Rotating electric machines

Abstract

To provide a rotary electric machine exhibiting high cooling efficiency of a stator, with which manufacturing is easy.SOLUTION: A rotary electric machine 1 comprises a stator core in which a plurality of square conductors 8 are arranged inside a slot 7. The square conductors 8 comprise first coolant channels 21a formed mutually between normal shape parts 8N in a plurality of square conductors 8, and a second coolant channel 21b formed between specific shape parts 8S of the plurality of square conductors 8 and an inner wall of the slot 7 in such a manner that the specific shape parts 8S each whose thickness dimension in a thickness direction orthogonal to a longitudinal direction of itself is relatively thin in one direction (CW) and is relatively thick in the other direction (EW) are formed between the normal shape parts 8N that are not the specific shape parts 8S; and the plurality of specific shape parts 8S in the plurality of square conductors 8 are arranged side by side inside the slot 7 so as to be mutually adjacent to each other.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] The stator of a rotating electric machine generates heat due to copper loss and iron loss. For this reason, a cooling method is sometimes adopted in which a coolant is circulated inside the stator. One proposal for this method is to provide grooves in the conductor inside the slot in the longitudinal direction of the conductor, which function as a flow path for the coolant, and to directly cool the conductor with the coolant flowing through these grooves (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7139969 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the method disclosed in Patent Document 1, it is difficult to mold the conductor itself to provide grooves that function as flow paths for the coolant. Furthermore, even if grooves are provided, there is a concern that the flow of coolant around the conductor may not be sufficient to improve the cooling effect.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a rotating electric machine that is easy to manufacture and has a high stator cooling efficiency. [Means for solving the problem]

[0006] (1) A rotating electric machine (for example, a rotating electric machine 1 described later) according to the present disclosure is a rotating electric machine having a stator core (for example, a stator core 6 described later) in which a plurality of rectangular conductors (for example, a rectangular conductor 8 described later) are arranged in slots (for example, slots 7 described later), and the rectangular conductors have a thickness dimension in a direction perpendicular to their longitudinal direction that is relatively thin in one direction (for example, a CW direction) and relatively thick in another direction (for example, an EW direction described later). The flat square conductors are provided with a first coolant flow path (for example, the first coolant flow path 21a described later) formed between the normal shape portions that are not the specific shape portions (for example, the normal shape portion 8N described later), and the specific shape portions of the multiple flat square conductors are arranged side by side in the slot so that they are adjacent to each other, and a second coolant flow path (for example, the second coolant flow path 21b described later) formed between the specific shape portions of the multiple flat square conductors and the inner wall of the slot.

[0007] (2) A rotating electric machine according to (1) above, wherein the first coolant flow path is a coolant flow path formed between the normal shape portions by stacking the relatively thick portions (EW) of the specific shape portions adjacent to each other in the slot 7 in the stacking direction.

[0008] (3) A rotating electric machine according to (1) above, wherein the second coolant flow path 21b is a coolant flow path formed between the inner wall of the slot 7 and the specific shape portion 8S by stacking the relatively thin portions (CW) of the specific shape portions 8S adjacent to each other in the slot 7 in the stacking direction. [Effects of the Invention]

[0009] In the rotating electric machine (1) described above, the flat rectangular conductors are arranged in parallel within the slot so that their specific-shaped portions are adjacent to each other, forming a first coolant flow path between the regular-shaped portions of the flat rectangular conductors and a second coolant flow path between the specific-shaped portions of the flat rectangular conductors and the inner wall of the slot. Therefore, even if the insulating paper placed between the inner wall of the slot and the straight portions of the flat rectangular conductors contains a foam material, when the flat rectangular conductors are arranged within the slot, a first coolant flow path is established between each adjacent flat rectangular conductor, and a second coolant flow path is established between the inner wall of the slot (including insulating materials such as insulating paper) and each flat rectangular conductor, communicating with the first coolant flow path. The coolant flowing through these coolant flow paths efficiently cools the flat rectangular conductors during operation of the rotating electric machine (1).

[0010] In the rotating electric machine of (2) above, the first coolant flow path is a coolant flow path formed between the regular-shaped portions by connecting the relatively thick portions of the specific-shaped portions that are adjacent to each other and arranged side by side in the slot in the stacking direction. Therefore, a coolant flow path as the first coolant flow path is secured between the regular-shaped portions of the flat conductor, and the coolant flowing through this coolant flow path promotes cooling of the flat conductor.

[0011] In the rotating electric machine of (3) above, the second coolant flow path is a coolant flow path formed between the inner wall of the slot and the specific shaped portion by connecting the relatively thin portions of the specific shaped portions that are adjacent to each other and arranged side by side in the slot in the stacking direction. This ensures a coolant flow path as the second coolant flow path between the inner wall of the slot and the specific shaped portion of the rectangular conductor, and the coolant flowing through the second coolant flow path flows smoothly to the first coolant flow path, accelerating cooling of the entire rectangular conductor. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a conceptual diagram of a coolant circulation mechanism in a rotating electric machine according to an example of the present disclosure; [Figure 2]2 is a schematic diagram showing an example of a coolant flow path from a stator core to a stator coil in the rotating electric machine of FIG. 1. FIG. [Figure 3] 1. FIG. 4 is a schematic diagram showing another example of the coolant flow path from the stator core to the stator coil in the rotating electric machine of FIG. [Figure 4A] 2 is a diagram showing one step in an example of a method for manufacturing a rectangular conductor for a stator coil applied to the rotating electric machine of FIG. 1. FIG. [Figure 4B] 1. FIG. 4 is a diagram showing the next step in an example of a method for manufacturing a rectangular conductor for a stator coil applied to the rotating electric machine of FIG. [Figure 4C] 1. FIG. 4 is a diagram showing a further next step in an example of a method for manufacturing a rectangular conductor for a stator coil applied to the rotating electric machine of FIG. [Figure 5] 4 is a schematic diagram showing a coolant flow path within a circle IS in FIGS. 2 and 3. FIG. [Figure 6] 6 is a schematic diagram showing the coolant flow path of FIG. 5 in cross section along line AA. [Figure 7] 6 is a schematic diagram showing the coolant flow path in FIG. 5 in cross section along line BB. [Figure 8] FIG. 10 is a perspective view showing a stator of a rotating electric machine according to another example of the present disclosure. [Figure 9] 9 is a schematic diagram showing an example of a coolant flow path within a slot in the rotating electric machine of FIG. 8. FIG. [Figure 10] 10 is a schematic diagram showing a coolant flow path within a circle IS in FIG. 9. FIG. [Figure 11] 11 is a schematic diagram showing the coolant flow path of FIG. 10 in cross section along line AA. FIG. [Figure 12] 11 is a schematic cross-sectional view of the coolant flow path in FIG. 10 taken along line BB. [Figure 13] 10 is a diagram showing another example of a rectangular conductor arranged in the slot of the rotating electric machine of FIG. 1 and FIG. 8. FIG. [Figure 14] 10 is a diagram showing still another example of rectangular conductors arranged in slots of the rotating electric machine of FIG. 1 and FIG. 8. FIG. [Figure 15A] 10 is a diagram showing one step in another example of a method for manufacturing a rectangular conductor that is applied to the rotating electric machine of FIGS. 1 and 8. FIG. [Figure 15B] 10 is a diagram showing the next step in another example of a method for manufacturing a rectangular conductor applied to the rotating machine of FIG. 1 and FIG. 8. [Figure 15C] 10 is a diagram showing a further next step in another example of a method for manufacturing a rectangular conductor applied to the rotating electric machine of FIGS. 1 and 8. FIG. [Figure 16] FIG. 8 is a see-through perspective view showing an example of the configuration around the coolant flow path shown in FIGS. 5 to 7. [Figure 17] FIG. 17 is a conceptual diagram showing the coolant flow path portion extracted from FIG. 16. [Figure 18] FIG. 8 is a see-through perspective view showing another example of the configuration around the coolant flow path shown in FIGS. 5 to 7. [Figure 19] FIG. 19 is a conceptual diagram showing the coolant flow path portion extracted from FIG. 18. [Figure 20] FIG. 8 is a see-through perspective view showing still another example of the configuration around the coolant flow path shown in FIGS. 5 to 7. [Figure 21] FIG. 21 is a conceptual diagram showing the coolant flow path portion extracted from FIG. 20. DETAILED DESCRIPTION OF THE INVENTION

[0013] The rotating electric machine of the present disclosure will be described below with reference to the drawings. In each of the drawings shown below, corresponding parts are assigned the same reference numerals. In addition, in the drawings showing directions, AD represents the axial direction of the rotating electric machine, CD represents the circumferential direction of the rotating electric machine, and RD represents the radial direction of the rotating electric machine.

[0014] Fig. 1 is a conceptual diagram of a coolant circulation mechanism in a rotating electric machine 1 according to an example of the present disclosure. In Fig. 1, the rotating electric machine 1 includes a rotor 2 and a stator 3. The rotor 2 is cylindrical, and the stator 3, which has an annular cross section, is disposed around the rotor 2 with a predetermined gap therebetween.

[0015] A casing 4, which forms the outer shell of the rotating electric machine 1, is provided in contact with the outer periphery of the stator 3. A rotating shaft 5 passes through the center of rotation of the rotor 2 and is supported by bearings (not shown) at both axial end surfaces of the casing 4. A stator core 6 in the annular stator 3 has a plurality of slots 7 arranged at equal intervals along the circumferential direction. A plurality of rectangular conductors 8 are arranged in each of the slots 7. The rectangular conductors 8 (square conductors) with rectangular cross sections are electrically connected to form stator coils 9 arranged in the stator core 6. An insulating member 11 is arranged along the inner wall surface 10 of each of the slots 7. The insulating member 11 may be, for example, insulating paper with a foamed adhesive layer on one side and a non-foamed adhesive layer on the other side. The adhesive layer may be formed only in the relevant area.

[0016] The rotating electric machine 1 generates heat due to copper loss and iron loss, but the stator core 6 and stator coil 9 are cooled by coolant circulating through coolant flow paths 12 (described later) formed in the stator 3. Examples of the coolant include automatic transmission fluid (ATF). Coolant from a coolant reservoir 13 provided in the casing 4 is supplied to the suction side of a pump 15 through a filter 14. This coolant is cooled by heat exchange with coolant flowing through an external coolant flow path 17 in a heat exchanger 16 provided on the delivery side of the pump 15, and is then supplied to a coolant supply port 19 of the stator core 6 through a coolant supply path 18. The coolant supplied to the stator core 6 flows through a path (described later) while cooling the stator core 6 and the rectangular conductors 8 in the slots 7, before being collected in the coolant reservoir 13 and repeatedly recirculated.

[0017] Fig. 2 is a schematic diagram showing an example of the coolant flow path 12 extending from the stator core 6 to the stator coil 9 in the slot 7 in the rotating electric machine 1 of Fig. 1. Fig. 3 is a schematic diagram showing another example of the coolant flow path 12 extending from the stator core 6 to the stator coil 9 in the rotating electric machine 1 of Fig. 1. Referring to Fig. 2, the coolant flow path 12 is configured to extend from the casing 4 side of the stator 3 through an in-stator-core coolant flow path 20 provided in the stator core 6 to the stator coil 9 in the slot 7.

[0018] The coolant flow path 12 in Fig. 2 is configured so that the coolant supply port 19 of the casing 4 and the outer peripheral end of the slot 7 communicate with each other through an in-stator-core coolant flow path 20 provided in the stator core 6. The in-stator-core coolant flow path 20 of the coolant flow path 12 in Fig. 2 extends straight from the coolant supply port 19 of the casing 4 toward the inside in the radial direction to reach the outer peripheral end of the slot 7 and communicates with a first coolant flow path 21a, which will be described later. The first coolant flow path 21a communicates with a second coolant flow path 21b that runs along the longitudinal direction of the straight portion of the rectangular conductor 8.

[0019] On the other hand, the coolant flow passages 20 in the stator core of the coolant flow passage 12 in Fig. 3 extend axially from a coolant supply port 19 provided at a side end near the outer periphery of the stator core 6, turn radially inward at a midpoint in the thickness dimension of the stator core 6, reach the outer periphery side end of the slot 7, and communicate with first coolant flow passages 21a described below. The first coolant flow passages 21a communicate with second coolant flow passages 21b that run along the longitudinal direction of the straight portions of the rectangular conductors 8. The coolant flow passages 20 in the stator core in Fig. 3 communicate with a coolant circulation communication passage 21 formed in the circumferential direction (a direction intersecting the plane of Fig. 3) at a position midway toward the radially inward direction.

[0020] Here, the rectangular conductor 8 constituting the stator coil 9 will be described with reference to Figures 4A, 4B, and 4C. Figure 4A is a diagram showing one step in an example of a method for manufacturing the rectangular conductor 8 for the stator coil 9 applied to the rotating electric machine 1. Figure 4B is a diagram showing the next step in the example of a method for manufacturing the rectangular conductor 8. Figure 4C is a diagram showing the next step in the example of a method for manufacturing the rectangular conductor 8.

[0021] In this manufacturing method, a rectangular conductor 8 is first prepared, as shown in FIG. 4A. The rectangular conductor 8 in FIG. 4A is coated with an insulating coating, similar to other typical rectangular conductors of this type. Next, the rectangular conductor 8 is pressed with a press at the intermediate portion of the straight portion that will be placed in the slot 7 when it is formed into the stator coil 9. This pressurization causes the intermediate portion to be crushed and deformed, as shown in FIG. 4B. This results in a specific-shape portion 8S, where the thickness dimension in the direction perpendicular to the longitudinal direction of the rectangular conductor 8 is relatively thin in one direction (dimension CW in FIG. 4B) and relatively thick in the other direction (dimension EW in FIG. 4B). The inventors have verified that the insulating coating is not damaged when the rectangular conductor 8 is partially pressed and deformed with a press, as shown in FIG. 4B.

[0022] In this case, the flat rectangular conductor 8's normal-shaped portion 8N, not the specific-shaped portion 8S, is not crushed by the press and maintains its original shape, as shown in Figure 4A, i.e., its cross-sectional shape is rectangular and consistent throughout its entire length, with its original dimensions also remaining constant. In the next step, multiple flat rectangular conductors 8 formed as shown in Figure 4B are arranged in a row in the slot 7, as shown in Figure 4C, so that the positions of the specific-shaped portions 8S align with each other. The ends of the flat rectangular conductors 8 (normal-shaped portions 8N) arranged in this manner are electrically connected to each other, functioning as a stator coil 9. The flat rectangular conductor 8 does not have any special longitudinal grooves, making it easy to manufacture. Alternatively, a flat rectangular conductor 8 without an insulating coating can be prepared at the stage shown in Figure 4A. It can then be partially deformed by a press, as shown in Figure 4B, and an insulating coating applied (painted) to the portions other than the welding area.

[0023] As described above, by using a rectangular conductor 8 in which the specific shaped portions 8S are formed between the normal shaped portions 8N, a coolant flow path is formed around the stator coil 9. Next, the coolant flow path around the stator coil 9 will be described with reference to Figs. 5, 6 and 7.

[0024] FIG. 5 is a schematic diagram showing the coolant flow path within the circle IS in FIGS. 2 and 3. FIG. 6 is a schematic diagram showing the coolant flow path in FIG. 5 in a cross section taken along line AA. FIG. 7 is a schematic diagram showing the coolant flow path in FIG. 5 in a cross section taken along line BB. In FIG. 6, the specific-shaped portions 8S of the rectangular conductor 8 are radially overlapped within the slot 7 without any gaps. In FIG. 6, the relatively thicker portions of the specific-shaped portions 8S, which are the CW and EW portions shown in FIG. 4B, overlap radially within the slot 7. In this state, the gaps between both sides of the specific-shaped portions 8S of each rectangular conductor 8 (both sides of the relatively thin portions CW) and the inner wall of the slot 7 form second coolant flow paths 21b. As shown schematically on the right side of FIG. 6, the coolant CL flows through the second coolant flow path 21b from the radial outside to the radial inside.

[0025] On the other hand, in the portion shown in FIG. 7, the regular-shaped portions 8N of the rectangular conductor 8 are arranged radially within the slot 7, overlapping with gaps between them. In FIG. 7, the relatively thicker portions of the regular-shaped portions 8S (dimensions CW and EW in FIG. 4B) overlap as shown in FIG. 6, resulting in gaps between the regular-shaped portions 8N of the rectangular conductor 8 that are not the regular-shaped portions 8S. These gaps form the first coolant flow paths 21a. The area schematically surrounded by a dashed line on the right side of FIG. 7 is the first coolant flow path 21a. The coolant CL flows through the multiple first coolant flow paths 21a in the axial direction of the rotating electric machine 1.

[0026] Next, a rotating electric machine 1 according to another example of the present disclosure will be described with reference to Fig. 8. Fig. 8 is a perspective view showing a stator 3 of the rotating electric machine 1 according to another example of the present disclosure. A plurality of slots 7 are arranged circumferentially at equal intervals in a stator core 6 having an annular cross section in the rotating electric machine 1. A plurality of rectangular conductors 8 are arranged in each of the slots 7. The rectangular conductors 8 (square conductors) having a rectangular cross section are electrically connected at their ends to form a stator coil 9.

[0027] The rectangular conductors 8 are similar to those described with reference to Figures 4B and 4C. Annular front and rear cover members 22 and 23, which cover the front and rear ends of the stator coil 9, are attached to the axial front end (the near side in Figure 8) and the axial rear end (the far side in Figure 8) of the stator core 6. The front and rear cover members 22 and 23 accommodate the connecting conductor portions of the front and rear ends of the stator coil 9 and also form part of the flow path for the coolant CL. That is, the coolant CL introduced into the front cover member 22 circulates annularly within the front cover member 22, passes through the first coolant flow path 21a (partially the second coolant flow path 21b) formed between the rectangular conductors 8 in the slots 7, reaches the rear cover member 23, and then circulates through a coolant circulation path (not shown). This completes the coolant flow path 12.

[0028] FIG. 9 is a schematic diagram showing an example of a coolant flow path 12 in a slot 7 in the rotating electric machine 1 of FIG. 8. FIG. 10 is a schematic diagram showing a coolant flow path in a circle IS of FIG. 9. FIG. 11 is a schematic diagram showing the coolant flow path of FIG. 10 in a cross section taken along line AA. FIG. 12 is a schematic diagram showing the coolant flow path of FIG. 10 in a cross section taken along line BB. The coolant flow path 12 of FIG. 9 guides the coolant CL introduced into the front cover member 22 through first coolant flow paths 21a (partially, second coolant flow paths 21b between both sides of the flat conductors 8 and the inner walls of the slots 7) formed by gaps generated between the flat conductors 8 (normal-shaped portions 8N of the flat conductors 8) to the rear cover member 23 and back to a circulation path (not shown).

[0029] 10, 11, and 12, the formation of the first coolant flow path 21a and the second coolant flow path 21b and the flow pattern of the coolant CL in these first coolant flow path 21a and second coolant flow path 21b are substantially the same as those explained with reference to Figures 5, 6, and 7. Therefore, the same explanations regarding Figures 5, 6, and 7 will be used to explain the formation of the first coolant flow path 21a and the second coolant flow path 21b and the flow pattern of the coolant CL in these first coolant flow path 21a and second coolant flow path 21b in Figures 10, 11, and 12.

[0030] FIG. 13 shows another example of a rectangular conductor arranged in the slots of the rotating electric machine shown in FIGS. 1 and 8. The rectangular conductor 81 in the example shown in FIG. 13 has two specially shaped portions 81S on the linear portion arranged in the slot 7 of the rotating electric machine 1. Regularly shaped portions 81N are connected between these two specially shaped portions 81S and to both ends of the linear portion. The specially shaped portions 81S themselves are similar to the specially shaped portion 8S described above. The regularly shaped portions 81N themselves are similar to the regularly shaped portion 8N described above. By providing a rectangular conductor with two specially shaped portions 81S on its linear portion, two radial second coolant flow paths 21b can be formed in one slot 7. This reduces the overall flow tube resistance of the coolant CL and improves the energy efficiency of the rotating electric machine 1.

[0031] FIG. 14 shows another example of a rectangular conductor arranged in the slots of the rotating electric machine shown in FIGS. 1 and 8. The rectangular conductor 82 in the example shown in FIG. 14 has three specially shaped portions 82S along the straight portion arranged in the slot 7 of the rotating electric machine 1. Regularly shaped portions 82N are connected between these three specially shaped portions 82S and to both ends of the straight portion. The specially shaped portions 82S themselves are similar to the specially shaped portions 8S described above. The regularly shaped portions 82N themselves are similar to the regularly shaped portions 8N described above. By forming a rectangular conductor with three specially shaped portions 82S along its straight portion, it is possible to form three radial second coolant flow paths 21b in one slot 7. This reduces the overall flow tube resistance of the coolant CL and improves the energy efficiency of the rotating electric machine 1.

[0032] Here, another example of a method for manufacturing a rectangular conductor will be described with reference to Figures 15A, 15B, and 15C. Figure 15A is a diagram showing one step in another example of a method for manufacturing a rectangular conductor 8 applied to the rotating electric machine 1 of Figures 1 and 8. Figure 15B is a diagram showing the next step in another example of a method for manufacturing a rectangular conductor 8 applied to the rotating electric machine 1. Figure 15C is a diagram showing the next step in another example of a method for manufacturing a rectangular conductor 8 applied to the rotating electric machine 1 of Figures 1 and 8.

[0033] 15A, 15B, and 15C, first, a rectangular conductor 8 having a constant rectangular cross-sectional shape and constant dimensions over its entire length, as shown in Fig. 15A, is prepared. In this case, the rectangular conductor 8 is selected so that the ratio of the long side to the short side in the rectangular cross section is the EW to CW ratio of the specific shape portion 8S in Fig. 4B.

[0034] Next, the rectangular conductor 8 is pressed with a press on both end portions, excluding the intermediate portion (center position) of the straight portion placed in the slot 7. In Fig. 15B, the pressed portions are indicated by dashed circles PP. This pressing causes the end portions to be crushed and deformed, as shown in Fig. 15B, to have a rectangular cross section corresponding to the normal-shaped portion 8N in Fig. 4A.

[0035] The specific shape portion 8S, which is not the normal shape portion 8N of the flat rectangular conductor 8, is not crushed by the press and retains its original shape as shown in Figure 15A, i.e., its cross-sectional shape is constant and rectangular throughout its entire length, and the dimensional ratio of the short side to the long side of the rectangle also maintains the CW to EW ratio defined for the specific shape portion 8S in Figure 4B.

[0036] In the next step, a plurality of rectangular conductors 8 formed as shown in FIG. 15B are arranged in the slot 7 so that the positions of the specific-shaped portions 8S are aligned with each other, as shown in FIG. 15C. After this, the ends of the arranged rectangular conductors 8 (normal-shaped portions 8N) are connected by welding or other means to obtain the required electrical connection, and the conductors are ready to function as a stator coil 9. As described above, by using rectangular conductors 8 with specific-shaped portions 8S formed between the normal-shaped portions 8N, a coolant flow path is formed around the stator coil 9. The rectangular conductors 8 do not have any special grooves along their longitudinal direction, making them easy to manufacture.

[0037] Next, one embodiment of a flow path for the coolant CL in one slot 7 of the rotating electric machine 1 of the present disclosure will be generally outlined with reference to Figures 16 and 17. Figure 16 is a see-through perspective view showing an example of the configuration around the coolant flow path shown in Figures 5 to 7. Figure 17 is a conceptual diagram showing an extracted portion of the coolant flow path in Figure 16. As outlined with reference to Figure 1, the coolant CL is supplied from the outside to an axially intermediate position in the stator core 6 of the rotating electric machine 1.

[0038] The supplied coolant CL flows radially inward through second coolant flow paths 21b formed at three intermediate positions within the slot 7 as gaps between the inner wall of the slot 7 and the specific-shaped portions 8S of the rectangular conductors 8 radially stacked and aligned within the slot 7. In the example shown in Figs. 16 and 17, the second coolant flow paths 21b are provided at three positions: the central position in the axial direction of the slot 7 and two positions spaced from this central position on one end side and the other end side in the axial direction. More specifically, the second coolant flow paths 21b are formed as gaps between the outer surface of the rectangular conductor 8 and insulating paper serving as the insulating member 11 in close contact with the inner wall of the slot 7.

[0039] The coolant CL flowing through the second coolant flow path 21b flows through the first coolant flow path 21a, which is connected to the second coolant flow path 21b. The first coolant flow path 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the regular-shaped portions 8N of the rectangular conductor 8. The coolant CL flowing from the second coolant flow path 21b into the first coolant flow path 21a flows through the first coolant flow path 21a in the axial direction of the rotating electric machine 1.

[0040] The coolant CL branches from the second coolant flow path 21b at the axial center position to one axial end side and the other axial end side of the first coolant flow path 21a and flows. The coolant CL flowing through the second coolant flow path 21b and the first coolant flow path 21a flows through the slot 7 to one axial end side and the other axial end side while exchanging heat with the rectangular conductor 8 and cooling down heat generated by copper loss, and is discharged and drips from both axial ends of the slot 7, flows into the coolant reservoir 13 (see FIG. 1), and is collected as described above.

[0041] Next, with reference to Figures 18 and 19, an overview will be given of another aspect of the flow path of the coolant CL in one slot 7 of the rotating electric machine 1 of the present disclosure. Figure 18 is a see-through perspective view showing another example of the configuration around the coolant flow path shown in Figures 5 to 7. Figure 19 is a conceptual diagram showing an extracted portion of the coolant flow path in Figure 18. As outlined with reference to Figure 1, the coolant CL is supplied from the outside to an axially intermediate position in the stator core 6 of the rotating electric machine 1.

[0042] The supplied coolant CL flows radially inward through second coolant flow paths 21b formed at three intermediate positions within the slot 7 as gaps between the specific shaped portions 8S of each rectangular conductor 8 radially stacked and aligned within the slot 7 and the inner wall of the slot 7. More specifically, the second coolant flow paths 21b are formed as gaps between the outer surface of the rectangular conductor 8 and insulating paper serving as the insulating member 11 in close contact with the inner wall of the slot 7.

[0043] 18 and 19, the axial phase positions of the specially shaped portions 8S of each rectangular conductor 8 are gradually shifted in the axial direction from the outermost rectangular conductor 8 to the innermost rectangular conductor 8, moving radially inward. Therefore, the second coolant flow paths 21b formed within the slot 7 from the outer periphery to the inner periphery are inclined relative to the radial direction in accordance with the axial phase shift of the specially shaped portions 8S. These second coolant flow paths 21b are provided so as to be inclined from three positions toward the inner periphery: the central position in the axial direction at the outermost periphery of the slot 7, and two positions spaced from this central position on one axial end and the other axial end.

[0044] The coolant CL flowing through the second coolant flow path 21b flows through the first coolant flow path 21a, which is connected to the second coolant flow path 21b. The first coolant flow path 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the regular-shaped portions 8N of the rectangular conductor 8. The coolant CL flowing from the second coolant flow path 21b into the first coolant flow path 21a flows through the first coolant flow path 21a in the axial direction of the rotating electric machine 1.

[0045] The coolant CL branches from the second coolant flow path 21b at the axial center position to one axial end side and the other axial end side of the first coolant flow path 21a and flows. The coolant CL flowing through the second coolant flow path 21b and the first coolant flow path 21a flows through the slot 7 to one axial end side and the other axial end side while exchanging heat with the rectangular conductor 8 and cooling down heat generated by copper loss, and is discharged and drips from both axial ends of the slot 7, flows into the coolant reservoir 13 (see FIG. 1), and is collected as described above.

[0046] Next, with reference to Figures 20 and 21, an overview will be given of yet another aspect of the flow path of the coolant CL in one slot 7 of the rotating electric machine 1 of the present disclosure. Figure 20 is a see-through perspective view showing yet another example of the configuration around the coolant flow path shown in Figures 5 to 7. Figure 21 is a conceptual diagram showing an extracted portion of the coolant flow path in Figure 20. As outlined with reference to Figure 1, the coolant CL is supplied from the outside to an axially intermediate position in the stator core 6 of the rotating electric machine 1.

[0047] The supplied coolant CL flows radially inward through second coolant flow paths 21b formed at three intermediate positions within the slot 7 as gaps between the specific shaped portions 8S of each rectangular conductor 8 radially stacked and aligned within the slot 7 and the inner wall of the slot 7. More specifically, the second coolant flow paths 21b are formed as gaps between the outer surface of the rectangular conductor 8 and insulating paper serving as the insulating member 11 in close contact with the inner wall of the slot 7.

[0048] 20 and 21, the axial phase positions of the specially shaped portions 8S of each rectangular conductor 8 change in a zigzag pattern, shifting in one direction, then returning, and shifting again in the same direction as moving radially inward from the outermost rectangular conductor 8 to the innermost rectangular conductor 8. Therefore, the second coolant flow paths 21b formed within the slot 7 from the outer periphery to the inner periphery are zigzag in accordance with the axial phase shifts of the specially shaped portions 8S. These second coolant flow paths 21b are formed in a zigzag pattern from three locations toward the inner periphery: the axial center position at the outermost periphery of the slot 7, and two positions spaced from this center position on one axial end and the other axial end.

[0049] The coolant CL flowing through the second coolant flow path 21b flows through the first coolant flow path 21a, which is connected to the second coolant flow path 21b. The first coolant flow path 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the regular-shaped portions 8N of the rectangular conductor 8. The coolant CL flowing from the second coolant flow path 21b into the first coolant flow path 21a flows through the first coolant flow path 21a in the axial direction of the rotating electric machine 1.

[0050] The coolant CL branches from the second coolant flow path 21b at the axial center position to one axial end side and the other axial end side of the first coolant flow path 21a and flows. The coolant CL flowing through the second coolant flow path 21b and the first coolant flow path 21a flows through the slot 7 to one axial end side and the other axial end side while exchanging heat with the rectangular conductor 8 and cooling down heat generated by copper loss, and is discharged and drips from both axial ends of the slot 7, flows into the coolant reservoir 13 (see FIG. 1), and is collected as described above.

[0051] The rotating electric machine 1 in the present disclosure described above can be summarized as follows.

[0052] (1) The rotating electric machine 1 of the present disclosure is a rotating electric machine having a stator core 6 in which a plurality of flat rectangular conductors 8 are arranged in slots 7, and the flat rectangular conductors 8 have thickness dimensions in a direction perpendicular to their longitudinal direction that are relatively thin in one direction CW and relatively thick in the other direction EW, and these have specific shape portions 8S formed between normal shape portions 8N that are not specific shape portions 8S, and the specific shape portions of the plurality of flat rectangular conductors 8 are arranged in parallel in the slot so as to be adjacent to each other, and the rotating electric machine is provided with a first coolant flow path 21a formed between the normal shape portions 8N of the plurality of flat rectangular conductors 8, and a second coolant flow path 21b formed between the specific shape portions 8S of the plurality of flat rectangular conductors 8 and the inner wall of the slot 7.

[0053] In the rotating electric machine 1 described above in (1), multiple flat rectangular conductors 8 are arranged side by side in the slot so that their specific-shaped portions 8S are adjacent to each other. This forms first coolant flow paths 21a between the regular-shaped portions 8N of the multiple flat rectangular conductors 8 and second coolant flow paths 21b between the specific-shaped portions 8S of the multiple flat rectangular conductors 8 and the inner wall of the slot 7. Therefore, even if the insulating paper disposed between the inner wall of the slot 7 and the straight portions of the flat rectangular conductors 8 contains a foam material, when multiple flat rectangular conductors 8 are arranged in the slot 7, the first coolant flow paths 21a are formed between each adjacent flat rectangular conductor 8, and the second coolant flow paths 21b are formed between the inner wall of the slot (including the insulating member 11 such as insulating paper) and each flat rectangular conductor 8, communicating with the first coolant flow paths 21a. The coolant CL flowing through these coolant flow paths efficiently cools the flat rectangular conductors 8 during operation of the rotating electric machine 1.

[0054] (2) In one embodiment of the rotating electric machine 1 of the present disclosure, the first coolant flow path 21a is a coolant flow path formed between the normal shape portions 8N by stacking and arranging in the slot 7 the relatively thick portions (EW) of the specific shape portions 8S adjacent to each other in the stacking direction.

[0055] In the rotating electric machine 1 of the above aspect (2), the first coolant flow path 21a is a coolant flow path formed between the regular shaped portions 8N by connecting the relatively thick portions (EW) of the specific shaped portions 8S adjacent to each other in a juxtaposition in the slot 7 in the stacking direction. Therefore, a coolant flow path as the first coolant flow path 21a is secured between the regular shaped portions 8N of the rectangular conductor 8, and the coolant CL flowing through this coolant flow path promotes cooling of the rectangular conductor 8.

[0056] (3) In one embodiment of the rotating electric machine 1 of the present disclosure, the second coolant flow path 21b is a coolant flow path formed between the inner wall of the slot 7 and the specific shape portion 8S by connecting the relatively thin thickness portions (CW) of the specific shape portions 8S that are stacked and arranged in the slot 7 and adjacent to each other in the stacking direction.

[0057] In the rotating electric machine of (3) above, the second coolant flow path 21b is a coolant flow path formed between the inner wall of the slot and the shaped portion 8S by connecting the relatively thin portions (CW) of the adjacent shaped portions 8S arranged side by side in the slot 7 in the stacking direction. This ensures a coolant flow path as the second coolant flow path 21b between the inner wall of the slot and the shaped portion 8S of the rectangular conductor 8, and the coolant CL flowing through the second coolant flow path 21b flows smoothly to the first coolant flow path 21a, accelerating the cooling of the entire rectangular conductor 8.

[0058] While one embodiment of the rotating electric machine of the present disclosure has been described above, the technical concept of the present disclosure is not limited thereto. The detailed configuration may be modified as appropriate within the scope of the technical concept of the present disclosure. For example, instead of the specific shape portion 8S of the rectangular conductor 8 being rectangular, the relatively thick portion (EW) and the relatively thin portion (CW) may each be configured to have different three-dimensional shapes. [Explanation of symbols]

[0059] 1...Rotating electric machine 2...Rotor 3...Stator 4...Casing 5...Rotation axis 6... Stator core 7. Slot 8...Rectangular conductor 8N…Normal shape part 8S…Specific shape part 9...Stator coil 10...Inner wall surface 11...Insulating member 12…Cooling liquid flow path 13...Coolant reservoir 14...Filter 15...Pump 16...Heat exchanger 17…External coolant flow path 18…Cooling liquid supply path 19…Cooling liquid supply port 20...coolant flow path in stator core 21... Coolant circulation passage 21a...first coolant flow path 21b...Second coolant flow path 22...Front cover member 23...Rear cover member

Claims

1. A rotating electric machine having a stator core in which a plurality of rectangular conductors are arranged in slots, The flat rectangular conductor comprises a normal-shaped portion having a specific rectangular cross section and a specific-shaped portion having a thickness dimension in a direction perpendicular to its longitudinal direction that is relatively thinner than the normal-shaped portion in one direction and relatively thicker than the normal-shaped portion in another direction, and the specific-shaped portion is formed between the normal-shaped portions that are not the specific-shaped portions, A plurality of the flat rectangular conductors are arranged in the slot so that the specific shaped portions of the flat rectangular conductors are adjacent to each other, thereby forming a first coolant flow path between the normal shaped portions of the flat rectangular conductors; a second coolant flow path formed between the specific shaped portions of the plurality of flat rectangular conductors and the inner wall of the slot; A rotating electric machine equipped with the above.

2. 2. The rotating electric machine according to claim 1, wherein the first coolant flow path is a coolant flow path formed between the normal shape portions by stacking adjacent specific shape portions in the slot and connecting the relatively thick portions in the stacking direction.

3. 2. The rotating electric machine according to claim 1, wherein the second coolant flow path is a coolant flow path formed between the inner wall of the slot and the specific shaped portion by stacking the relatively thin portions of the specific shaped portions adjacent to each other in the slot in the stacking direction.

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