Crimping type, manufacturing method of electric wire with terminal, and electric wire with terminal

Abstract

To provide a crimping type that improves the electrical performance of an electric wire with a terminal.SOLUTION: In a crimping die 10 consisting of a lower die 14 and an upper die 16 that crimps the crimp forming portion 112 of the crimp terminal 110 onto the electric wire 101, when the conductor size of the core wire 102 of the electric wire 101 to which the crimp forming portion 112 is crimped is within the range of 40 sq or more and 95 sq or less, and the wire diameter of the multiple wires that make up the core wire 102 is 0.20 mm or more and 0.80 mm or less, for example, the indent length L1, which is defined as the length in the front-to-rear direction of the tip surface 22c of the lower die central convex portion 22a of the lower die indent portion 22, is 6.5 mm or more.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a crimping die, a method for manufacturing an electric wire with a terminal, and an electric wire with a terminal. [Background technology]

[0002] A terminal crimping device has been known that manufactures a terminal-attached electric wire by crimping the crimp forming portion of a crimp terminal onto the end of an electric wire. Generally, the terminal crimping device uses a crimping die that includes a lower die and an upper die that are held so as to be able to approach or move away from each other in the vertical direction and that, when brought close to each other, plastically deforms the crimp forming portion to form the crimp portion.

[0003] Patent Document 1 discloses a technology relating to a crimping die comprising a lower die and an upper die, each of which has a protruding indentation that contacts the crimping portion, a recess near one widthwise side of the indentation, and a protrusion near the other widthwise side of the indentation. Here, the widthwise direction is perpendicular to the front-to-rear direction, which is aligned with the axial direction of the crimping portion. In this crimping die, when the lower die and the upper die approach each other with the crimping portion placed on the indentation of the lower die, the protrusion of the lower die engages with the recess of the upper die, and the protrusion of the upper die engages with the recess of the lower die. The indentation of the lower die and the indentation of the upper die then press the crimping portion while sandwiching it between the protrusions at both widthwise ends, thereby forming the crimping portion. At this time, each protrusion restricts plastic deformation of the crimping portion so that it extends in the widthwise direction, thereby preventing burrs from forming on the crimping portion and preventing the crimp terminal from fitting into the crimping die. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-42683 Summary of the Invention [Problem to be solved by the invention]

[0005] With the crimping die disclosed in Patent Document 1, the conditions for the shape of the crimping die to improve the electrical performance of the terminal-attached electric wire manufactured using the crimping die are not actually clear, so specific proposals are desired.

[0006] The present invention has been made in view of the problems inherent in the prior art, and an object of the present invention is to provide a crimping type that improves the electrical performance of an electric wire with a terminal, or a method for manufacturing an electric wire with a terminal or an electric wire with a terminal that has improved electrical performance. [Means for solving the problem]

[0007] One aspect of the present invention is a crimping die comprising a lower die and an upper die that, when approaching each other in the vertical direction, crimp the crimp forming portion of a crimp terminal onto an electric wire, wherein the lower die and the upper die are each a rectangular parallelepiped whose cross section on a horizontal plane is defined by a front-to-rear direction aligned with the axial direction of the crimp forming portion and a width direction perpendicular to the front-to-rear direction, and the lower die and the upper die each have an indent portion formed on the side of the die surface facing the crimping direction, which is provided in a concave portion that brings the crimp forming portion into contact along the front-to-rear direction, and has a central convex portion that protrudes in the crimping direction, and a width direction of the indent portion. and a convex portion adjacent to the other end in the width direction of the indent portion and protruding from the die surface in the crimping direction, and the conductor size of the core wire of the electric wire to which the crimped forming portion is crimped is within the range of 40 sq or more and 95 sq or less, and the wire diameters of the multiple wires constituting the core wire are 0.20 mm or more and 0.80 mm or less, the indent length, which is defined as the length in the front-to-rear direction of the tip surface of the central convex portion of the indent portion, is 6.5 mm or more.

[0008] Another aspect of the present invention is a method for manufacturing a terminal-attached electric wire in which a crimp forming portion of a crimp terminal is crimped to an electric wire, the method including the steps of inserting a portion of the electric wire into the crimp forming portion and crimping the electric wire to the crimp forming portion by clamping the crimp forming portion through which the portion of the electric wire has been inserted between a crimping mold consisting of a lower mold and an upper mold, wherein the crimping mold is the crimping mold according to the aspect described above.

[0009] Furthermore, an electric wire with terminal according to one embodiment of the present invention has a crimping portion formed by clamping the crimping portion of a crimp terminal through which a portion of the electric wire is inserted, using a clamping mold consisting of a lower mold and an upper mold, and the crimping portion has a lower crimping recess to which the convex shape of a portion of the lower mold is transferred, and an upper crimping recess to which the convex shape of a portion of the upper mold is transferred, and when the conductor size of the core wire of the electric wire to which the crimping portion is crimped is in the range of 40 sq or more and 95 sq or less, and the wire diameters of the multiple strands constituting the core wire are 0.20 mm or more and 0.80 mm or less, the recess length, defined as the length in the front-to-rear direction aligned with the axial direction of the crimping portion at the bottom surface of each of the lower crimping recess and the upper crimping recess, is 6.5 mm or more. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a crimping type that improves the electrical performance of an electric wire with terminal, or a method for manufacturing an electric wire with terminal or an electric wire with terminal that has improved electrical performance. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view of a terminal crimping device that can employ a crimping die according to one embodiment. [Figure 2] FIG. 1 is a perspective view of an electric wire with a terminal manufactured using a crimping die according to one embodiment. [Figure 3] FIG. 2 is a perspective view showing an electric wire and a crimp terminal before being mounted on a terminal crimping device. [Figure 4] FIG. 2 is a side view of a crimping mold according to one embodiment. [Figure 5] FIG. 2 is a perspective view of a lower mold that constitutes a crimping mold according to one embodiment. [Figure 6] FIG. 10 is a partial cross-sectional view showing the state of the lower mold and the upper mold before they are brought close to each other. [Figure 7] FIG. 4 is a partial cross-sectional view showing the state of the lower mold and the upper mold during crimping. [Figure 8] FIG. 10 is a partial cross-sectional view showing the state of the lower mold and the upper mold after separation. [Figure 9] 6 is a partial cross-sectional view of a lower mold corresponding to the IX-IX portion in FIG. 5. [Figure 10] 3 is a partial cross-sectional view of the electric wire with terminal corresponding to the portion XX in FIG. 2. [Figure 11] 11 is a cross-sectional view of the crimped portion at a position corresponding to the measurement cross section C in FIG. 10. [Figure 12] 4 is a graph showing electrical performance of a first example of an electric wire with a terminal. [Figure 13] 10 is a graph showing electrical performance of a second example of an electric wire with a terminal. [Figure 14] 10 is a graph showing electrical performance of a third example of an electric wire with a terminal. [Figure 15] 4 is a graph showing electrical performance of a first example of an electric wire with a terminal. [Figure 16] 10 is a graph showing electrical performance of a second example of an electric wire with a terminal. [Figure 17] 10 is a graph showing electrical performance of a third example of an electric wire with a terminal. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, a crimping type, a method for manufacturing an electric wire with a terminal, and an electric wire with a terminal according to an embodiment will be described in detail with reference to the drawings. Note that the dimensional proportions in the drawings are exaggerated for the convenience of explanation and may differ from the actual proportions.

[0013] FIG. 1 is a perspective view of a terminal crimping device 1 that can employ a crimping die 10 according to one embodiment. Hereinafter, the directions in the terminal crimping device 1 and the crimping die 10 will be defined as follows, by way of example. The X direction indicates the front-to-rear direction along the axial direction of the crimp terminal 110 attached to the crimping die 10, extending from the rear to the front. The Y direction indicates the width direction perpendicular to the X direction on a horizontal plane. The Z direction indicates the up-down direction extending from the bottom to the top. The X direction may also be referred to as "front" or "rear." The Z direction may also be referred to as "top" or "bottom."

[0014] Fig. 2 is a perspective view of an electric wire with terminal 100 according to one embodiment manufactured using the crimping die 10. Fig. 3 is a perspective view showing an electric wire 101 and a crimp terminal 110 before being mounted on the terminal crimping device 1.

[0015] The terminal crimping device 1 manufactures the electric wire with terminal 100 by crimping the crimp forming portion 112 of the crimp terminal 110 onto the end of the electric wire 101 to form the crimp portion 114 .

[0016] The electric wire 101 may be a so-called high-voltage electric wire that can be used in high-voltage circuits such as electric vehicles. The electric wire 101 has a core 102 and a sheath 103 that covers the core 102. The core 102 is, for example, a stranded wire made of multiple strands of annealed copper. For convenience, in the corresponding drawings below, the core 102 is depicted as a cross section of a single conductor. The sheath 103 is an insulating member made of synthetic resin such as polyethylene. Before being loaded into the terminal crimping device 1, the end of the electric wire 101 has the sheath 103 stripped off, exposing a portion of the core 102 to the outside, as shown in FIG. 3.

[0017] As described above, the crimp terminal 110 is a terminal fitting that is crimped to the end of the electric wire 101, specifically, to the core wire 102 that has been stripped of the coating 103 and is exposed to the outside. The crimp terminal 110 is made of, for example, so-called pure copper, which has a copper content of 99.90% or more, and may be further plated with silver or the like. Here, the pure copper may be oxygen-free copper, tough pitch copper, phosphorus-deoxidized copper, or the like. The crimp terminal 110 is rod-shaped overall and has a connection portion 111, a crimp forming portion 112, and a flange portion 113.

[0018] As an example, the connection portion 111 is a cylindrical portion located on the front side in the X direction along the axial direction of the crimp terminal 110. The connection portion 111 is connected to a counterpart connection portion of a counterpart terminal, thereby electrically connecting the crimp terminal 110 and the counterpart terminal.

[0019] The crimp forming portion 112 is a cylindrical portion located on the rear side of the crimp terminal 110 in the X direction via the flange portion 113. The crimp forming portion 112 extends along the axial direction of the crimp forming portion 112 and has an insertion hole 112a through which the tip end of the core wire 102 is inserted. In other words, the crimp terminal 110 employed in this embodiment is a so-called closed barrel type.

[0020] The flange portion 113 is a cylindrical portion located between the connection portion 111 and the crimping portion 112, and protruding radially outward from the outer circumferential surface of the crimping portion 112. An annular groove 113a may be formed on the outer periphery of the flange portion 113, to which a sealing part can be attached.

[0021] The terminal crimping device 1 includes a base 11, a wire holding section 12, a frame 13, a lower die 14, a movement restricting section 15, an upper die 16, and a driving means (not shown). Here, the lower die 14 and the upper die 16 constitute a crimping die 10 according to this embodiment.

[0022] The base 11 is, for example, a block-shaped structure such as a rectangular parallelepiped that is fixed onto a work table on which the terminal crimping device 1 is placed.

[0023] The electric wire holding portion 12 is fixed to the base 11 and has a first holding portion 12a on which the electric wire 101 is placed, and a second holding portion 12b configured to be movable toward and away from the first holding portion 12a in the Z direction and capable of holding the electric wire 101 placed on the first holding portion 12a. The first holding portion 12a is located in the center in the Y direction and has a groove 12c extending in the X direction, and by placing the electric wire 101 in the groove 12c, movement of the electric wire 101 along the Y direction is restricted. First, the electric wire 101 is placed on the first holding portion 12a in a state in which the second holding portion 12b is spaced apart from the first holding portion 12a in the Z direction. Thereafter, the electric wire holding portion 12 brings the second holding portion 12b closer to the first holding portion 12a along the Z direction, and finally, the electric wire 101 is sandwiched between the first holding portion 12a and the second holding portion 12b. In a state in which the electric wire 101 is sandwiched between the first holding portion 12a and the second holding portion 12b, movement of the electric wire 101 along each of the X direction, Y direction, and Z direction is restricted.

[0024] The frame 13 is fixed to the base 11 and has a frame main body 13a and a frame support portion 13b that supports the upper mold 16 movably along the Z direction relative to the frame main body 13a.

[0025] Fig. 4 is a perspective view of the crimping die 10 at a drawing angle that allows the front side in the X direction to be seen. Fig. 4 shows the crimping die 10 in a state in which the crimping forming portion 112 of the crimp terminal 110 is placed on the lower die 14 and the crimping forming portion 112 has not yet been sandwiched between the lower die 14 and the upper die 16. Fig. 5 is a perspective view of the lower die 14 at a drawing angle that allows the front side in the X direction to be seen.

[0026] The lower die 14 is one of the pair of dies that form the crimping die 10 and the upper die 16, sandwiching and pressing the crimping forming portion 112. The lower die 14 is sometimes called an "anvil." The lower die 14 has a lower die main body portion 20 and a lower die recessed portion 21.

[0027] The lower mold body 20 is a rectangular parallelepiped block whose cross section on a horizontal plane is defined by the X and Y directions. The lower mold body 20 has a lower mold surface 20a. The lower mold surface 20a faces the upper mold 16 and is the mold surface on the lower mold 14 side that is adjacent to the upper mold surface 30a (see FIG. 6) when the lower mold 14 and the upper mold 16 are assembled.

[0028] The lower mold recess 21 is located at the center of the lower mold surface 20a in the Y direction in the lower mold main body 20, and is formed as if it were grooved along the X direction. The lower mold recess 21 has a lower mold bottom surface 21a whose width in the Y direction is narrower than the width of the opening in the Y direction at the opening surface that opens on the lower mold surface 20a. The lower mold recess 21 also has a first inclined side surface 21b and a second inclined side surface 21c that are symmetrical with each other in the Y direction with respect to the lower mold bottom surface 21a. One end of the first inclined side surface 21b is continuous with one end edge of the lower mold bottom surface 21a along 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 edge of the lower mold bottom surface 21a along the X direction, and the other end of the second inclined side surface 21c is continuous with the lower mold surface 20a. The first inclined side surface 21b and the second inclined side surface 21c are each inclined in the Y direction from the lower mold bottom surface 21a toward the lower mold surface 20a so as to move away from the lower mold bottom surface 21a. The lower mold concave portion 21 also has a lower mold indent portion 22 as an indent portion provided in the lower mold 14.

[0029] The lower die indent portion 22 is located on the lower die bottom surface 21a, and the crimp forming portion 112 is placed thereon. When the lower die indent portion 22 is crimped onto the tip of the electric wire 101, the shape of the lower die indent portion 22 is transferred to the crimping portion 114, and a lower crimping portion 114a of the crimping portion 114 is formed (see FIGS. 7 and 8). The lower die indent portion 22 includes a lower die central convex portion 22a and a pair of lower die indent bottom surfaces 22b. The lower die central convex portion 22a is lower than the lower die surface 20a in the Z direction, is located at the center of the lower die main body portion 20 in the Y direction, and protrudes in the crimping direction. Here, the crimping direction for the lower die 14 is from bottom to top along the Z direction. The pair of lower die indent bottom surfaces 22b are located on either side of the lower die central protrusion 22a in the Y direction, and are formed lower in the Z direction than the lower die central protrusion 22a. One of the lower die indent bottom surfaces 22b is continuous with the first inclined side surface 21b. The other lower die indent bottom surface 22b is continuous with the second inclined side surface 21c.

[0030] Hereinafter, the width of the lower die central convex portion 22a in the Y direction is defined as the indent width W. Also, the height in the Z direction from the bottom surface 22b of the lower die indent to the tip surface 22c of the lower die central convex portion 22a is defined as the indent height H.

[0031] The lower mold 14 also has a lower mold recess 23 and a lower mold protrusion 24. The lower mold recess 23 and the lower mold protrusion 24 are adjacent to each other in the Y direction, with the lower mold recess 21 including the lower mold indent 22 sandwiched therebetween.

[0032] Lower mold recess 23 is adjacent to one end of lower mold indent portion 22 in the Y direction via first inclined side surface 21b, and is formed downward in the Z direction from lower mold surface 20a. Lower mold recess 23 has a bottom surface 23a (see FIG. 6), a first inner surface 23b and a second inner surface 23c (see FIG. 6) that face each other in the Y direction, and a third inner surface 23d (see FIG. 6) and a fourth inner surface 23e that face each other in the X direction. Here, of the multiple inner surfaces that form lower mold recess 23, first inner surface 23b is closest to lower mold indent portion 22.

[0033] The lower mold protrusion 24 is adjacent to the other end of the lower mold indentation 22 in the Y direction via the second inclined side surface 21c, and protrudes upward in the Z direction from the lower mold surface 20a. Note that the lower mold protrusion 24 can be regarded as an upright wall directly to the side of the lower mold indentation 22, and is therefore sometimes referred to as a "side wall" or "support." The lower mold protrusion 24 has an end surface 24a, a first outer surface 24b and a second outer surface 24c (see FIG. 6) that face each other in the Y direction, and a third outer surface 24d and a fourth outer surface 24e that face each other in the X direction. Here, of the multiple outer surfaces that form the lower mold protrusion 24, the first outer surface 24b is closest to the lower mold indentation 22.

[0034] 1, the movement restricting portion 15 is located on the front side in the X direction with respect to the lower mold 14. The movement restricting portion 15 has a restricting portion main body 15a and a pair of flange receiving portions 15b.

[0035] The restricting portion main body 15a is, for example, a rectangular parallelepiped block. The pair of flange receiving portions 15b protrude upward from the upper surface of the restricting portion main body 15a while being spaced apart in the Y direction. The connecting portion 111 of the crimp terminal 110 is inserted between one flange receiving portion 15b and the other flange receiving portion 15b, thereby restricting movement of the crimp terminal 110 along the Y direction. Furthermore, when the crimp forming portion 112 is placed on the lower die indent portion 22, the pair of flange receiving portions 15b come into contact with the flange portion 113 of the crimp forming portion 112 in the X direction, thereby restricting forward movement of the crimp terminal 110 in the X direction.

[0036] The upper die 16 is the part of the crimping die 10 that is supported by the frame 13. The upper die 16 is sometimes referred to as a "crimper." The upper die 16 is supported by the frame support portion 13b and faces the lower die 14 in the Z direction. The upper die 16 moves toward and away from the lower die 14 as the frame support portion 13b moves along the Z direction relative to the frame main body 13a. Here, the crimping direction for the upper die 16 is from top to bottom along the Z direction. The shape of the upper die 16 is such that the lower die 14 is rotated 180° while maintaining parallelism with the YZ plane. In other words, the main shape of the upper die 16 is the same as the shape of the lower die 14. However, there may be differences between the lower die 14 and the upper die 16, such as their lengths in the Z direction.

[0037] The upper mold 16 also has an upper mold main body 30 and an upper mold recess 31. The tip of the upper mold main body 30 has the same shape as the lower mold main body 20, and its length in the Z direction is longer than that of the lower mold main body 20. The mold surface on the upper mold main body 30 is the upper mold surface 30a. The upper mold recess 31 has the same shape as the lower mold recess 21, has an upper mold bottom surface 31a (see Figure 6), and faces the lower mold recess 21 in the Z direction. The upper mold indent 32 (see Figure 6) has the same shape as the lower mold indent 22, and faces the lower mold indent 22 in the Z direction. By crimping the crimp forming portion 112 onto the tip of the electric wire 101, the shape of the upper die indent portion 32 is transferred to the crimping portion 114, forming an upper crimping portion 114b of the crimping portion 114 (see FIGS. 7 and 8). The upper die indent portion 32 also includes an upper die central convex portion 32a and a pair of upper die indent bottom surfaces 32b. One of the upper die indent bottom surfaces 32b is continuous with the first inclined side surface 31b. The other upper die indent bottom surface 32b is continuous with the second inclined side surface 31c.

[0038] Furthermore, the upper mold 16 has an upper mold recess 33 (see FIG. 6) and an upper mold protrusion 34. The upper mold recess 33 has the same shape as the lower mold recess 23, and engages with the lower mold protrusion 24 when approaching the lower mold 14. The upper mold protrusion 34 has the same shape as the lower mold protrusion 24, and engages with the lower mold recess 23 when approaching the lower mold 14. Note that, like the lower mold protrusion 24, the upper mold protrusion 34 is considered to be an upright wall directly to the side of the upper mold indent 32, and is therefore sometimes referred to as a "side wall" or "support."

[0039] Furthermore, the driving means moves the frame support portion 13b along the Z direction relative to the frame main body 13a, thereby moving the upper mold 16 toward and away from the lower mold 14 along the Z direction.

[0040] Next, a manufacturing process of the electric wire with terminal 100 using the terminal crimping device 1 equipped with the crimping die 10 will be described.

[0041] Fig. 6 is a cross-sectional view of the crimping die 10 corresponding to the portion VI-VI in Fig. 1. Specifically, Fig. 6 is a partial cross-sectional view showing the state of the lower die 14 and the upper die 16 before the crimp forming portion 112 of the crimp terminal 110 is placed on the lower die indent portion 22 of the lower die 14 and before the crimp forming portion 112 is crimped to the electric wire 101, i.e., before they approach each other.

[0042] Figure 7 is a partial cross-sectional view showing the state of the lower mold 14 and upper mold 16 in which the upper mold 16 has been moved closer to the lower mold 14 from the state shown in Figure 6, and the compression forming portion 112 is pressed to form the compression forming portion 114.

[0043] Figure 8 is a partial cross-sectional view showing the state in which the finally formed crimped portion 114 exists on the lower mold indent portion 22 of the lower mold 14 after the upper mold 16 has been separated from the lower mold 14 from the state shown in Figure 7.

[0044] First, the terminal crimping apparatus 1 performs a step of inserting a portion of the electric wire 101 into the crimp forming portion 112. Specifically, the crimp terminal 110 is attached to a predetermined position of the terminal crimping apparatus 1 so that the crimp forming portion 112 is placed on the lower die indent portion 22. Next, the electric wire 101 is placed on the first holding portion 12a of the electric wire holding portion 12, and then the core wire 102 of the electric wire 101 is inserted into the insertion hole 112a of the crimp forming portion 112. Next, the second holding portion 12b is brought close to the first holding portion 12a, so that the electric wire 101 is clamped between the first holding portion 12a and the second holding portion 12b. The state of the crimp forming portion 112 at this stage is as shown in FIG. 6.

[0045] Next, the terminal crimping apparatus 1 performs a step of actually crimping the electric wire 101 onto the crimp forming portion 112. Specifically, the terminal crimping apparatus 1 drives the driving means to move the upper die 16 toward the lower die 14. By this operation, as shown in FIG. 7 , the upper die 16 approaches the lower die 14, and the crimp forming portion 112 is sandwiched and pressed (compressed) between the lower die indent portion 22 and the upper die indent portion 32. At this time, the crimp forming portion 112 extends in the Y direction while being compressed in the Z direction, and finally, the shapes of the lower die indent portion 22 and the upper die indent portion 32 are transferred to the crimp terminal 110, forming the crimp portion 114. In this way, the terminal crimping device 1 crimps the core wire 102 inserted into the insertion hole 112a of the crimp terminal 110 to the crimp forming portion 112, thereby producing a terminal-attached electric wire 100 in which the crimp terminal 110 and the electric wire 101 are integrated as shown in Figure 2.

[0046] Thereafter, the terminal crimping device 1 drives the driving means again to move the upper die 16 in a direction away from the lower die 14. By this operation, the upper die 16 and the lower die 14 are separated from each other, as shown in Fig. 8, and the electric wire with terminal 100 is ready to be taken out from above the lower die 14.

[0047] Next, we will explain how to set the indent length L1 and the compression ratio in the crimping portion 114, which are factors that determine the shapes of the lower mold indent portion 22 and the upper mold indent portion 32. Here, since the shape of the lower mold indent portion 22 and the shape of the upper mold indent portion 32 are the same, we will focus on the lower mold indent portion 22 and explain how to set them.

[0048] Fig. 9 is a partial cross-sectional view of the lower mold 14 corresponding to the IX-IX portion in Fig. 5. The cross section in Fig. 9 is a virtual XZ plane that passes through the middle position of the lower mold indent portion 22 in the width direction corresponding to the Y direction of the lower mold 14.

[0049] First, in the front-rear direction corresponding to the X direction of the lower mold 14, the width of the lower mold main body portion 20 is defined as a first width W1, and the width of the lower mold convex portion 24 is defined as a second width W2. The second width W2 is shorter than the first width W1. Similarly, in the front-rear direction, the length of the tip surface 22c of the lower mold central convex portion 22a in the lower mold indent portion 22 is defined as an indent length L1. The lower mold indent portion 22 is positioned within the range defined by the second width W2 in the front-rear direction. In other words, the indent length L1 is shorter than the second width W2.

[0050] The lower mold indent portion 22 has a front wall surface 22d and a rear wall surface 22e, which are wall portions positioned opposite each other in the front-to-rear direction. The front wall surface 22d and the rear wall surface 22e are inclined so that the distance between them in the front-to-rear direction gradually increases from the tip 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 intersects with the tip surface 22c is defined as a first edge 22f, and the edge where the rear wall surface 22e intersects with the tip surface 22c is defined as a second edge 22g. The inclination angle of the front wall surface 22d from the first edge 22f to the vertical axis AX and the inclination angle of the rear wall surface 22e from the second edge 22g to the vertical axis AX are defined as indent angles θ1, respectively. In this case, the indent angle θ1 is set within a range of 20° to 30°.

[0051] Fig. 10 is a partial cross-sectional view of the electric wire with terminal 100 corresponding to the portion XX in Fig. 2. Specifically, Fig. 10 is a cross-sectional view of the crimping portion 114 and its surroundings of the electric wire with terminal 100. The cross section in Fig. 10 is a virtual XZ plane passing through the central axis of the crimp terminal 110.

[0052] In the crimping portion 114, the shape of the lower die indent portion 22 is transferred to form the lower crimping portion 114a, and the shape of the upper die indent portion 32 is transferred to form the upper crimping portion 114b. In the lower crimping portion 114a, the portion where the lower die central convex portion 22a abuts is deeply recessed to form the lower crimping recess 114c. Similarly, in the upper crimping portion 114b, the portion where the upper die central convex portion 32a abuts is deeply recessed to form the upper crimping recess 114d.

[0053] Each of the lower crimping recess 114c and the upper crimping recess 114d has a bottom surface 114e and a front inner wall surface 114f and a rear inner wall surface 114g located opposite each other in the front-to-rear direction. The front inner wall surface 114f and the rear inner wall surface 114g are inclined so that the distance between them in the front-to-rear direction gradually narrows from the main surface of the lower crimping portion 114a or the upper crimping portion 114b toward the bottom surface 114e. Here, the length of the bottom surface 114e in the front-to-rear direction is defined as the recess length L2.

[0054] Furthermore, in crimping portion 114, the portion that is located at the rear end closest to sheath portion 103 of wire 101 in the front-to-rear direction corresponding to the X direction and that does not directly form lower crimping recess 114c and upper crimping recess 114d will hereinafter be referred to as the "rear bell-mouth portion." In Figure 10, the portion corresponding to rear bell-mouth portion 114j is shown enclosed in a dash-dotted line frame.

[0055] 11 is a cross-sectional view of the crimped portion 114 at a position corresponding to the measurement cross-section C in FIG. 10. Specifically, the measurement cross-section C is a YZ plane that passes through the middle position of the crimped portion 114 in the front-rear direction corresponding to the X direction. Hereinafter, with respect to the conductor corresponding to the core wire 102 of the electric wire 101, the compression ratio (%) at the measurement cross-section C is expressed as [the cross-sectional area of ​​the conductor after crimping (mm 2 It is expressed as the value obtained by multiplying [(cross-sectional area of ​​the conductor before crimping (mm2)] by 100.

[0056] In the crimping portion 114, the core wire 102, which is a bundle of multiple wires, is crushed within the insertion hole 112a by being sandwiched between the lower crimping portion 114a and the upper crimping portion 114b, so that the core wire 102 is in close contact with the crimp terminal 110 and an electrical conduction path is ensured.

[0057] Next, with reference to each of Figs. 12 to 14, the measurement results of the voltage drop at the crimping portion 114 relative to the indent length L1 will be described as the electrical performance of the electric wire with terminal 100.

[0058] Fig. 12 is a graph showing the ratio of the voltage drop at the crimped portion 114 to the indent length L1 as the electrical performance of the first example of the electric wire with terminal 100. In Fig. 12, the horizontal axis is the indent length L1 (mm) and the vertical axis is the ratio when the voltage drop when the indent length L1 is 8.0 mm is set to 1.0. The voltage drop at the crimped portion 114 was measured by changing the indent length L1 under the following various conditions, and the measurement results shown in Fig. 12 were obtained.

[0059] The electric wire 101 in the first example has a core wire 102 made of multiple strands of annealed copper with a strand diameter of 0.32 mm. The conductor size of the core wire 102 is 40 sq (conductor cross-sectional area: 39.73 mm). 2 )

[0060] The main material of the crimp terminal 110 in the first example is oxygen-free copper. The crimp terminal 110 is plated with copper / silver as a base and is further plated with silver. The thickness of the crimp forming portion 112 is 2.2 mm.

[0061] Furthermore, the conditions for the shapes of the lower die indent portion 22 and the upper die indent portion 32 of the lower die 14 and upper die 16 used in manufacturing the electric wire with terminal 100 of the first example are as follows: The indent width W is 3.0 mm. The indent height H is 1.5 mm.

[0062] First, as a first measurement result in the first example, when the indent length L1 was 8.0 mm, that is, when the recess length L2 at the crimped portion 114 was approximately 8.0 mm, the voltage drop was determined to be within the acceptable range for the electrical performance of the terminal-attached electric wire 100. Here, the lower the voltage drop ratio is below 1.0, the better the electrical performance is determined to be, and the higher the voltage drop ratio is above 1.0, the worse the electrical performance is determined to be.

[0063] As a second measurement result in the first example, when the indent length L1 was 3.0 mm, that is, when the recess length L2 at the crimping portion 114 was approximately 3.0 mm, the voltage drop ratio was 8.2. Since this ratio is significantly higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is inferior.

[0064] As a third measurement result in the first example, when the indent length L1 was 4.0 mm, that is, when the recess length L2 at the crimping portion 114 was approximately 4.0 mm, the voltage drop ratio was 1.7. Since this ratio is higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is inferior.

[0065] As a fourth measurement result in the first example, when the indent length L1 was 5.0 mm, that is, when the recess length L2 at the crimping portion 114 was approximately 5.0 mm, the voltage drop ratio was 1.5. Since this ratio is higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is inferior.

[0066] As a fifth measurement result in the first example, when the indent length L1 was 6.5 mm, that is, when the recess length L2 at the crimping portion 114 was approximately 6.5 mm, the voltage drop ratio was 1.1. Since this ratio is equivalent to 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0067] Furthermore, in the sixth measurement result of the first example, when the indent length L1 was 12.5 mm, that is, when the recess length L2 in the crimping portion 114 was approximately 12.5 mm, the voltage drop ratio was 2.2. Because this ratio is higher than 1.0, it is determined that the electrical performance of the terminal-fitted electric wire 100 is inferior. However, in this case, because the indent length L1 was set relatively long, the lower crimping recess 114c and the upper crimping recess 114d were formed in the crimping portion 114 all the way to the rear end, and therefore the rear bellmouth portion 114j did not exist.

[0068] Therefore, in terms of the electrical performance of the first example of the electric wire with terminal 100, it is considered desirable that the rear bellmouth portion 114j be present and that the indent length L1 be 6.5 mm or more in terms of the voltage drop at the crimping portion 114. Under these conditions, when the indent length L1 is set to 8.0 mm or more, it is considered that the voltage drop at the crimping portion 114 will be stable within a good range. Note that, although the core wire 102 of the electric wire 101 in the first example is made up of multiple annealed copper wires each having a wire diameter of φ0.32 mm, similar results can be obtained when the core wire 102 is made up of multiple annealed copper wires each having a wire diameter of φ0.20 mm.

[0069] Fig. 13 is a graph showing the ratio of the voltage drop at the crimped portion 114 to the indent length L1 as the electrical performance of the second example of the electric wire with terminal 100. In Fig. 13, the horizontal axis is the indent length L1 (mm) and the vertical axis is the ratio when the voltage drop when the indent length L1 is 7.25 mm is set to 1.0. The voltage drop at the crimped portion 114 was measured by changing the indent length L1 under the following various conditions, and the measurement results shown in Fig. 12 were obtained.

[0070] The electric wire 101 in the second example has a core wire 102 made of multiple strands of annealed copper with a strand diameter of 0.32 mm. The conductor size of the core wire 102 is 95 sq (conductor cross-sectional area: 96.27 mm). 2 )

[0071] The main material of the crimp terminal 110 in the second example is tough pitch copper. The crimp terminal 110 is plated with copper / silver as a base and is further plated with silver. The thickness of the crimp forming portion 112 is 2.0 mm.

[0072] In the lower mold 14 and the upper mold 16 used in manufacturing the electric wire with terminal 100 of the second example, the conditions for the shapes of the lower mold indent portion 22 and the upper mold indent portion 32, which are the respective indent portions, are as follows: The indent width W is 3.95 mm. The indent height H is 2.55 mm.

[0073] First, as a first measurement result in the second example, when the indent length L1 was 7.25 mm, that is, when the recess length L2 at the crimped portion 114 was approximately 7.25 mm, the voltage drop was determined to be within the acceptable range for the electrical performance of the terminal-attached electric wire 100. Here, the lower the voltage drop ratio is below 1.0, the better the electrical performance is determined to be, and the higher the voltage drop ratio is above 1.0, the worse the electrical performance is determined to be.

[0074] Furthermore, as a second measurement result of the second example, when the indent length L1 was 11.6 mm, that is, when the recess length L2 at the crimping portion 114 was approximately 11.6 mm, the voltage drop ratio was 0.7. Since this ratio is lower than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0075] Therefore, the electrical performance of the second example of the electric wire with terminal 100, with regard to the voltage drop at the crimping portion 114, satisfies the conditions assumed in the first example. The conditions referred to here are that the rear bell-mouth portion 114j is present and that the indent length L1 is desirably 6.5 mm or more. Note that while the core wire 102 of the electric wire 101 in the second example is composed of multiple annealed copper wires each having a wire diameter of 0.32 mm, similar results can be obtained when the core wire 102 is composed of multiple annealed copper wires each having a wire diameter of 0.20 mm.

[0076] Fig. 14 is a graph showing the ratio of the voltage drop at the crimped portion 114 to the indent length L1 as the electrical performance of the third example of the electric wire with terminal 100. In Fig. 14, the horizontal axis is the indent length L1 (mm), and the vertical axis is the ratio, where the voltage drop when the indent length L1 is 8.0 mm under the wire diameter conditions of the first example is set to 1.0. The voltage drop at the crimped portion 114 was measured under the following various conditions, and the measurement results shown in Fig. 14 were obtained.

[0077] The electric wire 101 in the third example has a core wire 102 made up of a plurality of strands of annealed copper, each strand having a diameter of 0.80 mm. The conductor size of the core wire 102 is 40 sq.

[0078] The crimp terminal 110 in the third example is the same as the crimp terminal 110 in the first example. The lower mold 14 and upper mold 16 used in manufacturing the electric wire with terminal 100 in the third example are the same as those used in manufacturing the electric wire with terminal 100 in the first example.

[0079] As a result of the measurements in Example 3, when the wire diameter was changed to φ0.80 mm from the conditions in Example 1, the voltage drop ratio was 0.12 when the indent length L1 was 8.0 mm, i.e., when the recess length L2 at the crimped portion 114 was approximately 8.0 mm. This ratio is the same as 1.0 in Example 1, so it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0080] Therefore, as for the electrical performance of the third example of the electric wire with terminal 100, the voltage drop at the crimping portion 114 satisfies the conditions assumed in the first example.

[0081] Next, with reference to each of Figs. 15 to 17, the measurement results of the voltage drop versus the compression ratio at the crimping portion 114 will be described as the electrical performance of the electric wire with terminal 100.

[0082] Fig. 15 is a graph showing the ratio of voltage drop to compression ratio at the crimping portion 114 as the electrical performance of the first example of the electric wire with terminal 100. In Fig. 15, the horizontal axis represents the compression ratio (%) at the crimping portion 114, and the vertical axis represents the ratio when the voltage drop at a compression ratio of 58.3% is set to 1.0. For the first example of the electric wire with terminal 100, the compression ratio was changed and the voltage drop at the crimping portion 114 was measured, and the measurement results shown in Fig. 15 were obtained.

[0083] First, as a first measurement result in the first example, the voltage drop when the compression ratio was 58.3% was determined to be within an acceptable range for the electrical performance of the terminal-attached electric wire 100. Here, the lower the voltage drop ratio is below 1.0, the better the electrical performance is determined to be, and the higher the voltage drop ratio is above 1.0, the worse the electrical performance is determined to be.

[0084] As a second measurement result in the first example, the voltage drop ratio when the compression ratio was 40.9% was 0.3. Since this ratio is lower than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0085] As a third measurement result in the first example, the voltage drop ratio when the compression ratio was 72.2% was 2.19. Since this ratio is higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is poor.

[0086] As a fourth measurement result in the first example, the voltage drop ratio when the compression ratio was 79.6% was 6.19. Since this ratio is higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is poor.

[0087] Furthermore, in the fifth measurement result of the first example, the voltage drop ratio when the compression ratio was 103.6% was 8.06. Since this ratio is higher than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is inferior.

[0088] Thus, according to the tendency of the voltage drop in the crimping portion 114 shown in FIG. 15, it can be understood that the higher the compression ratio, the higher the voltage drop, that is, the lower the electrical performance.

[0089] Therefore, as the electrical performance of the first example of the electric wire with terminal 100, it is considered desirable to set the compression ratio to 70% or less with regard to the voltage drop at the crimping portion 114. On the other hand, it is desirable that the lower limit of the compression ratio is a value that satisfies the conditions that the tensile strength is ensured at the crimping portion 114 and that the core wire 102 is not broken.

[0090] Fig. 16 is a graph showing the ratio of voltage drop to compression ratio at the crimping portion 114 as the electrical performance of the second example of the electric wire with terminal 100. In Fig. 16, the horizontal axis represents the compression ratio (%) at the crimping portion 114, and the vertical axis represents the ratio when the voltage drop at a compression ratio of 60.6% is set to 1.0. For the second example of the electric wire with terminal 100, the compression ratio was changed and the voltage drop at the crimping portion 114 was measured, and the measurement results shown in Fig. 16 were obtained.

[0091] First, as a first measurement result in the second example, the voltage drop when the compression ratio was 60.6% was determined to be within the acceptable range for the electrical performance of the terminal-attached electric wire 100. Here, the lower the voltage drop ratio is below 1.0, the better the electrical performance is determined to be, and the higher the voltage drop ratio is above 1.0, the worse the electrical performance is determined to be.

[0092] As a second measurement result of the second example, the voltage drop ratio when the compression ratio was 41.4% was 0.58. Since this ratio is lower than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0093] As a third measurement result of the second example, the voltage drop ratio when the compression ratio was 54.5% was 0.6. Since this ratio is lower than 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0094] As a fourth measurement result of the second example, the voltage drop ratio when the compression ratio was 65.4% was 1.28. Since this ratio is equivalent to 1.0, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0095] Therefore, the electrical performance of the second example of the electric wire with terminal 100 satisfies the conditions assumed in the first example with regard to the voltage drop at the crimping portion 114. The conditions referred to here are that the compression ratio is set to 70% or less, and the lower limit of the compression ratio is a value that satisfies the conditions that the tensile strength is ensured at the crimping portion 114 and that the core wire 102 does not break.

[0096] Fig. 17 is a graph showing the ratio of voltage drop to compression ratio at the crimping portion 114 as the electrical performance of the third example of the electric wire with terminal 100. In Fig. 17, the horizontal axis is the compression ratio (%) at the crimping portion 114, and the vertical axis is the ratio when the voltage drop when the compression ratio is 58.3% under the wire diameter conditions of the first example is set to 1.0. For the third example of the electric wire with terminal 100, the compression ratio was changed and the voltage drop at the crimping portion 114 was measured, and the measurement results shown in Fig. 17 were obtained.

[0097] As a measurement result of Example 3, when the wire diameter was changed to φ0.80 mm from the conditions of Example 1, the voltage drop ratio was 0.14 when the compression rate was 60.3%. Since this ratio is lower than 1.0 in Example 1, it is determined that the electrical performance of the electric wire with terminal 100 is good.

[0098] Therefore, as for the electrical performance of the third example of the electric wire with terminal 100, the voltage drop at the crimping portion 114 satisfies the conditions assumed in the first example.

[0099] Next, the effects of the crimping die 10, the method for manufacturing the electric wire with terminal 100, and the electric wire with terminal 100 will be described.

[0100] The crimping die 10 according to this embodiment comprises a lower die 14 and an upper die 16 that, when they approach each other in the vertical direction, crimp the crimp forming portion 112 of the crimp terminal 110 onto the electric wire 101. The lower die 14 and the upper die 16 each have a rectangular parallelepiped shape whose cross section on the horizontal plane is defined by a front-to-rear direction aligned with the axial direction of the crimp forming portion 112 and a width direction perpendicular to the front-to-rear direction.

[0101] The lower die 14 has a lower die indentation 22 provided in a lower die recess 21 formed on the side of the lower die surface 20a facing the crimping direction and contacting the crimping forming portion 112 along the front-to-rear direction, and having a lower die central protrusion 22a protruding in the crimping direction. The lower die 14 has a lower die recess 23 adjacent to one end in the width direction of the lower die indentation 22 and formed from the lower die surface 20a in the opposite direction to the crimping direction. The lower die 14 also has a lower die protrusion 24 adjacent to the other end in the width direction of the lower die indentation 22 and protruding from the lower die surface 20a in the crimping direction.

[0102] The upper die 16 has an upper die indentation portion 32 provided in an upper die recess 31 formed on the side of the upper die surface 30a facing the crimping direction and contacting the crimping forming portion 112 along the front-to-rear direction, and having an upper die central protrusion 32a protruding in the crimping direction. The upper die 16 has an upper die recess 33 adjacent to one end in the width direction of the upper die indentation portion 32 and formed from the upper die surface 30a in the opposite direction to the crimping direction. The upper die 16 also has an upper die protrusion 34 adjacent to the other end in the width direction of the upper die indentation portion 32 and protruding from the upper die surface 30a in the crimping direction.

[0103] Also, assume that the conductor size of the core wire 102 of the electric wire 101 to be crimped by the crimp forming portion 112 is within a range of 40 sq. to 95 sq., and that the strand diameter of the multiple strands constituting the core wire 102 is 0.20 mm to 0.80 mm. In this case, in the lower die 14, the indent length L1, which is defined as the length in the front-to-rear direction of the tip end surface 22c of the lower die central convex portion 22a of the lower die indent portion 22, is 6.5 mm or more. The indent length L1 in the upper die 16 is defined similarly.

[0104] In the above example, the up-down direction corresponds to the Z direction, the front-rear direction corresponds to the X direction, and the width direction corresponds to the Y direction. 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.

[0105] First, with the crimping die 10, when the lower die 14 and the upper die 16 are closest to each other, the lower die indent portion 22 and the upper die indent portion 32 press the crimp-forming portion 112 while being sandwiched between the lower die convex portion 24 and the upper die convex portion 34 in the Y direction, thereby forming the crimped portion 114. At this time, the lower die convex portion 24 and the upper die convex portion 34 restrict the plastic deformation of the crimp-forming portion 112 on their respective outer surfaces so that the crimped portion 112 extends along the Y direction, thereby preventing burrs from being generated in the crimped portion 114.

[0106] Furthermore, the indent length L1 is set to 6.5 mm or more in each of the lower die 14 and the upper die 16 of the crimping die 10. Therefore, as described with reference to the graphs in Fig. 12 to Fig. 14, the electric wire with terminal 100 manufactured using the crimping die 10 can reduce the voltage drop at the crimping portion 114 when actually used as a product.

[0107] As described above, according to this embodiment, it is possible to provide the crimping die 10 that improves the electrical performance of the electric wire with terminal 100.

[0108] The manufacturing method for the electric wire with terminal 100 according to this embodiment is a manufacturing method for the electric wire with terminal 100 in which the crimp forming portion 112 of the crimp terminal 110 is crimped to the electric wire 101. The manufacturing method includes a step of inserting a portion of the electric wire 101 into the crimp forming portion 112, and a step of clamping the crimp forming portion 112, through which the portion of the electric wire 101 has been inserted, between a crimping die consisting of a lower die and an upper die, thereby crimping the electric wire 101 to the crimp forming portion 112. The crimping die is the crimping die 10 according to the above-described embodiment.

[0109] According to this manufacturing method, the electric wire with terminal 100 is manufactured using the above-mentioned crimping die 10, so that it is possible to provide the electric wire with terminal 100 with improved electrical performance.

[0110] Furthermore, in the manufacturing method of the electric wire with terminal 100, the crimping portion 114 formed by being clamped by the crimping die 10 may have a lower crimping recess 114c to which the shape of the lower die central convex portion 22a of the lower die indent portion 22 is transferred, and similarly an upper crimping recess 114d. In this case, the crimping die 10 may clamp the crimping forming portion 112 so that the rear end portion in the front-to-rear direction of the crimping portion 114 has a rear bell-mouth portion 114j where the lower crimping recess 114c and the upper crimping recess 114d are not formed.

[0111] According to this manufacturing method, as explained with reference to the graphs in Figures 12 to 14, it is possible to further reduce the voltage drop at the crimping portion 114, and therefore it is possible to provide an electric wire with terminal 100 with improved electrical performance.

[0112] Furthermore, in the manufacturing method for the electric wire with terminal 100, the compression ratio, expressed as the value obtained by multiplying the conductor cross-sectional area of ​​the core wire 102 passing through the crimping portion 114 at a central position in the front-to-rear direction by 100, may be set to 70% or less. In this case, the lower limit of the compression ratio may be set to a value that ensures tensile strength in the crimping portion 114 and does not cause breakage of the core wire 102.

[0113] According to this manufacturing method, as explained with reference to the graphs in Figures 15 to 17, it is possible to further reduce the voltage drop at the crimping portion 114, and therefore it is possible to provide an electric wire with terminal 100 with improved electrical performance.

[0114] Moreover, the electric wire with terminal 100 according to this embodiment has a crimping portion 114 formed by clamping a crimping formation portion 112 of a crimp terminal 110, through which a portion of an electric wire 101 is inserted, between a crimping die 10 consisting of a lower die 14 and an upper die 16. The crimping portion 114 has a lower crimping recess 114c to which a partial convex shape of the lower die 14 is transferred, and an upper crimping recess 114d to which a partial convex shape of the upper die 16 is transferred. It is assumed that the conductor size of the core wire 102 of the electric wire 101 to which the crimping formation portion 112 is crimped is in the range of 40 sq or more and 95 sq or less, and that the wire diameter of the multiple wires constituting the core wire 102 is 0.20 mm or more and 0.80 mm or less. In this case, the recess length L2, which is defined as the length in the front-to-rear direction aligned with the axial direction of the compression forming portion 112 at the bottom surface 114e of each of the lower and upper pressure bonding recesses 114c and 114d, is 6.5 mm or more.

[0115] According to the electric wire with terminal 100, for example, by using the crimping die 10, the recess length L2 at the crimping portion 114 is 6.5 mm or more. Therefore, as described with reference to the graphs in Fig. 11 to Fig. 13, the electric wire with terminal 100 can reduce the voltage drop at the crimping portion 114 when actually used as a product, thereby improving the electrical performance.

[0116] In the electric wire with terminal 100, the rear end of the crimping portion 114 in the front-rear direction may have a rear bell-mouth portion 114j in which the lower crimping recess 114c and the upper crimping recess 114d are not formed.

[0117] According to the electric wire with terminal 100, as explained with reference to the graphs in Figures 12 to 14, the voltage drop at the crimping portion 114 can be reduced, and therefore it is possible to provide an electric wire with terminal 100 with improved electrical performance.

[0118] Furthermore, in the electric wire with terminal 100, with respect to the conductor cross-sectional area of ​​the core wire 102 passing through the middle position in the front-to-rear direction of the crimping portion 114, the compression ratio expressed as the value obtained by multiplying (conductor cross-sectional area after crimping / conductor cross-sectional area before crimping) by 100 may be 70% or less.

[0119] According to the electric wire with terminal 100, as explained with reference to the graphs in Figures 15 to 17, the voltage drop at the crimping portion 114 can be reduced, and therefore it is possible to provide an electric wire with terminal 100 with improved electrical performance.

[0120] In the above description, the crimping die 10 employed in the terminal crimping device 1 has been exemplified, but the structure or shape of the crimping die 10 may also be employed in a crimping tool.

[0121] Although the embodiments relating to each aspect have been described above, the embodiments are not limited to these, and various modifications are possible within the scope of the gist of the embodiments. [Explanation of symbols]

[0122] 10 crimping type 14 Lower mold 16 Upper mold 20a Bottom mold surface 21 Lower mold recess 22 Lower die indentation 22a Lower die central convex part 22c Tip surface 30a Upper mold surface 31 Upper mold concave part 32 Upper die indentation 33 Upper die recess 34 Upper die convex part 100 Wires with terminals 101 Electric wire 110 Crimp terminal 112 Crimping and forming section 114 Crimping section 114c Lower crimp recess 114d Upper crimp recess 114e Bottom L1 indent length L2 Recess length

Claims

1. A crimping die including a lower die and an upper die that crimp a crimping portion of a crimp terminal onto an electric wire when the lower die and the upper die approach each other in the vertical direction, The lower mold and the upper mold each have a rectangular parallelepiped shape whose cross section on a horizontal plane is defined by a front-to-rear direction aligned with the axial direction of the compression forming portion and a width direction perpendicular to the front-to-rear direction, The lower mold and the upper mold are each an indent portion provided in a recessed portion formed on the side of the mold surface facing the crimping direction and contacting the crimping forming portion along the front-rear direction, the indent portion having a central convex portion protruding in the crimping direction; a recess formed adjacent to one end of the indent portion in the width direction and extending from the mold surface in a direction opposite to the crimping direction; a protrusion adjacent to the other end of the indent portion in the width direction and protruding from the mold surface in the crimping direction, When the conductor size of the core wire of the electric wire to which the crimping portion is crimped is in the range of 40 sq or more and 95 sq or less, and the element wire diameters of the plurality of element wires constituting the core wire are 0.20 mm or more and 0.80 mm or less, A crimping mold in which an indent length, defined as the length of the tip surface of the central convex portion of the indent portion in the front-to-rear direction, is 6.5 mm or more.

2. A method for manufacturing an electric wire with a terminal, in which a crimp forming portion of a crimp terminal is crimped to an electric wire, a step of inserting a portion of the electric wire into the crimp forming portion; and a step of sandwiching the crimped portion through which a portion of the electric wire is inserted between a crimping die including a lower die and an upper die, The method for manufacturing an electric wire with a terminal, wherein the crimping die is the crimping die according to claim 1 .

3. the crimped portion formed by being sandwiched by the crimping mold has a crimped recess to which the shape of the central convex portion of the indent portion is transferred, 3. The method for manufacturing an electric wire with terminal according to claim 2, wherein the crimping die clamps the crimp-forming portion so that a rear bell-mouth portion where the crimping recess is not formed is located at a rear end of the crimping portion in the front-to-rear direction.

4. a compression ratio, expressed as a value obtained by multiplying a conductor cross-sectional area of ​​the core wire passing through a middle position in the front-rear direction of the crimping portion by 100 (the conductor cross-sectional area after crimping / the conductor cross-sectional area before crimping), is set to 70% or less; The method for manufacturing an electric wire with a terminal according to claim 3 , wherein the lower limit of the compression rate is set to a value that ensures tensile strength in the crimped portion and does not cause breakage of the core wire.

5. The crimping terminal has a crimping portion formed by sandwiching the crimping portion of the crimp terminal, into which a part of the electric wire is inserted, between a crimping die consisting of a lower die and an upper die, The crimping portion is a lower crimping recess portion to which a convex shape of a part of the lower mold is transferred; an upper compression-bonding recess to which a convex shape of a part of the upper mold is transferred, When the conductor size of the core wire of the electric wire to which the crimping portion is crimped is in the range of 40 sq or more and 95 sq or less, and the element wire diameters of the plurality of element wires constituting the core wire are 0.20 mm or more and 0.80 mm or less, The electric wire with terminal, wherein a recess length defined as the length in the front-to-rear direction aligned with the axial direction of the crimp forming portion at the bottom surface of each of the lower crimping recess and the upper crimping recess is 6.5 mm or more.

6. The electric wire with terminal according to claim 5 , wherein a rear end portion of the crimping portion in the front-rear direction has a rear bell-mouth portion in which the lower crimping recess and the upper crimping recess are not formed.

7. 7. The electric wire with terminal according to claim 6, wherein a compression rate, expressed as a value obtained by multiplying (the conductor cross-sectional area after crimping / the conductor cross-sectional area before crimping) by 100, for a conductor cross-sectional area of ​​the core wire passing through a middle position in the front-to-rear direction of the crimping portion is 70% or less.

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