Rotary electric machine

Abstract

This rotary electric machine comprises a stator and a rotor, the stator including an annular core, a plurality of conductors, and a joint part that joints the conductors to each other by welding. In a radial direction, among the plurality of conductors, a linear part of one conductor and a linear part of the other conductor are arranged side by side. A cross-sectional area of the linear part of the other conductor is larger than a cross-sectional area of the linear part of the one conductor. The joint part is formed by welding an end part of the one conductor and an end part of the other conductor. In the joint part, a distance in an axial direction between the outer side of the other conductor and the core is larger than a distance in the axial direction between the outer side of the one conductor and the core.

Description

Rotating electrical machine

[0001] The present invention relates to a rotating electrical machine.

[0002] In a motor, terminals of a neutral wire, a U-phase, a V-phase, and a W-phase are fixed on the side where the output line is arranged. For this fixing, welding strength capable of withstanding vibration and impact load is required. Patent Document 1 below discloses a welding method for suppressing the generation of blow holes, which are welding defects, in a welded portion by a constant current.

[0003] Japanese Patent Application Laid-Open No. 2023-15062

[0004] In the configuration described in Patent Document 1, since the welding surface is flat, when the size of the coil is small, the welding area becomes small, and there arises a problem that the welding strength for fixing the terminal is insufficient.

[0005] A rotating electrical machine including a stator including an annular core, a plurality of conductors, and a joint portion that welds and joins the conductors to each other, and a rotor, wherein in the radial direction, among the plurality of conductors, a straight portion of one conductor and a straight portion of another conductor are arranged side by side, the cross-sectional area of the straight portion of the other conductor is larger than the cross-sectional area of the straight portion of the one conductor, the joint portion is formed by welding an end portion of the one conductor and an end portion of the other conductor, and in the joint portion, a distance in the axial direction between the outside of the other conductor and the core is larger than a distance in the axial direction between the outside of the one conductor and the core.

[0006] A rotating electrical machine capable of improving the welding strength of the coil end and improving reliability can be provided.

[0007] Overall perspective view of a rotating electrical machine according to an embodiment of the present invention and enlarged view of part A, Cross-sectional view for explaining welding between a terminal and a coil according to an embodiment of the present invention, Enlarged view of part B of FIG. 1 according to an embodiment of the present invention, First modification, Second modification

[0008] Embodiments of the present invention will be described below with reference to the drawings. The following description and drawings are illustrative for illustrating the present invention, and have been omitted and simplified as appropriate for clarity of explanation. The present invention can also be carried out in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] The positions, sizes, shapes, and ranges of the components shown in the drawings may not represent their actual positions, sizes, shapes, and ranges in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the positions, sizes, shapes, and ranges disclosed in the drawings.

[0010] (An Embodiment and Overall Configuration) (Figures 1 to 3) In the following description, Figure 1(a) of Figure 1 is an overall perspective view of the stator 1 of the rotating electric machine, and Figure 1(b) is an enlarged view of part A of the stator 1 of the rotating electric machine. Also, Figure 2(a) of Figure 2 illustrates a state in which the coil 5 is welded to both sides of the terminal 2, Figure 2(b) illustrates a state in which the coil 5 is welded to one side of the terminal 2, and Figure 2(c) illustrates a state in which the coil 5 is welded to the other side of the terminal 2. Figure 3 is an enlarged view of part B of Figure 1(a).

[0011] The stator 1 of a rotating electric machine has a coil 5, which is a conductor, inserted into a ring-shaped stator core 1a. The coil 5 is exposed to the outside of the stator core 1a as coil ends from both end faces of the stator core 1a. In the stator core 1a, the coil 5 exposed from one end face is connected to a terminal 2, which is a conductor containing multiple conductive members, namely a neutral wire, U-phase, V-phase, and W-phase. The multiple conductive members are integrated with resin or the like to form the terminal 2, ensuring insulation from each other. In the stator core 1a, the coil 5 exposed from the other end face is welded to each other by a joint 3. The welding that forms the joint 3 is, for example, TIG (Tungsten Inert Gas) welding or laser welding.

[0012] Although not shown in the figures, the rotating electric machine has a rotor on the inner circumference side of the stator 1. This rotor is supported so as to be rotatable coaxially with the stator core 1a. The coils 5 pass through slots (not shown) provided in the stator core 1a, aligned radially.

[0013] The radial direction is defined as the first direction, and the axial direction as the second direction. In the stator core 1a, the coil 5 exposed on the terminal 2 side is arranged alongside the terminal 2 in the first direction. One conductor, coil 5, includes an inner coil 11 arranged on the inner circumference side of the terminal 2, which is the other conductor, and an outer coil 12 arranged on the outer circumference side of the terminal 2. Within the slot of the stator core 1a, the inner coil 11 is arranged on the inner circumference side of the terminal 2, and the outer coil 12 is arranged on the outer circumference side of the terminal 2.

[0014] The inner coil 11 and outer coil 12, which are conductors, are electrically connected to each other via the terminal 2, which is the other conductor. The inner coil 11 is positioned in the slot on the side closest to the rotor (not shown).

[0015] Terminal 2 extends circumferentially from the stator core 1a. This is referred to as the first conductive portion 2a. Terminal 2 has a second conductive portion 2b that protrudes radially from the first conductive portion 2a, and a third conductive portion 2c that extends axially from the second conductive portion 2b with respect to the outside of the stator core 1a. The third conductive portion 2c is a straight portion that is welded to the straight portion of the coil 5 at terminal 2.

[0016] In the inner coil 11, the end of the straight section 11a, which is the coil end portion to be welded, is welded to the end of the straight section 2c of the terminal 2, which is the other conductor arranged radially, thereby forming a joint 3. Similarly, in the outer coil 12, the end of the straight section 12a, which is the coil end portion to be welded, is welded to the end of the straight section 2c of the terminal 2, which is the other conductor arranged radially, thereby forming a joint 3. Note that, as shown in Figures 2(b) and 2(c), the configuration for forming the joint 3 is the same even when the coils 5 are not arranged side by side on the inner and outer circumferences of the terminal 2.

[0017] The cross-sectional area of ​​the other conductor, the straight section 2c, is larger than the cross-sectional area of ​​the other conductor, the straight section 11a. Furthermore, at the joint 3, the distance 13 in the second direction between the outside of the other conductor, the straight section 2c, and the stator core 1a is larger than the distance 13a in the second direction between the outside of the one conductor, the straight section 11a (12a), and the stator core 1a.

[0018] As a result, the straight section 11a (12a) has a smaller cross-sectional area than the straight section 2c, so when forming the joint 3, the straight section 11a (12a) melts faster than the end of the straight section 2c, and the joint 3 is formed in an oblique shape relative to the end face of the stator core 1a. In this way, the welding area of ​​the joint 3 is increased compared to conventional methods, and the stress related to the stress concentration points that occur in the joint 3 can be reduced, thus improving the welding strength. Furthermore, conventional welding equipment and welding methods can be used. In addition, the oblique formation of the joint 3 contributes to reducing the height of the coil end, which is the exposed portion from the stator core 1a in the coil 5.

[0019] As shown in Figure 3, in the stator core 1a, the coil 5 on the side opposite to the terminal 2 is joined to a joint 3 by welding one coil peeling portion 5a to the other coil peeling portion 5b. For example, when welding two coils 5 of the same cross-sectional area, the joint 3 is formed in an oblique shape by making the degree of peeling of the coil peeling portion 5a and the degree of peeling of the coil peeling portion 5b different from each other. In this way, the welding area at the joint 3 is increased, and the welding strength is improved.

[0020] Furthermore, the terminal 2 may be covered with resin in all parts except the peeled portion related to the joint 3, and since at least a part of it is covered with resin, the terminal 2 can be made insulating.

[0021] (First modified example, second modified example) (Figure 4) Figure 4(a) illustrates the first modified example, and Figure 4(b) illustrates the second modified example. As with the welding joint between the coils 5 described above in Figure 3, in Figure 4(a), the degree of peeling of one coil peeling portion 5a is greater than the degree of peeling of the other coil peeling portion 5b, so the shape of the joint portion 3 is oblique. However, as shown in Figure 4(b), even when the cross-sectional area of ​​the first coil 5c is larger than the cross-sectional area of ​​the second coil 5d, the joint portion 3 can be similarly formed in an oblique shape.

[0022] According to the embodiments of the present invention described above, the following effects and advantages are achieved.

[0023] (1) A rotating electric machine comprising a stator 1 having an annular core 1a, a plurality of conductors, and a joint 3 for welding the conductors together, and a rotor, wherein in the radial direction, the straight portion of one conductor 5 and the straight portion 2c of the other conductor 2 are arranged side by side, the cross-sectional area of ​​the straight portion 2c of the other conductor 2 is larger than the cross-sectional area of ​​the straight portion of the one conductor 5, the joint 3 is formed by welding the end of one conductor 5 and the end of the other conductor 2, and at the joint, the axial distance between the outside of the other conductor 2 and the core 1a is greater than the axial distance between the outside of the one conductor and the core 1a. In this way, a rotating electric machine can be provided that improves the welding strength of the coil ends and improves reliability.

[0024] (2) Multiple conductors 5 pass through slots provided in the core 1a, aligned radially. This makes it possible to realize the configuration of the present invention as described above.

[0025] (3) One conductor 5 passes through multiple slots provided in the core 1a in a radial direction, and the multiple one conductors 5 are electrically connected to each other via the other conductor 2. In this way, the configuration of the present invention described above can be realized.

[0026] (4) The other conductor 2 comprises a first conductive portion 2a extending in the circumferential direction, a second conductive portion 2b projecting radially from the first conductive portion 2a, and a third conductive portion 2c extending axially from the second conductive portion 2b toward the outside of the core. The joint portion 3 is formed by welding the end of one conductor 5 to the end of the third conductive portion 2c, which is arranged radially side by side. In this way, a diagonally shaped joint portion 3 can be formed.

[0027] (5) One conductor 5 is positioned on the inner circumference side of the slot than the other conductor 2, and the joint 3 is formed by welding the end of the one conductor 5 positioned on the inner circumference side to the end of the other conductor 2. This makes it possible to improve the welding strength of the coil end on the inner circumference side.

[0028] (6) The rotor is supported so as to be rotatable coaxially with the core 1a, and one of the conductors 5, which is located on the inner circumference side, is located in the slot closest to the rotor. In this way, the configuration of the present invention described above can be realized.

[0029] (7) One conductor 5 is positioned on the outer circumference side of the slot than the other conductor 2, and the joint 3 is formed by welding the end of the conductor 5 positioned on the outer circumference side to the end of the other conductor 2. This makes it possible to improve the welding strength of the coil end on the outer circumference side.

[0030] (8) One conductor 5 is positioned in the slot on the inner circumference side and on the outer circumference side of the other conductor 2. This arrangement improves the welding strength of the coil ends on both sides of the terminal 2.

[0031] (9) At least a portion of the other conductor 2 is covered with resin. This ensures insulation.

[0032] (10) The other conductor 2 includes a plurality of conductive members, and the plurality of conductive members are integrated with resin. This ensures insulation.

[0033] It should be noted that the present invention is not limited to the embodiments described above, and various modifications and combinations of other configurations can be made without departing from the spirit of the invention. Furthermore, the present invention is not limited to having all the configurations described in the embodiments described above, and may also include configurations in which some of those configurations are omitted.

[0034] 1 Stator 1a Stator core 2 Terminal 2a First conductive part 2b Second conductive part 2c Third conductive part 3 Joint 5 Coil 5a One coil peeling part 5b The other coil peeling part 5c First coil 5d Second coil 11 Inner circumference coil 11a Straight part 12 Outer circumference coil 12a Straight part 13 Distance from terminal side stator core to weld 13a Distance from coil side stator core to weld

Claims

1. A rotating electric machine comprising a stator having an annular core, a plurality of conductors, and a joint for welding the conductors together, and a rotor, wherein in the radial direction, the straight portion of one conductor and the straight portion of the other conductor are arranged side by side, the cross-sectional area of ​​the straight portion of the other conductor is larger than the cross-sectional area of ​​the straight portion of the one conductor, the joint is formed by welding the end of one conductor to the end of the other conductor, and at the joint, the axial distance between the outside of the other conductor and the core is greater than the axial distance between the outside of the one conductor and the core.

2. A rotating electric machine according to claim 1, wherein the plurality of conductors penetrate through slots provided in the core in a radial direction.

3. A rotating electric machine according to claim 1, wherein one of the conductors passes through a plurality of slots provided in the core in the radial direction, and the plurality of the one conductors are electrically connected to each other via the other conductor.

4. A rotating electric machine according to claim 3, wherein the other conductor comprises a first conductive portion extending in the circumferential direction, a second conductive portion projecting radially from the first conductive portion, and a third conductive portion extending axially from the second conductive portion with respect to the outer direction of the core, and the joint is formed by welding the end of one conductor and the end of the third conductive portion arranged radially side by side.

5. A rotating electric machine according to claim 3, wherein one conductor is positioned in the slot on the inner circumference side of the other conductor, and the joint is formed by welding the end of the one conductor positioned on the inner circumference side to the end of the other conductor.

6. A rotating electric machine according to claim 5, wherein the rotor is rotatably supported coaxially with the core, and the one conductor disposed on the inner circumference is disposed in the slot closest to the rotor.

7. A rotating electric machine according to claim 3, wherein one conductor is positioned in the slot on the outer circumference side of the other conductor, and the joint is formed by welding the end of the one conductor positioned on the outer circumference side to the end of the other conductor.

8. A rotating electric machine according to claim 4, wherein one conductor is arranged in the slot on an inner circumference side of the other conductor and on an outer circumference side of the other conductor.

9. A rotating electric machine according to claim 3, wherein at least a portion of the other conductor is covered with resin.

10. A rotating electric machine according to claim 9, wherein the other conductor includes a plurality of conductive members, and the plurality of conductive members are integrated with the resin.

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