JP5409462B2 - Electric motor - Google Patents

Description

  The present invention relates to an electric motor that operates by electromagnetic force, and more particularly to an electric motor that is cooled by being supplied with lubricating oil or a cooling liquid.

  In an electric motor that operates by electromagnetic force, the temperature of the motor rises and the coercive force of the magnet decreases due to the heat generated by the power loss of the motor or the heat from the outside of the motor. To prevent or suppress the temperature rise.

  Patent Document 1 describes a rotating electrical machine in which a refrigerant passage is formed inside a rotating shaft of a rotating electrical machine, and refrigerant is supplied from the refrigerant passage toward a rotor. Patent Document 2 describes a lubricating oil of a composite emulsion for an internal combustion engine or an external combustion engine. Furthermore, Patent Document 3 describes an oil supply device that scoops up oil. And in order to isolate | separate the lubricating oil for cooling, and the refrigerant | coolant for cooling, in patent document 4, heat is applied to the composite liquid with which the lubricating oil and refrigerant | coolant from which boiling point temperature differs differ, and a refrigerant | coolant is evaporated. A device for separating lubricating oil and refrigerant is described. Patent Document 5 forcibly swirls a composite liquid supplied to a high-pressure chamber with an oil separator to generate centrifugal force, and the centrifugal force generates a specific gravity. An apparatus for separating different lubricants and refrigerants is described.

JP 2009-118712 A Japanese Patent Application Laid-Open No. 64-62399 JP 2003-336729 A JP-A-5-141346 JP 2009-196556 A

  In the rotating electrical machine described in Patent Document 1, since the rotor and the end plate provided integrally with the rotating shaft rotate, the refrigerant is supplied from the rotating shaft to the rotor and the stator. it can. However, the rotating electrical machine described in Patent Document 1 is an apparatus intended only for cooling the rotating electrical machine. For example, when the rotating shaft is connected to another member, the other member is also lubricated. Necessary. Therefore, it is necessary to supply the refrigerant and the lubricating oil to the inside of the rotating shaft. Of the composite liquid containing the refrigerant and the lubricating oil, many refrigerants are more effective for cooling the rotating electrical machine. It is not configured for use. The devices described in Patent Document 4 and Patent Document 5 can both separate a composite liquid in which lubricating oil and refrigerant are mixed. However, in the apparatus of Patent Document 4, another apparatus for heating the composite liquid is provided, and in the apparatus of Patent Document 5, an oil separator is provided, so that the configuration of the entire apparatus is complicated and increased in size. there's a possibility that.

  This invention pays attention to the technical problem mentioned above, separates and supplies the mixed liquid by utilizing the centrifugal force by the rotating member, thereby effectively cooling and lubricating, and as a whole apparatus. The purpose is to simplify.

  In order to achieve the above object, an invention according to claim 1 is directed to an electric motor in which a rotor is rotatably disposed on an inner peripheral side of a stator, and lubricates the rotor or a rotating body that rotates integrally with the rotor. A flow path is formed through which a mixed liquid in which oil and a cooling liquid having a lower viscosity than the lubricating oil and a density different from that of the lubricating oil are mixed is passed through the flow path. Among the mixed liquid separated by the centrifugal force by the rotating body, a cooling flow path is provided for sending the cooling liquid to the stator through the rotor.

  According to a second aspect of the present invention, in the first aspect of the invention, the rotor includes an end plate provided with a laminated steel plate constituting the rotor sandwiched in an axial direction, and the cooling flow path is formed on the end plate. The electric motor further includes a through hole formed on the laminated steel plate side and communicating with the cooling channel and the opposite side across the end plate.

  According to a third aspect of the present invention, in the first aspect of the invention, the rotor includes an end plate provided with the laminated steel plates constituting the rotor sandwiched in the axial direction, and gaps are formed on both side surfaces in the axial direction of the end plate. And a stationary plate that is provided in contact with both side surfaces in the axial direction of the stator and is further provided with discharges that penetrate the stationary plate on the outer peripheral side and the inner peripheral side of the stationary plate, respectively. The electric motor is characterized in that a hole is formed.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the rotating body includes a rotating shaft having the rotor provided on an outer periphery, and the flow path is formed by making the rotating shaft hollow. And the inner surface of the flow path located on the outer peripheral side of the rotary shaft is inclined in the axial direction of the rotary shaft from the upstream side to the downstream side of the flow path. .

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the mixed liquid includes a cooling liquid having a density lower than that of the lubricating oil, and the lubricating oil is disposed on a side surface on an outer peripheral side of the rotor. Is an electric motor characterized by being super-oil-repellent treated with no affinity and strong affinity with the cooling liquid.

  According to the first aspect of the present invention, the lubricating oil and the cooling liquid having a lower viscosity than the lubricating oil and a different density from the lubricating oil are mixed in the rotor or the rotating body that rotates integrally with the rotor. Since the flow path through which the mixed liquid is circulated is formed, the lubricating oil and the cooling liquid can be separated by the centrifugal force generated by the rotation of the rotor and the rotating body. Further, since the cooling flow path for sending the separated cooling liquid to the stator through the rotor is provided, the cooling liquid flows through the cooling flow path, so that the rotor or the stator can be cooled. .

  According to the invention of claim 2, in addition to the invention of claim 1, the rotor includes an end plate provided across the laminated steel plates constituting the rotor, and a cooling flow formed on the laminated steel plate side of the end plate. Since the through hole communicating with the path and the opposite side across the end plate is further provided, the mixed liquid, the cooling liquid or the lubricating oil supplied to the rotor can be discharged from the through hole. Therefore, the retention of the liquid in the rotor can be suppressed or prevented, so that the cooling performance of the rotor can be improved.

  According to the invention of claim 3, in addition to the invention of claim 1, the rotor includes an end plate provided with a laminated steel plate constituting the rotor interposed therebetween, and a gap is formed on both side surfaces in the axial direction of the end plate. And a stationary plate provided in contact with both side surfaces in the axial direction of the stator, and through holes are provided on the inner peripheral side and the outer peripheral side of the stationary plate, respectively. Of the lubricating oil and cooling liquid separated by the rotation of the body, the liquid with the higher density can be discharged from the discharge hole on the outer peripheral side, and the liquid with the lower density can be discharged from the discharge hole on the inner peripheral side. Moreover, since each liquid can be discharged | emitted from a rotor, the retention of the liquid in a rotor can be suppressed or prevented and the cooling performance of a rotor can be improved.

  According to the invention of claim 4, in addition to the invention of any one of claims 1 to 3, the rotating body includes a rotating shaft provided with a rotor on the outer peripheral side, and the flow formed by hollowing the rotating shaft. The inner surface located on the outer peripheral side of the rotary shaft in the path is inclined in the axial direction of the rotary shaft from the upstream side to the downstream side of the flow path. Therefore, especially on the upstream side of the flow path, centrifugal force tends to act on the liquid flowing through the flow path, so that high-density liquid is likely to be distributed on the outer peripheral side. Therefore, if a discharge hole for discharging the liquid from the rotating shaft is provided on the upstream side of the flow path, the liquid separated largely on the outer peripheral side can be discharged. That is, the liquid in the flow path and the discharged liquid can be separated and taken out.

  According to the invention of claim 5, in addition to the inventions of claims 1 to 4, the mixed liquid includes a cooling liquid having a density lower than that of the lubricating oil, and the outer peripheral side surface of the rotor has an affinity for the lubricating oil. In addition, the super-oil-repellent treatment has a strong affinity with the cooling liquid, so even if a small amount of lubricating oil is contained in the cooling liquid supplied by separation by centrifugal force, the outer peripheral side of the rotor Since the cooling liquid can be adsorbed on the side surfaces of the rotor, the cooling performance on the outer peripheral side of the rotor that tends to generate heat can be improved.

It is sectional drawing which shows the 1st structural example of the electric motor which concerns on this invention. It is a figure which shows the heat generating part of the electric motor which concerns on this invention. It is a graph which shows the heat-conduction performance of each liquid. It is sectional drawing which shows the 2nd structural example of the electric motor which concerns on this invention. It is a graph which shows the difference of the drag loss of the cooling liquid and lubricating oil. It is sectional drawing which shows the 3rd structural example of the electric motor which concerns on this invention. It is the side view. It is sectional drawing which shows the other shape of the rotating shaft of the electric motor which concerns on this invention. It is the side view. It is a skeleton figure which shows the power transmission mechanism of the vehicle which can mount the electric motor which concerns on this invention. It is a figure which shows the flow of the oil in the power transmission mechanism.

  First, the mixed liquid that can be used in the present invention will be described. The mixed liquid that can be used in the present invention is a mixture of lubricating oil and cooling liquid. There is a large difference in surface tension between the lubricating oil and the cooling liquid. For example, when a mixed liquid obtained by stirring the lubricating oil and the cooling liquid is put in a container and left for a certain period of time, the lubricating oil And the cooling liquid are separated. The cooling liquid is a highly thermally conductive liquid having a lower viscosity and a higher density than the lubricating oil. An example of the cooling liquid is a fluorine-based refrigerant such as fluorinate. In other words, if this mixed liquid is stirred and left for a certain period of time and kept stationary, the cooling liquid density is higher than the lubricating oil density, so that the cooling liquid is distributed downward and the lubricating oil is upward. Many are distributed.

  Next, an example of the electric motor according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a first configuration example. The electric motor 1 is cooled by the cooling liquid. First, the structure of the electric motor 1 will be described. The rotating shaft 3 having a hollow center of rotation and forming the first flow path 2, the rotor 4 provided on the outer periphery of the rotating shaft 3, and the rotor 4 It comprises a stator 5 provided in a case (not shown) with a gap on the outer peripheral side.

  The rotor 4 is provided in order to suppress or prevent the magnetic steel sheet from being separated from the core part 4a formed by laminating the annular electromagnetic steel sheets in the axial direction and the both side surfaces of the core part 4a in the axial direction by magnetic force. The end plate 4b and a permanent magnet 4c provided on the outer peripheral side of the core portion 4a. Therefore, when the rotating shaft 3 rotates, the core part 4a, the end plate 4b, and the permanent magnet 4c rotate integrally. Further, a groove, i.e., a groove extending from the rotation shaft 3 to the stator 5 or from the rotation center side to the outer periphery of the end plate 4b is provided on the core portion 4a side of the end plate 4b in order to distribute a mixed liquid or a cooling liquid described later. Two flow paths 6 are formed.

  Further, a coil (not shown) is wound around the stator 5, and an electromagnetic force is generated by passing a current through the coil. That is, the configuration is such that torque is generated in the rotor 4 by changing the magnetic field by changing the current flowing through the coil. Therefore, the outer periphery of the stator 5 and the rotor 4, that is, the permanent magnet 4c, and the outer periphery of the core portion 4a are caused by the electrical resistance due to the coil and drag loss due to the liquid supplied between the stator 5 and the rotor 4. The side generates heat. FIG. 2 shows the heat generating portion.

  Still further, the first flow path 2 is provided with a supply hole 7 from the first flow path 2 toward the outer peripheral side at a location that coincides with the second flow path 6 formed in the end plate 4b. Yes. That is, when the mixed liquid is flowed from the left to the right of the first flow path 2 in the drawing, the mixed liquid flows through the supply hole 7 into the second flow path 6 and the first flow path 2 as it is. The flow branches to the right side in the figure. That is, the flow branches into two flows, the electric motor 1 and the rotary shaft 3.

  When the mixed liquid is supplied to the electric motor 1, that is, when the mixed liquid is supplied from the left in the drawing of the first flow path 2, when the rotating shaft 3 is not rotating or is rotating at a low rotational speed The mixed liquid passes through the supply hole 7 in a state where the lubricating oil and the cooling liquid are mixed, that is, in a state where they are not separated, and a slit or spline (not shown) provided in the second flow path 6 and the rotor 4. Etc., and supplied between electromagnetic steel sheets. In this case, since the rotation speed of the rotating shaft 3 is low, the heat generation at the outer peripheral side of the rotor 4 and the stator 5 is low, and there is almost no need for cooling. Therefore, the cooling performance to the extent that the mixed liquid flows is sufficient, but when the rotating shaft 3 rotates at a high rotational speed, the heat generation at the outer peripheral side of the rotor 4 and the stator 5 is high, so it is necessary to improve the cooling performance. is there. Therefore, in the present invention, when the rotating shaft 3 is rotating at a high rotational speed, the liquid mixture is separated and the liquid mainly containing a large amount of cooling liquid (hereinafter simply referred to as “cooling liquid”). It is configured to supply the heat generating portion.

  Hereinafter, the operation of the electric motor 1 according to the present invention will be described. First, when the rotary shaft 3 is rotating at a high rotational speed, the liquid mixture is formed in the first flow path 2 or the second flow path 6. Is separated into a cooling liquid and a lubricating oil by centrifugal force. At this time, since the cooling liquid has a higher density than the lubricating oil as described above, it is distributed as a cooling liquid layer on the outer peripheral side of the rotating shaft 3 or the rotor 4 by centrifugal force, and on the contrary, mainly the lubricating oil is largely concentrated. The contained liquid (hereinafter simply referred to as “lubricating oil”) is distributed as a lubricating oil layer on the inner peripheral side of the rotating shaft 3 or the rotor 4.

  Therefore, when the mixed liquid flows from the left to the right in the figure, the cooling liquid separated in the first flow path 2 or the second flow path 6 is sent to the outer peripheral side of the rotor 4. Therefore, since the cooling liquid is supplied to the outer peripheral side of the rotor 4 or in the vicinity of the stator 5, the cooling performance can be improved as compared with the case where the lubricating oil or the mixed liquid is supplied. FIG. 3 is a graph showing the heat conduction performance of each liquid. Further, since a cooling liquid having a low viscosity is interposed in the gap (gap portion 8) between the rotor 4 and the stator 5 shown in FIG. 1, the friction of the liquid is smaller than when lubricating oil or a mixed liquid is supplied. The drag loss due to can be reduced.

  Next, a second configuration example of the electric motor 1 according to the present invention will be described. FIG. 4 shows the configuration. This configuration example is an improvement of the above-described first configuration example. The difference from the first configuration example is a configuration in which the outer peripheral side of the second flow path 6 is sealed. Furthermore, a through-hole 9 that penetrates from the second flow path 6 to the side surface of the end plate 4b is provided at a substantially central portion in the radial direction of the end plate 4b. The operation of the second configuration example is as follows. As the rotor 4 rotates, the cooling liquid and the lubricating oil supplied into the rotor 4 pass between the second steel plate 6 and the electromagnetic steel plates that are the core portion 4a. To do. At that time, as described above, the cooling liquid is distributed on the outer peripheral side by centrifugal force, so that it passes between the electromagnetic steel sheets and oozes out or flows between the stator 5 and the rotor 4. Therefore, a cooling liquid having a low viscosity is accumulated between the rotor 4 and the stator 5, and the stator 5 and the outer peripheral side of the rotor 4 can be cooled, and drag loss due to friction of the liquid can be reduced. . Then, the cooling liquid is discharged from between the stator 5 and the rotor 4 to the outside of the electric motor 1. FIG. 5 shows the difference in drag loss between the cooling liquid and the lubricating oil.

  Further, the lubricating oil supplied into the rotor 4 is distributed on the inner peripheral side from the cooling liquid by centrifugal force. Since the hydraulic pressure inside the end plate 4b becomes higher than the hydraulic pressure outside the end plate 4b due to the centrifugal hydraulic pressure, the lubricating oil is discharged to the outside of the electric motor 1 through the through hole 9 formed in the end plate 4b. Therefore, the electric motor 1 has a function as a separation device for separating the mixed liquid, and can flow the separated cooling liquid or lubricating oil smoothly or smoothly.

  Furthermore, the 3rd structure of the electric motor 1 which concerns on this invention is demonstrated. 6 and 7 are diagrams showing the configuration. As in the second configuration example, the third configuration example is configured to separate the cooling liquid and the lubricating oil from the mixed liquid and discharge each liquid from each discharge hole. Therefore, the rotating shaft 3, the core part 4a, the permanent magnet 4c, and the stator 5 are the same as in the first configuration example. The end plate 4b is formed up to the central portion in the radial direction of the core portion 4a, and the stationary plate 10 is provided on the side opposite to the core portion 4a and the side surface of the stator 5 with the end plate 4b in the figure interposed therebetween. Moreover, the 1st discharge hole 11 and the 2nd discharge hole 12 which each penetrated the end plate 4b are provided in the outer peripheral side and the inner peripheral side of the stationary plate 10, respectively. The stationary plate 10 is for causing a pressure difference between the inside of the end plate 4b or the rotor 4 and the outside of the stationary plate 10 to discharge the mixed liquid or lubricating oil to the outside of the stationary plate 10. Does not rotate integrally with the rotor. In other words, the stationary plate 10 is fitted to the rotating shaft 3 by “clearance fitting”, for example, and is provided in contact with or fixed to the stator 5 or a cover (not shown). Each of the discharge holes 11 and 12 may be provided one by one, but a plurality may be provided at intervals in the circumferential direction of the stationary plate 9 as shown in FIG.

  Therefore, the cooling liquid separated by the centrifugal force and distributed on the outer peripheral side of the rotor 4, that is, the cooling liquid that has flowed between the rotor 4 and the stator 5 through between the magnetic steel sheets forming the core portion 4 a. Alternatively, the cooling liquid that has flowed into the second flow path 6 flows out through the first discharge hole 11 to the outside of the electric motor 1 having a low hydraulic pressure. Further, the lubricating oil distributed on the inner peripheral side of the rotor 4 passes between the end plate 4b and the stationary plate 10 from the second discharge hole 12 through the outer peripheral end of the end plate 4b in the axial direction. It is discharged outside the electric motor 1 with low hydraulic pressure. Therefore, similarly to the second configuration example, it has a function as a separation device that separates the mixed liquid, and the separated cooling liquid and lubricating oil can flow smoothly or smoothly.

  Here, another shape of the first flow path 2 (hereinafter referred to as the third flow path 13) that can be used in each of the above-described configuration examples will be described. 8 and 9 show the third flow path 13, and the width of the third flow path 13 is formed so as to gradually narrow from the upstream side of the mixed liquid, that is, from the left side in the drawing. In other words, the inner periphery of the third flow path 13 located on the outer peripheral side of the rotating shaft 3 is inclined in the axial direction of the rotating shaft 3 from the upstream side to the downstream side of the third flow path 13. doing. Further, the third flow path 13 is formed at a position deviated in the radial direction from the rotation center of the rotation shaft 3. Accordingly, since the third flow path 13 is away from the center of the rotary shaft 3, a centrifugal force acts on the mixed liquid that passes through the third flow path 13, and the cooling liquid in the rotary shaft 3. And lubricating oil are easily separated. The cooling liquid that is separated and distributed on the outer peripheral side in the radial direction of the rotating shaft 3 is supplied to the rotor 4 from the supply hole 7 on the left side in the figure, and the mixed liquid having a relatively high concentration of lubricating oil is on the right side in the figure. Are supplied to the rotor 4 from the supply holes 7. Then, the lubricating oil distributed in the vicinity of the rotation center is further supplied to the gear train unit and the like connected to the electric motor 1 through the third flow path 13. Therefore, since the motor 1 and the gear train unit connected to the motor 1 can use the common rotating shaft 3, another device or a joint is provided between the motor 1 and the gear train unit. There is no need. Therefore, the structure of the entire apparatus can be reduced. Further, as compared with the conventional one, the mixed liquid can be separated only by changing the shape in the rotary shaft 3, so that it is not necessary to use another separation device or the like.

  In each of the configuration examples described above, in order to further improve the cooling performance on the outer peripheral side of the rotor 4, it is preferable to perform super oil repellency treatment only on the outer peripheral side of the side surface of the rotor 4. That is, fine irregularities are formed on the outer peripheral side surface of the rotor 4, and the low surface tension treatment agent is applied to the irregularities. Examples of the low surface tension treatment agent include a fluorine-based silane coupling agent and polydimethyl silicone. As described above, the super-oil-repellent treatment is performed only on the outer peripheral side of the side surface of the rotor 4, so that even when a small amount of lubricating oil is contained in the separated cooling liquid, the cooling liquid is easily adsorbed on the side surface of the rotor 4. Therefore, the cooling performance can be improved.

  Next, an example in which the electric motor 1 having the above-described third configuration example is mounted on the power transmission mechanism 14 of the vehicle will be described. First, the power transmission mechanism 14 will be briefly described. FIG. 10 is a skeleton diagram showing the power transmission mechanism 14. In the power transmission mechanism 14 mentioned here, an engine 15 that is an internal combustion engine is connected to a carrier 17 a of a first planetary gear mechanism 17 via a damper 16 and is connected to a sun gear 17 b of the first planetary gear mechanism 17. Is coupled to a motor MG1. The ring gear 17c of the first planetary gear mechanism 17 and the ring gear 18c of the second planetary gear mechanism 18 connected to the first planetary gear mechanism 17 are connected via a counter drive gear 19a. Yes. A motor MG <b> 2 is coupled to the sun gear 18 b of the second planetary gear mechanism 18. And the differential mechanism 20 is connected via the gear train part 19 containing the counter drive gear 19a. Each of the planetary gear mechanisms 17 and 18 and the gear train unit 19 or the differential mechanism 20 are hermetically sealed in one case (not shown), and the ring gear 20a of the differential mechanism 20 is located below the case. Provided in the department.

  Each member of the power transmission mechanism 15 described above is supplied from the oil pan 21 via the oil pump 22. Also, the oil reservoir 23 in the vicinity of the ring gear 20a of the differential mechanism 20 is scraped up to the ring gear 20a, and once accumulated in an oil receiving portion (not shown), the oil is supplied. The electric motor 1 according to the present invention can be mounted on the motor MG2 described above, and the mixed liquid is supplied from the oil pan 21 into the rotating shaft 3 of the motor MG2. Then, the mixed liquid is separated into the cooling liquid and the lubricating oil by the motor MG2. The cooling liquid flows to the heat generating portion of the motor MG2, that is, the stator 6 and the outer peripheral side of the rotor 5, cools those members, and then is sent to the oil reservoir 23 through the first discharge hole 11. . Further, the lubricating oil separated in the motor MG2 and the rotating shaft 3 passes through the second discharge hole 12 and the rotating shaft 3 provided in the motor MG2, and each planetary gear mechanism 17 connected to the motor MG2 18 and the gear train 19 are supplied to the oil reservoir 23. The cooling liquid and lubricating oil supplied to the oil sump 23 are stirred by the ring gear 20a of the differential mechanism 20 and returned to the original mixed liquid, and then supplied to the oil pan 21. The flow of the mixed liquid is shown in FIG.

With this configuration, the stator 6 and the outer peripheral side of the rotor 5 can be cooled by the cooling liquid separated by the rotating body, and drag loss due to the friction of the liquid generated in the rotor 5 and the stator 6 can be achieved. Can be reduced. Further, since the separated lubricating oil is supplied to the meshing portion and the bearing portion of the gear that require lubrication, seizure or the like can be prevented or suppressed. Furthermore, since the cooling liquid having a low viscosity is supplied to the vicinity of the ring gear 20a of the differential mechanism 20, the apparent viscosity in the vicinity of the ring gear 20a is reduced, and the agitation loss and drag loss due to the ring gear 20a being scraped are reduced. can do. In addition, the viscosity of a liquid mixture can be calculated | required by following Formula.
lnη = x ₁ lnη ₁ + x ₂ lnη ₂
In this equation, η is the viscosity of the mixed liquid, η ₁ is the viscosity of the cooling liquid, η ₂ is the viscosity of the lubricating oil, x ₁ is the ratio of the cooling liquid contained in the mixed liquid, and x ₂ is included in the mixed liquid. Indicates the ratio of lubricating oil.

  In addition, when only the lubricating oil is used, a large amount of lubricating oil is supplied to the heat generating part because the cooling performance is low. In the above configuration example, the mixed liquid is separated and the cooling liquid is supplied to the heat generating part. Since the cooling performance can be improved, the amount of mixed liquid, that is, the amount of oil can be reduced as compared with the case where only the lubricating oil is used.

  The present invention is not limited to the configuration example described above. In the configuration example described above, the cooling liquid having a density lower than that of the lubricating oil has been described as an example. However, a cooling liquid having a density higher than that of the lubricating oil may be used. That is, the high-density lubricating oil may be separated on the upstream side of the first or third flow path 2, 12, discharged from the flow path 2, 12, and then supplied with a cooling liquid. That is, the gear train portion 19 that supplies the lubricating oil may be disposed on the upstream side of the flow paths 2 and 12, and the electric motor 1 may be disposed on the downstream side.

  DESCRIPTION OF SYMBOLS 1 ... Electric motor 2, 6, 13 ... Channel, 3 ... Rotating shaft, 4 ... Rotor, 4a ... Core part, 4b ... End plate, 4c ... Permanent magnet, 5 ... Stator, 7 ... Supply hole, 8 ... Gap part , 9 ... Through hole, 10 ... Stationary plate, 11, 12 ... Discharge hole, 14 ... Power transmission mechanism, 15 ... Engine, 16 ... Damper, 17, 18 ... Planetary gear mechanism, 19 ... Gear train section, 20 ... Differential mechanism 21 ... Oil pan, 22 ... Oil pump, 23 ... Oil sump, MG1, MG2 ... Motor.

Claims (5)

In the electric motor in which the rotor is rotatably arranged on the inner peripheral side of the stator,
To the rotor or the rotating body that rotates integrally with the rotor,
A flow path is formed through which a mixed liquid in which a lubricating liquid and a cooling liquid having a lower viscosity than the lubricating oil and a density different from the lubricating oil are mixed is circulated,
Among the mixed liquids separated by centrifugal force by the rotor or the rotating body in the process of flowing through the flow path, a cooling flow path is provided for sending the cooling liquid to the stator via the rotor. An electric motor characterized by that. The rotor includes an end plate provided sandwiching laminated steel plates constituting the rotor in the axial direction,
The cooling channel is formed on the laminated steel plate side of the end plate,
The electric motor according to claim 1, further comprising a through-hole communicating with the cooling channel and the opposite side across the end plate. The rotor includes an end plate provided sandwiching laminated steel plates constituting the rotor in the axial direction,
There is further provided a stationary plate provided with a gap on both side surfaces in the axial direction of the end plate and provided in contact with both side surfaces in the axial direction of the stator,
The electric motor according to claim 1, wherein a discharge hole penetrating the stationary plate is formed on each of an outer peripheral side and an inner peripheral side of the stationary plate. The rotating body includes a rotating shaft provided on an outer periphery of the rotor,
The flow path is formed with the rotation shaft hollow.
The inner circumference of the flow path located on the outer peripheral side of the rotary shaft is inclined in the axial direction of the rotary shaft from the upstream side to the downstream side of the flow path. 4. The electric motor according to any one of 3. The mixed liquid includes a cooling liquid having a lower density than the lubricating oil,
5. The super-oil-repellent treatment having a strong affinity with the cooling liquid and a strong affinity with the cooling liquid is performed on the outer peripheral side surface of the rotor. The electric motor described in 1.

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