Winding field-type rotary electric machine

Abstract

To effectively cool field winding, etc., by liquid refrigerant in a configuration in which an axial end part of the field winding is covered with resin.SOLUTION: A winding field-type rotary electric machine includes: a stator; a rotor; and a coolant passage communicated to a pump which pumps liquid refrigerant. A stator coil includes a coil end part protruding in an axial direction from an axial end face of the stator core. The axial end part of field winding protrudes in the axial direction from the axial end face of the rotor core and is covered with a resin part. The rotor includes a cover member for covering the axial end part of the field winding and formed of a material whose thermal conductivity is higher than the resin part. At an outer end face of the cover member in the axial direction, liquid refrigerant is supplied through the coolant passage.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] There is known a technique for injecting liquid refrigerant from the axial outside toward the axial end portion of the field winding (the portion protruding in the axial direction from the end face of the rotor core). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 095842 Brochure Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a configuration in which the axial end of the field winding is covered with resin, it is not possible to directly supply oil (liquid refrigerant) to the field winding, making it difficult to effectively cool the field winding with oil supplied to the axial end face of the rotor.

[0005] Therefore, in one aspect, an object of the present disclosure is to effectively cool the field winding and the like with a liquid refrigerant in a configuration in which an axial end of the field winding is covered with resin. [Means for solving the problem]

[0006] In one aspect, a stator having a stator core and a stator coil; a rotor including a shaft portion, a rotor core coaxially fixed to the shaft portion, and a field winding wound around teeth of the rotor core, the rotor being disposed coaxially with the stator and with a gap provided in the radial direction; a refrigerant flow path communicating with a pump that pumps a liquid refrigerant; The stator coil includes a coil end portion protruding in the axial direction from an axial end surface of the stator core, an axial end portion of the field winding protrudes in the axial direction from an axial end face of the rotor core and is covered by a resin portion, the rotor further includes a cover member covering an axial end of the field winding, the cover member being made of a material having a higher thermal conductivity than the resin portion, The liquid refrigerant is supplied to the axially outer end face of the cover member through the refrigerant flow path, thereby providing a wound-field type rotating electric machine. Effect of the Invention

[0007] According to one aspect of the present disclosure, in a configuration in which an axial end of a field winding is covered with resin, the field winding and the like can be effectively cooled by a liquid refrigerant. [Brief description of the drawings]

[0008] [Figure 1] 1 is a configuration diagram showing a vehicle drive system including a drive device for a rotating electric machine according to an embodiment of the present invention; [Diagram 2] 2 is a schematic cross-sectional view showing a part of a cross section of a rotating electric machine; [Diagram 3] 3 is a schematic cross-sectional view showing a part of the cross section of the rotating electric machine (a cross section taken along line AA in FIG. 2). [Figure 4] FIG. 2 is a cross-sectional view of the rotor in a single component state. [Diagram 5] 3 is a schematic cross-sectional view showing an axial end (a circumferential position not passing through the teeth) of the rotor corresponding to a portion Q2 in FIG. 2. FIG. [Figure 6] 4 is a schematic cross-sectional view showing an axial end portion of a rotor according to a comparative example. [Figure 7] 11A to 11C are diagrams illustrating the flow of oil at an inclined portion of an axial end surface of a cover member according to the present embodiment. [Figure 8] 13 is a diagram illustrating a schematic view of the flow of oil on an axial end face of a cover member according to a comparative example. FIG. [Figure 9]4 is a schematic cross-sectional view of an axial end of a rotor at a circumferential position that does not pass through a teeth portion. FIG. [Figure 10] 6A to 6C are diagrams illustrating the flow of oil in a recess in an axial end surface of the cover member according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Each embodiment will be described in detail below with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are merely examples and are not intended to be limiting, and shapes and the like in the drawings may be partially exaggerated for the sake of explanation.

[0010] FIG. 1 is a configuration diagram showing a vehicle drive system 1 including a drive device 5 for a rotating electric machine according to this embodiment. FIG. 2 is a schematic cross-sectional view showing a part of a cross section of a rotating electric machine 3 (a cross section cut along a plane including a rotation axis I). FIG. 3 is a schematic cross-sectional view showing a part of a cross section of a rotating electric machine 3 (a cross section taken along a line AA in FIG. 2). In FIG. 2, an X direction along the rotation axis I of the rotating electric machine 3, and an X1 side and an X2 side are defined. In addition, in FIG. 1 and FIG. 2, a power supply device 7 and a brush 69 (only in FIG. 1) on the rotation side are shown in a schematic manner. In addition, in FIG. 2 (as well as in FIG. 7 and the like described later), a schematic diagram of an oil supply system including an oil supply device 8 is also shown.

[0011] In the following description, the axial direction refers to the direction in which the rotation axis I of the rotating electric machine 3 extends (X direction), and the radial direction refers to the radial direction centered on the rotation axis I. Therefore, the radially outer side refers to the side away from the rotation axis I, and the radially inner side refers to the side toward the rotation axis I. Additionally, the axially outer side refers to the side away from the axial center of the stator 320, and the axially inner side refers to the side approaching the axial center of the stator 320. Additionally, the circumferential direction corresponds to the direction of rotation around the rotation axis I.

[0012] The vehicle drive system 1 has a dual power supply configuration including a low-voltage battery 2A and a high-voltage battery 2B, and includes a rotating electric machine 3 and a drive device 5.

[0013] The low-voltage battery 2A is, for example, a lead battery, and has a rated voltage of, for example, 12V.

[0014] The high-voltage battery 2B is, for example, a lithium-ion battery, and has a rated voltage significantly higher than that of the low-voltage battery 2A, for example, a rated voltage of 40 V or more. In this embodiment, as an example, the rated voltage of the high-voltage battery 2B is 300 V or more. The high-voltage battery 2B may be in the form of a fuel cell or the like.

[0015] The rotating electric machine 3 is of a wound field type equipped with a power supply device 7 on the rotating side and brushes 69 , and includes a rotor 310 and a stator 320 .

[0016] The rotor 310 is disposed radially inside the stator 320, coaxially with the stator 320 with a radial gap therebetween. The rotor 310 has a rotor core 312, end plates 313, a shaft portion 314, a rotor winding 316, and a cover member 318. The rotor core 312 is fixed coaxially to the shaft portion 314. As shown in FIG. 3, the rotor core 312 has teeth portions 3122 that protrude radially outward, and a conductor wire that forms the rotor winding 316 is wound around the teeth portions 3122.

[0017] In this embodiment, axial end portion 3162 of rotor winding 316 protrudes in the axial direction from the axial end face of rotor core 312. As shown in Fig. 2 (see also Fig. 5 described later), axial end portion 3162 of rotor winding 316 protrudes more axially outward than radially inward.

[0018] In this embodiment, the axial end 3162 of the rotor winding 316 is covered with a resin portion 3164. That is, the axial end 3162 of the rotor winding 316 is sealed with an insulating resin material.

[0019] Cover member 318 is formed of a material having higher thermal conductivity than resin portion 3164, and is preferably formed of a material having higher thermal conductivity such as aluminum. Cover member 318 covers axial end 3162 of rotor winding 316 via resin portion 3164. In other words, resin portion 3164 extends between cover member 318 and rotor winding 316. In this case, resin portion 3164 may be formed by injection molding or the like.

[0020] Further details of the configuration of the axial end 311 of the rotor 310, including the cover member 318, will be described below with reference to Figures 4 onwards.

[0021] Stator 320 includes a stator core 321 and a stator winding 322. As shown in Fig. 3, stator winding 322 is wound around teeth 3210 of stator core 321. Note that stator winding 322 has coil end portions 3222 that are portions that protrude axially outward from the axial end face of stator core 321, as shown in Fig. 2.

[0022] The driving device 5 includes a microcomputer 50 (hereinafter referred to as “microcomputer 50”) and an electric circuit section 60.

[0023] The microcomputer 50 may be realized as, for example, an ECU (Electronic Control Unit). The microcomputer 50 is connected to various electronic components (other ECUs and sensors) in the vehicle via a network 6 such as a CAN (Controller Area Network).

[0024] The microcomputer 50 receives various commands such as control commands from a higher-level ECU (not shown) via the network 6. The microcomputer 50 controls the rotating electric machine 3 via the electric circuit unit 60 based on the control commands.

[0025] The electric circuit section 60 includes a smoothing capacitor 62 , a power conversion circuit section 63 , and a power supply circuit section 64 .

[0026] The smoothing capacitor 62 is provided between the high potential side line 20 and the low potential side line 22 of the high voltage battery 2B. Both ends of the smoothing capacitor 62 may be connected to a resistor R0 for passive discharge.

[0027] The power conversion circuit unit 63 is in the form of an inverter, and forms, for example, a three-phase bridge circuit. The power conversion circuit unit 63 is connected between the high potential side line 20 and the low potential side line 22 in a manner that the power conversion circuit unit 63 is in parallel with the smoothing capacitor 62. The power conversion circuit unit 63 includes switching elements SW3 of a high potential side arm and switching elements SW4 of a low potential side arm. In this case, the microcomputer 50 may control the energization of the stator winding 322 by controlling the on / off state of the switching elements SW3, SW4 of the power conversion circuit unit 63 via the gate driver circuit 52.

[0028] The power supply circuit section 64 includes a bridge circuit section 641 and a drive circuit section 642 .

[0029] The bridge circuit section 641 is connected in parallel with the smoothing capacitor 62 and the resistor R0 for passive discharge between the high potential side line 20 and the low potential side line 22. The bridge circuit section 641 includes a pair of switching elements SW1, SW2 and a pair of diodes D1, D2.

[0030] The switching element SW1 is connected in series to the diode D1 in a manner that the switching element SW1 is connected to the cathode on the high potential side of the diode D1. The positive end of the rotor winding 316 is electrically connected between the switching element SW1 and the diode D1 via a positive slip ring 71 and a brush 69, which will be described later. The switching element SW2 is connected in series to the diode D2 in a manner that the switching element SW2 is connected to the anode on the low potential side of the diode D2. The negative end of the rotor winding 316 is electrically connected between the switching element SW2 and the diode D2 via a negative slip ring 72 and a brush 69, which will be described later.

[0031] The pair of switching elements SW1, SW2 are switched between on and off states via the drive circuit unit 642. The pair of switching elements SW1, SW2 change the state of current flow to the rotor winding 316 under the control of the drive circuit unit 642. The switching elements SW1, SW2 are, for example, insulated gate bipolar transistors (IGBTs), but may be of other types such as metal oxide semiconductor field-effect transistors (MOSFETs).

[0032] The drive circuit unit 642 drives the gates of the switching elements SW1 and SW2 based on a control signal from the microcomputer 50.

[0033] Next, with continued reference to FIG. 2, the characteristic configuration of this embodiment will be described with reference to FIG. 4 and subsequent figures.

[0034] Fig. 4 is a cross-sectional view of rotor 310 in a single state, taken along a plane perpendicular to the axial direction. Fig. 5 is a schematic cross-sectional view showing axial end 311 of rotor 310 corresponding to part Q2 in Fig. 2, taken at a circumferential position corresponding to line BB in Fig. 4. Fig. 6 is a schematic cross-sectional view showing an axial end of rotor 310' according to a comparative example, taken at a circumferential position corresponding to Fig. 5.

[0035] In this embodiment, the axial end portion 311 of the rotor 310 includes the axial end portion 3162 of the rotor winding 316, the resin portion 3164, and the cover member 318, as described above.

[0036] An axial end 311 of the rotor 310 is cooled by oil (an example of a "liquid refrigerant"). Specifically, an oil supplying device 8 is provided, and as shown in FIG. 2, the oil supplying device 8 includes an oil pump 80 that pumps oil to the rotating electric machine 3 and the like. The oil pump 80 is supported by a case (not shown) that houses the rotating electric machine 3. The oil pump 80 may be mechanical or electric. The oil supplying device 8 may include a combination of a mechanical oil pump and an electric oil pump. The oil supplying device 8 may include an oil cooler, a strainer, and the like for lowering the temperature of the oil discharged from the oil pump 80.

[0037] In this embodiment, the oil supply device 8 has an oil passage 84 that supplies oil discharged from the oil pump 80 to the axial end 311 of the rotor 310. The oil passage 84 may be formed in a case (not shown), may be formed by a tubular member such as a pipe, or may be realized by a combination of an oil passage in the case and a tubular member. One end of the oil passage 84 communicates with the oil pump 80, and the other end communicates with the peripheral space of the axial end 311 of the rotor 310.

[0038] For example, the oil passage 84 may have an injection hole (not shown) facing the axial direction on the axial outer side of the axial end 311 of the rotor 310 (the axial end surface 3182 of the cover member 318). In this case, the oil may be injected from the injection hole so as to axially strike the axial end 311 of the rotor 310 (the axial end surface 3182 of the cover member 318) by the oil pressure increased by the oil pump 80 (see arrow R20 in FIG. 2). Alternatively, the oil passage 84 may have an injection hole 3143 that communicates with an oil passage (hollow axial oil passage) 3142 in the shaft portion 314 and faces the axial end 311 of the rotor 310 in the radial direction. In this case, the oil may be injected from the injection hole 3143 so as to strike the axial end 311 of the rotor 310 (for example, the axial end surface 3182 of the cover member 318) by centrifugal force (see arrow R22 in FIG. 2). Alternatively, the oil may be injected from the injection hole 3143 slightly axially outward from the axial end 311 of the rotor 310 (the axial end surface 3182 of the cover member 318) by centrifugal force (see FIG. 10 described later). The injection holes 3143 may be provided at a plurality of positions in the circumferential direction. Although FIG. 2 shows the oil passage 84 related to the axial end 311 on the X2 side in the X direction generally as the flow of oil passing therethrough, the same may be true for the oil passage related to the axial end 311 on the X1 side in the X direction.

[0039] In this embodiment, oil is supplied to axial end surface 3182 of cover member 318 facing axially outward (outer surface opposite to inner surface facing axial end 3162 of rotor winding 316) via oil passage 84 as described above, as shown in Fig. 5. This allows axial end 311 of rotor 310 (particularly axial end 3162 of rotor winding 316) to be cooled by oil via cover member 318, which has a relatively high thermal conductivity.

[0040] In this embodiment, since the resin part 3164 is interposed between the cover member 318 and the axial end 3162 of the rotor winding 316, from the viewpoint of increasing the thermal conductivity between the cover member 318 and the axial end 3162 of the rotor winding 316, it is desirable that the axial thickness of the resin part 3164 axially outside the axial end 3162 of the rotor winding 316 (hereinafter also simply referred to as the "axial thickness of the resin part 3164") is smaller.

[0041] In this regard, in the comparative example shown in FIG. 6, the cover member 318' has a planar shape. That is, the cover member 318' has an axial end surface 3182' in a plane perpendicular to the axial direction. In the case of such a cover member 318', due to the shape of the axial end 3162 of the rotor winding 316 (the shape in which the radially outer side protrudes axially outward more than the radially inner side), the axial thickness of the resin part 3164' is likely to be relatively thicker on the radially inner side than on the radially outer side. In this case, a problem occurs in that the thermal resistance between the cover member 318' and the axial end 3162 of the rotor winding 316 becomes relatively large due to the resin part 3164' having a relatively large thickness on the radially inner side.

[0042] In contrast, in this embodiment, the cover member 318 is formed so that the axial thickness of the resin portion 3164 is approximately constant at each radial position. Specifically, in this embodiment, in response to the shape of the axial end portion 3162 of the rotor winding 316 (the shape in which the radially outer side protrudes axially outward more than the radially inner side), the axial end surface 3182 of the cover member 318 includes an inclined portion 31820 that is inclined in such a manner that the radially outer side is located axially outward more than the radially inner side. This makes it possible to minimize the axial thickness of the resin portion 3164 at each radial position, and the axial end portion 3162 of the rotor winding 316 can be efficiently cooled by oil via the cover member 318.

[0043] Furthermore, according to this embodiment, the cover member 318 has the inclined portion 31820, and thus the surface area of ​​the axial end face 3182 of the cover member 318 can be increased compared to the comparative example shown in FIG. 6. That is, the cover member 318 has a cone-shaped configuration, and thus the surface area can be increased compared to the comparative example having a planar shape. As a result, the cooling performance via the axial end face 3182 of the cover member 318 can be improved. Note that the axial outer surface of the inclined portion 31820 (i.e., the axial end face 3182) does not need to be planar, and may be, for example, curved and convex downward.

[0044] Fig. 7 is a diagram showing a schematic diagram of oil flow at inclined portion 31820 of axial end surface 3182 of cover member 318 according to this embodiment. Fig. 8 is a schematic cross-sectional view of a rotating electric machine 3' according to a comparative example, showing a schematic diagram of oil flow at axial end surface 3182' of cover member 318' according to the comparative example.

[0045] In this embodiment and the comparative example, when the rotor 310 rotates, the oil supplied to the axial end face 3182 of the cover member 318 moves radially outward due to centrifugal force (see arrow R70 in FIG. 7 and arrow R80 in FIG. 8). In the comparative example, the oil supplied to the axial end face 3182' of the cover member 318' is unlikely to remain on the axial end face 3182' because the axial end face 3182' is flat and perpendicular to the axial direction, and is likely to splash radially outward or axially outward.

[0046] In contrast, according to this embodiment, although the oil supplied to the axial end surface 3182 of the cover member 318 flows radially outward due to centrifugal force (see arrow R70 in FIG. 7), the flow is likely to be hindered by the inclined portion 31820. For this reason, the oil supplied to the axial end surface 3182 of the cover member 318 is relatively likely to remain on the axial end surface 3182. For example, the oil is likely to remain in the space portion SC70 (space portion radially inward from the inclined portion 31820) which is typically shown by the hatched range in FIG. 7. This makes it possible to improve the cooling performance via the axial end surface 3182 of the cover member 318.

[0047] Here, the oil supplied to the inclined portion 31820 is ultimately scattered radially outward by centrifugal force (see arrow R71 in FIG. 7). In this regard, when the radially outer end portion of the inclined portion 31820 is located axially outward from the axial end surface 3212 of the stator core 321 as in the example shown in FIG. 7, it is difficult to supply the oil flowing radially outward along the inclined portion 31820 to the axial end surface 3212 or the coil end portion 3222 of the stator core 321.

[0048] Therefore, the inclined portion 31820 described above with reference to FIG. 5 and the like may be formed over the entire circumferential circumference, but is preferably formed only within a circumferential range that faces the axial end 3162 of the rotor winding 316 in the axial direction. That is, the axial end face 3182 of the cover member 318 preferably has a different configuration from the inclined portion 31820 in a circumferential range that does not face the axial end 3162 of the rotor winding 316 in the axial direction (hereinafter also referred to as the "circumferential range between the teeth portions 3122"). Specifically, as will be described below with reference to FIG. 9 and FIG. 10, the axial end face 3182 of the cover member 318 has a configuration in which oil flows axially more inward than the inclined portion 31820 in the circumferential range between the teeth portions 3122.

[0049] Fig. 9 is a schematic cross-sectional view showing axial end 311 of rotor 310, and is a cross-sectional view at a circumferential position (a circumferential position corresponding to line CC in Fig. 4) within a circumferential range between teeth 3122. Fig. 10 is a diagram showing a schematic view of oil flow in recess 31822 of axial end face 3182 of cover member 318 according to this embodiment.

[0050] 9, axial end face 3182 of cover member 318 extends axially inward more than inclined portion 31820 in the circumferential range between teeth portions 3122. For this reason, axial end face 3182 of cover member 318 is likely to extend axially inward more than axial end portion 3162 of rotor winding 316 in the circumferential range between teeth portions 3122. As a result, in the circumferential range between teeth portions 3122, oil flowing radially outward along axial end face 3182 of cover member 318 can be easily supplied to axial end face 3212 and coil end portion 3222 of stator core 321.

[0051] 9 in particular, the cover member 318 has, at its radially outer end, a side wall portion 3186 that extends axially outward from an axial end face 3182 of the cover member 318, and the side wall portion 3186 has a radial through hole 31862. This makes it easy to supply oil supplied onto the axial end face 3182 of the cover member 318 to the axial end face 3212 and the coil end portion 3222 of the stator core 321 via the radial through hole 31862 in the circumferential range between the teeth portions 3122.

[0052] The axially outer end of the side wall portion 3186 may be continuous with the radially outer portion of the above-mentioned inclined portion 31820. In this case, the portion that defines the axially outermost position of the cover member 318 may be the radially outer portion of the inclined portion 31820 and the axially outer end of the side wall portion 3186.

[0053] 9, the axial end surface 3182 of the cover member 318 has a recess 31822 recessed axially inward from the through hole 31862 in a circumferential range between the teeth portions 3122. That is, the axial end surface 3182 of the cover member 318 has a recess 31822 recessed axially inward at a circumferential position where the through hole 31862 is formed. In this case, the recess 31822 causes the axial end surface 3182 of the cover member 318 to extend axially inward from the through hole 31862.

[0054] Thus, according to this embodiment, the axial end surface 3182 of the cover member 318 has the recess 31822 radially inward of the through hole 31862 in the circumferential range between the teeth portions 3122. As a result, of the oil flowing over the axial end surface 3182 as described above, the oil within the circumferential range between the teeth portions 3122 can be guided to the through hole 31862 (see arrows R100 and R101 in FIG. 10). For this purpose, when the oil passage 84 has the above-mentioned injection hole 3143, the injection hole 3143 may preferably be provided at the circumferential position where the through hole 31862 is provided.

[0055] Further, according to this embodiment, the through hole 31862 can be formed axially inward by deepening the depth (axial dimension) of the recess 31822 of the axial end surface 3182 of the cover member 318. For example, the through hole 31862 can be formed axially inward from the axial end surface of the axial end portion 3162 of the rotor winding 316. This makes it easy to supply oil through the through hole 31862 toward the axial end surface 3212 and the coil end portion 3222 of the stator core 321 that may be located axially inward from the axial end surface of the axial end portion 3162 of the rotor winding 316 (see arrow R102 in FIG. 10). For this purpose, the through hole 31862 may be formed axially inward within a range located axially outward from the recess 31822. In this case, the axial position of the through hole 31862 can be brought as close as possible to the axial position of the axial end surface 3212 of the stator core 321.

[0056] 9, the radial through-holes 31862 may extend in a direction perpendicular to the axial direction, or may extend in an oblique direction (for example, in an oblique direction in which the radially outer side is the axially inner side). When the radial through-holes 31862 extend in such an oblique direction, even if the axial position of the through-holes 31862 is located axially outer than the axial position of the axial end faces 3212 of the stator core 321, it is easy to direct the oil injected from the through-holes 31862 toward the axial end faces 3212 of the stator core 321.

[0057] In this manner, in this embodiment, the recess 31822 and the through hole 31862 of the cover member 318 function as an oil guide. Specifically, as shown typically by arrows R100, R101, and R102 in Fig. 10, the recess 31822 and the through hole 31862 of the cover member 318 can cause the oil supplied via the oil passage 84 as described above to flow radially outward from the axial end face 3182, and can direct the oil from the radially outer end of the axial end face 3182 toward the axial end face of the stator core 321 or the coil end portion 3222.

[0058] The recesses 31822 and the through holes 31862 are preferably provided in a plurality of pairs, each pair being located between the teeth 3122 of the rotor core 312 in the circumferential direction, as viewed in the axial direction. That is, the recesses 31822 and the through holes 31862 are preferably provided in pairs between the teeth 3122 of the rotor core 312 in the circumferential direction. Note that one or more through holes 31862 may be provided for one recess 31822. In this manner, a plurality of recesses 31822 and through holes 31862 may be provided in a circumferential range between the teeth 3122 (a circumferential range that does not face the axial end 3162 of the rotor winding 316 in the axial direction). This allows oil to be sprayed from the plurality of circumferential through holes 31862 toward the axial end surface or the coil end portion 3222 of the stator core 321, and the cooling performance for the axial end surface or the coil end portion 3222 of the stator core 321 can be effectively improved.

[0059] 9 and 10, part or all of the side wall portion 3186 of the cover member 318 may be omitted in the circumferential range between the teeth portions 3122 of the rotor core 312. In this case, the function of the through hole 31862 can be realized by the missing portion of the side wall portion 3186 (a notch portion that opens axially outward).

[0060] Although each embodiment has been described above in detail, the present invention is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the claims. In addition, it is also possible to combine all or a plurality of the components of the above-described embodiments. [Explanation of symbols]

[0061] 3··· rotating electric machine (wound field type rotating electric machine), 320··· stator, 321··· stator core, 322··· stator winding (stator coil), 3212··· axial end face, 310··· rotor, 312··· rotor core, 3122··· teeth portion, 314··· shaft portion, 316··· rotor winding (field winding), 3162··· axial end portion, 3164··· resin portion, 318··· cover member, 3182··· axial end face (axial outer end face), 31820··· inclined portion, 31822··· recessed portion, 3186··· side wall portion, 31862··· through hole, 84··· oil passage (coolant passage), 80··· oil pump (pump)

Claims

1. a stator having a stator core and a stator coil; a rotor including a shaft portion, a rotor core coaxially fixed to the shaft portion, and a field winding wound around teeth of the rotor core, the rotor being disposed coaxially with the stator and with a gap provided in the radial direction; a refrigerant flow path communicating with a pump that pumps a liquid refrigerant; The stator coil includes a coil end portion protruding in the axial direction from an axial end surface of the stator core, an axial end portion of the field winding protrudes in the axial direction from an axial end face of the rotor core and is covered by a resin portion, the rotor further includes a cover member covering an axial end of the field winding, the cover member being made of a material having a higher thermal conductivity than the resin portion, the liquid refrigerant is supplied to an axially outer end face of the cover member through the refrigerant flow path.

2. 2. The wound-field type rotating electric machine according to claim 1, wherein the axially outer end face of the cover member extends axially inwardly beyond an axial end portion of the field winding between the teeth portions of the rotor core in the circumferential direction when viewed in the axial direction.

3. the cover member includes a side wall portion at a radially outer end portion, the side wall portion extending in the axial direction outward beyond the axially outer end surface of the cover member, The wound field type rotating electric machine according to claim 1 , wherein the side wall portion has a radial through hole.

4. 4. The wound-field rotating electric machine according to claim 3, wherein the end face on the axially outer side of the cover member has a recess that is recessed axially inward from the through hole at a circumferential position where the through hole is formed.

5. 5. The wound-field rotating electric machine according to claim 4, wherein a plurality of sets of the through holes and the recesses are provided and positioned between the teeth of the rotor core in the circumferential direction when viewed in the axial direction.

6. an axial end portion of the field winding is configured to protrude more axially outwardly on the radial outer side than on the radial inner side, 6. The wound field type rotating electric machine according to claim 1, wherein the end face on the axially outer side of the cover member includes an inclined portion that is inclined such that the radially outer side is located axially outer than the radially inner side.

7. 7. The wound-field type rotating electric machine according to claim 6, wherein a radially outer end portion of the inclined portion is located axially outward of an axial end face of the stator core.

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