Stator, rotary electric machine, and work machine

Abstract

This stator comprises a stator coil that is wound around a cylindrical stator core, and has a plurality of terminal-side extension parts extending outward from a first end surface in the axial direction of the stator core and arranged side-by-side in the circumferential direction of the stator core. The plurality of terminal-side extension parts include a first extension part and a second extension part that can be bent between a portion connected to a power line and the first end surface, and that are adjacent to each other in the circumferential direction. The first extension part and the second extension part are bent at different positions in the axial direction.

Description

Stator, rotating electric machine and work machine

[0001] This disclosure claims priority to Japanese Patent Application No. 2023-223120, filed on December 28, 2023, the contents of which are incorporated herein by reference.

[0002] Conventionally, a configuration is known for a stator of a rotating electric machine, which includes a stator coil wound around a cylindrical stator core and having a plurality of end-side extension portions extending outward from a first axial end face of the stator core and aligned circumferentially around the stator core (see Patent Document 1).

[0003] International Publication No. 2017 / 168971

[0004] However, the configuration of Patent Document 1 may result in poor assembly when connecting the power lines, an increase in the number of parts, and an increase in size, depending on the position at which the power lines are connected and the position at which the coil is bent.

[0005] An object of aspects of the present disclosure is to provide a stator, a rotating electric machine, and a work machine that can improve assembly efficiency, reduce the number of parts, and achieve miniaturization.

[0006] A stator according to one aspect of the present disclosure comprises a stator coil wound around a cylindrical stator core, extending outward from a first axial end face of the stator core and having a plurality of end-side extension portions aligned circumferentially around the stator core, the plurality of end-side extension portions including a first extension portion and a second extension portion that are bent between a point where a power line is connected and the first end face and are adjacent to each other in the circumferential direction, and the bending positions of the first extension portion and the second extension portion are different from each other in the axial direction.

[0007] According to aspects of the present disclosure, it is possible to provide a stator, a rotating electric machine, and a work machine that can improve assembly efficiency, reduce the number of parts, and achieve miniaturization.

[0008] Fig. 1 is a schematic diagram showing a work machine according to an embodiment; Fig. 2 is a cross-sectional view of a rotating electric machine according to an embodiment; Fig. 3 is a perspective view of a stator according to an embodiment; Fig. 4 is a perspective view of an inner circumferential portion of a stator according to an embodiment; Fig. 5 is a perspective view showing the distance from a reference position to the bending position of each of a first extension portion and a second extension portion according to an embodiment; Fig. 6 is a diagram showing the bending position of a coil according to a comparative example;

[0009] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In this embodiment, an example will be described in which a rotating electric machine is mounted on an electric rotary shovel (an example of a work machine) and configured as a swing motor for swinging an upper swing body of the electric rotary shovel.

[0010] In the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," do not only mean such arrangements or states in the strict sense, but also include arrangements or states in which there is a relative displacement with a tolerance or an angle or distance to the extent that the same function is obtained. In the drawings used in the following description, the scale of each component may be changed as appropriate to make each component recognizable.

[0011] <Construction machine> Figure 1 is a schematic diagram showing a construction machine according to an embodiment. The construction machine 100 according to this embodiment is an electric hydraulic excavator. The construction machine 100 may be a manned vehicle that is operated by a driver, or an unmanned vehicle that is operated without a driver.

[0012] The work machine 100 includes a running body 120 , an upper rotating body 140 , and a work implement 160 .

[0013] The running body 120 supports the work machine 100 so that it can travel. The running body 120 is equipped with running devices 121. The running devices 121 are, for example, a pair of left and right caterpillars. The running devices 121 are driven by a traveling motor 122. The upper rotating body 140 is supported on the running body 120 so that it can rotate about a rotation axis. The upper rotating body 140 rotates relative to the running body 120 by the rotation motor 114. The upper rotating body 140 has a compartment 141 that houses a drive system.

[0014] The work implement 160 is operably supported on the upper rotating body 140. The work implement 160 is hydraulically driven. The work implement 160 includes a boom 161, an arm 162, and an attachment 163. The attachment 163 is an example of a working tool. In the example shown in FIG. 1, the attachment 163 is a bucket. In the example shown in FIG. 1, the side of the upper rotating body 140 on which the work implement 160 is supported is the front, and the opposite side with respect to the front is the rear. In this embodiment, the left-right direction refers to the left and right relative to the front, and the up-down direction refers to the direction in which the rotation axis of the upper rotating body 140 extends.

[0015] The swing motor 114 is an electric motor (an example of a rotating electric machine) that is driven by electricity. The swing motor 114 swings the upper swing body 140 relative to the traveling body 120.

[0016] <Rotating Electric Machine> FIG. 2 is a cross-sectional view of the rotating electric machine 1 according to the embodiment.

[0017] In this embodiment, the rotating electric machine 1 is a swing motor 114. The rotating electric machine 1 includes a rotor 2, a stator 3, and a housing 4 that accommodates the rotor 2 and the stator 3. The rotating electric machine 1 is an inner rotor type motor in which the stator 3 is disposed outside the cylindrical rotor 2. The rotating electric machine 1 is placed vertically so that the rotor shaft 20 of the rotor 2 is parallel to the swing axis.

[0018] In this embodiment, the upper side corresponds to one side parallel to the central axis CL of the rotor shaft 20, and the lower side corresponds to the other side parallel to the central axis CL of the rotor shaft 20. Hereinafter, the direction along the central axis CL of the rotor shaft 20 will be referred to as the "axial direction," the direction perpendicular to the axial direction will be referred to as the "radial direction," and the direction going around the central axis CL of the rotor shaft 20 will be referred to as the "circumferential direction."

[0019] The rotor 2 includes a rotor shaft 20, a rotor core 21, an upper plate 22, and a lower plate 23. The rotor shaft 20 is rotatably supported relative to the housing 4 by bearings 21A and 21B.

[0020] The rotor core 21 is formed by, for example, laminating electromagnetic steel sheets in the axial direction. The rotor core 21 is fitted onto the rotor shaft 20. The rotor core 21 rotates integrally with the rotor shaft 20. A plurality of permanent magnets (not shown) are embedded in the rotor core 21.

[0021] Each of the upper plate 22 and the lower plate 23 is annular plate members arranged coaxially with the rotor shaft 20. The upper plate 22 and the lower plate 23 are fitted to the rotor shaft 20. The upper plate 22 and the lower plate 23 sandwich the rotor core 21 from the outside in the axial direction. The upper plate 22 and the lower plate 23 rotate integrally with the rotor shaft 20 and the rotor core 21.

[0022] The stator 3 is fixed to the inner surface of the housing 4 so as to cover the outer periphery of the rotor 2. The stator 3 includes a cylindrical stator core 30 and a stator coil 31. Like the rotor core 21, the stator core 30 is formed by laminating electromagnetic steel sheets in the axial direction. A plurality of teeth are provided circumferentially on the inner periphery of the stator core 30. The stator coil 31 is wound around the teeth.

[0023] The housing 4 accommodates the rotor 2 and the stator 3. The housing 4 includes a cylindrical body 10, a ceiling portion 11 that closes the upper opening of the cylinder 10, and a bottom portion 13 that closes the lower opening of the cylinder 10. The cylinder 10, the ceiling portion 11, and the bottom portion 13 form a space 40 inside the housing 4 for accommodating the rotor 2 and the stator 3.

[0024] 3 is a perspective view of the stator 3 according to the embodiment. Referring to both Fig. 2 and Fig. 3, the stator 3 includes a cylindrical stator core 30 having a plurality of slots 30s arranged in a circumferential direction, and a stator coil 31 inserted into each of the plurality of slots 30s and wound around the stator core 30, the stator coil 31 having a plurality of end-side extending portions 32e extending outward from a first axial end face 30f1 of the stator core 30 and arranged in a circumferential direction.

[0025] A plurality of slots 30s and a plurality of teeth 30t are arranged alternately around the inner periphery of the stator core 30. The plurality of slots 30s are arranged at equal intervals in the circumferential direction of the stator core 30. For example, an insulating material may be provided inside the slots 30s. Note that the configuration of the slots 30s (such as their arrangement, number, and shape) can be changed according to design specifications.

[0026] In this embodiment, the stator coil 31 is made of rectangular wire. The stator coil 31 is made of multiple U-shaped segment coils 39 whose ends are connected to each other. The stator coil 31 is formed by winding multiple segment coils 39 whose ends are connected to each other in a wave-like pattern. For example, the segment coils 39 are rectangular wires with an insulating coating, in which an insulating coating is applied to the outer periphery of the wire. Note that the segment coils 39 are not limited to the above, and may also be made up of windings with circular or elliptical cross sections. The configuration of the segment coils 39 can be changed according to the design specifications.

[0027] The stator coil 31 includes a first coil end 32 having a plurality of distal extensions 32e protruding from a first axial end face 30f1 of the stator core 30, and a second coil end 33 protruding from a second end face 30f2 of the stator core 30 opposite the first end face 30f1 in the axial direction. The axial direction of the stator core 30 corresponds to the direction along the central axis CL (see FIG. 2 ) of the rotor shaft 20. The first end face 30f1 of the stator core 30 corresponds to the upper end face of the stator core 30. The second end face 30f2 of the stator core 30 corresponds to the lower end face of the stator core 30. Note that the radial direction of the stator core 30 is a direction perpendicular to the axial direction, and the circumferential direction is a direction going around the central axis CL.

[0028] In this embodiment, the first coil end 32 is arranged on the opposite side (upper side) of the bottom 13 of the housing 4 in the axial direction. On the other hand, the second coil end 33 is arranged on the same side (lower side) of the bottom 13 of the housing 4 in the axial direction. In this embodiment, the multiple distal extensions 32e are arranged on the opposite side (upper side) of the bottom 13 of the housing 4 in the axial direction.

[0029] FIG. 4 is a perspective view of the inner periphery of the stator 3 according to the embodiment. Referring to both FIGS. 3 and 4 , the stator 3 according to the embodiment further includes power lines 35U, 35V, and 35W connected to a plurality of distal extension portions 32e. The distal extension portions 32e include connection extension portions 32j to which the power lines 35U, 35V, and 35W are connected and non-connection extension portions 32u to which the power lines 35U, 35V, and 35W are not connected. The power lines 35U, 35V, and 35W include a stranded wire and terminals connected to the ends of the stranded wire. A connection member 38 for connecting the power lines 35U, 35V, and 35W is connected to the connection extension portion 32j. The connection member 38 is connected to the terminals of the power lines 35U, 35V, and 35W.

[0030] In this embodiment, the stator coil 31 includes three-phase winding groups 34U1, 34U2, 34V1, 34V2, 34W1, and 34W2 connected in parallel to one another. The three-phase winding groups 34U1, 34U2, 34V1, 34V2, 34W1, and 34W2 are winding groups for the U, V, and W phases. The U, V, and W-phase winding groups 34U1, 34U2, 34V1, 34V2, 34W1, and 34W2 are arranged two by two in the circumferential direction of the stator core 30, such as U phase, U phase, V phase, V phase, W phase, and so on.

[0031] <Bending Positions of the First and Second Extension Portions> Figure 5 is a perspective view showing the distances D1 and D2 from the reference position Pc to the bending positions P1 and P2 of the first and second extension portions 32j1 and 32j2 according to the embodiment. Referring to Figures 3 to 5, the distal extension portions 32e include the first extension portion 32j1 and the second extension portion 32j2 that are bent between the first end face 30f1 and the portions to which the power lines 35U, 35V, and 35W are connected and that are adjacent to each other in the circumferential direction. In the illustrated example, the first extension portion 32j1 and the second extension portion 32j2 constitute the connection extension portion 32j.

[0032] The bending positions P1 and P2 of the first extending portion 32j1 and the second extending portion 32j2 are different from each other in the axial direction. Note that the bending positions P1 and P2 refer to bending positions between the first end face 30f1 and the portions to which the power lines 35U, 35V, and 35W are connected, immediately before the portions to which the power lines 35U, 35V, and 35W are connected (excluding bending positions closer to the first end face 30f1).

[0033] In this embodiment, the bending position P1 of the first extending portion 32j1 is located axially outward (upper) from the reference position Pc. The reference position Pc refers to a normal bending position (corresponding to the bending position of the distal extending portion 32e of the non-connected extending portion 32u). The bending position P2 of the second extending portion 32j2 is located axially inward (lower) from the reference position Pc.

[0034] In this embodiment, the distances D1 and D2 from the reference position Pc to the bending positions P1 and P2 of the first extension portion 32j1 and the second extension portion 32j2 are the same, and refer to the distances (lengths) between the reference position Pc and the bending positions P1 and P2 in the axial direction.

[0035] The distance D1 from the reference position Pc to the bending position P1 of the first extending portion 32j1 may be set in the range of 1 / 2 to 2 times the distance D2 from the reference position Pc to the bending position P2 of the second extending portion 32j2. The distances D1 and D2 from the reference position Pc to the bending positions P1 and P2 of the first extending portion 32j1 and the second extending portion 32j2, respectively, may be changed according to design specifications.

[0036] In the present embodiment, each of the first extending portion 32j1 and the second extending portion 32j2 includes an inclined portion 32s1 that intersects obliquely with respect to the axial and circumferential directions between the first end face 30f1 and the bending positions P1, P2. The inclined portions 32s1 of the first extending portion 32j1 and the second extending portion 32j2 are spaced apart from each other in the axial and circumferential directions. A gap (space) is present throughout the entire portion where the inclined portions 32s1 of the first extending portion 32j1 and the second extending portion 32j2 are spaced apart in the direction along the inclination of the inclined portion 32s1.

[0037] In this embodiment, each of the first extending portion 32j1 and the second extending portion 32j2 includes a straight portion 32s2 that extends linearly in the axial direction between the portion where the power lines 35U, 35V, and 35W are connected and the bending positions P1 and P2. The straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 are arranged adjacent to each other in the circumferential direction. The straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 are arranged such that opposing side surfaces are in contact or close to each other in the circumferential direction. Note that the bending positions P1 and P2 are provided at the boundary between the inclined portion 32s1 and the straight portion 32s2 of each of the first extending portion 32j1 and the second extending portion 32j2 (in other words, between the upper end of the inclined portion 32s1 and the lower end of the straight portion 32s2).

[0038] In the present embodiment, the straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 are connected to the power lines 35U, 35V, and 35W at positions extending axially outward (upward) from positions adjacent to each other in the circumferential direction. When the circumferentially opposing side surfaces of the straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 contact each other, the straight portions 32s2 are connected to the power lines 35U, 35V, and 35W at positions extending axially outward (upward) from the contact surfaces (side surfaces).

[0039] In the present embodiment, the stator 3 further includes a connecting member 38 for connecting the power lines 35U, 35V, and 35W to each of the first extending portion 32j1 and the second extending portion 32j2. The connecting member 38 includes a cylindrical portion 38a to which the axial outer ends of each of the first extending portion 32j1 and the second extending portion 32j2 are connected, and an extending portion 38b extending from the cylindrical portion 38a and connected to the power lines 35U, 35V, and 35W.

[0040] This allows the axial outer ends of the first extending portion 32j1 and the second extending portion 32j2 to be crimped together and connected by the tubular portion 38a of the connecting member 38. In the example shown in the figure, the axial outer ends of the straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 are crimped together within the tubular portion 38a using a crimping joining method. Note that the axial outer ends of the straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 may be welded together, without being limited to the above. The manner in which the axial outer ends of the straight portions 32s2 are connected together can be changed depending on the design specifications.

[0041] The extension portion 38b extends axially outward (upward) from the cylindrical portion 38a. The extension portion 38b is connected to the terminals of the power lines 35U, 35V, and 35W by fastening with bolts and nuts. The extension portion 38b has through holes through which the bolts pass. Note that the manner of connection between the extension portion 38b and the terminals of the power lines 35U, 35V, and 35W is not limited to the above and can be changed according to design specifications.

[0042] In this embodiment, a plurality of power lines 35U, 35V, and 35W are provided. A plurality of connecting members 38 are provided corresponding to the plurality of power lines 35U, 35V, and 35W. The plurality of connecting members 38 are arranged at the same position in the axial direction. The connection positions between the extension portions 38b of the plurality of connecting members 38 and the terminals of the power lines 35U, 35V, and 35W (e.g., the center positions of the holes in the extension portions 38b through which the bolts pass) are arranged at the same position in the axial direction.

[0043] In the illustrated example, the multiple connecting members 38 have the same shape. However, the shapes of the multiple connecting members 38 are not limited to the above and may be different from each other. The shapes of the multiple connecting members 38 can be changed according to design specifications.

[0044] <Operation and Effect> As described above, the stator 3 of this embodiment includes a stator coil 31 wound around a cylindrical stator core 30. The stator coil 31 has a plurality of distal extensions 32e that extend outward from a first axial end face 30f1 of the stator core 30 and are aligned circumferentially around the stator core 30. The distal extensions 32e include first extensions 32j1 and second extensions 32j2 that are bent between the first end face 30f1 and the portions where the power lines 35U, 35V, and 35W are connected and adjacent to each other in the circumferential direction. The bending positions P1, P2 of the first extensions 32j1 and the second extensions 32j2 are different from each other in the axial direction. For example, FIG. 6 shows a case where the bending positions of the plurality of distal extensions are the same in the axial direction. In this case, the distal extensions are spaced apart circumferentially, making it difficult to connect them to the power lines. When multiple distal extension portions are spaced apart in the circumferential direction, the coils (the two distal extension portions surrounded by dashed lines in FIG. 6 ) must be connected to the power lines using other components (such as a bus bar). This results in issues such as poor assembly, an increased number of components, and increased size. In contrast, according to this embodiment, the bending positions P1, P2 of the first extension portion 32j1 and the second extension portion 32j2 are different from each other in the axial direction, allowing the coils (the first extension portion 32j1 and the second extension portion 32j2) to be closer to each other in the circumferential direction than in the comparative example of FIG. 6 . Therefore, the closer first extension portion 32j1 and the second extension portion 32j2 can be connected to the power lines 35U, 35V, and 35W, eliminating the need for other components (such as a bus bar). This improves assembly, reduces the number of components, and reduces the size.

[0045] In the present embodiment, the bending position P1 of the first extending portion 32j1 is positioned outward in the axial direction from the reference position Pc. The bending position P2 of the second extending portion 32j2 is positioned inward in the axial direction from the reference position Pc. For example, possible configurations for making the bending positions P1, P2 of the first extending portion 32j1 and the second extending portion 32j2 different from each other in the axial direction include leaving the bending position P1 of the first extending portion 32j1 unchanged and positioning the bending position P2 of the second extending portion 32j2 more inward in the axial direction than the first extending portion 32j1, or leaving the bending position P2 of the second extending portion 32j2 unchanged and positioning the bending position P1 of the first extending portion 32j1 more outward in the axial direction than the second extending portion 32j2. However, these configurations are difficult to accommodate when the target positions for connecting the first and second extension portions 32j1 and 32j2 to the power lines 35U, 35V, and 35W are set at predetermined circumferential positions (e.g., the center positions between the unconnected extension portions 32u circumferentially adjacent to the first and second extension portions 32j1 and 32j2). In contrast, according to the present embodiment, the bending positions P1 and P2 of the first and second extension portions 32j1 and 32j2 are located on opposite sides of the axial direction from the reference position Pc, making it easy to accommodate even when the target positions for connecting the first and second extension portions 32j1 and 32j2 to the power lines 35U, 35V, and 35W are set as described above.

[0046] In this embodiment, the distances D1 and D2 from the reference position Pc to the bending positions P1 and P2 of the first extending portion 32j1 and the second extending portion 32j2 are the same. This embodiment can more easily accommodate the above-described target positions for connecting the first extending portion 32j1 and the second extending portion 32j2 to the power lines 35U, 35V, and 35W.

[0047] In the present embodiment, each of the first extending portion 32j1 and the second extending portion 32j2 includes an inclined portion 32s1 that intersects obliquely with respect to the axial and circumferential directions between the first end face 30f1 and the bending positions P1, P2. The inclined portions 32s1 of the first extending portion 32j1 and the second extending portion 32j2 are arranged to be spaced apart from each other in the axial and circumferential directions. According to the present embodiment, dimensional errors and the like can be tolerated in the spaced apart portions of the inclined portions 32s1 of the first extending portion 32j1 and the second extending portion 32j2, which contributes to improved assembly ease in terms of dimensional errors and the like.

[0048] In the present embodiment, each of the first extending portion 32j1 and the second extending portion 32j2 includes a straight portion 32s2 that extends linearly in the axial direction between the portion where the power lines 35U, 35V, and 35W are connected and the bending positions P1 and P2. The straight portions 32s2 of the first extending portion 32j1 and the second extending portion 32j2 are arranged adjacent to each other in the circumferential direction. According to the present embodiment, the straight portions 32s2 that are adjacent to each other in the circumferential direction can be connected to the power lines 35U, 35V, and 35W, which contributes to further improving assembly, reducing the number of parts, and making the device more compact.

[0049] In this embodiment, the straight portions 32s2 of the first extension portion 32j1 and the second extension portion 32j2 are connected to the power lines 35U, 35V, and 35W at positions extending axially outward from positions adjacent to each other in the circumferential direction. For example, when connecting power lines to portions extending radially from a predetermined position, it is necessary to weld the radially extending portions together or connect them using other components (such as a bus bar or a resin unit). This likely increases the radial size of the stator and the overall size of the rotating electric machine, including the housing. In contrast, according to this embodiment, the straight portions 32s2 are connected to the power lines 35U, 35V, and 35W at positions extending axially outward from positions adjacent to each other in the circumferential direction, eliminating the need for other components (such as a bus bar or a resin unit). This contributes to further improving assembly, reducing the number of parts, and making the rotating electric machine more compact.

[0050] In this embodiment, the stator coil 31 is made of rectangular wire. This embodiment makes it easier to miniaturize the stator coil 31 compared to when the stator coil 31 is made of round wire, contributing to further miniaturization. Furthermore, rectangular wire is harder than round wire, so there are cases where it is desired to extend the wire straight. Even in this case, the straightened rectangular wire can be connected to the power lines 35U, 35V, and 35W at a position extended outward in the axial direction as described above, which is highly practical.

[0051] In this embodiment, the stator 3 further includes a connecting member 38 for connecting the power lines 35U, 35V, and 35W to the first and second extending portions 32j1 and 32j2, respectively. The connecting member 38 includes a cylindrical portion 38a to which the axial outer ends of the first and second extending portions 32j1 and 32j2 are connected, and an extending portion 38b extending from the cylindrical portion 38a and connected to the power lines 35U, 35V, and 35W. According to this embodiment, the axial outer ends of the first and second extending portions 32j1 and 32j2 are crimped together and connected by the cylindrical portion 38a of the connecting member 38, and the extending portion 38b extending from the cylindrical portion 38a can be connected to the power lines 35U, 35V, and 35W, eliminating the need for other components (such as bus bars) for connection. This contributes to further improving assembly, reducing the number of components, and making the stator 3 more compact.

[0052] In this embodiment, a plurality of power lines 35U, 35V, and 35W are provided. A plurality of connecting members 38 are provided corresponding to the plurality of power lines 35U, 35V, and 35W. Each of the plurality of connecting members 38 is disposed at the same position in the axial direction. This embodiment can easily accommodate a case where the target positions for connecting each of the plurality of connecting members 38 to the power lines 35U, 35V, and 35W are set at predetermined positions in the axial direction (for example, axial positions corresponding to the respective reference positions Pc).

[0053] However, increasing the number of parallel wires requires additional components (such as bus bars) to bundle the parallel wires together, resulting in issues such as poor assembly, an increased number of components, and increased size. Furthermore, connecting the stator to other components (such as bus bars) at the radially outermost windings increases the radial size of the stator, potentially increasing the radial size of the entire rotating electrical machine, including the housing. In contrast, this embodiment employs a configuration in which the bending positions P1, P2 of the first and second extensions 32j1, 32j2 in the innermost windings of the stator 3 are changed axially. Therefore, the straight portions 32s2 of adjacent rectangular wires can be connected to the power lines 35U, 35V, and 35W, eliminating the above-mentioned issues. This contributes to further improving assembly, reducing the number of components, and miniaturizing the machine.

[0054] <Modifications> In the above-described embodiment, an example has been described in which the bending position of the first extension portion is located axially outward from the reference position and the bending position of the second extension portion is located axially inward from the reference position, but this is not limited to this. For example, as a configuration for making the bending positions of the first extension portion and the second extension portion different from each other in the axial direction, the bending position of the second extension portion may be located axially inward from the bending position of the first extension portion, or the bending position of the first extension portion may be located axially outward from the bending position of the second extension portion. The configuration for making the bending positions of the first extension portion and the second extension portion different from each other in the axial direction can be changed according to design specifications.

[0055] In the above-described embodiment, the distances from the reference position to the bending positions of the first and second extension portions are the same, but this is not limiting. For example, the distances from the reference position to the bending positions of the first and second extension portions may be different. The distances from the reference position to the bending positions of the first and second extension portions can be changed according to design specifications.

[0056] In the above-described embodiment, the first extension portion and the second extension portion each include an inclined portion that intersects obliquely with respect to the axial and circumferential directions between the first end face and the bending position, and the inclined portions of the first extension portion and the second extension portion are arranged to be spaced apart from each other in the axial and circumferential directions. However, this is not limiting. For example, the inclined portions of the first extension portion and the second extension portion may be arranged to be in contact with each other. The arrangement of the inclined portions of the first extension portion and the second extension portion can be changed depending on the design specifications.

[0057] In the above-described embodiment, the first extension portion and the second extension portion each include a straight portion that extends linearly in the axial direction between the portion where the power line is connected and the bent position, and the straight portions of the first extension portion and the second extension portion are arranged adjacent to each other in the circumferential direction. However, this is not limited to this. For example, the straight portions of the first extension portion and the second extension portion may be arranged spaced apart from each other in the circumferential direction. The arrangement of the straight portions of the first extension portion and the second extension portion can be changed depending on the design specifications.

[0058] In the above-described embodiment, the linear portions of the first and second extension portions are connected to the power line at positions extending axially outward from positions adjacent to each other in the circumferential direction. However, this is not limiting. For example, each of the first and second extension portions may be connected to the power line at a portion extending radially from a predetermined position. The manner in which each of the first and second extension portions is connected to the power line can be changed depending on the design specifications.

[0059] In the above-described embodiment, the stator coil is made of rectangular wire, but this is not limiting. For example, the stator coil may be made of round wire. The configuration of the stator coil can be changed according to the design specifications.

[0060] In the above-described embodiment, the stator further includes a connecting member for connecting the power line to each of the first and second extension portions, and the connecting member includes a cylindrical portion to which the axial outer ends of the first and second extension portions are connected, and an extension portion extending from the cylindrical portion and connected to the power line. However, this is not limited to this. For example, the axial outer ends of each of the first and second extension portions may be connected to the power line via other components (such as bus bars). For example, the stator may not include the connecting member. The installation manner of the connecting member can be changed depending on the design specifications.

[0061] In the above-described embodiment, an example has been described in which a plurality of power lines are provided, a plurality of connecting members are provided corresponding to the plurality of power lines, and each of the plurality of connecting members is disposed at the same position in the axial direction, but this is not limiting. For example, each of the plurality of connecting members may be disposed at different positions in the axial direction. The arrangement of each of the plurality of connecting members can be changed according to design specifications.

[0062] In the above-described embodiment, the stator coil has been described as having three-phase winding groups connected in parallel, but this is not limiting. For example, the stator coil may have three-phase winding groups connected in series. The winding groups and the configuration of the stator (e.g., the relationship between poles, phases, and slots) can be changed according to design specifications.

[0063] In the above-described embodiment, the stator coil is described as including a plurality of U-shaped segment coils whose ends are connected to each other, but this is not limiting. For example, the stator coil may include a coil wound in a continuous wave pattern. The configuration of the stator coil can be changed according to the design specifications.

[0064] In the above-described embodiment, the rotating electric machine includes a rotor, the stator, and a housing that accommodates the rotor and the stator, and the plurality of distal extensions are disposed on the axially opposite side of the housing from the bottom. However, this is not limiting. For example, the plurality of distal extensions may be disposed on the same axial side of the housing as the bottom (opposite the opening). The arrangement of the plurality of distal extensions can be changed according to design specifications.

[0065] In the above-described embodiment, the rotating electric machine is mounted on an electric swing shovel, and an electric swing motor for swinging the upper swing body of the electric swing shovel has been described as an example, but the present invention is not limited to this. For example, the rotating electric machine may be mounted on other work machines such as a wheel loader, a bulldozer, or a dump truck. For example, the rotating electric machine may be configured as a drive motor for driving a work machine or a drive motor for driving a traveling device. The type of work machine on which the rotating electric machine is mounted and the object that the rotating electric machine drives can be changed depending on the design specifications.

[0066] In the above-described embodiment, the rotating electric machine is described as being vertically disposed so that the rotor shaft is parallel to the rotation axis, but this is not limiting. For example, the rotating electric machine may be horizontally disposed so that the rotor shaft is perpendicular to the rotation axis. For example, the rotating electric machine may be disposed at an angle so that the rotor shaft intersects the rotation axis at an angle. The arrangement of the rotating electric machine can be changed according to the design specifications.

[0067] In the above-described embodiment, the rotating electric machine is an inner rotor type rotating electric machine in which a stator is disposed outside a cylindrical rotor, but the present invention is not limited to this. For example, the rotating electric machine may be an outer rotor type rotating electric machine in which a stator is disposed inside a cup-shaped rotor. The type of rotating electric machine can be changed depending on the design specifications.

[0068] In the above-described embodiment, the rotating electric machine is described as a motor that drives and rotates a rotor by passing an alternating current through a stator coil, but the present invention is not limited to this. For example, the rotating electric machine may be a generator that generates electricity by rotating a rotor using power from an engine or the like. The configuration of the rotating electric machine can be changed according to design specifications.

[0069] Although one embodiment has been described above with reference to the drawings, the specific configuration is not limited to that described above, and additions, omissions, substitutions, and other modifications to the configuration are possible within the scope of the present disclosure, and the above-described embodiments can also be combined as appropriate.

[0070] DESCRIPTION OF SYMBOLS 1...Rotating electric machine, 3...Stator, 30...Stator core, 30f1...First end surface, 31...Stator coil, 32e...End side extension portion, 32j1...First extension portion, 32j2...Second extension portion, 32s1...Inclined portion, 32s2...Straight portion, 35U, 35V, 35W...Power line, 38...Connecting member, 38a...Cylindrical portion, 38b...Extended portion, 100...Work machine, 114...Swing motor, 120...Traveling body, 140...Upper swing body, 160...Work machine, D1, D2...Distance, P1, P2...Bending position, Pc...Reference position

Claims

1. A stator comprising a stator coil wound around a cylindrical stator core and having a plurality of end-side extending portions that extend outward from a first end face in the axial direction of the stator core and are arranged in the circumferential direction of the stator core, wherein the plurality of end-side extending portions include a first extending portion and a second extending portion that are bent between a portion to which a power line is connected and the first end face and are adjacent to each other in the circumferential direction, and bending positions of each of the first extending portion and the second extending portion are different from each other in the axial direction.

2. The stator according to claim 1, wherein the bending position of the first extending portion is arranged outside the reference position in the axial direction, and the bending position of the second extending portion is arranged inside the reference position in the axial direction.

3. The stator according to claim 2, wherein distances of the bending positions of each of the first extending portion and the second extending portion from the reference position are the same as each other.

4. The stator according to claim 1 or 2, wherein each of the first extending portion and the second extending portion includes an inclined portion that obliquely intersects the axial direction and the circumferential direction between the first end face and the bending position, and the inclined portions of each of the first extending portion and the second extending portion are arranged to be spaced apart from each other in the axial direction and the circumferential direction.

5. The stator according to claim 1 or 2, wherein each of the first extending portion and the second extending portion includes a straight portion that extends linearly along the axial direction between a portion to which the power line is connected and the bending position, and the straight portions of each of the first extending portion and the second extending portion are arranged to be adjacent to each other in the circumferential direction.

6. The stator according to claim 5, wherein the straight portions of each of the first extending portion and the second extending portion are connected to the power line at positions extended outward in the axial direction from positions adjacent to each other in the circumferential direction.

7. The stator according to claim 1 or 2, wherein the stator coil is formed of a flat wire.

8. The stator according to claim 1 or 2, further comprising a connecting member for connecting the power line to each of the first extending portion and the second extending portion, the connecting member including a cylindrical tubular portion to which outer end portions in the axial direction of each of the first extending portion and the second extending portion are connected, and an extending portion that extends from the tubular portion and is connected to the power line.

9. A plurality of the power lines are provided, a plurality of the connection members are provided corresponding to the plurality of the power lines, and each of the plurality of the connection members is arranged at the same position as each other in the axial direction. The stator according to claim 8.

10. A rotating electrical machine comprising a rotor, the stator according to claim 1 or 2, and a housing that houses the rotor and the stator.

11. A working machine comprising a traveling body, an upper swing body that is swingably supported by the traveling body around a swing axis, a working device that is operably supported by the upper swing body, and the rotating electrical machine according to claim 10 configured as a swing motor for swinging the upper swing body with respect to the traveling body.

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