Stator structure and rotary electric machine

Abstract

The present application aims to improve the freedom of a slip ring and a frame of a rotary electric machine. A stator structure 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 housing the stator core on the inner side in the radial direction and having a flow path of refrigerant liquid that is open at one side in the axial direction and extends to the other side in the axial direction; a cover member disposed on the one side in the axial direction of the frame and on the other side in the axial direction of the slip ring and blocking the opening of the flow path; and a holding structure holding the slip ring to the cover member.

Description

TECHNICAL FIELD

[0001] The present application relates to a stator configuration and a rotary electric machine. BACKGROUND

[0002] For example, in a three-phase alternating-current motor, a configuration is known in which the stator coils of each phase wound around a stator core are connected through a bus bar for each phase, and the bus bar for each phase is collected with a collector ring (for example, Patent Literature 1). The bus bar is a ring-shaped conductor.

[0003] In addition, as a cooling configuration of a motor, a configuration is known in which a flow path is provided in a frame that covers the outer periphery of a stator, and a refrigerant liquid such as water is caused to flow in the flow path to cool the stator and the like (for example, Patent Literature 2).

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

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

[0007] Patent Literature 2: International Publication No. 2013 / 069321 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] The frame of the motor is manufactured using a mold such as aluminum die casting. In this case, in order to form a flow path in the frame, it is necessary to make the flow path into a shape that is open to the outside of the frame for the purpose of demolding. In order to cool the stator over the entire axial direction, it is necessary to extend the flow path along the axial direction, and in this case, the opening for demolding is disposed at the axial end of the frame.

[0010] In addition, in the case of a motor for automobile driving and the like, in order to prevent breakage of the collector ring due to vibration and the like, it is preferable to hold the collector ring at a holding point. The collector ring is disposed at the axial end of the stator, and therefore it is considered to provide the holding point of the collector 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 disposed avoiding the opening. In this way, the degrees of freedom of the collector ring and the frame are low, and there is a problem such as becoming an obstacle to size reduction.

[0011] An object of the present application is to improve the degrees of freedom of the collector ring and the frame of a rotary electric machine.

[0012] MEANS FOR SOLVING THE PROBLEMS

[0013] One aspect of the stator structure of the present invention comprises: a stator having a stator core and a stator coil wound around the stator core; a slip ring having a busbar connected to the stator coil; a frame receiving the stator core radially inward and having a flow path for a refrigerant liquid that is open at one end in the axial direction and extends to the other side in the axial direction; a cover member disposed on one side of the frame and the other side in the axial direction of the slip ring, and sealing the opening of the flow path; and a retaining structure holding the slip ring to the cover member.

[0014] In one of the stator configurations described above, the retaining structure secures the cover member and the slip ring with bolts.

[0015] One aspect of the present invention provides a rotary motor comprising: the stator structure described above; a rotor disposed radially inside the stator core; and an inverter unit disposed on one axial side of the stator structure, for driving the rotary motor.

[0016] One of the aforementioned rotary motors is used to drive a car.

[0017] Invention Effects

[0018] According to one aspect of the present invention, the degrees of freedom of the slip ring and frame of the rotating electric motor can be improved. Attached Figure Description

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

[0020] Figure 2 It means to Figure 1 A side sectional view of the stator structure 100 after assembly.

[0021] Figure 3 It means Figure 1 A perspective view of the cover component 120. Detailed Implementation

[0022] Hereinafter, the stator structure according to an embodiment of the present invention will be described with reference to the accompanying drawings. Furthermore, in the following drawings, for ease of understanding of each structure, the actual structure and the scale and quantities in each structure may sometimes differ. Additionally, for ease of observation of each structure, it is shown in a schematic form that differs from the actual shape.

[0023] Furthermore, in the accompanying diagram, the XYZ coordinate system is appropriately represented as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the X-axis direction is perpendicular to the x-axis. Figure 1 The direction parallel to the axial direction of the central axis J is shown. The Y-axis direction is radially relative to the central axis J. Figure 1The Z-axis is the vertical direction. It is orthogonal to both the X-axis and Y-axis. In any of the X-axis, Y-axis, and Z-axis directions, the side indicated by the arrow in the diagram is the "+" side, and the opposite side is the "-" side.

[0024] In the following explanation, the negative side (-X side) of the X-axis direction will be referred to as "one side," and the positive side (+X side) of the X-axis direction will be referred to as "the other side." Furthermore, "one side" and "the other side" are merely illustrative terms and do not define the actual positional relationship or direction. Unless otherwise specified, the direction parallel to the central axis J (X-axis direction) will be simply referred to as "axial direction," the radial direction centered on the central axis J will be simply referred to as "radial direction," and the circumferential direction centered on the central axis J, i.e., the direction around the central axis J, will be simply referred to as "circumferential direction." The side radially closer to the central axis J will be referred to as "radial inner side," and the side farther from the central axis J will be referred to as "radial outer side."

[0025] Furthermore, in this specification, "extending axially" includes not only the case of extending strictly along the axial direction (X-axis direction), but also the case of extending in a direction inclined relative to the axial direction within a range of less than 45°. Additionally, in this specification, "extending radially" includes not only the case of extending strictly in a radial direction, i.e., perpendicular to the axial direction (X-axis direction), but also the case of extending in a direction inclined relative to the radial direction within a range of less than 45°. Furthermore, "parallel" includes not only the case of being strictly parallel, but also the case of being inclined at an angle of less than 45° between them.

[0026] <First Implementation Method>

[0027] Figure 1 This is an exploded perspective view showing a schematic stator structure according to a first embodiment of the present invention. The stator structure 100 forms the stator surrounding a motor, which is an example of a rotating electrical machine. The stator structure 100, for example, forms a three-phase AC motor. The stator structure 100 is configured to include a stator 110, a cover member 120, a frame 130, slip rings 113, and terminal blocks 114. The motor having the stator structure 100 has a rotor disposed radially inside the stator 110, but the rotor is not shown in the figure.

[0028] The stator 110 has a cylindrical stator core 111 and stator coils 112 wound around the stator core 111 for each phase. Slip rings 113 have a busbar 113a for each phase. The end of each phase's stator coil 112 is electrically connected to the busbar 113a of that phase. The outer diameter of the slip rings 113 is larger than the outer diameter of the stator core 111. The outer peripheral end of the slip rings 113 is located radially outward from the outer peripheral end of the stator core 111.

[0029] Terminal block 114 holds the respective terminals 113b of each phase busbar 113a, allowing for easy connection to external components. An inverter section for driving the motor is disposed on one axial side of the motor having stator structure 100, and each terminal of terminal block 114 is electrically connected to this inverter section. The motor having stator structure 100 is used, for example, for driving automobiles.

[0030] The frame 130 is cylindrical and houses the stator core 111 radially inward. The frame 130 and the stator core 111 are fixed, for example, by thermoforming. The frame 130 has a flow path 131, which serves as a flow path for a refrigerant liquid, such as water. The flow path 131 opens at one axial end of the frame 130 and extends from that opening to the other axial end. The frame 130 is manufactured using a mold, for example, like aluminum die casting. The opening at one axial end of the frame 130 via the flow path 131 allows for demolding of the shape of the flow path 131 during frame 130 manufacturing.

[0031] The cover member 120 is a component that seals the opening at one axial end of the frame 130 to prevent refrigerant liquid from leaking out when the refrigerant liquid flows in the flow path 131. The cover member 120 is disposed on one axial side of the frame 130 and the other axial side of the slip ring 113. The cover member 120 is an annular component and seals the opening when fixed to one axial end of the frame 130 by having a surface facing the opening at 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 allowing refrigerant liquid to flow in the flow path 131. The refrigerant liquid in the flow path 131 is circulated, for example, by a pump or the like, through an inlet and an outlet provided on the side of the frame 130.

[0032] The stator structure 100 has bolts 120c. The cover member 120 has bolt holes 120b for inserting bolts 120c. The frame 130 has bolt holes 130a for inserting bolts 120c. Bolts 120c fix and hold the cover member 120 to the frame 130 such that the face of the cover member 120 on the other side of its axial direction is engaged with the face of the frame 130 on one side of its axial direction. Bolts 120c, bolt holes 120b, and bolt holes 130a are an example of a holding structure for holding the cover member 120 to the frame 130. Multiple bolts 120c, bolt holes 120b, and bolt holes 130a are provided in the circumferential direction.

[0033] The stator structure 100 has a bolt 113d. The slip ring 113 has a bolt hole 113c for inserting the bolt 113d. The cover member 120 has a bolt hole 120a for inserting the bolt 113d. The bolt 113d secures and holds the slip ring 113 to the cover member 120 such that the face of the slip ring 113 on the other axial side is engaged with the face of the cover member 120 on one axial side. The bolt 113, bolt hole 113c, and bolt hole 120a are examples of a holding structure for holding the slip ring 113 to the cover member 120. Multiple bolts 113, bolt holes 113c, and bolt holes 120a are provided circumferentially.

[0034] The stator structure 100 has bolts 114a. The cover member 120 has bolt holes 120d for inserting bolts 114a. The terminal block 114 is fixed to the cover member 120 by bolts 114a. Bolts 114a and bolt holes 120d are provided on both circumferential sides of the terminal block 114.

[0035] Figure 2 It means to Figure 1 A side sectional view of the stator structure 100 after assembly. Figure 2 It is shown by sectioning through a plane passing through the central axis J and orthogonal to the Z-axis. The axial side of the stator core 112 may also be covered by a bracket from the axial side and radially outward. The bracket is bolted to the frame 130 or the cover member 120 at a location different from the bolt fixing position of the frame 130 and the cover member 120.

[0036] A slip ring 113 is disposed radially outward of the coil end on one axial side of the stator coil 112. At least a portion of the slip ring 113 overlaps axially with the cover member 120. At least a portion of the cover member 120 overlaps axially with the frame 130. Furthermore, the radial length on the other axial side of the flow path 131 is shorter than the radial length on the axial side. This shape facilitates smooth demolding of the flow path 131 during the manufacture of the frame 130.

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

[0038] Furthermore, in this embodiment, three bolt holes 120a are arranged circumferentially in the cover member 120. That is, a combination of three bolts 113d, bolt holes 113c, and bolt holes 120a is arranged circumferentially. The number of bolts 113d, bolt holes 113c, and bolt holes 120a is not limited to this, as long as the slip ring 113 can be stably held in the cover member 120.

[0039] Furthermore, bolt holes 120a are provided in the protrusion 120aa that protrudes from the axial side of the cover member 120. With this configuration, the cover member 120 can hold the slip ring 113 separately in the axial direction, which can improve the degree of freedom in the shape of the slip ring 113.

[0040] In this embodiment, the slip ring 113 is not held directly to the frame 130, but rather to the cover member 120. Therefore, the holding structure of the slip ring 113 does not need to avoid the opening of the flow path 131 in the radial direction, improving the freedom of movement of the slip ring and the frame. This allows for miniaturization of the motor and reduction of its weight.

[0041] Furthermore, in this embodiment, the opening of the flow path 131 in the frame 130 can be sealed by the cover member 120 instead of by the bracket, so the radial position of the flow path 131 can be determined independently of the shape of the slip ring 113. Therefore, by arranging the flow path 131 on the inner diameter side of the frame 130, i.e., the side close to the stator core 111, cooling efficiency can be improved, and miniaturization and weight reduction of the motor can be achieved.

[0042] This invention is not limited to the embodiments described above. Various modifications and design changes can be made without departing from the spirit of the invention. Furthermore, the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of this invention is not shown by the foregoing description but by the claims, and is intended to include all modifications 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 invokes all the contents described in that Japanese Patent Application.

[0044] Explanation of reference numerals in the attached figures

[0045] 100…Stator structure, 110…Stator, 120…Cover component, 113…Collector ring, 130…Frame.

Claims

1. A stator construction, characterized by Possessing: a stator having a stator core and a stator coil wound on the stator core; a current collector ring having a bus bar connected to the stator coil; a frame housing the stator core on the radially inner side and having a flow path of refrigerant liquid opened on one axial side and extending to the other axial side; a cover member disposed on the one axial side of the frame and the other axial side of the current collector ring and closing the opening of the flow path; and a holding structure holding the current collector ring to the cover member.

2. The stator structure according to claim 1, characterized in that the holding structure fixes the cover member and the current collector ring by a bolt.

3. A rotary electric machine characterized by Possessing: the stator structure according to claim 1; a rotor disposed on the radially inner side of the stator core; and an inverter section disposed on the one axial side of the stator structure and driving the rotary electric machine.

4. The rotary electric machine according to claim 3, characterized in that the rotary electric machine is used for driving of an automobile.

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