Rotary electric machine

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 method of circulating a coolant inside the stator to cool it is sometimes adopted. Regarding this method, there is a proposal to provide a groove that functions as a flow path for the coolant in the longitudinal direction of the conductor in the slot, and to directly cool the conductor with the coolant flowing through this groove (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, and even if grooves are provided, there is a concern that the flow of the coolant around the conductor may not be sufficient to improve the cooling effect.

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

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

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

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

[0009] In the rotating electric machine of (1) above, the flat square conductors are arranged in parallel in the slot so that the specific shaped portions are adjacent to each other, and a first coolant flow path is formed between the normal shaped portions of the flat square conductors, and a second coolant flow path is formed between the specific shaped portions of the flat square conductors and the inner wall of the slot. Therefore, even if the insulating paper arranged between the inner wall of the slot and the straight portion of the flat square conductor contains a foaming material, when the flat square conductors are arranged in the slot, a first coolant flow path is secured between each adjacent flat square conductor, and a second coolant flow path is secured between the inner wall of the slot (including insulating members such as insulating paper) and each flat square conductor, communicating with the first coolant flow path. The coolant flowing through these coolant flow paths can efficiently cool the flat square conductors when the rotating electric machine 1 is in operation.

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

[0011] In the rotating electric machine of (3) above, the second coolant flow passage is a coolant flow passage formed between the inner wall of the slot and the specific shaped portion by connecting the relatively thin portions of the specific shaped portions arranged side by side in the slot in the stacking direction. This ensures a coolant flow passage as the second coolant flow passage 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 passage flows smoothly to the first coolant flow passage, accelerating the cooling of the entire rectangular conductor. [Brief description 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. [Diagram 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. [Diagram 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 a 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. [Diagram 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 in FIG. 5 along the line AA. FIG. [Figure 7] 6 is a schematic diagram showing the coolant flow path in FIG. 5 in a cross section taken along line BB. [Figure 8] 11 is a perspective view showing a stator of a rotating electric machine according to another example of the present disclosure. FIG. [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. [Figure 11] 11 is a schematic diagram showing the coolant flow path in FIG. 10 in cross section along line AA. [Figure 12] 11 is a schematic diagram showing the coolant flow path in FIG. 10 in cross section 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 a rectangular conductor arranged in the slot of the rotating electric machine of FIG. 1 and FIG. 8. FIG. [Figure 15A] 9 is a diagram showing one step in another example of a method for producing a rectangular conductor 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. FIG. [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 FIG. 1 and FIG. 8. FIG. [Figure 16] FIG. 8 is a see-through perspective view showing an example of a configuration around the coolant flow path shown in FIGS. 5 to 7. [Figure 17] 17 is a conceptual diagram showing a portion of the coolant flow path in FIG. 16. FIG. [Figure 18] 8 is a see-through perspective view showing another example of the configuration around the coolant flow path shown in FIGS. 5 to 7. FIG. [Figure 19] 19 is a conceptual diagram showing a portion of the coolant flow path in FIG. 18. [Figure 20] 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. FIG. [Figure 21] 21 is a conceptual diagram showing a portion of the coolant flow path in FIG. 20. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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, the same reference numerals are used for corresponding parts. In addition, in the drawings showing directions, AD indicates the axial direction of the rotating electric machine, CD indicates the circumferential direction of the rotating electric machine, and RD indicates 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 is provided in contact with the outer periphery of the stator 3, forming the outer shell of the rotating electric machine 1. A rotating shaft 5 passes through the center of rotation of the rotor 2, and the rotating shaft 5 is supported by bearings (not shown) at both axial end surfaces of the casing 4. A plurality of slots 7 are arranged at equal intervals in the circumferential direction in a stator core 6 of the annular stator 3. A plurality of rectangular conductors 8 are arranged in each of the plurality of slots 7. The rectangular conductors (square conductors) 8, each having a rectangular cross section, are electrically connected to form a stator coil 9 arranged in the stator core 6. An insulating member 11 is arranged along an inner wall surface 10 of each of the plurality of slots 7. As the insulating member 11, for example, insulating paper having a foamed adhesive layer on one side and a non-foamed adhesive layer on the other side is used. The adhesive layer may be formed only in the relevant portion.

[0016] The rotating electric machine 1 generates heat due to copper loss and iron loss, but the stator core 6 and the stator coil 9 are cooled by the coolant circulating through the coolant flow passage 12 formed in the stator 3, which will be described later. For example, ATF (automatic transmission fluid) is used as the coolant. The coolant discharged from the coolant reservoir 13 provided in the casing 4 is supplied to the suction side of the pump 15 through a filter 14. This coolant is cooled by heat exchange with the coolant flowing through the external coolant flow passage 17 in the heat exchanger 16 provided on the delivery side of the pump 15, and is supplied to the coolant supply port 19 of the stator core 6 through the coolant supply passage 18. The coolant supplied to the stator core 6 flows through a route described later, cooling the stator core 6 and the rectangular conductors 8 in the slots 7, and is collected in the coolant reservoir 13, where it is repeatedly recirculated.

[0017] Fig. 2 is a schematic diagram showing one 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 such 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 in 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 described below. 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 passage 20 in the stator core in the coolant flow passage 12 in Fig. 3 extends in the axial direction from the coolant supply port 19 provided at the side end near the outer periphery of the stator core 6, turns radially inward at the middle position of the thickness dimension of the stator core 6, reaches the outer periphery side end of the slot 7, and communicates with a first coolant flow passage 21a described later. The first coolant flow passage 21a communicates with a second coolant flow passage 21b along the longitudinal direction of the straight portion of the rectangular conductor 8. The coolant flow passage 20 in the stator core in Fig. 3 communicates with a coolant circulation communication passage 21 formed in the circumferential direction (the direction intersecting the paper surface of Fig. 3) at a position midway toward the radial inside.

[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 further next step in the example of a method for manufacturing the rectangular conductor 8.

[0021] In this manufacturing method, first, a rectangular conductor 8 having a constant rectangular cross-sectional shape and constant dimensions over its entire length as shown in FIG. 4A is prepared. The rectangular conductor 8 in FIG. 4A is covered with an insulating coating, like other general rectangular conductors of this type. Next, the intermediate portion of the straight portion of the rectangular conductor 8 that will be placed in the slot 7 when it is formed into a stator coil 9 is pressed with a press. This pressing causes the intermediate portion to be crushed and deformed as shown in FIG. 4B, forming a specific shape portion 8S whose 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 even if the rectangular conductor 8 is partially pressed and deformed with a press as shown in FIG. 4B, no damage is caused to the insulating coating.

[0022] In this case, the normal shape portion 8N, which is not the specific shape portion 8S of the rectangular conductor 8, is not crushed by the press machine and maintains the original shape as shown in FIG. 4A, that is, the cross-sectional shape is rectangular and constant over the entire length, and the dimensions are also constant as before. In the next step, the rectangular conductors 8 formed as shown in FIG. 4B are arranged in a row in the slot 7 so that the positions of the specific shape portions 8S match each other, as shown in FIG. 4C. The ends of the rectangular conductors 8 (normal shape portions 8N) arranged in this way are made to have a predetermined electrical connection relationship and function as the stator coil 9. The rectangular conductors 8 do not have a special groove along the longitudinal direction, so they are easy to manufacture. As an alternative, at the stage of FIG. 4A, a rectangular conductor 8 without an insulating coating may be prepared, and after it is partially pressed and deformed by a press machine as shown in FIG. 4B, an insulating coating may be applied (painted) to the portions other than the portions to be welded.

[0023] As described above, by using the rectangular conductor 8 having the specific shaped portion 8S formed between the normal shaped portions 8N, the coolant flow path around the stator coil 9 is formed. 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 in the circle IS in FIG. 2 and FIG. 3. FIG. 6 is a schematic diagram showing the coolant flow path in FIG. 5 in the AA line cross section. FIG. 7 is a schematic diagram showing the coolant flow path in FIG. 5 in the BB line cross section. In the portion of FIG. 6, the specific shape portion 8S of the rectangular conductor 8 is arranged overlapping each other in the radial direction in the slot 7 without creating a gap between them. In FIG. 6, the portion of the specific shape portion 8S having the relatively thick dimension EW of the dimensions CW and EW in FIG. 4B overlaps in the radial direction in the slot 7. In this state, the gaps generated between both sides of the specific shape portion 8S of each rectangular conductor 8 (both sides of the portion having the relatively thin dimension CW) and the inner wall of the slot 7 constitute the second coolant flow path 21b. As shown typically on the right side of FIG. 6, the coolant CL flows through the second coolant flow path 21b from the radial outside to the inside.

[0025] On the other hand, in the portion of Fig. 7, the normal shape portions 8N of the rectangular conductor 8 are arranged radially in the slot 7 with gaps between them. In Fig. 7, the relatively thicker portion of the dimension EW between the dimension CW and the dimension EW in Fig. 4B in the specific shape portion 8S overlaps as shown in Fig. 6, resulting in a gap between the normal shape portions 8N of the rectangular conductor 8 that are not the specific shape portions 8S. This gap forms the first coolant flow path 21a. The area diagrammatically 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 a rotating electric machine 1 according to another example of the present disclosure. A plurality of slots 7 are arranged at equal intervals in the circumferential direction 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 plurality of slots 7. The rectangular conductors (square conductors) 8 having a rectangular cross section are electrically connected at their ends to form a stator coil 9.

[0027] The rectangular conductor 8 is the same as that described with reference to Fig. 4B and Fig. 4C. An annular front cover member 22 and a rear cover member 23 that cover the front and rear ends of the stator coil 9 are attached to the axial front end (the near side in Fig. 8) and the axial rear end (the far side in Fig. 8) of the stator core 6. The front cover member 22 and the rear cover member 23 accommodate the connecting conductor parts of the front and rear ends of the stator coil 9 inside, and form a part of the flow path of the coolant CL. That is, the coolant CL introduced into the front cover member 22 circulates in a circular shape inside 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 slot 7, and reaches the rear cover member 23, forming a coolant flow path 12 that circulates through a coolant circulation path not shown.

[0028] FIG. 9 is a schematic diagram showing an example of the coolant flow path 12 in the slot 7 in the rotating electric machine 1 in FIG. 8. FIG. 10 is a schematic diagram showing the coolant flow path in the circle IS in FIG. 9. FIG. 11 is a schematic diagram showing the coolant flow path in FIG. 10 in a cross section taken along line AA. FIG. 12 is a schematic diagram showing the coolant flow path in FIG. 10 in a cross section taken along line BB. The coolant flow path 12 in FIG. 9 guides the coolant CL introduced into the front cover member 22 through a first coolant flow path 21a (partially, a second coolant flow path 21b between both sides of the flat conductor 8 and the inner wall of the slot 7) formed by gaps generated between the flat conductors 8 (normal shape portions 8N of the flat conductors 8) to the rear cover member 23 side, and returns 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 the first coolant flow path 21a and the second coolant flow path 21b are substantially similar to those described with reference to Fig. 5, 6 and 7. Therefore, the same description with reference to Fig. 5, 6 and 7 is used to describe 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 the first coolant flow path 21a and the second coolant flow path 21b in Fig. 10, 11 and 12.

[0030] FIG. 13 is a diagram showing another example of a rectangular conductor arranged in the slots of the rotating electric machine of FIG. 1 and FIG. 8. The rectangular conductor 81 in the example of FIG. 13 has two specific shape portions 81S in a straight portion arranged in the slot 7 of the rotating electric machine 1. The normal shape portions 81N are connected between these two specific shape portions 81S and to both ends of the straight portion. The specific shape portion 81S itself is the same as the above-mentioned specific shape portion 8S. The normal shape portion 81N itself is the same as the above-mentioned normal shape portion 8N. In this way, by making the rectangular conductor have two specific shape portions 81S in its straight portion, it is possible to form two second coolant flow paths 21b in the radial direction in one slot 7. This makes it possible to reduce the overall flow tube resistance related to the coolant CL and improve the energy efficiency of the rotating electric machine 1.

[0031] FIG. 14 is a diagram showing yet another example of a rectangular conductor arranged in the slots of the rotating electric machine of FIG. 1 and FIG. 8. The rectangular conductor 82 in the example of FIG. 14 has three specific shape portions 82S in a straight portion arranged in the slot 7 of the rotating electric machine 1. The normal shape portions 82N are connected between these three specific shape portions 82S and to both ends of the straight portion. The specific shape portions 82S themselves are the same as the above-mentioned specific shape portion 8S. In addition, the normal shape portions 82N themselves are the same as the above-mentioned normal shape portion 8N. In this way, by forming the rectangular conductor in a form having three specific shape portions 82S in its straight portion, it is possible to form three radial second coolant flow paths 21b in one slot 7. This makes it possible to reduce the overall flow tube resistance related to the coolant CL and improve the energy efficiency of the rotating electric machine 1.

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

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

[0034] Next, both end portions of the rectangular conductor 8, excluding the intermediate portion (center position) of the straight portion to be placed in the slot 7, are pressed by a press. In Fig. 15B, the portions to be pressed are indicated by the dashed circle PP. By this pressing, as shown in Fig. 15B, the both end portions are crushed and deformed, and become rectangular in 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 rectangular conductor 8, is not crushed by the press and retains its original form 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 match 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 the like to obtain a predetermined electrical connection relationship, and are made to function as a stator coil 9. As described above, a coolant flow path is formed around the stator coil 9 by using a rectangular conductor 8 in which the specific shaped portions 8S are formed between the normal shaped portions 8N. The rectangular conductor 8 does not have any special grooves along the longitudinal direction, and is therefore easy to manufacture.

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

[0038] The supplied coolant CL flows radially inward through the second coolant flow paths 21b formed at three intermediate positions in the slot 7 as gaps between the specific shaped portions 8S of the rectangular conductors 8 radially stacked and aligned in the slot 7 and the inner wall of the slot 7. In the example of Fig. 16 and Fig. 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 the central position on one end side and the other end side in the axial direction. In more detail, the second coolant flow paths 21b are formed as gaps between the insulating paper as the insulating member 11 in close contact with the inner wall of the slot 7 and the outer surface of the rectangular conductor 8.

[0039] The coolant CL flowing through the second coolant flow passage 21b flows through the first coolant flow passage 21a that communicates with the second coolant flow passage 21b. The first coolant flow passage 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the normal shaped portions 8N of the rectangular conductor 8. The coolant CL that flows from the second coolant flow passage 21b into the first coolant flow passage 21a flows in the axial direction of the rotating electric machine 1 through the first coolant flow passage 21a.

[0040] The coolant CL branches from the second coolant flow path 21b at the axial center to one axial end side and the other axial end side of the first coolant flow path 21a. 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 the 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, another aspect of the flow path of the coolant CL in one slot 7 of the rotating electric machine 1 of the present disclosure will be generally outlined with reference to Fig. 18 and Fig. 19. Fig. 18 is a see-through perspective view showing another example of the configuration around the coolant flow path shown in Figs. 5 to 7. Fig. 19 is a conceptual diagram showing an extracted portion of the coolant flow path in Fig. 18. As outlined with reference to Fig. 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 in the slot 7 as gaps between the specific shaped portions 8S of the rectangular conductors 8 radially stacked and aligned in 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] In the examples of Fig. 18 and Fig. 19, the axial phase positions of the specific shaped portions 8S of each rectangular conductor 8 are shifted in the axial direction from the outermost rectangular conductor 8 to the innermost rectangular conductor 8 in the radially inward direction. Therefore, the second coolant flow passages 21b formed in the slot 7 from the outer periphery to the inner periphery are inclined from the radial direction according to the axial phase shift of the specific shaped portions 8S. Such second coolant flow passages 21b are provided so as to be inclined from three positions, namely, the central position in the axial direction at the outermost periphery of the slot 7 and two positions spaced from the central position on one axial end side and the other axial end side, toward the inner periphery.

[0044] The coolant CL flowing through the second coolant flow passage 21b flows through the first coolant flow passage 21a that communicates with the second coolant flow passage 21b. The first coolant flow passage 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the normal shaped portions 8N of the rectangular conductor 8. The coolant CL that flows from the second coolant flow passage 21b into the first coolant flow passage 21a flows in the axial direction of the rotating electric machine 1 through the first coolant flow passage 21a.

[0045] The coolant CL branches from the second coolant flow path 21b at the axial center to one axial end side and the other axial end side of the first coolant flow path 21a. 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 the 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 Fig. 20 and Fig. 21, still another aspect of the flow path of the coolant CL in one slot 7 of the rotating electric machine 1 of the present disclosure will be generally outlined. Fig. 20 is a see-through perspective view showing still another example of the configuration around the coolant flow path shown in Fig. 5 to Fig. 7. Fig. 21 is a conceptual diagram showing an extracted portion of the coolant flow path in Fig. 20. As outlined with reference to Fig. 1, the coolant CL is supplied from the outside to an axially intermediate position of 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 in the slot 7 as gaps between the specific shaped portions 8S of the rectangular conductors 8 radially stacked and aligned in 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] In the examples of Figures 20 and 21, the axial phase position of the specific shaped portion 8S of each rectangular conductor 8 changes in a zigzag manner, shifting in one direction, returning, and shifting in the same direction again as it moves radially inward from the outermost rectangular conductor 8 to the innermost rectangular conductor 8. Therefore, the second coolant flow passage 21b formed in the slot 7 from the outer periphery to the inner periphery becomes zigzag in accordance with the axial phase shift of the specific shaped portion 8S described above. Such second coolant flow passage 21b is provided in a zigzag manner from three positions, namely, the central position in the axial direction at the outermost periphery of the slot 7 and two positions spaced from the central position on one axial end side and the other axial end side, toward the inner periphery.

[0049] The coolant CL flowing through the second coolant flow passage 21b flows through the first coolant flow passage 21a that communicates with the second coolant flow passage 21b. The first coolant flow passage 21a is formed along the longitudinal direction of the rectangular conductor 8 as a gap between the normal shaped portions 8N of the rectangular conductor 8. The coolant CL that flows from the second coolant flow passage 21b into the first coolant flow passage 21a flows in the axial direction of the rotating electric machine 1 through the first coolant flow passage 21a.

[0050] The coolant CL branches from the second coolant flow path 21b at the axial center to one axial end side and the other axial end side of the first coolant flow path 21a. 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 the 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 specific shaped portions 8S, each of which has a thickness dimension in a direction perpendicular to its longitudinal direction that is relatively thin in one direction CW and relatively thick in the other direction EW, formed between normal shaped portions 8N that are not specific shaped portions 8S, and the specific shaped portions of the plurality of flat rectangular conductors 8 are juxtaposed in the slot so as to be adjacent to each other, to provide a first coolant flow path 21a formed between the normal shaped portions 8N of the plurality of flat rectangular conductors 8, and a second coolant flow path 21b formed between the specific shaped 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 of (1) above, a plurality of flat square conductors 8 are arranged in parallel in the slot so that the specific shape portions 8S are adjacent to each other, and a first coolant flow path 21a is formed between the normal shape portions 8N of the plurality of flat square conductors 8, and a second coolant flow path 21b is formed between the specific shape portions 8S of the plurality of flat square conductors 8 and the inner wall of the slot 7. For this reason, even if the insulating paper arranged between the inner wall of the slot 7 and the straight portion of the flat square conductor 8 contains a foaming material, when a plurality of flat square conductors 8 are arranged in the slot 7, the first coolant flow path 21a is secured between each adjacent flat square conductor 8, and the second coolant flow path 21b is secured between the slot inner wall (including the insulating member 11 such as insulating paper) and each flat square conductor 8, communicating with the first coolant flow path 21a. The coolant CL flowing through these coolant flow paths can efficiently cool the flat square conductors 8 when the rotating electric machine 1 is in operation.

[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 embodiment (2), the first coolant flow passage 21a is a coolant flow passage formed between the normal shaped portions 8N by connecting in the stacking direction the relatively thick portions (EW) of the specific shaped portions 8S adjacent to each other and arranged side by side in the slot 7. Therefore, a coolant flow passage as the first coolant flow passage 21a is secured between the normal shaped portions 8N of the rectangular conductor 8, and the coolant CL flowing through this coolant flow passage promotes the 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 shaped portion 8S by stacking adjacent specific shaped portions 8S within the slot 7 and connecting the relatively thin thickness dimension portions (CW) in the stacking direction.

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

[0058] Although one embodiment of the rotating electric machine of the present disclosure has been described above, the technical idea of ​​the present disclosure is not limited to this. The detailed configuration may be appropriately changed within the scope of the technical idea of ​​the present disclosure. For example, instead of making the specific shape portion 8S of the rectangular conductor 8 rectangular parallelepiped, the dimensions of the relatively thick part (EW) and the relatively thin part (CW) may be secured by different three-dimensional shapes. [Explanation of symbols]

[0059] 1...Rotary 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 material 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 rectangular conductor has a thickness dimension in a direction perpendicular to its longitudinal direction, the thickness dimension being relatively thin in one direction and relatively thick in the other direction, and the thickness dimension is formed between normal shaped portions that are not the specific shaped portions, A first coolant flow path is formed between the regular shaped portions of the flat conductors by arranging the specific shaped portions of the flat conductors in the slot so that the specific shaped portions of the flat conductors are adjacent to each other; A second coolant flow path is formed between the specific shaped portions of the plurality of rectangular conductors and an inner wall of the slot; A rotating electric machine equipped with the above structure.

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 shaped portions by stacking adjacent specific shaped portions in the slot and connecting the relatively thicker 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 an inner wall of the slot and the specific shaped portion by stacking adjacent specific shaped portions in the slot and connecting the relatively thin portions in the stacking direction.

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