rotor

Abstract

To stably fix a slip ring structure to a shaft.SOLUTION: A slip ring structure 6 includes two conductive rings 11 arranged on an outer periphery of a shaft 5, two bus bars 12 extending from two conductive rings 11 respectively in order to electrically connect two conductive rings 11 to windings 3a of a plurality of coils 3, and a resin molding 13 holding two conductive rings 11 and two bus bars 12 by insert molding. The resin molding 13 has a molding body 20 holding two conductive rings 11, an annular terminal holding part 21 holding a terminal part 12c of two bus bars 12, and two connection parts 22 connecting the molding body 20 and the terminal holding part 21. The terminal holding part 21 is held in a sealing resin 4, thereby the slip ring structure 6 is fixed to the shaft 5.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a rotor.

Background Art

[0002] Patent Document 1 discloses a technique for, in a slip ring device included in a rotor of a rotating electric machine, holding two rings by insert molding and preventing cracking at a weld line of a resin molded body main body into which a shaft of the rotor is press-fitted.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] In the slip ring device of the above-mentioned Patent Document 1, it is known that due to the difference in thermal expansion coefficient between resin and metal, the interference decreases at high temperatures and increases at low temperatures.

[0005] In the above-mentioned Patent Document 1, the interference during assembly is increased to leave interference even at high temperatures. However, conversely, the interference increases at low temperatures, so the stress generated in the molded body main body increases. Therefore, in the above-mentioned Patent Document 1, even if resin cracking during assembly can be prevented, there is a concern that the interference increases at low temperatures and resin cracking occurs.

[0006] Here, there is a trade-off relationship between maintaining residual interference even at high temperatures and preventing resin cracking even when the interference increases at low temperatures. Therefore, to achieve both of these, strict dimensional control that is completely unrealistic will be required for the inner diameter of the molded body main body and the outer diameter of the shaft.

[0007] The purpose of this disclosure is to provide a technology for stably fixing a slip ring structure to a shaft. [Means for solving the problem]

[0008] A rotor for a rotating electric machine is provided, comprising a core, a plurality of coils provided on the core, a sealing resin that seals the plurality of coils, a shaft fixed to the core, and a slip ring structure that rotates with the shaft, wherein the slip ring structure comprises two conductive rings arranged on the outer circumference of the shaft, two busbars extending from the two conductive rings to electrically connect the two conductive rings to the windings of the plurality of coils, and a resin molded body that holds the two conductive rings and the two busbars by insert molding, wherein the resin molded body has a molded body body that holds the two conductive rings, an annular terminal holding portion that holds the terminal portions of the two busbars, and at least one connecting portion that connects the molded body body and the terminal holding portion, the terminal holding portion being held in the sealing resin, thereby fixing the slip ring structure to the shaft. With the above configuration, the slip ring structure can be stably fixed to the shaft. Furthermore, the terminal holding portion comprises a cylindrical holding portion body and a projection that protrudes radially outward from the outer circumferential surface of the holding portion body, and the projection may be sealed by the sealing resin. With the above configuration, the slip ring structure can be stably fixed to the shaft in both the axial and circumferential directions of the shaft. Furthermore, the terminal holding portion comprises a holding portion body and a flange protruding radially outward from the outer circumferential surface of the holding portion body, and the flange may be sealed by the sealing resin. With the above configuration, the slip ring structure can be stably fixed to the shaft in the axial direction of the shaft. Furthermore, the outer circumferential surface of the terminal holding portion may be formed in an uneven manner when viewed from the axial direction of the shaft, and the outer circumferential surface of the terminal holding portion may be sealed with the sealing resin. With the above configuration, the slip ring structure can be stably fixed to the shaft in the circumferential direction of the shaft. Furthermore, the terminal holding portion comprises a holding portion body and a flange protruding radially outward from the outer circumferential surface of the holding portion body, wherein the outer circumferential surface of the flange is formed in an uneven manner when viewed from the axial direction of the shaft, and the outer circumferential surface of the flange may be sealed with the sealing resin. With the above configuration, the slip ring structure can be stably fixed to the shaft in the circumferential direction of the shaft. [Effects of the Invention]

[0009] According to this disclosure, the slip ring structure can be stably fixed to the shaft. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view of the rotor. [Figure 2] This is an exploded perspective view of the rotor. [Figure 3] This is an enlarged view of section A in Figure 2. [Figure 4] This is a cross-sectional view of the rotor. [Modes for carrying out the invention]

[0011] The present invention will be described below through embodiments of the invention, but the invention claimed is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential as means of solving the problem. For clarity of explanation, the following descriptions and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are denoted by the same reference numerals, and redundant explanations have been omitted where necessary.

[0012] FIG. 1 is a perspective view of a rotor 1. The rotor 1 typically constitutes a wound-field motor. The motor includes a stator (not shown) to which an armature current is supplied, and the rotor 1 to which a field current is supplied.

[0013] As shown in FIG. 1, the rotor 1 includes a core 2, a plurality of coils 3, a sealing resin 4, a shaft 5, and a slip ring structure 6.

[0014] FIG. 2 shows an exploded perspective view of the rotor 1. FIG. 3 shows an enlarged view of part A in FIG. 2. FIG. 4 shows a cross-sectional view of the rotor 1. For convenience of explanation, only the shaft 5 and the slip ring structure 6 are shown in FIG. 2.

[0015] Referring to FIG. 1, the core 2 is typically configured by laminating a plurality of electromagnetic steel sheets. The core 2 has a plurality of teeth 7.

[0016] The plurality of coils 3 are respectively provided on the plurality of teeth 7 of the core 2. Each coil 3 is constituted by a winding 3a. The winding 3a is typically a round wire.

[0017] As shown in FIG. 4, the sealing resin 4 seals the plurality of coils 3. The sealing resin 4 is typically an epoxy resin. For convenience of explanation, hatching of the sealing resin 4 is omitted in FIG. 4.

[0018] Returning to FIG. 1, the core 2 is fixed to the shaft 5. As shown in FIG. 2, the shaft 5 includes a shaft body 8 penetrating the core 2, and a shaft distal end portion 9 having a smaller diameter than the shaft body 8. Two busbar accommodation grooves 10 are formed in the shaft body 8. The two busbar accommodation grooves 10 are formed on opposite sides to each other across the central axis 5C of the shaft 5.

[0019] The slip ring structure 6 is configured to rotate together with the shaft 5 while being fixed to the shaft 5. The slip ring structure 6 includes two conductive rings 11, two busbars 12, and a resin molded body 13.

[0020] As shown in Figure 4, the two conductive rings (11) are arranged on the outer circumference of the shaft tip (9) of the shaft (5). The two conductive rings (11) are arranged spaced apart from each other in the axial direction of the shaft (5). The two conductive rings (11) are exposed radially outward. Here, radially outward means outward in the radial direction of the shaft (5). Conversely, radially inward means inward in the radial direction of the shaft (5).

[0021] The two bus bars (12) respectively electrically connect the two conductive rings (11) to the windings (3a) constituting the plurality of coils (3). The two bus bars (12) are each electrically connected to the two conductive rings (11) respectively. The two bus bars (12) each extend from the two conductive rings (11) along the axial direction of the shaft (5), and then extend radially outward. Accordingly, when observed from a direction orthogonal to the axial direction of the shaft (5), each of the two bus bars (12) extends in a substantially L-shape. Here, the front and the rear are defined. Both the front and the rear are directions parallel to the axial direction of the shaft (5). The front is the direction from which the two conductive rings (11) are viewed from the plurality of coils (3). The rear is the direction from which the plurality of coils (3) are viewed from the two conductive rings (11). Each bus bar (12) includes a front bus bar (12a) extending rearward from the corresponding conductive ring (11), and a rear bus bar (12b) extending radially outward from the rear end of the front bus bar (12a). A terminal portion (12c) to which the winding (3a) is crimped or soldered is formed at the tip of the rear bus bar (12b) of each bus bar (12).

[0022] Returning to Figure 2, the resin molded body (13) holds the two conductive rings (11) and the two bus bars (12) by insert molding. Specifically, the resin molded body (13) includes a molded body main body (20), a terminal holding portion (21), and two connecting portions (22). The molded body main body (20), the two connecting portions (22), and the terminal holding portion (21) are arranged in this order toward the rear.

[0023] The molded body 20 is cylindrical and holds two conductive rings 11. The molded body 20 is lightly press-fitted onto the shaft tip 9 of the shaft 5. However, the molded body 20 does not necessarily have to be press-fitted onto the shaft tip 9 of the shaft 5.

[0024] The terminal holding portion 21 is annular in shape and holds the terminal portions 12c of the two busbars 12. However, the terminal holding portion 21 does not have to be annular in shape.

[0025] The two connecting portions 22 are formed to connect the molded body 20 and the terminal holding portion 21. The two connecting portions 22 are formed in an L-shape so as to cover the two busbars 12 respectively.

[0026] The terminal holding portion 21 will be described in detail below with reference to Figures 2 to 4.

[0027] As shown in Figure 2, the terminal holding portion 21 includes a cylindrical holding portion body 30, an uneven projection portion 31 projecting radially outward from the outer circumferential surface 30a of the holding portion body 30, and a flange 32 projecting radially outward from the outer circumferential surface 30a of the holding portion body 30. The uneven projection portion 31 is one specific example of the projection portion. However, the holding portion body 30 does not have to be cylindrical.

[0028] The terminal portions 12c of the two busbars 12 are exposed so as to protrude radially outward from the outer circumferential surface 30a of the holding body 30.

[0029] The uneven protrusion 31 is positioned behind the terminal portions 12c of the two busbars 12. The uneven protrusion 31 is formed in a thin plate shape perpendicular to the axial direction of the shaft 5. As shown in Figure 3, the uneven protrusion 31 includes a first protrusion 31a and a second protrusion 31b, which are at different distances from the central axis 5C of the shaft 5. For example, the second protrusion 31b protrudes radially outward more than the first protrusion 31a. Therefore, it can be said that the uneven protrusion 31 has an uneven outer surface 31P when viewed along the axial direction of the shaft 5. The uneven protrusion 31 has a front surface 31F facing forward and a rear surface 31R facing backward.

[0030] The flange 32 is positioned behind the uneven projection 31. The flange 32 is formed in a thin plate shape perpendicular to the axial direction of the shaft 5. The flange 32 includes a first flange portion 32a and a second flange portion 32b, which are at different distances from the central axis 5C of the shaft 5. For example, the first flange portion 32a protrudes radially outward more than the second flange portion 32b. Therefore, the flange 32 can be said to have an uneven outer surface 32P when viewed along the axial direction of the shaft 5. The flange 32 has a front surface 32F facing forward and a rear surface 32R facing backward.

[0031] As shown in Figure 4, the terminal holding portion 21 is held by the sealing resin 4. This ensures that the slip ring structure 6 is stably fixed to the shaft 5. Specifically, it is as follows:

[0032] The uneven protrusions 31 are sealed by the sealing resin 4. Specifically, the front surface 31F and rear surface 31R of the uneven protrusions 31 are covered with the sealing resin 4. Therefore, the movement of the slip ring structure 6 in the front-rear direction relative to the shaft 5 is restricted, and the slip ring structure 6 is stably fixed in the front-rear direction by the shaft 5. In addition, both the first protrusion 31a and the second protrusion 31b of the uneven protrusions 31 are sealed by the sealing resin 4, and the outer peripheral surface 31P of the uneven protrusions 31 is sealed by the sealing resin 4. Therefore, the rotation of the slip ring structure 6 relative to the shaft 5 is restricted, and the slip ring structure 6 is stably fixed in the circumferential direction by the shaft 5.

[0033] The flange 32 is sealed with sealing resin 4. Specifically, the front surface 32F and rear surface 32R of the flange 32 are covered with sealing resin 4. Therefore, the movement of the slip ring structure 6 in the front-rear direction relative to the shaft 5 is restricted, and the slip ring structure 6 is stably fixed in the front-rear direction by the shaft 5. In addition, both the first flange portion 32a and the second flange portion 32b of the flange 32 are sealed with sealing resin 4, and the outer peripheral surface 32P of the flange 32 is sealed with sealing resin 4. Therefore, the rotation of the slip ring structure 6 relative to the shaft 5 is restricted, and the slip ring structure 6 is stably fixed in the circumferential direction by the shaft 5.

[0034] In this way, the uneven protrusions 31 and the flange 32 are designed to independently perform the functions of stably fixing the slip ring structure 6 circumferentially by the shaft 5 and stably fixing the slip ring structure 6 axially by the shaft 5.

[0035] As shown in Figure 2, the two connecting portions 22 of the slip ring structure 6 are inserted into the two busbar accommodating grooves 10 of the shaft 5. This also restricts the rotation of the slip ring structure 6 relative to the shaft 5.

[0036] Preferred embodiments of the present disclosure have been described above. The above embodiments have the following features.

[0037] The rotor 1 includes a core 2, a plurality of coils 3 provided on the core 2, a sealing resin 4 that seals the plurality of coils 3, a shaft 5 fixed to the core 2, and a slip ring structure 6 that rotates with the shaft 5. The slip ring structure 6 includes two conductive rings 11 arranged on the outer circumference of the shaft 5, two busbars 12 extending from the two conductive rings 11 to electrically connect the two conductive rings 11 to the windings 3a of the plurality of coils 3, and a resin molded body 13 that holds the two conductive rings 11 and the two busbars 12 by insert molding. The resin molded body 13 has a molded body body 20 that holds the two conductive rings 11, an annular terminal holding portion 21 that holds the terminal portions 12c of the two busbars 12, and two connecting portions 22 that connect the molded body body 20 and the terminal holding portion 21. The terminal holding portion 21 is held by the sealing resin 4, thereby fixing the slip ring structure 6 to the shaft 5. With the above configuration, the slip ring structure 6 can be stably fixed to the shaft 5 without relying on the overlap between the molded body 20 and the shaft tip 9 of the shaft 5.

[0038] In the above embodiment, the resin molded body 13 has two connecting parts 22. However, instead, the resin molded body 13 may have only one connecting part 22, or it may have three or more connecting parts 22.

[0039] Furthermore, the terminal holding portion 21 has a cylindrical holding portion body 30 and an uneven protrusion portion 31 (protrusion portion) that protrudes radially outward from the outer peripheral surface 30a of the holding portion body 30. The uneven protrusion portion 31 is sealed by a sealing resin 4. With the above configuration, the slip ring structure 6 can be stably fixed to the shaft 5 in both the axial and circumferential directions of the shaft 5.

[0040] Furthermore, the terminal holding portion 21 has a cylindrical holding portion body 30 and a flange 32 that protrudes radially outward in an annular shape from the outer peripheral surface 30a of the holding portion body 30. The flange 32 is sealed with a sealing resin 4. With the above configuration, the slip ring structure 6 can be stably fixed to the shaft 5 in the axial direction of the shaft 5.

[0041] Furthermore, when viewed from the axial direction of the shaft 5, the outer circumferential surface 31P of the uneven protrusion 31 of the terminal holding portion 21 is formed in an uneven shape, and the outer circumferential surface 31P of the uneven protrusion 31 of the terminal holding portion 21 is sealed by the sealing resin 4. With the above configuration, the slip ring structure 6 can be stably fixed to the shaft 5 in the circumferential direction of the shaft 5. The outer circumferential surface 31P of the uneven protrusion 31 constitutes a part of the outer circumferential surface of the terminal holding portion 21.

[0042] Furthermore, the terminal holding portion 21 includes a cylindrical holding portion body 30 and a flange 32 that protrudes radially outward in an annular shape from the outer peripheral surface 30a of the holding portion body 30. When viewed from the axial direction of the shaft 5, the outer peripheral surface 32P of the flange 32 is formed in an uneven manner, and the outer peripheral surface 32P of the flange 32 is sealed with a sealing resin 4. With the above configuration, the slip ring structure 6 can be stably fixed to the shaft 5 in the circumferential direction of the shaft 5. [Explanation of Symbols]

[0043] 1 Rotor 2 cores 3 coils 3a winding 4 Sealing resin 5 shafts 5C center axis 6. Slip ring structure 7 Teeth 8. Shaft body 9. Shaft tip 10 Busbar housing grooves 11 Conductive ring 12 bus bars 12a Front busbar 12b Rear busbar 12c terminal section 13 Resin molded body 20 Molded body 21 Terminal holding part 22 Connecting part 30 Holding unit body 30a Outer surface 31. Concave and convex parts 31a First protrusion 31b Second protrusion 31P outer periphery 31F Front 31R after 32 フランジ 32a Part 1 Furucon 32b Part 2 Furacon 32P outer periphery 32F Front 32R after

Claims

1. A core and Multiple coils provided in the core, A sealing resin for sealing the plurality of coils, A shaft fixed to the core, A slip ring structure that rotates together with the shaft, Includes, The aforementioned slip ring structure is Two conductive rings are arranged on the outer circumference of the shaft, To electrically connect the two conductive rings to the windings of the plurality of coils, two busbars extend from each of the two conductive rings, A resin molded body that holds the two conductive rings and the two busbars by insert molding, Includes, The aforementioned resin molded body is A molded body that holds the two conductive rings, An annular terminal holding portion that holds the terminal portions of the two busbars, At least one connecting portion that connects the molded body and the terminal holding portion, It has, The terminal holding portion is held by the sealing resin, thereby fixing the slip ring structure to the shaft. The terminal holding portion comprises a holding portion body and a flange that protrudes radially outward from the outer circumferential surface of the holding portion body. The flange is sealed by the sealing resin. Rotor.

2. A core and, Multiple coils provided in the core, A sealing resin for sealing the plurality of coils, A shaft fixed to the core, A slip ring structure that rotates together with the shaft, Includes, The aforementioned slip ring structure is Two conductive rings are arranged on the outer circumference of the shaft, To electrically connect the two conductive rings to the windings of the plurality of coils, two busbars extend from each of the two conductive rings, A resin molded body that holds the two conductive rings and the two busbars by insert molding, Includes, The aforementioned resin molded body is A molded body that holds the two conductive rings, An annular terminal holding portion that holds the terminal portions of the two busbars, At least one connecting portion that connects the molded body and the terminal holding portion, It has, The terminal holding portion is held by the sealing resin, thereby fixing the slip ring structure to the shaft. When viewed from the axial direction of the shaft, the outer circumferential surface of the terminal holding portion is formed in an uneven manner, and the outer circumferential surface of the terminal holding portion is sealed by the sealing resin. Rotor.

3. A core and Multiple coils provided in the core, A sealing resin for sealing the plurality of coils, A shaft fixed to the core, A slip ring structure that rotates together with the shaft, Includes, The aforementioned slip ring structure is Two conductive rings are arranged on the outer circumference of the shaft, To electrically connect the two conductive rings to the windings of the plurality of coils, two busbars extend from each of the two conductive rings, A resin molded body that holds the two conductive rings and the two busbars by insert molding, Includes, The aforementioned resin molded body is A molded body that holds the two conductive rings, An annular terminal holding portion that holds the terminal portions of the two busbars, At least one connecting portion that connects the molded body and the terminal holding portion, It has, The terminal holding portion is held by the sealing resin, thereby fixing the slip ring structure to the shaft. The terminal holding portion comprises a holding portion body and a flange that protrudes radially outward from the outer circumferential surface of the holding portion body. The outer surface of the flange is formed in an uneven manner when viewed from the axial direction of the shaft, and the outer surface of the flange is sealed with the sealing resin. Rotor.

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