Method for processing coil wire and method for manufacturing coil wire
By using a beveled blade member to compress and cut the insulating coating, the method extends the insulation distance, addressing the short-circuit risk in stacked wires, ensuring secure electrical connections.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2024-11-22
- Publication Date
- 2026-06-03
AI Technical Summary
Existing methods for manufacturing rectangular wires risk insufficient insulation distance leading to short-circuits when wires are stacked, as the insulating coating is cut vertically, equalizing the insulation distance to the coating thickness.
A method involving a blade member with a beveled inner surface compresses and cuts the insulating coating perpendicular to the coil wire, forming a coating compression surface that extends the insulation distance beyond the coating thickness, followed by removing the uncompressed coating side.
This method effectively suppresses short-circuits by ensuring the insulation distance is longer than the coating thickness, preventing electrical contact between adjacent wires.
Smart Images
Figure 2026090824000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a method for processing a coil wire and a method for manufacturing a coil wire.
Background Art
[0002] Patent Document 1 discloses a method for manufacturing a rectangular wire that enables efficient removal of an insulating coating using a blade member by sandwiching a process of changing the shape of a conductor when removing the insulating coating covering the conductor in a rectangular wire.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the method for manufacturing a rectangular wire disclosed in Patent Document 1, the end of the rectangular wire is processed by cutting the insulating coating using a blade member and removing a part of the insulating coating. At this time, when the blade member cuts the insulating coating vertically, the distance in the direction perpendicular to the axial direction of the rectangular wire (insulation distance) from the surface of the insulating coating to the location where the insulating coating has been removed is equal to the thickness of the insulating coating. In this case, for example, when a plurality of such rectangular wires are stacked in an electromagnetic steel sheet, there is a risk that the insulation distance is insufficient and adjacent rectangular wires may short-circuit.
[0005] The present disclosure has been made in view of the above circumstances, and provides a method for processing a coil wire that makes the insulation distance longer than the thickness of the insulating coating at the processing location of the coil wire to suppress short-circuiting, and a method for manufacturing a coil wire using the method for processing a coil wire.
Means for Solving the Problems
[0006] A method for processing a coil wire according to one aspect of the present disclosure is A method for processing coil wires in a motor, in which a coil wire whose conductor is covered with an insulating coating is connected to another coil wire, by removing a portion of the insulating coating so that the coil wires can be connected to each other, A compression molding step in which a blade member having a beveled inner surface is pressed against the coil wire, the blade member cuts the insulating coating in a direction perpendicular to the axial direction of the coil wire, and the blade member compresses the conductor and the insulating coating with the bevel, thereby forming a coating compression surface on the coil wire, The method includes a coating removal step of removing the insulating coating on the side of the cut insulating coating that is not compressed by the slope.
[0007] A method for manufacturing a coil wire according to one aspect of this disclosure is: A method for manufacturing coil wires in which a portion of the insulating coating is removed so that the coil wires can be connected to each other when connecting coil wires with an insulating coating in a motor, A compression molding step in which a blade member having a beveled inner surface is pressed against the coil wire, the blade member cuts the insulating coating in a direction perpendicular to the axial direction of the coil wire, and the blade member compresses the conductor and the insulating coating with the bevel, thereby forming a coating compression surface on the coil wire, The method includes a coating removal step of removing the insulating coating on the side of the cut insulating coating that is not compressed by the slope. [Effects of the Invention]
[0008] According to this disclosure, a method for processing coil wires to suppress short circuits by making the insulation distance at the processing location of the coil wire longer than the thickness of the insulating coating, and a method for manufacturing coil wires using this processing method can be provided. [Brief explanation of the drawing]
[0009] [Figure 1](a) A schematic diagram of the coil wire processing method according to the present disclosure, before the compression molding step. (b) A schematic diagram of the coil wire processing method according to the present disclosure, during the compression molding step. (c) A schematic perspective view of the punch in the coil wire processing method according to the present disclosure. [Figure 2] This is a flowchart of a method for manufacturing a coil wire using the coil wire processing method according to the embodiment of this disclosure. [Figure 3] (a) A cross-sectional view parallel to the axial direction of the coil wire after the compression molding step in the coil wire processing method according to the embodiment of the present disclosure. (b) An enlarged view of Figure 4(a). (c) A cross-sectional view parallel to the axial direction of the coil wire when a general cutting member is used to cut the insulating coating. (d) An enlarged view of Figure 4(c). [Figure 4] (a) A graph showing the relationship between the relief angle and insulation distance of the blade member according to the embodiment of this disclosure. (b) A graph showing the relationship between the cutting edge R value and insulation distance of the blade member according to the embodiment of this disclosure. (c) Results showing the temperature of the coil wire and whether or not the insulating coating is broken according to the embodiment of this disclosure. [Figure 5] (a) A cross-sectional view parallel to the axial direction of the coil wire after the coating removal step in the coil wire processing method according to the embodiment of the present disclosure. (b) A cross-sectional view perpendicular to the axial direction of the coil wire after the coating removal step in the coil wire processing method according to the embodiment of the present disclosure. [Modes for carrying out the invention]
[0010] The following describes specific embodiments of this disclosure in detail with reference to the drawings. However, this disclosure is not limited to the following embodiments. Also, for clarity, the following descriptions and drawings have been simplified as appropriate.
[0011] <Structure of coil wire and punch> The coil wire according to this embodiment is used, for example, as a component of a motor. In this motor, the coil wires are connected to each other within an electromagnetic steel sheet. In order to connect the coil wires, it is necessary to remove the insulating coating surrounding the conductor of the coil wire around the connection point, thereby exposing a portion of the conductor. This embodiment discloses a technique for exposing a portion of the conductor of a coil wire used, for example, in such an application.
[0012] Figure 1(a) is a schematic diagram of the coil wire processing method according to the present disclosure before the compression molding step. Figure 1(b) is a schematic diagram of the coil wire processing method according to the present disclosure during the compression molding step. Figures 1(a) and 1(b) show cross-sections of the coil wire and the punch, respectively. Note that the right-handed xyz Cartesian coordinate system shown in Figure 1 is for convenience only, to illustrate the positional relationships of the components. In Figure 1, the x-axis represents the axial direction of the coil wire, and the positive z-axis is vertically upward. This is consistent across all drawings, including Figures 3 and 5, which will be discussed later.
[0013] The coil wire 1 consists of a conductor 11 and an insulating coating 12. The punch 2 consists of a main body member 21 and a blade member 22, the blade member 22 having an inner surface 221, an outer surface 222 and a tip portion 223.
[0014] The coil wire 1 is constructed by having an insulating coating 12 cover the entire side surface of the conductor 11. The coil wire 1 operates as a coil when current is passed through it after it has been wound in a spiral shape. The coil wire 1 is used, for example, in the stator coil of a motor mounted on an automobile, and its length and diameter are appropriately determined according to the application of the coil wire 1. In addition, the shape of the cross-section of the coil wire 1 perpendicular to the axial direction (cut surface by the yz plane) is square or rectangular.
[0015] The conductor 11 is a metal wire through which current flows when the coil wire 1 operates as a coil. The material of the conductor 11 is, for example, a metal such as copper or aluminum. The insulating film 12 serves to cover the side surface portion of the conductor 11 so that the conductors 11 do not short-circuit when the conductor 11 is used as a coil wire. The thickness of the insulating film 12 is, for example, about 0.16 mm, but is appropriately determined according to the size and use of the coil wire 1. The material of the insulating film 12 is, for example, a resin such as polyurethane or fluorine acrylic resin.
[0016] FIG. 1(c) is a schematic perspective view of a punch in the coil wire processing method according to an embodiment of the present disclosure. Here, FIG. 1(c) shows a schematic perspective view of the punch 2 disposed on the negative z-axis direction side in FIG. 1(a). The punch 2 sandwiches the coil wire 1 from the positive z-axis direction side and the negative z-axis direction side, and cuts the insulating film 12. The punch 2 operates, for example, when the main body member 21 receives a force from the outside.
[0017] The main body member 21 is a base of the punch 2 and is combined with the blade member 22. The material of the main body member 21 is, for example, an iron-based metal such as iron or carbon steel, or an alloy steel in which additive elements such as chromium, nickel, or tungsten are added to carbon steel. [[ID=!2]]
[0018] The blade member 22 comes into contact with the coil wire 1 as the punch 2 operates, and cuts the insulating film 12 at the tip portion 223. For this reason, the tip portion 223 has a so-called pin angle (pointed shape), and its blade angle is an acute angle. Here, the blade angle is typically about 75°, but may be 70° or more and 80° or less. The blade member 22 has an inner surface 221 inclined from the surface on the negative x-axis direction side toward the tip portion 223, and an outer surface 222 inclined from the surface on the positive x-axis direction side toward the tip portion 223. The material of the blade member 22 is, for example, tool steel such as carbon steel or die steel, or alloy steel in which chromium, molybdenum, vanadium, tungsten, cobalt, etc. are added to iron.
[0019] <Coil wire processing method> Next, referring to FIG. 2, the coil wire processing method according to an embodiment of the present disclosure will be described. FIG. 3 is a flowchart of a coil wire manufacturing method using the coil wire processing method according to an embodiment of the present disclosure.
[0020] First, as shown in Figure 1(a), the coil wire 1 is placed on the blade member 22 so that the tip portion 223 of the blade member 22 can be brought into contact with the coil wire 1 in step S2, which will be described later (step S1). The coil wire 1 may be fixed in place using, for example, a gripping device that grips the end of the coil wire 1.
[0021] Next, as shown in Figure 1(b), the blade member 22 compresses the coil wire 1, compressing the conductor 11 and the insulating coating 12 (step S2). Here, this compression molding is, in other words, crushing molding or pressing. In step S2, the tip portion 223 of the blade member 22 cuts the insulating coating 12 in a direction perpendicular to the axial direction of the coil wire 1.
[0022] Here, the inner surface 221 of the blade member 22 is inclined with respect to the axial direction of the coil wire 1. As the inner surface 221 is inclined with respect to the axial direction of the coil wire 1, the inner surface 221 compresses the conductor 11 and the insulating coating 12 in a direction perpendicular to the inner surface 221, as shown in Figure 1(b).
[0023] Figure 3(a) is a cross-sectional view parallel to the axial direction of the coil wire after the compression molding step in the coil wire processing method according to the present disclosure. Figure 3(b) is an enlarged view of Figure 3(a). In step S2, the insulating coating 12 remains on the surface of the coil wire 1 that is compressed by the inner surface 221 of the blade member 22, without the coating floating, and the insulating coating 12 remains so as to follow the compressed conductor 11. As a result, a coating compression surface 121 is formed on the coil wire 1 that is shaped along the inner surface 221 of the blade member 22 and has a depression angle equal to the inclination angle of the inner surface 221 with respect to the axial direction of the coil wire 1.
[0024] The coating compression surface 121 is formed by moving the insulating coating 12 inward from its original position relative to the coil wire 1. By forming the coating compression surface 121 on an inclined surface that intrudes inward towards the coil wire 1, the insulation distance of the coil wire 1 can be made longer than the thickness of the insulating coating 12, as shown in Figure 3(b). By extending the insulation distance, it is possible to suppress short circuits between coil wires 1 when multiple coil wires 1 are arranged side by side to form a coil.
[0025] On the other hand, as shown in Figures 3(c) and 3(d), when the insulating coating 12 is cut using a blade member of a general shape, the compression effect of the bevel on the coil wire 1 is not obtained, and the insulating coating 12 is cut without flowing. As a result, the thickness of the insulating coating 12 and the insulation distance become equal. Also, at the cut portion, a part of the insulating coating 12 separates from the conductor 11 and floats. For this reason, when a blade member of a general shape is used, the effect of this disclosure, which forms a coating compression surface 121 and makes the insulation distance longer than the thickness of the insulating coating 12, cannot be obtained.
[0026] Figure 4(a) is a graph showing the relationship between the relief angle of the blade member and the insulation distance according to the embodiment of this disclosure. Here, it is preferable that the insulation distance be 0.35 mm or more by the coil wire processing method shown in this disclosure. To obtain this effect, it is preferable that the inclination angle of the inner surface 221 with respect to the axial direction of the coil wire 1 is 60° or less, and more preferably 30° or less. That is, the relief angle of the blade member 22 shown in Figure 4(a) (the angle on the inner surface 221 side with respect to the direction in which the blade member 22 is pressed as the axis) is preferably 30° or more, and more preferably 60° or more. When the inclination angle of the inner surface 221 is 60° or less, that is, when the relief angle of the blade member 22 is 30° or more, the effect is obtained in step S2 that the inner surface 221 compresses the conductor 11 and forms a coating compression surface 121.
[0027] Figure 4(b) is a graph showing the relationship between the R value of the cutting edge of the blade member according to the embodiment of this disclosure and the insulation distance. Here, the R value is the radius (mm) of the sector that forms the roundness of the cutting edge. In order to make the insulation distance 0.35 mm or more, it is preferable that the R value of the tip portion 223 is 0.25 or less, and it is even more preferable that the cutting edge is sharp, i.e., the R value is 0. By making the R value of the tip portion 223 0.25 or less, the insulating coating 12 can be cut at a point closer to the tip of the blade member 22, making it possible to make the insulation distance longer.
[0028] Furthermore, steps S2 and S3, described later, are preferably performed by so-called warm forming. Figure 4(c) shows the changes in the insulating coating 12 on the xy plane and xz plane that occur when the cutting member 22 is brought into contact with the coil wire 1, which has a rectangular cross-sectional shape, from the positive z-axis side and the negative z-axis side. As shown in Figure 4(c), when the temperature of the coil wire is as low as 70°C, the insulating coating 12 on the xy plane breaks, and the insulation distance cannot be increased. For this reason, the temperature of the coil wire 1 in steps S2 and S3, described later, is preferably 90°C or higher, and more preferably 110°C or higher. By increasing the temperature of the coil wire 1, the flexibility of the insulating coating 12 covering the conductor 11 is improved, making it less likely for the insulating coating 12 to break on the slope formed by the inner surface 221.
[0029] Next, using a coating removal device (not shown), the insulating coating 12 on the side of the coil wire 1 where the coating compression surface 121 was not formed (the side that was in contact with the outer surface 222) is removed (step S3). Figure 5(a) is a cross-sectional view of the coil wire parallel to the axial direction after step S3 is performed. Figure 5(b) is a cross-sectional view of the coil wire perpendicular to the axial direction after step S3 is performed.
[0030] In step S3, the insulating coating 12 is removed only from the surfaces of the coil wire 1 that were pressed against the punch 2 in the positive z-axis direction and the surfaces in the negative z-axis direction. As a result, as shown in Figure 5(b), after the removal of the insulating coating 12, the ends of the coil wire 1 have the conductor 11 exposed only on the surfaces in the positive z-axis direction and the negative z-axis direction, while the surfaces in the positive y-axis direction and the negative y-axis direction are covered with the insulating coating 12. This processing has the effect of suppressing short circuits between coil wires 1 when multiple coil wires 1 are stacked in the z-axis direction, as the insulation distance is extended due to the formation of the coating compression surface 121. On the other hand, even when multiple coil wires 1 are arranged in the y-axis direction, the insulating coating 12 remaining on the surface of the coil wires 1 provides an insulating effect between the coil wires 1.
[0031] Furthermore, when performing step S3, it is preferable that the coating removal device removes a portion of the conductor 11 on the positive z-axis side and the negative z-axis side of the coil wire 1, as shown in Figure 5(a). This ensures that the insulation distance between the coil wires 1 is maintained when multiple coil wires 1 are stacked in the z-axis direction.
[0032] As described above, in the coil wire processing method according to the embodiment of this disclosure, a blade member having a beveled surface on its inner surface is pressed against the coil wire, thereby compressing the conductor and the insulating coating. The compression of the conductor and the insulating coating forms a coating compression surface on the coil wire having a depression angle equal to the bevel. This processing method makes it possible to provide a coil wire processing method that makes the insulation distance at the processed part of the coil wire longer than the thickness of the insulating coating and suppresses short circuits, and a coil wire manufacturing method using this coil wire processing method. [Explanation of Symbols]
[0033] 1. Coil wire 11 Conductors 12 Insulating coating 121 Coating compression surface 2 punches 21 Main body components 22 Blade Member 221 Inner surface 222 External surface 223 Tip
Claims
1. A method for processing coil wires in a motor, in which a coil wire whose conductor is covered with an insulating coating is connected to another coil wire, by removing a portion of the insulating coating so that the coil wires can be connected to each other, A compression molding step in which a blade member having a beveled inner surface is pressed against the coil wire, the blade member cuts the insulating coating in a direction perpendicular to the axial direction of the coil wire, and the blade member compresses the conductor and the insulating coating with the bevel, thereby forming a coating compression surface on the coil wire, The method includes a coating removal step of removing the insulating coating on the side of the cut insulating coating that is not compressed by the slope, Method for processing coil wire.
2. The inclined surface formed on the blade member has an inclination angle of 60° or less with respect to the axial direction of the coil wire. In the compression molding step, the inclined surface compresses the conductor and the insulating coating so that the coating compression surface has a downward angle equal to the inclination angle with respect to the axial direction of the coil wire. The method for processing a coil wire according to claim 1.
3. In the compression molding step and the coating removal step, the temperature of the coil wire is 90°C or higher. The method for processing a coil wire according to claim 1.
4. The blade member has the inner surface extending over the entire circumference of the coil wire, In the compression molding step, the inclined surface formed on the inner surface causes the coating compression surface to be formed over the entire circumference of the coil wire. A method for processing a coil wire according to any one of claims 1 to 3.
5. A method for manufacturing coil wires in which a portion of the insulating coating is removed so that the coil wires can be connected to each other when connecting coil wires with an insulating coating in a motor, A compression molding step in which a blade member having a beveled inner surface is pressed against the coil wire, the blade member cuts the insulating coating in a direction perpendicular to the axial direction of the coil wire, and the blade member compresses the conductor and the insulating coating with the bevel, thereby forming a coating compression surface on the coil wire, The method includes a coating removal step of removing the insulating coating on the side of the cut insulating coating that is not compressed by the slope, A method for manufacturing coil wire.