JP2019154111A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine comprising a rotor and a coil, and allowing for appropriate cooling of the rotor and each coil end portion of the coil while suppressing an increase in output of a pump device for supplying coolant to the rotor and the coil end.SOLUTION: The rotary electric machine comprises a rotor 12, a stator 11, and a coolant main passage 24. The rotor 12 is provided with a plurality of permanent magnets 20 on an outer periphery and rotates integrally with a rotary shaft 13. The stator 11 is wound with a coil 17 and is disposed on a radially outer side of the rotor 12. The rotary electric machine further comprises a first passage 26, a second passage 27, and an opening and closing adjustment unit that opens and closes the second passage according to a driving state. The first passage 26 supplies a coolant supplied to a coolant main passage 24 to a first coil end 18 f via an inside of the rotor 12. The second passage 27 branches from the coolant main passage 24 and supplies the coolant to a second coil end 18s.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a rotating electrical machine that is cooled by a coolant.

A rotating electrical machine mounted on a vehicle or the like includes a rotor that rotates integrally with a rotating shaft, and a stator that is disposed radially outside the rotor. A plurality of permanent magnets are disposed on the outer periphery of the rotor, and the stator Some have coils wound around. In this type of rotating electrical machine, the permanent magnet of the rotor and the coil portion of the stator are likely to generate heat during operation.
As a countermeasure against this, a rotating electrical machine is known in which the coil ends of the rotor and the stator are cooled by a coolant (see, for example, Patent Document 1).

  In the rotating electrical machine described in Patent Document 1, a coolant supply section (coolant main passage) is connected to an axial passage in a rotor through a passage in a rotating shaft, and an oil hole is provided at an end of the axial passage. ing. The coolant supplied to the axial passage cools the inside of the rotor, and is scattered and supplied to the coil end portion of the stator coil by the centrifugal force accompanying the rotation of the rotor.

Japanese Patent Laid-Open No. 9-182374

  The rotating electrical machine described in Patent Document 1 can cool both the inside of the rotor and the coil end portion of the coil with the coolant while the rotor is rotating. However, the coil end portions on one end side and the other end side in the axial direction of the stator may differ in the degree of heat generation (ease of heat generation) depending on the specifications. If sufficient cooling is desired, the output of the pump device, which is the supply source of the coolant, must be increased, and the pump device must be increased in size and energy consumption.

  Accordingly, the present invention is intended to provide a rotating electrical machine capable of appropriately cooling the rotor and each coil end portion of the coil while suppressing an increase in output of the pump device for supplying the coolant.

The rotating electrical machine according to the present invention employs the following configuration in order to solve the above problems.
That is, in the rotating electrical machine according to the present invention, a plurality of permanent magnets (for example, the permanent magnet 20 of the embodiment) are arranged on the outer periphery, and the rotor (for example, the rotating shaft 13 of the embodiment) rotates together with the rotor ( For example, the rotor 12) according to the embodiment, a coil (for example, the coil 17 according to the embodiment) and a stator (for example, the stator 11 according to the embodiment) disposed outside in the radial direction of the rotor, and a cooling liquid A coolant main passage (for example, the coolant main passage 24 of the embodiment) to be supplied, and a first coil end (for example, the first coil end 18f of the embodiment) of the coil is one end in the axial direction of the rotor. In the rotating electrical machine in which the second coil end of the coil (for example, the second coil end 18s of the embodiment) is exposed and arranged on the other end side in the axial direction of the rotor. A first passage (for example, the first passage 26 in the embodiment) for supplying the coolant supplied to the coolant main passage to the first coil end via the rotor, and the coolant main passage. A second passage (for example, the second passage 27 of the embodiment) that branches and supplies the coolant to the second coil end, and an opening / closing adjustment unit (for example, the embodiment) that opens and closes the second passage according to an operating situation. And a valve device 28).

  With the above configuration, for example, when the rotational speed of the rotor is low, the opening / closing adjustment unit closes the second passage, and the coolant supplied to the coolant main passage passes through the first passage in the rotor. And supplied to the first coil end of the stator. Thereby, when the coolant passes through the first passage in the rotor, the rotor is cooled, and further, the coolant supplied to the first coil end cools the first coil end. For example, when the rotational speed of the rotor becomes high, the opening / closing adjustment unit opens the second passage, and a part of the coolant supplied to the coolant main passage passes through the second passage to the second coil end. Supplied directly. Thereby, the coolant introduced into the first passage cools the rotor and the first coil end, and the coolant introduced into the second passage cools the second coil end.

The second passage is preferably branched from the coolant main passage on the upstream side of the first passage.
In this case, since the second passage branches on the upstream side of the first passage that cools the inside of the rotor, the coolant that is not warmed by the heat of the rotor can be supplied to the second coil end of the coil. For this reason, the 2nd coil end of a coil can be cooled efficiently.

The opening / closing adjustment unit may be configured to adjust an opening / closing state of the second passage according to a supply pressure of the coolant.
In this case, since the second passage can be opened with the coolant supply pressure sufficiently increased, the coolant can be stably supplied from the second passage to the second coil end.

The coolant main passage may be connected to a pump device (for example, the pump device 23 of the embodiment) in which the discharge pressure of the coolant increases or decreases in conjunction with the rotation of the rotor.
In this case, when the rotational speed of the rotor increases, the discharge pressure of the pump device increases accordingly, and the pressure of the coolant in the coolant main passage also increases. For this reason, when this configuration is adopted, the supply of the coolant to the second passage can be increased according to the increase in the rotational speed of the rotor without using complicated control.

The opening / closing adjustment unit is a valve device (for example, an implementation) in which a valve body (for example, the valve body 34 of the embodiment) urged in the valve closing direction is opened according to the pressure of the coolant in the coolant main passage. It may be constituted by a valve device 28) of the form.
In this case, the opening / closing adjustment unit can be configured with a simple configuration that can be downsized. For this reason, when this configuration is adopted, it is possible to reduce the size of the rotating electrical machine and reduce the product cost.

On the other end side in the axial direction of the rotor, an end cover (for example, the end cover 22 of the embodiment) that covers the other end side in the axial direction of the rotor in a non-contact state is provided. The end face on the side facing the rotor has a plurality of passage grooves (for example, the passage groove 33 in the embodiment) extending radially outward in the radial direction, and the end portion on the side facing the rotor of the end cover A closing plate (for example, the closing plate 29 in the embodiment) may be coupled to the end passage, and the passage groove of the end cover and the closing plate may constitute a part of the second passage.
In this case, a part of the second passage can be easily formed simply by forming a passage groove in the end cover that covers the other end side of the rotor in the axial direction and coupling the closing plate to the end cover. . Therefore, when this configuration is adopted, it is possible to reduce the size of the rotating electrical machine and reduce the product cost by simplifying the structure.

  The present invention provides a second passage for branching from the coolant main passage and supplying the coolant to the second coil end separately from the first passage for supplying the coolant to the first coil end via the inside of the rotor. The second passage is configured to be opened and closed by the opening / closing adjustment unit according to the driving situation. For this reason, according to the present invention, it is possible to appropriately cool the rotor, the first coil end and the second coil end of the coil while suppressing an increase in the output of the pump device for supplying the coolant.

It is a longitudinal cross-sectional view of the rotary electric machine of one Embodiment of this invention. It is an end view of the end cover of the rotary electric machine of one Embodiment of this invention. It is a longitudinal cross-sectional view of the rotary electric machine of one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing a rotary electric machine 10 according to an embodiment in a longitudinal section along an axial direction.
The rotating electrical machine 10 of the present embodiment is used, for example, as a drive source for an electric vehicle. The rotating electrical machine 10 holds a stator 11 that generates a rotating magnetic field, a rotor 12 that rotates by receiving the rotating magnetic field generated by the stator 11, a rotating shaft 13 that is provided coaxially with the rotor 12, and the stator 11. And a housing 14 that covers the rotor 12 and the outside of the stator 11, and a cooling circuit 15 that cools the rotor 12, the stator 11, and the like with a coolant.

  The stator 11 includes a substantially cylindrical stator core 16 formed by laminating a plurality of electromagnetic steel plates, and a coil 17 wound around an inner peripheral edge of the stator core 16. The coil 17 is composed of a U-phase, V-phase, and W-phase three-phase coil. The coil 17 of this embodiment is comprised by the segment coil used mutually connected. The segment coil is configured by a segment conductor having a pair of insertion portions that are inserted into slots (not shown) of the stator core 16 and a folded connection portion (not shown) that connects the insertion portions. An end of the pair of insertion portions opposite to the folded connection portion is a connection portion connected to another adjacent segment conductor.

  In the coil 17, a connecting portion of each segment conductor is arranged on one end side in the axial direction of the stator 11, and a folded connecting portion is arranged on the other end side in the axial direction of the stator 11. The connection portion and the turn-back connection portion protrude outward from each end portion in the axial direction of the stator 11 (exposed to the outside). In the present embodiment, the connecting portion side of the coil 17 constitutes the first coil end 18f, and the folded connecting portion side of the coil 17 constitutes the second coil end 18s. An external power line is connected to the first coil end 18f. The coil 17 is energized through a power line.

The rotor 12 includes a rotor core 19 that is integrally coupled to the outer surface of the rotating shaft 13, and a permanent magnet 20 that is disposed on the outer peripheral edge of the rotor core 19 so as to be spaced apart in the circumferential direction. The rotor 12 is formed in a substantially cylindrical shape by laminating a plurality of electromagnetic steel plates. The rotating shaft 13 is rotatably supported by the housing 14 via a bearing 21. The rotating shaft 13 rotates integrally with the rotor 12 as the rotor 12 receives the rotating magnetic field of the stator 11 and rotates.
In addition, the code | symbol 8 in a figure is an end surface board which is piled up on the electromagnetic steel plate of the both ends of the rotor 12, and pinches | interposes a some electromagnetic steel plate.

  Here, in the present embodiment, the rotating electrical machine 10 is integrally coupled to a housing such as another generator (rotating electrical machine) or a transmission at one end side in the axial direction of the housing 14 that covers the outside of the rotor 12 and the stator 11. ing. An annular end cover 22 that covers the other end side of the rotor 12 in the axial direction in a non-contact state is attached to the other end side in the axial direction of the housing 14 of the rotating electrical machine 10. In the case of this embodiment, the bearing 21 is held on the inner peripheral side of the end cover 22.

  The cooling circuit 15 is formed along the axial direction inside the rotary shaft 13, a pump device 23 that discharges the coolant, a coolant main passage 24 that supplies the coolant discharged from the pump device 23 to the rotating electrical machine 10, and the rotation shaft 13. Then, the in-shaft passage 25 into which the coolant is introduced from the coolant main passage 24 and the coolant introduced from the in-shaft passage 25 through the interior of the rotor 12 are supplied to the first coil end 18 f of the coil 17. A first passage 26 and a second passage 27 that branches from the coolant main passage 24 and supplies the coolant introduced from the coolant main passage 24 to the second coil end 18 s of the coil 17 are provided. The second passage 27 is provided with a valve device 28 that is an opening / closing adjustment unit that opens and closes the second passage 27 in accordance with the operating state of the rotating electrical machine 10.

  The pump device 23 is connected to the rotating shaft 13 of the rotating electrical machine 10 via a gear mechanism or the like, and is driven to rotate in conjunction with the rotating shaft 13. Therefore, the pump device 23 increases or decreases the discharge amount and the discharge pressure in conjunction with the rotation of the rotor 12 of the rotating electrical machine 10.

  The first passage 26 penetrates one end face plate 8 from one axial end portion of the axial passage 26a in the axial direction of the axial passage 26a in the vicinity of each permanent magnet 20 of the rotor 12 along the axial direction of the rotor 12. Then, a discharge port 26b that opens to the radially inner position of the first coil end 18f, and an introduction path 26c that communicates the in-axis path 25 of the rotary shaft 13 and the other axial end of the axial path 26a. Have. When the coolant is introduced from the coolant main passage 24 to the introduction passage 26 c of the first passage 26 during the rotation of the rotor 12, the coolant flows through the axial passage 26 a in the rotor 12, and on the one end side of the rotor 12. Injection is supplied from the discharge port 26b to the first coil end 18f. The coolant flowing through the first passage 26 in the rotor 12 mainly cools the heat generated by the permanent magnet 20, and the coolant supplied to the first coil end 18f generates heat generated by the first coil end 18f. Cool mainly.

  A part of the second passage 27 is formed in the end cover 22 of the housing 14. A closing plate 29 having substantially the same outer diameter as the inner end surface of the end cover 22 is attached to the inner end surface of the end cover 22 (the end surface facing the rotor 12). The second passage 27 is branched on the upstream side (upstream side of the first passage 26) of the coolant main passage 24 with respect to the connecting portion with the in-shaft passage 25 of the rotating shaft 13.

FIG. 2 is a view showing an end surface on the inner side in the axial direction of the end cover 22 in a state where the closing plate 29 is removed.
As shown in FIGS. 1 and 2, the end cover 22 is connected to the valve accommodating portion 30 constituting a part of the valve device 28 and one end of the valve accommodating portion 30 to the upstream portion of the second passage 27. An inlet 31, an annular groove 32 that is formed on the end surface of the end cover 22 and communicates with the other end of the valve housing 30, and extends radially from the outer periphery of the annular groove 32 and communicates with the outer periphery of the end cover 22. And a plurality of passage grooves 33 are provided. The plurality of passage grooves 33 are formed at equal intervals on the outer periphery of the end cover 22. In the case of the present embodiment, the plurality of passage grooves 33 form a radial passage (a part of the second passage 27) together with the end cover 22 in a state where the closing plate 29 is attached to the end cover 22.
A reference numeral 38 in FIG. 1 is a resolver that is fastened to the end cover 22 together with the closing plate 29 and detects the rotational speed of the rotor 12. When the resolver 38 is fixed to the end cover 22 together with the closing plate 29 as in the present embodiment, the resolver 38 can be installed in the housing 14 of the rotating electrical machine 10 in a compact manner.

  The valve device 28 serving as an opening / closing adjustment unit is accommodated in the valve accommodating portion 30 of the closing plate 29, and a spherical valve element 34 that closes the introduction port 31 from the valve accommodating portion 30 side, and the valve element 34 in the valve closing direction. And a spring 35 (biasing means) that biases in the direction of closing the introduction port 31. The valve body 34 closes the inlet 31 (second passage 27) while the pressure of the coolant in the coolant main passage 24 is less than the set pressure, and the pressure of the coolant in the coolant main passage 24. When the pressure exceeds the set pressure, the inlet 31 (second passage 27) is opened against the urging force of the spring 35. Therefore, the valve device 28 adjusts the open / close state of the second passage 27 in accordance with the coolant supply pressure in the coolant main passage 24.

FIG. 3 is a view showing a cross section similar to FIG. 1 of the rotating electrical machine 10 in a state in which the valve body 34 of the valve device 28 opens the second passage 27.
Hereinafter, with reference to FIG. 1 and FIG. 3, the cooling operation | movement according to the driving | running state of the rotary electric machine 10 is demonstrated.
While the rotational speed of the rotor 12 of the rotating electrical machine 10 is low, the pressure of the coolant in the coolant main passage 24 does not reach the set pressure, so that the valve body 34 of the valve device 28 is spring 35 as shown in FIG. The second passage 27 is closed by the urging force. For this reason, almost all of the coolant supplied from the pump device 23 to the coolant main passage 24 is introduced into the shaft passage 25 of the rotary shaft 13. The coolant introduced into the in-shaft passage 25 passes through the first passage 26 in the rotor 12 as shown by the arrow in FIG. 1, and passes through the first outlet 26 b in the axial direction of the rotor 12 to the first of the coil 17. One coil end 18f is supplied by injection. While the coolant flows in the first passage 26 of the rotor 12, the vicinity of the permanent magnet 20 of the rotor 12 is cooled, and further injected and supplied to the first coil end 18f. Cooling.
At this time, since the second passage 27 is closed by the valve body 34 of the valve device 28, a sufficient amount of coolant is supplied to the first passage 26 and the first coil end 18f.

Further, when the rotational speed of the rotor 12 of the rotating electrical machine 10 increases and the pressure of the coolant in the coolant main passage 24 becomes equal to or higher than the set pressure, the valve body 34 of the valve device 28 is moved to the spring 35 as shown in FIG. The second passage 27 is opened against the urging force. As a result, as indicated by the arrow in FIG. 3, a part of the coolant supplied to the coolant main passage 24 passes through the passage groove 33 of the second passage 27 and is directly injected into the second coil end 18s. Supplied. At this time, the coolant introduced from the coolant main passage 24 into the in-shaft passage 25 of the rotating shaft 13 is injected and supplied to the first coil end 18 f via the first passage 26 inside the rotor 12.
As a result, the rotor 12 of the rotating electrical machine 10 is cooled by the coolant, and the first coil end 18f and the second coil end 18s of the coil 17 are both cooled by the coolant.

  As described above, the rotating electrical machine 10 according to the present embodiment branches from the coolant main passage 24 separately from the first passage 26 that supplies the coolant to the first coil end 18f via the inside of the rotor 12. A second passage 27 for supplying the coolant to the second coil end 18 s is provided, and the second passage 27 is opened and closed by the valve device 28 in accordance with the operating state of the rotating electrical machine 10. Therefore, in the rotating electrical machine 10 of the present embodiment, a sufficient amount of coolant is supplied to the first coil end 18f that easily generates heat even at low speed rotation without increasing the output and capacity of the pump device 23. In addition, according to the rotation of the rotor 12, the inside of the rotor 12, the first coil end 18f, and the second coil end 18s can be appropriately cooled by the coolant.

  Further, in the rotating electrical machine 10 of the present embodiment, the second passage 27 is branched from the coolant main passage 24 on the upstream side of the first passage 26. For this reason, the coolant that is not warmed by the heat of the rotor 12 can be supplied to the second coil end 18 s of the coil 17. Therefore, when this configuration is adopted, the second coil end 18s of the coil 17 can be efficiently cooled.

  Moreover, in the rotary electric machine 10 of this embodiment, the valve device 28 which is an opening / closing adjustment unit is configured to adjust the opening / closing state of the second passage 27 according to the supply pressure of the coolant. For this reason, when this embodiment is adopted, the second passage 27 can be opened in a state in which the supply pressure of the coolant is sufficiently increased, and the coolant is stabilized from the second passage 27 to the second coil end 18s. Can be supplied.

  Further, in the rotating electrical machine 10 of the present embodiment, the coolant main passage 24 is connected to a pump device 23 in which the coolant discharge pressure increases or decreases in conjunction with the rotation of the rotor 12. For this reason, when the rotary electric machine 10 of this embodiment is employ | adopted, supply of the cooling fluid to the 2nd channel | path 27 can be increased according to the increase in the rotational speed of the rotor 12, without using complicated control. it can.

  In particular, in the rotary electric machine 10 of the present embodiment, the opening / closing adjustment unit is configured by the valve device 28 in which the valve body 34 urged in the valve closing direction is opened according to the pressure of the coolant in the coolant main passage 24. ing. For this reason, the opening / closing adjustment unit can be configured with a simple configuration that can be miniaturized. Therefore, when this embodiment is adopted, it is possible to reduce the size of the rotating electrical machine 10 and reduce the product cost.

  In the rotating electrical machine 10 of the present embodiment, an end cover 22 that covers the end of the rotor 12 in the axial direction in a non-contact state is provided on the end of the rotor 12 in the axial direction. A plurality of passage grooves 33 that extend radially outward in the radial direction are formed on the end face facing the side 12. The closing plate 29 is coupled to the end of the end cover 22 facing the rotor 12, and the passage groove 33 and the closing plate 29 of the end cover 22 constitute a part of the second passage. For this reason, a passage groove 33 is formed in the end cover 22 that covers the end of the rotor 12 in the axial direction, and a part of the second passage 27 can be easily formed by simply connecting the closing plate 29 to the end cover 22. Can be formed. Therefore, when the configuration of the present embodiment is adopted, it is possible to reduce the size of the rotating electrical machine 10 and reduce the product cost by simplifying the structure.

  In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary.

DESCRIPTION OF SYMBOLS 10 ... Rotating electrical machine 11 ... Stator 12 ... Rotor 13 ... Rotating shaft 17 ... Coil 18f ... 1st coil end 18s ... 2nd coil end 20 ... Permanent magnet 22 ... End part cover 23 ... Pump apparatus 24 ... Coolant main passage 26 ... 1st channel | path 27 ... 2nd channel | path 28 ... Valve apparatus (opening-closing adjustment part)
29 ... Closure plate 33 ... Passage groove 34 ... Valve element

Claims (6)

A plurality of permanent magnets disposed on the outer periphery, and a rotor that rotates integrally with the rotation shaft;
A stator wound with a coil and disposed on the radially outer side of the rotor;
A coolant main passage for supplying coolant,
The first coil end of the coil is disposed so as to be exposed on one end side in the axial direction of the rotor, and the second coil end of the coil is disposed so as to be exposed on the other end side in the axial direction of the rotor. In electric
A first passage for supplying the coolant supplied to the coolant main passage to the first coil end via the rotor;
A second passage for branching from the coolant main passage and supplying the coolant to the second coil end;
An electric rotating machine further comprising: an opening / closing adjustment unit that opens and closes the second passage according to an operating state.   2. The rotating electrical machine according to claim 1, wherein the second passage is branched from the coolant main passage on the upstream side of the first passage.   3. The rotating electrical machine according to claim 1, wherein the opening / closing adjustment unit adjusts an opening / closing state of the second passage in accordance with a supply pressure of the coolant.   The rotating electrical machine according to claim 3, wherein the coolant main passage is connected to a pump device that increases or decreases a discharge pressure of the coolant in conjunction with rotation of the rotor.   The said opening / closing adjustment part is comprised by the valve apparatus by which the valve body urged | biased in the valve closing direction is valve-opened according to the pressure of the cooling fluid of the said cooling fluid main channel | path. The rotating electrical machine according to any one of 4. On the other end side in the axial direction of the rotor, an end cover that covers the other end side in the axial direction of the rotor in a non-contact state is provided,
The end cover has a plurality of passage grooves extending radially outwardly on an end face facing the rotor,
A closing plate is coupled to an end of the end cover facing the rotor,
6. The rotating electrical machine according to claim 1, wherein a part of the second passage is configured by the passage groove and the closing plate of the end cover.

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