JP2018129944A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine capable of supplying a cooling liquid across an axial direction of a coil end and enhancing a cooling effect.SOLUTION: To through holes 51, 61 penetrating end face plates 50, 60 in an axial direction, a coolant guide 70 that ejects a coolant toward a coil end 15a is connected. The coolant guide 70 has a coolant inlet portion 71, an elongated hole shaped coolant outlet portion 72 which opens so as to face the coil end, and a coolant flow path 73 connecting the coolant inlet portion 71 and the coolant outlet portion 72. At the coolant outlet portion 72, a wall surface portion 72c connecting one end portion and the other end portion of the elongated hole shape is inclined with respect to the end surface plate 50.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotating electrical machine that cools a coil end with a coolant.

  In recent years, vehicles equipped with a rotating electrical machine as a power source, such as electric vehicles and hybrid vehicles, have been developed. In such a rotating electrical machine, a rotor having a permanent magnet fixed to an inner peripheral portion of a stator core around which a stator coil is wound is rotatably supported.

  When the rotating electrical machine operates, the stator core and the stator coil generate heat. In order to suppress this heat generation, there is known a cooling system in which a coolant is ejected from the end face plates disposed at both ends of the rotor core via the inside of the shaft toward the coil ends of the stator core.

  In such a cooling method, a coolant such as ATF (Automatic transmission fluid) introduced via the inside of the shaft is ejected from the end face plate toward the coil end of the stator coil. A plurality of coolant jets are provided (see, for example, Patent Document 1). As a result, the cooling liquid is ejected from the cooling liquid ejection port, which varies depending on the rotational speed of the rotor core, to the coil end.

JP 2009-273284 A

  However, in such a cooling-type rotating electrical machine that ejects the coolant from the end face plate of the rotor toward the coil end, only a part of the coil end is selectively cooled according to the rotational speed of the rotor core. In addition, since the coolant cannot be supplied along the axial direction of the coil end, it has been difficult to sufficiently cool the coil end.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a rotating electrical machine that can supply a cooling liquid along the axial direction of a coil end and enhance a cooling effect.

In order to achieve the above object, the invention according to claim 1
An annular stator core (for example, a stator core 13 in an embodiment described later) formed with a plurality of slots (for example, a slot 14 in an embodiment described later), and a coil (for example, in an embodiment described later) A stator having a stator coil 15) (for example, a stator 10 in an embodiment described later),
A rotor core (for example, a rotor core 41 in an embodiment described later) rotatably disposed on the inner diameter side of the stator core, and an end face plate (for example, an end in an embodiment described later) disposed on at least one axial end surface of the rotor core. A rotating electrical machine (e.g., rotating electrical machine 1 in an embodiment described later) including a rotor (e.g., rotor 40 in an embodiment described later) having a face plate 50, 60),
In the coil, coil ends (for example, coil ends 15a and 15b in the embodiments described later) protrude from the axial end surfaces (for example, axial end surfaces 13a and 13b in the embodiments described later) of the stator core,
The end face plate has a through hole penetrating in the axial direction (for example, through holes 51 and 61 in the embodiments described later),
Connected to the through hole is a coolant guide (for example, a coolant guide 70 in an embodiment described later) that ejects coolant toward the coil end.
The coolant guide includes a coolant inlet portion (for example, a coolant inlet portion 71 in an embodiment described later) that communicates with the through hole, and an elongated hole-shaped coolant outlet portion that opens to face the coil end. (For example, a coolant outlet portion 72 in the embodiment described later), a coolant channel connecting the coolant inlet portion and the coolant outlet portion (for example, a coolant channel 73 in the embodiment described later), Have
In the coolant outlet portion, a wall surface portion (for example, one end portion 72a in the embodiment described later) and the other end portion (for example, the other end portion 72b in the embodiment described later) are connected. The wall surface portion 72c) in the embodiment described later is inclined with respect to the end face plate.

The invention according to claim 2 is the rotating electrical machine according to claim 1,
A plurality of the coolant guides are provided at equal intervals in the circumferential direction.

The invention according to claim 3 is the rotating electrical machine according to claim 1 or 2,
The coil end is inclined in a predetermined direction with respect to the end face plate at least each coil on the innermost diameter side when viewed from the radially inner side,
The inclination angle of the wall surface portion of the coolant outlet portion with respect to the end face plate (for example, the inclination angle α in an embodiment described later) is the inclination angle of the coil with respect to the end face plate (for example, the inclination angle β1 in the embodiment described later). , Β2).

The invention according to claim 4 is the rotating electrical machine according to any one of claims 1 to 3,
The cooling liquid inlet has an elongated hole shape,
The coolant guide is attached so that the elongated hole shape of the coolant inlet portion extends in the circumferential direction,
The coolant guide is formed so as to be twisted from the coolant inlet portion toward the coolant outlet portion, so that the coolant flow path is smoothly curved.

The invention according to claim 5 is the rotating electrical machine according to any one of claims 1 to 4,
The coolant guide is formed of a resin member.

The invention according to claim 6 is the rotating electrical machine according to any one of claims 1 to 5,
Cooling for connecting a coolant introduction part (for example, a coolant introduction part 43 in an embodiment described later) and the through hole provided in a rotor shaft (for example, a rotor shaft 42 in an embodiment described later) to the rotor core. A liquid introduction path (for example, a coolant introduction path 44 in an embodiment described later) is formed.

The invention according to claim 7 is the rotating electrical machine according to any one of claims 1 to 6,
The end plate includes a first end plate (for example, an end plate 50 in an embodiment described later) disposed on one axial end surface of the rotor core and a second end plate (for example, the other end plate disposed on the other axial end surface). An end face plate 60) in an embodiment described later,
The coolant guide is provided on both the first end face plate and the second end face plate.

  According to the first aspect of the present invention, the coolant guide for ejecting the coolant toward the coil end is connected to the through hole of the end face plate, and the one end and the other end of the long hole shape are connected at the coolant outlet. Since the wall surface portion is inclined with respect to the end face plate, the coolant guided to the wall surface portion has an axial speed component by being pushed by the wall surface portion in addition to the radial speed component due to centrifugal force. Thus, since the cooling liquid ejected along the wall surface portion of the cooling liquid outlet portion has the axial velocity component, the cooling liquid can be supplied over the axial direction of the coil end, and the cooling effect can be enhanced.

  According to the second aspect of the present invention, since a plurality of coolant guides are provided at equal intervals in the circumferential direction, the coolant can be continuously supplied to the coil ends as the rotor rotates.

  According to the invention of claim 3, since the inclination angle of the wall surface portion of the coolant guide is substantially equal to the inclination angle of each coil at least on the innermost diameter side of the coil end, the coolant is introduced into the gap between the coils constituting the coil end. By entering, the cooling effect can be further enhanced.

  According to the invention of claim 4, since the coolant guide is formed so as to be twisted from the coolant inlet portion toward the coolant outlet portion, the coolant passage is smoothly curved. It can be discharged smoothly.

  According to the invention of claim 5, since the coolant guide is formed by the resin member, the weight of the rotating electrical machine can be avoided even when the coolant guide is attached.

  According to the sixth aspect of the present invention, the rotor core is formed with the coolant introduction path for connecting the coolant introduction portion provided in the rotor shaft and the through hole, so that the coil cooling by the axial lubrication is possible. Become.

  According to the invention of claim 7, since the coolant guide is provided on both the first end face plate and the second end face plate, the coil ends on both sides can be appropriately cooled.

It is a perspective view of the rotary electric machine of one Embodiment of this invention. It is a front view of one coil end of a stator. It is a perspective view of the other coil end of a stator. It is a perspective view of a coil segment group in which four segment coils are aligned in one row. It is sectional drawing of the rotary electric machine which shows the flow of a cooling fluid. (A) It is a perspective view of a coolant guide, (b) It is a side view of the coolant guide attached to the end surface board. It is sectional drawing of the AA line of FIG.6 (b). It is the fragmentary perspective view of the rotary electric machine seen from one coil end side. It is the fragmentary perspective view of the rotary electric machine seen from the other coil end side. It is a figure which shows the inclination of the coil end seen from radial direction inner side.

  Hereinafter, a rotating electrical machine according to an embodiment of the present invention will be described with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIGS. 1 to 3, the rotating electrical machine 1 according to the present embodiment is a so-called inner rotor type rotating electrical machine including a stator 10 and a rotor 40 disposed on an inner peripheral portion of the stator 10.

  The stator 10 includes a stator core 13 in which a plurality of slots 14 penetrating in the axial direction are arranged at predetermined intervals in the circumferential direction, and a stator of a plurality of phases (for example, U phase, V phase, W phase) accommodated in the slots 14. A coil 15.

  As shown in FIG. 4, the stator coil 15 includes a pair of leg portions 21 a and 21 b extending in parallel with each other, and a connecting portion 22 that connects the leg portions 21 a and 21 b at one end portion, A plurality of substantially U-shaped coil segments 23 composed of rectangular wires 30 having a rectangular cross section are formed of a plurality of coil segment groups 20 that are arranged in a line every four.

  As shown in FIG. 2, one leg 21 a of each coil segment 23 is inserted into a radially inner portion of one slot 14, and the other leg 21 b is separated from one slot 14 by a predetermined number of slots. And inserted into the radially outer portion of the other slot 14 at the same position.

  When the plurality of coil segment groups 20 are arranged in the stator core 13, eight coil segments 23 are arranged in one slot 14 in the present embodiment. Further, as shown in FIG. 2, on one end side in the axial direction of the stator core 13, the connecting portions 22 of the plurality of coil segment groups 20 are continuous in the circumferential direction, and the connecting portions 22 adjacent in the circumferential direction are in the axial direction. The coil end 15a is formed by being arranged so as to partially overlap when viewed from above.

  Further, as shown in FIG. 3, at the other end side of the stator core 13 in the axial direction, the leg portions 21a and 21b protruding from the slot 14 are bent in the circumferential direction and joined to the coil of the same phase, thereby the coil end 15b. Is formed. In this embodiment, the leg 21a of the coil segment located on the innermost diameter side is bent to one side in the circumferential direction, and the legs of the two coil segments 23 located on the outer diameter side of the coil segment 23 located on the innermost diameter side. The portions 21a and 21a are bent toward the other side in the circumferential direction, and the leg portions 21a and 21b of the two coil segments 23 positioned on the outer diameter side are bent toward the one side in the circumferential direction.

  Returning to FIG. 1, the coil end 15 a on one end side protrudes in the axial direction from the axial end surface 13 a on one end side of the stator core 13, and the coil end 15 b on the other end side also has an axial end surface 13 b on the other end side of the stator core 13. Projecting axially from Further, since the coil end 15a is arranged with the four coil segments 23 in an aligned state, the four coil segments 23 are viewed from the radially inner side as shown in FIGS. Tilt in the same direction. On the other hand, in the coil end 15b, as shown in FIGS. 9 and 10, only the coil segment 23 located on the innermost diameter side is inclined in the same direction as viewed from the radially inner side. Note that a cooling liquid, which will be described later, can enter the gap between the inclined coil segments 23 of the coil ends 15a and 15b when viewed from the inside in the radial direction.

  As shown in FIG. 5, the rotor 40 disposed on the inner peripheral portion of the stator 10 includes a rotor core 41, a plurality of permanent magnets 45 accommodated in the rotor core 41, a pair of end face plates 50 and 60, and a rotor shaft 42. With.

  One end face plate 50 is disposed on the axial end face 41a on one end side of the rotor core 41 of the rotor 40, and the other end face plate 60 is disposed on the axial end face 41b on the other end side. A plurality of through holes 51 and 61 penetrating in the axial direction are provided on the outer peripheral side of the end face plates 50 and 60 at equal intervals along the circumferential direction. A coolant guide 70 that ejects coolant toward the coil end 15a is connected to the through holes 51 and 61. The coolant guide 70 is formed of a resin member separately from the end face plates 50 and 60 and is fixed to the end face plates 50 and 60.

  In the rotor core 41, a coolant introduction path 44 is formed so as to connect the coolant introduction part 43 provided in the rotor shaft 42 and the through holes 51 and 61.

  As shown in FIGS. 6 and 7, the coolant guide 70 includes a coolant inlet portion 71 that communicates with the through holes 51 and 61, a coolant outlet portion 72 that opens to face the coil ends 15 a and 15 b, and A coolant flow path 73 connecting the coolant inlet portion 71 and the coolant outlet portion 72. The coolant guide 70 is formed so as to be twisted in the rotational direction from the coolant inlet portion 71 toward the coolant outlet portion 72, so that the coolant channel 73 is twisted radially outward from the axial direction. Is smoothly curved.

  The coolant inlet portion 71 has a long hole shape, and is attached to the surface H of the end face plates 50 and 60 so that the long hole shape extends in the circumferential direction.

  The coolant outlet portion 72 has an elongated hole shape, like the coolant inlet portion 71, and opens toward the radially outer side so as to face the coil ends 15a and 15b. A wall surface portion 72 c connecting the end portions 72 b is inclined with respect to the surface H of the end surface plates 50 and 60.

  Specifically, as shown in FIG. 10, the inclination angle at which the wall surface portion 72c of the coolant outlet portion 72 inclines with respect to the surface H of the end face plate 50 is α1, and is arranged in each slot 14 constituting the coil end 15a. If the inclination angle at which the four coil segments 23 on the inner diameter side are inclined with respect to the surface H of the end face plate 50 is β1, the inclination angle α1 is formed to be substantially equal to the inclination angle β1.

  Similarly, the wall surface portion 72c of the coolant outlet portion 72 has an inclination angle α2 with respect to the surface H of the end face plate 60, and the coil segment 23 on the innermost diameter side of each slot constituting the coil end 15b is on the surface H of the end face plate 50. When the inclination angle to be inclined is β2, the inclination angle α2 is formed to be substantially equal to the inclination angle β2. Note that the inclination angle β1 and the inclination angle β2 may be the same or different. If the inclination angle β1 and the inclination angle β2 are equal, the inclination angle α1 and the inclination angle α2 are also equal, and the inclination angle β1 and the inclination angle β2 are equal. If they are different, the inclination angle α1 and the inclination angle α2 are also different.

  As described above, the wall surface portion 72c of the coolant outlet portion 72 is inclined with respect to the surface H of the end face plate 60, whereby the coolant guided to the wall surface portion 72c is axially added to the radial velocity component due to centrifugal force. With a velocity component of That is, as shown in FIG. 6B, the coolant discharged from the coolant outlet portion 72 is pushed by the wall surface portion 72c and has an axial speed component regardless of the rotational speed.

Next, the function of the coolant guide 70 according to the embodiment of the present invention will be described in detail.
As shown by the white arrows in FIGS. 8 to 10, when electric power is supplied to the stator 10 and the rotor 40 rotates, the coolant as ATF is provided on the rotor shaft 42 as shown in FIG. 5. It passes through the coolant introduction part 43 and flows into the coolant introduction path 44 of the rotor core 41.

  The coolant flowing into the coolant introduction path 44 is divided into left and right, passes through the through holes 51 and 61 of the end face plates 50 and 60, and is guided to the coolant inlet portion 71 of the coolant guide 70, respectively. .

  As shown by the black arrows in FIGS. 6 and 7, the direction of the coolant that has reached the coolant inlet 71 is smoothly changed so as to be twisted radially outward from the axial direction in the coolant channel 73. A radial velocity component due to centrifugal force is added. Subsequently, the cooling liquid is ejected toward the coil ends 15a and 15b from the cooling liquid outlet portion 72 that opens outward in the radial direction.

  At this time, the coolant outlet portion 72 has a long hole shape, and a wall surface portion 72c connecting the one end portion 72a and the other end portion 72b of the long hole shape is inclined with respect to the surface H of the end face plates 50 and 60. Therefore, the coolant discharged from the coolant outlet portion 72 is pushed by the wall surface portion 72c and has an axial speed component regardless of the rotational speed. Thereby, the cooling liquid discharged from the cooling liquid outlet part 72 spreads in the axial direction in addition to the movement outward in the radial direction by the centrifugal force.

  Further, as described above, the inclination angles α1 and α2 of the coolant outlet portion 72 with respect to the axial direction are formed to be substantially equal to the inclination angles β1 and β2 of the coil segment 23 with respect to the axial direction. Therefore, the cooling liquid discharged from the cooling liquid outlet 72 is sprayed at the same angle as the inclination angles β1 and β2 of the coil segment 23.

  Thereby, the cooling liquid discharged from the cooling liquid outlet 72 is supplied along the gap between the coil segments 23 having the inclination angles β1 and β2, and the coil segment 23 on the outer diameter side by the velocity component due to the axial direction and centrifugal force. It gradually spreads from the gap. Therefore, the coolant can be supplied over the axial direction of the coil end 15a, the coolant can be sprayed over a wide range of the coil ends 15a and 15b, and the stator coil 15 can be appropriately cooled.

  As described above, according to the rotating electrical machine 1 according to the present embodiment, the coolant guide 70 that ejects the coolant toward the coil ends 15a and 15b is connected to the through holes 51 and 61 of the end face plates 50 and 60. Since the wall surface portion 72c connecting the one end portion 72a and the other end portion 72b of the elongated hole shape in the coolant outlet portion 72 is inclined with respect to the end surface plates 50, 60, the coolant guided to the wall surface portion 72c is In addition to the radial speed component caused by the centrifugal force, it has an axial speed component by being pushed by the wall surface portion 72c. In this way, the cooling liquid ejected along the wall surface portion 72c of the cooling liquid outlet portion 72 has the velocity component in the axial direction, so that the cooling liquid can be supplied in the axial direction of the coil ends 15a and 15b, and the cooling effect can be obtained. Can be increased.

  Further, since a plurality of coolant guides 70 are provided at equal intervals in the circumferential direction, the coolant can be continuously supplied to the coil ends 15 a and 15 b as the rotor 40 rotates.

  In addition, the inclination angles α1 and α2 of the wall surface portion 72c of the coolant guide 70 are substantially equal to the inclination angles β1 and β2 of the coils at least on the innermost diameter side of the coil ends 15a and 15b, and thus constitute the coil ends 15a and 15b. The cooling effect can be further enhanced by the coolant entering the gaps of the coils.

  Further, since the coolant guide 70 is formed so as to be twisted from the coolant inlet portion 71 toward the coolant outlet portion 72, the coolant passage 73 is smoothly curved, so that the coolant is discharged smoothly. it can.

  Further, since the coolant guide 70 is formed of a resin member, the rotating electrical machine 1 can be prevented from becoming heavy even when the coolant guide 70 is attached.

  In addition, the rotor core 41 is formed with a coolant introduction path 44 that connects the coolant introduction portion 43 provided in the rotor shaft 42 and the through holes 51 and 61, so that coil cooling by axial lubrication is possible. Become

  Furthermore, since the coolant guide 70 is provided in both the end surface plates 50 and 60, the coil ends 15a and 15b on both sides can be appropriately cooled. The coolant guide 70 is not necessarily provided on the end face plates 50 and 60 on both sides, and may be provided on either one of the end face plates 50 and 60.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
For example, in the present embodiment, the coolant guide 70 is separated from the end face plates 50 and 60, but may be formed integrally with the end face plates 50 and 60.

  The coolant outlet portion 72 of the coolant guide 70 has an elongated hole shape, and the elongated hole shape includes an ellipse, a rectangle, and the like.

  In the present embodiment, the stator coil 15 is configured by the coil segment 23 divided into a plurality of twisted U-shaped conductors (segment conductors). However, in other winding structures, the cooling liquid is also used. By having a velocity distribution in the axial direction, it is possible to obtain a high cooling effect as well.

  In the present embodiment, the coolant guide 70 is made of resin, but may be formed of other members such as metals.

DESCRIPTION OF SYMBOLS 1 Rotating electrical machine 10 Stator 13 Stator core 13a Axial end surface 13b Axial end surface 14 Slot 15 Stator coil 15a Coil end 15b Coil end 40 Rotor 41 Rotor core 42 Rotor shaft 43 Coolant introduction path 44 Coolant introduction path 50 End plate (first end) Face plate)
51 Through-hole 60 End face plate (second end face plate)
61 Through hole 70 Coolant guide 71 Coolant inlet part 72 Coolant outlet part 72a One end part 72b Other end part 72c Wall part 73 Coolant flow path α Inclination angle β1 Inclination angle β2 Inclination angle

Claims (7)

A stator having an annular stator core formed with a plurality of slots, and a coil inserted into the slots;
A rotary electric machine comprising: a rotor having a rotor core rotatably disposed on an inner diameter side of the stator core; and an end surface plate disposed on at least one axial end surface of the rotor core,
The coil has a coil end protruding from the axial end surface of the stator core,
The end face plate has a through hole penetrating in the axial direction;
A coolant guide that ejects coolant toward the coil end is connected to the through hole,
The coolant guide includes a coolant inlet portion communicating with the through hole, a long hole-shaped coolant outlet portion opening to face the coil end, the coolant inlet portion, and the coolant outlet portion. A coolant flow path connecting the
The rotating electrical machine in which the wall surface portion connecting the one end portion and the other end portion of the elongated hole is inclined with respect to the end face plate in the coolant outlet portion. The rotating electrical machine according to claim 1,
A plurality of the cooling liquid guides are provided at equal intervals in the circumferential direction. The rotating electrical machine according to claim 1 or 2,
The coil end is inclined in a predetermined direction with respect to the end face plate at least each coil on the innermost diameter side when viewed from the radially inner side,
A rotating electrical machine in which an inclination angle of the wall surface portion of the coolant outlet portion with respect to the end face plate is substantially equal to an inclination angle of the coil with respect to the end face plate. The rotating electrical machine according to any one of claims 1 to 3,
The cooling liquid inlet has an elongated hole shape,
The coolant guide is attached so that the elongated hole shape of the coolant inlet portion extends in the circumferential direction,
The rotating electrical machine, wherein the coolant guide is formed to be twisted from the coolant inlet portion toward the coolant outlet portion, so that the coolant flow path is smoothly curved. The rotating electrical machine according to any one of claims 1 to 4,
The rotating electrical machine, wherein the coolant guide is formed of a resin member. It is a rotary electric machine of any one of Claims 1-5,
A rotating electrical machine in which the rotor core is formed with a coolant introduction path that connects a coolant introduction portion provided on a rotor shaft and the through hole. The rotating electrical machine according to any one of claims 1 to 6,
The end face plate includes a first end face plate disposed on one axial end face of the rotor core, and a second end face plate disposed on the other axial end face,
The coolant guide is a rotating electrical machine provided on both the first end face plate and the second end face plate.

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