JP2004112967A - Cooling structure for rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling structure for rotary electric machine excellent in cooling performance. <P>SOLUTION: In a rotary electric machine, a rotor 30 coupled with a rotating shaft and a stator 20 arranged coaxially outside the rotor 30 are housed in a case 10 and for the stator 20, a plurality of stator cores 21 extended axially are arranged in circumferential direction, and a coil 22 is wound on the stator core 21. The electric machine is equipped with a first refrigerant passage 50 which is formed to pierce the stator core 21 through in axial direction, and a second refrigerant passage 24 which is formed between adjacent stator cores. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotating electric machine cooling structure that efficiently cools a stator of a rotating electric machine (such as a motor, a generator, and a motor / generator).
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a rotating electric machine (for example, a motor, a generator or a motor / generator), a stator core is formed by making a through hole in a stator core, passing a hollow bolt through the through hole, and flowing a refrigerant through the hollow bolt. A cooling method is disclosed (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP 10-336966 A
[Problems to be solved by the invention]
However, in the above-described conventional technology, since the distance between the stator coil, which is a heat source, and the refrigerant is large, the performance of cooling the stator coil is not so good because of the influence of the stator core and the hollow bolt.
[0005]
The present invention has been made in view of such conventional problems, and has as its object to provide a cooling structure of a rotating electric machine having excellent cooling performance.
[0006]
[Means for Solving the Problems]
The present invention solves the above problem by the following means. Note that, for easy understanding, reference numerals corresponding to the embodiments of the present invention are given, but the present invention is not limited thereto.
[0007]
According to the present invention, a rotor (30) connected to a rotating shaft and a stator (20) arranged coaxially outside the rotor (30) are housed in a case (10), and the stator (20) is In a rotating electrical machine in which a plurality of stator cores (21) extending in the axial direction are arranged in the circumferential direction and a coil (22) is wound around the stator core (21), the stator core (21) is axially penetrated. It is characterized by comprising a first refrigerant passage (50) formed and a second refrigerant passage (24) formed between adjacent stator cores.
[0008]
[Action / Effect]
According to the present invention, since the coil and the stator core can be cooled by the refrigerant flowing through the first and second refrigerant passages, excellent cooling performance is exhibited.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings and the like.
(1st Embodiment)
1 and 2 are cross-sectional views illustrating a rotating electric machine according to a first embodiment of the present invention. Note that FIG. 1 is a view taken along the line II of FIG. 2, and FIG. 2 is a view taken along the line II-II of FIG.
The rotating electric machine 1 includes a case 10, a stator 20, and a rotor 30, and functions as, for example, a motor, a generator, or a motor / generator.
[0010]
The case 10 includes a cylindrical portion 11 and side plate portions 12 and 13 for closing openings at both axial ends of the cylindrical portion 11. The side plates 12, 13 are fixed to the cylindrical portion 11 by bolts or the like (not shown). The side plates 12, 13 are provided with bearings 12d, 13d for rotatably supporting a rotation shaft 32 (described later) of the rotor 30. A cooling water channel 12 a is formed inside the side plate portion 12, and a cooling water channel 13 a is formed inside the side plate portion 13. Further, a water supply port 12b is formed in the cooling water channel 12a, and a drain port 13b is formed in the cooling water channel 13a. The cooling water supplied from the outside is taken in from a water supply port 12b, passes through a cooling water flow path 12a, a water flow pipe 50 (described later), and a cooling water flow path 13a, and is discharged from a drain port 13b. The water supply port 12b has a size corresponding to a device for supplying cooling water.
[0011]
An oil inlet 12c is formed in the side plate portion 12, and an oil outlet 13c is formed in the side plate portion 13.
[0012]
Stator 20 is provided on the inner periphery of cylindrical portion 11 of case 10. The stator 20 has a stator core 21 and a stator coil 22 (see FIG. 3). On the rotor side surface (inner peripheral surface) of the stator, cylindrical inner peripheral wall surfaces 23a and 23b are formed, and one end of the inner peripheral wall surfaces 23a and 23b is fixed to the side plate portions 12 and 13. Have been. Heat conduction rings 41 and 42 capable of conducting heat are provided between the stator core 21 and the side plates 12 and 13 and along the inner peripheral surface of the cylindrical portion 11 of the case 10. . The first cooling oil chamber 24a is defined by the stator inner peripheral wall surface 23a, the stator core 21, the side plate portion 12, and the heat conduction ring 41. Further, a second cooling oil chamber 24b is defined by the stator inner peripheral wall surface 23b, the stator core 21, the side plate portion 13, and the heat conduction ring 42.
[0013]
The stator core 21 has a back core 21a inscribed in the cylindrical portion 11 of the case 10, and teeth 21b extending from the back core 21a to the inner peripheral side (see FIG. 3).
[0014]
Further, the stator 20 is provided with a water pipe 50 penetrating through the stator core 21 and the heat conduction rings 41 and 42. One end of the water pipe 50 is connected to the cooling water passage 12a, and the other end is connected to the cooling water passage 13a, so that the cooling water can flow through the cooling water passages 12a to 13a.
[0015]
The oil taken in from the oil inlet 12c absorbs the heat of the stator coil 22 until it passes through the first cooling oil chamber 24a and the second cooling oil chamber 24b and is discharged from the oil discharge port 13c. The heat is transmitted to the water pipe 50 via the heat transfer rings 41 and 42 and is cooled by the cooling water flowing through the water pipe 50.
[0016]
With such a structure, the cooling performance for cooling the stator coil 22 varies depending on the material, dimensions (size) of the heat conduction rings 41 and 42, and the like. For example, in a case where the temperature of the stator coil 22 is not increased (for example, the heat exchange between the cooling water and the cooling oil is actively performed), as in a case where the heat generation amount of the coil is larger than that of the stator core and there is a concern about an increase in the oil temperature. In this case, a material having a high thermal conductivity (for example, aluminum) may be used as the material of the heat conduction rings 41 and 42. Further, the thickness of the heat conduction rings 41 and 42 may be reduced.
[0017]
On the other hand, when heat exchange between the cooling water and the cooling oil is not desired to be large, such as when the heat generated by the stator core is larger than that of the coil and there is a concern that the water temperature may rise, the material of the heat conduction rings 41 and 42 may be used. It is preferable to use a material having low thermal conductivity (for example, stainless steel). Further, it is preferable to increase the thickness of the heat conduction rings 41 and 42.
[0018]
The heat conduction rings 41 and 42 of the present embodiment have uneven heat absorbing fins 41 a and 42 a on the inner periphery of the cylindrical portion 11 and in the vicinity of the side plates 12 and 13. The heat absorbing fins 41a and 42a are arranged in the first cooling oil chamber 24a and the second cooling oil chamber 24b, and absorb heat from the cooling oil flowing through the first cooling oil chamber 24a and the second cooling oil chamber 24b.
[0019]
The rotor 30 is arranged inside the stator 20. The rotor 30 includes a columnar rotor core 31 and a rotation shaft 32 that is disposed on the center axis of the rotor core 31. Both ends of the rotating shaft 32 are supported by the side plates 12, 13 via bearings 12d, 13d, respectively, and are rotatable. A magnet 31a is arranged near the outer peripheral surface of the rotor 30.
[0020]
Next, the stator 20 will be described in more detail with reference to FIG. 3 (a view taken along the line III-III in FIG. 1).
[0021]
The stator core 21 of the stator 20 includes a ring-shaped back core 21a along the cylindrical portion 11, and teeth 21b projecting radially inward from the back core 21a. An insulating cap 21d is attached to the teeth 21b, and a stator coil 22 is wound around the cap 21d. The insulating cap 21d has insulating performance and prevents conduction between the stator core 21 and the stator coil 22. The surface of the insulating cap 21d is the end face of the stator 20 (see FIG. 1).
[0022]
The stator 20 is press-fitted (shrink-fit or the like) into the cylindrical portion 11 of the case 10, so that the stator 20 is fixed to the case 10.
[0023]
The space between the teeth 21b is a slot 21c, and the stator coil 22 is passed through the slot 21c. The slot 21c is a groove-shaped space that is open at both ends in the axial direction and at the radially inner peripheral side, and is used to cool the stator coil 22 by closing the radially inner peripheral opening with the resin 21e. The slot 21c is used as the oil passage 24 through which the cooling oil can flow. The oil passage 24 thus formed communicates with the first cooling oil chamber 24a and the second cooling oil chamber 24b. Therefore, as described above, the oil taken in from the oil inlet 12c passes through the first cooling oil chamber 24a, the oil passage 24, and the second cooling oil chamber 24b, and is discharged from the oil outlet 13c. During that time, the heat of the stator coil 22 is absorbed.
[0024]
Further, by using different refrigerants, a high-temperature refrigerant can be cooled by a low-temperature refrigerant due to a difference in temperature between the refrigerants.
[0025]
According to the present embodiment, the cooling oil is caused to flow through the oil passage 24 to directly cool the stator coil 22 without generating rust, while maintaining the insulation properties, so that the cooling performance is excellent.
[0026]
Further, by providing the heat absorbing fins 41a and 42a, the performance of cooling the cooling oil flowing through the oil passage 24 can be further improved.
[0027]
The cooling performance can be adjusted optimally by appropriately selecting the material, size and the like of the heat conduction rings 41 and 42.
[0028]
(2nd Embodiment)
4 and 5 are cross-sectional views illustrating a rotating electric machine according to a second embodiment of the present invention. 4 is a view taken along the line IV-IV of FIG. 5, and FIG. 5 is a view taken along the line VV of FIG.
In addition, the portions that perform the same functions as those in the first embodiment described above are denoted by the same reference numerals, and redundant description will be omitted as appropriate.
[0029]
In the first embodiment, the case where the insulating cap 21d and the heat conduction rings 41 and 42 are formed separately has been described as an example, but in the present embodiment, both are integrally formed. That is, the end portions 41 b and 42 b of the heat conduction rings 41 and 42 serve as the insulating cap in the first embodiment, and prevent conduction between the stator core 21 and the stator coil 22.
[0030]
Further, the heat conduction rings 41 and 42 of the present embodiment are thicker than those of the first embodiment. In this embodiment, no heat absorbing fin is provided. As described above, when it is not desired to perform heat exchange between the cooling water and the cooling oil, it is preferable to increase the thickness of the heat conduction rings 41 and 42 and not to provide heat absorbing fins.
[0031]
According to the present embodiment, the end portions 41b and 42b of the heat conduction rings 41 and 42 prevent conduction between the stator core 21 and the stator coil 22, so that the number of components can be reduced and the cost can be reduced. Can be.
[0032]
In addition, without being limited to the embodiment described above, various modifications and changes are possible within the scope of the technical idea, and it is apparent that they are equivalent to the present invention.
[0033]
For example, when the insulating cap 21d and the heat conduction rings 41 and 42 are formed separately as in the first embodiment, the heat absorbing fins 41a and 42a may not be formed.
[0034]
Further, when the insulating cap 21d and the heat conducting rings 41 and 42 are integrally formed as in the second embodiment, heat absorbing fins 41a and 42a may be further formed.
[0035]
Furthermore, in this embodiment, the case where two different types of refrigerants are used has been described, but the same refrigerant may be used.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a rotating electric machine according to a first embodiment of the present invention as viewed from a direction perpendicular to an axis.
FIG. 2 is a cross-sectional view of the rotating electric machine according to the first embodiment of the present invention as viewed from an axial direction.
FIG. 3 is a view taken in the direction of arrows III-III in FIG. 1;
FIG. 4 is a cross-sectional view of a rotating electric machine according to a second embodiment of the present invention as viewed from a direction perpendicular to an axis.
FIG. 5 is a cross-sectional view of a rotating electric machine according to a second embodiment of the present invention as viewed from an axial direction.
[Explanation of symbols]
Reference Signs List 1 rotating electric machine 10 case 20 stator 21 stator core 21b teeth 21c slot 21e resin (slot closing member)
24 oil passage (second refrigerant passage)
30 rotor 41, 42 heat conduction ring (heat conduction member)
41a, 42a Heat absorbing fin (heat absorbing part)
50 Water pipe (first refrigerant passage)

Claims (9)

A rotor connected to a rotating shaft and a stator arranged coaxially outside the rotor are housed inside a case, and the stator includes a plurality of stator cores extending in an axial direction arranged in a circumferential direction. In a rotating electric machine with a coil wound around
A first refrigerant passage formed through the stator core in the axial direction;
A second refrigerant passage formed between adjacent stator cores,
A cooling structure for a rotating electric machine, comprising: 2. The cooling structure for a rotating electric machine according to claim 1, wherein cooling water flows as a refrigerant through the first refrigerant passage, and cooling oil flows through the second refrigerant passage as a refrigerant. 3. 3. The rotation according to claim 1, wherein the second refrigerant passage is formed by a slot closing member disposed near a tip of the tooth and closing an opening of a slot between the teeth. 4. Electric motor cooling structure. The said 1st refrigerant passage is connectable with the refrigerant | coolant supply apparatus which supplies a refrigerant | coolant, and has a connection port according to the refrigerant | coolant supply apparatus, The Claim 1 characterized by the above-mentioned. A cooling structure for a rotating electric machine according to the item. The heat of the refrigerant flowing through the second refrigerant passage is passed through the first refrigerant passage, and the heat of the refrigerant flowing through the first refrigerant passage and the refrigerant flowing through the second refrigerant passage are transmitted. The cooling structure for a rotating electric machine according to any one of claims 1 to 4, further comprising a heat conducting member for performing replacement. The heat conduction member is made of a material having a high heat conductivity, thereby increasing the heat exchange performance of the refrigerant flowing through the first and second refrigerant passages, and being made of a material having a low heat conductivity, The cooling structure for a rotating electric machine according to claim 5, wherein the heat exchange performance of the refrigerant flowing through the first and second refrigerant passages is reduced. The heat conducting member increases the heat exchange performance of the refrigerant flowing through the first and second refrigerant passages by reducing the thickness, and increases the thickness of the first and second refrigerants. The cooling structure for a rotating electric machine according to claim 5 or 6, wherein the heat exchange performance of the refrigerant flowing through the refrigerant passage is reduced. The rotation according to any one of claims 5 to 7, wherein the heat conduction member has a concave-convex heat absorbing portion capable of absorbing the heat of the refrigerant flowing through the second refrigerant passage. Electric motor cooling structure. An insulating member is provided between the teeth and the coil, and insulates the teeth and the coil,
The cooling structure for a rotating electric machine according to any one of claims 5 to 8, wherein the heat conductive member is formed integrally with the insulating member.

Images