JP6825227B2 - Rotating machine - Google Patents

Description

The present invention relates to a rotary electric machine that can be cooled by using a refrigerant liquid.

Conventionally, in a rotary electric machine in which the permanent magnets and coils of the rotary electric machine are cooled by using a refrigerant liquid such as oil, a technique for suppressing the infiltration of the refrigerant liquid into the air gap between the rotor and the stator is known. (See, for example, Patent Document 1).
In this conventional technique, a refrigerant liquid discharge port for discharging a refrigerant liquid from the inside of the rotor core, and a refrigerant liquid discharge unit provided at a predetermined position between the refrigerant liquid discharge port and the outer peripheral surface of the rotor core over the entire circumference of the rotor. And have. The refrigerant liquid discharge portion has a concave portion that is retracted inward in the radial direction and a convex portion that protrudes on the refrigerant liquid discharge port side of the concave portion.

Therefore, in the above-mentioned prior art, the refrigerant liquid discharged from the refrigerant liquid discharge port and heading toward the outer periphery of the rotor does not move from the convex portion to the concave portion, is prevented from flowing into the air gap, and flows into the air gap. It is possible to prevent the refrigerant liquid from becoming a resistance to the rotational force of the rotor.

Japanese Unexamined Patent Publication No. 2009-118686

However, in the above-mentioned conventional technique, it is not possible to prevent the refrigerant liquid from entering the air gap when the refrigerant liquid level in the lower part of the motor chamber rises, and there is a problem that the stirring loss due to this cannot be prevented. It was.
That is, the refrigerant liquid (oil) scattered from the rotor rotating at high speed repeatedly collides with the oil sump in the housing and the lower part of the motor chamber, so that air bubbles are mixed in the refrigerant liquid. As a result, the apparent volume of the refrigerant liquid (oil) increases by the amount of air bubbles mixed in, and the refrigerant liquid level in the oil pool at the lower part of the motor chamber rises. Therefore, the refrigerant liquid level, which was located below the air gap surface in the initial state, may rise above the air gap, and the refrigerant liquid may infiltrate into the air gap.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotary electric machine capable of suppressing the infiltration of the refrigerant liquid into the air gap even when the refrigerant liquid level in the lower part of the motor chamber rises. To do.

In the rotary electric machine of the present invention, the rotor shaft ends, which are both ends in the axial direction of the rotor, are arranged closer to the housing than the end faces in the axial direction of the stator, and the rotor shaft ends are arranged. The rotary electric machine is characterized by having a large diameter portion located in the outer diameter direction with respect to the inner circumference of the stator core.

In the rotary electric machine of the present invention, since the large diameter portion of the rotor shaft end is arranged and rotates so as to cover the axial end of the air gap, the refrigerant liquid is air even when the refrigerant liquid level rises. The large diameter part suppresses the inflow into the gap. Therefore, the inflow of the refrigerant liquid into the air gap is reduced, the stirring loss of the rotor is reduced, and the motor efficiency is improved.

It is sectional drawing of the rotary electric machine of Embodiment 1. FIG. It is an exploded sectional view of the rotary electric machine of Embodiment 1. FIG. It is sectional drawing of the rotary electric machine of Embodiment 1, and shows the sectional view of the position of line S3-S3 of FIG. It is sectional drawing of the rotary electric machine of Embodiment 1, and shows the sectional view of the position of line S4-S4 of FIG. It is sectional drawing of the rotary electric machine of Embodiment 1, and shows the sectional view of the position of line S5-S5 of FIG. It is explanatory drawing of the large diameter convex part of the end plate of the rotary electric machine of Embodiment 1, (a) is the figure which shows the rotation direction of an end plate, (b) is the large diameter convex part shown in the K part of (a). A diagram showing an example, (c) is a diagram showing another example of the large-diameter convex portion shown in the K portion of (a).

Hereinafter, the best mode for realizing the rotary electric machine of the present invention will be described based on the embodiment shown in the drawings.
(Embodiment 1)
First, the structure of the rotary electric machine A including the rotary electric machine of the first embodiment will be described.
FIG. 1 is a cross-sectional view showing a rotary electric machine A.
The rotary electric machine A includes a housing 1, a stator 2, and a rotor 3.

The housing 1 includes a housing body 11 having a substantially bottomed cylindrical shape and a cover 12 having a substantially disk shape that closes an opening at one end of the housing body 11 in the axial direction, and a motor chamber 13 is formed therein. The housing body 11 includes a cylindrical portion 11a and a disk-shaped cover portion 11b that closes an opening at one end of the cylindrical portion 11a. Further, the axial center portion of the cover portion 11b has a bearing 11c and a sealing material 11d on the motor chamber 13 side thereof. Further, the cover 12 also has a bearing 12c at a position coaxial with the bearing 11c at the axial center portion, and has a sealing material 12d on the motor chamber 13 side thereof.

As shown in FIG. 3, the stator 2 includes a stator core 21 formed in an annular shape, and teeth 22 are projected in the inner diameter direction at regular intervals in the circumferential direction on the inner circumference of the stator core 21. Further, the coil 24 is wound around the teeth 22 by being housed in a slot 23 provided between the teeth 22. The stator core 21 is configured by laminating a large number of ring-shaped steel plates in a direction along the central axis.

Then, as shown in FIG. 1, the outer circumference of the stator core 21 is fixed to the inner circumference of the cylindrical portion 11a of the housing body 11. A plurality of fins 11f for heat dissipation are formed on the outer periphery of the cylindrical portion 11a so as to project in the outer diameter direction.
Further, inside the stator core 21, a rotor 3 is arranged between the outer circumference thereof and the inner circumference of the stator core 21 via an air gap 5. That is, the rotary electric machine A obtains rotational power by the electromagnetic action of the coil 24 described above and the permanent magnet (not shown) of the rotor 3.

The rotor 3 includes a rotor shaft 31 and a rotor core 32.
The rotor shaft 31 is arranged along the central axis of the cylindrical portion 11a of the housing 1, and both ends thereof are rotatably supported by bearings 11c and 12c.

The rotor core 32 is fixed to the outer circumference of the rotor shaft 31, and has a rotor core body 32a in which a plurality of metal plates are vertically laminated and an end plate 32ep which is arranged at both ends of the rotor core body 32a in the axial direction to support the rotor core body 32a. , 32 ep. The rotor core 32 is internally provided with a plurality of permanent magnets (not shown) at intervals in the circumferential direction.

Further, the rotor 3 is formed so that the dimension in the axial direction is larger than that of the stator core 21. Therefore, both end plates 32 ep and 32 ep are located closer to the housing 1 (cover portion 11b, cover 12) than the end faces in the axial direction of the stator core 21.

The rotary electric machine A having the above configuration can function as an electric motor by energizing the coil 24, and can also function as a generator that generates electricity by a driving force transmitted from the outside to the rotary electric machine A. is there.

Next, the cooling structure of the rotary electric machine A will be described.
The rotor 3 includes a refrigerant supply path 4 for supplying a refrigerant liquid from the outside of the rotary electric machine A. That is, the rotary electric machine A has a structure in which the refrigerant liquid is circulated to cool the permanent magnet and the coil 24. Cooling oil can be used as the refrigerant liquid, but the refrigerant liquid is not limited to this. Further, the refrigerant liquid is supplied to the rotary electric machine A by the pump O / P, and is sucked into the pump O / P from the refrigerant reservoir 13a at the lower part of the motor chamber 13.

The refrigerant supply path 4 includes a rotary axis flow path 41, a radial flow path 42, and a rotor axial flow path 43.
The rotary axis flow path 41 extends axially from the refrigerant inlet 41a at one end of the rotor shaft 31 along the central axis of the rotor shaft 31.

The radial flow path 42 is a flow path extending from the rotary axis flow path 41 through the rotor shaft 31 and the rotor core 32 in the outer diameter direction, and includes a shaft through hole 42a and a rotor core radial flow path 42b.

The shaft through hole 42a is formed so as to penetrate the rotor shaft 31 in the outer diameter direction at a position substantially coincident with one end of the rotor core 32 in the axial direction in the rotor shaft 31 in the axial direction.

The rotor core radial flow path 42b is formed between the end plate 32ep of the rotor core 32 and the rotor core main body 32a. In the first embodiment, an axially recessed groove is formed in the end surface of the end plate 32ep in the outer radial direction. It is formed extending to.

The rotor core radial flow path 42b is formed in the vicinity of the outer peripheral portion of the rotor core 32 and penetrates the rotor core 32 in parallel with the central axis of the rotor 3 at the outer radial tip position of the rotor core radial flow path 42b. Both ends of the rotor core radial flow path 42b serve as refrigerant discharge ports 44, 44 in which the rotor axial flow path 43 is opened toward the motor chamber 13.

Further, the refrigerant discharge port 44 shown in FIG. 3 and the rotor core radial flow path 42b (not shown in FIG. 3) coaxial with the refrigerant discharge port 44 are provided at substantially equal intervals in the circumferential direction in the rotor core 32 (end plate 32 ep in the figure). In the embodiment, 8) is formed. Therefore, the same number of rotor core radial flow paths 42b (see FIG. 1) as the refrigerant discharge ports 44 shown in FIG. 4 are provided. That is, although the rotor core radial flow path 42b does not appear in FIG. 4, the rotary axis flow path 41 shown in FIG. 4 and the rotor core radial flow path 42b are formed so as to communicate with each other in the radial direction.

Further, as shown in FIGS. 3 and 5, a plurality of large-diameter convex portions 33 are formed on the outer peripheral portion of the end plate 32ep at regular intervals in the circumferential direction. That is, the outer peripheral portion of the end plate 32ep includes an arc-shaped portion 34 having an outer diameter smaller than the inner diameter of the stator core 21, and a large-diameter convex portion 33 protruding from the arc-shaped portion 34 in the outer diameter direction. It is formed in an uneven shape.

The top of the large-diameter convex portion 33 in the outer-diameter direction is located on the outer-diameter side of the inner circumference of the stator core 21, while the large-diameter convex portion 33 is located on the inner-diameter side of the coil 24 of the slot 23. Therefore, when the rotor 3 is rotated, the large-diameter convex portion 33 rotates so as to block the open portion 51 opened toward the motor chamber 13 at both ends in the axial direction of the air gap 5 without interfering with the coil 24.

Further, the circumferential interval of the large-diameter convex portion 33 is set to an integral multiple (twice in the present embodiment) of the circumferential interval of the slot 23 of the stator core 21.
Therefore, when assembling the rotor 3, as shown in FIG. 3, the arrow Y2 in FIG. 2 has the position in the circumferential direction of the large-diameter convex portion 33 aligned with the position in the circumferential direction of the slot 23 of the stator 2. As shown in, the inside of the stator core 21 can be moved in the axial direction.

The large-diameter portion 33 has a substantially trapezoidal shape symmetrical in the circumferential direction in FIGS. 3 and 5, but has a substantially triangular shape shown in FIG. 6 (b) and an arc shape shown in FIG. 6 (c). It is preferable to form in.
That is, in the large diameter portion 33 (b) shown in FIG. 6 (b) and the large diameter portion 33 (c) shown in FIG. 6 (c), the protruding side surface 33 a on the rotation direction side of the rotor 3 indicated by the arrow YR ends. It is formed with an inclination angle smaller than 90 degrees with respect to the arcuate portion 34 of the plate 32 ep. Specifically, the large-diameter convex portion 33 (b) shown in FIG. 6B has a substantially triangular shape in which the protruding side surface 33a on the rotation direction side forms an acute angle of inclination θ with respect to the tangential direction of the arcuate portion 34. Is formed in. The large-diameter convex portion 33 (c) shown in FIG. 6C is formed in a semicircular shape, and the protruding side surface 33a on the rotation direction side is inclined so as to rise in a gentle arc with respect to the arcuate portion 34. It is formed in a shape.

(Action of Embodiment 1)
Next, the operation of the first embodiment will be described.
When the rotary electric machine A is driven, the pump O / P is driven to supply the refrigerant from the refrigerant inlet 41a to the refrigerant supply path 4. The refrigerant liquid supplied to the refrigerant supply path 4 has a rotary axis flow path 41, a radial flow path 42, and a rotor axial flow path due to the discharge pressure of the pump O / P and the centrifugal force acting by the rotation of the rotor 3. It passes through 43 and scatters from the refrigerant discharge port 44 to the motor chamber 13. Further, the refrigerant liquid scattered in the motor chamber 13 falls into the refrigerant liquid reservoir 13a at the lower part of the motor chamber 13, is sucked by the pump O / P, and is again supplied to the refrigerant supply path 4 of the rotary electric machine A. repeat.

As the refrigerant liquid is circulated as described above, heat exchange can be performed with the permanent magnet of the rotor 3 and the coil 24 of the stator 2 to cool them.

By the way, when the rotor 3 rotates at a high speed, the refrigerant liquid (oil) scattered from the rotor 3 repeatedly collides with the refrigerant liquid pool 13a at the lower part of the housing 1 and the motor chamber 13, and air bubbles are mixed in the refrigerant liquid. ..

Then, since the apparent volume of the refrigerant liquid increases by the amount of the air bubbles mixed in, the liquid level of the refrigerant liquid pool 13a at the lower part of the motor chamber 13 rises. As a result, the liquid level located below the air gap 5 set between the stator 2 and the rotor 3 in the initial state may rise to a position higher than the air gap 5.

At this time, in the first embodiment, the large-diameter convex portion 33 formed on the end plate 32ep of the shaft end portion of the rotor 3 is arranged and rotates so as to cover the open portion 51 at the axial end portion of the air gap 5. .. Therefore, the large-diameter convex portion 33 prevents the refrigerant liquid from flowing into the air gap 5 from the refrigerant liquid pool 13a at the lower part of the motor chamber 13 where the liquid level has risen through the open portion 51. As a result, the inflow of the refrigerant liquid into the air gap 5 can be reduced, so that the stirring loss of the rotor 3 is reduced and the motor efficiency is improved.

(Effect of Embodiment 1)
The effects of the first embodiment are listed below.
1) The rotary electric machine of the first embodiment is
A stator 2 whose outer circumference is supported by the housing 1 and
A rotor 3 rotatably supported by the housing 1 and arranged inside the stator 2 via an air gap 5.
A refrigerant supply path 4 provided so that the refrigerant liquid supplied to the rotor 3 scatters as the rotor 3 rotates.
It is a rotary electric machine equipped with
The end plates 32ep as the rotor shaft ends, which are both ends in the axial direction of the rotor 3, are arranged closer to the cover portion 11b and the cover 12 of the housing 1 than the end faces in the axial direction of the stator 2. Being done
The end plate 32ep is provided with a large-diameter convex portion 33 located in the outer diameter direction with respect to the inner circumference of the stator core 21 of the stator 2.
Therefore, since the large-diameter convex portion 33 formed on the end plate 32ep covers the open portion 51 at the axial end of the air gap 5 and rotates, the liquid level of the refrigerant liquid pool 13a rises above the air gap 5. Also, it hinders the inflow of the refrigerant liquid into the air gap 5. As a result, the inflow of the refrigerant liquid into the air gap 5 can be reduced, so that the stirring loss of the rotor 3 is reduced and the motor efficiency is improved.

2) The rotary electric machine of the first embodiment is
At least one of the end plates 32ep and 32ep as the end of the rotor shaft has an arcuate portion 34 having an outer peripheral portion having a diameter smaller than the inner diameter of the stator core 21 and a large-diameter convex portion protruding from the arcuate portion 34 in the outer diameter direction. Formed in a concavo-convex shape with a portion 33,
The large-diameter convex portions 33 are equidistant in the circumferential direction and are formed at intervals that are integral multiples of the spacing between the slots 23 of the stator core 21.
Therefore, the rotor 3 can be assembled by the conventional method of inserting the rotor 3 into the stator 2 from one of the directions along the axial direction of the stator 2. Therefore, the manufacturing cost can be reduced as compared with the case where the end plates having a diameter larger than the inner diameter of the stator core 21 are assembled from both sides of the stator 2 by a procedure different from the conventional one.

3) The rotary electric machine of the first embodiment is
Both of the end plates 32 ep and 32 ep as the end portions of the rotor shaft are formed in the uneven shape.
Therefore, the end plates 32 ep and 32 ep can be shared, and a disk-shaped one having a diameter larger than the inner diameter of the stator core 21 is used for one end plate over the entire circumference, as compared with the case where different shapes are used. The number of points can be reduced and the manufacturing cost can be reduced.

4) The rotary electric machine of the first embodiment is
The protruding side surface 33a of the large-diameter convex portion 33 on the rotation direction side is formed in a shape that is gently inclined with respect to the arcuate portion 34.
Therefore, the resistance when the large-diameter convex portions 33 of the end plates 32 ep and 32 ep enter the refrigerant liquid can be reduced, so that the stirring loss of the rotor 3 is further reduced and the motor efficiency is improved.

Although the embodiment of the present invention has been described above, the specific configuration is not limited to this embodiment, and as long as it does not deviate from the gist of the invention according to each claim of the claims. Design changes and additions are allowed.

For example, in the embodiment, an example is shown in which both outer peripheral portions of the end plate are formed in an uneven shape. However, an end plate having an uneven outer peripheral portion shown in the embodiment may be applied to only one of the end plates, and a disk-shaped end plate having a diameter larger than the inner diameter of the stator core may be used for the other end plate. In this case, by inserting from the uneven end plate at the time of assembling, the rotor that has been assembled can be inserted into the conventional stator and assembled.

Further, in the embodiment, an example is shown in which the interval between the large diameter portions of the end plate having an uneven outer peripheral portion is twice the interval between the slots, but the interval is not limited to this. For example, the spacing of the large diameter portions may be the same as the spacing of the slots (1 times), or may be an integral multiple of 3 or more.

Alternatively, when assembling the rotor by using an assembling method that does not allow the large diameter portion to pass through the slots, the spacing between the large diameter portions can be arbitrarily set without being restricted by the slot spacing.
Further, the shape of the large-diameter convex portion as the large-diameter portion is not limited to the shapes shown in the embodiments (shapes of FIGS. 6 (b) and 6 (c)). For example, even if the protruding side surface is formed so as to rise in the normal direction of the arcuate portion or to have an obtuse angle than the normal line, the effect of suppressing the infiltration of the refrigerant liquid into the air gap can be obtained. ..

Further, when assembling the rotor, when an assembling method that does not allow the large diameter portion to pass through the slot is used, the end plates at both ends in the axial direction of the rotor are disc-shaped end plates having a diameter larger than the inner diameter of the stator core. Can also be used.

1 Housing 2 Stator 3 Rotor 4 Refrigerant supply path 5 Air gap 13 Motor chamber 21 Stator core 22 Teeth 23 Slot 24 Coil 32ep End plate (rotor shaft end)
33 Large-diameter convex portion 33a Protruding side surface 34 Arc-shaped portion 51 Open portion A Rotating electric machine

Claims (4)

With a stator whose outer circumference is supported by the housing,
With a rotor located inside the stator via an air gap and rotatably supported by the housing.
A refrigerant supply path provided so that the refrigerant liquid supplied to the rotor scatters as the rotor rotates.
It is a rotary electric machine equipped with
The end plates arranged at both ends in the axial direction of the rotor are axially oriented along the axial direction of the cylindrical portion of the housing body of the housing, rather than the end faces in the axial direction of the stator core of the stator. It is placed on the side close to the cover and the cover that closes the openings at both ends of the
Said end plates, Bei example a large diameter portion which is positioned radially outward of the inner periphery of the stator core of the stator,
At least one of the end plates is formed in a concavo-convex shape having an outer peripheral portion having an arcuate portion having a diameter smaller than the inner diameter of the stator core and the large diameter portion protruding from the arcuate portion in the outer diameter direction. A rotating electric machine characterized by being used . Te rotary electric machine smell of claim 1,
Before Kitai diameter is equal intervals in the circumferential direction, and the rotating electrical machine, characterized by being formed by an integer multiple of the interval containing interval and 1 of the stator core slot. In the rotary electric machine according to claim 2,
A rotary electric machine characterized in that both of the end plates have the outer peripheral portion formed in the uneven shape. In the rotary electric machine according to claim 2 or 3.
A rotary electric machine characterized in that the protruding side surface of the large-diameter portion on the rotation direction side is formed in a shape inclined at an inclination angle smaller than a right angle with respect to the arc-shaped portion.