Strip coil manufacturing method and strip coil

Abstract

To provide a manufacturing method of a strip coil capable of preventing disorder of an arrangement state of wire constituting conductor wire.SOLUTION: A manufacturing method of a strip coil in which conductor wire 1 is folded and shaped multiple times to form a strip shape, the conductor wire composed of two or more wires 11 housed in parallel in a slot of a stator core. In the manufacturing method of the strip coil, the wires 11 and 11 of at least one end 1a of the conductive wire 1 are joined to each other before bending the conductive wire 1.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a strip coil and a strip coil. [Background technology]

[0002] A stator of a rotating electric machine such as an electric motor or generator is composed of a stator core and coils fitted into slots in the stator core. A known coil is a strip-shaped coil formed into a long strip along the circumferential direction of the stator core. The strip-shaped coil is manufactured by repeatedly bending a conductor wire into a U-shape, bending the straight portion of the conductor wire into an inclined shape, and then folding back the inclined portion to form a mountain-shaped coil end (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-58076 Summary of the Invention [Problem to be solved by the invention]

[0004] A single conductor wire is composed of two or more wire rods arranged in parallel. Therefore, when the straight portion of a single conductor wire constituting a strip-shaped coil is inserted into a slot of a stator core, two or more wire rods are arranged in parallel within the slot. However, when a conductor wire consisting of two or more parallel wire rods is bent and formed, the arrangement of the wire rods may become disordered at the end of the conductor wire. If the arrangement of the wire rods becomes disordered, the wire rods may separate during subsequent forming operations, and each wire rod may become entangled or caught in the forming device, causing problems during the forming operation. The above-mentioned prior art does not disclose a method for actively preventing such disorder in the arrangement of the wire rods.

[0005] The present invention aims to provide a method for manufacturing a strip coil that can prevent disturbance in the arrangement of the wires that make up the conductor wire, and to provide a strip coil in which the arrangement of the wires that make up the conductor wire is not disturbed. [Means for solving the problem]

[0006] (1) The method for manufacturing a strip-shaped coil according to the present invention is a method for manufacturing a strip-shaped coil (e.g., a strip-shaped coil 2 described later) in which a conductor wire (e.g., a conductor wire 1 described later) consisting of two or more wire rods (e.g., wire rods 11 described later) accommodated in parallel in a slot (e.g., slot 34 described later) of a stator core (e.g., stator core 31 described later) is folded and shaped multiple times to form a strip-shaped coil, and before folding and shaping the conductor wire, the wire rods at at least one end (e.g., end 1a described later) of the conductor wire are joined together.

[0007] (2) In the method for manufacturing a strip-shaped coil described in (1) above, the wires are joined by twist joining.

[0008] (3) In the method for manufacturing a strip-shaped coil according to (2) above, the twist joint involves twisting the end of the conductor wire by 270° or more.

[0009] (4) In the method for manufacturing a strip-shaped coil according to any one of (1) to (3) above, the one end of the conductor wire that joins the wire rods together is the end on the side that is to be finally bent.

[0010] (5) In the method for manufacturing a strip-shaped coil according to any one of (1) to (3) above, the wire is a rectangular wire.

[0011] (6) The strip-shaped coil according to the present invention is a strip-shaped coil (e.g., strip-shaped coil 2 described later) formed by bending a conductor wire (e.g., conductor wire 1 described later) consisting of two or more wire rods (e.g., wire rod 11 described later) housed in parallel in a slot (e.g., slot 34 described later) of a stator core (e.g., stator core 31 described later) multiple times, and has a joint (e.g., twist joint 1b, welded joint 1c described later) at least on one end (e.g., end 1a described later) of the conductor wire where the wire rods are joined together.

[0012] (7) In the strip-shaped coil described in (6) above, the joint is a twist joint (for example, a twist joint 1b described later).

[0013] (8) In the strip-shaped coil described in (7) above, the twisted joint is formed by twisting the end of the conductor wire by 270° or more.

[0014] (9) In the strip coil described in (7) or (8) above, the twisted joints of the conductor wires have at least one of a twist angle and a twist direction that differ for each phase (e.g., U phase, V phase, and W phase described below).

[0015] (10) In the strip-shaped coil described in (6) to (8) above, the wire is a rectangular wire. [Effects of the Invention]

[0016] According to the above (1), the two or more wires constituting the conductor wire are joined together before bending the conductor wire, so the arrangement of the wires is not disturbed when the conductor wire is bent. Therefore, there is no risk of the wires separating when the conductor wire is bent, and problems such as the separated wires getting caught or entangled in the forming device are prevented.

[0017] According to the above (2), wires can be joined together easily and inexpensively by simply twisting at least one end of the conductor wire.

[0018] According to the above (3), the wires can be more reliably entangled with each other.

[0019] According to the above (4), it is possible to continuously prevent the arrangement of the wire rods from becoming disordered from the start to the end of the formation of the strip-shaped coil.

[0020] According to the above (5), even if rectangular wires, which tend to be easily disorganized, are used as the wires, it is possible to effectively prevent the wires from being disorganized when the conductor wires are bent.

[0021] According to (6) above, a joint where the wires are joined together is formed at at least one end of the conductor wire, making it possible to provide a strip-shaped coil in which the arrangement of the wires constituting the conductor wire is not disturbed. When the ends of each conductor wire are used as connection terminals for the strip-shaped coil, the wires of the connection terminals are not disturbed, so there is no need to align the tips of the parallel wires in the same slot in the terminal connection process. This makes it easy to make electrical connections to harnesses, etc.

[0022] According to the above (7), a strip-shaped coil in which wire rods are joined together can be easily and inexpensively provided by simply twisting at least one end of the conductor wire.

[0023] According to the above (8), it is possible to easily and inexpensively provide a strip-shaped coil in which wire rods are more reliably entangled and joined together.

[0024] According to the above (9), when the ends of the conductor wires having the twisted joints are used as connection terminals, it is possible to easily distinguish between the phases. Therefore, electrical connection with a harness or the like can be performed without confusion between the phases.

[0025] According to (10) above, even if flat wire, which is prone to disordering, is used as the wire, a strip coil can be provided in which the disordering of the wires is effectively prevented when the conductor wire is bent and formed. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] 10A and 10B are diagrams illustrating how one end of a conductor wire is twisted and joined; [Figure 4] 10A and 10B are diagrams illustrating how one end of a conductor wire is twisted and joined; [Figure 5] FIG. 2 is an enlarged view showing a twisted joint of the conductor wires. [Figure 6] 10A to 10C are diagrams illustrating a method for manufacturing a strip coil. [Figure 7] 10A to 10C are diagrams illustrating a method for manufacturing a strip coil. [Figure 8] 10A to 10C are diagrams illustrating a method for manufacturing a strip coil. [Figure 9] FIG. 2 is a schematic diagram showing a strip-shaped coil. [Figure 10] FIG. 10 is an enlarged view of part B in FIG. [Figure 11] 10A and 10B are diagrams illustrating examples in which the twist angles of the twisted joints of the conductor wires are changed. [Figure 12] 10A and 10B are diagrams showing examples in which the twist angle and twist direction of the twisted joint portion of the conductor wire are changed; [Figure 13] FIG. 2 is a plan view showing a stator on which a strip-shaped coil is mounted. [Figure 14] FIG. 2 is an enlarged view showing one slot of the stator. [Figure 15] FIG. 10 is an enlarged view showing a joint portion at one end of a conductor wire according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Figures 1 and 2 show one conductor wire 1 that constitutes a strip-shaped coil. Here, the directions of the conductor wire 1 shown in the figures will be defined. The X direction indicates the width direction of the conductor wire 1. The Y direction indicates the length direction of the conductor wire 1. The Z direction indicates the thickness direction of the conductor wire 1.

[0028] A single conductor wire 1 is formed in a long, linear shape in the length direction Y by arranging multiple wire rods 11 made of metal wires such as copper wires in parallel in the width direction X of the conductor wire 1. In this embodiment, a single conductor wire 1 is made up of two wire rods 11, 11. However, the number of wire rods 11 constituting a single conductor wire 1 may be two or more. Therefore, a single conductor wire 1 may be made up of three or more wire rods 11 arranged in parallel.

[0029] As shown in Fig. 2, each wire 11 is made of a rectangular wire having a substantially rectangular cross section. The surface of the wire 11 is covered with a resin insulating coating (not shown). Two wires 11 made of rectangular wire are arranged side by side with one flat surface of each wire in close contact with each other, and are parallel to each other in the width direction X of the conductor wire 1. In other words, one conductor wire 1 is a long metal wire in which two wires 11, 11 are arranged side by side.

[0030] Next, a method for manufacturing a strip-shaped coil using this conductor wire 1 will be described with reference to Figures 3 to 9. First, before performing bending to form a strip-shaped coil, parallel wire rods 11, 11 are joined together at least at one end 1a of the conductor wire 1.

[0031] 3 and 4 show a process for joining wire rods 11, 11 of a conductor wire 1. A joining device 100 for joining wire rods 11, 11 is shown in FIGS. 3 and 4. The joining device 100 includes a holding jig 101 for holding the conductor wire 1 and a twisting jig 102 for twisting the end 1a of the conductor wire 1. The twisting jig 102 has a rotation shaft 102a connected to a drive source (not shown) and is rotatable about the rotation shaft 102a.

[0032] 3, the conductor wire 1 is clamped in the width direction X by a gripping jig 101 near the end 1a. The end 1a of the conductor wire 1 protrudes a predetermined length from the gripping jig 101. The twisting jig 102 moves toward the gripping jig 101 and grasps and fixes the end 1a of the conductor wire 1 protruding from the gripping jig 101.

[0033] Next, as shown in Fig. 4, the twisting jig 102, which grips and fixes the end 1a of the conductor wire 1, rotates in one direction around the rotation axis 102a. At this time, the gripping jig 101 does not rotate. Therefore, the end 1a of the conductor wire 1 protruding from the gripping jig 101 is twisted in one direction by the rotation of the twisting jig 102. As a result, as shown in Fig. 5, a twisted joint 1b is formed at the end 1a of the conductor wire 1, where the wire rods 11, 11 are twisted and joined so that they are intertwined with each other.

[0034] The twisting jig 102 preferably rotates 270° or more in one direction. Because the end 1a of the wire conductor 1 is twisted 270° or more, the two wires 11, 11 are more firmly intertwined with each other to form a twisted joint 1b. This reliably prevents the two wires 11, 11 from being separated in the width direction X and length direction Y of the wire conductor 1.

[0035] In this embodiment, the wire rods 11 are joined to each other at both ends 1a of the conductor wire 1. By joining the wire rods 11 to each other at both ends 1a of the conductor wire 1, it is possible to reliably prevent separation of the wire rods 11 of one conductor wire 1. However, the wire rods 11 may be joined to each other at only one end 1a of the conductor wire 1.

[0036] The conductor wire 1, which has twisted joints 1b, 1b formed at both ends 1a, 1a, respectively, is bent into a U-shape in the width direction X of the conductor wire 1 using a drawing tool 200 that moves in the direction of the outline arrow, as shown in Fig. 6. As a result, the conductor wire 1 is formed into a U-shape having a mountain-shaped portion 12 and two straight portions 13, 13 extending parallel to each other in the same direction from both ends of the mountain-shaped portion 12.

[0037] As shown in FIG. 7, the strip coil is formed using a plurality of U-shaped conductor wires 1. In this embodiment, six conductor wires 1 are stacked. The six U-shaped conductor wires 1 are stacked in parallel with their mountain-shaped portions 121 aligned on the same side, shifted in position in the width direction X by a predetermined distance corresponding to the pitch of the slots 34 of the stator core 31 (see FIGS. 11 and 12). The twelve straight portions 13 are arranged in parallel at a predetermined distance apart. The twelve twisted joints 1b are arranged at the ends of the straight portions 13 and are parallel to each other.

[0038] The six overlapping conductor wires 1 are formed into a strip shape by repeatedly bending them multiple times using an appropriate forming device (not shown), starting from the side closest to the mountain-shaped portion 12. In this way, a strip-shaped coil 2 is formed.

[0039] 8, first, the six conductor wires 1 are bent from the side closest to the mountain-shaped portions 12 so that the straight portions 13 are inclined in the width direction X of the conductor wire 1, leaving only the straight portions 13 that will become the slot insertion portions 21 to be inserted into the slots 34 of the stator core 31. Then, the six conductor wires 1 are folded back in the thickness direction Z at the inclined portions. This forms the mountain-shaped coil end portions 22. The straight portions 13 (slot insertion portions 21) of the six folded back conductor wires 1 overlap one another in the thickness direction Z of the conductor wire 1, with a shift of six wires in the width direction X of the conductor wire 1.

[0040] Thereafter, the same bending process as above is repeated so that the slot insertion portions 21 and the coil end portions 22 are formed alternately. As a result, a strip-shaped coil 2 that is long in one direction is formed, as shown schematically in Fig. 9. The strip-shaped coil 2 has a plurality of slot insertion portions 21 formed by the straight portions 13 of the conductor wire 1, a plurality of coil end portions 22 arranged at both ends in the extension direction of the slot insertion portions 21, and twelve terminal portions 23 formed by both ends 1a of the conductor wire 1.

[0041] 9, the D1 direction is the length direction of the strip-shaped coil 2. The D1 direction corresponds to the width direction X of the conductor wire 1 and the circumferential direction of the stator core 31. The D2 direction is the width direction of the strip-shaped coil 2 and the extension direction of the slot insertion portion 21. The D2 direction corresponds to the axial direction of the stator core 31.

[0042] As shown in FIG. 10 , the twelve terminals 23 of the strip-shaped coil 2 have twisted joints 1b provided at the end 1a of each conductor wire 1. The end 1a of the conductor wire 1 where the twisted joints 1b are provided is the end on the side where the conductor wire 1 is last bent during the formation of the strip-shaped coil 2. By providing the twisted joints 1b at the end 1a of the conductor wire 1, it is possible to continuously prevent the arrangement of the wire rods 11, 11 from becoming distorted from the start to the end of the bending process. This allows the strip-shaped coil 2 to be formed stably while maintaining the joint state between the wire rods 11, 11 of the conductor wire 1. Furthermore, when the end 1a of each conductor wire 1 is used as a connection terminal for the strip-shaped coil 2, the wire rods 11, 11 of the connection terminals are not distorted, eliminating the need to align the tips of the parallel wire rods in the same slot during the terminal connection process. This facilitates electrical connection to a harness or the like.

[0043] When the strip coil 2 is, for example, a coil for three-phase alternating current of U-phase, V-phase, and W-phase, at least one of the twist angle and the twist direction of the conductor wire 1 at the twist joint 1b may be made different for each phase. FIG. 11 shows an example in which the twist angles of the twist joints 1b of the conductor wires 1 of each phase are formed such that U-phase < V-phase < W-phase. In this case, due to the different twist angles of the conductor wire 1, the lengths of the twist joints 1b along the extending direction of the conductor wire 1 are different for each phase. FIG. 12 shows an example in which the twist angles of the conductor wire 1 are made different for the twist joints 1b of U-phase and V-phase, and only the twist direction of the twist joint 1b of W-phase is made different. Thus, by making at least one of the twist angle and the twist direction of the conductor wire 1 at the twist joint 1b different for each phase, when using the end portion 1a of the conductor wire 1 as a connection terminal, each phase can be easily distinguished, so that the electrical connection with a harness or the like can be made without confusion for each phase. However, all or some of the twist joints 1b of the strip coil 2 may be cut and removed as necessary after the formation of the strip coil 2 is completed.

[0044] FIG. 13 shows a stator 3 having a strip coil 2. The stator 3 is composed of a stator core 31 and a strip coil 2 attached to the stator core 31. The stator core 31 has a plurality of teeth 33 protruding toward the central shaft hole 32. Slots 34 are formed between adjacent teeth 33, 33, arranged radially and opening toward the shaft hole 32. In FIG. 13, the strip coil 2 is schematically shown by a spiral arrow line.

[0045] The strip-shaped coil 2 is mounted so as to wrap around the stator core 31 in the circumferential direction by inserting the slot insertion portions 21 into each slot 34. The slot insertion portions 21 are made of a conductor wire 1 in which two wire rods 11 are arranged in parallel. Therefore, as shown in FIG. 14 , the wire rods 11 constituting one slot insertion portion 21 are accommodated in the slot 34 in the circumferential direction of the stator core 31 in parallel. The conductor wire 1 in which the wire rods 11 are twisted and joined together does not have any disorder in the arrangement of the wire rods 11. Therefore, the slot insertion portions 21 of the strip-shaped coil 2 formed by this conductor wire 1 are arranged in an orderly manner without disturbing the arrangement of the wire rods 11. This allows the stator 3 to have a high space factor.

[0046] In the above embodiment, the wire rods 11, 11 are twisted and joined together at the end 1a of the conductor wire 1, but the joining of the wire rods 11, 11 is not limited to twisting. For example, as shown in Fig. 15, the wire rods 11, 11 may be welded together by forming a welded portion 1c that spans the wire rods 11, 11 at the end 1a of the conductor wire 1. [Explanation of symbols]

[0047] 1 Conductor wire 1a end 1b Torsion joint (joint) 1c Welded section (joint) 11 Wire rod 2 Strip coil 31 Stator core 34 slots

Claims

1. A method for manufacturing a strip-shaped coil, the strip-shaped coil being formed into a long strip-like shape along the circumferential direction of the stator core by bending a conductor wire made of two or more wire rods housed in parallel in a slot of the stator core multiple times, and having both ends of the conductor wire disposed at one end in the longitudinal direction along the circumferential direction of the stator core, A method for manufacturing a strip-shaped coil, wherein the wire rods at at least one end of the conductor wire are joined together before bending the conductor wire.

2. The method for manufacturing a strip coil according to claim 1 , wherein the wires are joined by twisting.

3. The method for manufacturing a strip-shaped coil according to claim 2 , wherein the twist joint is performed by twisting the end of the conductor wire by 270° or more.

4. The method for manufacturing a strip coil according to any one of claims 1 to 3, wherein the one end of the conductor wire that joins the wire rods together is the end that is finally bent.

5. The method for manufacturing a strip-shaped coil according to any one of claims 1 to 3, wherein the wire is a rectangular wire.

6. A strip-shaped coil is formed in a long strip shape along the circumferential direction of the stator core by bending a conductor wire made of two or more wire rods housed in parallel in a slot of the stator core multiple times, and both ends of the conductor wire are disposed at one end in the longitudinal direction along the circumferential direction of the stator core, A strip-shaped coil having a joint at at least one end of the conductor wire where the wire rods are joined together.

7. The ribbon coil according to claim 6 , wherein the joints are twist joints.

8. The strip coil according to claim 7 , wherein the twisted joint is formed by twisting the end of the conductor wire by 270° or more.

9. The strip coil according to claim 7 or 8, wherein at least one of a twist angle and a twist direction of the twisted joints of the conductor wires is different for each phase.

10. The strip-shaped coil according to any one of claims 6 to 8, wherein the wire is a rectangular wire.

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