Stator

Abstract

To provide a stator capable of improving cooling efficiency of a coil.SOLUTION: A stator 4 includes teeth 44 and coil members 42. The coil member 42 is attached to the teeth 44. The coil member 42 includes coils 45 and molds 46. The coil 45 spirally extends so as to be wound around the teeth 44. The mold 46 wraps the coil 45 so as to be in direct contact with the coil 45. The mold 46 includes a cooling channel 460. The mold 46 is made of diamond.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a stator. [Background technology]

[0002] A stator including teeth and coils wound around the teeth is known (see, for example, Patent Document 1). Such a stator includes a resin that encases the coil and includes a cooling passage. The coil is cooled by a coolant that flows through the cooling passage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-41770 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned stator, there is a need to improve the cooling efficiency of the coil. However, because the thermal conductivity of the resin is relatively low, there is a limit to the cooling of the coil by the refrigerant flowing through the cooling passage formed in the resin.

[0005] An object of the present invention is to provide a stator capable of improving the cooling efficiency of a coil. [Means for solving the problem]

[0006] The stator of the present invention comprises teeth and coil members attached to the teeth, the coil members having a coil extending in a spiral manner so as to be wound around the teeth, and a mold which encases the coil so as to be in direct contact with the coil and includes a cooling passage, the mold being constructed from diamond.

[0007] In this stator, the coil member has a mold that wraps the coil so as to be in direct contact with the coil and includes a cooling passage. This allows the coil to be cooled by the refrigerant flowing through the cooling passage. Moreover, the mold is made of diamond. Since diamond has electrical insulation properties, an aqueous refrigerant can be used as the refrigerant flowing through the cooling passage. Therefore, the cooling efficiency of the coil can be improved compared to, for example, a case where an oil-based refrigerant is used. In addition, since the thermal conductivity of diamond is relatively large, the cooling efficiency of the coil can be improved compared to, for example, a case where the mold contains a resin. Therefore, with this stator, the cooling efficiency of the coil can be improved.

[0008] The coil may be a rectangular coil, which makes it possible to easily manufacture the coil member by a three-dimensional modeling method.

[0009] A gap may exist between the teeth and the coil member, which allows the coil member to be properly attached to the teeth.

[0010] The cooling passage may include an outer region located outside the coil, thereby conserving volume for the cooling passage.

[0011] The cooling passage may include an inner region located inside the coil, thereby allowing efficient cooling of the coil from inside the coil. Effect of the Invention

[0012] According to the present invention, it is possible to provide a stator that can improve the cooling efficiency of a coil. [Brief description of the drawings]

[0013] [Figure 1] 1 is a cross-sectional view of an electric motor according to an embodiment; [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 3 is an enlarged view of part III in FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 5 is a cross-sectional view taken along line VV in FIG. 4. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0015] As shown in Fig. 1 and Fig. 2, the electric motor 1 includes a shaft 2, a rotor 3, a stator 4, a case 5, and a bearing 6. The electric motor 1 is, for example, a motor. The electric motor 1 is mounted on, for example, an automobile or an aircraft. The electric motor 1 is, for example, a drive source for a fuel pump. The electric motor 1 may also be, for example, a generator.

[0016] The shaft 2 has, for example, a cylindrical shape. The shaft 2 has an axis Ax. The shaft 2 is rotatable about the axis Ax. The rotor 3 has, for example, a cylindrical shape with the axis Ax as its center line. The inner peripheral surface of the rotor 3 is fixed to the outer peripheral surface of the shaft 2. The rotor 3 has, for example, a permanent magnet.

[0017] The stator 4 is disposed on the outside of the rotor 3. The stator 4 includes a stator core 41 and a coil member 42. The stator core 41 is, for example, a split core. The stator core 41 includes a yoke 43 and a plurality of teeth 44. The yoke 43 is, for example, cylindrical with the axis Ax as its center line. The yoke 43 is a partial region of the stator core 41.

[0018] The teeth 44 are, for example, rectangular prism-shaped. The width of the teeth 44 in the axial direction of the shaft 2 (direction parallel to the axis Ax) is longer than the width of the teeth 44 in the rotational direction of the shaft 2. The teeth 44 protrude from the inner circumferential surface of the yoke 43. The teeth 44 are arranged at predetermined intervals in the rotational direction of the shaft 2. Slots (spaces) are formed between adjacent teeth 44. The teeth 44 are a partial region of the stator core 41. The teeth 44 are integrally formed with the yoke 43 using the same material. The stator core 41 is, for example, formed from a soft magnetic material. The material of the stator core 41 is, for example, a laminated iron core or a powdered iron core.

[0019] The coil member 42 has, for example, a cylindrical shape with a center line parallel to a radial direction of the shaft 2. The cross section of the coil member 42 in a plane perpendicular to the radial direction of the shaft 2 has, for example, a rectangular ring shape. The width of the coil member 42 in the axial direction of the shaft 2 is longer than the width of the coil member 42 in the rotation direction of the shaft 2. The coil member 42 surrounds the teeth 44. The coil member 42 is attached to the teeth 44 from the opposite side of the teeth 44 to the yoke 43. In other words, the teeth 44 are inserted into the coil member 42. When an alternating current is supplied to the coil member 42, a rotating magnetic field is generated. The rotor 3 rotates due to the action of the torque generated by this rotating magnetic field. When the rotor 3 rotates, the shaft 2 also rotates following the rotor 3.

[0020] The case 5 houses the rotor 3, the stator 4, etc. The case 5 has, for example, a cylindrical shape with the axis Ax as the center line. The stator 4 is fixed to the inner peripheral surface of the case 5. The bearings 6 are provided at both ends of the case 5 in the axial direction of the shaft 2. The shaft 2 is supported by the case 5 via the bearings 6. Note that a cooling jacket for cooling the stator 4 may be housed inside the case 5. The cooling jacket may have a cylindrical shape surrounding the stator 4. The cooling jacket may be fixed to the inner peripheral surface of the case 5.

[0021] 3, the coil member 42 has a coil 45 and a mold 46. The coil 45 extends in a spiral shape so as to be wound around the teeth 44. The width of the coil 45 in the axial direction of the shaft 2 is greater than the width of the coil 45 in the rotational direction of the shaft 2. The coil 45 is, for example, a rectangular coil. The coil 45 is, for example, a so-called edgewise coil.

[0022] The coil 45 has a plurality of coil conductors stacked on top of each other. When viewed from the stacking direction, the coil conductors have, for example, a rectangular ring shape. The coil conductors have a plate shape. The width of the sides of the coil conductors is greater than the thickness of the coil conductors. The ends of the coil conductors adjacent in the stacking direction are connected to each other. The coil conductors adjacent in the stacking direction are separated from each other. The material of the coil 45 is, for example, copper or aluminum.

[0023] The mold 46 encases the coil 45. The mold 46 encases the entire surface area of ​​the coil 45. The mold 46 is in contact with the entire surface area of ​​the coil 45. The mold 46 is also present between each coil conductor. The coil 45 is not exposed from the mold 46. The surface of the coil member 42 is formed by the mold 46.

[0024] The mold 46 is in direct contact with the coil 45. In this embodiment, the mold 46 is in direct contact with the entire surface area of ​​the coil 45. The mold 46 and the coil 45 are integrally formed. The mold 46 and the coil 45 are each a partial area of ​​the integrated coil member 42. The mold 46 and the coil 45 are connected to each other. There is no intervening material between the mold 46 and the coil 45. Note that there may be an unintended foreign material between the mold 46 and the coil 45. The coil member 42 is manufactured by, for example, a three-dimensional modeling method. The mold 46 and the coil 45 are simultaneously modeled by a three-dimensional modeling method.

[0025] The mold 46 contains diamond. In this embodiment, the mold 46 contains only diamond. That is, the mold 46 is made of diamond. The mold 46 does not contain any component other than diamond. The mold 46 does not contain any component whose thermal conductivity is smaller than that of diamond. The mold 46 does not contain, for example, resin. The mold 46 may contain, as a component other than diamond, a component whose thermal conductivity is equal to or greater than that of diamond. Also, there may be cases where unintended foreign matter is present in the mold 46.

[0026] The integrated coil member 42 is attached to the teeth 44. A gap S exists between the teeth 44 and the coil member 42. The outer periphery of the teeth 44 is shorter than the inner periphery of the coil member 42. When the coil member 42 is attached to the teeth 44, the inner wall surface of the coil member 42 includes an area separated from the teeth 44. In other words, the coil member 42 includes an area that does not contact the teeth 44.

[0027] 4 and 5, the mold 46 includes a main body portion 465 and a pair of side wall portions 466. The main body portion 465 is located inside the yoke 43. The coil 45 is surrounded by the main body portion 465. The pair of side wall portions 466 are located on both sides of the yoke 43 in the axial direction of the shaft 2. The pair of side wall portions 466 sandwich the yoke 43 in the axial direction of the shaft 2.

[0028] The mold 46 includes a cooling flow passage 460. The cooling flow passage 460 includes an outer region 461 and an inner region 462. In this embodiment, the cooling flow passage 460 is provided facing the coil ends on both axial sides of the coil 45. Therefore, one side and the other side of the coil end are sandwiched between the outer region 461 and the inner region 462, respectively. The outer region 461 is located outside the coil 45 in the axial direction of the shaft 2 (the length direction of the coil 45). In this embodiment, the outer region 461 is formed across the main body portion 465 and the side wall portion 466 of the mold 46. The outer region 461 may cover an area larger than the projection of the coil 45 when viewed from the axial direction of the shaft 2. In other words, the outer edge of the outer region 461 may be located outside the outer edge of the coil 45 when viewed from the axial direction of the shaft 2.

[0029] 5, the outer region 461 extends to the vicinity of the outer edge of the mold 46 when viewed in the axial direction of the shaft 2. The outer region 461 includes an opening 461a that opens to an end face 46a of the side wall portion 466. In this embodiment, the opening 461a opens toward the radially outer side of the yoke 43. The outer region 461 is connected to an external flow passage via the opening 461a. The opening 461a may be an inlet or an outlet for the refrigerant into the outer region 461.

[0030] 6, the inner region 462 extends to the vicinity of the outer edge of the mold 46 so as not to overlap with the coil 45 when viewed in the axial direction of the shaft 2. The inner region 462 includes an opening 462a that opens into the end face 46a of the side wall portion 466. The inner region 462 is connected to an external flow passage through the opening 462a. The inner region 462 and the outer region 461 are connected to each other through the region on the tip side of the teeth 44.

[0031] As described above, the coil member 42 has the mold 46 that wraps the coil 45 so as to be in direct contact with the coil 45 and includes the cooling passage 460. This allows the coil 45 to be cooled by the refrigerant flowing through the cooling passage 460. Moreover, the mold 46 is made of diamond. Since diamond has electrical insulation properties, an aqueous refrigerant can be used as the refrigerant flowing through the cooling passage 460. Therefore, the cooling efficiency of the coil 45 can be improved compared to, for example, a case where an oil-based refrigerant is used. In addition, since the thermal conductivity of diamond is relatively large, the cooling efficiency of the coil 45 can be improved compared to, for example, a case where the mold contains a resin. Therefore, according to the stator 4, the cooling efficiency of the coil can be improved.

[0032] Conventionally, a mold encasing the coil was formed by pouring a liquid resin having fluidity into the coil. Therefore, the mold contained a resin that is relatively easy to ensure fluidity. However, in this embodiment, the coil member 42 is formed by a three-dimensional modeling method, so the material of the mold 46 does not need to have fluidity. Therefore, the mold could be made of diamond, which has high thermal conductivity.

[0033] The coil 45 is a rectangular coil, which allows the coil member 42 to be easily manufactured by a three-dimensional modeling method.

[0034] A gap S exists between the teeth 44 and the coil member 42. This allows the coil member 42 to be appropriately attached to the teeth 44.

[0035] The cooling flow passage 460 includes an outer region 461 located outside the coil 45. This makes it possible to ensure the volume of the cooling flow passage 460. In addition, since the outer region 461 is located outside the coil 45, three-dimensional modeling of the coil member 42 becomes easy.

[0036] The cooling flow passage 460 includes an inner region 462 located inside the coil 45. This allows the coil 45 to be efficiently cooled from the inside of the coil 45. Because there is a gap S between the teeth 44 and the coil member 42, heat from the coil 45 is less likely to be transmitted to the teeth 44 compared to, for example, a case in which the coil member 42 is in contact with the teeth 44. In this embodiment, because there is an inner region 462 between the coil 45 and the teeth 44, even if heat from the coil 45 is less likely to be transmitted to the teeth 44, the coil 45 can be efficiently cooled.

[0037] Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment.

[0038] The cooling passage 460 does not have to include the inner region 462. The cooling passage 460 does not have to include the outer region 461. It is sufficient that the mold 46 includes the cooling passage.

[0039] Moreover, the cooling passage 460 may be provided opposite to a coil end on one side of the coil 45 . [Note] The present disclosure relates to <1> "A stator comprising teeth and coil members attached to the teeth, the coil members having a coil extending in a spiral manner so as to be wound around the teeth, and a mold encasing the coil so as to be in direct contact with the coil and including a cooling passage, the mold being constructed from diamond."

[0040] The present disclosure relates to <2> "The coil is a rectangular coil, <1> The stator described in the above.

[0041] The present disclosure relates to <3> "There is a gap between the teeth and the coil member, <1> or <2> The stator described in the above.

[0042] The present disclosure relates to <4> "The cooling passage includes an outer region located outside the coil, <1> ~ <3> The present invention relates to a stator according to any one of the above.

[0043] The present disclosure relates to <5> "The cooling passage includes an inner region located inside the coil, <1> ~ <4> The present invention relates to a stator according to any one of the above. [Explanation of symbols]

[0044] 4 Stator 42 Coil parts 44 Teeth 45 Coil 46 Mold 460 Cooling Channel 461 Outer area 462 Inner area S Gap

Claims

1. Teeth and A coil member attached to the teeth, The coil member includes: a coil extending in a spiral shape so as to be wound around the teeth; a mold that encases the coil in direct contact with the coil and includes cooling channels; The mold is made of diamond.

2. The stator according to claim 1 , wherein the coil is a rectangular coil.

3. The stator according to claim 1 , wherein a gap exists between the teeth and the coil members.

4. The stator of claim 1 , wherein the cooling passage includes an outer region located outside the coils.

5. The stator of claim 1 , wherein the cooling passage includes an inner region located inside the coils.

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