JP5434217B2 - Rotating electric machine - Google Patents

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotating electrical machine having a cooling medium enclosed in a motor case.

  2. Description of the Related Art Conventionally, a motor including a rotor having a permanent magnet mounted on a rotor core, a stator having stator windings wound around the stator core, a motor case incorporating the rotor and the stator, and a motor A rotating electrical machine is known in which refrigerant oil is enclosed in a case, the refrigerant oil is scraped up in a motor case using centrifugal force generated by the rotation of a rotor, and a necessary part is cooled (for example, Patent Document 1). reference).

JP 2001-37129 A

  By the way, in the conventional rotating electrical machine, when the output rotational speed of the rotor increases and reaches a predetermined rotational speed, a centrifugal force by the rotor increases, and a phenomenon occurs in which refrigerant oil accumulates on the upper side in the gravity direction of the motor case. . When a certain amount of refrigerant oil accumulates, the refrigerant oil falls without being able to withstand its own weight, and as a result, the amount of refrigerant oil on the lower side of the motor case in the gravitational direction increases rapidly.

  However, when the amount of refrigerant oil increases rapidly, the shear resistance of the refrigerant oil filled in the gap between the rotor and the stator increases, resulting in a problem that motor torque loss due to oil drag increases.

  The present invention has been made paying attention to the above-mentioned problem, and even if the rotational speed of the rotor is high, the uneven distribution of the cooling medium in the motor case is alleviated and the increase in motor torque loss is prevented. An object of the present invention is to provide a rotating electrical machine that can perform the above.

  To achieve the above object, in the present invention, in a rotating electrical machine including a rotor and a stator, a motor case incorporating the rotor and the stator, and a cooling medium sealed in the motor case, the motor case is The upper internal space located on the upper side in the gravitational direction communicates with the lower internal space located on the lower side in the gravitational direction and has a refrigerant adjustment path through which the cooling medium can flow.

  Therefore, in the rotating electrical machine of the present invention, even if the rotation speed of the stator is high and the cooling medium accumulates on the upper inner space side of the motor case, the cooling accumulated in the upper inner space via the refrigerant adjustment path. The medium can be flowed to the lower inner space side of the motor case. As a result, the uneven distribution of the cooling medium in the motor case is alleviated, and it is possible to prevent the motor torque loss due to oil drag from increasing due to the rapid increase in the cooling medium.

  As a result, even when the rotational speed of the rotor is high, it is possible to alleviate the uneven distribution of the cooling medium in the motor case and prevent an increase in motor torque loss.

It is a schematic sectional drawing which shows the structure of the rotary electric machine of Example 1. FIG. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. FIG. 6 is a schematic cross-sectional view illustrating a configuration of a first modification of the rotating electrical machine according to the first embodiment. It is CC sectional drawing in FIG. FIG. 6 is a schematic cross-sectional view illustrating a configuration of a second modification of the rotating electrical machine according to the first embodiment. It is DD sectional drawing in FIG. It is explanatory drawing which shows the principal part of the 2nd modification in the rotary electric machine of Example 1. FIG.

  Hereinafter, the form for implementing the rotary electric machine of this invention is demonstrated based on Example 1 shown on drawing.

First, the configuration will be described.
FIG. 1 is a schematic cross-sectional view illustrating the configuration of the rotating electrical machine according to the first embodiment. 2 is a cross-sectional view taken along line AA in FIG. 3 is a cross-sectional view taken along the line BB in FIG. In addition, the direction shown by the arrow X in each figure is a gravity direction lower side.

  The rotating electrical machine 1A according to the first embodiment is an AC synchronous motor used as a drive motor of, for example, a hybrid vehicle or an electric vehicle, and includes a rotor (rotor) 10, a stator (stator) 20, the rotor 10, and a fixed motor. A motor case 30 containing the child 20 and a refrigerant oil (cooling medium) OIL sealed in the motor case 30 are provided.

  The rotor 10 includes a rotating shaft (shaft) 11 and a rotor core 13 attached to the rotating shaft 11 via a rotor holding member 12. The rotating shaft 11 penetrates the motor case 30 and is rotatably held by first and second end plate portions 32A and 32B (to be described later) of the motor case 30 via ball bearings B1 and B2. The rotor holding member 12 is fixed to an intermediate portion of the rotating shaft 11 by a plurality of screws N. The rotor core 13 includes a rotor core 13a formed by laminating a large number of ring-shaped magnetic thin plates, and a plurality of permanent magnets 13b composed of rare earth magnets embedded and fixed near the outer peripheral surface of the rotor core 13a, have. In addition, the permanent magnet 13b is arrange | positioned so that a polarity may change alternately along the circumferential direction of the rotor part iron core 13a. The rotor core 13a has end rings 13c attached to both ends in the axial direction, respectively, and one end ring 13c and the rotor holding member 12 are integrally fixed by a fixing portion 14. Thereby, the rotating shaft 11, the rotor holding member 12, and the rotor core 13 are integrally rotatable.

  The stator 20 includes a plurality of split cores 21 (see FIG. 2) and stator windings (coils) 22 that are wound around the split cores 21 via insulators (not shown). . As shown in FIG. 2, the plurality of split cores 21 are connected in an annular shape that surrounds the outer periphery of the rotor 10, and constitute a stator core 21 a. Further, the stator winding 22 is an enameled wire having a rectangular cross section, and is wound around a tooth portion 23 of each divided core 21. The stator core 21 a is fixed inside the motor case 30.

  The motor case 30 covers the cylindrical housing portion 31 that covers the outer peripheral surfaces of the rotor 10 and the stator 20, and both axial end surfaces of the rotor 10 and the stator 20, and is attached to both ends of the housing portion 31. First and second end plate portions 32A and 32B.

  The housing portion 31 has a cylindrical shape with both ends open, a large number of heat radiation fins 31a are formed on the outer peripheral surface, and the stator core 21a of the stator 20 is fixed to the inner peripheral surface. The first and second end plate portions 32A and 32B are fixed so as to close both open ends of the housing portion 31, and shaft through holes 33 through which the rotary shaft 11 passes are formed at the respective centers. ing.

  A cylindrical first shaft holding member 34 surrounding the shaft through hole 33 is fixed inside the first end plate portion 32A (inside the housing portion 31) by a plurality of screws N1, and this first shaft holding member. A ball bearing B <b> 1 is disposed between 34 and the rotating shaft 11. Reference numeral 35a denotes a lip seal portion for maintaining the airtightness in the motor case 30, and reference numeral 35b denotes a C ring that defines the axial position of the ball bearing B1.

  A cylindrical second shaft holding member 36 is fitted inside the shaft through hole 33 of the second end plate portion 32B, and the ball bearing B2 is interposed between the second shaft holding member 36 and the rotating shaft 11. Is arranged. In addition, 36a is a lip seal part for maintaining airtightness in the motor case 30, and 36b is a C-ring that defines the axial position of the ball bearing B2. Further, the second end plate portion 32B has a pair of first and second discs 32Ba and 32Bb that are overlapped in the axial direction.

  The first disc 32Ba is disposed on the housing portion 31 side, and as shown in FIG. 3, the first and second through holes 37a and 37b located on the same diameter with the shaft through hole 33 interposed therebetween, The first and second through holes 37a and 37b are connected to each other and a first communication groove 38 formed on one end surface, and the first through hole 37a extends from the first through hole 37a to the shaft through hole 33 and is formed on one end surface. Two communication grooves 39 are formed.

  The first communication groove 38 has a U-shape in front view so as not to be buffered with the shaft through hole 33 (see FIG. 3). Further, the second communication groove 39 communicates with the refrigerant passage 36 c that penetrates the second shaft holding member 36 in the radial direction. Therefore, the first through hole 37a communicates with the space H generated by the ball bearing B2 between the rotating shaft 11 and the second shaft holding member 36 via the second communication groove 39 and the refrigerant passage 36c. Here, this space H faces the ball bearing B2. Further, the first and second communication grooves 38, 39 and the refrigerant passage 36c have a width (inner diameter) and a depth through which the refrigerant oil OIL can flow.

  On the other hand, the second disc 32Bb is fixed without gap to one end surface of the first disc 32Ba where the first and second communication grooves 38 and 39 are formed, and the first and second through holes 37a. 37b, the first communication groove 38, and the second communication groove 39 are covered.

  The second end plate portion 32B formed by overlapping the first and second disks 32Ba and 32Bb is opposed to the upper inner space 30a in which the first through hole 37a is located above the motor case 30 in the gravity direction. The second through hole 37b is attached to the housing portion 31 in a state of facing the lower inner space 30b located on the lower side of the motor case 30 in the gravity direction.

  At this time, the first and second through holes 37a and 37b are located on the radially outer side of the outer peripheral surface of the rotor 10, respectively. That is, the first and second through holes 37 a and 37 b are opened at positions radially outside the outer peripheral surface of the rotor core 13. Further, here, the first through hole 37a is located on the radially outer side than the second through hole 37b. That is, the distance from the shaft through hole 33 to the first through hole 37a is longer than the distance from the shaft through hole 33 to the second through hole 37b.

  Thus, the first through hole 37a corresponds to a refrigerant inlet opening to the upper inner space 30a of the motor case 30, and the second through hole 37b is a refrigerant outlet opening to the lower inner space 30b of the motor case 30. Correspondingly, the first communication groove 38 covered with the second disk 32Bb communicates with the upper inner space 30a and the lower inner space 30b, and corresponds to a refrigerant adjustment path through which the refrigerant oil OIL can flow. Further, the second communication groove 39 covered with the second disk 32Bb corresponds to a lubricating oil flow path that connects the upper inner space 30a and the space H.

  The refrigerant oil OIL is a cooling medium that transmits heat of the stator winding 22 of the stator 20 to the motor case 30. As shown in FIG. 1, the refrigerant oil OIL has a part of the lower side of the rotor 10 when the rotor 10 is in a stopped state and the entire amount of the refrigerant oil OIL is stored in the lower inner space 30 b under its own weight. An amount of immersion is enclosed in the motor case 30.

Next, the operation will be described.
In the rotating electrical machine 1A of the first embodiment, when the stator winding 22 is excited by an inverter (not shown), a rotating magnetic field is formed in the circumferential direction of the stator 20, and the permanent magnets are arranged so that the polarities are alternately different in the circumferential direction. The rotor core 13 in which 13b is embedded is attracted and repelled by the rotating magnetic field generated by the stator 20, and the rotor core 13 rotates together with the rotating shaft 11 in synchronization with the rotating magnetic field.

  At this time, the refrigerant oil OIL enclosed in the motor case 30 is scraped up from the lower side in the gravitational direction of the motor case 30 toward the upper side in the gravitational direction by the rotation of the rotor 10. Then, as the rotational speed of the rotor 10 increases, the centrifugal force (scraping force) generated by this rotation, the viscosity of the refrigerant oil OIL itself, and the like spread while sticking to almost the entire inner surface of the motor case 30. Circulates in the motor case 30. Thereby, the heat generated from the stator 20 is transmitted to the motor case 30 via the refrigerant oil OIL, and further radiated through the heat radiation fins 31a. At this time, the refrigerant oil OIL flows radially outward due to the centrifugal force of the rotor 10, and at the same time, is dragged by the rotor 10 and flows in the rotation direction of the rotor 10. Therefore, dynamic pressure along the rotational direction of the rotor 10 and dynamic pressure toward the radially outer side act on the inner surface of the motor case 30.

  And when the rotation speed of the rotor 10 rises and becomes a high rotation area (for example, 1000 rpm or more), the centrifugal force generated by the rotor 10 becomes strong, and the amount of the refrigerant oil OIL accumulated in the upper inner space 30a of the motor case 30 is reduced. To increase.

  Here, a first through hole 37a formed in the second end plate portion 32B is opened in the upper inner space 30a. The first through hole 37a is opened to the inside of the motor case 30 of the second end plate portion 32B, so that the first through hole 37a is opened in a direction to receive dynamic pressure with respect to the flow direction of the refrigerant oil OIL circulating in the motor case 30. It becomes.

  As a result, the refrigerant oil OIL accumulated in the upper inner space 30a enters the first through hole 37a due to dynamic pressure, flows down the first communication groove 38 by its own weight, and opens from the second through hole 37b opened to the lower inner space 30b. Discharged.

  In particular, here, the distance from the shaft through hole 33 to the first through hole 37a is longer than the distance from the shaft through hole 33 to the second through hole 37b, and therefore acts on the first through hole 37a. The dynamic pressure that is applied is greater than the dynamic pressure that acts on the second through hole 37b. The refrigerant oil OIL that has entered from the first through hole 37a due to this pressure difference is smoothly discharged from the second through hole 37b.

  Each of the first and second through holes 37a and 37b is adjusted by adjusting the distance from the shaft through hole 33 to the first through hole 37a and the distance from the shaft through hole 33 to the second through hole 37b. The pressure difference acting on the refrigerant oil OIL can be controlled, and the discharge amount and discharge direction of the refrigerant oil OIL can be arbitrarily adjusted. Further, by adjusting the distance from the inner peripheral surface of the housing portion 31 to the first through hole 37a, the amount of refrigerant oil accumulated in the upper inner space 30a of the motor case 30 can be adjusted.

  Then, the refrigerant oil OIL discharged from the second through hole 37 b flows into the lower inner space 30 b of the motor case 30. Thus, the refrigerant oil OIL accumulated in the upper inner space 30a can be smoothly guided to the lower inner space 30b. Therefore, it is possible to alleviate the uneven distribution of the refrigerant oil OIL in the motor case 30.

  That is, the refrigerant oil OIL accumulated in the upper inner space 30a falls into the lower inner space 30b all at once, and the amount of refrigerant oil in the lower inner space 30b increases abruptly to form a gap between the rotor 10 and the stator 20. The shear resistance of the filled refrigerant oil OIL increases, and motor torque loss due to oil drag does not increase.

  As a result, even when the rotation speed of the rotor 10 is high (when rotating in a high rotation region), the uneven distribution of the refrigerant oil distribution in the motor case 30 is alleviated and an increase in motor torque loss is prevented. be able to.

  Further, the rotating electrical machine 1A according to the first embodiment has the second communication groove 39 extending from the first through hole 37a to the space H, so that the refrigerant oil OIL that has entered the first through hole 37a is in the second communication hole. It can also flow into the space H through the groove 39. Here, since the space H faces the ball bearing B2, the refrigerant oil OIL is supplied to the ball bearing B2 and becomes lubricating oil. That is, the first communication groove 38 that connects the first through hole 37a and the second through hole 37b is formed in the second end plate portion 32B, so that the first through hole 37a is disposed inside the shaft through hole 33 of the second end plate portion 32B. The refrigerant oil OIL can be supplied to the ball bearing B2 and the like as the lubricating oil by utilizing the rotation of the rotor 10, and a part of the refrigerant oil OIL can be used as the lubricating oil for the ball bearing B2. For this reason, simplification of the lubricating structure of the ball bearing B2 can be achieved.

  Furthermore, in the rotating electrical machine 1A according to the first embodiment, the first through hole 37a into which the refrigerant oil OIL enters is located radially outside the outer peripheral surface of the rotor 10, so that the centrifugal force generated by the rotation of the rotor 10 is achieved. Thus, the refrigerant oil OIL circulating so as to stick to the inner surface of the motor case 30 can be efficiently taken into the first through hole 37a.

  In the rotating electrical machine 1A according to the first embodiment, the first through hole 37a is opened in a direction to receive the dynamic pressure with respect to the flow direction of the refrigerant oil OIL circulating in the motor case 30. The refrigerant oil OIL can be taken into the first through hole 37a more efficiently using the pressure.

Next, the effect will be described.
In the rotary electric machine 1A according to the first embodiment, the effects listed below can be obtained.

  (1) A rotating electrical machine including a rotor 10 and a stator 20, a motor case 30 incorporating the rotor 10 and the stator 20, and a cooling medium (refrigerant oil OIL) enclosed in the motor case 30. In 1A, the motor case 30 has a refrigerant inflow opening (to the first through hole 37a) that opens to the upper inner space 30a located on the upper side in the gravity direction, and a refrigerant flow that opens to the lower inner space 30b located on the lower side in the gravity direction. An outlet (second through-hole 37b), communicates the upper inner space 30a and the lower inner space 30b, and has a refrigerant adjustment path (first communication groove 38) through which the cooling medium OIL can flow. The configuration. For this reason, even if the rotation speed of the rotor 10 is high, the uneven distribution of the cooling medium in the motor case 30 can be alleviated, and an increase in motor torque loss can be prevented.

  (2) The refrigerant inlet 37 a is configured to be located radially outside the outer peripheral surface of the rotor 10. Therefore, the cooling medium OIL that circulates while sticking to the inner surface of the motor case 30 by the centrifugal force generated by the rotation of the rotor 10 can be efficiently taken into the refrigerant adjustment path 38.

  (3) The refrigerant inlet 37a is configured to open in a direction to receive dynamic pressure with respect to the flow direction of the cooling medium OIL that flows due to the centrifugal force generated by the rotation of the rotor 10. For this reason, when the cooling medium OIL is taken into the refrigerant adjustment path 38, the dynamic pressure due to the flow rate of the cooling medium OIL can be used, and the cooling medium OIL can be taken in more efficiently.

  (4) The motor case 30 includes a pair of cylindrical housing portions 31 that cover the outer peripheral surfaces of the rotor 10 and the stator 20 and a pair of axial ends of the rotor 10 and the stator 20. End plate portions (first end plate portion 32A, second end plate portion 32B), and the refrigerant adjustment path 38 is formed on at least one of the pair of end plate portions 32A, 32B. . Therefore, a part of the cooling medium OIL can be supplied as lubricating oil to the ball bearing B2 and the like that support the rotor 10 attached to the second end plate portion 32B, and the lubrication mechanism can be simplified.

  FIG. 4 is a schematic cross-sectional view illustrating a configuration of a first modification of the rotating electrical machine according to the first embodiment. 5 is a cross-sectional view taken along the line CC in FIG. In addition, the direction shown by the arrow X in each figure is a gravity direction lower side.

  In the rotating electrical machine 1A of the first embodiment, the first and second through holes 37a and 37b and the first communication groove 38 are formed in the second end plate portion 32B of the motor case 30, but the present invention is not limited thereto. As in the rotating electrical machine 1 </ b> B illustrated in FIG. 4, the first and second through holes 37 a and 37 b and the first communication groove 38 may be formed in the housing portion 31 of the motor case 30.

  That is, the first and second through holes 37a and 37b are opened to the inner peripheral surface of the cylindrical housing part 31, respectively, and the first communication groove 38 penetrates the housing part 31 in the circumferential direction. In order to form the first communication groove 38, first, the housing portion 31 is divided in the axial direction at the position where the first communication groove 38 is formed, and after the first communication groove 38 is formed on the divided end surface, both are formed. Conclude.

  At this time, the first through hole 37a corresponding to the refrigerant inlet is opened in a direction to receive dynamic pressure with respect to the flow direction of the refrigerant oil OIL generated by the rotation of the rotor 10. That is, in FIG. 5, the rotor (not shown here) rotates clockwise around the rotation shaft 11, so that the refrigerant oil OIL also flows clockwise as indicated by the arrow. Therefore, the refrigerant oil OIL can be efficiently taken from the first through hole 37a formed on the right side surface in FIG.

  Further, since the first communication groove 38 extends along the circumferential direction of the motor case 30, when the refrigerant oil OIL flows from the first through hole 37 a to the first communication groove 38 and the second through hole 37 b, The flow direction does not bend in the axial direction. Therefore, the resistance in the first communication groove 38 is reduced, and the refrigerant oil OIL can be taken in more efficiently.

  Then, the refrigerant oil OIL taken in from the first through hole 37 a and flowing through the first communication groove 38 is discharged from the second through hole 37 b and flows into the lower inner space 30 b of the motor case 30. For this reason, the uneven distribution of the refrigerant oil distribution in the motor case 30 can be mitigated, and an increase in motor torque loss can be prevented.

  That is, in the first modification of the first embodiment described above, the following effect (5) can be obtained in addition to the effects (1) to (3) described above.

  (5) The motor case 30 includes a pair of cylindrical housing portions 31 that cover the outer peripheral surfaces of the rotor 10 and the stator 20 and a pair of axial ends of the rotor 10 and the stator 20. End plate portions 32 </ b> A and 32 </ b> B are provided, and the refrigerant adjustment path (first communication groove 38) is formed in the housing portion 31. For this reason, the refrigerant | coolant adjustment path 38 can be formed along the flow direction of a cooling medium (refrigerant oil OIL), and flow path resistance can be reduced and it can flow smoothly.

  FIG. 6 is a schematic cross-sectional view illustrating a configuration of a second modification of the rotating electrical machine according to the first embodiment. 7 is a cross-sectional view taken along the line DD in FIG. In addition, the direction shown by the arrow X in each figure is a gravity direction lower side.

  In the rotating electrical machine 1A according to the first embodiment, an example in which the first and second through holes 37a and 37b and the first communication groove 38 are formed in the second end plate portion 32B of the motor case 30 is shown. Although the example which forms the 2nd through-holes 37a and 37b and the 1st communicating groove 38 in the housing part 31 of the motor case 30 was shown, it does not restrict to this. As in the rotating electric machine 1C shown in FIG. 6, the first and second through holes 37a and 37b and the first communication groove 38 are in contact with the outer peripheral surface of the stator core 21a of the stator 20, that is, the stator core 21a and You may form between the housing parts 31 of the motor case 30. FIG.

  In FIG. 6, the stator core 21 a of the stator 20 is held at its axial ends by a pair of holding projections 40, 40 formed on the inner peripheral surface of the housing portion 31.

  And the 1st through-hole 37a corresponded to a refrigerant | coolant inflow port penetrates one holding protrusion 40, and is formed by notching a part of stator core 21a. Further, the first communication groove 38 corresponding to the refrigerant adjustment path is formed to extend in the circumferential direction at a position on the inner peripheral surface of the housing portion 31 and facing the outer peripheral surface of the stator core 21a. Thus, the first communication groove 38 is formed at a position in contact with the outer peripheral surface of the stator core 21a of the stator 20. Further, the second through hole 37b corresponding to the refrigerant outlet is formed by cutting through a part of the stator core 21a while penetrating one holding projection 40.

  Here, as shown in FIG. 7, the 1st through-hole 37a formed in the stator core 21a is formed in the circumferential direction center part of the back yoke part 24 of the division | segmentation core 21 located in the gravity direction uppermost part. . Further, the second through hole 37b is formed at the center in the circumferential direction of the back yoke portion 24 of each of the two split cores 21 located at the lowest part in the gravity direction.

  Normally, as shown in FIG. 8, the magnetic flux input from the tip of the tooth portion 23 flows from both circumferential ends of the back yoke portion 24. That is, the magnetic flux density is lowest at the circumferential center portion of the back yoke portion 24. Then, by forming the first and second through holes 37a and 37b in the center portion in the circumferential direction of the back yoke portion 24, the first and second through holes 37a and 37b are formed at positions that do not hinder the flow of magnetic flux. The Rukoto.

  Thereby, it can prevent that the 1st, 2nd through-holes 37a and 37b deteriorate the magnetic performance of 1 C of rotary electric machines.

  The refrigerant oil OIL that has flowed from the first through hole 37a into the first communication groove 38 flows downward under its own weight along the outer peripheral surface of the stator core 21a, and the motor case 30 passes through the second through hole 37b. It can flow out to the lower inner space 30b.

  At this time, when the refrigerant oil OIL moves toward the lower inner space 30b, the refrigerant oil OIL flows along the outer peripheral surface of the stator core 21a, so that the heat of the stator core 21a can be taken. Therefore, the stator core 21a can be cooled from the outside, and the cooling efficiency of the stator 20 can be increased to improve the thermal limit output of the rotating electrical machine 1C.

  That is, in the second modification of the first embodiment described above, the following effects (6) and (7) can be obtained in addition to the effects (1) to (3) described above.

  (6) The refrigerant adjustment path (first communication groove 38) is formed at a position in contact with the outer peripheral surface of the stator 20. Therefore, when the cooling medium (refrigerant oil OIL) flows from the refrigerant inlet (first through hole 37a) to the refrigerant outlet (second through hole 37b) via the refrigerant adjustment path 38, the stator 20 is fixed. The child core 21a can be cooled, and the thermal limit output can be improved.

  (7) The refrigerant inlet 37a and the refrigerant outlet 37b are formed at positions that do not hinder the flow of magnetic flux. For this reason, the stator core 21a can be cooled when the cooling medium OIL is returned to the lower inner space without deteriorating the magnetic performance.

  As mentioned above, although the rotary electric machine of this invention has been demonstrated based on Example 1, it is not restricted to these Examples about concrete structure, The summary of the invention which concerns on each claim of a claim is shown. Unless it deviates, design changes and additions are allowed.

  It should be noted that the number and size (width, depth, length, etc.) of the refrigerant adjustment paths are design requirements and cannot be unambiguously defined because the optimum value varies depending on the shape and conditions. However, in consideration of cooling medium discharge efficiency, space saving, and the like, it is preferable that the opening areas of the refrigerant inlet and the refrigerant outlet are equal.

  In addition, the position where the refrigerant inlet and the refrigerant outlet are provided defines the radially outer position from the outer peripheral surface of the rotor 10 in Example 1, but the circumferential position is a design requirement, Since the optimum value varies depending on conditions and the like, it cannot be uniquely defined. Although it is preferable to provide it near the position where the flow velocity vector acting on the cooling medium and the gravity vector form a right angle, the exact optimal position is analyzed by analyzing the scattering state of the cooling medium in the motor case 30 by experiments or numerical calculations. It is desirable to set.

1A Rotating electrical machine 10 Rotor 20 Stator 30 Motor case 30a Upper inner space 30b Lower inner space 37a First through hole (refrigerant inlet)
37b Second through hole (refrigerant outlet)
38 First communication groove (refrigerant adjustment path)
OIL refrigerant oil (cooling medium)

Claims (7)

In a rotating electrical machine comprising a rotor and a stator, a motor case containing the rotor and the stator, and a cooling medium encapsulated in the motor case and swept up by the rotor,
When the rotor is in a stopped state, the rotor is partially immersed in the cooling medium stored in the lower inner space located on the lower side of the motor case in the direction of gravity, and rotates to cause the cooling medium to move downward in the direction of gravity of the motor case. From the side to the upper side in the direction of gravity,
The motor case has a coolant inlet which opens in the upper space located in the direction of gravity upward, and a refrigerant outlet which opens into the lower space communicates with said lower space and the upper space In addition, the rotating electrical machine has a refrigerant adjustment path through which the cooling medium can flow. In the rotating electrical machine according to claim 1,
The rotating electrical machine according to claim 1, wherein the refrigerant inflow port is located radially outside the outer peripheral surface of the rotor. In the rotating electrical machine according to claim 1 or 2,
The rotary electric machine is characterized in that the refrigerant inlet is opened in a direction to receive a dynamic pressure with respect to a flow direction of the cooling medium flowing by a centrifugal force generated by rotation of the rotor. In the rotating electrical machine according to any one of claims 1 to 3,
The motor case includes a cylindrical housing portion that covers outer peripheral surfaces of the rotor and the stator, and a pair of end plate portions that respectively cover both end surfaces in the axial direction of the rotor and the stator,
The rotating electrical machine, wherein the refrigerant adjustment path is formed in at least one of the pair of end plate portions. In the rotating electrical machine according to any one of claims 1 to 3,
The motor case includes a cylindrical housing portion that covers outer peripheral surfaces of the rotor and the stator, and a pair of end plate portions that respectively cover both end surfaces in the axial direction of the rotor and the stator,
The rotary electric machine characterized in that the refrigerant adjustment path is formed in the housing part. In the rotating electrical machine according to any one of claims 1 to 3,
The rotating electrical machine, wherein the refrigerant adjustment path is formed at a position in contact with an outer peripheral surface of the stator. In the rotating electrical machine according to claim 6,
The rotating electrical machine, wherein the refrigerant inlet and the refrigerant outlet are formed at positions that do not hinder the flow of magnetic flux.

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