JP2016119764A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve good heat radiation performance by using a heat radiation member sandwiched between a motor case and a stator coil in a rotary electric machine.SOLUTION: A rotary electric machine 10 includes: a stator 12 including a stator core 20 and a coil wound around the stator core 20; a rotor 14 disposed at the inner periphery side of the stator 12 and having a rotor rotary shaft 32; a motor case 16 which fixes the outer periphery side of the stator core 20 and rotatably supports the rotor rotary shaft 32; and a heat radiation member 40 sandwiched between an outer peripheral surface of a coil end 22 protruding in an axial direction of the stator core 20 and an inner wall surface 18 of the motor case 16. The heat radiation member 40 includes: an outer resin member 42 made of a material having high heat insulation quality and high oil resistance; and an inner resin member 44 made of a material having high heat conductivity and high elasticity. An entire outer peripheral surface of the inner resin member 44 is covered by the outer resin member 42.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotating electrical machine having a heat dissipation structure for a stator coil.

  Since the coil wound around the stator of the rotating electrical machine generates heat by operation, its heat dissipation structure is necessary.

  In Patent Document 1, as a motor, a heat transfer plate is arranged at a position facing the outer periphery of the coil end and the inner peripheral surface of the frame inside the motor frame, and the coil end side is disposed between the heat transfer plate and the outer periphery of the coil end. Providing a heat conductive sheet made of a laminated resin of a low hardness silicone resin and a high hardness silicone resin on the heat transfer plate side is disclosed.

  Patent Document 2 discloses a configuration in which an opening window is provided in a front bracket attached to a stator case as a brushless motor, and a stator coil is disposed so as to face the opening window. An example of occlusion is described. As the heat conductive member, a resin having high heat conductivity and stretchability is filled in a gel at a high temperature to fill the opening window, and then cured.

JP 2013-126292 A JP 2008-259383 A

  Patent Document 1 discloses that a heat dissipation member is provided between a motor case and a stator coil. Patent Document 1 uses a combination of low and high hardness silicone resin so as not to create a gap between the motor case and the stator coil. In No. 2, a thermosetting resin is used which is filled in a gap in a gelled state and then cured. As a cooling medium for a rotating electrical machine, oil is often used in addition to air and water. Considering these, the heat dissipating member provided between the stator coil and the motor case is required to have high electrical insulation, oil resistance, thermal conductivity, stretchability, and the like.

  Silicone resins have high stretchability, thermal conductivity, and electrical insulation, but are not oil resistant and may be deteriorated when cooling oil is used. A thermosetting resin has high thermal conductivity, oil resistance, and electrical insulation, but has poor stretchability. For example, it cannot absorb the difference in thermal expansion between the motor case and the stator coil during operation. As described above, there is currently no material that satisfies all the characteristics required for the heat dissipation member sandwiched between the motor case and the stator coil.

  The objective of this invention is providing the rotary electric machine provided with the member for thermal radiation which is pinched | interposed between a motor case and a stator coil and exhibits favorable heat dissipation.

  A rotating electrical machine according to the present invention includes a stator including a stator core and a coil wound around the stator core, a rotor having a rotor rotating shaft disposed on the inner peripheral side of the stator, and rotating the rotor rotating shaft while fixing the outer peripheral side of the stator core. A motor case that is freely supported, and a heat radiating member that is sandwiched between the outer peripheral surface of the coil end that protrudes in the axial direction of the stator core and the inner wall surface of the motor case. Including an outer resin member made of a material having a high oil resistance and an inner resin member made of a material having a high thermal conductivity and a high stretchability. Features.

  In the rotating electrical machine according to the present invention, the outer resin member is preferably a resin member based on fluorine or polyimide, and the inner resin member is preferably a silicone resin.

  In the rotating electrical machine according to the present invention, the heat radiating member is preferably sandwiched between the inner wall surface of the cover portion that supports the rotor rotation shaft of the motor case and the outer peripheral surface of the coil end facing the cover.

  In the rotating electrical machine according to the present invention, it is preferable that the heat dissipating member is sandwiched between the entire circumference along the circumferential direction of the inner wall surface of the motor case and the outer circumferential surface of the coil end facing this.

  In the rotating electrical machine according to the present invention, it is preferable that the heat dissipating member is disposed on the side opposite to the lead side on which the lead lead of the coil at the coil end is disposed.

  The rotating electrical machine according to the present invention, as a heat dissipation member sandwiched between the outer peripheral surface of the coil end and the inner wall surface of the motor case, an outer resin member made of a material having high electrical insulation and high oil resistance; An inner resin member made of a material having high thermal conductivity and high stretchability, and the entire outer peripheral surface of the inner resin member is covered with the outer resin member. Since this heat radiating member has high characteristics such as electrical insulation, oil resistance, thermal conductivity, and stretchability, it can be sandwiched between the motor case and the stator coil to exhibit good heat dissipation.

  In the rotating electrical machine according to the present invention, the outer resin member is a resin member based on fluorine or polyimide, and the inner resin member is a silicone resin. Any of oil resistance, thermal conductivity, and stretchability can have high characteristics.

  In the rotating electrical machine according to the present invention, the heat dissipating member is sandwiched between the inner wall surface of the cover portion that supports the rotor rotating shaft of the motor case and the outer peripheral surface of the coil end facing the cover. Since the heat dissipating member is sandwiched between the axial ends of the rotating electrical machine, the stator can be easily attached and detached as compared with the case where it is fixed by adhesion or thermosetting resin.

  In the rotating electrical machine according to the present invention, the heat radiating member is sandwiched between the entire circumference along the circumferential direction of the inner wall surface of the motor case and the outer circumferential surface of the coil end facing the same. Thereby, heat dissipation improves compared with the case where it arranges partially.

  In the rotating electrical machine according to the present invention, the heat dissipating member is disposed on the opposite lead side that is opposite to the lead side of the coil end. The lead side has a complicated structure such as bonding between coils, bonding between a coil and a lead, bonding between a lead and external wiring, or the like. Compared to this, a heat radiating member can be easily arranged on the non-lead side. Therefore, the heat dissipation member can be exhibited by sandwiching the heat dissipation member by a simple operation or the like.

It is sectional drawing of the rotary electric machine of embodiment which concerns on this invention. FIG. 2 is a detailed view of a part A in FIG. 1.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In the following, a rotating electrical machine mounted on a vehicle will be described, but this is an illustrative example, and a rotating electrical machine for other purposes may be used. The materials and the like described below are examples for explanation, and can be appropriately changed according to the specifications of the rotating electrical machine. Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view of the rotating electrical machine 10. The rotating electrical machine 10 is a three-phase synchronous motor / generator mounted on a vehicle. The rotating electrical machine 10 includes a stator 12, a rotor 14, a motor case 16, an outer peripheral surface of a coil end 22 that protrudes from a stator axial end of a coil wound around the stator 12, and an inner wall surface of the motor case 16. It is configured to include a heat dissipation member 40 sandwiched therebetween.

  The stator 12 includes an annular stator core 20 and a coil wound around the stator core 20. The stator core 20 is an annular magnetic part formed by laminating a plurality of laminated steel plates formed in a predetermined shape. Instead of the laminated steel sheet, a magnetic powder integrally formed may be used. In FIG. 1, the coil ends 22 and 24 are shown as the coils wound around the stator core 20 at portions protruding from both end portions in the axial direction of the stator core 20. FIG. 1 shows an axial direction, a radial direction, and a circumferential direction in the rotating electrical machine 10.

  One of the coil ends 22, 24 has a lead drawn from the coil. When distinguishing the two coil ends 22 and 24 below, the one disposed on one side of both axial end faces of the stator core 20 is referred to as the coil end 22 on the opposite lead side, and the other is disposed on the other side. Is called the coil end 24 on the lead side.

  The rotor 14 includes a rotor core 30 and a rotor rotation shaft 32. The rotor core 30 is an annular magnetic part formed by laminating a plurality of laminated steel plates formed in a predetermined shape. Instead of the laminated steel sheet, a magnetic powder integrally formed may be used. The magnetic poles of the rotor 14 are formed by a plurality of permanent magnets arranged in a predetermined arrangement on the outer peripheral side of the rotor core 30, but the illustration of the permanent magnets is omitted in FIG. The permanent magnet generates torque in cooperation with a rotating magnetic field generated by applying a predetermined energization to the coil wound around the stator 12, thereby rotating the rotor rotating shaft 32.

  The motor case 16 fixes the outer peripheral side of the stator core 20 and rotatably supports the rotor rotating shaft 32 with a bearing 34, and houses the stator 12 and the rotor 14 in the case internal space. Cooling oil circulates inside the motor case 16 to cool the coils of the stator 12 that generate heat by the operation of the rotating electrical machine 10. As the motor case 16, a metal material having an appropriate strength, heat resistance, and oil resistance formed into a predetermined shape is used. An iron material such as cast iron is used as the metal material.

  The heat radiating member 40 is a member for radiating the coil of the stator 12 that generates heat when the rotary electric machine 10 operates to the metal motor case 16 side. The heat dissipating member 40 is sandwiched between the inner wall surface of the cover portion that supports the rotor rotating shaft 32 in the motor case 16 and the outer peripheral surface of the coil end facing the cover. In the example of FIG. 1, a heat radiating member is provided between the entire circumference along the circumferential direction of the inner wall surface 18 of the cover portion that supports the rotor rotation shaft 32 of the motor case 16 and the outer circumferential surface of the coil end 22 facing this. 40 is clamped. The heat dissipating member 40 has an annular shape as a whole, and one outer peripheral surface of the annular axial direction faces the inner wall surface 18 of the motor case 16 and the other outer peripheral surface of the coil end 22 on the opposite lead side. Facing the outer surface.

  The pinching means that the annular heat radiating member 40 is sandwiched and held between the inner wall surface 18 of the motor case 16 and the coil end 22 rather than being fixed by bonding or the like. Since the motor case 16 and the stator 12 are not fixed by bonding or the like, the stator 12 can be easily attached and detached in the rotating electrical machine 10.

  The heat radiation member 40 includes an outer resin member 42 and an inner resin member 44, and the entire outer peripheral surface of the inner resin member 44 is covered with the outer resin member 42. FIG. 2 is an enlarged view of a portion A in FIG. That the entire outer peripheral surface of the inner resin member 44 is covered with the outer resin member 42 means that the outer peripheral surface of the inner resin member 44 is completely covered with the outer resin member 42 and the inner resin member 44 is not exposed. For example, the outer resin member 42 can have a hollow portion, and the inner resin member 44 can be enclosed in the hollow portion. Or you may take the structure which coats the outer peripheral surface of the inner side resin member 44 by the outer side resin member 42 of sufficient thickness which the outer peripheral surface of the inner side resin member 44 does not expose. As long as the inner resin member 44 is completely covered, the outer resin member 42 is preferably as thin as possible.

  The outer resin member 42 is made of a material having high electrical insulation and high oil resistance. As a result, the inner resin member 44 is protected from the cooling oil, and the motor case 16 and the coil end 22 are electrically insulated. Thereby, the shape change, characteristic deterioration, and embrittlement of the heat radiating member 40 in an oil-in-water environment can be prevented, and the generation of foreign matters and the like can be suppressed. As the outer resin member 42, a resin member based on fluorine or polyimide can be used.

  The inner resin member 44 is a portion that becomes a core of the heat radiation member 40 and is made of a material having high thermal conductivity and high stretchability. As a result, the heat of the coil end 22 can be conducted to the metal motor case 16 side and radiated to the outside air side, and the stator 12 including the coil end 22 can be cooled. Further, by absorbing the dimensional variation of the motor case 16 and the outer shape variation of the coil end 22, the gap that can be generated between the inner wall surface 18 of the motor case 16 and the outer peripheral surface of the coil end 22 can be reduced. Moreover, since it acts as a cushioning material when the stator 12 is assembled to the motor case 16, it is possible to reduce the load received by the coil during the assembly. Further, the difference between the thermal expansion of the motor case 16 due to the ambient temperature during operation of the rotating electrical machine 10 and the thermal expansion of the stator 12 including the coil end 22 is absorbed, and the coil is damaged due to the thermal expansion difference during operation. Can be suppressed. As the inner resin member 44, a silicone resin can be used.

  In the above description, the heat radiating member 40 is sandwiched between the anti-lead side coil end 22 and the motor case 16, but may be further sandwiched between the lead side coil end 24 and the motor case 16. . Moreover, although the heat radiating member 40 has an annular shape and is sandwiched between the motor case 16 and the coil end 22 over the entire circumference along the circumferential direction, it is effective even if it does not extend over the entire circumference. It is also possible to hold it only in places where heat can be dissipated.

  According to the above configuration, the rotating electrical machine 10 exhibits the following effects. Since the heat radiating member 40 has elasticity, it can be clamped between the coil and the motor case, and can be assembled without damaging the coil. Since the assembly can be performed in close contact with the coil and the motor case without gaps, the thermal conductivity between the coil and the motor case is improved. Since it has stretchability, it is not easily affected by the difference in thermal expansion of the material in heat dissipation performance. Since adhesion is not required, the stator can be detached. Since the heat radiating member 40 does not need to be molded, the assembly of the stator and the like is easy and inexpensive. Moreover, electrical insulation and oil resistance can be ensured mainly by the characteristics of the outer resin member 42 of the heat radiating member 40. Thereby, combined use with the oil cooling of a coil is attained, coil cooling performance improves, and the temporal deterioration of the heat radiating member 40 can be suppressed. Further, high thermal conductivity can be realized mainly by the characteristics of the inner resin member 44 of the heat radiating member 40, the cooling performance of the coil is improved, and the operating range of the rotating electrical machine 10 is expanded.

  DESCRIPTION OF SYMBOLS 10 Rotating electrical machine, 12 Stator, 14 Rotor, 16 Motor case, 18 Inner wall surface, 20 Stator core, 22, 24 Coil end, 30 Rotor core, 32 Rotor rotating shaft, 34 Bearing, 40 Heat radiation member, 42 Outer resin member, 44 Inside Resin member.

Claims (5)

A stator including a stator core and a coil wound around the stator core;
A rotor disposed on the inner peripheral side of the stator and having a rotor rotation axis;
A motor case that fixes the outer peripheral side of the stator core and rotatably supports the rotor rotation shaft;
A heat dissipating member sandwiched between the outer peripheral surface of the coil end protruding in the axial direction of the stator core and the inner wall surface of the motor case;
With
The heat dissipation member is
An outer resin member made of a material having high electrical insulation and high oil resistance;
The entire outer peripheral surface is covered with an outer resin member, and an inner resin member made of a material having high thermal conductivity and high stretchability;
A rotating electrical machine. In the rotating electrical machine according to claim 1,
The outer resin member is a resin member based on fluorine or polyimide,
The rotating electrical machine wherein the inner resin member is a silicone resin. In the rotating electrical machine according to claim 1,
The heat dissipation member is
A rotating electrical machine characterized by being sandwiched between an inner wall surface of a cover portion that supports a rotor rotating shaft of a motor case and an outer peripheral surface of a coil end facing the same. In the rotating electrical machine according to claim 3,
The heat dissipation member is
A rotating electrical machine characterized by being sandwiched between the entire circumference along the circumferential direction of the inner wall surface of a motor case and the outer circumferential surface of a coil end facing the circumference. In the rotating electrical machine according to claim 3,
The heat dissipation member is
A rotating electrical machine, characterized in that the rotating electrical machine is disposed on a side opposite to a lead side on which a lead lead of a coil at a coil end is disposed.

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