Rotating electric machine

Abstract

To improve the cooling performance of stator coils in rotating electric machines. [Solution] The stator 80 has a cylindrical stator core 81, slots 83 formed axially through the stator core 81 at predetermined intervals in the circumferential direction, and stator coils 82 housed in the slots 83. The rotor 70 is positioned inside the stator 80. The shaft 60 is fitted into the rotor 70 and supports the rotor 70 in a rotatable manner. The rotating electric machine discharges refrigerant from the rotor 70 to the stator 80. The slots 83 have openings 87 that are open at the inner circumferential ends of the stator core 81. The end openings 84, which are the openings 87 at both end ring sides of the stator core 81, have a narrower circumferential dimension than the locations in the slots 83 where the stator coils 82 are housed. At least some of the openings 87 between the end openings 84 have larger openings 85 that are wider in the circumferential direction than the end openings 84.

Description

Technical Field

[0001] The invention of the present application relates to a coil cooling structure of a rotating electrical machine.

Background Art

[0002] Patent Document 1 discloses a coil cooling structure of a rotating electrical machine. In Patent Document 1, refrigerant is discharged to the coil end of the stator coil.

[0003] However, Patent Document 1 cools only the portion of the stator coil through which the refrigerant does not pass by heat conduction from that portion to the portion through which the refrigerant passes. Therefore, the stator coil may not be cooled efficiently.

[0004] Therefore, a method of discharging refrigerant to the stator core is conceivable. FIG. 1 is a schematic diagram showing the structure of a rotating electrical machine of a type in which refrigerant is discharged to the stator core. As shown in FIG. 1, the rotating electrical machine 1 includes a cylindrical stator 80, a rotor 70 disposed inside the stator 80, and a shaft 60 fitted into the rotor 70. A housing conduit (not shown) is formed in the housing (not shown) of the rotating electrical machine 1, a shaft inner conduit 600P is formed in the shaft 60, and a rotor inner conduit 70P is formed in the rotor 70, and these conduits are connected.

[0005] In such a structure, centrifugal force is generated when the shaft 60 and the rotor 70 rotate, and the refrigerant is discharged into the space between the rotor 70 and the stator 80 through the shaft inner conduit 600P and the rotor inner conduit 70P by this centrifugal force, thereby cooling the stator coil 82 provided in the stator 80.

[0006] FIG. 2 is a schematic diagram showing the slot shape of the stator core 81. FIG. 2(a) shows a semi-open shape, and FIG. 2(b) shows an open shape.

Prior Art Documents

Patent Documents

[0007] [Patent Document 1] Japanese Patent Publication No. 2006-115651 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] In a semi-open stator core 81 as shown in Figure 2(a), the opening 87 of the slot 83 is narrow, resulting in less refrigerant directly acting on the stator coil 82, and thus a small cooling effect on the stator coil 82.

[0009] As shown in Figure 2(b), the open slot shape allows for a wider opening 87 in the slot 83, resulting in more refrigerant directly contacting the stator coil 82, which is expected to improve the cooling effect of the stator coil 82. However, the open slot shape can lead to a deterioration in characteristics, such as increased torque ripple.

[0010] Another possible method involves dividing the stator core 81 into two sections at the axial center to form a duct, and then applying refrigerant to the stator coil 82 through this duct. However, this method has the disadvantage of reducing torque.

[0011] For the reasons described above, improving the cooling performance of the stator coil is a challenge in rotating electric machines. [Means for solving the problem]

[0012] The present invention was devised in view of the above-mentioned conventional problems, and one embodiment thereof is a rotating electric machine that discharges a refrigerant from the rotor to the stator, comprising: a stator having a cylindrical stator core; slots formed to penetrate the stator core axially at predetermined intervals in the circumferential direction; and stator coils housed in the slots; a rotor disposed inside the stator; and a shaft fitted into the rotor and supporting the rotor in a manner that allows the rotor to rotate around its axis of rotation, wherein the slots have openings that are open at the inner circumferential ends of the stator core, the end openings which are the openings at both ends on the end ring side of the stator core have a circumferential dimension narrower than the portion of the slot in which the stator coils are housed, and at least a portion of the openings between the end openings has a large opening which has a circumferential dimension wider than the end openings.

[0013] In another embodiment, the stator coil is housed in the slot while wound around insulating paper, and the insulating paper is characterized in that the position corresponding to the opening is open.

[0014] In one embodiment, the large opening is formed at the axial center of the stator core.

[0015] In one embodiment, the large opening is characterized in that multiple openings are formed between the openings at both ends. [Effects of the Invention]

[0016] According to the present invention, it is possible to improve the cooling performance of the stator coil in a rotating electric machine. [Brief explanation of the drawing]

[0017] [Figure 1] A schematic diagram showing a rotating electric machine that discharges refrigerant into the stator core. [Figure 2] A schematic diagram showing the slot shape of a conventional stator core. [Figure 3]Cross-sectional view of a plane passing through the rotation axis of the motor in the embodiment. [Figure 4] Cross-sectional view of a plane perpendicular to the rotation axis of the motor in the embodiment. [Figure 5] Perspective view showing the shaft inner conduit and the rotor inner conduit in the embodiment. [Figure 6] View showing a plate-like member in which holes for forming the rotor inner conduit are formed in the embodiment. [Figure 7] View showing a plate-like member in which holes for forming the rotor inner conduit are formed in the embodiment. [Figure 8] Schematic view showing the slot shape of the stator core in the embodiment. [Figure 9] Schematic view showing the insulating paper wound around the stator coil in the embodiment.

Mode for Carrying Out the Invention

[0018] Hereinafter, an embodiment of the rotating electrical machine in the present invention will be described in detail based on FIGS. 3 to 9.

[0019] [Embodiment] FIG. 3 is a cross-sectional view taken along a plane passing through the rotation axis of the motor according to the present embodiment. FIG. 4 is a cross-sectional view taken along a plane perpendicular to the rotation axis of the motor according to the present embodiment.

[0020] The motor 1 is mounted on, for example, an electric vehicle to rotate the wheels of the electric vehicle. Further, the motor 1 is an example of a rotating electrical machine. As shown in FIGS. 3 and 4, the motor 1 includes a housing 20, a housing 30, a housing forming member 40, a housing forming member 50, a shaft 60, a rotor 70, and a stator 80. In the following description, an X-axis which is an axis parallel to the rotation axes of the shaft 60 and the rotor 70, a Y-axis perpendicular to the X-axis, and a Z-axis perpendicular to the X-axis and the Y-axis are used. Also, the X-axis, Y-axis, and Z-axis form a right-handed system.

[0021] The housing 20 is a cylindrical component that houses the shaft 60, rotor 70, stator 80, etc. The housing 20 also has conduits 21, a filter 22, and conduits 23 attached to it, and an internal housing conduit 20P is formed inside. Conduit 21 is a pipe through which a refrigerant (e.g., cooling oil) flows to cool each part of the motor 1, and is attached to the housing 20 along the Z direction. The internal housing conduit 20P is a cylindrical pipe through which the refrigerant flows from conduit 21. The filter 22 prevents foreign matter contained in the refrigerant that has flowed down to the -Z side of the housing 20 or housing 30 from entering the conduit 23. Conduit 23 is a cylindrical pipe through which the refrigerant that has flowed down to the -Z side of the housing 20 or housing 30 flows.

[0022] The housing 30 is a cylindrical member attached to the -X end of the housing 20. The housing 30 also has an internal conduit 30P formed inside. The internal conduit 30P is a cylindrical tube through which refrigerant flows from the internal conduit 20P. Furthermore, the housing 30 has a hole into which the -X end of the shaft 60 is inserted, and a hole into which a bearing 64 (described later) is inserted.

[0023] The housing forming member 40 is a disc-shaped member that covers the opening on the +X side of the housing 20. The housing forming member 40 also has a hole into which the +X end of the shaft 60 is inserted, a hole into which a bearing 61 is mounted, a hole into which a bearing 62 is mounted, and a hole into which a bearing 63 is mounted.

[0024] The housing forming member 50 is a plate-shaped member that covers the opening on the -X side of the housing 30. The housing forming member 50 also has an internal housing conduit 50P formed on it. The internal housing conduit 50P is a cylindrical pipe through which the refrigerant flows in from the internal housing conduit 30P.

[0025] The shaft 60 is a rod-shaped member that is fitted into the rotor 70 and supports the rotor 70 in a manner that allows the rotor 70 to rotate around its axis of rotation. The end of the shaft 60 on the +X side is inserted into a hole formed in the housing forming member 40 and is supported in a manner that allows it to rotate by bearings 61, 62, and 63 attached to the housing forming member 40. The end of the shaft 60 on the -X side is inserted into a hole formed in the housing 30 and is supported in a manner that allows it to rotate by bearing 64 attached to the housing 30.

[0026] Figure 5 is a perspective view showing the shaft conduit according to this embodiment. As shown in Figure 3, the shaft 60 has a shaft conduit 60P formed therein. The shaft conduit 60P comprises conduit 601P, conduit 602P, and conduit 603P. As shown in Figure 3, conduit 601P is a cylindrical tube into which refrigerant flows from the housing conduit 50P and leads to the outlet of the housing conduit 50P. As shown in Figures 3 to 5, conduit 602P is a cylindrical tube into which refrigerant flows from conduit 601P, and the cross-sectional area of ​​the plane parallel to the YZ plane is larger than that of conduit 601P. As shown in Figures 3 to 5, conduit 603P is a cylindrical tube into which refrigerant flows from conduit 602P and leads to the inlet of the rotor conduit 70P, which will be described later.

[0027] The rotor 70 is a component that rotates due to the magnetic force generated by the stator 80 and is located inside the stator 80. The rotor 70 is manufactured by stacking multiple annular plate-shaped members in the direction of the rotation axis. These plate-shaped members are made of electromagnetic steel. These plate-shaped members have a hole in the center into which the shaft 60 is fitted, and holes for fitting permanent magnets are regularly formed along the circumference.

[0028] Figure 5 is a perspective view showing the rotor conduit according to this embodiment. The rotor 70 is equipped with a rotor conduit 70P. The rotor conduit 70P is a pipe through which refrigerant flows in from the conduit 603P. The rotor conduit 70P has an inlet that leads to the outlet of the conduit 603 and an outlet that leads to the space between the stator 80 and the rotor 70. The rotor conduit 70P is formed by stacking plate-shaped members, each having at least one hole, such that the openings of the holes overlap in a direction parallel to the rotation axis of the rotor 70. Specifically, the rotor conduit 70P is formed by stacking two types of plate-shaped members, each having a hole at a different position.

[0029] Figure 6 shows a plate-shaped member having holes for forming conduits inside the rotor according to this embodiment. As shown in Figure 6, the plate-shaped member 71 has a permanent magnet insertion hole 701, a permanent magnet insertion hole 703, a stress relief hole 705, a shaft insertion hole 706, a conduit forming hole 711H, a conduit forming hole 712H, a conduit forming hole 713H, and a conduit forming hole 714H.

[0030] As shown in Figure 6, there are a total of eight permanent magnet mounting holes 701 and 703, each formed at equal intervals in the circumferential direction. Each permanent magnet mounting hole 701 is a hole that penetrates the plate-shaped member 71, and as shown in Figure 4, a permanent magnet 702 is fitted into it. Similarly, each permanent magnet mounting hole 703 is a hole that penetrates the plate-shaped member 71, and as shown in Figure 4, a permanent magnet 704 is fitted into it.

[0031] Furthermore, a pair of permanent magnets 702 and 704 adjacent to each other in the circumferential direction form one pole of the motor 1. For example, permanent magnets 702 and 704 form either a south pole or a north pole in the region M shown in Figure 4. Similarly, other pairs of permanent magnets 702 and 704 also form such poles.

[0032] As shown in Figure 6, a total of four stress relief holes 705 are formed, all at equal intervals in the circumferential direction. Each of the stress relief holes 705 is a hole that penetrates the plate-shaped member 71 and is formed for purposes such as relieving stress concentrated at specific points on the plate-shaped member 71 due to the centrifugal force generated as the rotor 70 rotates, and for the purpose of reducing the weight of the rotor 70. In addition, bolts may be inserted into the stress relief holes 705 when the rotor 70 is assembled.

[0033] The shaft insertion hole 706 is a circular hole located in the center of the plate-shaped member 71, and penetrates the plate-shaped member 71. The shaft 60 is inserted into the shaft insertion hole 706.

[0034] The conduit-forming holes 711H, 712H, 713H, and 714H are all recesses formed on the surface of the plate-shaped member 71. Specifically, the conduit-forming holes 711H, 712H, 713H, and 714H are holes in which the surface of the plate-shaped member 71 is recessed in the +X direction in an elongated rectangular region perpendicular to the rotation axis of the rotor 70. Furthermore, the depth of the conduit-forming holes 711H, 712H, 713H, and 714H is the same throughout.

[0035] The conduit-forming holes 711H, 712H, 713H, and 714H are all located at the same position in the circumferential direction and have equal short-side lengths. Furthermore, the long sides of the conduit-forming holes 711H, 712H, 713H, and 714H are parallel to a straight line perpendicular to the rotation axis of the rotor 70. Additionally, the conduit-forming holes 711H, 712H, 713H, and 714H are arranged outward from the shaft insertion hole 706 in the order of 711H, 712H, 713H, and 714H. Moreover, the conduit-forming holes 711H, 712H, 713H, and 714H are formed between two adjacent poles.

[0036] Figure 7 shows a plate-shaped member having holes for forming conduits inside the rotor according to this embodiment. As shown in Figure 7, the plate-shaped member 72 has a permanent magnet insertion hole 701, a permanent magnet insertion hole 703, a stress relief hole 705, a shaft insertion hole 706, a conduit forming hole 721H, a conduit forming hole 722H, and a conduit forming hole 723H. The permanent magnet insertion hole 701, permanent magnet insertion hole 703, stress relief hole 705, and shaft insertion hole 706 shown in Figure 7 are the same as the permanent magnet insertion hole 701, permanent magnet insertion hole 703, stress relief hole 705, and shaft insertion hole 706 shown in Figure 6, respectively.

[0037] The conduit-forming holes 721H, 722H, and 723H are all recesses formed on the surface of the plate-shaped member 72. Specifically, the conduit-forming holes 721H, 722H, and 723H are holes in which the surface of the plate-shaped member 71 is recessed toward the -X direction in an elongated rectangular region perpendicular to the rotation axis of the rotor 70. Furthermore, the depth of the conduit-forming holes 721H, 722H, and 723H is the same throughout.

[0038] The conduit-forming holes 721H, 722H, and 723H are located at the same position in the circumferential direction and have the same short-side length as the aforementioned conduit-forming holes 711H, 712H, 713H, and 714H. Furthermore, the long sides of the conduit-forming holes 721H, 722H, and 723H are parallel to a straight line perpendicular to the rotation axis of the rotor 70. Additionally, the conduit-forming holes 721H, 722H, and 723H are arranged outward from the shaft insertion hole 706 in the order of conduit-forming holes 721H, 722H, and 723H. Moreover, the conduit-forming holes 721H, 722H, and 723H are formed between two adjacent poles.

[0039] Plate-shaped member 71 and plate-shaped member 72 are stacked such that the openings of the conduit-forming holes 711H, 712H, 713H, or 714H overlap in the X direction. In this case, the +Z direction side of the opening of the conduit-forming hole 711H and the -Z direction side of the opening of the conduit-forming hole 721H overlap in the X direction. Also, in this case, the +Z direction side of the opening of the conduit-forming hole 721H and the -Z direction side of the opening of the conduit-forming hole 712H overlap in the X direction.

[0040] Similarly, in the above case, the +Z direction side of the opening of the conduit-forming hole 712H and the -Z direction side of the opening of the conduit-forming hole 722H overlap in the X direction. In the above case, the +Z direction side of the opening of the conduit-forming hole 722H and the -Z direction side of the opening of the conduit-forming hole 713H overlap in the X direction. In the above case, the +Z direction side of the opening of the conduit-forming hole 713H and the -Z direction side of the opening of the conduit-forming hole 723H overlap in the X direction. In the above case, the +Z direction side of the opening of the conduit-forming hole 723H and the -Z direction side of the opening of the conduit-forming hole 714H overlap in the X direction.

[0041] The rotor conduit 70P is formed along a straight line perpendicular to the rotation axis of the rotor 70, due to the shape and arrangement of the conduit forming holes 711H and 721H described above, and meanders within the plane containing that straight line. Furthermore, the rotor conduit 70P leads to the outlet of conduit 603P and is a tube that leads to the space between the stator 80 and the rotor 70.

[0042] Furthermore, the rotor conduit 70P is perpendicular to the rotation axis of the rotor 70, and its outlet is formed within a predetermined distance from the intersection of a plane passing through the center in the direction of the rotation axis of the rotor 70 and the stator coil 82 attached to the stator 80. The portion of the stator coil 82 closest to this intersection has greater eddy current losses and is more prone to overheating than other portions. For this reason, the predetermined distance must be such that a sufficient amount of coolant can be supplied from the rotor conduit 70P to the portion of the stator coil 82 that is close to the intersection and experiences greater overheating due to eddy current losses than other portions of the stator coil 82.

[0043] The rotor 70 also includes a clamp 73, a clamp 74, a clamp cover 75, and a clamp cover 76. Clamps 73 and 74 are annular members that clamp and fasten plate-shaped members 71, 72, and other plate-shaped members forming the rotor 70 in the X direction. Clamp cover 75 is an annular member that covers the end face of the rotor 70 on the +X direction side and the clamp 73. Clamp cover 76 is an annular member that covers the end face of the rotor 70 on the -X direction side and the clamp 74.

[0044] As shown in Figures 3 and 4, the stator 80 comprises a stator core 81 and a stator coil 82. The stator core 81 is a cylindrical member into which the shaft 60 and rotor 70 are inserted, and has multiple teeth formed on its inside. The stator coil 82 is formed by winding copper wire around the teeth. The stator coil 82 also generates a magnetic force to rotate the rotor 70 when energized.

[0045] Figure 8 is a schematic diagram showing the slot shape of the stator core 81 in this embodiment 1. As shown in Figure 8, the stator core 81 has slots 83 that penetrate axially at predetermined intervals in the circumferential direction, and the stator coils 82 are housed in these slots 83. The slots 83 have openings 87 that are open at the inner circumferential end of the stator core 81.

[0046] The end ring openings 84 at both ends of the stator core 81, which are the openings 87 at both ends on the end ring side, have a shape that is narrower in the circumferential direction than the area in the slot 83 where the stator coil 82 is housed. At least some of the openings 87 between the end ring openings 84 have large openings 85 that are wider in the circumferential direction than the end ring openings 84.

[0047] In other words, the openings 84 at both ends of the opening 87 are semi-open, and a large opening 85 between the openings 84 at both ends is an open slot shape.

[0048] At least one large opening 85 is provided in each slot 83 (opening 87). The large opening 85 is formed, for example, at the axial center of the stator core 81. Multiple large openings 85 may be formed depending on the heat generation location and temperature distribution of the stator coil 82. The axial length of the large opening 85 may also be extended depending on the heat generation location and temperature distribution. However, the end ring portion of the stator core 81 is semi-open to prevent the stator coil 82 housed in the slot 83 from falling out.

[0049] The stator coil 82 is installed in the slot 83 with insulating paper wound around it. Figure 9 is a schematic diagram showing the insulating paper wound around the stator coil 82. Figure 9(a) shows a cross-sectional view of the area where openings 84 at both ends are formed (where the slot 83 is semi-open), and Figure 9(b) shows a cross-sectional view of the area where a large opening 85 is formed (where the slot 83 is open).

[0050] As shown in Figures 9(a) and (b), the stator coil 82 is housed in the slot 83 with insulating paper 86 wound around it in the circumferential direction.

[0051] As shown in Figure 9(a), at the locations where the openings 84 at both ends are formed, the insulating paper 86 on the inner circumference end side of the stator core 81 is folded to match the shape of the slot 83. The insulating paper 86 is left open at the positions corresponding to the openings 84 at both ends.

[0052] As shown in Figure 9(b), at the location where the large opening 85 is formed, the insulating paper 86 is not provided on the inner circumferential end surface of the stator core 81. In other words, the insulating paper 86 is open in the position corresponding to the large opening 85.

[0053] Next, the flow of refrigerant according to this embodiment will be described with reference to Figures 3 and 4. After flowing into conduit 21, the refrigerant flows into conduit 601P, which constitutes shaft conduit 60P, via housing conduit 20P, housing conduit 30P, and housing conduit 50P, as shown by the arrows in Figure 3. Next, the refrigerant flows into rotor conduit 70P, via conduits 601P, 602P, and 603P, which constitute shaft conduit 60P.

[0054] The refrigerant present inside the conduit 603P or the rotor conduit 70P is released into the space between the stator 80 and the rotor 70 by the centrifugal force generated by the rotation of the shaft 60 and the rotor 70, cooling the stator core 81, stator coils 82, etc. At this time, a large opening 85 is formed in the axial center of the inner circumference end of the stator core 81, and the insulating paper 86 is also open at the location corresponding to the opening 87, so that a large amount of refrigerant is applied to the stator coils 82. Next, the refrigerant flows down to the -Z direction side of the housing 20 or housing 30 through the space between the stator 80 and the rotor 70.

[0055] The refrigerant then flows into the conduit 23 via the filter 22. The refrigerant that flows into the conduit 23 flows into a pump installed at the end of the conduit 23 and is sent to a water-cooled cooler installed at the end of the pump. The refrigerant cooled by the water-cooled cooler then flows back into the conduit 21.

[0056] As described above, according to this embodiment, the motor 1 can efficiently cool the stator coil 82 by directly supplying refrigerant to the space between the stator 80 and the rotor 70. The motor 1 can also efficiently cool the shaft 60 by supplying refrigerant to the shaft conduit 60P. The motor 1 can also efficiently cool the rotor 70 by supplying refrigerant to the rotor conduit 70P. Furthermore, by efficiently cooling the stator coil 82, the motor 1 can reduce the volume of the stator coil 82, thereby reducing the cost of manufacturing the stator coil 82 and enabling the motor 1 to be miniaturized.

[0057] Furthermore, the rotor conduit 70P is perpendicular to the rotation axis of the rotor 70, and its outlet is formed within a predetermined distance from the intersection of a plane passing through the center in the direction of the rotation axis of the rotor 70 and the stator coil 82 attached to the stator 80. As a result, the motor 1 can supply a sufficient amount of coolant to the part of the stator coil 82 where heat generation due to eddy current losses is particularly large, and cool that part sufficiently.

[0058] Furthermore, the rotor conduit 70P is formed by stacking two types of plate-shaped members 71 and 72, each having holes formed in different positions. This allows the motor 1 to form the rotor 70 using only three types of plate-shaped members: plate-shaped member 71, plate-shaped member 72, and plate-shaped members without conduit-forming holes 711H and 721H for forming the rotor conduit 70P. Consequently, the motor 1 can reduce the number of molds required to manufacture the rotor 70 to just three, thereby lowering the cost required to manufacture the rotor 70.

[0059] Furthermore, the rotor conduit 70P is formed along a straight line perpendicular to the rotation axis of the rotor 70. This allows the motor 1 to efficiently transmit the centrifugal force generated by the rotation of the rotor 70 to the coolant present inside the rotor conduit 70P, and to efficiently release the coolant into the space between the stator 80 and the rotor 70. Therefore, the motor 1 efficiently cools the stator coil 82.

[0060] Furthermore, the conduit-forming holes 711H, 712H, 713H, and 714H are formed between two adjacent poles in the rotor 70. Similarly, the conduit-forming holes 721H, 722H, and 723H are formed between two adjacent poles in the rotor 70. As a result, the motor 1 can suppress the occurrence of a phenomenon in which magnetic flux saturation occurs and torque decreases due to the narrowing of the path of magnetic flux passing through each pole.

[0061] Furthermore, by forming a large opening 85 in at least a portion of the space between the openings 84 at both ends, the refrigerant can more easily reach the stator coil 82 at the location of the large opening 85, thereby improving the cooling performance of the stator coil 82.

[0062] Furthermore, the stator coil 82 tends to have a hot spot near the axial center of the stator core 81. By forming a large opening 85 near the axial center of the stator core 81, the coolant can be directly applied to the hot spot of the stator coil 82, further improving the cooling performance of the stator coil 82.

[0063] Furthermore, the stator coil 82 is housed in the slot 83 while wrapped in insulating paper 86. In this embodiment, the insulating paper 86 has an open section corresponding to the opening 87, which allows the refrigerant to easily reach the stator coil 82, further improving the cooling performance.

[0064] Furthermore, by making the openings 84 at both ends of the opening 87 on the end ring side semi-open, it is possible to prevent the stator coil 82 housed in the slot 83 from coming out of the slot 83. Also, by making the openings 84 at both ends of the opening 87 on the end ring side semi-open, it is possible to suppress deterioration of characteristics such as an increase in torque ripple.

[0065] Although the present invention has been described in detail only with respect to the specific examples described above, it will be obvious to those skilled in the art that a wide variety of modifications and alterations are possible within the scope of the technical concept of the present invention, and it is natural that such modifications and alterations fall within the scope of the claims.

[0066] In the above-described embodiment, the example given was that the conduit-forming holes 711H, etc., shown in Figure 6, are recesses formed on the surface of the plate-like member 71, but the embodiment is not limited to this. Similarly, the example given was that the conduit-forming holes 721H, etc., shown in Figure 7, are recesses formed on the surface of the plate-like member 72, but the embodiment is not limited to this. At least one of the holes forming the conduits inside the rotor may be a through-hole that penetrates the plate-like member.

[0067] Furthermore, the rotor conduit 70P may have an outlet formed within a predetermined distance from the portion of the stator coil 82 attached to the stator 80 whose temperature exceeds a predetermined temperature. This predetermined distance must be such that a sufficient amount of coolant can be supplied from the rotor conduit 70P to the portion of the stator coil 82 whose temperature exceeds the predetermined temperature. As a result, when a specific portion of the stator coil 82 reaches a temperature above a predetermined temperature due to the influence of the structure of the housing 20 or other devices surrounding the stator coil 82, the motor 1 can supply a sufficient amount of coolant to that portion and cool it sufficiently.

[0068] Furthermore, although the above-described embodiment explained using the case where the rotor conduit 70P is formed along a straight line perpendicular to the rotation axis of the rotor 70 as an example, it is not limited to this. The rotor conduit according to this embodiment can take any path from the inlet to the outlet. For example, the rotor conduit according to this embodiment may be formed along a straight line that passes through the rotation axis of the rotor 70 but is not perpendicular to the rotation axis of the rotor 70 from the inlet to the outlet. Also, for example, the rotor conduit according to this embodiment may be bent along the way. In these cases, three or more plate-like members with different hole patterns will be required.

[0069] Furthermore, although the above-described embodiment uses the example of a motor 1 being a motor mounted on an electric vehicle for rotating the wheels of the electric vehicle, it is not limited to this. The motor according to this embodiment may be a motor used for purposes other than rotating the wheels of an electric vehicle.

[0070] Furthermore, although the above-described embodiment uses motor 1 as an example of a rotating electric machine, it is not limited to this. The rotating electric machine according to this embodiment may be a generator that converts mechanical energy into electrical energy, rather than a motor 1 that converts electrical energy into mechanical energy. [Explanation of symbols]

[0071] 1...Rotating electric machine (motor), 60...Shaft, 70...Rotor, 80...Stator, 81...Stator core, 82...Stator coil, 83...Slot, 84...Openings at both ends, 85...Large opening, 86...Insulating paper, 87...Opening

Claims

1. A stator comprising a cylindrical stator core, slots formed axially through the stator core at predetermined intervals in the circumferential direction, and stator coils housed within the slots, A rotor positioned inside the stator, The rotor is fitted into the rotor and supports the rotor in such a manner that the rotor can rotate around its axis of rotation, A rotating electric machine that discharges a refrigerant from the rotor to the stator, The rotating electric machine is characterized in that the slot has an opening at the inner circumferential end of the stator core, the end openings at both ends of the stator core on the end ring side are narrower in the circumferential direction than the portion of the slot in which the stator coil is housed, and at least some of the openings between the end openings are formed as large openings that are wider in the circumferential direction than the end openings.

2. The stator coil is housed in the slot while wrapped in insulating paper. The rotating electric machine according to claim 1, characterized in that the insulating paper has an open position corresponding to the opening.

3. The rotating electric machine according to claim 1, characterized in that the large opening is formed at the axial center of the stator core.

4. The rotating electric machine according to claim 1, characterized in that a plurality of the large openings are formed between the openings at both ends.

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