Rotating Electric Machine

Abstract

The rotating electric machine (101) includes a shaft (13), a rotor (12), a stator (11), end plates (14) fixed to both ends of the rotor (12), bearings (16) supporting the shaft (13), a frame (10) having bearings (16) on both end surfaces and accommodating the stator (11) and the rotor (12), internal fins (15) fixed to the end plates (14), and heat exchangers (21) provided on both end surfaces of the frame (10).

Description

[Technical field]

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

[0002] When the shaft and rotor of a rotating electric machine rotate, the stator and rotor generate heat, and at the same time, heat is generated due to friction in the bearings and heat is generated due to windage loss between the stator and rotor. Thus, the entire rotating electric machine becomes hot when it rotates.

[0003] Therefore, in order to cool the stator and rotor, a structure is known in which internal fins are provided on the end faces of the rotor, and the internal fins agitate the air within the frame as the rotor rotates (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-155720 A Summary of the Invention [Problem to be solved by the invention]

[0005] Rotating electric machines are required to be small and have high output in fields such as FA (Factory Automation) and EV (Electric Vehicles), and high-speed rotation technology for rotating electric machines is essential to achieve small size and high output. When a rotating electric machine rotates at high speed, the amount of heat generated in the stator and rotor, and the amount of heat generated due to friction and windage loss also increase, making it difficult to achieve high speed rotation with the cooling technology of Patent Document 1. To achieve high speed rotation, there are also cooling technologies that use water cooling or oil cooling. However, water cooling or oil cooling requires pumps, valves, etc., which makes it difficult to reduce the size of the rotating electric machine.

[0006] The present disclosure has been made in view of the above, and has an object to obtain a rotating electric machine that has improved cooling performance, is compact, and can rotate at high speed. [Means for solving the problem]

[0007] In order to solve the above problems and achieve the object, the present disclosure provides a rotating electric machine including a shaft, a rotor fixed to the shaft, a stator, and a rotor having a stator and a stator at both ends. The load side of the surface Fixed to Load side An end plate; an end plate on the opposite side that is fixed to one of both end faces of the rotor on the opposite side; A frame that includes a bearing for supporting a shaft and bearings on both end faces and that houses a stator and a rotor; Load side end plate and non-load side End Plates At least one of and a heat exchanger provided on each end surface of the frame. The direction of the rotation axis of the shaft is defined as the axial direction, and the direction perpendicular to the axial direction is defined as the radial direction of the rotor. The heat exchanger faces the fins in the radial direction. In order to solve the above-mentioned problems and achieve the object, the rotating electric machine of the present disclosure includes a shaft, a rotor fixed to the shaft, a stator, a load-side end plate fixed to the load-side end face of both end faces of the rotor, an anti-load-side end plate fixed to the anti-load-side end face of both end faces of the rotor, a bearing supporting the shaft, a frame having bearings on both end faces and accommodating the stator and the rotor, and a fin fixed to the anti-load-side end plate. The axial direction of the rotation axis of the shaft is defined as the axial direction, and the radial direction of the rotor, which is a direction perpendicular to the axial direction, is defined as the radial direction. The frame includes a third ventilation passage provided between the inner side surface of the frame and the outer side surface of the frame, through which inside air flows in the axial direction, and a fourth ventilation passage provided between the inner side surface of the frame and the outer side surface of the frame, through which outside air flows in the axial direction. The inside air and the outside air exchange heat through the frame. The lengths of the third ventilation passage and the fourth ventilation passage in the axial direction are longer than the distance between the load-side end plate and the anti-load side end plate in the axial direction. Effect of the Invention

[0008] The rotating electric machine according to the present disclosure has the advantages of improving cooling performance, achieving miniaturization and high speed rotation. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a first embodiment; [Diagram 2] FIG. 1 is a cross-sectional view showing a configuration of a rotating electric machine according to a first embodiment. [Diagram 3] FIG. 1 is a cross-sectional view showing a configuration of a rotating electric machine according to a first embodiment. [Figure 4] FIG. 11 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a second embodiment. [Diagram 5] FIG. 11 is a cross-sectional view showing the configuration of a rotating electric machine according to a second embodiment. [Figure 6] FIG. 11 is a cross-sectional view showing the configuration of a rotating electric machine according to a second embodiment. [Figure 7] FIG. 11 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a third embodiment. [Figure 8] FIG. 11 is a cross-sectional view showing a configuration of a rotating electric machine according to a third embodiment. [Figure 9] FIG. 11 is a cross-sectional view showing a configuration of a rotating electric machine according to a third embodiment. [Figure 10] FIG. 13 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a fourth embodiment. [Figure 11] FIG. 13 is a cross-sectional view showing the configuration of a rotating electric machine according to a fourth embodiment. [Figure 12] FIG. 13 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a fifth embodiment. [Figure 13] FIG. 13 is a vertical cross-sectional view showing a configuration of a rotating electric machine according to a fifth embodiment. [Figure 14] FIG. 13 is a cross-sectional view showing the configuration of a rotating electric machine according to a fifth embodiment. [Figure 15] FIG. 13 is a vertical sectional view showing a configuration of a rotating electric machine according to a sixth embodiment. [Figure 16] FIG. 13 is a vertical sectional view showing a configuration of a rotating electric machine according to a sixth embodiment. [Figure 17] FIG. 13 is a cross-sectional view showing the configuration of a rotating electric machine according to a sixth embodiment. [Figure 18] FIG. 13 is a vertical sectional view showing the configuration of a rotating electric machine according to a seventh embodiment. [Figure 19] FIG. 13 is a vertical sectional view showing the configuration of a rotating electric machine according to a seventh embodiment. [Figure 20] FIG. 13 is a cross-sectional view showing the configuration of a rotating electric machine according to a seventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a rotating electric machine according to an embodiment will be described in detail with reference to the drawings.

[0011] Embodiment 1 Fig. 1 is a vertical cross-sectional view showing the configuration of a rotating electric machine 101 according to a first embodiment. Fig. 2 is a horizontal cross-sectional view showing the configuration of the rotating electric machine 101 according to the first embodiment. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. Fig. 3 is a horizontal cross-sectional view showing the configuration of the rotating electric machine 101 according to the first embodiment. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1.

[0012] In the rotating electric machine 101, a cylindrical frame 10 houses a stator 11 and a rotor 12. The stator 11 is fixed to the inner side surface of the frame 10. A bearing 16 for holding a shaft 13 is provided on a load side end surface 10a and a non-load side end surface 10b of the frame 10. As shown in FIG. 3, the stator 11 has a coil 19 therein, and a part of the coil 19 is exposed to the outside of the stator 11 as a coil end 18. The shaft 13 is held in a rotatable state by the pair of bearings 16. A load (not shown) is connected to the load side of the shaft 13. The rotor 12 is fixed to the shaft 13 so that the rotation axes are aligned, and an air gap 20 exists between the rotor 12 and the stator 11.

[0013] As shown in FIG. 2, end plates 14 for adjusting the weight balance are fixed to both end faces of the rotor 12. Internal fins 15 are fixed to the outside of the end plates 14. In FIG. 1, the internal fins 15 are provided so as to face both the load side space 41 and the counter-load side space 42, but the internal fins 15 may be provided so as to face only one of the load side space 41 and the counter-load side space 42. The load side space 41 is a space formed by the load side end face 10a of the frame 10, one end face of the rotor 12, one end face of the stator 11, the inner side face of the frame 10, etc. The counter-load side space 42 is a space formed by the counter-load side end face 10b of the frame 10, the other end face of the rotor 12, the end face of the end face of the stator 11, the inner side face of the frame 10, etc.

[0014] The internal fins 15 are provided so as to be integral with the rotor 12 and the end plates 14, and therefore rotate in accordance with the rotation of the rotor 12. The end plates 14 are fixed to the axial end faces of the rotor, and the internal fins 15 are provided on the outer end faces of the end plates 14. That is, in the axial direction of the shaft 13, the end faces of the rotor 12, the end plates 14, and the internal fins 15 are provided with no gap between them.

[0015] The rotation of the internal fins 15, as shown by the arrow K1, stirs the internal air (internal air) in the load side space 41 and the counter-load side space 42, respectively, and the internal air by forced convection can remove heat from the stator 11 and the rotor 12. In order to release the heat removed from the stator 11 and the rotor 12 by the internal air to the outside, in the first embodiment, the heat exchanger 21 is provided on the load side end face 10a and the counter-load side end face 10b of the frame 10. The end face of the frame 10 refers to a face of the frame 10 that is perpendicular to the shaft 13 and holds the bearing 16. The load side end face 10a of the frame 10 refers to an end face of the frame 10 that is located on the load side. The counter-load side end face 10b of the frame 10 refers to an end face of the frame 10 that is located on the counter-load side. The heat exchanger 21 can remove heat from the internal air by forced convection and release the heat to the outside air by forced convection or natural convection.

[0016] In addition, an external fan 17 may be provided in the anti-load side space 42, and the frame 10 may be cooled by forced convection of outside air as shown by arrow K2. The external fan 17 is provided on the outside of the frame 10. The external fan 17 is fixed to the shaft 13, and rotates with the rotation of the rotor 12. By cooling the frame 10 with the rotation of the external fan 17, the heat of the inside air can be efficiently discharged to the outside of the frame 10, and the cooling performance can be improved. In addition, the blade shape and arrangement of the internal fins 15 are not limited to those shown in FIG. 2, and other shapes may be used as long as the inside air can be circulated.

[0017] Thus, according to the first embodiment, the internal air in the frame 10 is agitated by the internal fins 15, and the frame 10 is provided with the heat exchanger 21 for promoting heat exchange between the internal air and the external air. Therefore, the temperature of the internal air can be reduced by the heat exchanger 21, and the temperature of the rotating electric machine 101 can be kept low. In particular, since the internal fins 15 are integrated with the end plates 14 and the rotor 12, a large distance can be secured between the internal fins 15 and the end faces of the frame 10. Therefore, the height of the heat exchanger 21 (the length along the rotation axis direction of the shaft 13) can be increased to the immediate vicinity of the internal fins 15. In addition, since a large distance can be secured between the internal fins 15 and the end faces of the frame 10, the radial length of the heat exchanger 21 can be expanded to the immediate vicinity of the bearings 16. When heat exchanger 21 is viewed in a cross section perpendicular to the rotation axis of shaft 13, the radially inner side of heat exchanger 21 close to the rotation axis extends to a position facing rotor 12 and internal fins 15, and the radially outer side of heat exchanger 21 extends to a position facing stator 11. This allows the entire end face of frame 10 to be used as heat exchanger 21. In this way, because internal fins 15 are integrated with end plate 14 and rotor 12, sufficient space for providing heat exchanger 21 can be secured, making it possible to miniaturize rotating electric machine 101 and improve cooling performance. This allows the rotating electric machine to rotate at high speed.

[0018] Embodiment 2 Fig. 4 is a vertical cross-sectional view showing the configuration of a rotating electric machine 102 according to a second embodiment. Fig. 5 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 102 according to the second embodiment. Fig. 5 is a cross-sectional view taken along line VV in Fig. 4. Fig. 6 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 102 according to the second embodiment. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 4.

[0019] In the rotating electric machine 102 according to the second embodiment, a rotor ventilation passage 22 as a first ventilation passage is added to the configuration of the first embodiment. Also, the internal fins 15 are provided only in the anti-load side space 42. The other configurations are the same as those of the first embodiment, and therefore repeated explanations will be omitted.

[0020] In the second embodiment, the rotor 12 and the end plate 14 are provided with a plurality of rotor ventilation passages 22, which are ventilation passages for the inside air passing through in the direction of the rotation axis. The cross section of the rotor ventilation passages 22 is, for example, circular, as shown in Figs. 5 and 6. This is to reduce the ventilation resistance and increase the flow rate through the rotor ventilation passages 22. However, as long as the inside air can pass through the rotor ventilation passages 22, a cooling effect can be obtained, so the cross section of the rotor ventilation passages 22 may be a polygonal shape such as a rectangle or a square, or an elliptical shape. Desirably, the rotor ventilation passages 22 provided in the rotor 12 are provided as close to the center of the rotor 12 as possible. That is, as shown in Fig. 6, the rotor ventilation passages 22 are provided in a position closer to the shaft 13 than the stator 11 in the radial direction. By providing the rotor ventilation passages 22 in such a position, a large negative pressure can be generated in the internal fins 15, and the amount of circulation of the inside air can be increased.

[0021] As shown in FIG. 4, the internal fins 15 are provided only on the end plate 14 facing the anti-load side space 42. This allows the internal air to flow from the load side space 41 to the anti-load side space 42 along the rotation axis direction in the rotor ventilation passage 22 as shown by the arrow K3, and the internal air can circulate to flow through the air gap 20 and back to the load side space 41 as shown by the arrow K4. The internal air flows through the air gap 20 from the anti-load side space 42 to the load side space 41, while the external air flows from the load side space 41 to the anti-load side space 42 by the external fan 17. In this way, by providing the internal fins 15 on the end plate 14 of the anti-load side space 42, the internal air and the external air flow in opposing directions, improving the cooling performance.

[0022] By circulating the inside air in this manner, the inside air and the rotor 12 come into contact with each other at the rotor ventilation passage 22 and the air gap 20, so that the heat transfer area between the inside air and the rotor 12 is increased, and it is possible to efficiently remove heat from the rotor 12. Furthermore, since the rotor ventilation passage 22 rotates together with the rotor 12, the inside of the rotor ventilation passage 22 becomes turbulent, and the heat transfer coefficient between the inside air and the rotor 12 increases. Similarly, the inside air in the air gap 20 also flows in the circumferential direction as the rotor 12 rotates, becoming turbulent, and the heat transfer coefficient increases. Furthermore, since the inside air flowing through the air gap 20 comes into contact with the stator 11, it can also remove heat from the stator 11. The heat removed by the inside air from the rotor 12 and the stator 11 can be efficiently released to the outside air by the heat exchanger 21.

[0023] Thus, according to embodiment 2, the rotor 12 and the end plates 14 are provided with a plurality of rotor ventilation passages 22 penetrating in the direction of the rotation axis, so that internal air flows and circulates through the rotor ventilation passages 22 and the air gap 20, making it possible to efficiently cool the entire rotating electric machine 102, thereby realizing a small-sized rotating electric machine capable of high-speed rotation.

[0024] 4, the internal fins 15 are provided on the end plate of the counter-load side space 42, but if it is difficult to provide the internal fins 15 on the end plate 14 of the counter-load side space 42, the internal fins 15 may be provided on the end plate 14 of the load side space 41 as long as the internal air can flow so as to circulate through the rotor ventilation passage 22 and the air gap 20. Furthermore, the internal fins 15 may be provided in both the counter-load side space 42 and the load side space 41 as long as the internal air can flow so as to circulate through the rotor ventilation passage 22 and the air gap 20.

[0025] Embodiment 3 FIG. 7 is a vertical cross-sectional view showing the configuration of a rotating electric machine 103 according to a third embodiment. FIG. 8 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 103 according to a third embodiment. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7 and shows a first specific example. FIG. 9 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 103 according to a third embodiment. FIG. 9 is a cross-sectional view taken along line VIII-VIII in FIG. 7 and shows a second specific example.

[0026] In a rotating electric machine 103 according to the third embodiment, a stator ventilation passage 23 as a second ventilation passage is added to the configuration of the first embodiment. Also, internal fins 15 are provided only in the anti-load side space 42. The other configurations are the same as those of the first embodiment, and therefore repeated explanations will be omitted.

[0027] In the third embodiment, a plurality of stator ventilation passages 23, which are ventilation passages for internal air passing through in the direction of the rotation axis, are provided in stator 11. Stator ventilation passages 23 may be provided on the outer diameter side of coil 19 as shown in Fig. 8, or may be provided on the outer periphery of stator 11 as shown in Fig. 9, but are preferably provided radially outward of coil 19.

[0028] As with rotor ventilation passage 22 in the second embodiment, the cross-sectional shape of stator ventilation passage 23 is preferably circular as shown in Fig. 8 in order to reduce ventilation resistance and increase the circulation flow rate. However, as long as internal air can pass through stator ventilation passage 23, the cross-sectional shape of stator ventilation passage 23 may be a polygonal shape such as a rectangle or a square, or an elliptical shape. Furthermore, when stator ventilation passage 23 is provided at the outermost circumference in the radial direction of stator 11 as shown in Fig. 9, the cross-sectional shape of stator ventilation passage 23 is preferably semicircular, rectangular, or square.

[0029] As shown in FIG. 7, the internal fins 15 are provided on the end plate 14 of the counter-load side space 42. When the internal fins 15 rotate, the internal air flows through the air gap 20 from the load side space 41 toward the counter-load side space 42 along the axial direction as shown by the arrow K5, and the internal air can circulate to flow through the stator ventilation passage 23 to the load side space 41 again as shown by the arrow K6. When the internal air flows through the air gap 20, it can take heat from the rotor 12. The heat taken by the internal air is efficiently released to the outside air by the heat exchanger 21 provided on the end face of the frame 10, so that the rotating electric machine 103 can cool the rotor 12 more efficiently than the rotating electric machine 101. Furthermore, when the internal air flows through the stator ventilation passage 23, the internal air flows in a direction opposite to the outside air (arrow K2) flowing around the frame 10 by the external fan 17, so that the outside air can efficiently take heat from the stator 11 and the internal air.

[0030] As described above, according to the third embodiment, the stator 11 is provided with a plurality of stator ventilation passages 23 penetrating in the direction of the rotation axis, so that internal air circulates through the stator ventilation passages 23 and the air gap 20, and the entire rotating electric machine 103 can be efficiently cooled, thereby realizing a small-sized rotating electric machine capable of high-speed rotation. As in the second embodiment, the internal fins 15 may be provided in the load side space 41, or may be provided in both the anti-load side space 42 and the load side space 41.

[0031] Embodiment 4 Fig. 10 is a vertical cross-sectional view showing the configuration of a rotating electric machine 104 according to a fourth embodiment. Fig. 11 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 104 according to a fourth embodiment. Fig. 11 is a schematic cross-sectional view taken along line XI-XI in Fig. 10, showing a first specific example.

[0032] The rotating electric machine 104 according to the fourth embodiment is a combination of the rotating electric machine 102 according to the second embodiment and the rotating electric machine 103 according to the third embodiment. That is, the rotating electric machine 104 adds a rotor ventilation passage 22 and a stator ventilation passage 23 to the configuration of the first embodiment. Also, the internal fins 15 are provided only in the anti-load side space 42. The other configurations are the same as those of the first embodiment, and a duplicated description will be omitted. In the fourth embodiment, the rotor 12 and the end plate 14 are provided with a plurality of rotor ventilation passages 22 which are ventilation passages for internal air passing through in the direction of the rotation axis, and the stator 11 is provided with a plurality of stator ventilation passages 23 which are ventilation passages for internal air passing through in the direction of the rotation axis.

[0033] The cross-sectional area of ​​each rotor ventilation passage 22 is larger than that of the air gap 20. Also, the cross-sectional area of ​​each stator ventilation passage 23 is larger than that of the air gap 20. As a result, most of the internal air stirred by the internal fins 15 does not pass through the air gap 20 but flows through the stator ventilation passage 23 and the rotor ventilation passage 22, so that the pressure loss when the internal air circulates is reduced. Therefore, the amount of internal air circulated by the internal fins 15 provided on the end plate 14 can be increased, and the cooling performance is improved. Also, since the internal air flows through the rotor ventilation passage 22 and the stator ventilation passage 23, the contact area of ​​the internal air with the rotor 12 and the stator 11 is increased, so that the internal air can efficiently remove heat from the rotor 12 and the stator 11. The heat removed by the internal air from the rotor 12 and the stator 11 is released to the outside air by the heat exchanger 21 provided on the end face of the frame 10.

[0034] Like the rotating electric machines 102 and 103, the rotating electric machine 104 has internal fins 15 provided on the end plate 14 of the anti-load side space 42. The inside air circulates so as to flow through the stator ventilation passage 23 from the anti-load side space 42 to the load side space 41 as shown by arrow K7, and to flow through the rotor ventilation passage 22 from the load side space 41 to the anti-load side space 42 as shown by arrow K8. The inside air flowing through the stator ventilation passage 23 flows in a direction opposite to the outside air flowing around the frame 10 by the external fan 17, so that the outside air can efficiently remove heat from the stator 11 and the inside air.

[0035] In the second and third embodiments, the inside air flows through the air gap 20. However, since the size of the air gap is small, when the inside air flows through the air gap 20, the pressure loss increases, and the volume of the inside air circulating in the frame 10 decreases. Therefore, as in the rotating electric machine 104 according to the fourth embodiment, the rotor ventilation passage 22 and the stator ventilation passage 23 are provided, so that the inside air flows through the rotor ventilation passage 22 and the stator ventilation passage 23, and the pressure loss can be reduced compared to the second and third embodiments. Therefore, in the rotating electric machine 104, the volume of air generated by the internal fins 15 can be increased, so that the heat transfer coefficient between the inside air and the rotor 12 and the stator 11 can be increased, and the rotor 12 and the stator 11 can be efficiently cooled.

[0036] Thus, according to the fourth embodiment, rotor 12 is provided with rotor ventilation passage 22, and stator 11 is provided with stator ventilation passage 23, so that the internal air can be circulated so as to flow through rotor ventilation passage 22 and stator ventilation passage 23. Therefore, the entire rotating electric machine 104 can be efficiently cooled, and a small rotating electric machine capable of high speed rotation can be realized. Note that internal fins 15 may be provided in load side space 41, or may be provided in both anti-load side space 42 and load side space 41.

[0037] Embodiment 5. Fig. 12 is a vertical cross-sectional view showing the configuration of a rotating electric machine 105 according to a fifth embodiment. Fig. 13 is a vertical cross-sectional view showing the configuration of a rotating electric machine 105 according to a fifth embodiment. Fig. 13 is cut along a vertical cross section different from that of Fig. 12. Fig. 14 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 105 according to a fifth embodiment. Fig. 14 is a cross-sectional view cut along line XIV-XIV in Fig. 12, as viewed from the direction of arrow H.

[0038] In the fifth embodiment, the heat exchanger 21 is eliminated from the configuration of the first embodiment. In the fifth embodiment, the frame 10 is provided with an in-frame ventilation passage 240 including a plurality of in-frame ventilation passages 241 for inside air and a plurality of in-frame ventilation passages 242 for outside air, and the in-frame ventilation passage 240 plays the role of the heat exchanger 21 of the first embodiment. The in-frame ventilation passage 241 for inside air corresponds to the third ventilation passage, and the in-frame ventilation passage 242 for outside air corresponds to the fourth ventilation passage. In addition, as shown in FIG. 13, an in-frame ventilation hole 243 is also provided as an inlet and outlet of the in-frame ventilation passage 241 for inside air. In addition, the internal fin 15 is provided only in the anti-load side space 42. The other configurations are the same as those of the first embodiment, and a duplicated description will be omitted. In FIG. 13, the dashed circle indicates that outside air passes through, and the solid circle indicates that inside air passes through. An x in a circle represents a flow from the load side space 41 to the anti-load side space 42, and a black circle in a circle represents a flow from the anti-load side space 42 to the load side space 41.

[0039] The number of the outside air in-frame ventilation passages 242 is equal to or greater than the number of the inside air in-frame ventilation passages 241. The outside air not only needs to exchange heat with the inside air, but also needs to remove heat transmitted from the stator 11 to the frame 10 by thermal conduction, so the number of the outside air in-frame ventilation passages 242 is equal to or greater than the number of the inside air in-frame ventilation passages 241. The total cross-sectional area of ​​the outside air in-frame ventilation passages 242 needs to be equal to or greater than the cross-sectional area of ​​the inside air in-frame ventilation passages 241. Preferably, the inside air in-frame ventilation passages 241 and the outside air in-frame ventilation passages 242 are arranged in an alternating manner, as shown in FIG. 14. By arranging them in an alternating manner, the area available for heat exchange between the inside air and the outside air is increased, allowing for efficient heat exchange.

[0040] 13, there are also provided interior air vents 243 as entrances and exits of the interior air frame ventilation passage 241. The interior air vents 243 are provided on the cylindrical surface of the frame 10 as shown in FIG. 13, and one interior air vent 243 is provided in each of the load side space 41 and the anti-load side space 42 for one interior air frame ventilation passage 241. The interior air vent 243 on the load side space 41 side and the interior air vent 243 on the anti-load side space 42 side are both provided in positions as close as possible to the end face of the frame 10.

[0041] 12 and 13, the internal fins 15 are provided on the end plate 14 of the anti-load side space 42, and the inside air circulates by flowing from the load side space 41 to the anti-load side space 42 through the air gap 20 as shown by arrow F1, and then flowing from the anti-load side space 42 to the load side space 41 through the inside air frame ventilation passage 241 as shown by arrow F2. On the other hand, the outside air flows from the load side space 41 to the anti-load side space 42 through the outside air frame ventilation passage 242 by the rotation of the external fan 17 as shown by arrow F3. At this time, the inside air and the outside air flow in opposite directions, so that active heat exchange can be performed through the frame 10.

[0042] The internal air that has flowed into the internal air frame ventilation passage 241 by the internal fins 15 flows along the rotation axis direction from the anti-load side space 42 toward the load side space 41, and then continues to circulate by passing through the air gap 20 and returning to the anti-load side space 42. Because the internal air flows through the air gap 20 once, it is able to remove heat from the rotor 12 and the stator 11. The internal air that has removed the heat can release the heat to the outside air by flowing through the internal air frame ventilation passage 241, and the internal air, now at a low temperature, can flow through the air gap 20 again and cool the rotor 12 and the stator 11.

[0043] Thus, according to the fifth embodiment, the entire frame 10 is configured to be used as a heat exchanger between the inside air and the outside air, improving the cooling performance and realizing a small-sized rotating electric machine capable of high-speed rotation. Also, since there is no need to provide a heat exchanger 21 separate from the frame 10 as in the first to fourth embodiments, the rotating electric machine can be made even smaller. The internal fins 15 may be provided in the load side space 41, or may be provided in both the anti-load side space 42 and the load side space 41.

[0044] Embodiment 6 Fig. 15 is a vertical cross-sectional view showing the configuration of a rotating electric machine 106 according to a sixth embodiment. Fig. 16 is a vertical cross-sectional view showing the configuration of a rotating electric machine 106 according to a sixth embodiment. Fig. 16 is cut along a vertical cross section different from that of Fig. 15. Fig. 17 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 106 according to a sixth embodiment. Fig. 17 is a cross-sectional view cut along line XVII-XVII in Fig. 15, as viewed from the direction of arrow J. In Fig. 17, the meanings represented by the dashed circle, the solid circle, the x in the circle, and the black circle in the circle are the same as those in Fig. 13.

[0045] A rotating electric machine 106 according to the sixth embodiment is a combination of the rotating electric machine 102 according to the second embodiment and the rotating electric machine 105 according to the fifth embodiment. Like the rotating electric machine 105, the rotating electric machine 106 includes a frame 10 having an inside air frame ventilation passage 241, an outside air frame ventilation passage 242, and inside air ventilation holes 243 so that the entire frame 10 functions as a heat exchanger. Also, like the rotating electric machine 102 according to the second embodiment, the rotating electric machine 106 includes a plurality of rotor ventilation passages 22, which are ventilation passages for inside air passing through the rotor 12 and the end plate 14 in the direction of the rotation axis.

[0046] The cross-sectional area of ​​each rotor ventilation passage 22 is larger than that of the air gap 20. With this structure, the internal air stirred by the internal fins 15 does not flow through the air gap 20, but circulates through the internal air frame internal ventilation passage 241 and the rotor ventilation passage 22 as shown by arrows F2 and K3, enabling efficient cooling. In addition, since the cross-sectional area of ​​the rotor ventilation passage 22 is larger than that of the air gap 20, the pressure loss during circulation of the internal air can be reduced and the circulation flow rate of the internal air can be increased, thereby improving cooling performance.

[0047] The number of outside air in-frame ventilation passages 242 is equal to or greater than the number of inside air in-frame ventilation passages 241, as in the fifth embodiment. This allows the outside air to not only exchange heat with the inside air, but also to remove heat from the stator 11, thereby efficiently cooling the entire rotating electric machine 106. Note that, as in the second embodiment, the internal fins 15 may be provided in the load side space 41, or may be provided in both the anti-load side space 42 and the load side space 41.

[0048] Embodiment 7 FIG. 18 is a vertical cross-sectional view showing the configuration of a rotating electric machine 107 according to the seventh embodiment. FIG. 19 is a vertical cross-sectional view showing the configuration of a rotating electric machine 107 according to the seventh embodiment. FIG. 19 is cut along a vertical cross section different from that of FIG. 18. FIG. 20 is a horizontal cross-sectional view showing the configuration of a rotating electric machine 107 according to the seventh embodiment. FIG. 20 is a cross-sectional view cut along the line XX-XX in FIG. 18, as seen from the direction of the arrow L. In FIG. 20, the dashed circle, the solid circle, the x in the circle, and the black circle in the circle have the same meanings as in FIG. 13.

[0049] The rotating electric machine 107 according to the seventh embodiment is a combination of the rotating electric machine 103 according to the third embodiment and the rotating electric machine 105 according to the fifth embodiment. Like the rotating electric machine 105, the rotating electric machine 107 includes a frame 10 having an inside air frame ventilation passage 241, an outside air frame ventilation passage 242, and inside air ventilation holes 243 so that the entire frame 10 functions as a heat exchanger. Also, like the rotating electric machine 103 according to the third embodiment, the rotating electric machine 107 includes a stator 11 provided with a plurality of stator ventilation passages 23 which are ventilation passages for inside air passing through in the direction of the rotation axis.

[0050] The stator ventilation passage 23 is disposed radially outward of the coil 19 so as to avoid the coil 19. The cross-sectional area of ​​each of the stator ventilation passages 23 is larger than the cross-sectional area of ​​the air gap 20. With this structure, the inside air stirred by the internal fins 15 circulates through the inside air frame internal ventilation passage 241 and the stator ventilation passage 23 as shown by the arrows F2 and F4, and can be cooled more efficiently than the rotating electric machine 105 that flows through the air gap 20. Since the cross-sectional area of ​​the stator ventilation passage 23 is larger than the cross-sectional area of ​​the air gap 20, the pressure loss when the inside air circulates can be reduced and the circulation flow rate of the inside air can be increased, so that the cooling performance can be improved. As in the second embodiment, the internal fins 15 may be provided in the load side space 41, or may be provided in both the anti-load side space 42 and the load side space 41.

[0051] The configurations shown in the above embodiments are examples of the contents of the present disclosure, and may be combined with other known technologies, and parts of the configurations may be omitted or modified without departing from the gist of the present disclosure. [Explanation of symbols]

[0052] 10 frame, 10a load side end face, 10b anti-load side end face, 11 stator, 12 rotor, 13 shaft, 14 end plate, 15 internal fin, 16 bearing, 17 external fan, 18 coil end, 19 coil, 20 air gap, 21 heat exchanger, 22 rotor ventilation passage, 23 stator ventilation passage, 41 load side space, 42 anti-load side space, 101, 102, 103, 104, 105, 106, 107 rotating electric machine, 240 frame internal ventilation passage, 241 frame internal ventilation passage for internal air, 242 frame internal ventilation passage for external air, 243 internal air ventilation hole.

Claims

1. A shaft, A rotor fixed to the shaft; A stator; end plates fixed to both ends of the rotor; A bearing for supporting the shaft; a frame having the bearings on both end surfaces and accommodating the stator and the rotor; A fin fixed to the end plate; and a heat exchanger provided on both end surfaces of the frame. A rotating electric machine characterized by:

2. A shaft, A rotor fixed to the shaft; A stator; end plates fixed to both ends of the rotor; A bearing for supporting the shaft; a frame having the bearings on both end surfaces and accommodating the stator and the rotor; A fin fixed to the end plate on the anti-load side; Equipped with The frame is a third ventilation passage provided between an inner side surface of the frame and an outer side surface of the frame, through which internal air flows in a direction of a rotation axis of the shaft; a fourth ventilation passage provided between an inner side surface of the frame and an outer side surface of the frame, through which outside air flows in a direction of a rotation axis of the shaft; In this embodiment, heat exchange between the inside air and the outside air occurs through the frame. A rotating electric machine characterized by:

3. The rotor and the end plate are provided with a plurality of first ventilation passages extending therethrough in the axial direction.

3. The rotating electric machine according to claim 1 or 2.

4. The stator has a plurality of second ventilation passages extending therethrough in the axial direction.

3. The rotating electric machine according to claim 1 or 2.

5. The first ventilation passages are provided at positions closer to the rotation axis of the rotor than the center position of the rotor in the radial direction.

4. The rotating electric machine according to claim 3.

6. The stator includes a coil, and the second ventilation passages are provided radially outward from the coil.

5. The rotating electric machine according to claim 4.

7. A cross-sectional area of ​​each of the first ventilation passages is larger than a cross-sectional area of ​​an air gap between the stator and the rotor.

4. The rotating electric machine according to claim 3.

8. A cross-sectional area of ​​each of the second ventilation passages is larger than a cross-sectional area of ​​an air gap between the stator and the rotor.

5. The rotating electric machine according to claim 4.

9. The frame further includes an external fan fixed to the shaft and provided outside the frame to cool the frame.

3. The rotating electric machine according to claim 1 or 2.

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