JP2015104214A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the cooling performance of a rotary electric machine.SOLUTION: A rotary electric machine 1 includes: a frame 2; a stator 3 fixed to the inner side of the frame 2; a stator jacket 5 which is disposed between the frame 2 and the stator 3, the stator jacket 5 in which a second refrigerant passage 4 is formed; a rotor 6 which is disposed so as to face the stator 3 in a radial direction through a gap; a hollow rotary shaft 7 to which the rotor 6 is fixed, the rotary shaft 7 rotatably supported by a bearing 13; a fixed shaft 8 inserted into the rotary shaft 7; and a first refrigerant passage 9 formed between the rotary shaft 7 and the fixed shaft 8.

Description

  The disclosed embodiment relates to a rotating electrical machine.

  Patent Document 1 describes a motor cooling device including a stator core, a frame provided outside the stator core, and a frame cooling jacket through which a refrigerant passes between the stator core and the frame.

Japanese Patent No. 3538947

  Since the motor cooling device does not have a cooling structure on the rotor side, there is room for further improvement in cooling capacity.

  This invention is made | formed in view of such a problem, and it aims at providing the rotary electric machine which can raise cooling capacity.

  In order to solve the above-described problem, according to one aspect of the present invention, a rotor is fixed and a hollow rotating shaft rotatably supported by a bearing, and a fixed shaft inserted inside the rotating shaft, A rotating electrical machine having a first coolant channel formed between the rotating shaft and the fixed shaft is applied.

  According to the present invention, the cooling capacity of the rotating electrical machine can be increased.

It is an axial sectional view showing the whole composition of the rotation electrical machinery concerning an embodiment. It is an axial direction sectional view showing the whole composition of the rotation electrical machinery in the modification which formed the refrigerant channel in the turntable. It is an axial direction sectional view showing the whole composition of the rotation electrical machinery in the modification which provides the 1st refrigerant channel along the direction of an axis.

  Hereinafter, an embodiment will be described with reference to the drawings. In the following, for convenience of description of the configuration of the rotating electrical machine and the like, directions such as up and down, left and right are used as appropriate, but the positional relationship of the components of the rotating electrical machine and the like is not limited.

<Configuration of rotating electrical machine>
The overall configuration of the rotating electrical machine according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, the rotating electrical machine 1 includes a frame 2, a stator 3, a stator jacket 5, a rotor 6, a hollow rotary shaft 7, a hollow fixed shaft 8, and a first Refrigerant channel 9. A rotary table 20 for mounting a work (not shown) is attached to the other axial end of the rotary shaft 7 (upper end in FIG. 1). In this example, the rotating electrical machine 1 is configured as a direct drive type motor that directly rotates and drives a rotary table 20 that is a load object by a rotary shaft 7.

  The frame 2 is formed in a cylindrical shape. An anti-load side bracket 11 and a load side bracket 12 that close the respective openings are attached to one axial side (the lower side in FIG. 1) and the other axial side of the frame 2. The stator 3 is fixed to the inside of the frame 2, and the stator jacket 5 is disposed between the frame 2 and the stator 3.

  The rotor 6 has a plurality of permanent magnets 6a. The plurality of permanent magnets 6a are fixed to the outer peripheral surface of the rotating shaft 7 so that the longitudinal direction thereof is along the axial direction. The rotor 6 is disposed so as to face the stator 3 with a gap in the radial direction. The rotary shaft 7 is rotatably supported by the load side bracket 12 via a bearing 13 provided on the other axial side of the outer peripheral surface. For example, a cross roller bearing or the like is used as the bearing 13. As described above, the rotating shaft 7 is hollow, and the fixed shaft 8 is inserted inside thereof. The rotation shaft 7 and the fixed shaft 8 are configured to be slidable in the rotation direction. One end (the lower end in FIG. 1) of the fixed shaft 8 in the axial direction is fixed to the anti-load side bracket 11.

  Between the rotary shaft 7 and the fixed shaft 8, rotary contact seals 14 are provided on both sides in the axial direction. The rotary contact seal 14 can seal the refrigerant flowing through the first refrigerant flow path 9. In the present embodiment, the rotational contact seal 14 on one axial side (lower side in FIG. 1) is provided on the rotary shaft 7 side, and the rotational contact seal 14 on the other axial side (upper side in FIG. 1) is provided on the fixed shaft 8 side. It is done. The installation position of the rotary contact seal 14 is not limited to this, and both may be provided on the rotary shaft 7 side or the fixed shaft 8 side. The rotation contact seal 14 on the lower side may be provided on the fixed shaft 8 side, and the rotation contact seal 14 on the other side in the axial direction (upper side in FIG. 1) may be provided on the rotation shaft 7 side.

  A second refrigerant channel 4 is formed in the stator jacket 5. The second refrigerant flow path 4 is formed as a concave groove 4 a that opens to the outer peripheral surface that contacts the frame 2 of the stator jacket 5. In addition, the form of the 2nd refrigerant | coolant flow path 4 is not limited to groove shape, For example, it is good also as a through-hole formed in the inside of the stator jacket 5. FIG. The second refrigerant flow path 4 is spirally provided on the outer peripheral surface of the stator jacket 5. The groove portion 4a has a rectangular cross section in this example, but may have other cross sectional shapes such as a circular shape or an elliptical shape. A second refrigerant inlet / outlet 18 communicated with the second refrigerant flow path 4 is provided on the other axial side of the outer peripheral surface of the frame 2 (upper side in FIG. 1).

  The first refrigerant channel 9 is formed between the rotary shaft 7 and the fixed shaft 8. In the present embodiment, the first refrigerant flow path 9 is formed as a concave groove 9 a that opens on the inner peripheral surface of the rotating shaft 7. The first refrigerant flow path 9 may be formed as a concave groove that opens on the outer peripheral surface of the fixed shaft 8, or may be a flow hole formed inside the rotary shaft 7. The first refrigerant flow path 9 is spirally provided on the inner peripheral surface of the rotary shaft 7. The groove portion 9a has a rectangular cross section in this example, but may have other cross sectional shapes such as a circular shape or an elliptical shape. A first refrigerant inlet / outlet port 16 communicating with the first refrigerant flow path 9 is provided on the other axial side of the inner peripheral surface 8a of the fixed shaft 8 (upper side in FIG. 1).

  The anti-load side bracket 11 includes a communication channel 17 inside. The communication flow path 17 extends from the anti-load side bracket 11 into the fixed shaft 8 and extends into the frame 2, and connects the first refrigerant flow path 9 and the second refrigerant flow path 4.

  A refrigerant supply path such as a tube (not shown) connected to a refrigerant supply source (not shown) is connected to the first refrigerant inlet / outlet 16 of the fixed shaft 8 through the inside of the fixed shaft 8. The first refrigerant inlet / outlet 16 is supplied to the first refrigerant flow path 9. The refrigerant supplied to the first refrigerant flow path 9 spirally flows along the first refrigerant flow path 9 from the other side in the axial direction toward the one side in the axial direction, and the rotor 6 fixed to the rotary shaft 7. Cool down. The refrigerant that has cooled the rotor 6 flows from one axial direction side of the first refrigerant flow path 9 into the communication flow path 17 in the anti-load side bracket 11, and flows from the communication flow path 17 into the second refrigerant flow path 4. . The refrigerant that has flowed into the second refrigerant flow path 4 spirally flows along the second refrigerant flow path 4 from one axial direction side to the other axial direction side, thereby cooling the stator 3. The refrigerant that has cooled the stator 3 flows into the second refrigerant inlet / outlet 18 in the frame 2 from the other axial side of the second refrigerant flow path 4, and is discharged from the second refrigerant inlet / outlet 18 to the outside of the rotating electrical machine 1.

  In contrast to the above, the refrigerant may be supplied from the second refrigerant inlet / outlet 18, circulated from the second refrigerant channel 4 to the first refrigerant channel 9, and discharged from the first refrigerant inlet / outlet 16. The refrigerant used in the present embodiment may be a liquid such as cooling water or cooling oil, or may be a gas such as air.

<Effect of embodiment>
As described above, the rotating electrical machine 1 of the present embodiment has the first refrigerant flow path 9 formed between the rotating shaft 7 and the fixed shaft 8. By circulating the refrigerant through the first refrigerant flow path 9, the rotor 6 fixed to the rotary shaft 7 can be cooled. Thus, since the rotary electric machine 1 of this embodiment has a cooling structure about the rotor 6, cooling capacity can be improved.

  In the present embodiment, in particular, the rotating electrical machine 1 includes a stator jacket 5 that is disposed between the frame 2 and the stator 3 and in which the second refrigerant flow path 4 is formed. The stator 3 can be cooled by circulating the refrigerant through the second refrigerant flow path 4. Thus, since the rotary electric machine 1 of this embodiment has a cooling structure about both the stator 3 and the rotor 6, it can further improve a cooling capability.

  Further, particularly in the present embodiment, the rotating electrical machine 1 includes a non-load side bracket 11 disposed on one side in the axial direction of the frame 2. The anti-load side bracket 11 includes a communication channel 17 that communicates the first refrigerant channel 9 and the second refrigerant channel 4 inside. Thereby, since it becomes unnecessary to provide the refrigerant inlet / outlet for each of the first refrigerant flow path 9 and the second refrigerant flow path 4, the configuration can be simplified. In addition, since the refrigerant can be cooled also in the anti-load side bracket 11 by circulating the refrigerant through the communication flow path 17 of the anti-load side bracket 11, the cooling capacity of the rotating electrical machine 1 can be further increased.

  In the present embodiment, in particular, the fixed shaft 8 has a hollow structure. This makes it possible to dispose a tube for supplying or discharging the refrigerant to the first refrigerant flow path 9 in the fixed shaft 8, other electrical wiring, etc., so that the rotating electrical machine 1 can be made compact. Can do.

  In the present embodiment, in particular, the frame 2 has the second refrigerant inlet / outlet 18 communicated with the second refrigerant flow path 4 on the other axial side of the outer peripheral surface, and the fixed shaft 8 is in the axial direction of the inner peripheral surface. A first refrigerant inlet / outlet port 16 communicated with the first refrigerant flow path 9 is provided on the other side. Since both the first refrigerant inlet / outlet 16 and the second refrigerant inlet / outlet 18 are disposed on the other axial side of the fixed shaft 8 and the frame 2, the refrigerant can be circulated almost throughout the rotating shaft 7 and the frame 2. . Therefore, the cooling performance can be sufficiently exhibited.

  As described above, the rotating electrical machine 1 of the present embodiment is configured as a so-called direct drive type motor. In the rotary electric machine 1, the rotary shaft 7 is directly fixed to the rotary table 20, so that the heat of the stator 3 and the rotor 6 is easily conducted to the rotary table 20. For this reason, when the cooling capacity of the rotating electrical machine is low, there is a possibility that the rotating table 20 may be affected by heat (for example, the processing accuracy of the workpiece placed on the rotating table 20 may be reduced). Therefore, by applying the configuration according to the above embodiment to a direct drive type rotating electrical machine as in this embodiment, it is possible to reduce the influence of heat on the load object. That is, the direct drive type rotating electrical machine 1 is particularly suitable as an application target of the configuration according to the above embodiment.

  In this embodiment, in particular, the rotor 6 is a so-called SPM (Surface Permanent Magnet) type rotor in which a plurality of permanent magnets are installed on the outer peripheral surface of the rotating shaft 7. Thereby, the air cooling effect of a permanent magnet can be improved and the heat_generation | fever of the rotor 6 can be suppressed.

<Modification>
The disclosed embodiments are not limited to the above, and various modifications can be made without departing from the spirit and technical idea thereof. Hereinafter, such modifications will be described.

(1) When the refrigerant flow path is formed on the turntable In the above embodiment, the refrigerant flow path is not formed on the turntable 20, but the refrigerant flow path may also be formed in the turntable 20. An example of this modification is shown in FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  As shown in FIG. 2, in this modification, the turntable 20 includes a third refrigerant channel 21 inside. The third refrigerant flow path 21 is provided in an annular shape along the circumferential direction of the turntable 20. In addition, the form of the 3rd refrigerant | coolant flow path 21 is not limited to cyclic | annular form, For example, radial shape, spiral shape, etc. may be sufficient. Moreover, although the hole 21a of the 3rd refrigerant | coolant flow path 21 has a rectangular cross section in this example, it is good also as other cross-sectional shapes, such as circular shape and ellipse shape. On one side of the rotating shaft 8 (left side in FIG. 2), an inlet-side communication channel 22 that communicates the third refrigerant channel 21 and the first refrigerant inlet / outlet port 16 is provided in the axial direction. Further, on the other side (right side in FIG. 2) of the rotating shaft 8, an outlet side communication channel 23 that communicates the third refrigerant channel 21 and the first refrigerant channel 9 is provided. In the present modification, the first refrigerant inlet / outlet port 16 communicates with the first refrigerant channel 9 via the third refrigerant channel 21 and does not communicate directly with the first refrigerant channel 9.

  In this modification, the refrigerant from the refrigerant supply source is supplied from the first refrigerant inlet / outlet 16 to the third refrigerant channel 21 via the inlet-side communication channel 22 of the rotary shaft 7. The refrigerant supplied to the third refrigerant flow path 21 flows in the circumferential direction in the turntable 20 according to the third refrigerant flow path 21 and cools the turntable 20. The refrigerant that has cooled the turntable 20 flows into the first refrigerant flow path 9 via the outlet-side communication flow path 23 of the rotary shaft 7 and is supplied to the first refrigerant flow path 9. Thereafter, as in the above embodiment, the refrigerant flows through the first refrigerant flow path 9 to cool the rotor 6, and then supplied to the second refrigerant flow path 4 via the communication flow path 17 of the anti-load side bracket 11. The stator 3 is cooled by flowing through the second refrigerant flow path 4.

  As described above, in the present modification, the rotary table 20 that is the load object includes the third refrigerant channel 21 that communicates with the first refrigerant channel 9 inside. Thereby, it is possible to cool the rotary table 20 by circulating the refrigerant through the third refrigerant flow path 21, and the influence of heat on the rotary table 20 can be further reduced.

(2) When the refrigerant flow path is provided along the axial direction In the above embodiment, the case where the first refrigerant flow path 9 is spirally formed between the rotating shaft 7 and the fixed shaft 8 has been described as an example. For example, the first refrigerant flow path may be formed along the axial direction. An example of this modification is shown in FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  As shown in FIG. 3, in the present modification, the first refrigerant flow path 25 along the axial direction is provided between the rotating shaft 7 and the fixed shaft 8 at a plurality of locations in the circumferential direction (eight locations in this example). ing. The first refrigerant channel 25 is formed as a concave groove that opens on the inner peripheral surface of the rotary shaft 7. The first coolant channel 25 may be formed as a concave groove opening on the outer peripheral surface of the fixed shaft 8, or may be a flow hole formed inside the rotary shaft 7. A plurality of first refrigerant inlets / outlets 26 communicating with each of the plurality of first refrigerant flow paths 25 are provided on the other axial side of the fixed shaft 8 (upper side in FIG. 3). On the lower side in FIG. 3, one annular outlet-side communication channel 27 that communicates with the plurality of first refrigerant channels 25 is provided. The outlet side communication channel 27 communicates with the communication channel 17 in the anti-load side bracket 11.

  In this modification, the refrigerant from the refrigerant supply source is supplied to each first refrigerant flow path 25 from each first refrigerant inlet / outlet 26. The refrigerant supplied to each first refrigerant flow path 25 flows from the other axial side toward the one axial side according to each first refrigerant flow path 25 to cool the rotor 6. The refrigerant that has cooled the rotor 6 flows into the outlet-side communication flow path 27 on one axial side of each first refrigerant flow path 25, and merges in the outlet-side communication flow path 27 to be in the anti-load side bracket 11. It flows into the communication channel 17. Thereafter, as in the above embodiment, the refrigerant is supplied to the second refrigerant flow path 4 through the communication flow path 17 and flows through the second refrigerant flow path 4 to cool the stator 3.

  Even in this modification, the same effects as those of the above embodiment are obtained. In the above description, the second refrigerant flow path 4 is formed in a spiral shape. However, the present invention is not limited to this, and the second refrigerant flow path 4 is provided along the axial direction in the same manner as the first refrigerant flow path 25. May be.

(3) Others Although the fixed shaft 8 has a hollow structure in the above, it is not limited to this and may have a solid structure.

  Moreover, although the case where the rotary electric machine 1 was a motor was demonstrated as an example above, this embodiment is applicable also when the rotary electric machine 1 is a generator.

  In addition to those already described above, the methods according to the above-described embodiments and modifications may be used in appropriate combination.

  In addition, although not illustrated one by one, the above-mentioned embodiment and each modification are implemented with various modifications within a range not departing from the gist thereof.

DESCRIPTION OF SYMBOLS 1 Rotating electrical machine 2 Frame 3 Stator 4 Second refrigerant flow path 5 Stator jacket 6 Rotor 6a Permanent magnet 7 Rotating shaft 8 Fixed shaft 9 First refrigerant flow path 11 Anti-load side bracket (bracket)
13 Bearing 16 First refrigerant inlet / outlet 17 Communication flow path 18 Second refrigerant inlet / outlet 20 Rotary table (object to be loaded)
21 Third refrigerant channel 25 First refrigerant channel 26 First refrigerant inlet / outlet

Claims (8)

A hollow rotating shaft having a rotor fixed and rotatably supported by a bearing;
A fixed shaft inserted inside the rotating shaft;
A rotating electrical machine comprising: a first coolant channel formed between the rotating shaft and the fixed shaft. Frame,
A stator fixed to the inside of the frame and opposed to the rotor via a gap in the radial direction;
2. The rotating electrical machine according to claim 1, further comprising a stator jacket disposed between the frame and the stator and having a second refrigerant flow path formed therein. 3. The bracket according to claim 2, further comprising a bracket that is disposed on one side in the axial direction of the frame and includes a communication channel that communicates the first refrigerant channel with the second refrigerant channel. 4. Rotating electric machine. The fixed shaft is
The rotating electrical machine according to claim 3, wherein the rotating electrical machine has a hollow structure. The fixed shaft is
A first refrigerant inlet / outlet communicated with the first refrigerant flow path on the other axial side of the inner peripheral surface;
The frame is
5. The rotating electrical machine according to claim 4, further comprising a second refrigerant inlet / outlet communicating with the second refrigerant channel on the other axial side of the outer peripheral surface. The rotating shaft is
The rotating electrical machine according to any one of claims 1 to 5, wherein the rotating electrical machine is directly fixed to a load object. The load object is
The rotating electrical machine according to claim 6, further comprising a third coolant channel communicating with the first coolant channel. The rotor is
The rotating electrical machine according to any one of claims 1 to 7, further comprising a plurality of permanent magnets installed on an outer peripheral surface of the rotating shaft.

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