Method for manufacturing terminal-equipped electric wire, terminal, and terminal-equipped electric wire

Abstract

Provided are a method for manufacturing a terminal-equipped electric wire in which a terminal is crimped to a conductor core wire of an electric wire, a terminal, and a terminal-equipped electric wire. The crimping portion of the terminal has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the shape before crimping is a shape in which the cylindrical inner surface of the crimping portion has a protruding portion protruding into the cylindrical portion. The manufacturing method includes: inserting the conductor core wire into the cylindrical portion of the crimping portion; and crimping the crimping part to the conductor core wire by crimping the crimping part using a crimping tool configured to deform the crimping part into the cylindrical part by pressing the crimping surface against the crimping part.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing an electric wire with a terminal in which a terminal is crimped to a conductor core wire of the electric wire, a terminal, and the electric wire with a terminal. Background Art

[0002] Related art has proposed manufacturing a terminal-attached electric wire by using a terminal, which terminal includes: a connecting portion connected to a mating terminal; and a crimping portion having a continuous cylindrical shape without interruption in the circumferential direction (so-called closed cylindrical shape) and crimped to the conductor core wire of the electric wire (for example, see JP2017-224396A).

[0003] In the above-mentioned type of terminal-equipped electric wire, the riveting surface of the mold used for riveting is usually provided with a protrusion (so-called indentation) for recessing the crimping portion into the cylindrical portion, thereby increasing the contact area and contact pressure between the crimping portion of the terminal and the conductor core wire to improve the reliability of the electrical connection between them (for example, reduce the contact resistance value).

[0004] If the thickness of the cylindrical wall of the crimping portion is small enough relative to the thickness of the conductor core wire, the crimping portion is easily recessed into the cylindrical portion after being crimped by the mold, so that the cylindrical inner surface of the crimping portion is deformed in a manner that protrudes into the cylindrical portion. In this case, the reliability of the electrical connection between the crimping portion and the conductor core wire can be improved. On the other hand, if the thickness of the cylindrical wall of the crimping portion is large relative to the thickness of the conductor core wire, the outer surface of the crimping portion may be deformed after being crimped by the mold, but the tubular inner surface of the crimping portion may not be deformed in a manner that protrudes into the cylindrical portion. In this case, the contact area and contact pressure between the crimping portion and the conductor core wire are insufficient, which makes it difficult to fully improve the reliability of the electrical connection between the crimping portion and the conductor core wire. Summary of the invention

[0005] The present disclosure provides a method for manufacturing an electric wire with a terminal capable of improving the reliability of the electrical connection between the terminal and the electric wire, a terminal capable of improving the reliability of the electrical connection between the terminal and the electric wire, and an electric wire with a terminal capable of improving the reliability of the electrical connection between the terminal and the electric wire.

[0006] The method for manufacturing a terminal-attached electric wire, the terminal, and the terminal-attached electric wire according to the present disclosure are characterized by the following features.

[0007] According to an illustrative aspect of the present disclosure, there is provided a method for manufacturing an electric wire with a terminal, wherein the terminal is crimped to a conductor core wire of the electric wire. The terminal includes a connecting portion to be connected to a mating terminal and a crimping portion to be crimped to the conductor core wire. The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the shape before crimping is a shape in which the cylindrical inner surface of the crimping portion has a protrusion protruding into the cylindrical portion. The manufacturing method includes: inserting the conductor core wire into the cylindrical portion of the crimping portion; and riveting the crimping portion by using a riveting tool to crimp the crimping portion to the conductor core wire, the riveting tool being configured to deform the crimping portion into the cylindrical portion by pressing a riveting surface onto the crimping portion.

[0008] According to another illustrative aspect of the present disclosure, a terminal to be crimped to a conductor core of an electric wire includes: a connection portion to be connected to a mating terminal; and a crimping portion to be crimped to the conductor core. The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the shape before crimping is a shape in which the cylindrical inner surface of the crimping portion has a protrusion protruding into the cylindrical portion.

[0009] According to another illustrative aspect of the present disclosure, a terminal-equipped electric wire comprises: an electric wire; and a terminal crimped to a conductor core wire of the electric wire. The terminal comprises: a connecting portion to be connected to a mating terminal; and a crimping portion crimped to the conductor core wire. The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the cylindrical inner surface of the crimping portion has a shape of multiple curved surfaces protruding from the cylindrical portion. In the cross section, the position where one of the curved surfaces and another of the curved surfaces are connected defines a protrusion protruding into the cylindrical portion of the crimping portion.

[0010] According to the manufacturing method, terminal and wire with terminal of the present invention, the crimping part of the terminal has a continuous cylindrical shape (so-called closed cylindrical shape) without interruption in the circumferential direction, and in the cross section orthogonal to the terminal axis, the shape before crimping is that the cylindrical inner surface of the crimping part has a shape of a protrusion protruding into the cylindrical part. Therefore, when the crimping part is deformed into the cylindrical part using a riveting tool, the crimping part is crimped to the conductor core wire in the shape of the protrusion of the cylindrical inner surface of the crimping part biting the conductor core wire. In addition, the protrusion of the cylindrical inner surface of the crimping part is strongly pressed on the conductor core wire. Therefore, compared with the case where there is no protrusion on the cylindrical inner surface of the crimping part, the contact area and contact pressure between the crimping part and the conductor core wire are increased. This increases the reliability of the electrical connection between the crimping part and the conductor core wire. Therefore, according to the manufacturing method and terminal disclosed in the present invention, a wire with a terminal that can improve the reliability of the electrical connection between the terminal and the wire can be manufactured. According to the wire with a terminal disclosed in the present invention, the reliability of the electrical connection between the terminal and the wire can be improved.

[0011] The present disclosure is briefly described above. The details of the present disclosure can be further clarified by reading the following mode for implementing the present disclosure (hereinafter referred to as "embodiment") with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 : is a side view showing a state in which the electric wire and the terminal included in the electric wire with terminal according to the first embodiment of the present disclosure are separated from each other.

[0013] Figure 2 It is shown Figure 1 The conductor core of the wire shown is inserted Figure 1 A side view showing the state of the cylindrical portion of the crimping portion of the terminal.

[0014] Figure 3 is along Figure 2 Cross-sectional view taken along line AA.

[0015] Figure 4 Shows the use of die riveting Figure 2 The steps of providing a crimping portion of the terminal and crimping the crimping portion to the conductor core wire.

[0016] Figure 5 is with Figure 3 The corresponding cross-sectional view after crimping.

[0017] Figure 6 1 is a side view of a terminal-attached electric wire completed by crimping according to a first embodiment of the present invention.

[0018] Figure 7 The terminal-equipped electric wire according to the second embodiment Figure 3 The corresponding cross-section diagram.

[0019] Figure 8 The terminal-equipped electric wire according to the second embodiment Figure 5 The corresponding cross-section diagram.

[0020] Fig. 9 The terminal-equipped electric wire according to the third embodiment Figure 3 The corresponding cross-section diagram.

[0021] Fig.10 The terminal-equipped electric wire according to the third embodiment Figure 5 The corresponding cross-section diagram.

[0022] Fig.11 The terminal-equipped electric wire according to the fourth embodiment is Figure 3 The corresponding cross-section diagram.

[0023] Fig.12 The terminal-equipped electric wire according to the fourth embodiment is Figure 5 The corresponding cross-section diagram.

[0024] Fig.13 is a side view of a terminal included in the electric wire with terminal according to the fifth embodiment.

[0025] Fig.14 A is along Fig.13 Cross-sectional view taken along line BB.

[0026] Fig.14 B is along Fig.13 Cross-sectional view taken along line CC.

[0027] Fig.14 C is along Fig.13 Cross-sectional view taken along line DD.

[0028] Fig.15 A is Fig.14 A corresponds to the cross-sectional view after crimping.

[0029] Fig.15 B is Fig.14 B corresponds to the cross-sectional view after crimping.

[0030] Fig.15 C is Fig.14 C corresponds to the cross-sectional view after crimping.

[0031] Fig.16 is a side view of a terminal included in the electric wire with terminal according to the sixth embodiment.

[0032] Fig.17 A is along Fig.16 Cross-sectional view taken along line EE.

[0033] Fig.17 B is along Fig.16 A cross-sectional view taken along line FF.

[0034] Fig.17 C is along Fig.16 Cross-sectional view taken along line GG.

[0035] Fig.18 A is Fig.17 A corresponds to the cross-sectional view after crimping.

[0036] Fig.18 B is Fig.17 B corresponds to the cross-sectional view after crimping.

[0037] Fig.18 C is Fig.17 C corresponds to the cross-sectional view after crimping.

[0038] Fig.19 is a side view of a terminal included in the electric wire with terminal according to the seventh embodiment.

[0039] Fig. 20 A is along Fig.19 Cross-sectional view taken along line HH.

[0040] Fig. 20 B is along Fig.19 A cross-sectional view taken along line II.

[0041] Fig. 20 C is along Fig.19 Cross-sectional view taken along the JJ line.

[0042] Fig.21 A is Fig. 20 A corresponds to the cross-sectional view after crimping.

[0043] Fig.21 B is Fig. 20 B corresponds to the cross-sectional view after crimping.

[0044] Fig.21 C is Fig. 20 C corresponds to the cross-sectional view after crimping.

[0045] Fig. 22 is a side view of a terminal included in the electric wire with terminal according to the eighth embodiment.

[0046] Fig.23 A is along Fig. 22 Cross-sectional view taken along line KK.

[0047] Fig.23 B is along Fig. 22 Cross-sectional view taken along the LL line.

[0048] Fig.23 C is along Fig. 22 Cross-sectional view taken along the MM line.

[0049] Fig.24 A is Fig.23 A corresponds to the cross-sectional view after crimping.

[0050] Fig.24 B is Fig.23 B corresponds to the cross-sectional view after crimping.

[0051] Fig.24 C is Fig.23 C corresponds to the cross-sectional view after crimping. DETAILED DESCRIPTION

[0052] <First Embodiment>

[0053] Hereinafter, a terminal-equipped electric wire 1 according to a first embodiment of the present disclosure will be described with reference to the accompanying drawings (see Figure 6 ) manufacturing method. Figure 1 As shown, Figure 6 The illustrated terminal-attached electric wire 1 includes an electric wire 10 and a male terminal 20 . Figure 6 The terminal wire 1 shown is obtained by using Figure 4 The pair of upper and lower dies 30 and 40 shown in the figure rivet the crimping portion 22 (see FIG. Figure 2 and Figure 3 ), and the crimping portion 22 is crimped to the conductor core wire 11. This example uses the male terminal 20, but the female terminal 20 may also be used.

[0054] In the following, for the convenience of description, Figure 1 As shown, the "front-to-back direction", "up-down direction" and "left-to-right direction" are defined. The "front-to-back direction", "up-down direction" and "left-to-right direction" are orthogonal to each other. The front-to-back direction is consistent with the axial direction of the terminal 20. The radial and circumferential directions of the terminal 20 (crimping portion 22) are simply referred to as "radial" and "circumferential". In the following, the components included in the terminal-attached electric wire 1 will be described in sequence first.

[0055] First, the electric wire 10 will be described. Figure 1 As shown, the electric wire 10 includes a rod-shaped (elongated cylindrical) metal conductor core 11 and a cylindrical resin insulating sheath 12 covering the outer circumference of the conductor core 11. The conductor core 11 may be formed by bundling a plurality of conductor wires, or may be formed by only one elongated cylindrical conductor. At the distal end (front end) of the electric wire 10, the insulating sheath 12 is removed by a so-called terminal process to expose the conductor core 11 by a predetermined length.

[0056] Next, the terminal 20 will be described. The metal terminal 20 is formed by casting, cutting, etc. Figure 1 As shown, the terminal 20 is a male terminal and includes a connecting portion 21 near the distal end (front end) and a crimping portion 22 near the base end (rear end). The connecting portion 21 is a portion that is inserted into the base end side of the female mating terminal (not shown) and connected to the mating terminal, and has a solid cylindrical shape extending in the front-to-back direction. The distal end (front end) of the connecting portion 21 has a shape (so-called tapered shape) in which the diameter decreases as it approaches the distal end, so that the connecting portion 21 can be easily inserted into the mating terminal.

[0057] The crimping portion 22 is a portion that is inserted from the rear side into the exposed conductor core 11 of the electric wire 10 and crimped to the conductor core 11, and has a substantially hollow cylindrical shape extending in the front-to-back direction and having a closed front end and an open rear end before crimping (see Figure 1 and Figure 3 ). In other words, the crimping portion 22 has a continuous cylindrical shape without interruption in the circumferential direction (so-called closed cylindrical shape). The base end (rear end) of the cylindrical inner surface 25 of the crimping portion 22 has a shape whose diameter increases as it approaches the base end (so-called trumpet shape), so that the conductor core wire 11 of the electric wire 10 can be easily inserted into the crimping portion 22.

[0058] Hereinafter, the cross section perpendicular to the front-to-rear direction of the crimping portion 22 (the cross section perpendicular to the axis of the terminal 20) is referred to as a "cross section". Figure 1 ) has a simple cylindrical outer peripheral surface shape, and the cross section of the outer surface 24 is circular (see Figure 3 On the other hand, before crimping, in addition to the base end, the cylindrical inner surface 25 of the crimping portion 22 has a shape including a protruding strip, i.e., a protrusion 27, which protrudes radially inward (into the cylindrical portion) and extends in the front-rear direction. More specifically, as Figure 3 As shown, the cylindrical inner surface 25 of the crimping portion 22 has a shape in which two circles 26 are partially overlapped with each other in cross section, and the overlapping positions (two positions) of the two circles 26 each have a protrusion 27. The two circles 26 have the same radius. The centers p of the two circles 26 are respectively located at positions at the same distance from the center O on two line segments L extending radially outward from the center O of the circular outer surface 24 and bisecting the circumference.

[0059] Except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-rear direction) of the terminal 20. The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, cutting with a drill. Specifically, the cylindrical inner surface 25 can be formed by configuring a drill having an outer diameter equal to or less than the diameter of the circle 26 so that its axis is parallel to the axial direction of the terminal 20, and inserting the drill from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed for cutting. If a drill having an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 can be formed by inserting the drill only twice into the crimping portion 22 before the cylindrical inner surface 25 is formed, corresponding to the two circles 26.

[0060] like Figure 1 As shown, the boundary between the connection portion 21 and the crimping portion 22 is provided with the annular and flat plate-like flange 23 extending radially outward over the entire area in the circumferential direction. The respective components included in the electric wire with terminal 1 have been described in sequence.

[0061] Next, we will refer to Figure 4 A pair of upper and lower molds 30, 40 used when riveting the crimping portion 22 of the terminal 20 into which the conductor core wire 11 of the electric wire 10 is inserted is described. The pair of upper and lower molds 30, 40 are configured so that the entire riveting surface has a hexagonal cross-sectional shape when clamped. Therefore, the riveting surface 31 of the upper mold 30 has a cross-sectional shape of the upper half of the hexagon, and the riveting surface 41 of the lower mold 40 has a cross-sectional shape of the lower half of the hexagon. In addition, the central portion of the riveting surface 31 of the upper mold 30 in the left and right directions is provided with a protruding strip, i.e., a protrusion 32 (so-called indentation), which protrudes downward (i.e., enters the cylindrical portion of the crimping portion 22) and extends in the front-to-back direction, thereby recessing the crimping portion 22 into the cylindrical portion of the crimping portion 22. Similarly, a protruding strip, i.e., a protrusion 42, is provided at the central portion in the left-right direction of the riveting surface 41 of the lower die 40, which protrudes upward (i.e., enters the cylindrical portion of the crimping portion 22) and extends in the front-rear direction, thereby recessing the crimping portion 22 into the cylindrical portion of the crimping portion 22. The upper and lower protrusions 32, 42 are opposite to each other in the upper-lower direction.

[0062] Next, we will describe Figure 6 To manufacture the electric wire with terminal 1, first, the exposed conductor core wire 11 of the electric wire 10 is inserted into the crimping portion 22 of the terminal 20 from the rear side (see Figure 1 and Figure 2). When the insertion is completed, the exposed conductor core wire 11 of the electric wire 10 is accommodated in the cylindrical portion of the crimping portion 22. The conductor core wire 11 only needs to be inserted into the cylindrical portion of the crimping portion 22 to a position suitable for crimping (the details will be described later). The distal end face (front end face) of the insulating sheath 12 of the electric wire 10 can be in contact with the base end face (rear end face) of the crimping portion 22, or the distal end face (front end face) of the insulating sheath 12 of the electric wire 10 can be separated from the base end face (rear end face) of the crimping portion 22.

[0063] Next, if Figure 4 As shown, the upper mold 30 and the lower mold 40 are respectively arranged above and below the crimping portion 22 of the terminal 20 into which the conductor core wire 11 of the electric wire 10 is inserted. Next, the upper and lower molds 30 and 40 are relatively close to each other in the vertical direction, so that the crimping portion 22 is sandwiched between the upper and lower molds 30 and 40 in the vertical direction. As a result, the rivet surface 31 including the protrusion 32 of the mold 30 and the rivet surface 41 including the protrusion 42 of the mold 40 are pressed against the crimping portion 22. Therefore, as shown in FIG. Figure 5 As shown in FIG. 1 , the crimping portion 22 is deformed and riveted into the cylindrical portion, thereby crimping the crimping portion 22 to the conductor core wire 11 of the electric wire 10. Figure 6 As shown, the electric wire with terminal 1 is manufactured in which the caulking position Y is formed in a part of the crimping portion 22 in the front-rear direction.

[0064] like Figure 5 As shown, the outer surface 24 of the crimping portion 22 after crimping has a hexagonal cross-sectional shape corresponding to the cross-sectional shape formed by the riveting surfaces 31, 41 of the dies 30, 40. In addition, the positions on the outer surface 24 after crimping corresponding to the protrusions 32, 42 on the riveting surfaces 31, 41 are engaged by the protrusions 32, 42, thereby forming recesses 28, 29. Compared with the cylindrical inner surface 25 before crimping, the cylindrical inner surface 25 of the crimping portion 22 after crimping has a cross-sectional shape that is compressed in the up and down directions. More specifically, after crimping, the crimping portion 22 has a continuous cylindrical shape without interruption in the circumferential direction, and in Figure 5The cylindrical inner surface 25 having the crimping portion 22 in the cross section shown has a shape of multiple curved surfaces protruding outward from the cylindrical portion. The position where one curved surface and another curved surface are connected defines a protrusion 27 protruding into the cylindrical portion of the crimping portion 22. In addition, the protrusion 27 (two positions) of the cylindrical inner surface 25 bites the conductor core wire 11 of the electric wire 10. Therefore, the protrusion 27 (two positions) of the crimping portion 22 is strongly pressed against the conductor core wire 11. Therefore, even if the thickness of the cylindrical wall of the crimping portion 22 is relatively large, the contact area and contact pressure between the crimping portion 22 and the conductor core wire 11 are increased compared to the case where the cylindrical inner surface 25 of the crimping portion 22 is not provided with the protrusion 27. In addition, due to the engagement of the protrusions 32 and 42 (due to the formation of recesses 28 and 29 on the outer surface 24), the crimping portion 22 is recessed into the cylindrical portion, so that the crimping portion 22 is crimped to the conductor core wire 11 of the electric wire 10 in a shape in which the protrusion 27 of the cylindrical inner surface 25 more deeply engages with the conductor core wire 11, and the protrusion 27 of the cylindrical inner surface 25 is pressed more strongly against the conductor core wire.

[0065] <Second Embodiment>

[0066] In the first embodiment, in order to make the cylindrical inner surface 25 of the crimping portion 22 have a shape with the protrusion 27, as shown in FIG. Figure 3 As shown, the cylindrical inner surface 25 has a shape in cross section in which two circles 26 are combined while partially overlapping each other, and the overlapping positions (two positions) of the two circles 26 each have a protrusion 27 .

[0067] On the other hand, in the second embodiment, in order to make the cylindrical inner surface 25 of the crimping portion 22 have a shape with the protrusion 27, as shown in FIG. Figure 7 As shown, the cylindrical inner surface 25 may have a shape in cross section in which three circles 26 are combined in such a manner that every two circles 26 adjacent in the circumferential direction partially overlap each other, and the overlapping positions (three positions) of the three circles 26 each have a protrusion 27. In this case, the three circles 26 have the same radius. The centers p of the three circles 26 are respectively located at the same distance from the center O on three line segments L extending radially outward from the center O of the circular outer surface 24 and dividing the circumference into three equal parts.

[0068] Also in the second embodiment, except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-rear direction) of the terminal 20. The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill having an axis parallel to the axial direction of the terminal 20 and an outer diameter equal to or smaller than the diameter of the circle 26, and inserting the drill from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed to perform cutting. If a drill having an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 can be formed by inserting the drill only three times into the crimping portion 22 before the cylindrical inner surface 25 is formed, corresponding to the three circles 26.

[0069] Also in this case, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Figure 8 As shown, the protrusions 27 (three locations) of the cylindrical inner surface 25 bite the conductor core wire 11 of the electric wire 10. Therefore, the protrusions 27 (three locations) of the crimping portion 22 are strongly pressed against the conductor core wire 11.

[0070] <Third Embodiment>

[0071] Likewise, in the third embodiment, in order to make the cylindrical inner surface 25 of the crimping portion 22 have a shape with a protrusion 27, as shown in FIG. Fig. 9 As shown, the cylindrical inner surface 25 may have a shape in cross section in which four circles 26 are combined in such a manner that every two circles 26 adjacent in the circumferential direction partially overlap each other, and the overlapping positions (four positions) of the four circles 26 respectively constitute the protrusions 27. In this case, the four circles 26 have the same radius. The centers p of the four circles 26 are respectively located at positions at the same distance from the center O on four line segments L extending radially outward from the center O of the circular outer surface 24 and dividing the circumference into four equal parts.

[0072] Also in the third embodiment, except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-rear direction) of the terminal 20. The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill having an axis parallel to the axial direction of the terminal 20 and an outer diameter equal to or smaller than the diameter of the circle 26, and inserting the drill from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed to perform cutting. If a drill having an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 can be formed by inserting the drill only four times into the crimping portion 22 before the cylindrical inner surface 25 is formed, corresponding to four circles 26.

[0073] Also in this case, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.10 As shown, the protrusions 27 (four locations) of the cylindrical inner surface 25 bite the conductor core wire 11 of the electric wire 10. Therefore, the protrusions 27 (four locations) of the crimping portion 22 are strongly pressed against the conductor core wire 11.

[0074] <Fourth Embodiment>

[0075] Likewise, in the fourth embodiment, in order to make the cylindrical inner surface 25 of the crimping portion 22 have a shape with a protrusion 27, as shown in FIG. Fig.11 As shown, the cylindrical inner surface 25 may have a shape in cross section in which a large circle 51 centered at the center O of the outer surface 24 and four small circles 26 arranged at intervals in the circumferential direction around the large circle 51 are combined in such a way that the large circle 51 and the four small circles 26 partially overlap, and the overlapping positions (eight positions) of the large circle 51 and the four small circles 26 each have a protrusion 27. In this case, the four circles 26 have the same radius. The centers p of the four circles 26 are respectively located at positions at the same distance from the center O on four line segments L extending radially outward from the center O of the circular outer surface 24 and dividing the circumference into four equal parts.

[0076] Also in the fourth embodiment, except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-rear direction) of the terminal 20. The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill having an axis parallel to the axial direction of the terminal 20 and an outer diameter equal to or smaller than the diameter of the circle 26, and inserting the drill from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed to perform cutting. If a first drill having an outer diameter equal to the diameter of the circle 51 and a second drill having an outer diameter equal to the diameter of the circle 26 are used, the cylindrical inner surface 25 of the crimping portion 22 can be formed by only inserting the first drill once to correspond to the circle 51 and inserting the second drill four times to correspond to the four circles 26 into the crimping portion 22 before the cylindrical inner surface 25 is formed.

[0077] Also in this case, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.12 As shown, the protrusions 27 (eight locations) of the cylindrical inner surface 25 bite the conductor core wire 11 of the electric wire 10. Therefore, the protrusions 27 (eight locations) of the crimping portion 22 are strongly pressed against the conductor core wire 11.

[0078] <Fifth Embodiment>

[0079] In the first embodiment, if Figure 3As shown, in the cylindrical inner surface 25 of the crimping portion 22 of the terminal 20, the overlapping positions (two positions) of the two circles 26 respectively have protrusions 27, and except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-to-back direction) of the terminal 20. In other words, except for the above-mentioned base end portion, in the cross section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the two circles 26 is constant, regardless of the position in the axial direction (front-to-back direction) of the terminal 20.

[0080] on the other hand, Figures 13 to 15 The fifth embodiment shown in C is similar to the first embodiment in that the overlapping positions (two positions) of the two circles 26 on the cylindrical inner surface 25 of the crimping portion 22 respectively have protrusions 27, and is different from the first embodiment in that, in the cross-section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the two circles 26 varies according to the position of the terminal 20 in the axial direction (front-to-back direction).

[0081] Specifically, in the fifth embodiment, if Fig.13 As shown, the crimping portion 22 of the terminal 20 includes a base end portion 22A and a distal end portion 22B which is arranged with the base end portion 22A in the axial direction of the terminal 20 and is continuous with the distal end side (front end side) of the base end portion 22A. The cylindrical inner space of the base end portion 22A and the cylindrical inner space of the distal end portion 22B are located at a boundary position z between the base end portion 22A and the distal end portion 22B (see Fig.13 ) are adjacent to each other and connected. Fig.14 A and Fig.14 By comparison of C, it can be understood that the position (two positions) of the protrusion 27 on the cylindrical inner surface 25 of the base end portion 22A and the position (two positions) of the protrusion 27 on the cylindrical inner surface 25 of the distal end portion 22B coincide with each other in the circumferential direction (the direction surrounding the axis of the terminal 20).

[0082] In the base end portion 22A, as shown in FIG. Fig.13 and Fig.14 As shown in FIG. 1A, as the position in the axial direction (front-rear direction) of the terminal 20 approaches the base end side (rear end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the two circles 26 increases linearly from zero. In the distal end portion 22B, as shown in FIG. Fig.13 and Fig.14As shown in C, as the position in the axial direction (front-to-back direction) of the terminal 20 approaches the distal side (front end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the two circles 26 increases linearly from zero. In other words, the base end portion 22A has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the front end portion 22B, and the distal end portion 22B has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the base end portion 22A. The cylindrical internal space of the base end portion 22A and the cylindrical internal space of the distal end portion 22B are adjacent to and connected to each other. As a result, as shown in Fig.13 As shown, the cylindrical internal space is locally narrowed at the boundary position z, and the cylindrical inner surface 25 at the boundary position z has a shape having a protruding strip, i.e., a protrusion 27A, which protrudes radially inward (into the cylindrical portion) and extends around the entire circumference (in the direction around the axis of the terminal 20).

[0083] The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill bit whose axis is inclined relative to the axial direction of the terminal 20 and whose outer diameter is equal to or smaller than the diameter of the circle 26, and inserting the drill bit from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed for cutting.

[0084] Specifically, the cylindrical inner surface 25 may be formed by forming a circular shape 26A (see FIG. 26A ) in the cross section of the base end portion 22A. Fig.14 A) and the circular shape 26A in the cross section of the distal end portion 22B (see Fig.14 C), a drill having an axis inclined to the right at the base end side (rear end side) and inclined to the left at the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted from the rear side into the crimping portion 22 to cut, thereby forming. In addition, the circle 26B (see FIG. 26B ) in the cross section of the base end portion 22A can be formed. Fig.14 A) and the circular shape 26B in the cross section of the distal end portion 22B (see Fig.14 C) is disposed at a position corresponding to the terminal 20, and its axis is inclined to the left on the base end side (rear end side) and to the right on the distal end side (front end side) with respect to the axis direction of the terminal 20, and a drill bit with an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill bit is inserted into the crimping portion 22 from the rear side for cutting, thereby forming. If a drill bit with an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 (which means the combination of the portion 22A and the distal end portion 22B) can be formed by inserting the drill bit into the crimping portion 22 only twice, corresponding to the two circles 26.

[0085] Also in the fifth embodiment, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.15As shown in FIGS. 1A to 15C, the protrusions 27 (two locations) of the cylindrical inner surface 25 bite the conductor core 11 of the electric wire 10 at the base end portion 22A and the distal end portion 22B. Therefore, the protrusions 27 (two locations) of the crimping portion 22 are strongly pressed against the conductor core 11. In addition, at the boundary position z between the base end portion 22A and the distal end portion 22B, the protrusions 27A (see FIG. 15C) of the cylindrical inner surface 25 are pressed against the conductor core 11. Fig.13 ) also bites the conductor core wire 11 of the electric wire 10. In addition, the cylindrical inner surface 25 is inclined relative to the conductor core wire 11, thereby increasing the contact area between the cylindrical inner surface 25 and the conductor core wire 11. This further improves the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11.

[0086] <Sixth Embodiment>

[0087] In the second embodiment, if Figure 7 As shown, in the cylindrical inner surface 25 of the crimping portion 22 of the terminal 20, the overlapping positions (three positions) of the three circles 26 respectively have protrusions 27, and except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-to-back direction) of the terminal 20. In other words, except for the above-mentioned base end portion, in the cross section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the three circles 26 is constant, regardless of the position in the axial direction (front-to-back direction) of the terminal 20.

[0088] on the other hand, Figures 16 to 18 The sixth embodiment shown in C is similar to the second embodiment in that the overlapping positions (three positions) of the three circles 26 on the cylindrical inner surface 25 of the crimping portion 22 respectively have protrusions 27, and is different from the second embodiment in that, in the cross-section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the three circles 26 varies according to the position of the terminal 20 in the axial direction (front-to-back direction).

[0089] Specifically, in the sixth embodiment, the same as the fifth embodiment, Fig.16 As shown, the crimping portion 22 of the terminal 20 includes a base end portion 22A and a distal end portion 22B. The cylindrical inner space of the base end portion 22A and the cylindrical inner space of the distal end portion 22B are located at a boundary position z between the base end portion 22A and the distal end portion 22B (see Fig.16 ) are adjacent to each other and connected. Fig.17 A and Fig.17 By comparison with C, it can be understood that the respective positions (three positions) of the protrusions 27 on the cylindrical inner surface 25 of the base end portion 22A and the respective positions (three positions) of the protrusions 27 on the cylindrical inner surface 25 of the distal end portion 22B are offset by 180 degrees in the circumferential direction (the direction surrounding the axis of the terminal 20).

[0090] In the base end portion 22A, as shown in FIG. Fig.16 and 17 As shown in FIG. 1A, as the position in the axial direction (front-rear direction) of the terminal 20 approaches the base end side (rear end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the three circles 26 increases linearly from zero. In the distal end portion 22B, as shown in FIG. Fig.16 and Fig.17 As shown in C, as the position in the axial direction (front-to-back direction) of the terminal 20 approaches the distal side (front end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the two circles 26 increases linearly from zero. In other words, the base end portion 22A has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the distal end portion 22B, and the distal end portion 22B has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the base end portion 22A. The cylindrical internal space of the base end portion 22A and the cylindrical internal space of the distal end portion 22B are adjacent to and connected to each other. As a result, as shown in Fig.16 As shown, the cylindrical internal space is locally narrowed at the boundary position z, and the cylindrical inner surface 25 at the boundary position z has the shape of a protruding strip, i.e., a protrusion 27A, as shown in the fifth embodiment, which protrudes radially inward (into the cylindrical portion) and extends around the entire circumference in the circumferential direction (in the direction around the axis of the terminal 20).

[0091] The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill bit whose axis is inclined relative to the axial direction of the terminal 20 and whose outer diameter is equal to or smaller than the diameter of the circle 26, and inserting the drill bit from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed for cutting.

[0092] Specifically, the cylindrical inner surface 25 may be formed by forming a circular shape 26A (see FIG. 26A ) in the cross section of the base end portion 22A. Fig.17 A) and the circular shape 26A in the cross section of the distal end portion 22B (see Fig.17 C), a drill having an axis inclined to the upper right at the base end side (rear end side) and inclined to the lower left at the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted from the rear side into the crimping portion 22 to cut, thereby forming. In addition, the circle 26B (see FIG. 26B ) in the cross section of the base end portion 22A can be formed. Fig.17 A) and the circular shape 26B in the cross section of the distal end portion 22B (see Fig.17C), a drill having an axis inclined to the upper left at the base end side (rear end side) and inclined to the lower right at the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted into the crimping portion 22 from the rear side to cut, thereby forming. In addition, the circle 26C (see FIG. 26C ) in the cross section of the base end portion 22A can be formed. Fig.17 A) and the circular shape 26C in the cross section of the distal end portion 22B (see Fig.17 C) at the corresponding position, a drill having an axis that is inclined downward on the base end side (rear end side) and upward on the distal end side (front end side) relative to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted into the crimping portion 22 from the rear side to cut, thereby forming. If a drill having an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 (which means the combination of the base end portion 22A and the distal end portion 22B) can be formed by inserting the drill into the crimping portion 22 only three times corresponding to the three circles 26.

[0093] Also in the sixth embodiment, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.18 As shown in FIGS. 1A to 18C, the protrusions 27 (three positions) of the cylindrical inner surface 25 bite the conductor core wire 11 of the electric wire 10 at the base end portion 22A and the distal end portion 22B. Therefore, the protrusions 27 (three positions) of the crimping portion 22 are strongly pressed against the conductor core wire 11. In addition, at the boundary position z between the base end portion 22A and the distal end portion 22B, the protrusions 27A (see FIG. 18C) of the cylindrical inner surface 25 are pressed against the conductor core wire 11. Fig.16 ) also bites the conductor core wire 11 of the electric wire 10. This further improves the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11. In addition, the respective positions (three positions) of the protrusions 27 on the cylindrical inner surface 25 of the base end portion 22A and the respective positions (three positions) of the protrusions 27 on the cylindrical inner surface 25 of the distal end portion 22B are different from each other in the circumferential direction (the direction around the axis of the terminal 20). As a result, the protrusions 27 of the base end portion 22A and the protrusions 27 of the distal end portion bite the conductor core wire 11 from different positions in the direction around the axis of the terminal 20. This uniformly increases the contact area and contact pressure between the crimping portion 22 and the conductor core wire 11 in the direction around the axis of the terminal 20, thereby further improving the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11.

[0094] <Seventh Embodiment>

[0095] In the third embodiment, if Fig. 9As shown, in the cylindrical inner surface 25 of the crimping portion 22 of the terminal 20, the overlapping positions (four positions) of the four circles 26 respectively have protrusions 27, and except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 20 has the same shape in the entire axial direction (front-to-back direction) of the terminal 20. In other words, except for the above-mentioned base end portion, in the cross section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the four circles 26 is constant, regardless of the position in the axial direction (front-to-back direction) of the terminal 20.

[0096] on the other hand, Figures 19 to 21 The seventh embodiment shown in C is similar to the third embodiment in that the overlapping positions (four positions) of the four circles 26 on the cylindrical inner surface 25 of the crimping portion 22 respectively have protrusions 27, and is different from the third embodiment in that the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the four circles 26 varies according to the position of the terminal 20 in the axial direction (front-to-back direction).

[0097] Specifically, in the seventh embodiment, the same as the fifth embodiment, Fig.19 As shown, the crimping portion 22 of the terminal 20 includes a base end portion 22A and a distal end portion 22B. The cylindrical inner space of the base end portion 22A and the cylindrical inner space of the distal end portion 22B are located at a boundary position z between the base end portion 22A and the distal end portion 22B (see Fig.19 ) are adjacent to each other and connected. Fig. 20 A and Fig. 20 From the comparison of C, it can be understood that the respective positions (four positions) of the protrusions 27 on the cylindrical inner surface 25 of the base end portion 22A and the respective positions (four positions) of the protrusions 27 on the cylindrical inner surface 25 of the distal end portion 22B coincide with each other in the circumferential direction (the direction surrounding the axis of the terminal 20).

[0098] In the base end portion 22A, as shown in FIG. Fig.19 and Fig. 20 As shown in FIG. 1A, as the position of the terminal 20 in the axial direction (front-rear direction) approaches the base end side (rear end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the four circles 26 increases linearly from zero. In the distal end portion 22B, as shown in FIG. Fig.19 and 20As shown in C, as the position in the axial direction (front-to-back direction) of the terminal 20 approaches the distal side (front end side) from the boundary position z, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of the four circles 26 gradually increases from zero. In other words, the base end portion 22A has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the distal end portion 22B, and the distal end portion 22B has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the base end portion 22A. The cylindrical internal space of the base end portion 22A and the cylindrical internal space of the distal end portion 22B are adjacent to and connected to each other. As a result, as shown in Fig.19 As shown, the cylindrical internal space is locally narrowed at the boundary position z, and the cylindrical inner surface 25 at the boundary position z has the shape of a protruding strip, i.e., a protrusion 27A, as shown in the fifth embodiment, which protrudes radially inward (into the cylindrical portion) and extends around the entire circumference in the circumferential direction (in the direction around the axis of the terminal 20).

[0099] The cylindrical inner surface 25 of the crimping portion 22 can be formed by, for example, configuring a drill bit whose axis is inclined relative to the axial direction of the terminal 20 and whose outer diameter is equal to or smaller than the diameter of the circle 26, and inserting the drill bit from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed for cutting.

[0100] Specifically, the cylindrical inner surface 25 may be formed by forming a circular shape 26A (see FIG. 26A ) in the cross section of the base end portion 22A. Fig. 20 A) and the circular shape 26A in the cross section of the distal end portion 22B (see Fig. 20 C), a drill having an axis inclined to the upper right at the base end side (rear end side) and inclined to the lower left at the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted from the rear side into the crimping portion 22 to cut, thereby forming. In addition, the circle 26B (see FIG. 26B ) in the cross section of the base end portion 22A can be formed. Fig. 20 A) and the circular shape 26B in the cross section of the distal end portion 22B (see Fig. 20 C), a drill having an axis inclined to the upper left on the base end side (rear end side) and inclined to the lower right on the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted into the crimping portion 22 from the rear side to cut, thereby forming. In addition, the circle 26C (see FIG. 26A ) in the cross section of the base end portion 22A can be formed. Fig. 20 A) and the circular shape 26C in the cross section of the distal end portion 22B (see Fig. 20C), a drill having an axis inclined downward to the left at the base end side (rear end side) and upward to the right at the distal end side (front end side) with respect to the axis direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted from the rear side into the crimping portion 22 for cutting, so as to form. In addition, the circle 26D (see FIG. 26D ) in the cross section of the base end portion 22A can be formed. Fig. 20 A) and the circular shape 26D in the cross section of the distal end portion 22B (see Fig. 20 C) at the corresponding position, a drill having an axis inclined to the lower right on the base end side (rear end side) and inclined to the upper left on the distal end side (front end side) with respect to the axial direction of the terminal 20 and having an outer diameter equal to or smaller than the diameter of the circle 26 is arranged, and the drill is inserted into the crimping portion 22 from the rear side to cut, thereby forming. If a drill having an outer diameter equal to the diameter of the circle 26 is used, the cylindrical inner surface 25 of the crimping portion 22 (which means the combination of the base end portion 22A and the distal end portion 22B) can be formed by inserting the drill into the crimping portion 22 only four times corresponding to the four circles 26.

[0101] Also in the seventh embodiment, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.21 As shown in FIG. 1 , the protrusions 27 (four locations) of the cylindrical inner surface 25 bite the conductor core 11 of the electric wire 10 at the distal end portion 22B and the base end portion 22A. Therefore, the protrusions 27 (four locations) of the crimping portion 22 are strongly pressed against the conductor core 11. In addition, at the boundary position z between the distal end portion 22B and the base end portion 22A, the protrusions 27A (see FIG. 1 ) of the cylindrical inner surface 25 are pressed against the conductor core 11. Fig.19 ) also bites the conductor core wire 11 of the electric wire 10. This further improves the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11.

[0102] <Eighth Embodiment>

[0103] In the fourth embodiment, if Fig.11 As shown, in the cylindrical inner surface 25 of the crimping portion 22 of the terminal 20, the overlapping positions (eight positions) of a large circle 51 and four small circles 26 respectively have protrusions 27, and except for the above-mentioned base end portion, the cylindrical inner surface 25 of the crimping portion 22 has the same shape in the entire axial direction (front-to-back direction) of the terminal 20. In other words, except for the above-mentioned base end portion, in the cross section of the cylindrical inner surface 25 of the crimping portion 22, the distance between the center O and the center p of each of the four circles 26 is constant, regardless of the position in the axial direction (front-to-back direction) of the terminal 20.

[0104] on the other hand, Figures 22 to 24The eighth embodiment shown in C is similar to the fourth embodiment in that a large circle 51 and four small circles 26 on the cylindrical inner surface 25 of the crimping portion 22 have protrusions 27 at the overlapping positions (eight positions), and is different from the fourth embodiment in that the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the four circles 26 varies according to the position of the terminal 20 in the axial direction (front-to-back direction).

[0105] Specifically, if Fig. 22 As shown, the eighth embodiment is different from the fifth to seventh embodiments in that, in the crimping portion 22 of the terminal 20, the middle portion 22C is placed between the base end portion 22A and the distal end portion 22B, and the crimping portion 22 of the terminal 20 is formed by the base end portion 22A, the middle portion 22C and the distal end portion 22B arranged from the base end side to the distal end side along the axial direction of the terminal 20. The cylindrical inner space of the base end portion 22A and the cylindrical inner space of the middle portion 22C are at the boundary position z1 between the base end portion 22A and the middle portion 22C (see Fig. 22 ) are adjacent to each other and connected. The cylindrical inner space of the distal end portion 22B and the cylindrical inner space of the middle portion 22C are located at the boundary position z2 between the distal end portion 22B and the middle portion 22C (see Fig. 22 ) are adjacent to each other and connected. Fig.23 A to Fig.23 C It can be understood that the cylindrical inner surface 25 is formed with protrusions 27 (eight positions) in both the base end portion 22A and the distal end portion 22B, but no protrusion 27 is formed in the middle portion 22C. In the middle portion 22C, the cross section of the cylindrical inner surface 25 is formed by only a large circle 51 extending in the entire axial direction (front-rear direction) of the terminal 20 (see Fig.23 B) From Fig.23 A and Fig.23 From the comparison of C, it can be understood that the respective positions (eight positions) of the protrusions 27 on the cylindrical inner surface 25 of the base end portion 22A and the respective positions (eight positions) of the protrusions 27 on the cylindrical inner surface 25 of the distal end portion 22B coincide with each other in the circumferential direction (the direction surrounding the axis of the terminal 20).

[0106] In the base end portion 22A, as shown in FIG. Fig. 22 and Fig.23 As shown in FIG. 1A, as the position of the terminal 20 in the axial direction (front-rear direction) approaches the base end side (rear end side) from the boundary position z1, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the four circles 26 increases linearly from zero. In the distal end portion 22B, as shown in FIG. Fig. 22 and Fig.23As shown in C, as the position of the terminal 20 in the axial direction (front-to-back direction) approaches the distal side (front end side) from the boundary position z2, the distance between the center O in the cross section of the cylindrical inner surface 25 of the crimping portion 22 and the center p of each of the four circles 26 gradually increases from zero. In other words, the base end portion 22A has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the distal end portion 22B, and the distal end portion 22B has a shape in which the cross-sectional area of ​​the cylindrical internal space decreases as it approaches the base end portion 22A. The cylindrical internal space of the base end portion 22A and the cylindrical internal space of the distal end portion 22B are connected to each other via the cylindrical internal space of the middle portion 22C. As a result, as shown in FIG. Fig. 22 As shown, at each position on the circumference (the direction around the axis of the terminal 20) where the four circles 26 are located at the boundary position z1 and the boundary position z2, the cylindrical inner surface 25 has a shape having a protruding strip, i.e., a protrusion 27A, which protrudes radially inward (into the cylindrical portion) and extends in the circumferential direction (the direction around the axis of the terminal 20).

[0107] The cylindrical inner surface 25 of the crimping portion 22 can be formed in the following manner: for example, a first drill bit is configured with its axis parallel to the axial direction of the terminal 20 and its outer diameter is equal to or smaller than the diameter of the circle 51, and the drill bit is inserted from the rear into the (solid) crimping portion 22 before the cylindrical inner surface 25 is formed for cutting, and a second drill bit is configured with its axis inclined relative to the axial direction of the terminal 20 and its outer diameter is equal to or smaller than the diameter of the circle 26, and the drill bit is inserted from the rear into the crimping portion 22 before the cylindrical inner surface 25 is formed for cutting.

[0108] Specifically, first, by using a first drill, a cylindrical hole having a circular cross section 51 is formed on the entire base end portion 22A, the middle portion 22C, and the distal end portion 22B along the axial direction of the terminal 20, thereby forming a cylindrical inner surface 25 of the middle portion 22C as a part of the cylindrical hole in the axial direction. Specifically, the cylindrical inner surface 25 can be formed by drilling a circular cross section 26A (see FIG. 5A ) on the cylindrical inner surface 25 that is in line with the cross section of the base end portion 22A. Fig.23 A) and the circular shape 26A in the cross section of the distal end portion 22B (see Fig.23 C), a second drill bit is arranged at a position corresponding to the axial direction of the terminal 20, and its axis is inclined to the upper right on the base end side (rear end side) and to the lower left on the distal end side (front end side), and the drill bit is inserted into the crimping portion 22 from the rear side to cut, thereby forming. In addition, the circular shape 26B (see FIG. 26B ) in the cross section of the base end portion 22A can be formed. Fig.23 A) and the circular shape 26B in the cross section of the distal end portion 22B (see Fig.23C), a second drill bit is arranged whose axis is inclined to the upper left on the base end side (rear end side) and to the lower right on the distal end side (front end side) relative to the axis direction of the terminal 20, and the drill bit is inserted into the crimping portion 22 from the rear side to cut, thereby forming. In addition, the circular shape 26C (see FIG. 26A ) in the cross section of the base end portion 22A can be formed. Fig.23 A) and the circular shape 26C in the cross section of the distal end portion 22B (see Fig.23 C), a second drill bit is arranged at a position corresponding to the axial direction of the terminal 20, and its axis is inclined to the lower left on the base end side (rear end side) and to the upper right on the distal end side (front end side), and the drill bit is inserted into the crimping portion 22 from the rear side to cut, thereby forming. In addition, the circular shape 26D (see FIG. 26D ) in the cross section of the base end portion 22A can be formed. Fig.23 A) and the circular shape 26D in the cross section of the distal end portion 22B (see Fig.23 C) at a position corresponding to the terminal 20, a second drill whose axis is inclined to the lower right on the base end side (rear end side) and to the upper left on the distal end side (front end side) relative to the axis direction of the terminal 20 is arranged, and the drill is inserted into the crimping portion 22 from the rear side to cut, thereby forming. If a first drill having an outer diameter equal to the diameter of the circle 51 and a second drill having an outer diameter equal to the diameter of the circle 26 are used, the cylindrical inner surface 25 of the crimping portion 22 (which means a combination of the base end portion 22A, the middle portion 22C, and the distal end portion 22B) can be formed by inserting the first drill once to correspond to the circle 51 and inserting the second drill four times to correspond to the four circles 26 into the crimping portion 22 before the cylindrical inner surface 25 is formed.

[0109] Also in the eighth embodiment, when using Figure 4 After the upper and lower molds 30 and 40 are crimped, Fig.24 As shown in FIGS. 24A to 24C, the protrusions 27 (eight locations) of the cylindrical inner surface 25 bite the conductor core 11 of the electric wire 10 at the base end portion 22A and the distal end portion 22B. Therefore, the protrusions 27 (eight locations) of the crimping portion 22 are strongly pressed against the conductor core 11. In addition, at the boundary position z1 between the base end portion 22A and the middle portion 22C and the limit position z2 between the distal end portion 22B and the middle portion 24C, the protrusions 27A (see FIG. 24B ) of the cylindrical inner surface 25 are pressed against the conductor core 11. Fig. 22 ) also bites the conductor core wire 11 of the electric wire 10. This further improves the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11.

[0110] <Operation and Effect>

[0111] As described above, according to the manufacturing method of the electric wire with terminal 1, the terminal 20, and the electric wire with terminal 1 of the present embodiment, the crimping portion 22 of the terminal 20 has a continuous cylindrical shape without interruption in the circumferential direction, and at a cross section orthogonal to the axis (front-rear direction) of the terminal 20, the cylindrical inner surface 25 of the crimping portion 22 has a shape before crimping of the protrusion 27 protruding into the cylindrical portion. Therefore, when the crimping portion 22 is deformed into the cylindrical portion using a rivet tool (a pair of upper and lower dies 30, 40), the crimping portion 22 is crimped to the conductor core wire 11 in a shape in which the protrusion 27 of the cylindrical inner surface 25 of the crimping portion bites the conductor core wire 11 of the electric wire 10. In addition, the protrusion 27 of the cylindrical inner surface 25 of the crimping portion 22 is strongly pressed against the conductor core wire 11. Therefore, compared with the case where there is no protrusion on the cylindrical inner surface 25 of the crimping portion 22, the contact area and contact pressure between the crimping portion 22 and the conductor core wire 11 are increased. This improves the reliability of the electrical connection between the crimping portion 22 and the conductor core wire 11. Therefore, according to the manufacturing method and the terminal 20 of the present embodiment, it is possible to manufacture the terminal-attached electric wire 1 that can improve the reliability of the electrical connection between the terminal 20 and the electric wire 10. According to the terminal-attached electric wire 1 of the present embodiment, it is possible to improve the reliability of the electrical connection between the terminal 20 and the electric wire 10.

[0112] In addition, the rivet tool (a pair of upper and lower molds 30, 40) has protrusions 32, 42 on the rivet surfaces 31, 41 to recess the crimping portion 22 into the cylindrical portion of the crimping portion 22. As a result, when crimping, the crimping portion 22 is recessed into the cylindrical portion, so that the crimping portion 22 is crimped to the conductor core wire 11 in a shape in which the protrusion 27 of the cylindrical inner surface 25 bites deeper into the conductor core wire 11 of the electric wire 10, and the protrusion 27 of the cylindrical inner surface 25 is pressed against the conductor core wire 11 more strongly. Therefore, according to the manufacturing method of the present embodiment, the terminal-attached electric wire 1 that can further improve the reliability of the electrical connection between the terminal 20 and the electric wire 10 can be manufactured. According to the terminal-attached electric wire 1 of the present embodiment, the reliability of the electrical connection between the terminal 20 and the electric wire 10 can be improved.

[0113] <Other embodiments>

[0114] The present disclosure is not limited to the above-mentioned embodiments, and various modifications can be adopted within the scope of the present disclosure. For example, the present disclosure is not limited to the above-mentioned embodiments, and modifications, improvements, etc. can be made as appropriate. In addition, the materials, shapes, sizes, quantities, configuration positions, etc. of the components in the above-mentioned embodiments are arbitrarily selected and are not limited as long as the present disclosure can be implemented.

[0115] For example, in the first to eighth embodiments, the upper and lower pairs of dies 30, 40 used when riveting the crimping portion 22 of the terminal 20 are formed so that, when clamped, the entire riveting surface has a hexagonal cross-sectional shape (see Figure 4). Alternatively, the upper and lower pairs of dies 30, 40 may be configured so that, when clamped, the entire riveting surface has a cross-sectional shape other than a hexagon (e.g., a square, a semicircle, a crescent, etc.). In this case, the outer surface 24 of the crimping portion 22 after crimping has a cross-sectional shape other than a hexagon corresponding to the cross-sectional shape of the entire riveting surface of the dies 30, 40.

[0116] Furthermore, in the first to eighth embodiments, the protrusions 32 and 42 are respectively provided on the riveting surfaces 31 and 41 of the upper and lower pairs of dies 30 and 40 used when riveting the crimping portion 22 of the terminal 20. Alternatively, the riveting surface 31 of the die 30 may not be provided with the protrusion 32, and / or the riveting surface 41 of the die 40 may not be provided with the protrusion 42. In this case, the outer surface 24 of the crimping portion 22 after crimping does not form any one or both of the recesses 28 and 29.

[0117] Furthermore, in the first to eighth embodiments, the cylindrical inner surface 25 of the crimping portion 22 has a shape in which a plurality of circles are combined in a manner that partially overlaps with each other in cross section. Alternatively, the cylindrical inner surface 25 of the crimping portion 22 may have a shape in which a plurality of ellipses are combined in a manner that partially overlaps with each other, or a shape in which one or more circles and one or more ellipses are combined in a manner that partially overlaps with each other. If a plurality of circles or ellipses are combined in this manner, it is preferred that the cylindrical inner surface 25 has two or more protrusions 27 (i.e., the cylindrical inner surface 25 after crimping also has two or more protrusions 27).

[0118] Furthermore, in the fifth, seventh and eighth embodiments, the position of the protrusion 27 on the cylindrical inner surface 25 of the base end portion 22A and the position of the protrusion 27 on the cylindrical inner surface 25 of the distal end portion 22B coincide with each other in the circumferential direction (direction around the axis of the terminal 20). In the above-mentioned sixth embodiment, the position of the protrusion 27 on the cylindrical inner surface 25 of the base end portion 22A and the position of the protrusion 27 on the cylindrical inner surface 25 of the distal end portion 22B are offset by 180 degrees in the circumferential direction (direction around the axis of the terminal 20). Alternatively, the cylindrical inner surface 25 may be formed so that the position of the protrusion 27 on the cylindrical inner surface 25 of the base end portion 22A and the position of the protrusion 27 on the cylindrical inner surface 25 of the distal end portion 22B are offset by any angle in the circumferential direction (direction around the axis of the terminal 20). Such a cylindrical inner surface 25 can be formed by, for example, preparing the base end portion 22A and the distal end portion 22B as independent components, performing cutting in both the base end portion 22A and the distal end portion 22B to form the cylindrical inner surface 25, then positioning the base end portion 22A and the distal end portion 22B so that the position of the protrusion 27 is offset by an arbitrary angle, and joining the base end portion 22A and the distal end portion 22B.

[0119] Here, features of the embodiments of the method for manufacturing the electric wire with terminal 1 , the terminal, and the electric wire with terminal according to the above-described present disclosure are briefly summarized and listed in the first to fifteenth aspects, respectively.

[0120] According to a first aspect of the present disclosure, a method for manufacturing a terminal-equipped electric wire (1) is provided, wherein a terminal (20) is crimped to a conductor core wire (11) of the electric wire (10). The terminal (20) includes a connecting portion (21) configured to be connected to a mating terminal and a crimping portion (22) configured to be crimped to the conductor core wire (11). The crimping portion (22) has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal (20), the shape before crimping is that the cylindrical inner surface (25) of the crimping portion (22) has a shape of a protrusion (27) protruding into the cylindrical portion. The manufacturing method comprises: inserting the conductor core wire (11) into the cylindrical portion of the crimping portion (22); and crimping the crimping portion (22) to the conductor core wire (11) by riveting the crimping portion (22) using a riveting tool (30, 40), wherein the riveting tool (30, 40) is configured to deform the crimping portion (22) into the cylindrical portion by pressing a riveting surface (31, 41) against the crimping portion (22).

[0121] According to the manufacturing method of the electric wire with terminal having the structure of the above-mentioned first aspect, the crimping part of the terminal has a continuous cylindrical shape (so-called closed cylindrical shape) without interruption in the circumferential direction, and in the cross section orthogonal to the axis of the terminal, the shape before crimping is that the cylindrical inner surface of the crimping part has the shape of a protrusion protruding into the cylindrical part. Therefore, when the crimping part is deformed into the cylindrical part using a riveting tool, the crimping part is crimped to the conductor core wire in the shape of the protrusion of the cylindrical inner surface of the crimping part biting the conductor core wire. In addition, the protrusion of the cylindrical inner surface of the crimping part is strongly pressed against the conductor core wire. Therefore, compared with the case where there is no protrusion on the cylindrical inner surface of the crimping part, the contact area and contact pressure between the crimping part and the conductor core wire are increased. This increases the reliability of the electrical connection between the crimping part and the conductor core wire. Therefore, according to the manufacturing method of this structure, it is possible to manufacture an electric wire with terminal that can improve the reliability of the electrical connection between the terminal and the electric wire.

[0122] According to a second aspect of the present invention, in the manufacturing method according to the above-mentioned first aspect, the cylindrical inner surface (25) of the crimping portion (22) has the following shape in the cross section: a shape formed by combining a plurality of circles (26) while partially overlapping each other, a shape formed by combining a plurality of ellipses while partially overlapping each other, or a shape formed by combining one or more circles (26) and one or more ellipses while partially overlapping each other.

[0123] According to the manufacturing method of the electric wire with a terminal having the configuration of the second aspect described above, the cylindrical inner surface of the crimping portion has a shape in which a plurality of circular and / or elliptical shapes are combined while partially overlapping each other. As a result, the overlapping positions of the circular and / or elliptical shapes form a protrusion in which the cylindrical inner surface protrudes into the cylindrical portion. In addition, by forming the cylindrical inner surface of the crimping portion into a combination of circles, for example, when manufacturing the terminal by cutting, a hole in the crimping portion can be easily formed by a drill or the like.

[0124] According to a third aspect of the present disclosure, in the manufacturing method according to the first aspect, the crimping portion (22) includes a first portion (22A) and a second portion (22B) arranged in the axial direction. The first portion (22A) has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as it approaches the second portion (22B). The second portion (22B) has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as it approaches the first portion (22A).

[0125] According to the fourth aspect of the present disclosure, in the manufacturing method according to the above-mentioned third aspect, the cylindrical internal space of the first part (22A) and the cylindrical internal space of the second part (22B) are adjacent to and connected to each other, or, the cylindrical internal space of the first part (22A) and the second part (22B) are connected to each other via another cylindrical internal space.

[0126] According to the manufacturing method of the terminal-attached electric wire having the configuration of the third and fourth aspects described above, the cylindrical inner space of the first part of the crimping part gradually becomes smaller as it approaches the second part, and the cylindrical inner space of the second part of the crimping part gradually decreases as it approaches the first part. Therefore, if the cylindrical inner space of the first part and the cylindrical inner space of the second part are adjacent to each other and communicated, there is a position where the cylindrical inner space is locally narrowed at the boundary between the first part and the second part. At this position, the cylindrical inner surface has a shape protruding into the cylindrical part, as in the above-mentioned protrusion. On the other hand, if the cylindrical inner space of the first part and the cylindrical inner space of the second part are communicated with each other via another cylindrical inner space, there is a position where the cylindrical inner space is locally narrowed at the boundary between the first part and the part defining the other cylindrical inner space, and at the boundary between the second part and the part defining the other cylindrical inner space. Therefore, when crimping, the cylindrical inner surface of this position is strongly pressed against the conductor core wire, as in the above-mentioned protrusion. In addition, the cylindrical inner surface of the first part and the cylindrical inner surface of the second part are inclined relative to the conductor core wire of the electric wire, thereby increasing the contact area between the cylindrical inner surface and the conductor core wire. This further improves the reliability of the electrical connection between the crimping portion and the conductor core wire.

[0127] According to the fifth aspect of the present disclosure, in the manufacturing method according to the third aspect above, the position of the protrusion (27) in the cylindrical inner surface (25) of the first part (22A) and the position of the protrusion (27) in the cylindrical inner surface (25) of the second part (22B) are different in the direction around the axis.

[0128] According to the manufacturing method of the electric wire with a terminal having the configuration of the fifth aspect described above, at the time of crimping, the protruding portion of the first part and the protruding portion of the second part bite the conductor core wire from different positions in the direction around the axis. This uniformly increases the contact area and contact pressure between the crimping portion and the conductor core wire in the direction around the axis, thereby further improving the reliability of the electrical connection between the crimping portion and the conductor core wire.

[0129] According to a sixth aspect of the present invention, in a manufacturing method according to any one of the first to fifth aspects, the riveting tool (30, 40) has a protrusion (32, 42) on the riveting surface (31, 41) to recess the crimping portion (22) into the cylindrical portion of the crimping portion (22).

[0130] According to the manufacturing method of the electric wire with terminal having the structure of the sixth aspect described above, the riveting tool has a protrusion on the riveting surface to recess the crimping part into the cylindrical part of the crimping part. Therefore, during crimping, the crimping part is recessed into the cylindrical part, so that the crimping part is crimped to the conductor core wire in a shape in which the protrusion of the cylindrical inner surface bites more deeply into the conductor core wire of the electric wire, and the protrusion of the cylindrical inner surface presses more strongly against the conductor core wire. Therefore, according to the manufacturing method of this structure, it is possible to manufacture an electric wire with terminal that can further improve the reliability of the electrical connection between the terminal and the electric wire.

[0131] According to a seventh aspect of the present invention, a terminal (20) configured to be crimped to a conductor core wire (11) of an electric wire (10) comprises: a connecting portion (21) configured to be connected to a mating terminal; and a crimping portion (22) configured to be crimped to the conductor core wire (11). The crimping portion (22) has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal (20), the shape before crimping is that the cylindrical inner surface (25) of the crimping portion has a shape of a protrusion (27) protruding into the cylindrical portion.

[0132] According to the terminal having the structure of the seventh aspect described above, the crimping portion of the terminal has a continuous cylindrical shape (so-called closed cylindrical shape) that is uninterrupted in the circumferential direction, and in the cross section orthogonal to the axis of the terminal, the shape before crimping is that the cylindrical inner surface of the crimping portion has a shape of a protrusion protruding into the cylindrical portion. Therefore, when the crimping portion is deformed into the cylindrical portion using a riveting tool, the crimping portion is crimped to the conductor core wire in the shape of the protrusion of the cylindrical inner surface of the crimping portion biting the conductor core wire. In addition, the protrusion of the cylindrical inner surface of the crimping portion is strongly pressed onto the conductor core wire. Therefore, compared with the case where there is no protrusion on the cylindrical inner surface of the crimping portion, the contact area and contact pressure between the crimping portion and the conductor core wire are increased. This increases the reliability of the electrical connection between the crimping portion and the conductor core wire. Therefore, according to the terminal of this structure, it is possible to manufacture a terminal electric wire that can improve the reliability of the electrical connection between the terminal and the electric wire.

[0133] According to the eighth aspect of the present disclosure, in the terminal (20) according to the seventh aspect above, the cylindrical inner surface (25) of the crimping portion (22) has in the cross section: a shape formed by combining a plurality of circles (26) while partially overlapping each other, a shape formed by combining a plurality of ellipses while partially overlapping each other, or a shape formed by combining one or more circles (26) and one or more ellipses while partially overlapping each other.

[0134] According to the terminal having the structure of the eighth aspect, the cylindrical inner surface of the crimping portion has a shape in which a plurality of circular and / or elliptical shapes are combined while partially overlapping each other. As a result, the overlapping positions of the circular and / or elliptical shapes form a protrusion protruding from the cylindrical inner surface into the cylindrical portion. In addition, by forming the cylindrical inner surface of the crimping portion into a circular combination, for example, when manufacturing the terminal by cutting, a hole in the crimping portion can be easily formed by a drill bit or the like.

[0135] According to a ninth aspect of the present disclosure, in the terminal (20) according to the seventh aspect, the crimping portion (22) includes a first portion (22A) and a second portion (22B) arranged in the axial direction. The first portion (22A) has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as it approaches the second portion (22B). The second portion (22B) has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as it approaches the first portion (22A).

[0136] According to the tenth aspect of the present invention, in the terminal (20) according to the above-mentioned ninth aspect, the cylindrical internal space of the first part (22A) and the cylindrical internal space of the second part (22B) are adjacent to and connected to each other, or, the cylindrical internal space of the first part (22A) and the cylindrical internal space of the second part (22B) are connected to each other via another cylindrical internal space.

[0137] According to the terminal having the structure of the ninth and tenth aspects, the cylindrical inner space of the first part of the crimping part gradually becomes smaller as it approaches the second part, and the cylindrical inner space of the second part of the crimping part gradually decreases as it approaches the first part. Therefore, if the cylindrical inner space of the first part and the cylindrical inner space of the second part are adjacent to each other and communicated, there is a position where the cylindrical inner space is locally narrowed at the boundary between the first part and the second part. At this position, the cylindrical inner surface has a shape protruding into the cylindrical part, as in the above-mentioned protrusion. On the other hand, if the cylindrical inner space of the first part and the cylindrical inner space of the second part are communicated with each other via another cylindrical inner space, there is a position where the cylindrical inner space is locally narrowed at the boundary between the first part and the part defining the other cylindrical inner space, and at the boundary between the second part and the part defining the other cylindrical inner space. Therefore, when crimping, the cylindrical inner surface of this position is strongly pressed against the conductor core wire, as in the above-mentioned protrusion. In addition, the cylindrical inner surface of the first part and the cylindrical inner surface of the second part are inclined relative to the conductor core wire of the electric wire, thereby increasing the contact area between the cylindrical inner surface and the conductor core wire. This further improves the reliability of the electrical connection between the crimping portion and the conductor core wire.

[0138] According to the eleventh aspect of the present invention, in the terminal (20) according to the above-mentioned ninth aspect, the position of the protrusion (27) on the cylindrical inner surface (25) of the first part (22A) and the position of the protrusion (27) on the cylindrical inner surface (25) of the second part (22B) are different in the direction around the axis.

[0139] According to the terminal having the structure of the eleventh aspect, when crimping, the protrusion of the first part and the protrusion of the second part bite the conductor core wire from different positions in the direction around the axis. This uniformly increases the contact area and contact pressure between the crimping part and the conductor core wire in the direction around the axis, thereby further improving the reliability of the electrical connection between the crimping part and the conductor core wire.

[0140] According to a twelfth aspect of the present invention, a terminal-equipped electric wire (1) comprises: an electric wire (10); and a terminal (20) crimped to a conductor core wire (11) of the electric wire (10). The terminal (20) comprises: a connecting portion (21) configured to be connected to a mating terminal; and a crimping portion (22) crimped to the conductor core wire (11). The crimping portion (22) has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal (20), the cylindrical inner surface (25) of the crimping portion has a shape of multiple curved surfaces protruding from the cylindrical portion. In the cross section, the position where one of the curved surfaces is connected to another of the curved surfaces defines a protrusion (27) protruding into the cylindrical portion of the crimping portion (22).

[0141] According to the electric wire with terminals having the structure of the above-mentioned twelfth aspect, the crimping portion of the terminal has a continuous cylindrical shape without interruption in the circumferential direction (so-called closed cylindrical shape), and in the cross section orthogonal to the axis of the terminal, the shape before crimping is that the cylindrical inner surface of the crimping portion has a shape of a protrusion protruding into the cylindrical portion. As a result, the crimping portion is crimped to the conductor core wire in the shape of the protrusion of the cylindrical inner surface of the crimping portion biting the conductor core wire. In addition, the protrusion of the cylindrical inner surface of the crimping portion is strongly pressed onto the conductor core wire. Therefore, compared with the case where there is no protrusion on the cylindrical inner surface of the crimping portion, the contact area and contact pressure between the crimping portion and the conductor core wire are increased. This increases the reliability of the electrical connection between the crimping portion and the conductor core wire. Therefore, according to the electric wire with terminals of this structure, the reliability of the electrical connection between the terminal and the wire can be improved.

[0142] According to the thirteenth aspect of the present invention, in the terminal-equipped electric wire (1) according to the above-mentioned twelfth aspect, the cylindrical inner surface (25) of the crimping portion (22) has two or more protrusions (27) on the cylindrical inner surface (25) of the crimping portion (22) in the cross section.

[0143] According to the electric wire with terminal having the configuration of the above thirteenth aspect, the cylindrical inner surface is provided with two or more protrusions, thereby further enhancing the effect of improving the reliability of the electrical connection by the above protrusions.

[0144] According to a fourteenth aspect of the present invention, in the terminal-attached electric wire (1) according to the twelfth aspect, the crimping portion (22) includes a first portion (22A) and a second portion (22B) arranged in the axial direction. The position of the protrusion (27) on the cylindrical inner surface (25) of the first portion (22A) and the position of the protrusion (27) on the cylindrical inner surface (25) of the second portion (22B) are different in the direction around the axis.

[0145] According to the terminal-attached electric wire having the configuration of the above-mentioned fourteenth aspect, the protrusion of the first part and the protrusion of the second part bite the conductor core wire from different positions in the direction around the axis. This uniformly increases the contact area and contact pressure between the crimping part and the conductor core wire in the direction around the axis, thereby further improving the reliability of the electrical connection between the crimping part and the conductor core wire.

[0146] According to a fifteenth aspect of the present invention, in the terminal-equipped electric wire (1) according to any one of the above-mentioned twelfth to fourteenth aspects, the crimping portion (22) includes a recess (28) formed by recessing the cylindrical outer surface of the crimping portion (22) into the cylindrical portion.

[0147] According to the electric wire with terminal having the structure of the fifteenth aspect, the crimping portion is recessed in the cylindrical portion, so that the crimping portion is crimped to the conductor core wire of the electric wire in a shape in which the protrusion of the inner surface of the cylindrical portion bites more deeply, and the protrusion of the inner surface of the cylindrical portion presses more strongly against the conductor core wire. Therefore, according to the electric wire with terminal of this structure, the reliability of the electrical connection between the terminal and the electric wire can be further improved.

Claims

1. A method for manufacturing a terminal-equipped electric wire, wherein: The terminal is crimped to the conductor core of the wire, where The terminal includes a connecting portion to be connected to a mating terminal and a crimping portion to be crimped to the conductor core wire. The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the shape before crimping is a shape in which the cylindrical inner surface of the crimping portion has a protrusion protruding into the cylindrical portion, and The manufacturing method comprises: inserting the conductor core wire into the cylindrical portion of the crimping portion; and The crimping portion is crimped to the conductor core wire by riveting the crimping portion using a riveting tool configured to deform the crimping portion into the cylindrical portion by pressing a caulking surface against the crimping portion.

2. The manufacturing method according to claim 1, wherein: The cylindrical inner surface of the crimping portion has, in the cross section: A shape formed by combining multiple circles while partially overlapping each other. A shape formed by combining multiple ellipses while partially overlapping each other, or A shape formed by combining one or more circles and one or more ellipses while partially overlapping each other.

3. The manufacturing method according to claim 1, wherein: The crimping portion includes a first portion and a second portion arranged in the axial direction, The first portion has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as approaching the second portion, and The second portion has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as approaching the first portion.

4. The manufacturing method according to claim 3, wherein: The cylindrical internal space of the first portion and the cylindrical internal space of the second portion are adjacent to and communicate with each other, or the cylindrical internal space of the first portion and the cylindrical internal space of the second portion are communicated with each other via another cylindrical internal space.

5. The manufacturing method according to claim 3, wherein: The position of the protrusion in the cylindrical inner surface of the first portion and the position of the protrusion in the cylindrical inner surface of the second portion are different in a direction around the axis.

6. The manufacturing method according to any one of claims 1 to 5, wherein: The caulking tool has a protrusion on the caulking surface to recess the crimping portion into the cylindrical portion of the crimping portion.

7. A terminal crimped to a conductor core wire of an electric wire, the terminal comprising: The connecting part to be connected to the mating terminal; as well as A crimping portion to be crimped to the conductor core wire, wherein The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section perpendicular to the axis of the terminal, the shape before crimping is a shape in which the cylindrical inner surface of the crimping portion has a protrusion protruding into the cylindrical portion.

8. The terminal according to claim 7, wherein: The cylindrical inner surface of the crimping portion has, in the cross section: A shape formed by combining multiple circles while partially overlapping each other. A shape formed by combining multiple ellipses while partially overlapping each other, or A shape formed by combining one or more circles and one or more ellipses while partially overlapping each other.

9. The terminal according to claim 7, wherein: The crimping portion includes a first portion and a second portion arranged in the axial direction, The first portion has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as approaching the second portion, and The second portion has a shape in which the cross-sectional area of ​​the cross section of the cylindrical internal space decreases as approaching the first portion.

10. The terminal according to claim 9, wherein The cylindrical internal space of the first portion and the cylindrical internal space of the second portion are adjacent to and communicate with each other, or the cylindrical internal space of the first portion and the cylindrical internal space of the second portion are communicated with each other via another cylindrical internal space.

11. The terminal according to claim 9, wherein The position of the protrusion in the cylindrical inner surface of the first portion and the position of the protrusion in the cylindrical inner surface of the second portion are different in a direction around the axis.

12. An electric wire with a terminal, comprising: electric wire; as well as a terminal crimped to the conductor core of the electric wire, wherein The terminal comprises: The connecting part to be connected to the mating terminal; as well as To be crimped to the crimping portion of the conductor core wire, The crimping portion has a continuous cylindrical shape without interruption in the circumferential direction, and in a cross section orthogonal to the axis of the terminal, the cylindrical inner surface of the crimping portion has a shape of a plurality of curved surfaces protruding from the cylindrical portion, and In the cross section, a position where one of the curved surfaces and the other curved surface are connected defines a protrusion that protrudes into the cylindrical portion of the crimping portion.

13. The electric wire with a terminal according to claim 12, wherein: In the cross section, the cylindrical inner surface of the crimping portion has two or more protrusions on the cylindrical inner surface of the crimping portion.

14. The electric wire with a terminal according to claim 12, wherein The crimping portion includes a first portion and a second portion arranged in the axial direction, and The position of the protrusion in the cylindrical inner surface of the first portion and the position of the protrusion in the cylindrical inner surface of the second portion are different in a direction around the axis.

15. The electric wire with terminal according to any one of claims 12 to 14, wherein The crimping portion includes a recessed portion formed by recessing a cylindrical outer surface of the crimping portion into the cylindrical portion.

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