Press mold, method for manufacturing terminal-attached electric wire, and terminal-attached electric wire

Abstract

In a press mold including a lower mold and an upper mold for crimping a crimp forming portion of a crimp terminal to an electric wire, for example, a lower mold center convex portion of a lower mold indentation portion provided in the lower mold has a tip surface and front and rear wall surfaces positioned opposite to each other in a length direction. For example, when an edge where the front wall surface contacts the tip surface is defined as a first edge, and an angle of inclination of the front wall surface with respect to a vertical axis derived from the first edge is defined as an indentation angle, the indentation angle is within a range of 20 DEG to 30 DEG.

Description

Technical Field

[0001] The present invention relates to a molding die, a method for manufacturing a terminal-attached electric wire, and the terminal-attached electric wire. Background Art

[0002] Conventionally, there is a terminal crimping device for producing a terminal-attached electric wire by crimping a crimping forming portion of a crimping terminal onto the end of the electric wire. Typically, a terminal crimping device uses a press die comprising a lower die and an upper die. The lower die and the upper die are held so that they can move vertically toward and away from each other. When the lower die and the upper die approach each other, the crimping portion is plastically deformed to form the crimping portion.

[0003] Patent document JP 2022-42683A discloses a technology related to a press mold, which includes a lower mold and an upper mold, each of which has a protruding indentation that contacts a crimping forming portion, a concave portion on one side of the width direction adjacent to the indentation, and a convex portion on the other side of the width direction adjacent to the indentation. Here, the width direction is a direction perpendicular to the longitudinal direction consistent with the axial direction of the crimping forming portion. When the lower mold and the upper mold of the press mold are brought close to each other with the crimping forming portion placed on the indentation of the lower mold, the convex portion of the lower mold engages with the concave portion of the upper mold, and the convex portion of the upper mold engages with the concave portion of the lower mold. Then, the indentation of the lower mold and the indentation of the upper mold, while being clamped between the convex portions located at both ends in the width direction, form a crimping portion by pressing the crimping forming portion. Therefore, the convex portion limits the plastic deformation of the crimping forming portion caused by expansion in the width direction, preventing the crimping terminal from fitting into the press mold and preventing burrs from appearing in the crimping portion. Summary of the Invention

[0004] Since the conditions regarding the shape of the swaging die disclosed in JP 2022-42683A are actually unknown, a specific proposal is desired in order to improve the electrical performance of terminal-attached electric wires manufactured using the swaging die.

[0005] An object of the present invention is to provide a swaging die for improving the electrical properties of a terminal-fitted electric wire, a method for manufacturing a terminal-fitted electric wire having improved electrical properties, or a terminal-fitted electric wire.

[0006] One embodiment of the present invention is a molding die, which includes a lower die and an upper die, and the lower die and the upper die are used to crimp the crimping forming portion of the crimping terminal to the wire when the lower die and the upper die are close to each other in the vertical direction, wherein the lower die and the upper die both have the shape of a rectangular parallelepiped, the cross-section on the horizontal plane of the rectangular parallelepiped is limited in the length direction consistent with the axial direction of the crimping forming portion and in the width direction perpendicular to the length direction, and the lower die and the upper die each include: a retracted portion, which is arranged in a concave portion and has a central convex portion protruding in the crimping direction, the concave portion is formed on the die surface facing the crimping direction and contacts the crimping forming portion along the length direction; a concave portion, which is adjacent to one end of the retracted portion in the width direction, and Extending from the mold surface in a direction opposite to the crimping direction; and a convex portion, which is adjacent to the other end of the indentation portion in the width direction and protrudes from the mold surface in the crimping direction, the central convex portion of the indentation portion includes an end surface and a front wall surface and a rear wall surface positioned opposite to each other in the length direction, wherein, when the end edge where the front wall surface meets the end surface is defined as a first end edge, and the end edge where the rear wall surface meets the end surface is defined as a second end edge; and when the inclination angle of the front wall surface relative to the vertical axis originating from the first end edge and the inclination angle of the rear wall surface relative to the vertical axis originating from the second end edge are respectively defined as indentation angles, the indentation angle is within a range of greater than 20° and less than 30°.

[0007] Furthermore, according to one aspect of the present invention, a method for manufacturing a terminal-attached electric wire in which a crimping portion of a crimp terminal is crimped to the electric wire comprises: inserting a portion of the electric wire into the crimping portion; and clamping the crimping portion, into which the portion of the electric wire is inserted, by a press die including a lower die and an upper die. The press die is the press die according to the aforementioned aspect.

[0008] Furthermore, an electric wire to which a terminal is attached according to an embodiment of the present invention includes a crimping portion formed by clamping a crimping forming portion into which a portion of the electric wire is inserted by a die press mold including a lower die and an upper die, wherein the crimping portion has a lower crimping recess and an upper crimping recess, a convex shape of a portion of the lower die is transferred to the lower crimping recess, and a convex shape of a portion of the upper die is transferred to the upper crimping recess, each of the lower crimping recess and the upper crimping recess having a bottom surface and an axial direction relative to the crimping forming portion. The front inner wall surface and the rear inner wall surface are positioned opposite to each other in a consistent length direction, when the corner where the front inner wall surface meets the bottom surface is defined as a first corner, and the corner where the rear inner wall surface meets the bottom surface is defined as a second corner, and when the inclination angle of the front inner wall surface relative to the vertical axis originating from the first corner and the inclination angle of the rear inner wall surface relative to the vertical axis originating from the second corner are defined as a recess angle, the recess angle is within a range of greater than 20° and less than 30°.

[0009] According to the present invention, it is possible to provide a swaging die that improves the electrical properties of a terminal-fitted electric wire, a method for manufacturing a terminal-fitted electric wire having improved electrical properties, or a terminal-fitted electric wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 FIG. 1 is a perspective view of a terminal crimping device to which a swaging die according to an embodiment can be applied.

[0011] Figure 2 is a perspective view of a terminal-attached electric wire manufactured using a swaging die according to one embodiment.

[0012] Figure 3 This is a perspective view showing an electric wire and a crimping terminal before being mounted on a terminal crimping device.

[0013] Figure 4 is a perspective view of a coining die according to one embodiment.

[0014] Figure 5 is a perspective view of a lower mold constituting a swaging mold according to one embodiment.

[0015] Figure 6 is a partial cross-sectional view showing a state of the lower mold and the upper mold before they approach each other.

[0016] Figure 7 It is a partial cross-sectional view showing the state of the lower mold and the upper mold during crimping.

[0017] Figure 8 It is a partial cross-sectional view showing a state where the lower mold and the upper mold are separated.

[0018] Figure 9 corresponds to Figure 5 Partial cross-sectional view of the lower die at section IX-IX.

[0019] Figure 10 is with Figure 2 The XX section corresponds to a partial cross-sectional view of the electric wire with the terminal attached.

[0020] Figure 11 is a graph showing the electrical properties of Example 1 of the terminal-attached electric wire.

[0021] Figure 12 is a graph showing the electrical properties of Example 2 of the terminal-attached electric wire.

[0022] Figure 13 is a graph showing the electrical properties of Example 3 of the terminal-attached electric wire. DETAILED DESCRIPTION

[0023] Hereinafter, a swaging die, a method for manufacturing a terminal-attached electric wire, and a terminal-attached electric wire according to an embodiment will be described in detail with reference to the accompanying drawings. For convenience of explanation, the dimensional ratios in the drawings are exaggerated and may differ from the actual ratios.

[0024] Figure 1 1 is a perspective view of a terminal crimping device 1 that can employ a die pressing mold 10 according to one embodiment. Hereinafter, as an example, the directions of the terminal crimping device 1 and the die pressing mold 10 will be defined as follows: the X direction represents the length direction from the rear side to the front side of the crimping terminal 110, which is aligned with the axial direction of the crimping terminal 110 mounted on the die pressing mold 10; the Y direction represents the width direction perpendicular to the X direction on a horizontal plane; and the Z direction represents the vertical direction from the lower side to the upper side. The terms "front" and "rear" may be used for the X direction. In addition, the terms "upper" and "lower" may be used for the Z direction.

[0025] Figure 2 is a perspective view of a terminal-attached electric wire 100 according to one embodiment manufactured using a swaging die 10 . Figure 3 1 is a perspective view showing the electric wire 101 and the crimping terminal 110 before being mounted on the terminal crimping device 1 .

[0026] The terminal crimping device 1 manufactures the terminal-attached electric wire 100 by crimping the crimp forming portion 112 of the crimping terminal 110 to the end portion of the electric wire 101 to form the crimping portion 114 .

[0027] The electric wire 101 may be a high-voltage electric wire used in a high-voltage circuit of an electric vehicle or the like. The electric wire 101 has a core wire 102 and a sheath 103 covering the core wire 102. The core wire 102 is, for example, a stranded wire including a plurality of single wires made of soft copper. In the following corresponding drawings, for convenience, the core wire 102 is shown as a cross section of one conductor. The sheath 103 is an insulating member including a synthetic resin such as polyethylene. Figure 3 As shown, before the electric wire 101 is mounted on the terminal crimping device 1 , the coating portion 103 is stripped off at the end portion of the electric wire 101 , and a portion of the core wire 102 is exposed to the outside.

[0028] As described above, the crimping terminal 110 is a metal terminal that is crimped to the end of the wire 101, specifically, to the core wire 102, which has been exposed after the sheath 103 has been stripped away. The crimping terminal 110 can be made of, for example, pure copper with a copper content of 99.90% or greater, and may be further silver-plated. The pure copper may be oxygen-free copper, tough pitch copper, phosphorus-deoxidized copper, or the like. The crimping terminal 110 is generally rod-shaped and has a connecting portion 111, a crimping forming portion 112, and a flange 113.

[0029] The connection portion 111 is illustratively a cylindrical portion located on the front side of the crimping terminal 110 in the X direction along the axial direction of the crimping terminal 110. The connection portion 111 is connected to a counterpart connection portion of a counterpart terminal so that the crimping terminal 110 is electrically connected to the counterpart terminal.

[0030] The crimping forming portion 112 is a cylindrical portion located behind the flange 113 in the X direction on the crimping terminal 110. The crimping forming portion 112 has an insertion hole 112a extending in the axial direction of the crimping forming portion 112, and the end of the core wire 102 is inserted into the insertion hole 112a. In other words, the crimping terminal 110 used in this embodiment is a closed barrel type.

[0031] The flange 113 is a cylindrical portion located between the connection portion 111 and the crimping forming portion 112 and protrudes radially outward from the outer circumference of the crimping forming portion 112. An annular groove 113a to which a sealing member can be freely attached may be formed on the outer circumference of the flange 113.

[0032] The terminal crimping device 1 includes a base 11, a wire holder 12, a frame 13, a lower die 14, a movement regulating portion 15, an upper die 16, and a driving tool (not shown). The lower die 14 and the upper die 16 constitute a press die 10 according to the present embodiment.

[0033] The base 11 is a block-shaped structure such as a rectangular parallelepiped, and is fixed to a workbench on which the terminal crimping device 1 is placed.

[0034] The wire holder 12 includes a first holder 12a, which is fixed to the base 11 and on which the wire 101 is placed; and a second holder 12b, which is configured to be able to approach and separate from the first holder 12a in the Z direction and is capable of holding the wire 101 placed on the first holder 12a. The first holder 12a has a groove 12c located in the center in the Y direction and extending in the X direction. The wire 101 is arranged in the groove 12c, so that the first holder 12a restricts movement of the wire 101 in the Y direction. With the second holder 12b separated from the first holder 12a in the Z direction, the wire holder 12 first places the wire 101 on the first holder 12a. Thereafter, the wire holder 12 moves the second holder 12b closer to the first holder 12a in the Z direction, ultimately holding the wire 101 between the first and second holders 12a, 12b. When the electric wire 101 is held between the first holding member 12 a and the second holding member 12 b , movement of the electric wire 101 in the X, Y, or Z direction is restricted.

[0035] The frame 13 is fixed to the base 11 and has a frame main body 13 a and a frame support 13 b that supports the upper mold 16 movably in the Z direction relative to the frame main body 13 a .

[0036] Figure 4 This is a perspective view of the embossing die 10 at an angle at which the front side of the embossing die 10 in the X direction can be visually recognized. Figure 4 The swaging die 10 is shown in a state where the crimping forming portion 112 of the crimping terminal 110 is placed on the lower die 14 and the crimping forming portion 112 is not yet held between the lower die 14 and the upper die 16 . Figure 5 This is a perspective view of the lower mold 14 at an angle at which the front side of the lower mold 14 in the X direction can be visually recognized.

[0037] The lower die 14 of the embossing die 10 is supported by the base 11 and forms a pair of dies with the upper die 16 for holding and pressing the crimping forming portion 112. The lower die 14 can be called an "anvil." The lower die 14 has a lower die body 20 and a lower die concave portion 21.

[0038] The lower mold body 20 is a rectangular parallelepiped block, and its horizontal cross section is defined in the X direction and the Y direction. The lower mold body 20 has a lower mold surface 20a. The lower mold surface 20a is the mold surface of the lower mold 14, which faces the upper mold 16 and is close to the upper mold surface 30a (see FIG. 2 ) when the lower mold 14 and the upper mold 16 are combined. Figure 6 ).

[0039] The lower mold recess 21 is located at the center of the lower mold surface 20a of the lower mold body 20 in the Y direction and is formed as a groove in the X direction. The lower mold recess 21 has a lower mold bottom surface 21a whose width in the Y direction is set to be smaller than the width of the opening in the Y direction of the opening surface opening at the lower mold surface 20a. Furthermore, the lower mold recess 21 has a first inclined side surface 21b and a second inclined side surface 21c formed symmetrically in the Y direction, originating from the lower mold bottom surface 21a. One end of the first inclined side surface 21b is continuous with one end of the lower mold bottom surface 21a extending in the X direction, and the other end of the first inclined side surface 21b is continuous with the lower mold surface 20a. Similarly, one end of the second inclined side surface 21c is continuous with the other end of the lower mold bottom surface 21a extending in the X direction, and the other end of the second inclined side surface 21c is continuous with the lower mold surface 20a. The first and second inclined side surfaces 21b and 21c are inclined away from each other in the Y direction as they move from the lower mold bottom surface 21a to the lower mold surface 20a. The lower mold concave portion 21 has a lower mold setback 22 provided on the lower mold 14.

[0040] The crimping forming portion 112 is placed on the lower die setback 22 located on the lower die bottom surface 21a. The lower die setback 22 crimps the crimping forming portion 112 located at the end of the electric wire 101, thereby transferring the shape of the lower die setback 22 to the crimping portion 114 to form the lower crimping portion 114a of the crimping portion 114 (see FIG. Figure 7 and Figure 8 ). The lower mold indentation portion 22 includes a lower mold central protrusion 22a and a pair of lower mold indentation bottom surfaces 22b. The lower mold central protrusion 22a protruding in the crimping direction is lower than the lower mold surface 20a in the Z direction and is located in the center of the lower mold body 20 in the Y direction. Here, the crimping direction relative to the lower mold 14 is the direction from the lower side to the upper side in the Z direction. The lower mold indentation bottom surfaces 22b are located on both sides of the lower mold central protrusion 22a in the Y direction and are formed below the lower mold central protrusion 22a in the Z direction. One lower mold indentation bottom surface 22b is continuous with the first inclined side surface 21b. The other lower mold indentation bottom surface 22b is continuous with the second inclined side surface 21c.

[0041] Hereinafter, the width of the lower mold central convex portion 22a in the Y direction is defined as a setback width W. The height in the Z direction from the lower mold setback bottom surface 22b to the distal end surface 22c of the lower mold central convex portion 22a is defined as a setback height H.

[0042] The lower mold 14 includes a lower mold concave portion 23 and a lower mold convex portion 24. The lower mold concave portion 23 and the lower mold convex portion 24 are adjacent to each other in the Y direction via the lower mold concave portion 21 including the lower mold setback portion 22.

[0043] The lower mold concave portion 23 is formed adjacent to one end of the lower mold setback portion 22 across the first inclined side surface 21b in the Y direction and is formed downward from the lower mold surface 20a in the Z direction. The lower mold concave portion 23 has a bottom surface 23a (see FIG. Figure 6 ), and further having a first inner surface 23b and a second inner surface 23c facing each other in the Y direction (see Figure 6 ) and the third inner surface 23d ( Figure 6 Here, among the multiple inner surfaces forming the lower die concave portion 23, the first inner surface 23b is closest to the lower die retracted portion 22.

[0044] The lower die protrusion 24 is adjacent to the other end of the lower die setback 22 in the Y direction across the second inclined side surface 21c, and protrudes upward from the lower die surface 20a in the Z direction. Note that the lower die protrusion 24 can be regarded as a wall standing upright on the right side of the lower die setback 22, and can therefore be called a "horizontal wall" or "pillar". The lower die protrusion 24 has an end surface 24a, and also has a first outer surface 24b and a second outer surface 24c facing each other in the Y direction (see FIG. Figure 6 ) and a third outer surface 24d and a fourth outer surface 24e facing each other in the X direction. Here, among the plurality of outer surfaces forming the lower die protrusion 24, the first outer surface 24b is closest to the lower die recessed portion 22.

[0045] like Figure 1 As shown, the movement regulating portion 15 is located on the front side in the X direction of the lower mold 14. The movement regulating portion 15 has a regulating portion body 15a and a pair of flange receiving portions 15b.

[0046] The regulating portion body 15a is, for example, a rectangular block. A pair of flange receiving portions 15b protrude upward from the upper surface of the regulating portion body 15a and are spaced apart in the Y direction. When the connecting portion 111 of the crimping terminal 110 is inserted between one flange receiving portion 15b and the other flange receiving portion 15b, the movement of the crimping terminal 110 in the Y direction is restricted. When the crimping forming portion 112 is arranged on the lower mold retracted portion 22, the flange 113 of the crimping forming portion 112 contacts the pair of flange receiving portions 15b in the X direction, thereby restricting the movement of the crimping terminal 110 toward the front in the X direction.

[0047] The upper die 16 of the die pressing mold 10 is supported by the frame 13. The upper die 16 can be called a "crimp". The upper die 16 is supported by the frame support 13b and faces the lower die 14 in the Z direction. In addition, the upper die 16 is moved close to the lower die 14 or separated from the lower die 14 by moving the frame support 13b relative to the frame body 13a in the Z direction. Here, the crimping direction relative to the upper die 16 is the direction from the upper side to the lower side in the Z direction. The upper die 16 has a shape obtained by rotating the lower die 14 180° while maintaining an orientation parallel to the YZ plane. In other words, the shape of the upper die 16 is substantially the same as that of the lower die 14. However, there may be differences between the lower die 14 and the upper die 16 in aspects such as the length in the Z direction.

[0048] The upper mold 16 has an upper mold body 30 and an upper mold concave portion 31. The end of the upper mold body 30 has the same shape as the end of the lower mold body 20, and the length of the upper mold body 30 in the Z direction is greater than the length of the lower mold body 20 in the Z direction. The mold surface of the upper mold body 30 is the upper mold surface 30a. The upper mold concave portion 31, which has the same shape as the lower mold concave portion 21, has an upper mold bottom surface and faces the lower mold concave portion 21 in the Z direction. The upper mold indentation 32 (see Figure 6 ) has the same shape as the lower die setback 22 and faces the lower die setback 22 in the Z direction. The upper die setback 32 crimps the crimping forming portion 112 located at the end of the electric wire 101, thereby transferring the shape of the upper die setback 32 to the crimping portion 114 to form the upper crimping portion 114b of the crimping portion 114 (see Figure 7 and Figure 8 The upper mold retracted portion 32 includes an upper mold central protrusion 32a and a pair of upper mold retracted bottom surfaces 32b. One upper mold retracted bottom surface 32b is continuous with the first inclined side surface 31b. The other upper mold retracted bottom surface 32b is continuous with the second inclined side surface 31c.

[0049] In addition, the upper die 16 has an upper die recess 33 (see Figure 6 ) and an upper die projection 34. The upper die recess 33 has the same shape as the lower die recess 23 and engages with the lower die projection 24 when approaching the lower die 14. The upper die projection 34 has the same shape as the lower die projection 24 and engages with the lower die recess 23 when approaching the lower die 14. Note that, like the lower die projection 24, the upper die projection 34 is regarded as a wall standing upright on the front side of the upper die setback 32, and can therefore be called a "horizontal wall" or "pillar."

[0050] Furthermore, the driving tool moves the frame support 13 b relative to the frame main body 13 a in the Z direction, thereby moving the upper mold 16 closer to and away from the lower mold 14 in the Z direction.

[0051] Next, a description will be given of steps for manufacturing the terminal-attached electric wire 100 by the terminal crimping device 1 including the swaging die 10 .

[0052] Figure 6 is with Figure 1 The VI-VI section in FIG. 1 corresponds to a cross-sectional view of the die 10. Specifically, Figure 6 It is a partial cross-sectional view showing the state of the lower mold 14 and the upper mold 16 before the crimping forming portion 112 of the crimping terminal 110 has been placed on the lower mold retracted portion 22 of the lower mold 14 and the crimping forming portion 112 has been crimped to the electric wire 101, that is, before the lower mold 14 and the upper mold 16 are brought close to each other.

[0053] Figure 7 is a partial cross-sectional view showing the state of the lower mold 14 and the upper mold 16, wherein the upper mold 16 is Figure 6 The illustrated state is close to the lower die 14 , and then the crimp forming portion 112 is pressed to form the crimping portion 114 .

[0054] Figure 8 It is shown in Figure 7 The illustrated state is a partial cross-sectional view of a state in which the finally formed crimping portion 114 is located on the lower die setback 22 of the lower die 14 after the upper die 16 and the lower die 14 are separated.

[0055] First, a step is performed in the terminal crimping device 1 to insert a portion of the electric wire 101 into the crimping forming portion 112. Specifically, the crimping terminal 110 is mounted in a predetermined position in the terminal crimping device 1, with the crimping forming portion 112 positioned on the lower die recess 22. Next, the electric wire 101 is placed on the first retaining member 12a of the electric wire retaining member 12, and then the core wire 102 of the electric wire 101 is inserted into the insertion hole 112a of the crimping forming portion 112. Next, the second retaining member 12b is brought close to the first retaining member 12a, so that the electric wire 101 is held between the first retaining member 12a and the second retaining member 12b. Figure 6 The state of the pressure-bonding forming portion 112 at this stage is shown in FIG.

[0056] Next, the step of crimping the crimping forming portion 112 to the electric wire 101 is performed in the terminal crimping device 1. Specifically, the terminal crimping device 1 moves the upper die 16 toward the lower die 14 by driving the driving tool. By this operation, as shown in FIG. Figure 7As shown, the upper mold 16 is brought close to the lower mold 14, and the crimping forming portion 112 is pressed (compressed) by being held between the lower mold indentation 22 and the upper mold indentation 32. At this time, the crimping forming portion 112 is compressed in the Z direction while extending in the Y direction, and finally, the shapes of the lower mold indentation 22 and the upper mold indentation 32 are transferred to the crimping terminal 110 to form the crimping portion 114. In this way, the terminal crimping device 1 crimps the core wire 102 inserted into the insertion hole 112a of the crimping terminal 110 with the crimping forming portion 112, thereby producing a terminal as shown in FIG. Figure 2 The illustrated crimp terminal 110 and the electric wire 101 are integrated into a terminal-attached electric wire 100 .

[0057] Thereafter, the terminal crimping device 1 drives the driving tool again to move the upper die 16 away from the lower die 14. By this operation, as shown in FIG. Figure 8 As shown, the upper die 16 and the lower die 14 are separated from each other, and the terminal-attached electric wire 100 can be taken out from the lower die 14 .

[0058] Next, the setting of the setback angle will be described, which is one factor that determines the shapes of the lower die setback 22 and the upper die setback 32. Here, since the shape of the lower die setback 22 and the shape of the upper die setback 32 are the same, the following description will focus on the setting of the lower die setback 22.

[0059] Figure 9 corresponds to Figure 5 A partial cross-sectional view of the lower die 14 at section IX-IX. Figure 9 The cross section in φ is a virtual XZ plane passing through the middle position of the lower mold setback 22 in the width direction corresponding to the Y direction of the lower mold 14 .

[0060] First, in the longitudinal direction corresponding to the X-direction of the lower mold 14, the width of the lower mold body 20 is defined as a first width W1, and the width of the lower mold protrusion 24 is defined as a second width W2. Second width W2 is shorter than first width W1. Similarly, in this longitudinal direction, the length of the end surface 22c of the lower mold center protrusion 22a of the lower mold setback 22 is defined as a setback length L. The lower mold setback 22 is arranged within the range defined by the second width W2 in the longitudinal direction. In other words, the setback length L is shorter than the second width W2.

[0061] The lower mold setback 22 has a front wall surface 22d and a rear wall surface 22e as longitudinally opposed wall portions. The front wall surface 22d and the rear wall surface 22e are inclined so that the longitudinal distance between them gradually increases as they move from the distal end surface 22c of the lower mold central protrusion 22a toward the lower mold bottom surface 21a. Here, the edge where the front wall surface 22d meets the distal end surface 22c is defined as a first edge 22f, and the edge where the rear wall surface 22e meets the distal end surface 22c is defined as a second edge 22g. The inclination angles of the front wall surface 22d from the first edge 22f and the inclination angle of the rear wall surface 22e from the second edge 22g relative to the vertical axis AX are respectively defined as setback angles θ1.

[0062] Figure 10 is with Figure 2 The XX section in FIG. 1 corresponds to a partial cross-sectional view of the electric wire 100 with the terminal attached. Specifically, Figure 10 1 is a cross-sectional view of the crimping portion 114 and its surroundings in the terminal-attached electric wire 100 . Figure 10 The cross section in is an imaginary XZ plane passing through the central axis of the crimping terminal 110 .

[0063] In crimping portion 114, the shape of lower die setback 22 is transferred to form lower crimping portion 114a, and the shape of upper die setback 32 is transferred to form upper crimping portion 114b. Lower die central protrusion 22a abuts a portion of lower crimping portion 114a, causing this portion to be significantly recessed to form lower crimping recess 114c. Similarly, a portion of upper crimping portion 114b is abutted by upper die central protrusion 32a and significantly recessed to form upper crimping recess 114d.

[0064] Furthermore, each of the lower and upper crimping recesses 114c and 114d has a bottom surface 114e, as well as a front inner wall surface 114f and a rear inner wall surface 114g, which are positioned opposite each other in the longitudinal direction. The front inner wall surface 114f and the rear inner wall surface 114g are inclined so that the distance between them in the longitudinal direction gradually narrows as they move from the main surface of the lower or upper crimping portion 114a or 114b toward the bottom surface 114e. Here, the corner where the front inner wall surface 114f meets the bottom surface 114e is defined as a first corner 114h, and the corner where the rear inner wall surface 114g meets the bottom surface 114e is defined as a second corner 114i. Furthermore, the inclination angles of the front inner wall surface 114f and the rear inner wall surface 114g relative to the vertical axis AX originating from the first corner 114h and the second corner 114i are each defined as a recess angle θ2.

[0065] In the crimping portion 114 , the core wire 102 , which is a bundle of multiple single wires, is held between the lower crimping portion 114 a and the upper crimping portion 114 b and is pressed into the insertion hole 112 a , so that the core wire 102 is in close contact with the crimping terminal 110 , thereby ensuring a conductive path.

[0066] Figure 11 : is a graph showing the ratio of the voltage drop at the crimping portion 114 to the retraction angle θ1 as the electrical performance of the terminal-attached electric wire 100 in Example 1. Figure 11 In FIG. 1 , the horizontal axis represents the retraction angle θ1 (degrees), and the vertical axis represents the ratio when the voltage drop is 1.0 when the retraction angle θ1 is 20°. Under the following various conditions, the voltage drop at the crimping portion 114 is measured by changing the retraction angle θ1, and the values ​​are obtained. Figure 11 The measurement results are shown.

[0067] The electric wire 101 in Example 1 has a core wire 102 including a plurality of wires made of soft copper and having a wire diameter of φ0.32 mm. The conductor size of the core wire 102 is 40 sq (conductor cross-sectional area: 39.73 mm 2 ).

[0068] The main material of the crimping terminal 110 in Example 1 is oxygen-free copper. The crimping terminal 110 is subjected to copper / silver plating as a base, and further subjected to silver plating. The thickness of the crimping forming portion 112 is 2.2 mm.

[0069] Furthermore, in the lower die 14 and the upper die 16 used to manufacture the terminal-attached electric wire 100 in Example 1, the conditions related to the shapes of the lower die setback portion 22 and the upper die setback portion 32 as setback portions are as follows: the setback length L is 8.0 mm; the setback width W is 3.0 mm; and the setback height H is 2.0 mm.

[0070] First, as a result of the first measurement in Example 1, when the setback angle θ1 was 20°, that is, when the recess angle θ2 at the crimping portion 114 was approximately 20°, the voltage drop was judged to be within the acceptable range of the electrical performance of the terminal-attached electric wire 100. Here, the lower the voltage drop ratio is compared to 1.0, the better the electrical performance is judged to be, and the higher the voltage drop ratio is compared to 1.0, the worse the electrical performance is judged to be.

[0071] Furthermore, as a result of the second measurement in Example 1, when the setback angle θ1 was 30°, that is, when the recess angle θ2 at the crimping portion 114 was approximately 30°, the voltage drop ratio was 0.9. This ratio was lower than 1.0, and the electrical performance of the terminal-attached electric wire 100 was judged to be good.

[0072] Furthermore, as a result of the third measurement in Example 1, when the retraction angle θ1 was 45°, that is, when the recess angle θ2 at the crimping portion 114 was approximately 45°, the voltage drop ratio was 1.7. This ratio was greater than 1.0, and it was judged that the electrical performance of the terminal-attached electric wire 100 was poor.

[0073] Therefore, for the electrical performance of the terminal-attached electric wire 100 in Example 1, it is desirable that the setback angle θ1 is within the range of 20° or more and 30° or less with respect to the voltage drop in the crimping portion 114 .

[0074] Figure 12 : is a graph showing the ratio of the voltage drop at the crimping portion 114 to the retraction angle θ1 as the electrical performance of the terminal-attached electric wire 100 in Example 2. Figure 12 In FIG, the horizontal axis represents the retraction angle θ1 (degrees), and the vertical axis represents the ratio of the voltage drop. Figure 11 Under the same conditions as in Example 1 shown, the voltage drop when the retraction angle θ1 is 20° is 1.0. Under the following various conditions, the voltage drop at the crimping portion 114 is measured by setting the retraction angle θ1 to 20°, and the voltage drop is obtained. Figure 12 The measurement results are shown.

[0075] The electric wire 101 in Example 2 has a core wire 102 including a plurality of wires made of soft copper and having a diameter of φ0.32 mm. The conductor size of the core wire 102 is 95 sq (conductor cross-sectional area: 96.27 mm 2 ).

[0076] The main material of the crimping terminal 110 in Example 2 is tough pitch copper. The crimping terminal 110 is subjected to copper / silver plating as a base, and further subjected to silver plating. The thickness of the crimping forming portion 112 is 2.0 mm.

[0077] In the lower die 14 and the upper die 16 used to manufacture the terminal-attached electric wire 100 in Example 2, the conditions related to the shapes of the lower die setback portion 22 and the upper die setback portion 32 as the setback portions are as follows: the setback length L is 11.60 mm; the setback width W is 3.95 mm; and the setback height H is 2.55 mm.

[0078] As a result of the measurement in Example 2, when the retraction angle θ1 was 20°, that is, when the recess angle θ2 at the crimping portion 114 was approximately 20°, the voltage drop ratio was 0.09. This ratio was lower than 1.0 in Example 1, and it was determined that the electrical performance of the terminal-attached electric wire 100 was good.

[0079] Therefore, regarding the voltage drop at the crimping portion 114 , the electrical performance of the terminal-attached electric wire 100 in Example 2 satisfies the condition assumed in Example 1: the retraction angle θ1 is preferably within the range of 20° or more and 30° or less.

[0080] Figure 13 : is a graph showing the ratio of the voltage drop at the crimping portion 114 to the retraction angle θ1 as the electrical performance of the terminal-attached electric wire 100 in Example 3. Figure 13 In FIG, the horizontal axis represents the retraction angle θ1 (degrees), and the vertical axis represents the ratio of the voltage drop. Figure 11 Under the same conditions as in Example 1 shown, the voltage drop when the retraction angle θ1 is 20° is 1.0. Under the following various conditions, the voltage drop at the crimping portion 114 is measured by setting the retraction angle θ1 to 20°, and the voltage drop is obtained. Figure 13 The measurement results are shown.

[0081] The electric wire 101 in Example 3 has a core wire 102 including a plurality of single wires made of soft copper and having a diameter of φ0.80 mm. The conductor size of the core wire 102 is 40 sq.

[0082] Note that the crimping terminal 110 in Example 3 is the same as the crimping terminal 110 in Example 1. Furthermore, the lower die 14 and the upper die 16 used to manufacture the terminal-attached electric wire 100 in Example 3 are the same as the lower die 14 and the upper die 16 used to manufacture the terminal-attached electric wire 100 in Example 1.

[0083] As a result of the measurement in Example 3, when the retraction angle θ1 was 20°, that is, when the recess angle θ2 at the crimping portion 114 was approximately 20°, the voltage drop ratio was 0.08. This ratio was lower than 1.0 in Example 1, and it was determined that the electrical performance of the terminal-attached electric wire 100 was good.

[0084] Therefore, regarding the voltage drop at the crimping portion 114 , the electrical performance of the terminal-attached electric wire 100 in Example 3 satisfies the condition assumed in Example 1: the retraction angle θ1 is preferably within the range of 20° or more and 30° or less.

[0085] Next, the swaging die 10 , a method of manufacturing the terminal-attached electric wire 100 , and effects of the terminal-attached electric wire 100 will be described.

[0086] The press mold 10 according to the present embodiment includes a lower mold 14 and an upper mold 16 for crimping the crimping forming portion 112 of the crimping terminal 110 to the electric wire 101 when the lower mold 14 and the upper mold 16 are close to each other in the vertical direction. The lower mold 14 and the upper mold 16 each have a rectangular parallelepiped shape whose cross section in a horizontal plane is defined in a longitudinal direction coinciding with the axial direction of the crimping forming portion 112 and in a width direction perpendicular to the longitudinal direction.

[0087] The lower mold 14 includes a lower mold setback 22 disposed within the lower mold recess 21 and having a lower mold central protrusion 22a protruding in the crimping direction. The lower mold recess 21 is formed on the lower mold surface 20a facing the crimping direction and contacts the crimping forming portion 112 along its length. The lower mold 14 includes a lower mold recess 23 adjacent to one end of the lower mold setback 22 in the width direction and extending from the lower mold surface 20a in the direction opposite to the crimping direction. Furthermore, the lower mold 14 includes a lower mold protrusion 24 adjacent to the other end of the lower mold setback 22 in the width direction and protruding from the lower mold surface 20a in the crimping direction.

[0088] The upper mold 16 includes an upper mold setback 32 disposed within the upper mold recess 31 and having an upper mold central protrusion 32a protruding in the crimping direction. The upper mold recess 31 is formed on the upper mold surface 30a facing the crimping direction and contacts the crimping forming portion 112 in the longitudinal direction. The upper mold 16 has an upper mold recess 33 adjacent to one end of the upper mold setback 32 in the width direction and extending from the upper mold surface 30a in the direction opposite to the crimping direction. Furthermore, the upper mold 16 has an upper mold protrusion 34 adjacent to the other end of the upper mold setback 32 in the width direction and protruding from the upper mold surface 30a in the crimping direction.

[0089] In the lower mold 14, the lower mold central protrusion 22a of the lower mold setback 22 has a terminal surface 22c, and a front wall surface 22d and a rear wall surface 22e positioned opposite each other in the longitudinal direction. Here, the edge where the front wall surface 22d meets the terminal surface 22c is defined as a first edge 22f, and the edge where the rear wall surface 22e meets the terminal surface 22c is defined as a second edge 22g. The inclination angle of the front wall surface 22d relative to the vertical axis AX originating from the first edge 22f and the inclination angle of the rear wall surface 22e relative to the vertical axis AX originating from the second edge 22g are each defined as a setback angle θ1. The setback angle θ1 is within a range of 20° to 30°. The setback angle θ1 in the upper mold 16 is similarly defined.

[0090] Here, as described above, the vertical direction corresponds to the Z direction, the length direction corresponds to the X direction, and the width direction corresponds to the Y direction. In addition, the crimping direction of the lower mold 14 corresponds to the Z direction, and the crimping direction of the upper mold 16 corresponds to the direction opposite to the Z direction.

[0091] First, according to the pressing die 10, when the lower die 14 and the upper die 16 are closest to each other, the lower die setback 22 and the upper die setback 32 press the crimping forming portion 112 in the Y direction while being held between the lower die convex portion 24 and the upper die convex portion 34 to form the crimping portion 114. At this time, the lower die convex portion 24 and the upper die convex portion 34 restrict the plastic deformation of the crimping forming portion 112 due to expansion of its outer surface in the Y direction, thereby preventing the occurrence of burrs in the crimping portion 114.

[0092] Furthermore, the retraction angle θ1 of the lower die 14 and the retraction angle θ1 of the upper die 16 in the embossing die 10 are within a range of 20° to 30°. Figures 11 to 13 As shown in the graph in , the terminal-attached electric wire 100 manufactured using the swaging die 10 can reduce the voltage drop at the crimping portion 114 when actually used as a product.

[0093] As described above, according to the present embodiment, it is possible to provide a swaging die 10 that improves the electrical performance of the terminal-attached electric wire 100 .

[0094] The method for manufacturing a terminal-attached electric wire 100 according to this embodiment is a method for manufacturing the terminal-attached electric wire 100 by crimping the crimping forming portion 112 of a crimping terminal 110 to an electric wire 101. The method includes the steps of inserting a portion of the electric wire 101 into the crimping forming portion 112 and retaining the crimping forming portion 112, into which the portion of the electric wire 101 is inserted, by a press mold including a lower mold and an upper mold. The press mold is the press mold 10 according to the above-described embodiment.

[0095] According to the manufacturing method, the terminal-fitted electric wire 100 is manufactured using the swaging die 10 , so that the terminal-fitted electric wire 100 having improved electrical performance can be provided.

[0096] Furthermore, the terminal-attached electric wire 100 according to the present embodiment includes a crimping portion 114 formed by clamping the crimping forming portion 112 of the crimping terminal 110, into which a portion of the electric wire 101 is inserted, with a press die 10 including a lower die 14 and an upper die 16. Crimping portion 114 includes a lower crimping recess 114c to which a portion of the convex shape of the lower die 14 is transferred, and an upper crimping recess 114d to which a portion of the convex shape of the upper die 16 is transferred. Lower crimping recess 114c and upper crimping recess 114d each have a bottom surface 114e, and a front inner wall surface 114f and a rear inner wall surface 114g positioned opposite each other in a longitudinal direction aligned with the axial direction of crimping forming portion 112. The corner where the front inner wall surface 114f meets the bottom surface 114e is referred to as a first corner 114h, and the corner where the rear inner wall surface 114g meets the bottom surface 114e is referred to as a second corner 114i. The inclination angle of the front inner wall surface 114f relative to the vertical axis AX originating from the first corner 114h and the inclination angle of the rear inner wall surface 114g relative to the vertical axis AX originating from the second corner 114i are each defined as a recess angle θ2. Therefore, the recess angle θ2 is within a range of 20° to 30°.

[0097] According to the terminal-attached electric wire 100, for example, when the swaging die 10 is used, the concave angle θ2 of the crimping portion 114 is within a range of 20° or more and 30° or less. Figures 11 to 13 As described in the graph in , since the voltage drop at the crimping portion 114 can be reduced when used as a product, the electrical performance of the terminal-attached electric wire 100 can be improved.

[0098] In the above description, the swaging die 10 used for the terminal crimping device 1 is exemplified, but the structure or shape of the swaging die 10 can also be used for a crimping tool.

[0099] Although the present invention has been described above with reference to the embodiment, the present invention is not limited thereto, and the configuration of components can be replaced with any configuration having the same function within the scope of the claims.

Claims

1. A press die comprising a lower die and an upper die for crimping a crimping forming portion of a crimping terminal to an electric wire when the lower die and the upper die are brought close to each other in a vertical direction, wherein: The lower die and the upper die each have a rectangular parallelepiped shape, and a cross section of the rectangular parallelepiped on a horizontal plane is defined in a length direction consistent with the axial direction of the crimping forming portion and in a width direction perpendicular to the length direction. The lower mold and the upper mold each include: a retracted portion provided in the concave portion and having a central convex portion protruding in the crimping direction, the concave portion being formed on a die surface facing the crimping direction and in contact with the crimping forming portion along the longitudinal direction; a recessed portion adjacent to one end of the indented portion in the width direction and extending from the mold surface in a direction opposite to the crimping direction; and a convex portion adjacent to the other end of the indented portion in the width direction and protruding from the mold surface in the crimping direction, The central protrusion of the setback includes a terminal surface and a front wall surface and a rear wall surface positioned opposite to each other in the length direction, and When the end edge where the front wall surface meets the end surface is defined as a first end edge, and the end edge where the rear wall surface meets the end surface is defined as a second end edge; and when the inclination angle of the front wall surface relative to the vertical axis originating from the first end edge and the inclination angle of the rear wall surface relative to the vertical axis originating from the second end edge are each defined as a retraction angle, the retraction angle is within the range of greater than 20° and less than 30°.

2. A method for manufacturing a terminal-attached electric wire in which a crimping forming portion of a crimping terminal is crimped to the electric wire, the method comprising: inserting a portion of the electric wire into the crimp forming portion; as well as The step of clamping the crimping forming portion into which a portion of the electric wire is inserted by a swaging die including a lower die and an upper die, wherein The pressing die is the pressing die according to claim 1.

3. An electric wire equipped with a terminal, comprising: The crimping portion is formed by clamping a crimping forming portion into which a portion of the electric wire is inserted by a pressing die including a lower die and an upper die, The crimping portion includes a lower crimping recess and an upper crimping recess, a convex shape of a portion of the lower die is transferred to the lower crimping recess, and a convex shape of a portion of the upper die is transferred to the upper crimping recess. The lower crimping recess and the upper crimping recess each have a bottom surface, and a front inner wall surface and a rear inner wall surface positioned opposite to each other in a length direction coinciding with an axial direction of the crimping forming portion, and When the corner where the front inner wall surface meets the bottom surface is defined as a first corner, and the corner where the rear inner wall surface meets the bottom surface is defined as a second corner; and when the inclination angle of the front inner wall surface relative to the vertical axis originating from the first corner and the inclination angle of the rear inner wall surface relative to the vertical axis originating from the second corner are defined as recess angles, the recess angles are within a range of greater than 20° and less than 30°.

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