Stator of an axial gap motor

Abstract

The goal is to improve the cooling of the stator. [Solution] A stator for an axial gap motor, characterized by comprising: a stator core having a plurality of salient poles arranged in the circumferential direction; a partition member separating one axial side and the other axial side of the salient poles; and a refrigerant flow path that allows refrigerant to flow from the axial side of the salient poles separated by the partition member to the other axial side of the salient poles separated by the partition member.

Description

Technical Field

[0001] The present invention relates to a stator of an axial gap motor.

Background Art

[0002] Conventionally, a structure for cooling an axial gap motor has been known. Patent Document 1 discloses a structure in which a coolant introduction port is provided at one location on the outer periphery of the stator of an axial gap motor, and a coolant discharge port is provided at one location that traverses half of the outer periphery of the stator from this introduction port. In Patent Document 1, coolant is introduced from the introduction port into a closed space that encircles the outer diameter side of the stator, and the coolant that has passed through this closed space is discharged from the discharge port, thereby cooling the stator from the outer diameter side.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, since the coolant introduced from the introduction port absorbs the heat of the stator when passing through the closed space that encircles the outer diameter side of the stator, the temperature of the coolant differs between the vicinity of the introduction port and the vicinity of the discharge port, resulting in a difference in cooling efficiency and uneven temperature of the stator. For this reason, conventionally, there has been room for improvement in the cooling of the stator.

[0005] The present invention has been made in view of the above points, and an object thereof is to improve the cooling of the stator.

Means for Solving the Problems

[0006] A stator according to one aspect of the present invention is a stator for an axial gap motor, characterized by comprising: a stator core having a plurality of salient poles arranged in the circumferential direction; a partition member separating one axial side and the other axial side of the salient poles; and a refrigerant flow path for flowing refrigerant from the axial side of the salient poles separated by the partition member to the other axial side of the salient poles separated by the partition member. [Effects of the Invention]

[0007] According to one aspect of the present invention, stator cooling can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view of the stator 100 according to Embodiment 1 of the present invention. [Figure 2] This is an exploded perspective view of the stator 100. [Figure 3] This is a perspective view showing winding 150, stator core 160, bobbin 170, and winding 180. [Figure 4] This is a partial cross-sectional perspective view of stator 100. [Figure 5] This is a perspective view showing a bobbin 1170 according to Embodiment 2 of the present invention. [Figure 6] This is a perspective view showing a stator core 1160 according to Embodiment 3 of the present invention. [Modes for carrying out the invention]

[0009] The stator of an axial gap motor according to an embodiment of the present invention will be described below with reference to the drawings. Note that in the following drawings, the scale and number of components in each structure may differ from the actual structure in order to make the components easier to understand.

[0010] <Embodiment 1> Figure 1 is a perspective view of a stator 100 according to Embodiment 1 of the present invention. Figure 2 is an exploded perspective view of the stator 100. The stator 100 is the stator of an axial gap motor. The axial gap motor having the stator 100 rotates around a shaft (not shown) extending along a central axis J as its axis of rotation. The axial gap motor having the stator 100 has one or more rotors (not shown) on one or both sides of the stator 100 in the axial direction, which is the direction in which the central axis J extends.

[0011] In the following explanation, unless otherwise specified, the direction parallel to the central axis J will simply be called the "axial direction," the radial direction centered on the central axis J will simply be called the "radial direction," and the circumferential direction centered on the central axis J, that is, the direction around the axis of the central axis J, will simply be called the "circumferential direction." In the axial direction, the left side of Figure 1 will be called the "one axial side," and the right side of Figure 1 will be called the "other axial side." In the radial direction, the side approaching the central axis J will be called the "inner radial side," and the side moving away from the central axis J will be called the "outer radial side." In the circumferential direction, when looking from the left side (one axial side) to the right side (the other axial side) of Figure 1, the clockwise side will be called the "one circumferential side," and the counterclockwise side will be called the "other circumferential side."

[0012] In this specification, "extending in the axial direction" includes not only cases where the material extends strictly in the axial direction, but also cases where the material extends in a direction inclined to the axial direction by an angle of less than 45°. Furthermore, in this specification, "extending radially" includes not only cases where the material extends strictly radially, i.e., perpendicular to the axial direction, but also cases where the material extends in a direction inclined to the radial direction by an angle of less than 45°. Furthermore, "parallel" includes not only cases where the material is strictly parallel, but also cases where the angle between the material and the material is inclined to each other by an angle of less than 45°. Furthermore, "spreading in a direction perpendicular to the axial direction" includes not only cases where the material spreads in a direction perpendicular to the axial direction, but also cases where the material spreads in a direction inclined to the direction perpendicular to the axial direction by an angle of less than 45°.

[0013] The stator 100 includes a first stator case 110, a second stator case 120, a third stator case 130, a fourth stator case 140, windings 150, a stator core 160, bobbins 170, windings 180, a fifth stator case 190, and a sixth stator case 200.

[0014] Figure 3 is a perspective view showing the winding 150, stator core 160, bobbin 170, and winding 180. The stator 100 has a plurality of stator cores 160 arranged at equal intervals in the circumferential direction. Each of the plurality of stator cores 160 plays the role of a salient pole of the stator 100. The stator core 160 has a surface 162 which is the axial side and a surface 161 which is the axial side. The bobbin 170 is made of an insulator such as resin. The bobbin 170 is constructed by arranging the same number of segmented bobbins 171 as the number of stator cores 160 in the circumferential direction. The segmented bobbins 171 are fixed and sealed together, for example, with adhesive. The segmented bobbin 171 has a housing portion 172 that protrudes to one side in the axial direction and to the other side in the axial direction. The housing portion 172 has a through hole 173 that penetrates in the axial direction. The stator core 160 is positioned to pass through the through-hole 173 of the housing 172 and is housed in the housing 172. The winding 150 is wound around one axial side of the housing 172. The winding 180 is wound around the other axial side of the housing 172. The bobbin 170 is interposed at least between the stator core 160 and the windings 150 and 180.

[0015] Referring to Figures 1 and 2, the fourth stator case 140 is positioned radially inward of the bobbin 170, with a gap between it and the bobbin 170. The fourth stator case 140 is a ring-shaped member. For example, the shaft of an axial gap motor is positioned radially inward of the fourth stator case 140.

[0016] The third stator case 130 is disposed radially outside the bobbin 170. The third stator case 130 is a ring-shaped member. The third stator case 130 has a through hole 131 that penetrates radially on one axial side, and a through hole 132 that penetrates radially on the other axial side. A plurality of through holes 131 and 132 are provided in the circumferential direction. The through hole 131 and the through hole 132 are offset in the circumferential direction. By this, the strength of the third stator case 130 can be ensured as compared with the case where the through hole 131 and the through hole 132 are not offset in the circumferential direction. In the present embodiment, the number of each of the through holes 131 and 132 is the same as the number of stator cores 160.

[0017] The second stator case 120 is disposed on one axial side of the stator core 160. The second stator case 120 has a through hole 121 that penetrates in the axial direction. One axial side end of the stator core 160 fits into the through hole 121, and the surface 162 of the stator core 160 is exposed on one axial side.

[0018] The sixth stator case 200 is disposed on the other axial side of the stator core 160. The sixth stator case 200 has a through hole 201 that penetrates in the axial direction. The other axial side end of the stator core 160 fits into the through hole 201, and the surface 161 of the stator core 160 is exposed on the other axial side.

[0019] The first stator case 110 is disposed radially outside the second stator case 120 and the third stator case 130. The first stator case 110 has a refrigerant inlet 111 that is an inlet of refrigerant into the stator 100, and a refrigerant outlet 112 that is an outlet of refrigerant from the stator 100. The refrigerant inlet 111 is disposed radially inside the refrigerant outlet 112. The refrigerant is, for example, a coolant. A plurality of refrigerant inlets 111 and refrigerant outlets 112 are arranged in the circumferential direction, and are configured to supply refrigerant into the stator 100 from a plurality of locations in the circumferential direction. In the present embodiment, the number of each of the refrigerant inlets 111 and the refrigerant outlets 112 is the same as the number of stator cores 160.

[0020] The fifth stator case 190 is disposed radially outside the third stator case 130. The fifth stator case 190 is axially sandwiched between the first stator case 110 and the sixth stator case 200. The outer peripheral surface of the fifth stator case 190 is exposed to the outside and has cooling fins 191. The fifth stator case 190 is preferably made of a material with high thermal conductivity and good heat dissipation.

[0021] FIG. 4 is a partial cross-sectional perspective view of the stator 100. The first stator case 110 has a partition wall 113 that separates a refrigerant flow path connecting from the refrigerant inlet 111 to the through hole 131 and a refrigerant flow path connecting from the through hole 132 to the refrigerant outlet 112. Also, the bobbin 170 separates the winding 150 side and the winding 180 side. The refrigerant flowing into the stator 100 from the refrigerant inlet 111 passes through the through hole 131 of the third stator case 130 and flows around the winding 150 wound around the stator core 160 on one axial side of the bobbin 170. Then, the refrigerant flows from one axial side to the other axial side of the partition of the bobbin 170 through the gap between the radially inner end of the bobbin 170 and the radially outer end of the fourth stator case 140. Then, the refrigerant flows around the winding 180 wound around the stator core 160 on the other axial side of the bobbin 170, passes through the through hole 132 of the third stator case 130, and flows out of the stator 100 from the refrigerant outlet 112. Due to this refrigerant flow, the stator core 160 is cooled by the refrigerant through the windings 150 and 180.

[0022] The gap between the radially inner end of the bobbin 170 and the radially outer end of the fourth stator case 140 is an example of a refrigerant flow path that allows refrigerant to flow from one axial side of the stator core 160 partitioned by the bobbin 170 to the other axial side of the stator core 160 partitioned by the bobbin 170.

[0023] In the present embodiment, the bobbin 170 separates the winding 150 side and the winding 180 side, thereby enabling the formation of a refrigerant flow path. It is desirable to provide a sealing material such as a resin member or an adhesive at the positions where the components contact each other so that refrigerant does not leak at locations other than the refrigerant flow path described above.

[0024] In the refrigerant flow path within the stator 100, the through-holes 131 and 132 are offset in the circumferential direction, which allows for circumferential movement in the refrigerant flow and enables efficient cooling of the area around the stator core 160.

[0025] The refrigerant that flows out of the stator 100 through the refrigerant outlet 112 flows back into the stator 100 through the refrigerant inlet 111 via a pump and refrigerant flow path (not shown) and circulates. The refrigerant is cooled by heat exchange when it comes into contact with the inner surface of the fifth stator case 190 as it flows out of the stator 100 through the refrigerant outlet 112. In addition, the refrigerant may be cooled by providing a cooling means such as a cooler outside the stator 100.

[0026] In this embodiment, the refrigerant inlet 111 and refrigerant outlet 112 are provided on one axial side of the stator 100. However, the present invention is not limited to this, and the refrigerant inlet and outlet may be provided at other locations, such as the other axial side of the stator 100, the radially outer side, or the radially inner side. Furthermore, the refrigerant may be configured to flow from the refrigerant outlet 112 towards the refrigerant inlet 111.

[0027] According to this embodiment, by using the bobbin 170 as a partition member to separate the winding 150 side from the winding 180 side, a refrigerant flow path is formed that returns from the refrigerant flow path on one axial side of the bobbin 170 to the refrigerant flow path on the other axial side. This makes it possible to eliminate temperature unevenness in the stator core 160.

[0028] According to this embodiment, the stator 100 can be made lighter by forming the bobbin 170, which is a partition member separating the winding 150 side and the winding 180 side, out of resin.

[0029] Furthermore, it is desirable to provide sealing materials such as resin components or adhesives at the contact points between each component in the refrigerant flow path described above in order to prevent refrigerant leakage.

[0030] Furthermore, according to this embodiment, since refrigerant is introduced into the stator 100 from multiple refrigerant inlets 111 in the circumferential direction, multiple windings can be uniformly cooled in the circumferential direction without temperature unevenness occurring, thereby improving cooling efficiency.

[0031] <Embodiment 2> Figure 5 is a perspective view showing a bobbin 1170 according to Embodiment 2 of the present invention. Embodiment 2 has a bobbin 1170 instead of the bobbin 170 in Embodiment 1. In other respects, Embodiment 2 is the same as Embodiment 1.

[0032] The bobbin 170 of Embodiment 1 was a bobbin formed by combining multiple divided bobbins 171, but the bobbin 1170 of Embodiment 2 is an integrated bobbin. The bobbin 1170 is made of an insulator such as resin. The bobbin 1170 has a partition portion 1171 that separates the winding 150 side from the winding 180 side. The bobbin 1170 has housing portions 1172 that protrude to one side in the axial direction and to the other side in the axial direction. The housing portion 1172 has a through hole 1173 that penetrates in the axial direction. The stator core 160 is arranged to penetrate the through hole 1173 of the housing portion 1172 and is housed in the housing portion 1172. The winding 150 is wound around the one side of the housing portion 1172 in the axial direction. The winding 180 is wound around the other side of the housing portion 1172 in the axial direction. The bobbin 1170 is interposed at least between the stator core 160 and the windings 150 and 180.

[0033] According to Embodiment 2, there is no need to combine the divided bobbins 171 with each other, and sealing between adjacent divided bobbins 171 is unnecessary.

[0034] According to Embodiment 2, the bobbin 1170 is used as a partition member to separate the winding 150 side from the winding 180 side, thereby forming a refrigerant flow path that folds back from the refrigerant flow path on one axial side of the bobbin 1170 to the refrigerant flow path on the other axial side. This makes it possible to eliminate temperature unevenness in the stator core 160.

[0035] According to Embodiment 2, the stator 100 can be made lighter by forming the bobbin 1170, which is a partition member separating the winding 150 side and the winding 180 side, out of resin.

[0036] <Embodiment 3> Figure 6 is a perspective view showing a stator core 1160 according to Embodiment 3 of the present invention. In Embodiment 1, the winding 150 side and the winding 180 side are separated by a bobbin 170. In Embodiment 3, the stator core 1160 separates the winding 150 side and the winding 180 side.

[0037] The stator core 1160 has a partition portion 1161 that separates the winding 150 side from the winding 180 side. The stator core 1160 has protrusions 1162 that project in one axial direction and in the other axial direction. The axial end of the protrusion 1162 fits into the through hole 121, and the surface 1164 of the protrusion 1162 is exposed in one axial direction. The axial end of the protrusion 1162 fits into the through hole 201, and the surface 1163 of the protrusion 1162 is exposed in the other axial direction. Each of the multiple protrusions 1162 of the stator core 1160 plays the role of a salient pole of the stator 100.

[0038] A winding 150 is wound around one axial side of the protrusion 1162 via a bobbin (not shown). A winding 180 is wound around the other axial side of the protrusion 1162 via a bobbin (not shown). The bobbin (not shown) is interposed at least between the stator core 1160 and the windings 150 and 180.

[0039] According to Embodiment 3, the stator core 1160 is integrated with a partition portion 1161 that separates the winding 150 side from the winding 180 side, thus reducing the number of parts compared to the case where multiple stator cores 160 are used.

[0040] According to Embodiment 3, the stator core 1160 is used as a partition member to separate the winding 150 side from the winding 180 side, thereby forming a refrigerant flow path that folds back from the refrigerant flow path on one axial side of the stator core 1160 to the refrigerant flow path on the other axial side. This eliminates temperature unevenness in the stator core 1160.

[0041] According to this embodiment, by forming the partition portion 1161 of the stator core 1160, which is a partition member separating the winding 150 side and the winding 180 side, thin in the axial direction, the stator 100 can be made lighter, and the effect of short-circuiting of magnetic flux between the rotor magnet and the partition portion 1161 can also be reduced.

[0042] The present invention is not limited to the embodiments described above, and various improvements and design modifications may be made without departing from the spirit of the invention. In addition, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the above description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0043] 100...Status 110...First stator case 120...Second stator case 130...Third stator case 140…Fourth stator case 150...winding 160... Stator core 170... Bobbin 180...winding 190…5th stator case 200...6th stator case

Claims

1. The stator of an axial gap motor, A stator core having multiple salient poles arranged in the circumferential direction, A partition member that separates one axial side and the other axial side of the salient pole, A refrigerant flow path is provided for flowing refrigerant from one axial side of the salient pole separated by the partition member to the other axial side of the salient pole separated by the partition member, A stator characterized by having the following features.

2. The stator core has the partition member The stator according to feature 1.

3. The salient pole and the winding wrapped around the salient pole, A bobbin interposed between at least the salient pole and the winding, It has, The bobbin has the partition member The stator according to feature 1.

4. The bobbin consists of a plurality of segmented bobbins divided in the circumferential direction. The stator according to feature 3.

5. A refrigerant inlet for introducing refrigerant into one axial side of the salient pole, A refrigerant outlet that discharges the refrigerant from the other axial side of the salient pole, It has, Multiple refrigerant inlets and outlets are arranged in the circumferential direction. The stator according to feature 1.

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