Stator structure and rotating electrical machine

Abstract

The purpose of the present invention is to improve the degree of freedom of a slip ring and a frame of a rotating electrical machine. A stator structure is provided with: a stator having a stator core and a stator coil wound around the stator core; the collector ring is provided with a bus bar connected with the stator coil; a frame that accommodates the stator core on the inside in the radial direction, and that has a flow path for a refrigerant liquid that opens at one end in the axial direction and extends toward the other end in the axial direction; a cover member that is disposed on one side in the axial direction of the frame and on the other side in the axial direction of the slip ring, and that closes the opening of the flow path; and a holding structure that holds the collector ring on the cover member.

Description

Technical Field

[0001] The present invention relates to a stator structure and a rotating electric machine. Background Art

[0002] For example, in a three-phase AC motor, the following structure is known: stator coils of each phase wound around a stator core are connected by a bus bar for each phase, and the bus bars for each phase are collected by slip rings (for example, Patent Document 1). The bus bar is a ring-shaped conductor.

[0003] In addition, as a cooling structure of a motor, the following structure is known: a flow path is provided in a frame covering the outer periphery of the stator, and a refrigerant liquid such as water is made to flow in the flow path to cool the stator and the like (for example, Patent Document 2).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-154084

[0007] Patent Document 2: International Publication No. 2013 / 069321 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] A frame of a motor is manufactured using a mold such as an aluminum die-cast. In this case, in order to form a flow path in the frame, the flow path needs to be shaped to open to the outside of the frame for demolding. In order to cool the stator axially, the flow path needs to extend axially. In this case, the opening for demolding is arranged at the axial end of the frame.

[0010] In addition, in the case of a motor for automotive drive or the like, in order to prevent breakage of the slip ring caused by vibration or the like, it is preferable to hold the slip ring at a holding point. Since the slip ring is arranged at the axial end of the stator, it is considered to set the holding point of the slip ring at the axial end of the frame. However, as described above, since there is an opening of the flow path at the axial end of the frame, the holding point must be arranged avoiding the opening. In this way, the degrees of freedom of the slip ring and the frame are low, and there is a problem such as an obstacle to downsizing of the size.

[0011] An object of the present invention is to improve the degrees of freedom of the slip ring and the frame of a rotating electric machine.

[0012] Means for Solving the Problems

[0013] One embodiment of the stator structure of the present invention includes: a stator having a stator core and a stator coil wound around the stator core; a slip ring having a bus bar connected to the stator coil; a frame that houses the stator core on the radially inner side and has a flow path for refrigerant liquid that opens at one axial end and extends to the other axial side; a cover member that is disposed on the one axial side of the frame and on the other axial side of the slip ring and closes the opening of the flow path; and a holding structure that holds the slip ring to the cover member.

[0014] In the stator structure of the above embodiment, the holding structure fixes the cover member and the slip ring with bolts.

[0015] One embodiment of the rotating electric machine of the present invention includes: the above-described stator structure; a rotor that is disposed on the radially inner side of the stator core; and an inverter unit that is disposed on the one axial side of the stator structure and drives the rotating electric machine.

[0016] The rotating electric machine of the above embodiment is used for driving an automobile.

[0017] Advantages of the Invention

[0018] According to one embodiment of the present invention, the degrees of freedom of the slip ring and the frame of the rotating electric machine can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic exploded perspective view showing the stator structure of the first embodiment of the present invention.

[0020] Figure 2 is showing Figure 1 a side cross-sectional view of the assembled state of the stator structure 100.

[0021] Figure 3 is showing Figure 1 a perspective view of the cover member 120. DETAILED DESCRIPTION

[0022] Hereinafter, the stator structure of the embodiment of the present invention will be described with reference to the drawings. In the following drawings, in order to facilitate understanding of each structure, the actual structure, the scale, the number, etc. in each structure may sometimes be different. In addition, in order to easily observe each structure, it is schematically shown in a shape different from the actual shape.

[0023] In addition, in the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the X-axis direction is the direction parallel to the axial direction of the central axis J shown in Figure 1 . The Y-axis direction is the radial direction with respect to the central axis J in Figure 1The up-down direction. The Z-axis direction is a direction orthogonal to both the X-axis direction and the Y-axis direction. In any of the X-axis direction, Y-axis direction, and Z-axis direction, the side pointed by the arrow shown in the figure is the + side, and the opposite side is the - side.

[0024] In addition, in the following description, the negative side (-X side) of the X-axis direction is referred to as "one side", and the positive side (+X side) of the X-axis direction is referred to as "the other side". In addition, one side and the other side are just names used for explanation and do not limit the actual positional relationship and direction. In addition, unless otherwise specified, the direction parallel to the central axis J (X-axis direction) is simply referred to as the "axial direction", the radial direction centered on the central axis J is simply referred to as 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 is simply referred to as the "circumferential direction". The side closer to the central axis J in the radial direction is referred to as the "radial inner side", and the side farther from the central axis J is referred to as the "radial outer side".

[0025] In addition, in this specification, "extending along the axial direction" includes not only the case of strictly extending along the axial direction (X-axis direction), but also the case of extending along a direction inclined within a range of less than 45° with respect to the axial direction. In addition, in this specification, "extending along the radial direction" includes not only the case of strictly extending along the radial direction, that is, the direction perpendicular to the axial direction (X-axis direction), but also the case of extending along a direction inclined within a range of less than 45° with respect to the radial direction. In addition, "parallel" includes not only the case of being strictly parallel, but also the case where the angle formed with each other is inclined within a range of less than 45°.

[0026] <First Embodiment>

[0027] Figure 1 is a schematic exploded perspective view showing the stator structure of the first embodiment of the present invention. The stator structure 100 constitutes the periphery of the stator of a motor as an example of a rotating electric machine. The stator structure 100 constitutes, for example, a three-phase AC motor. The stator structure 100 is configured to include a stator 110, a cover member 120, a frame 130, a slip ring 113, and a terminal block 114. The motor having the stator structure 100 has a rotor disposed on the radial inner side of the stator 110, but the illustration of the rotor is omitted.

[0028] The stator 110 has a cylindrical stator core 111 and stator coils 112 wound around each phase of the stator core 111. The slip ring 113 has bus bars 113a for each phase. The end portions of the stator coils 112 of each phase are electrically connected to the bus bars 113a of each phase. The outer diameter of the slip ring 113 is larger than the outer diameter of the stator core 111. The outer peripheral end of the slip ring 113 is located at a position radially outside the outer peripheral end of the stator core 111.

[0029] The terminal block 114 holds the respective terminals 113b of the busbars 113a for each phase, enabling easy connection to the outside. An inverter unit for driving the motor is disposed on one axial side of the motor having the stator structure 100, and each terminal of the terminal block 114 is electrically connected to the inverter unit. The motor having the stator structure 100 is used, for example, for driving an automobile.

[0030] The frame 130 has a cylindrical shape and houses the stator core 111 on the radially inner side. The frame 130 and the stator core 111 are fixed, for example, by press-fitting. The frame 130 has a flow path 131 that serves as a flow path for the refrigerant liquid. The refrigerant liquid is, for example, water. The flow path 131 opens at one axial end of the frame 130 and extends from the opening to the other axial side. The frame 130 is manufactured using a mold, for example, by die casting of aluminum. By having the flow path 131 open at one axial end of the frame 130, the shape of the flow path 131 can be demolded when manufacturing the frame 130.

[0031] The cover member 120 is a member that seals the opening at one axial end of the frame 130 as a cover in such a way as to prevent the refrigerant liquid from leaking from the opening at one axial end of the frame 130 when the refrigerant liquid flows through the flow path 131. The cover member 120 is disposed on one axial side of the frame 130 and on the other axial side of the slip ring 113. The cover member 120 is an annular member, and by having a surface at a position facing the opening at one axial end of the frame 130, the opening is sealed when fixed to one axial end of the frame 130. Around the opening, a sealing portion formed of a liquid gasket or the like is preferably provided between the frame 130 and the cover member 120. The stator 110 is cooled by flowing the refrigerant liquid through the flow path 131. The refrigerant liquid in the flow path 131 circulates, for example, via an inlet and an outlet provided on the side surface of the frame 130 by a pump or the like.

[0032] The stator structure 100 has a bolt 120c. The cover member 120 has a bolt hole 120b into which the bolt 120c is inserted. The frame 130 has a bolt hole 130a into which the bolt 120c is inserted. The bolt 120c fixes and holds the cover member 120 to the frame 130 in such a way that the surface on the other axial side of the cover member 120 contacts the surface on one axial side of the frame 130. The bolt 120c, the bolt hole 120b, and the bolt hole 130a are an example of a holding structure for holding the cover member 120 to the frame 130. The bolt 120c, the bolt hole 120b, and the bolt hole 130a are provided in a plurality in the circumferential direction.

[0033] The stator structure 100 has a bolt 113d. The slip ring 113 has a bolt hole 113c into which the bolt 113d is inserted. The cover member 120 has a bolt hole 120a into which the bolt 113d is inserted. The bolt 113d fixes and holds the slip ring 113 to the cover member 120 in such a manner that the surface on the other axial side of the slip ring 113 contacts the surface on the one axial side of the cover member 120. The bolt 113, the bolt hole 113c, and the bolt hole 120a are an example of a holding structure for holding the slip ring 113 to the cover member 120. The bolt 113, the bolt hole 113c, and the bolt hole 120a are provided in plurality in the circumferential direction.

[0034] The stator structure 100 has a bolt 114a. The cover member 120 has a bolt hole 120d into which the bolt 114a is inserted. The terminal block 114 is fixed to the cover member 120 by the bolt 114a. The bolt 114a and the bolt hole 120d are provided on both circumferential sides of the terminal block 114.

[0035] Figure 2 It shows the Figure 1 side cross-sectional view of the assembled state of the stator structure 100. Figure 2 It is shown by being sectioned along a plane passing through the central axis J and orthogonal to the Z axis. The one axial side of the stator core 112 may also be covered by a bracket from the one axial side and the radial outside. This bracket is bolted to the frame 130 or the cover member 120 at a position different from the bolt fixing positions of the frame 130 and the cover member 120.

[0036] The slip ring 113 is disposed radially outside the coil end portion on the one axial side of the stator coil 112. At least a part of the slip ring 113 overlaps with the cover member 120 in the axial direction. At least a part of the cover member 120 overlaps with the frame 130 in the axial direction. In addition, the radial length of the other axial side of the flow path 131 is shorter than the radial length of the one axial side. By setting it to such a shape, the demolding of the shape of the flow path 131 is made smooth when manufacturing the frame 130.

[0037] Figure 3 It shows the Figure 1 perspective view of the cover member 120. In the present embodiment, six bolt holes 120b are circumferentially arranged in the cover member 120. That is, a combination of six bolts 120c, bolt holes 120b, and bolt holes 130a is arranged in the circumferential direction. The number of the bolts 120c, the bolt holes 120b, and the bolt holes 130a is not limited to this, as long as the opening of the flow path 131 of the frame 130 can be stably blocked by the cover member 120.

[0038] In addition, in the present embodiment, three bolt holes 120a are circumferentially arranged in the cover member 120. That is, a combination of three bolts 113d, bolt holes 113c, and bolt holes 120a is arranged in the circumferential direction. The number of the bolts 113d, bolt holes 113c, and bolt holes 120a is not limited thereto, as long as the slip ring 113 can be stably held on the cover member 120.

[0039] Furthermore, the bolt holes 120a are provided in a protruding portion 120aa that protrudes from the axially one - side - facing surface on the axially one - side of the cover member 120. With such a configuration, the cover member 120 can hold the slip ring 113 separately in the axial direction, and the degree of freedom in the shape of the slip ring 113 can be improved.

[0040] In the present embodiment, the slip ring 113 is not directly held on the frame 130, but is held on the cover member 120. Thereby, the holding structure for holding the slip ring 113 does not need to avoid the position of the opening of the flow path 131 in the radial direction, and the degrees of freedom of the slip ring and the frame can be improved. Thereby, the size of the motor can be miniaturized and the weight can be reduced.

[0041] In addition, in the present embodiment, the opening of the flow path 131 in the frame 130 can be blocked by the cover member 120 instead of the bracket. Therefore, the radial position of the flow path 131 can be determined regardless of the shape of the slip ring 113. Therefore, the flow path 131 can be arranged on the inner diameter side of the frame 130, that is, on the side closer to the stator core 111, the cooling efficiency can be improved, and miniaturization and weight reduction of the motor can be achieved.

[0042] The present invention is not limited to the above - described embodiment, and various improvements and design changes can be made without departing from the gist of the present invention. In addition, it should be considered that the embodiments disclosed this time are illustrative in all aspects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include all changes within the meaning and scope equivalent to the claims.

[0043] This application claims priority based on Japanese Patent Application No. 2023 - 005342 filed on January 17, 2023, and incorporates by reference all the contents described in the Japanese patent application.

[0044] Description of Reference Numerals

[0045] 100... stator structure, 110... stator, 120... cover member, 113... slip ring, 130... frame.

Claims

1. A stator structure, characterized in that, Comprising: A stator having a stator core and a stator coil wound around the stator core; A slip ring having a bus bar connected to the stator coil; A frame that radially inwardly houses the stator core and has a flow path for a refrigerant liquid that opens at one axial end and extends to the other axial side; A cover member that is disposed on the one axial side of the frame and on the other axial side of the slip ring and closes the opening of the flow path; and A holding structure that holds the slip ring to the cover member.

2. The stator structure according to claim 1, wherein: The holding structure fixes the cover member and the slip ring with bolts.

3. The stator structure according to claim 1, characterized in that, Comprising: A rotor that is disposed radially inward of the stator core; and An inverter unit that is disposed on the one axial side of the stator structure and drives the rotating electric machine.

4. The rotating electric machine according to claim 3, wherein: The rotating electric machine is used for driving an automobile.

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