Z2 direction side of a different conductor member 70 by laser joining or the like.

[0050] In this embodiment, the coil section 20 is configured using seven types of conductor members 70. The coil section 20 uses three types of conductor members 70 that configure the pair of slot-received portions 21 and portion 23, two types of conductor members 70 that configure the pair of slot-received portions 21 and portion 24, and two types of conductor members 70 that configure the pair of slot-received portions 21 and portion 25. The three types of conductor members 70 that configure the pair of slot-received portions 21 and portion 23 are three types of conductor members 70 that, on the Z1 direction side, connect the second turn to the third turn of portion 23, the conductor member 70 that connects the fourth turn to the fifth turn, and the conductor member 70 that connects the sixth turn to the seventh turn. The two types of conductor members 70 that configure the pair of slot-received portions 21 and portion 24 and the two types of conductor members 70 that configure the pair of slot-received portions 21 and portion 25 each have two types of pitch numbers, 5 and 7.

[0051] (Effects of this embodiment) In this embodiment, the following effects can be obtained.

[0052] In this embodiment, as described above, the coil portion 20 is wave-wound in stages along one circumferential side from the other radial end to the other radial end by the interconnected wave-wound coil portions 20a-20d, and the portions 24 and 25 (second coil end portions) change the circumferential direction from one side to the other, and are wave-wound in stages along the other circumferential side from the one radial end to the other radial end. This differs from a case in which adjacent slot-housed portions 21 are alternately connected in the radial direction so that, in each of the multiple slots 11, the winding passes alternately through the innermost layer (turn) and the second-innermost layer, and then the third-innermost layer and the outermost layer. This allows the slot-housed portions 21 to be connected without a portion where the radial positions of the connected slot-housed portions 21 change midway, such as the portion connecting the second-innermost layer to the third-innermost layer. Therefore, the slot-housed portions 21 can be connected without a portion where the connecting portion straddles another coil portion 20 midway through the radial slot 11. As a result, the size of the coil portion 20 in the axial direction of the stator core 10 can be reduced.

[0053] Furthermore, since the wave winding coil sections 20a to 20d can be configured so that the slot-accommodated portions 21 that are connected in stages from one radial end to the other radial end are arranged in each of the multiple slots 11, the ends of the wave winding coil sections 20a to 20d can be arranged at the innermost or outermost radial positions. Therefore, when connecting the power line 61, the neutral line 62, etc. to the coil section 20, the manufacturing process can be made less complicated than when connecting to a conductor (conductor member 70) midway through the slot 11.

[0054] Furthermore, when the winding direction in the circumferential direction is changed at a radially intermediate position in each of the multiple slots 11, the conductor must be arranged taking into account interference in both the axial and radial directions, which is likely to increase the size of the conductor in the axial direction. Additionally, when the portions whose winding direction is changed in the circumferential direction are arranged overlapping each other in the axial direction, the axial size increases due to interference considerations. In contrast, in this embodiment, the portions 24 and 25 (second coil end portions) connect the wave-wound coil portions 20a to 20d at the innermost or outermost radial positions, increasing the degree of freedom in their arrangement in the radial direction. Therefore, even when the portions 24 or the portions 25 are arranged overlapping each other in the axial direction at the innermost or outermost radial positions, the conductor size in the axial direction can be prevented from increasing compared to when the winding direction in the circumferential direction is changed at a radially intermediate position.

[0055] In the present embodiment, as described above, the connected wave winding coil sections 20a to 20d are arranged such that the radial positions of the connected slot-accommodated portions 21 change stepwise in parallel with each other, so that the shapes of the conductors (conductor members 70) constituting the connected wave winding coil sections 20a to 20d can be made the same. Therefore, even when the connected wave winding coil sections 20a to 20d are connected in a folded-back manner, an increase in the types of shapes of the conductor members 70 can be suppressed, and therefore an increase in the types of conductor members 70 for forming the coil section 20 can be suppressed.

[0056] In the present embodiment, as described above, the coil section 20 is formed by wave-wound coil sections 20a to 20d, section 24 (outermost coil end section), and section 25 (innermost coil end section), with the winding direction in the circumferential direction being changed multiple times, so that the coil section 20 can be configured so that the winding direction in the circumferential direction is changed multiple times at each of the innermost and outermost radial sections of the slot 11. Therefore, even when the number of slot-received sections 21 received in one slot 11 is large, the coil section 20 can be configured by folding back multiple times at each of the innermost and outermost radial sections of the slot 11, so that the size of the coil section 20 in the axial direction of the stator core 10 can be reduced.

[0057] In this embodiment, as described above, the coil portion 20 can be configured by connecting pairs of slot-received portions 21 that are arranged so as to be shifted radially outward or inward, one by one, to each other, and therefore the slot-received portions 21 can be densely arranged in each of the multiple slots 11. Therefore, while efficiently connecting to the multiple slot-received portions 21 arranged in the slots 11, the slot-received portions 21 can be connected in pairs to each other so that the radial positions of the connected slot-received portions 21 are changed stepwise in order toward one radial side.

[0058] Here, if the slot-housed portions 21 are arranged in the same slot 11 in both of the wave winding coil portions 20a to 20d that are connected to each other, the positional relationship of the coil portion 20 with respect to the magnets arranged in the rotor 150 that faces the stator 100 will be biased, causing bias in the currents flowing through the wave winding coil portions 20a to 20d. In consideration of this point, in this embodiment, as described above, the slot-housed portions 21 that form one of the wave winding coil portions 20a to 20d that are connected to each other and the slot-housed portions 21 that form the other are arranged in adjacent slots 11, thereby making it possible to prevent bias in the currents flowing through the wave winding coil portions 20a to 20d.

[0059] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0060] For example, in the above embodiment, an example was shown in which the radial positions of the connected slot-accommodated portions 21 of the portion 23 (first coil end portion) forming one of the round trips of the wave-wound coil portions 20a to 20d and the portion 23 forming the other are changed in stages in parallel to each other, but the present invention is not limited to this. In the present invention, the radial positions of the slot-accommodated portions of one and the other of the round trips do not have to be parallel to each other.

[0061] Furthermore, in the above embodiment, an example was shown in which the coil portion 20 is formed by folding back three times using four wave-wound coil portions 20a to 20d, but the present invention is not limited to this. In the present invention, the coil portion may be configured so that it is folded back only once using two wave-wound coil portions. In this case, a second coil end portion that changes the winding direction in the circumferential direction may be arranged at the radially inner end as one radial side, or a second coil end portion that changes the winding direction in the circumferential direction may be arranged at the radially outer end. In other words, the second coil end portion may be either the innermost coil end portion or the outermost coil end portion. Furthermore, the one circumferential side and the other circumferential side may be oriented in the opposite direction to the example of the stator in the above embodiment.

[0062] Furthermore, in the above embodiment, an example was shown in which portion 23 (first coil end portion) connects pairs of slot-housed portions 21 that are arranged in different slots 11 and are offset from each other by one turn in the radial direction, but the present invention is not limited to this. In the present invention, the first coil end portion may also connect slot-housed portions that are offset by two or more turns. In other words, it may also connect slot-housed portions that are offset from each other by two or more turns.

[0063] In the above embodiment, the slot-received portion 21 forming one of the wave-wound coil portions 20a to 20d and the slot-received portion 21 forming the other of the wave-wound coil portions 20a to 20d are respectively arranged in adjacent slots 11, but the present invention is not limited to this. In the present invention, the slot-received portion forming one of the wave-wound coil portions for one round trip and the slot-received portion forming the other of the wave-wound coil portion for one round trip may be arranged in a common slot. Furthermore, the slot-received portion forming one of the wave-wound coil portions for one round trip and the slot-received portion forming the other of the wave-wound coil portion for one round trip may be arranged in slots spaced apart from each other.

[0064] Furthermore, although the above embodiment shows an example in which the coil portion 20 is formed by the inverted U-shaped conductor member 70, the present invention is not limited to this. In the present invention, after a rod-shaped conductor member is placed in the slot as a slot-receiving portion, a coil end portion may be formed by joining a conductor member separate from the rod-shaped conductor member. Also, the coil portion may be formed by combining an inverted U-shaped conductor member and a U-shaped conductor member from one axial side and the other axial side of the stator core. Also, the coil portion may be formed by a continuous wave-wound conductor.

[0065] In the above embodiment, an example has been shown in which the U-phase coil section 30, the V-phase coil section 40, and the W-phase coil section 50 each form a four-parallel coil, but the present invention is not limited to this. In the present invention, the U-phase coil section, the V-phase coil section, and the W-phase coil section do not have to be configured in parallel, and may instead be configured in two-parallel.

[0066] In addition, in the above embodiment, an example was shown in which 48 slots 11 are provided in the stator core 10 and each slot 11 accommodates eight slot accommodation portions 21 aligned radially, but the present invention is not limited to this. In the present invention, the number of slots in the stator core may be other than 48. Furthermore, the number of slot accommodation portions accommodated in one slot may also be other than eight.

[0067] [Summary of this embodiment] This embodiment has at least the following configuration.

[0068] The stator (100) comprises a stator core (10) including a plurality of slots (11) extending in the axial direction, and a coil section (20) arranged in each of the plurality of slots (11) and having a conductor wound in a wave pattern. The coil section (20) includes a plurality of slot-received portions (21) housed in each of the plurality of slots (11) in a state of being aligned along the radial direction of the stator core (10), first coil end portions (23) connecting pairs of the slot-received portions (21) that are located at different radial positions among the plurality of slot-received portions (21) housed in different slots (11), and second coil end portions (24, 25) connecting pairs of the slot-received portions (21) that are located at the same radial position among the plurality of slot-received portions (21) housed in different slots (11), and the first coil end portions (23) are arranged such that the radial positions of the slot-received portions (21) they connect are on one side of the radial direction. By connecting pairs of the slot-housed portions (21) together so that the radial direction changes stepwise from the other end to the one end toward the slot-housed portions (21), wave-wound coil sections (20a, 20b, 20c, 20d) are formed that are wave-wound around the stator core (10) in the circumferential direction together with the slot-housed portions (21), and the second coil end sections (24, 25) connect pairs of the slot-housed portions (21) together to connect at least pairs of wave-wound coil sections (20a, 20b, 20c, 20d) that are wave-wound stepwise in sequence in sequence, so that the coil section (20) is wave-wound stepwise in sequence from the other end in the radial direction along one side by the wave-wound coil sections (20a, 20b, 20c, 20d) that are connected to each other, and the second coil end sections (24, 25) change the circumferential direction from one side to the other, and are wave-wound stepwise in sequence from the one end in the radial direction along the other side in the circumferential direction.

[0069] With this configuration, unlike a case where radially adjacent slot-received portions 21 are alternately connected in each of the multiple slots 11, such as by alternately passing through the innermost layer and the second innermost layer, and then alternately passing through the third innermost layer and the outermost layer, the slot-received portions 21 can be connected without a portion where the radial position of the connected slot-received portions 21 changes midway, such as the portion where the second innermost layer is connected to the third innermost layer. Therefore, the slot-received portions 21 can be connected without a portion where the connection straddles another coil portion 20 midway through the radial slot 11. As a result, the size of the coil portion 20 in the axial direction of the stator core 10 can be reduced.

[0070] The first coil end portion (23) forming one of the wave-wound coil sections (20a, 20b, 20c, 20d) that are connected to each other and the first coil end portion (23) forming the other of the wave-wound coil sections (20a, 20b, 20c, 20d) connect the slot-accommodated portions (21) in pairs so that the radial positions of the connecting slot-accommodated portions (21) are changed stepwise in parallel with each other.

[0071] With this configuration, the radial positions of the connected slot-accommodated portions (21) of the connected wave-wound coil sections (20a, 20b, 20c, 20d) are arranged so as to change stepwise in parallel with each other, so that the shapes of the conductors constituting the connected wave-wound coil sections (20a, 20b, 20c, 20d) can be made common. Therefore, even when the connected wave-wound coil sections (20a, 20b, 20c, 20d) are connected in a folded-back manner, an increase in the number of types of conductor member shapes can be suppressed, and therefore the number of types of conductor members used to form the coil section (20) can be suppressed.

[0072] The second coil end portions (24, 25) include both an outermost coil end portion (24) that connects the slot-accommodated portions (21) that are located radially outermost in each of the multiple slots (11), and an innermost coil end portion (25) that connects the slot-accommodated portions (21) that are located radially innermost, and a plurality of wave-wound coil portions (20a, 20b, 20c, 20d) are provided, and the plurality of wave-wound coil portions (20a, 20b, 20c, 20d), the outermost coil end portions (24), and the innermost coil end portions (25) form a wave-wound coil portion (20) in which the winding direction in the circumferential direction is changed multiple times.

[0073] With this configuration, the coil section (20) is formed by wave-winding the winding direction in the circumferential direction by changing the winding direction multiple times using the plurality of wave-wound coil sections (20a, 20b, 20c, 20d) and the outermost and innermost coil end sections (24) and (25), so that the coil section (20) can be configured so that the winding direction in the circumferential direction is changed multiple times at each of the innermost and outermost radial sections of the slots (11). Therefore, even when a large number of slot-received sections (21) are received in one slot (11), the coil section (20) can be configured by folding back multiple times at each of the innermost and outermost radial sections of the slots (11), so that the size of the coil section (20) in the axial direction of the stator core (10) can be reduced.

[0074] The first coil end portion (23) connects pairs of slot-accommodated portions (21) arranged in different slots (11) that are arranged one radially outward or one radially inwardly.

[0075] With this configuration, the coil portion 20 can be configured by connecting pairs of slot-received portions 21 that are radially shifted outward or inward, respectively, so that the slot-received portions 21 can be densely arranged in each of the multiple slots 11. Therefore, the multiple slot-received portions 21 arranged in the slots 11 can be efficiently connected, and the slot-received portions 21 can be connected pairs such that the radial positions of the connected slot-received portions 21 are changed stepwise toward one radial side.

[0076] The slot-receiving portion (21) forming one of the wave-wound coil sections (20a, 20b, 20c, 20d) that are connected to each other and the slot-receiving portion (21) forming the other of the wave-wound coil sections (20a, 20b, 20c, 20d) are respectively arranged in adjacent slots (11).

[0077] Here, if the slot-housed portions 21 of both of the connected wave winding coil portions 20a, 20b, 20c, and 20d are arranged in the same slot 11, the positional relationship of the coil portion 20 with respect to the magnets arranged in the rotor 150 facing the stator 100 will be biased, resulting in biased currents flowing through the wave winding coil portions 20a, 20b, 20c, and 20d. In consideration of this, in this embodiment, the slot-housed portions 21 forming one of the connected wave winding coil portions 20a, 20b, 20c, and 20d and the slot-housed portions 21 forming the other of the connected wave winding coil portions 20a, 20b, 20c, and 20d are arranged in adjacent slots 11, thereby preventing biased currents flowing through the wave winding coil portions 20a, 20b, 20c, and 20d. [Explanation of symbols]

[0078] 10 stator core 11 slots 20 Coil section 20a, 20b, 20c, 20d Wave-wound coil section 21 Slot housing Part 23 (first coil end part) 24 section (second coil end section, outermost coil end section) 25 section (second coil end section, innermost coil end section) 100 Stator

Claims

1. a stator core including a plurality of axially extending slots; a coil portion disposed in each of the plurality of slots and having a conductor wound in a wave pattern; The coil portion a plurality of slot-accommodated portions that are accommodated in each of the plurality of slots and are aligned along the radial direction of the stator core; a first coil end portion connecting pairs of the slot-accommodated portions that are located at different radial positions among the plurality of slot-accommodated portions accommodated in the different slots; and second coil end portions connecting pairs of the slot-accommodated portions that are located at a common radial position among the plurality of slot-accommodated portions accommodated in different slots, the first coil end portion forms a wave-wound coil portion that is wave-wound around the stator core in a circumferential direction together with the slot-accommodated portions by connecting the slot-accommodated portions in pairs so that the radial positions of the connected slot-accommodated portions are changed stepwise from the end on the other side in the radial direction to the end on the one side toward the one side in the radial direction, the second coil end portions connect the slot-accommodated portions in pairs to each other, thereby connecting at least one pair of the wave-wound coil portions that are wave-wound in a sequential, stepwise manner, the coil portion is wave-wound in stages along one side of the circumferential direction from the end on the other side of the radial direction to the end on the one side by the wave-wound coil portions connected to each other, and the second coil end portion changes the circumferential direction from one side to the other, and the coil portion is wave-wound in stages along the other side of the circumferential direction from the end on one side of the radial direction to the end on the other side.

2. 2. The stator according to claim 1, wherein the first coil end portion forming one of the wave wound coil sections connected to each other and the first coil end portion forming the other of the wave wound coil sections connect the slot-accommodated portions in pairs such that the radial positions of the connected slot-accommodated portions are changed stepwise in parallel to each other.

3. the second coil end portion includes both an outermost coil end portion connecting the slot-accommodated portions that are arranged at the outermost positions in the radial direction in each of the plurality of slots, and an innermost coil end portion connecting the slot-accommodated portions that are arranged at the innermost positions in the radial direction, The wave winding coil portion is provided in plurality, 2. The stator according to claim 1, wherein the plurality of wave-wound coil portions, the outermost coil end portion, and the innermost coil end portion form the wave-wound coil portion in which the winding direction in the circumferential direction is changed multiple times.

4. 2. The stator according to claim 1, wherein the first coil end portions connect pairs of the slot-accommodated portions that are arranged in different slots and are shifted from each other by one outside or one inside in the radial direction.

5. 2. The stator according to claim 1, wherein the slot-accommodated portion forming one of the wave-wound coil sections connected to each other and the slot-accommodated portion forming the other of the wave-wound coil sections are respectively arranged in the slots adjacent to each other.

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