Rotary electric machine

Abstract

To provide a rotary electric machine capable of improving a cooling performance by a coolant medium.SOLUTION: Each of core blocks 200A and 200B are alternately arranged to a stator peripheral direction at a predetermined angle pitch θ, and comprises a plurality of coolant passages 202 203 that is extended to a stator radial direction. In each coolant passage 202, a coolant is supplied from an external part, and is extended to a first region E1 on a radial inner peripheral side from a core outer periphery, and each coolant passage 203 is extended to a second region E2 on a radial inner peripheral side from the first region E1. In the core blocks 200A and 200B, the inner peripheral end region of each coolant passage 202 of the core block 200A are communicated with an outer peripheral end region of each coolant passage 203 of the core block 200B, and is laminated so that the inner peripheral end region of each coolant passage 202 of the core block 200B is communicated to the outer peripheral end region of each coolant passage 203 of the core block 200A.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] Conventionally, a method of dripping refrigerant from above a stator core is known as a cooling method for a rotating electric machine (see Patent Document 1). In Patent Document 1, multiple refrigerant guide vanes extending in the axial direction are provided on the outer peripheral surface of the stator core. The refrigerant that drips onto the outer peripheral surface of the stator core and flows down the outer peripheral surface is guided in the axial direction of the stator by the multiple refrigerant guide vanes, and is ultimately guided to the coil end portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-115994 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology described in Patent Document 1, the refrigerant is dropped onto the outer peripheral surface of the stator for cooling, making it difficult to ensure sufficient coil cooling performance. [Means for solving the problem]

[0005] A rotating electric machine according to one embodiment of the present invention is a rotating electric machine comprising a rotor and a stator having a plurality of slots, wherein the stator core of the stator has first and second core blocks stacked in the axial direction, each of the first and second core blocks being arranged alternately at a predetermined angular pitch in the stator circumferential direction and comprising a plurality of first and second flow paths extending in the stator radial direction, wherein the first flow path is supplied with refrigerant from the outside and extends from the outer periphery of the core to a predetermined radial region on the radially inner side, and the second flow path extends from the predetermined radial region to a region near the slots on the radially inner side, and the first and second core blocks are stacked in the axial direction so that an inner end region of the first flow path of the first core block is connected to an outer periphery end region of the second flow path of the second core block, and an inner end region of the first flow path of the second core block is connected to an outer periphery end region of the second flow path of the first core block. Effect of the Invention

[0006] According to the present invention, it is possible to improve the cooling performance by the refrigerant. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a diagram showing a main part of a rotating electric machine. [Diagram 2] FIG. 2 is a diagram showing a plurality of core blocks stacked in the axial direction. [Diagram 3] FIG. 2 is a front view of a core block laminate. [Figure 4] 4 is a diagram showing one of the pair of core blocks shown in FIG. 3. [Diagram 5] 4 is a diagram showing the other of the pair of core blocks shown in FIG. 3. FIG. [Figure 6] 4 is a front view of core blocks disposed at both ends of the stator core. FIG. [Figure 7] FIG. 4 is a cross-sectional view taken along line D1-D1 of FIG. [Figure 8] 13 is a front view of a core block laminate in Modification 1. FIG. [Figure 9] FIG. 13 is a diagram showing a core block of a first modified example. [Figure 10] 9 is a cross-sectional view taken along line D2-D2 of FIG. 8. [Figure 11] 11 is a diagram showing an example of a magnetic flux density distribution when a stator core is not provided with a coolant flow passage; FIG. [Figure 12] FIG. 13 is a diagram showing a magnetic flux density distribution in a comparative example. [Figure 13] FIG. 13 is a diagram showing one core block in a comparative example. [Figure 14] FIG. 13 is a diagram showing the other core block in the comparative example. [Figure 15] FIG. 10 is a diagram showing a magnetic flux density distribution when the core block shown in FIGS. [Figure 16] FIG. 11 is a diagram showing a torque improvement rate based on a comparative example. [Figure 17] FIG. 11 is a diagram showing a core block laminate according to the second embodiment. [Figure 18] 18 is a diagram showing one core block of the core block laminate shown in FIG. 17. FIG. [Figure 19] 18 is a diagram showing the other core block of the core block laminate shown in FIG. 17. FIG. [Figure 20] FIG. 18 is a cross-sectional view taken along line D3-D3 of FIG. 17. [Figure 21] 13 is a diagram showing a core block laminate in Modification 2. FIG. [Figure 22] 22 is a diagram showing one core block of the core block laminate shown in FIG. 21. FIG. [Diagram 23] 22 is a diagram showing the other core block of the core block laminate shown in FIG. 21. FIG. [Figure 24] 13 is a diagram showing another example of a core block in the second modification example. FIG. [Diagram 25] FIG. 11 is a diagram showing a torque improvement rate in the second embodiment. [Figure 26] 23 is a diagram showing another example of the core block shown in FIG. 22. [Figure 27] FIG. 24 is a diagram showing a magnetic flux density distribution when the core block shown in FIGS. 22 and 23 is used. [Figure 28]27 is a diagram showing a magnetic flux density distribution when the core block shown in FIG. 26 is used. FIG. [Figure 29] FIG. 11 is a diagram showing a stator core 20 according to a third embodiment. [Diagram 30] FIG. 13 is a diagram showing a core block laminate according to a third embodiment. [Diagram 31] 31 is a diagram showing one core block of the core block laminate shown in FIG. 30. FIG. [Diagram 32] 31 is a diagram showing the other core block of the core block laminate shown in FIG. 30. FIG. [Diagram 33] 13A to 13C are diagrams showing core blocks arranged on both ends of a stator core in a third embodiment. [Diagram 34] 31 is a cross-sectional view taken along line D4-D4 of FIG. 30. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and appropriate omissions and simplifications have been made for clarity of explanation. In addition, in the following description, the same or similar elements and processes are given the same reference numerals, and duplicate explanations may be omitted. Note that the contents described below are merely examples of the embodiment of the present invention, and the present invention is not limited to the following embodiment, and can be implemented in various other forms.

[0009] (First embodiment) 1 is a view of a stator 2 and a rotor 3 of a rotating electric machine 1, viewed from the positive direction of the z coordinate axis along the axial direction of the rotor 3. The rotating electric machine 1 includes a case 4, an annular stator 2 arranged in the case 4, and a rotor 3 arranged on the inner circumferential side of the stator 2. The stator 2 includes a stator core 20 laminated in the axial direction, and a stator coil 21 housed in a slot 201 of the stator core 20. The case 4 is provided with a refrigerant introduction section 42 for introducing a refrigerant into the case. A through hole 420 is formed in the refrigerant introduction section 42. The coil conductor used for the stator coil 21 is not limited to a rectangular wire, and a round wire may be used.

[0010] As shown in Fig. 2, the stator core 20 is formed by stacking four core blocks 200A, 200B, and 210 in the axial direction. The core block 210, the core block 200A, the core block 200B, and the core block 210 are arranged in this order from the positive direction of the z axis. The core blocks 200A, 200B, and 210 are formed by stacking electromagnetic steel sheets. An annular refrigerant flow path 421 is formed between the inner peripheral surface of the case 4 and the outer peripheral surfaces of the core blocks 200A and 200B. The through hole 420 of the refrigerant introduction part 42 is connected to the refrigerant flow path 421.

[0011] Fig. 3 is a front view of a laminate of core blocks 200A and 200B. In Fig. 3, core block 200A is disposed on the front side of the figure, and core block 200B is disposed behind it (z-axis negative side). Core block 200A and core block 200B are configured of core blocks of the same shape. That is, core blocks 200A and 200B are formed by laminating electromagnetic steel sheets of the same shape. As will be described later, core block 200B is rotated (transposed) clockwise by angle θ (see Fig. 5) with respect to core block 200A about stator axis C.

[0012] The core blocks 200A and 200B are formed with three types of refrigerant flow paths 202, 203, and 204. The refrigerant flow paths 202-204 shown by solid lines are formed in the core block 200A, and the refrigerant flow paths 202-204 shown by dashed lines are formed in the core block 200B.

[0013] FIG. 4 is a front view of the core block 200A in FIG. 3. As described above, the core block 200A has three types of refrigerant flow paths 202, 203, and 204. The refrigerant flow path 202 extends in the radial direction and has an opening on the outer periphery of the core. The inner peripheral end region of the refrigerant flow path 202 extends to the annular first region E1. The refrigerant flow path 203 extending in the radial direction extends from the first region E1 to the annular second region E2 set near the slot 201 on the inner peripheral side. The refrigerant flow paths 202 and 203 extending in the stator radial direction penetrate the core block 200A in the stator axial direction. The refrigerant flow path 204 arranged in the second region E2 extends in the stator axial direction so as to penetrate the core block 200A.

[0014] 4, the refrigerant flow paths 202 and refrigerant flow paths 203 are alternately arranged in the circumferential direction at a pitch θ that is the same as the slot pitch (angle θ). In addition, the multiple refrigerant flow paths 204 arranged in the circumferential direction at a pitch of 2θ are set to have the same circumferential position as the refrigerant flow paths 202.

[0015] Fig. 5 shows a front view of the core block 200B in Fig. 3. The shape is exactly the same as the core block 200A shown in Fig. 4. However, the arrangement in the circumferential direction of the stator is different from that of the core block 200A. In the core block 200B shown in Fig. 5, the circumferential position of the refrigerant flow path marked with reference numeral 202-1 among the multiple refrigerant flow paths 202 is shifted by an angle θ in the clockwise direction from that in the core block 200A shown in Fig. 4. When stacking the core blocks 200A and 200B, they are stacked so that the 0° position in Fig. 4 and the 0° position in Fig. 5 coincide with each other.

[0016] 3, when core block 200A and core block 200B are laminated, an inner peripheral end region of coolant flow path 202 of core block 200A faces an outer peripheral end region of coolant flow path 203 of core block 200B. As a result, coolant flow path 202 of core block 200A and coolant flow path 203 of core block 200B communicate with each other. Similarly, an inner peripheral end region of coolant flow path 202 of core block 200B faces an outer peripheral end region of coolant flow path 203 of core block 200A, and these coolant flow paths 202, 203 communicate with each other.

[0017] Moreover, an inner peripheral end region of the coolant flow path 203 of the core block 200A faces the coolant flow path 204 of the core block 200B. Similarly, an inner peripheral end region of the coolant flow path 203 of the core block 200B faces the coolant flow path 204 of the core block 200A. As a result, the coolant flow paths 203 and 204 of the stacked core blocks 200A and 200B communicate with each other.

[0018] Fig. 6 is a front view of the core block 210 of Fig. 2. As shown in Figs. 1 and 2, the core block 210, whose outer diameter is set larger than those of the core blocks 200A and 200B, is fixed to the inner circumference of the case 4. The core block 210 has refrigerant flow paths 204 formed at the same positions as the refrigerant flow paths 204 of the core blocks 200A and 200B. That is, in the core block 210, the refrigerant flow paths 204 are arranged at a pitch θ.

[0019] Fig. 7 is a diagram showing a cross section taken along line D1-D1 in Fig. 3. Although Fig. 3 does not show the core block 210 and the stator coil 21 in the slot 201, Fig. 8 also shows the core block 210 and the stator coil 21. The inner circumferential short region of the refrigerant flow path 202 of the core block 200B faces the outer circumferential end region of the refrigerant flow path 203 of the core block 200A. The refrigerant flow path 204 of the core block 200B and the core block 210 on the left side of the figure faces the inner circumferential end region of the refrigerant flow path 203 of the core block 200A. The refrigerant flow path 204 of the core block 200B faces the refrigerant flow path 204 of the core block 210 on the right side of the figure.

[0020] The arrows in Fig. 7 indicate the flow of the coolant. The coolant supplied from the outside is introduced into an annular coolant flow path 421 between the case 4 and the core blocks 200A, 200B from a through hole 420 in the case 4 shown in Fig. 1. The coolant in the coolant flow path 421 flows into the coolant flow path 202 in the core block 200B, passes through the coolant flow paths 203, 204, and flows out from the end face of the core block 210 in the coil end direction. As the coolant flows through the core blocks 200A, 200B, 210 in this manner, the stator core 20 is cooled, and further, the stator coil 21 in the slot 201 is cooled by the stator core 20.

[0021] (Variation 1) 8 to 10 are diagrams showing a first modified example of the core blocks 200A and 200B described above. FIG. 8 is a diagram showing a laminate of core blocks 200C and 200D as viewed from the front. Core block 200C is disposed on the front side of the figure, and core block 200D is disposed behind it (z-axis negative side). Core block 200C and core block 200D are composed of core blocks of the same shape. In FIG. 8, refrigerant flow paths 202 and 203 shown by solid lines are formed in core block 200C. On the other hand, refrigerant flow paths 202 and 203 shown by dashed lines are formed in core block 200D.

[0022] FIG. 9 is a front view of the core block 200C in FIG. 8. In the core block 200C, a plurality of refrigerant channels 202, 203 are alternately arranged at a pitch θ in the circumferential direction. In the core block 200C, the circumferential positions of the refrigerant channels 202, 203 are set to the same positions as the slots 201. The refrigerant channel 202 extends from the outer periphery of the core to the first region E1 on the radially inner side, similar to the refrigerant channel 202 of the core block 200A shown in FIG. 4. The refrigerant channel 203 extends from the first region E1 to the radially inner side, similar to the refrigerant channel 203 of the core block 200A shown in FIG. 4. The inner peripheral end region of the refrigerant channel 203 communicates with the slots 201.

[0023] The core block 200D in the stacked state of Fig. 8 is obtained by rotating the core block 200C shown in Fig. 9 by an angle θ in the circumferential direction. When the core blocks 200C and 200D are stacked as shown in Fig. 8, the inner peripheral end region of the refrigerant flow path 202 of the core block 200C faces the outer peripheral end region of the refrigerant flow path 203 of the core block 200D. Similarly, the inner peripheral end region of the refrigerant flow path 202 of the core block 200D faces the outer peripheral end region of the refrigerant flow path 203 of the core block 200C. As a result, the refrigerant flow paths 202 and 203 of the core block 200C are respectively connected to the opposing refrigerant flow paths 203 and 202 of the core block 200D.

[0024] Fig. 10 is a diagram showing a cross section taken along line D2-D2 in Fig. 8. Note that Fig. 8 does not show the core block 210 and the stator coil 21 in the slot 210, but Fig. 10 also shows the core block 210 and the stator coil 21. As described above, the inner peripheral short region of the refrigerant flow path 202 of the core block 200D faces the outer peripheral end region of the refrigerant flow path 203 of the core block 200C. Also, the inner peripheral end region of the refrigerant flow path 203 of the core block 200C communicates with the slot 201.

[0025] The coolant in the annular coolant flow passage 421 flows into the coolant flow passage 202 of the core block 200D, and then passes through the coolant flow passage 203 of the core block 200C and flows into the slots 201. The coolant moves through the gaps in the slots 201 in the slot axial direction (towards both ends in the figure) and flows out from the coil end direction. Thus, in the first modification, the coolant not only flows through the core blocks 200A and 200B, but is also introduced into the slots 201 and directly cools the stator coils 21. As a result, the cooling efficiency can be further improved.

[0026] However, when a coolant flow passage is formed in the stator core, the magnetic flux density distribution changes, and the torque decreases compared to when there is no coolant flow passage. FIG. 11 is a diagram showing an example of the magnetic flux density distribution when no coolant flow passage is provided. FIG. 11 shows a part of the rotor 3 and the stator 2, and the lines indicated by the reference numeral 500 are lines representing the magnetic flux density (hereinafter, referred to as magnetic flux lines). The number of magnetic flux lines per unit volume represents the magnitude of the magnetic flux density, and the magnetic flux density is represented by the degree of concentration of the magnetic flux lines and the direction in which the magnetic flux lines flow. In the example shown in FIG. 11, it can be seen from the number of magnetic flux lines that the magnetic flux density in region F1 is greater than the magnetic flux density in region F2.

[0027] On the other hand, Fig. 12 is a comparative example of magnetic flux density distribution (distribution of magnetic flux lines) when a refrigerant flow passage is formed as a comparative example of this embodiment. Figs. 13 and 14 show core blocks 300A and 300B constituting the stator core 20 in the comparative example shown in Fig. 12. In the core block 300A, a plurality of refrigerant flow passages 202 are formed at a pitch θ. The circumferential positions of the refrigerant flow passages 202 are the same as the slots 201. In the core block 300B, a plurality of refrigerant flow passages 203 communicating with the slots 201 are formed at a pitch θ. When the core blocks 300A and 300B are stacked, the inner peripheral end region of the refrigerant flow passage 202 faces the outer peripheral end region of the refrigerant flow passage 203, and the refrigerant flow passages 202 and 203 communicate with each other.

[0028] Fig. 12(a) shows the magnetic flux density distribution in the core block 300A, and Fig. 12(b) shows the magnetic flux density distribution in the core block 300B. In the core block 300A, the flow of magnetic flux lines is hindered by the coolant flow passages 202 extending in the radial direction, and magnetic flux lines are hardly seen in the region indicated by the symbol F3 of the back yoke (the core part on the outer circumferential side of the slots 201). As a result, the torque reduction effect is large.

[0029] Fig. 15 shows the magnetic flux density distribution when the core blocks 200C, 200D shown in Figs. 8, 9 are used in this embodiment. Since the core blocks 200C, 200D have the same shape, the magnetic flux density distribution is also the same. As shown in Fig. 9, in the case of the core blocks 200C, 200D, the coolant flow paths 202 provided on the outer periphery side of the back yoke and the coolant flow paths 203 provided on the inner periphery side are alternately arranged in the circumferential direction at a pitch θ. Therefore, compared to the comparative example (Fig. 12), the magnetic flux lines are distributed over the entire back yoke, and the torque decrease is suppressed compared to the comparative example.

[0030] In addition, in the core blocks 200A and 200B, a magnetic flux density distribution similar to that in the core blocks 200C and 200D is formed, and torque reduction can be suppressed. In the core block 210 shown in Fig. 6, only the coolant flow passages 204 provided in the vicinity of the slots 201 are formed, so that torque reduction can be further suppressed compared to the core blocks 200A and 200B.

[0031] As shown in Fig. 8, the inner peripheral end region of the coolant flow passage 202 and the outer peripheral end region of the coolant flow passage 203 of the core blocks 200C and 200D face each other in a first region E1 (see Fig. 9). The radial position of this facing first region E1 is represented by a deviation amount Δ based on the radial center position of the back yoke. If the core outer diameter is R1 and the distance from the stator axis to the bottom of the slot 201 is R2, the radial center position of the back yoke is (R1+R2) / 2. When the facing region (first region E1) is at the radial center position of the back yoke, Δ=0, and when it is located on the outer periphery side of the radial center position, Δ>0.

[0032] Fig. 16 is a diagram showing the torque improvement rate based on the comparative example. The dashed line L1 indicates the comparative example, and the solid line L2 indicates the case where the core blocks 200C and 200D shown in Figs. 8 and 9 are used. Fig. 16 shows the torque improvement rate based on the comparative example when Δ=0. As shown by line L1, in the comparative example, the torque reduction is smallest (0%) when Δ=0, and it can be seen that the torque improvement rate becomes a negative value as the first region E1, which is the opposing region, approaches the inner circumference and the outer circumference from Δ=0, and the torque is further reduced.

[0033] 8 and 9 (solid line L2), the torque improvement rate is largest when Δ=0, and decreases as the opposing region approaches the inner circumference and the outer circumference from Δ=0. However, the torque improvement rate is a positive value regardless of whether the deviation amount Δ is positive or negative.

[0034] As described above, in the first embodiment, by forming the refrigerant flow paths 202-204 in the core blocks 200A, 200B and the core blocks 200C, 200D of the stator core 20, it is possible to suppress torque reduction due to the influence of the refrigerant flow paths while improving the cooling performance of the stator core 20 and the stator coil 21. In addition, as shown in Figs. 2, 6 and 7, by providing the stator core 20 with the core block 210 in which only the flow path 204 is formed, it is possible to further suppress torque reduction.

[0035] Second embodiment Figures 17 to 19 are diagrams showing core blocks 200E, 200F in the second embodiment. Figure 17 is a front view of the core blocks 200E, 200F in a stacked state. Figures 18 and 19 are front views of each core block 200E, 200F. In Figure 17, the core block 200E is disposed on the front side of the figure, and the core block 200F is disposed behind it (the negative z-axis side).

[0036] As shown in FIG. 18, the core block 200E includes a refrigerant flow path 203 extending in the radial direction, a refrigerant flow path 204 extending in the axial direction, and a refrigerant flow path 205 extending in the circumferential direction. Furthermore, one of the multiple refrigerant flow paths 205 (refrigerant flow path 205-1) is provided with a refrigerant introduction path 206 extending in the radial direction and communicating the core outer periphery side with the refrigerant flow path 205. The 18 slots 201 are provided with a pitch θ. That is, θ=20°. Three refrigerant flow paths 205 extending in the circumferential direction are provided in the first region E1. The refrigerant flow path 205 extends over an angle 3θ, and the three refrigerant flow paths 205 are arranged in the circumferential direction with a pitch 3θ.

[0037] In each region between the three refrigerant flow paths 205, three refrigerant flow paths 203 are provided at a pitch θ. The refrigerant flow paths 203 extend from an annular first region E1 to an annular second region E2 (see FIG. 4) on the radially inner side, similar to the refrigerant flow path 203 shown in FIG. 4. A group of three refrigerant flow paths 203 arranged at a pitch θ is provided at a pitch 4θ in the circumferential direction, and three refrigerant flow paths 204 are arranged at a pitch θ between the groups. The multiple refrigerant flow paths 204 are arranged in the annular second region E2, similar to the refrigerant flow path 204 shown in FIG. 4.

[0038] 19, the coolant introduction passage 206 is not provided in the coolant flow passage 205-1. The core block 200F is rotated clockwise by an angle 3θ with respect to the core block 200E. The other configurations are the same as those of the core block 200E.

[0039] The core blocks 200E, 200F of Figures 18 and 19 are stacked as shown in Figure 17. Both circumferential end regions of the coolant flow passage 205 of the core block 200E are arranged to overlap one end of the coolant flow passage 205 adjacent in the circumferential direction provided in the core block 200F. As a result, the coolant flow passage 205 of the core block 200E communicates with the coolant flow passage 205 of the core block 200F, forming an annular flow passage.

[0040] Moreover, the coolant flow path 205 of the core block 200E faces the outer peripheral end region of the coolant flow path 203 of the core block 200F, and the inner peripheral end region of the coolant flow path 203 of the core block 200F faces the coolant flow path 204 of the core block 200E. Similarly, the coolant flow path 205 of the core block 200F faces the outer peripheral end region of the coolant flow path 203 of the core block 200E, and the inner peripheral end region of the coolant flow path 203 of the core block 200E faces the coolant flow path 204 of the core block 200F.

[0041] Fig. 20 is a cross-sectional view taken along the line D3-D3 in Fig. 17. Although Fig. 17 does not show the core block 210 and the stator coil 21 in the slot 201, Fig. 8 also shows the core block 210 and the stator coil 21. The outer peripheral end region of the coolant flow path 203 of the core block 200F faces the coolant flow path 205 of the core block 200E. The inner peripheral end region of the coolant flow path 203 of the core block 200F faces the coolant flow path 204 of the core block 200E and the core block 210 on the right side in the figure. Also, the coolant flow path 204 of the core block 200E faces the coolant flow path 204 of the core block 210 on the left side in the figure.

[0042] The arrows in Fig. 20 indicate the flow of the coolant. The coolant is supplied to the coolant flow path 205 of the core block 200E from the coolant inlet path 206 shown in Fig. 17. The coolant inlet path 206 is connected to an annular coolant flow path 421 formed on the inner periphery of the case 4 (see Fig. 1). The coolant in the coolant flow path 421 flows from the coolant inlet path 206 of the core block 200E into the coolant flow path 205. The coolant that flows into the coolant flow path 205 passes through the coolant flow paths 203 and 204 and flows out from the end face of the core block 210 in the coil end direction.

[0043] (Variation 2) 21 to 23 are diagrams showing a modified example (modified example 2) of the above-mentioned core blocks 200E, 200F. In modified example 2, the stator core 20 is composed of core blocks 200G, 200H and two core blocks 210. FIG. 21 is a diagram showing a laminate of core blocks 200G, 200H as viewed from the front. Core block 200G is disposed on the front side of the figure, and core block 200H is disposed behind it (z-axis negative side). FIG. 22 is a front view of core block 200G. FIG. 23 is a front view of core block 200H.

[0044] 22, core block 200G includes coolant flow passages 203 extending in the radial direction and communicating with slots 201, coolant flow passages 205 extending in the circumferential direction, and coolant introduction passages 206 extending in the radial direction and communicating the core outer periphery side with coolant flow passage 205. Compared to core block 200E shown in FIG. 18, the circumferential positions of coolant flow passages 203, 205 of core block 200G are shifted clockwise by an angle θ / 2, and the circumferential position of coolant flow passage 203 coincides with the circumferential position of slot 201.

[0045] Fig. 23 is a front view of core block 200H. Core block 200H is obtained by removing coolant introduction passage 206 from core block 200G and rotating the entire core block by angle 3θ clockwise about the stator axis. By stacking core block 200G of Fig. 22 on this core block 200H, the core block stacked body shown in Fig. 21 is obtained.

[0046] As shown in Fig. 21, both circumferential end regions of the coolant flow passage 205 of the core block 200G are arranged to overlap one end of the coolant flow passage 205 adjacent in the circumferential direction provided in the core block 200H. As a result, the coolant flow passage 205 of the core block 200G communicates with the coolant flow passage 205 of the core block 200H to form an annular flow passage. In addition, the coolant flow passage 205 of the core block 200G faces the outer peripheral end region of the coolant flow passage 203 of the core block 200H. Similarly, the coolant flow passage 205 of the core block 200H shown by the dashed line faces the outer peripheral end region of the coolant flow passage 203 of the core block 200G.

[0047] 17, three refrigerant flow paths 203, refrigerant flow paths 205, and three refrigerant flow paths 204 are alternately arranged at a pitch of 3θ. Therefore, all of the refrigerant flow paths 204 can be connected to the refrigerant flow paths 205 via the refrigerant flow paths 203 simply by stacking the core block 200F with the core block 200E shifted by the angle 3θ.

[0048] On the other hand, when the refrigerant flow paths 205, five refrigerant flow paths 204, and one refrigerant flow path 203 are arranged alternately as in the core block 200J shown in Fig. 24, five rotations are required to connect all the refrigerant flow paths 204 to the refrigerant flow path 205 via the refrigerant flow paths 203. That is, six core blocks 200J shown in Fig. 24 must be prepared, and the core blocks 200J must be stacked while being shifted by the angle θ each time. Therefore, in the case of a configuration in which the refrigerant flow paths 205 extending in the circumferential direction are provided, it is preferable to alternately arrange the circumferential flow paths (refrigerant flow paths 205) and the radial flow paths (refrigerant flow paths 203) at an equal pitch as in Figs. 17 and 21.

[0049] 8 and 9, for example, in the core block of the first embodiment, a refrigerant flow passage 202 extending in the radial direction is provided on the outer periphery side of the back yoke, and the refrigerant from the outside is guided to a refrigerant flow passage 203 provided in the inner region of the back yoke via the refrigerant flow passage 202. Meanwhile, in the second embodiment, a refrigerant flow passage 205 extending in the circumferential direction is provided on the outer periphery side of the back yoke, and the refrigerant is guided to the refrigerant flow passage 203 in the inner region, thereby suppressing torque reduction caused by the refrigerant flow passage.

[0050] Fig. 25 is a diagram showing the torque improvement rate similar to that in Fig. 16, and shows the case of Δ=0 in a comparative example (when no refrigerant flow path is provided) as a reference (0%). In Fig. 25, line L3 shown by a solid line shows the torque improvement rate when core blocks 200G and 200H are used. Line L4 shown by a dashed dotted line shows the torque improvement rate when refrigerant flow paths 203 and 205 are alternately arranged at a pitch θ as in core block 200K shown in Fig. 26.

[0051] Fig. 27 is a diagram showing the magnetic flux density distribution when core blocks 200G, 200H shown in Figs. 21 to 23 are used. Fig. 28 is a diagram showing the magnetic flux density distribution when core block 200K is used. By alternately arranging coolant flow paths 203 and coolant flow paths 205, the magnetic flux density distribution is improved, and as shown in Fig. 25, the torque is improved compared to the comparative example.

[0052] In a configuration in which the refrigerant channels 202, 203 extending in the radial direction are alternately arranged as in the core blocks 200C, 200D shown in Fig. 8, 9, the torque improvement is maximum when the connection position of the refrigerant channels 202, 203 is at the center of the width direction of the back yoke (Δ=0) as shown in Fig. 16. On the other hand, in a configuration in which the refrigerant channels 205 extending in the circumferential direction and the refrigerant channels 203 extending in the radial direction are alternately arranged as in the second embodiment, the torque improvement increases as the connection position of the refrigerant channels 203, 205 approaches the inner periphery of the back yoke as shown in Fig. 25. From the change tendency of the lines L3, L4 in Fig. 25, it is preferable to set the connection position (first region E1) of the refrigerant channels 203, 205 on the inner periphery side from the center of the back yoke.

[0053] (Third embodiment) 29 to 34 are diagrams for explaining the third embodiment. In the above-mentioned first and second embodiments, for example, the stator 2 is fixed to the inner periphery of the case 4 as shown in FIGS. 1 and 2. In the third embodiment, as shown in FIG. 29, each of the core blocks 410A, 400A, 400B, and 410B provided in the stator core 20 has a fastening portion 409 protruding from the outer periphery of the stator core 20 (i.e., the core blocks 410A, 400A, 400B, and 410B). The fastening portion 409 has a fastening hole 408 formed therein as described later. Then, the stator 2 is fixed to a stator fixing portion 412 on the case side by inserting a bolt 420 into each fastening hole 408 of the core blocks 410A, 400A, 400B, and 410B.

[0054] FIG. 30 is a front view of a laminated body of core blocks 400A and 400B. FIG. 31 is a front view of core block 400A. FIG. 32 is a front view of core block 400B. FIG. 33 is a front view of core block 410A. As shown in FIG. 31, core block 400A has refrigerant flow paths 203, 204, 205, and 206 similar to those of core block 200E shown in FIG. 18. Core block 400A further has three fastening portions 209 described above at a pitch of 120°. Each fastening portion 409 has fastening hole 408 described above. In addition, one of fastening portions 409 has refrigerant supply hole 207 formed therein, and one of refrigerant flow paths 206 is connected to refrigerant supply hole 207.

[0055] As shown in Fig. 32, the core block 400B is provided with coolant flow paths 203, 204, and 205 similar to those of the core block 200F shown in Fig. 19. The core blocks 400A and 400B of Figs. 31 and 32 are stacked as shown in Fig. 30. Both circumferential end regions of the coolant flow path 205 of the stacked core block 400A are arranged to face one end of the coolant flow path 205 adjacent in the circumferential direction provided in the core block 400B. As a result, the coolant flow path 205 of the core block 400A communicates with the coolant flow path 205 of the core block 400B, forming an annular flow path.

[0056] Also, the coolant flow path 205 of the core block 400A is connected to the outer peripheral end region of the coolant flow path 203 of the core block 400B, and the inner peripheral end region of the coolant flow path 203 of the core block 400B is connected to the coolant flow path 204 of the core block 400A. Similarly, the coolant flow path 205 of the core block 400B is connected to the outer peripheral end region of the coolant flow path 203 of the core block 400A, and the inner peripheral end region of the coolant flow path 203 of the core block 400A is connected to the coolant flow path 204 of the core block 400B.

[0057] As shown in Fig. 33, the core block 410A has a refrigerant flow path 204 formed therein, similar to that of the core block 210 shown in Fig. 6. Furthermore, each fastening portion 409 has a refrigerant supply hole 207 and a fastening hole 408 formed therein. Although not shown, the core block 410B has a configuration in which the refrigerant supply hole 207 is removed from the core block 410A.

[0058] Fig. 34 is a cross-sectional view taken along D4-D4 in Fig. 30. Note that while Fig. 30 does not show core blocks 410A, 410B and stator coils 21 in slots 201, Fig. 34 also shows core blocks 410A, 410B and stator coils 21. A refrigerant introduction hole 412a for introducing a refrigerant from the outside is formed in stator fixing part 412 to which stator core 20 is fixed, at a position facing refrigerant supply hole 207 of core block 410A.

[0059] The coolant introduced through coolant inlet hole 412a of stator fixing portion 412 flows from coolant supply hole 207 of core block 410A to coolant supply hole 207 of core block 400A. The coolant that has flowed into coolant supply hole 207 of core block 400A flows into coolant flow path 205 via coolant flow path 206 that communicates with coolant supply hole 207. Coolant flow path 205 faces the outer circumferential end region of coolant flow path 203 of core block 400B, and the coolant in coolant flow path 205 flows into coolant flow path 203.

[0060] The inner peripheral end region of the coolant flow path 203 of the core block 400B faces the coolant flow paths 204 of the core blocks 400A and 410B. Therefore, the coolant in the coolant flow path 203 flows through the coolant flow path 204 of the core block 410B to the right in the figure, and is discharged from the core end to the coil end. On the other hand, the coolant that flows from the coolant flow path 203 of the core block 400B to the coolant flow path 204 of the core block 400A flows through each of the coolant flow paths 204 of the core blocks 400A and 410A to the left in the figure, and is discharged from the core end to the coil end.

[0061] As described above, the stator core 20 in the third embodiment is configured such that the fastening portion 409 provided on the outer periphery side of the core block is fixed to the stator fixing portion 412 on the case side. In a rotating electric machine configured in this manner, similarly to the second embodiment, the refrigerant flow paths extending in the circumferential direction and the refrigerant flow paths extending in the radial direction are alternately arranged at equal pitches in the circumferential direction, thereby improving the cooling performance by providing the refrigerant flow paths and suppressing the torque reduction due to the influence of the refrigerant flow paths.

[0062] In addition, in a configuration including fastening portion 409, it is possible to introduce the coolant into stator core 20 from the end face of fastening portion 409 using coolant introduction hole 412a of stator fixing portion 412. In this case, by arranging coolant supply hole 207 in the vicinity of fastening hole 408, it is possible to improve sealing performance by fastening to the case with a bolt. In addition, the effect of coolant supply hole 207 on torque reduction can be eliminated.

[0063] The effects of the above-described embodiment and modified examples can be summarized as follows.

[0064] (1) As shown in FIGS. 1 to 6 etc., a rotating electric machine 1 is a rotating electric machine including a rotor 3 and a stator 2 including a plurality of slots 201. A stator core 20 of the stator 2 includes first and second core blocks 200A, 200B stacked in an axial direction. Each of the core blocks 200A, 200B is alternately arranged at a predetermined angular pitch θ in the circumferential direction of the stator and includes a plurality of refrigerant flow paths (first flow paths) 202 and refrigerant flow paths (second flow paths) 203 extending in the radial direction of the stator. The refrigerant flow paths 202 are connected to a refrigerant passage 203 through which a refrigerant is supplied from the outside. and extends from the core outer periphery to a first region (predetermined radial region) E1 on the radially inner side, and the refrigerant flow path 203 extends from the first region E1 to a second region (region near the slot) E2 on the radially inner side, and core blocks 200A and 200B are stacked in the axial direction so that the inner end region of the refrigerant flow path 202 of core block 200A is connected to the outer end region of the refrigerant flow path 203 of core block 200B and the inner end region of the refrigerant flow path 202 of core block 200B is connected to the outer end region of the refrigerant flow path 203 of core block 200A.

[0065] As described above, in each of the core blocks 200A and 200B, the multiple refrigerant flow paths 202 and 203 extending in the stator radial direction are alternately arranged at a predetermined angular pitch θ in the stator circumferential direction. The multiple refrigerant flow paths 202 extend from the outer periphery of the back yoke to the first region E1, and the multiple refrigerant flow paths 203 extend from the first region E1 to the second region E2, which is a region near the slots. As a result, it is possible to improve the cooling efficiency by the refrigerant while suppressing torque reduction.

[0066] (2) In the above (1), as shown in Figures 3, 4, 16, etc., it is preferable that the inner peripheral end region of coolant flow passage 202 and the outer peripheral end region of coolant flow passage 203, which communicate with each other, are located approximately midway (i.e., Δ=0) between the outer peripheral end of slot 201 and the outer periphery of stator core 20. By setting them in this way, the torque improvement rate can be maximized as shown in Figure 16, that is, the torque reduction due to the influence of the coolant flow passages can be suppressed to a smaller extent.

[0067] (3) As shown in Figs. 1, 17 to 25, etc., a rotating electric machine 1 is a rotating electric machine including a rotor 3 and a stator 2 having a plurality of slots 201. A stator core 20 of the stator 2 has first and second core blocks 200E, 200F stacked in the axial direction. Each of the core blocks 200E, 200F communicates with a plurality of refrigerant flow paths (first flow paths) 205 and a refrigerant flow path (second flow path) 203 that are alternately arranged at a pitch (predetermined angular pitch) 3θ in the circumferential direction of the stator. The refrigerant flow paths 205 communicate with any one of the plurality of refrigerant flow paths 205, and a refrigerant flow path (second flow path) 203 is supplied from the outside. The core blocks 200E and 200F are stacked in the axial direction such that the coolant flow path 205 of the core block 200E is connected to the outer circumferential end region of the coolant flow path 203 of the core block 200F and the coolant flow path 205 of the core block 200F is connected to the outer circumferential end region of the coolant flow path 203 of the core block 200E.

[0068] As described above, by alternately arranging the refrigerant flow passages 205, which extend in the stator circumferential direction, and the refrigerant flow passages 203, which are provided closer to the core inner circumference than the refrigerant flow passages 205 and extend in the radial direction, at a predetermined angular pitch in the stator circumferential direction, it is possible to improve the cooling efficiency by the refrigerant while suppressing torque reduction.

[0069] (4) In the above (3), as shown in Figures 21 to 25, it is preferable that the first region E1 is located closer to the core inner circumference than the approximate middle (i.e., Δ=0) between the outer circumferential end of the slot 201 and the outer periphery of the stator core 20. By setting it in this way, it is possible to increase the torque improvement rate as shown in Figure 25, that is, to minimize the torque reduction caused by the influence of the coolant flow path.

[0070] (5) In the above (1) or (3), as shown in Figures 3 to 5, each of core blocks 200A, 200B further includes a plurality of refrigerant flow paths (third flow paths) 204 that are provided in second region E2 and penetrate in the core axis direction, and refrigerant flow paths 204 of core block 200A communicate with the inner circumferential end region of refrigerant flow path 203 of core block 200B, and refrigerant flow path 204 of core block 200B communicates with the inner circumferential end region of refrigerant flow path 203 of core block 200A. The refrigerant flowing through refrigerant flow paths 204 in the vicinity of the slots can improve the cooling efficiency of stator coils 21 in slots 201.

[0071] 2, 6, 7, etc., the stator core 20 further includes a third core block 210 having a plurality of coolant flow paths (fourth flow paths) 204 at each of the axial ends of the stacked core blocks 200A, 200B, and the coolant flow paths 204 penetrate the core block 210 in the axial direction and communicate with the coolant flow paths 203 of the adjacent core block 200A or core block 200B. By including the core block 210 in the stator core 20, the torque reduction can be further suppressed.

[0072] (7) In the above (1) or (3), as shown in Figures 8, 9, etc., it is preferable that the refrigerant flow passage 203 penetrates from the second region E2 of the slot vicinity region further to the slot 201. By the refrigerant flowing from the refrigerant flow passage 203 into the slot 201, the stator coil 21 can be directly cooled by the refrigerant, and the cooling efficiency of the stator coil 21 can be improved.

[0073] (8) In the above (3), as shown in Figures 17 to 19, when integer N is an integer equal to or greater than 2, it is preferable that the slots 201 are arranged at an angular pitch θ in the stator circumferential direction, the predetermined angular pitch is set to a value N times the angular pitch θ, and the refrigerant flow paths 203 arranged between the refrigerant flow paths 205 are composed of N flow paths extending in the radial direction and arranged at the angular pitch θ in the stator circumferential direction. By configuring in this manner, it is possible to form refrigerant flow paths that communicate with each other by a single rotation.

[0074] (9) In the above (3), as shown in Figures 29 to 34 etc., stator core 20 includes a plurality of fastening portions 409 protruding from the outer periphery of the core and having fastening holes (bolt insertion holes) 408 formed therein, and at least one of the plurality of fastening portions 409 preferably has a refrigerant supply hole (introduction hole) 207 formed near fastening hole 408, through which a refrigerant is introduced from the outside and which communicates with refrigerant flow path 205. By arranging refrigerant supply hole 207 near fastening hole 408, the effect of refrigerant supply hole 207 on torque reduction is eliminated, and sealing performance is improved by bolt fastening.

[0075] The various embodiments and modifications described above are merely examples, and the present invention is not limited to these unless the characteristics of the invention are lost. Other embodiments that are conceivable within the scope of the technical idea of ​​the present invention are also included in the scope of the present invention. [Explanation of symbols]

[0076] Reference Signs List 1... rotating machine, 2... stator, 3... rotor, 4... case, 20... stator core, 21... stator coil, 200A to 200K, 210, 400A, 400B, 410A, 410B... core block, 201... slot, 202 to 205, 421... refrigerant flow path, 206... refrigerant introduction path, 207... refrigerant supply hole, 408... fastening hole, 409... fastening portion, 412... stator fixing portion, 420... through hole, E1... first region, E2... second region

Claims

1. A rotating electric machine including a rotor and a stator including a plurality of slots, The stator core of the stator has first and second core blocks stacked in the axial direction, Each of the first and second core blocks includes a plurality of first and second flow passages that are alternately arranged at a predetermined angular pitch in the stator circumferential direction and extend in the stator radial direction, The first flow passage is supplied with a refrigerant from an outside and extends from an outer periphery of the core to a predetermined radial region on a radially inner periphery side, The second flow passage extends from the predetermined radial region to a region adjacent to the slot on the radially inner circumferential side, a rotating electric machine, characterized in that the first and second core blocks are stacked in the axial direction such that an inner circumferential end region of the first flow path of the first core block is connected to an outer circumferential end region of the second flow path of the second core block, and such that an inner circumferential end region of the first flow path of the second core block is connected to an outer circumferential end region of the second flow path of the first core block.

2. 2. The rotating electric machine according to claim 1, A rotating electric machine, characterized in that the inner end region of the first flow passage and the outer end region of the second flow passage, which are connected to each other, are located approximately halfway between the outer end of the slot and the outer periphery of the stator core.

3. A rotating electric machine including a rotor and a stator including a plurality of slots, The stator core of the stator has first and second core blocks stacked in the axial direction, Each of the first and second core blocks comprises: a plurality of first and second flow paths alternately arranged at a predetermined angular pitch in the circumferential direction of the stator; an introduction passage communicating with any one of the plurality of first flow passages and supplying a refrigerant from an outside; The first flow passage extends in a circumferential direction of the stator in a predetermined radial region, The second flow passage extends from the predetermined radial region to a region adjacent to the slot on the radially inner circumferential side, A rotating electric machine characterized in that the first and second core blocks are stacked in the axial direction so that the first flow path of the first core block communicates with an outer peripheral end region of the second flow path of the second core block, and so that the first flow path of the second core block communicates with an outer peripheral end region of the second flow path of the first core block.

4. 4. The rotating electric machine according to claim 3, The rotating electric machine, characterized in that the predetermined radial direction region is located on the inner periphery side of the core from approximately the middle between the outer periphery end of the slot and the outer periphery of the stator core.

5. 4. The rotating electric machine according to claim 1, Each of the first and second core blocks further includes a plurality of third flow passages provided in the slot vicinity region and penetrating therethrough in the core axial direction, the third flow passage of the first core block communicates with an inner peripheral end region of the second flow passage of the second core block, a third flow passage of the second core block communicating with an inner peripheral end region of the second flow passage of the first core block,

6. 6. The rotating electric machine according to claim 5, the stator core further includes a third core block having a plurality of fourth flow passages at both axial ends of the stacked first and second core blocks, a fourth flow passage passing through the third core block in the axial direction and communicating with the third flow passage of an adjacent first or second core block,

7. 4. The rotating electric machine according to claim 1, The rotating electric machine, wherein the second flow passage extends from the region adjacent to the slot to the slot.

8. 4. The rotating electric machine according to claim 3, When the integer N is an integer of 2 or more, The slots are arranged at a first angular pitch in the circumferential direction of the stator, the predetermined angular pitch is set to a value N times the first angular pitch, A rotating electric machine, characterized in that the second flow passages arranged between the first flow passages are composed of N flow passages extending in a radial direction and arranged at the first angular pitch in a stator circumferential direction.

9. 4. The rotating electric machine according to claim 3, The stator core includes a plurality of fastening portions protruding from an outer periphery of the core and each having a bolt insertion hole formed therein, a first passage for introducing a refrigerant from the outside and for communicating with the first flow passage, the first passage being formed in the vicinity of the bolt insertion hole in at least one of the fastening portions.

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