Method for manufacturing electric wire equipped with terminal

Abstract

A manufacturing method for an electric wire equipped with terminals, including a step of press-fitting a first terminal to one end of an electric wire, a step of press-fitting a second terminal to the other end of the electric wire with a tubular sealing member, a first waterproofing step of providing an anticorrosion member covering an element wire harness of the electric wire at the one end of the electric wire, and a second waterproofing step of providing a sealing member to fill gaps between conductive element wires of the element wire harness in a tubular insulating sheath at the other end of the electric wire. The second waterproofing step includes a step of applying a moisture-curing resin to the element wire harness, and a step of applying a curing accelerator that promotes curing of the moisture-curing resin to the element wire harness.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing an electric wire equipped with terminals, wherein the terminals are crimped to both ends of the electric wire. Background Art

[0002] In the prior art, there have been proposed electric wires equipped with terminals for use in communication, power supply, etc. between devices mounted on vehicles, etc. In general, such electric wires equipped with terminals have a structure in which terminals are crimped to both ends of the electric wire, and are used to accommodate the two terminals in corresponding terminal accommodating chambers of a connector housing. In addition, each connector is connected to a mating connector of a corresponding device, etc. In addition, for example, in one of the electric wires equipped with terminals in the prior art, the component wiring harness exposed from the end of the electric wire is covered with an anti-corrosion member to prevent corrosion of the crimped portion between the electric wire and the terminal, etc. (for example, see JP2019-129067A).

[0003] On the one hand, in electric wires equipped with terminals that are wired in places that may be exposed to water, such as the engine room of a vehicle, generally, a sealing member (such as a rubber plug) is crimped to the end of the electric wire together with the terminal, and the gap between the terminal accommodating chamber of the connector housing and the electric wire is sealed by the sealing member. Connectors with such a waterproof structure are also called waterproof connectors because water can be prevented from entering the terminal accommodating chamber from the outside of the connector. On the other hand, generally, sealing members are not provided in electric wires equipped with terminals that are wired in places where the possibility of exposure to water is relatively low, such as the interior of a vehicle. Such connectors are also called non-waterproof connectors.

[0004] The waterproof connector is assembled to a mating connector in an electrical junction box, for example, located in the engine compartment of a vehicle. In this context, if the sealing performance of the electrical junction box itself is improved from the perspective of waterproofing, the air pressure in the electrical junction box may become lower than the air pressure inside the vehicle (i.e., negative pressure may be generated) because the air temperature in the electrical junction box drops sharply when, for example, the engine being driven is stopped. In this case, water, such as moisture, may be drawn from the ends of the wires on the non-waterproof connector side wired inside the vehicle toward the ends of the wires on the waterproof connector side wired in the engine compartment through the tiny gaps between the conductive element lines in the wires. In this water absorption phenomenon, since the water passes through the wires and reaches the terminals on the waterproof connector side, it is difficult to block the water with the above-mentioned sealing member. Summary of the Invention

[0005] An object of the present disclosure is to provide a method for manufacturing a terminal-equipped electric wire capable of preventing water from entering gaps between conductive element lines of the electric wire.

[0006] In order to achieve the above-mentioned object, a method for manufacturing a terminal-equipped electric wire according to the present disclosure is characterized as follows.

[0007] Aspects of non-limiting embodiments of the present disclosure relate to a method for manufacturing a terminal-equipped electric wire, the terminal-equipped electric wire comprising an electric wire, a first terminal, and a second terminal, the electric wire having an element wire harness formed by bundling a plurality of conductive element wires and a tubular insulating sheath covering the element wire harness, the first terminal being crimped to one end of the electric wire, and the second terminal being crimped to the other end of the electric wire, the method comprising:

[0008] a step of crimping a first terminal to one end of the electric wire to electrically connect the component wire bundle exposed from the one end of the electric wire and the first terminal;

[0009] a step of crimping a second terminal to the other end of the electric wire so that the component wire crimping portion of the second terminal is crimped to the component wire bundle exposed from the other end of the electric wire, and crimping the sheath crimping portion of the second terminal to the tubular sealing member attached to the outer periphery of the other end of the electric wire;

[0010] a first waterproofing step of providing an anti-corrosion member at one end of the electric wire to which the first terminal is crimped, the anti-corrosion member covering the component harness to isolate the component harness from outside air; and

[0011] A second waterproofing step is to provide a sealing member at the other end of the electric wire to which the second terminal is crimped to fill the gaps between the conductive element wires in the tubular insulating sheath and seal the interior of the tubular insulating sheath, wherein

[0012] The second waterproofing step includes

[0013] a step of applying a moisture-curable resin to the component wire bundle exposed to the outside and located between the component wire crimping portion and the sheath crimping portion, and

[0014] A step of applying a curing accelerator that promotes curing of the moisture-curable resin to the component wire bundle exposed to the outside and located between the component wire crimping portion and the sheath crimping portion.

[0015] According to the manufacturing method for an electric wire equipped with a terminal disclosed in the present invention, after the terminals (i.e., the first terminal and the second terminal) are crimped to both ends of the electric wire, in a first waterproofing step, at one end of the electric wire to which a non-waterproof first terminal that does not include a sealing member is crimped, an anti-corrosion member is provided to cover the element wire bundle exposed from the insulating sheath to isolate the element wire bundle from the outside air. On the other hand, in a second waterproofing step, at the other end of the electric wire to which a waterproof second terminal that includes a sealing member is crimped, a sealing member is provided to fill the gap between the conductive element wires in the tubular insulating sheath and seal the inside of the tubular insulating sheath. In this article, the second waterproofing step can be carried out quickly by using a moisture-curing resin and a curing accelerator in combination. In addition, since the gap between the conductive element wires is sealed at the other end of the electric wire (i.e., the end of the electric wire to which the waterproof second terminal is attached), water ingress due to the above-mentioned negative pressure can be prevented even when the other end of the electric wire is wired in a place where temperature fluctuations are large (such as an engine room, etc.). Even if the other end of the wire is not completely sealed, the corrosion-resistant member covers one end of the wire, so the amount of water absorbed when negative pressure is generated is limited to the very small amount of water initially present in the tubular insulating sheath of the wire. Therefore, according to the manufacturing method of this configuration, it is possible to manufacture a terminal-equipped wire that can prevent water from entering the gaps between the conductive elements of the wire.

[0016] The present disclosure has been briefly described above. The details of the present disclosure will be further clarified by reading the following embodiments for implementing the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a side view of the terminal-equipped electric wire according to the embodiment of the present disclosure, illustrating a state before a corrosion-resistant member and a sealing member are provided in the terminal-equipped electric wire.

[0018] Figure 2 Is crimped to Figure 1 FIG. 1 is a top view of a non-waterproof first terminal at one end of a terminal-equipped electric wire shown in FIG.

[0019] Figure 3 Is crimped to Figure 1 FIG. 1 is a top view of a waterproof second terminal at the other end of the terminal-equipped electric wire shown in FIG.

[0020] Figure 4 It is along Figure 2 AA in FIG. , and showing a step of providing an anti-corrosion member at one end of the electric wire, Figure 2 The first terminal shown is crimped to one end of a wire.

[0021] Figure 5 It is along Figure 3is a cross-sectional view taken along line B-B in Figure 3 is a first stage of a step of crimping the other end of the electric wire to which the second terminal shown in

[0022] Figure 6 is a cross-sectional view taken along line B-B in Figure 3 is a second stage of a step of crimping the other end of the electric wire to which the second terminal shown in Figure 3

[0023] Figure 7 is a cross-sectional view taken along line B-B in Figure 3 is a third stage of a step of crimping the other end of the electric wire to which the second terminal shown in Figure 3

[0024] Figure 8 is a cross-sectional view taken along line B-B in Figure 3 is a fourth stage of a step of crimping the other end of the electric wire to which the second terminal shown in Figure 3

[0025] Figure 9 is an enlarged view of a portion C in Figure 8

[0026] Figure 10 is a cross-sectional view taken along line D-D in Figure 9

[0027] Figure 11 is a conceptual view showing an example of a state in which an electric wire equipped with a terminal according to an embodiment of the disclosure is installed on a vehicle and used. DETAILED DESCRIPTION

[0028] <EMBODIMENT>

[0029] Hereinafter, an electric wire 1 equipped with a terminal according to an embodiment of the disclosure will be described with reference to the accompanying drawings. As shown in Figure 1 and Figure 11 , the electric wire 1 equipped with a terminal includes an electric wire 10, a first terminal 20 crimped to one end of the electric wire 10, and a second terminal 30 crimped to the other end of the electric wire 10. As shown in Figure 11 , a waterproof sealing member 40 is attached to the outer periphery of the other end of the electric wire to which the second terminal 30 is crimped, and the sealing member is not provided at the one end of the electric wire 10 to which the first terminal 20 is crimped. An anticorrosion member 50 is provided at the one end of the electric wire 10 to which the first terminal 20 is crimped, and a sealing member 60 is provided at the other end of the electric wire 10 to which the second terminal 30 is crimped. ​​​​​

[0030] As Figure 11 shown in FIG. 1, the non-waterproof first terminal 20, which does not include a waterproof sealing member, is attached to the connector housing 70. Specifically, the connector housing 70 includes a receiving hole (not shown) for inserting and accommodating the first terminal 20 crimped to one end of the electric wire 10, and a terminal accommodating chamber (not shown) communicating with the receiving hole. The first terminal 20 is inserted into the receiving hole of the connector housing 70 and accommodated in the terminal accommodating chamber. The connector including the connector housing 70, the first terminal 20, and the like is generally fitted to a counterpart connector provided in an apparatus (not shown) arranged in a vehicle interior, which has a relatively low possibility of exposure to water.

[0031] On the other hand, the waterproof second terminal 30 having the waterproof sealing member 40 is attached to the connector housing 80. Specifically, the connector housing 80 includes a receiving hole (not shown) for receiving and accommodating the second terminal 30 crimped to the other end of the electric wire 10, and a terminal accommodating chamber (not shown) communicating with the receiving hole. The second terminal 30 is inserted into the receiving hole of the connector housing 80 and accommodated in the terminal accommodating chamber. When the second terminal 30 is accommodated in the terminal accommodating chamber, the inner wall surface of the receiving hole and the sealing member 40 are in close contact with each other, thereby preventing water from entering the terminal accommodating chamber from the receiving hole (the post-fitting side). The connector including the connector housing 80, the second terminal 30, and the like is generally fitted to a counterpart connector provided in an electrical junction block (not shown) disposed in an engine room 90 of a vehicle which is likely to be exposed to water. The gap between the connector housing 80 and the housing (not shown) of the counterpart connector to be fitted is sealed with a gasket or the like, and also prevents water from entering the terminal accommodating chamber from the fitting counterpart (the pre-fitting side).

[0032] In a state where the second terminal 30 is accommodated in the terminal accommodating chamber of the connector housing 80, the sealing member 40 seals the gap between the terminal accommodating chamber and the electric wire 10, whereby it is possible to prevent water from entering the inside of the terminal accommodating chamber from the outside. That is, the second terminal 30, the sealing member 40, and the connector housing 80 constitute a connector having a waterproof structure, and this connector is also referred to as a waterproof connector. On the other hand, the first terminal 20 and the connector housing 70 constitute a connector not having a waterproof structure, and this connector is also referred to as a non-waterproof connector. The electric wire 1 equipped with the terminals, the connector housing 70, and the connector housing 80 constitute a wiring 2 (see FIG. 2) laid in a vehicle. Figure 11

[0033] Hereinafter, the electric wire 10, the first terminal 20, the second terminal 30, and the sealing member 40 constituting the electric wire 1 equipped with the terminals will be described in order. First, the electric wire 10 will be described. As shown in FIG. 1, the electric wire 10 includes a plurality of electrically conductive element wires 11a (see FIG. 2) and an insulating layer 12 covering the plurality of electrically conductive element wires 11a. Figure 1 Figure 9 Figure 10 The plurality of electrically conductive element wires 11a are arranged in parallel to each other in the longitudinal direction of the electric wire 10. The plurality of electrically conductive element wires 11a are covered with the insulating layer 12. The plurality of electrically conductive element wires 11a are electrically connected to each other at the first terminal 20 and the second terminal 30.​​​ Figure 10 ) bundled with the element wires 11 and a tubular insulating sheath 12 covering the element wires 11. The conductive element wires 11a are made of a metal material such as aluminum. Each of the two ends of the electric wire 10 is subjected to a process of removing a portion of the insulating sheath 12 to expose the end of the element wire 11. Hereinafter, for the sake of convenience of explanation, in the extending direction of the electric wire 10, the side from the center of the electric wire 10 toward the end of the electric wire 10 will be referred to as the "distal side", and the side from the end of the electric wire 10 toward the center of the electric wire 10 will be referred to as the "proximal side".

[0034] Next, the first terminal 20 will be described. The first terminal 20 is formed by pressing, bending, etc. a metal plate made of copper or a copper alloy. Figure 1 、 Figure 2 and Figure 4 As shown, the first terminal (female terminal) 20 includes a connecting portion 21, an element wire crimping portion 22 located on the proximal side of the connecting portion 21 and spaced apart from the connecting portion 21, and a sheath crimping portion 23 located on the proximal side of the element wire crimping portion 22 and spaced apart from the element wire crimping portion 22.

[0035] The connecting portion 21 has a rectangular box shape and has the function of inserting and connecting a mating terminal (male terminal). The component wire crimping portion 22 includes a pair of crimping blades 22a extending upward from both sides of the bottom and has the function of crimping the component wire 11 exposed on one end side of the electric wire 10. The sheath crimping portion 23 includes a pair of crimping blades 23a extending upward from both sides of its bottom and has the function of crimping the end portion on one end side of the insulating sheath 12 of the electric wire 10.

[0036] Next, the second terminal 30 will be described. The second terminal 30 is formed by pressing, bending, etc. a metal plate made of copper or a copper alloy. Figure 1 、 Figure 3 and Figure 5 As shown, the second terminal (female terminal) 30 includes a connecting portion 31, an element wire crimping portion 32 located on the proximal side of the connecting portion 31 and spaced apart from the connecting portion 31, and a sheath crimping portion 33 located on the proximal side of the element wire crimping portion 32 and spaced apart from the element wire crimping portion 32.

[0037] The connecting portion 31 has a rectangular box shape, and has a function of inserting and connecting a counterpart terminal (female terminal). The element wire crimping portion 32 includes a pair of crimping pieces 32a extending upward from both sides of the bottom portion, and has a function of crimping the element wire harness 11 exposed on the other end side of the electric wire 10. The sheath crimping portion 33 has a pair of crimping pieces 33a extending upward from both sides of the bottom portion, and has a function of crimping the end portion (more specifically, the small diameter portion 42 of the sealing member 40 arranged on the outer periphery of the end portion, which will be described later) on the other end side of the insulating sheath 12 of the electric wire 10.

[0038] Next, the sealing member 40 will be described. The sealing member 40 made of rubber includes a cylindrical large diameter portion 41 including a lip portion provided on the outer periphery thereof, and a cylindrical small diameter portion 42 having a diameter smaller than that of the large diameter portion 41. The sealing member 40 is attached to the other end of the electric wire 10 in a state where the small diameter portion 42 is located on the distal side of the large diameter portion 41, so that the small diameter portion 42 is located on the outer periphery of the end portion on the other end side of the insulating sheath 12 of the electric wire 10. The components constituting the electric wire 1 equipped with a terminal have been described in order above.

[0039] Next, a manufacturing method for the electric wire 1 equipped with a terminal will be described. In order to manufacture the electric wire 1 equipped with a terminal, first, as shown in Figure 1 , the first terminal 20 is crimped to one end of the electric wire 10 in a state where the sealing member 40 is provided on the electric wire 10, and the second terminal 30 is crimped to the other end of the electric wire 10. The order of crimping of the first terminal 20 and the second terminal 30 is not limited.

[0040] As shown in Figure 2 and Figure 4 , the end portion on the one end side of the electric wire 10 is placed on the sheath crimping portion 23 in a state where the element wire harness 11 exposed on the one end side of the electric wire 10 is placed on the element wire crimping portion 22, and the first terminal 20 is crimped to one end of the electric wire 10 by crimping the pair of crimping pieces 22a and the pair of crimping pieces 23a using a predetermined jig. In a state where the first terminal 20 is crimped, the distal portion of the element wire harness 11 protruding toward the distal side from the element wire crimping portion 22, and the element wire harness 11 located between the element wire crimping portion 22 and the sheath crimping portion 23 are exposed to the outside (contact with the outside air) (see Figure 2 ). The element wire crimping portion 22 after crimping has a B-crimp shape. That is, the element wire crimping portion 22 is crimped so that the pair of crimping pieces 22a bites into the element wire harness 11 to push away a part of the element wire harness 11. Therefore, as shown in Figure 4As shown in FIG, the component harness 11 is pushed open by a small gap 11b on the far side and near side of the crimping piece 22a. However, Figure 4 This is just a conceptual diagram showing the state where the anti-corrosion member 50 is provided in the first terminal 20. Such a gap 11b does not necessarily need to exist, and the gap 11b does not substantially affect the waterproof effect of the anti-corrosion member 50. The same applies to Figure 5 and 6 The gap 11b is shown in FIG.

[0041] like Figure 3 and Figure 5 , in a state where the component wire harness 11 exposed on the other end side of the electric wire 10 is placed on the component wire crimping portion 32, and the small diameter portion 42 of the sealing member 40 located at the end portion on the other end side of the insulating sheath 12 of the electric wire 10 is placed on the sheath crimping portion 33, the second terminal 30 is crimped to the other end of the electric wire 10 by crimping a pair of crimping pieces 32a and a pair of crimping pieces 33a using a predetermined jig. In a state where the second terminal 30 is crimped, the component wire harness 11 located between the component wire crimping portion 32 and the sheath crimping portion 33 is exposed to the outside (in contact with the outside air) (see Figure 3 ).

[0042] Next, if Figure 4 As shown in FIG, an anti-corrosion member 50 is provided at one end of the electric wire 10 to which the first terminal 20 is crimped (a first waterproofing step). The anti-corrosion member 50 is provided at one end of the electric wire 10 by applying a fluid ultraviolet curing resin to the surface of the component wiring harness 11 exposed to the outside at one end side of the electric wire 10 using a nozzle 100, and then irradiating the applied resin with ultraviolet rays to cure the resin. By providing the anti-corrosion member 50 in this manner, the entire surface of the distal end portion of the component wiring harness 11 exposed to the outside and the entire surface of the component wiring harness 11 located between the component wire crimping portion 22 and the sheath crimping portion 23 are covered by the anti-corrosion member 50 and isolated from the outside air (see FIG. Figure 4 ).

[0043] The viscosity of the fluid UV-curable resin at room temperature before curing is preferably 20 mPa·s or more, and more preferably 20 mPa·s or more and 100 mPa·s or less. Thus, by using a UV-curable resin having a suitably high viscosity, it is easy to construct the corrosion-resistant member 50 that appropriately covers the periphery of the component harness 11 exposed from the insulating sheath 12 while preventing liquid dripping, excessive penetration, and the like. Acrylic resin or epoxy resin can be used as the UV-curable resin.

[0044] The viscosity value as described above can be measured, for example, according to the viscosity test method specified in JIS Standard K 7233. Room temperature is a test temperature determined in this type of viscosity test method, and is, for example, 25°C.

[0045] As described above, after the corrosion-resistant member 50 is provided at one end of the electric wire 10 to which the first terminal 20 is crimped, the sealing member 60 is provided at the other end of the electric wire 10 to which the second terminal 30 is crimped. Figure 5 (Second waterproof step) as shown in FIG. Figure 5 and Figure 6 As shown, by first providing the first portion 60A as a part of the sealing member 60, the sealing member 60 is provided at the other end of the electric wire 10, and then, as shown in FIG. Figure 7 and Figure 8 As shown in FIG, a second portion 60B is provided as the remaining portion of the sealing member 60.

[0046] The first portion 60A of the sealing member 60 applies a fluid moisture-curing resin to the element wire harness 11 between the element wire crimping portion 32 and the sheath crimping portion 33 on the other end side of the electric wire 10, which is exposed to the outside, by using the nozzle 110, and allows the moisture-curing resin to penetrate into the gaps between the conductive element wires 11a (such as the gaps between the conductive element wires 11a). Figure 5 ), and then using the nozzle 120, a curing accelerator that promotes the curing of the resin is applied to the component wire harness 11 that is exposed to the outside and located between the component wire crimping portion 32 and the sheath crimping portion 33 on the other end side of the electric wire 10, and promotes the curing of the resin (as shown). Figure 6 ), and is provided at the other end of the electric wire 10.

[0047] By providing the first portion 60A of the sealing member 60 in this manner, in this example, Figure 5 、 Figure 6 、 Figure 9 and Figure 10As shown, except for the approximately lower half of the gaps between the conductive element wires 11a in the element harness 11 between the element wire crimping portion 32 and the sheath crimping portion 33, the approximately lower half of the gaps between the conductive element wires 11a in the tubular insulating sheath 12 at the end on the other end side of the electric wire 10 is continuously filled by the first portion 60A. At the position where the element wire crimping portion 32 is crimped to the element harness 11, the gaps between the conductive element wires 11a become extremely narrow due to the crimping. Therefore, the moisture-curing resin and curing accelerator applied as described above are unlikely to penetrate the side of the element wire crimping portion 32 (i.e., the far side of the second terminal 30) and are likely to penetrate the inner side of the tubular insulating sheath 12 (i.e., the near side of the second terminal 30). This also applies to the case where the second portion 60B of the sealing member 60 is provided as described later.

[0048] As described above, after the first portion 60A of the sealing member 60 is provided, the second portion 60B of the sealing member 60 applies a fluid moisture-curing resin to the element wire harness 11 exposed to the outside and located between the element wire crimping portion 32 and the sheath crimping portion 33 on the other end side of the electric wire 10 by using the nozzle 110, and allows the moisture-curing resin to penetrate into the gaps between the conductive element wires 11a (such as the gaps between the conductive element wires 11a). Figure 7 ), and then using the nozzle 120, a curing accelerator that promotes the curing of the resin is applied to the component wire harness 11 that is exposed to the outside and located between the component wire crimping portion 32 and the sheath crimping portion 33 on the other end side of the electric wire 10, and promotes the curing of the resin (as shown). Figure 8 The components are stacked on the first portion 60A in a manner as shown).

[0049] By providing the second portion 60B of the sealing member 60 in this manner, in this example, as shown in FIG. Figures 7 to 10 As shown, except for approximately the upper half area of ​​the gaps between the conductive element wires 11a in the element wire harness 11 between the element wire crimping portion 32 and the sheath crimping portion 33 (i.e., the remaining area except for the area filled with the first portion 60A), approximately the upper half area of ​​the gaps between the conductive element wires 11a in the tubular insulating sheath 12 at the end portion on the other end side of the electric wire 10 (i.e., the remaining area except for the area filled with the first portion 60A) is continuously filled with the second portion 60B.

[0050] Therefore, if Figure 9 and Figure 10As shown, except for the entire area of ​​the gaps between the conductive element wires 11a of the component wire harness 11 between the element wire crimping portion 32 and the sheath crimping portion 33, the entire area of ​​the gaps between the conductive element wires 11a in the tubular insulating sheath 12 at the end on the other end side of the electric wire 10 is continuously filled with the sealing member 60 (the sealing member 60 is equal to the first part 60A and the second part 60B). Therefore, the interior of the tubular insulating sheath 12 at the end on the other end side of the insulating sheath 12 of the electric wire 10 is sealed.

[0051] The reason for using a moisture-curable resin and a curing accelerator in combination in this example is as follows. When a resin having a high viscosity is used as the moisture-curable resin, the resin is less likely to penetrate between the conductive element lines 11a. On the other hand, when a resin having a low viscosity is used as the moisture-curable resin, the resin excessively diffuses to unnecessary places. In this regard, when a moisture-curable resin and a curing accelerator are used in combination, even if a resin having a low viscosity is used, when the resin diffuses to an appropriate range, the resin is cured by the curing accelerator, and therefore the resin does not diffuse to unnecessary places and can appropriately penetrate into the gaps between the conductive element lines 11a.

[0052] In this example, the curing accelerator is applied after the moisture-curing resin is applied. Therefore, the curing accelerator is applied after the resin has sufficiently penetrated into the gaps between the conductive element wires 11 a , which is preferable from the perspective of properly sealing the interior of the tubular insulating sheath 12 .

[0053] In addition, in this example, the application of the moisture-curing resin and the application of the curing accelerator are repeated twice (many times). By repeating the application many times in this way, the amount of the resin applied once can be reduced, and therefore the moisture-curing resin can be cured more reliably in a shorter time.

[0054] As a wet-curing resin having fluidity, for example, a resin containing cyanoacrylate as a main component (resin for instant bonding) is used. The viscosity of the wet-curing resin having fluidity is preferably 5 mPa·s or less at room temperature before curing, and more preferably 2 mPa·s or more and 5 mPa·s or less. As described above, by using a wet-curing resin having a suitably low viscosity that allows the resin to quickly penetrate into the gaps between the conductive element wires 11a to suitably fill the gaps in the tubular insulating sheath 12 at the end on the other end side of the electric wire 1, the sealing member 60 can be formed. By using a resin containing cyanoacrylate as a main component as the wet-curing resin, the curing waiting time of the resin can be shortened, and the productivity of the electric wire 1 equipped with a terminal can be improved. In addition, as a curing accelerator, a solvent containing an acetone-based organic solvent as a main component, a cyclopentane-based organic solvent, n-hexane (a petroleum-based solvent), etc. can be used.

[0055] Furthermore, as described above, after the anti-corrosion member 50 is provided on one end of the electric wire 10, the sealing member 60 is provided on the other end of the electric wire 10, whereby even when the sealing member 60 is formed of a moisture-curing resin having a relatively low viscosity, the sealing member 60 is less likely to enter the interior of the tubular insulating sheath 12 at the other end side of the electric wire 10 because the ingress and egress of air is restricted by the anti-corrosion member 50 at one end of the electric wire 10. In other words, the sealing member 60 can be retained between the conductive element wires 11a near the other end of the electric wire 10. Therefore, the softness of the electric wire 10 is prevented from being damaged by the sealing member 60 excessively entering the interior of the tubular insulating sheath 12 on the other end side of the electric wire 10. As described above, after the anti-corrosion member 50 is provided on one end of the electric wire 10, the sealing member 60 is provided on the other end of the electric wire 10, thereby completing Figure 11 The terminal-equipped electric wire 1 is shown in FIG.

[0056] like Figure 11 As shown, in the completed terminal-equipped electric wire 1, the first terminal 20 is housed in the terminal accommodating chamber of the connector housing 70, and the second terminal 30 is housed in the terminal accommodating chamber of the connector housing 80, thereby forming the wiring harness 2. The connector housing 70 is assembled to a mating connector provided in a device arranged in the interior of a vehicle with a relatively low probability of exposure to water, and the connector housing 80 is assembled to a mating connector provided in an electrical junction box arranged in the engine compartment 90 of the vehicle with a possibility of exposure to water. Thus, the wiring of the wiring harness 2 to the vehicle is completed.

[0057] Below, from the perspective of waterproofing, it is assumed that the electrical junction box to which the connector housing 80 is connected itself has high sealing performance. In this case, when the engine being driven stops, for example, the air temperature in the electrical junction box drops sharply, and therefore, the air pressure in the electrical junction box may be lower than the air pressure in the vehicle interior (i.e., negative pressure may be generated). In the terminal-equipped electric wire 1, the gaps between the conductive element wires 11a are sealed by a sealing member 60 at the other end of the electric wire 10 (i.e., the end where the second terminal 30 is provided), and the element wire harness 11 is covered by an anti-corrosion member 50 at one end of the electric wire (i.e., the end where the first terminal 20 is provided), thereby preventing moisture, such as humidity, from being drawn from the end of the electric wire 10 on the non-waterproof connector side where the first terminal 20 is provided, through the gaps between the conductive element wires 11a in the electric wire 10 toward the waterproof connector side where the second terminal 30 is provided. In this way, water can be prevented from entering through the tubular insulating sheath 12 of the electric wire 10 due to the negative pressure caused by the above-mentioned temperature fluctuation.

[0058] <Operations and Effects>

[0059] As described above, according to the manufacturing method for a terminal-equipped electric wire 1 according to this embodiment, after the terminals (i.e., first terminal 20 and second terminal 30) are crimped to both ends of the electric wire 10, in the first waterproofing step, at one end of the electric wire 10 to which the non-waterproof first terminal 20, which does not include a waterproof sealing member, is crimped, an anti-corrosion member 50 is provided to cover the component wire harness 11 exposed from the insulating sheath 12, thereby isolating the component wire harness 11 from the outside air. Meanwhile, in the second waterproofing step, at the other end of the electric wire 10 to which the waterproof second terminal 30 is crimped, a sealing member 60 is provided to fill the gaps between the conductive component wires 11a in the tubular insulating sheath 12 and seal the interior of the tubular insulating sheath 12. The combined use of a moisture-curable resin and a curing accelerator allows the second waterproofing step to be performed rapidly. Furthermore, since the gaps between the conductive component wires 11a are sealed at the other end of the electric wire 10 (i.e., the end of the electric wire to which the waterproof second terminal 30 is attached), water intrusion caused by negative pressure due to the aforementioned temperature fluctuations can be prevented. Even if the other end of the electric wire 10 is not completely sealed, since one end of the electric wire 10 is covered with the corrosion-resistant member 50, the amount of water absorbed when negative pressure is generated is limited to a very small amount of water initially present in the tubular insulating sheath 12 of the electric wire 10. Therefore, the manufacturing method according to this embodiment can manufacture the electric wire 1 equipped with a terminal that can prevent water from entering the gaps between the conductive element wires 11a of the electric wire 10.

[0060] The order of the first waterproofing step and the second waterproofing step is not particularly limited. However, if the second waterproofing step is performed after the first waterproofing step, even if the sealing member 60 is formed of a material having a low viscosity sufficient to fill (e.g., penetrate) the gaps between the conductive element wires 11a, the anti-corrosion member 50 at one end of the wire 10 restricts the ingress and egress of air, and therefore, the sealing member 60 is less likely to enter the interior of the tubular insulating sheath 12. In other words, the sealing member 60 can be retained between the conductive element wires 11a near the other end of the wire 10. Therefore, the flexibility of the wire 10 is prevented from being impaired due to the sealing member 60 excessively entering the interior of the tubular insulating sheath 12.

[0061] Furthermore, in the second waterproofing step, the curing accelerator is applied after the moisture curing resin is applied. Applying the curing accelerator after the resin has sufficiently penetrated into the gaps between the conductive element wires 11a is preferred from the viewpoint of appropriately sealing the interior of the tubular insulating sheath 12.

[0062] <Other embodiments>

[0063] The present disclosure is not limited to the above-described embodiments, and various modifications may be employed within the scope of the present disclosure. For example, the present disclosure is not limited to the above-described embodiments, and modifications and improvements may be made as appropriate. Furthermore, the materials, shapes, sizes, numbers, and configurations of components in the above-described embodiments are optional and not limiting, as long as the present disclosure can be implemented.

[0064] In the above embodiment, in the second waterproofing step, the curing accelerator is applied after the moisture-curing resin is applied. Alternatively, the moisture-curing resin can be applied after the curing accelerator. In this case, since the resin cures quickly when the moisture-curing resin is applied after the curing accelerator, it is preferable to perform the second waterproofing step quickly.

[0065] In addition, in the above embodiment, in the second waterproofing step, applying the moisture curable resin and applying the curing accelerator are repeated twice (multiple times). On the other hand, in the second waterproofing step, the moisture curable resin and the curing accelerator may be applied only once, respectively.

[0066] Furthermore, in the above-described embodiment, the corrosion-resistant member 50 is formed using an ultraviolet-curing resin. Alternatively, the corrosion-resistant member 50 may be formed using a resin other than an ultraviolet-curing resin. Similarly, the sealing member 60 is formed using a moisture-curing resin. Alternatively, the sealing member 60 may be formed using a resin other than a moisture-curing resin.

[0067] In addition, in the above embodiment, the second waterproofing step is performed after the first waterproofing step. On the other hand, the first waterproofing step may be performed after the second waterproofing step, or the first waterproofing step and the second waterproofing step may be performed simultaneously.

[0068] Here, features of an embodiment of the manufacturing method for the terminal-equipped electric wire 1 according to the present disclosure as described above will be briefly summarized and listed in the following [1] to [3].

[0069] [1] A method for manufacturing a terminal-equipped electric wire (1), the electric wire (1) comprising an electric wire (10), a first terminal (20), and a second terminal (30), the electric wire (10) comprising an element wire bundle (11) formed by bundling a plurality of conductive element wires (11a) and a tubular insulating sheath (12) covering the element wire bundle (11), the first terminal (20) being crimped to one end of the electric wire (10), and the second terminal (30) being crimped to the other end of the electric wire (10), the method comprising:

[0070] The step of crimping a first terminal (20) to one end of the electric wire (10) to electrically connect the component harness (11) exposed from one end of the electric wire (10) and the first terminal (20);

[0071] a step of crimping a second terminal (30) to the other end of the electric wire (10) so that an element wire crimping portion (32) of the second terminal (30) is crimped to an element wire harness (11) exposed from the other end of the electric wire (10), and a sheath crimping portion (33) of the second terminal (30) is crimped to a tubular sealing member (40) attached to the outer periphery of the other end of the electric wire (10);

[0072] a first waterproofing step of providing an anti-corrosion member (50) covering the component harness (11) at one end of the electric wire (10) to which the first terminal (20) is crimped to isolate the component harness (11) from the outside air; and

[0073] A second waterproofing step is to provide a sealing member (60) at the other end of the electric wire (10) to which the second terminal (30) is crimped, so as to fill the gap between the conductive element wires (11a) in the tubular insulating sheath (12) and seal the interior of the tubular insulating sheath (12), wherein

[0074] The second waterproofing step includes:

[0075] a step of applying a moisture-curable resin to the component wire harness (11) exposed to the outside and located between the component wire crimping portion (32) and the sheath crimping portion (33), and

[0076] A step of applying a curing accelerator that accelerates the curing of the moisture-curable resin to the component wire harness (11) exposed to the outside and located between the component wire crimping portion (32) and the sheath crimping portion (33).

[0077] According to a method for manufacturing a terminal-equipped electric wire having the structure of the above-mentioned [1], after the terminals (i.e., the first terminal and the second terminal) are crimped to the two ends of the electric wire, first, in a first waterproofing step, an anti-corrosion member is provided at one end of the electric wire to which the non-waterproof first terminal not including the sealing member is crimped, so as to cover the component wire bundle exposed from the insulating sheath to isolate the component wire bundle from the outside air. On the other hand, in a second waterproofing step, a sealing member is provided at the other end of the electric wire to which the waterproof second terminal including the sealing member is crimped, so as to fill the gap between the conductive element wires in the tubular insulating sheath and seal the tubular insulating sheath. Here, by using a moisture-curing resin and a curing accelerator in combination, the second waterproofing step can be carried out quickly. In addition, since the gap between the conductive element wires is sealed at the other end of the electric wire (i.e., the end of the electric wire to which the waterproof second terminal is attached), even if the other end of the electric wire is wired in a place where temperature fluctuations are large (such as an engine room), water can be prevented from entering due to the above-mentioned negative pressure. Even if the other end of the wire is not completely sealed, since one end of the wire is covered with the corrosion-resistant member, the amount of water absorbed when negative pressure is generated is limited to the very small amount of water initially present in the tubular insulating sheath of the wire. Therefore, according to the manufacturing method of this configuration, it is possible to manufacture a terminal-equipped wire that can prevent water from entering the gaps between the wire elements.

[0078] In the second waterproofing step, the order of applying the moisture-curing resin and the curing accelerator is not particularly limited. When the moisture-curing resin is applied first, the curing accelerator is applied after the resin has fully penetrated the gaps between the conductive element wires. This is preferred from the perspective of properly sealing the interior of the tubular insulating sheath. On the other hand, when the curing accelerator is applied first, the resin can be cured quickly when the moisture-curing resin is applied later, which is preferred from the perspective of expediting the second waterproofing step. Furthermore, in the second waterproofing step, the application of the moisture-curing resin and the curing accelerator can be repeated multiple times. By repeating this multiple times, the amount of resin applied at a time is reduced, and the moisture-curing resin can therefore be cured more reliably and in a shorter time.

[0079] [2] The manufacturing method according to [1] above, wherein

[0080] In the second waterproofing step, after the step of applying the moisture-curable resin to the component harness (11), the step of applying the curing accelerator to the component harness (11) is performed.

[0081] According to the method for manufacturing a terminal-equipped electric wire having the configuration described in [2] above, in the second waterproofing step, a curing accelerator is applied after applying the moisture-curing resin. The curing accelerator is applied after the resin has sufficiently penetrated into the gaps between the conductive element wires, which is preferable from the perspective of properly sealing the interior of the tubular insulating sheath.

[0082] [3] The manufacturing method according to [1] or [2] above, wherein

[0083] In the first waterproofing step, an anti-corrosion member (50) is provided by applying an ultraviolet curing resin to cover the element harness (11) and curing the ultraviolet curing resin,

[0084] In the second waterproofing step, a sealing member (60) is provided by applying a moisture-curing resin to the element wire harness (11) exposed to the outside and located between the element wire crimping portion (32) and the sheath crimping portion (33), causing the moisture-curing resin to penetrate into the interior of the tubular insulating sheath (12), and curing the moisture-curing resin.

[0085] The ultraviolet curable resin has a viscosity of 20 mPa·s or more at room temperature before curing, and

[0086] The moisture-curable resin has a viscosity of 5 mPa·s or less at room temperature before curing.

[0087] According to a manufacturing method for a terminal-equipped electric wire having a structure according to the above [3], an anti-corrosion member is provided at the end of the electric wire to which the first terminal (i.e., non-waterproof terminal) is attached by using an ultraviolet curing resin having a suitably high viscosity. Thus, an anti-corrosion member that suitably covers the periphery of the component wiring harness exposed from the insulating sheath can be formed while preventing liquid from dripping, excessive penetration into the component wiring harness, etc. On the other hand, a sealing member is provided at the end of the electric wire to which the second terminal (i.e., waterproof terminal) is attached by using a moisture-curing resin having a suitably low viscosity. Thus, a sealing member that allows the resin to quickly penetrate into the gap between the conductive element wires to suitably fill the gap in the tubular insulating sheath is formed. As described above, the "viscosity" can be measured, for example, in accordance with the viscosity test method specified in JIS K 7233. In addition, "room temperature" is a test temperature determined in this viscosity test method and is, for example, 25°C.

Claims

1. A method for manufacturing a terminal-equipped electric wire, the terminal-equipped electric wire comprising an electric wire, a first terminal, and a second terminal, the electric wire having an element wire bundle formed by bundling a plurality of conductive element wires and a tubular insulating sheath covering the element wire bundle, the first terminal being crimped to one end of the electric wire, and the second terminal being crimped to the other end of the electric wire, the method comprising: a step of crimping the first terminal to the one end of the electric wire to electrically connect the component wiring harness and the first terminal, the component wiring harness being exposed from the one end of the electric wire; a step of crimping the second terminal to the other end of the electric wire so that the element wire crimping portion of the second terminal is crimped to the element wire bundle exposed from the other end of the electric wire and the sheath crimping portion of the second terminal is crimped to a tubular sealing member attached to the outer periphery of the other end of the electric wire; a first waterproofing step of providing an anti-corrosion member at the one end of the electric wire to which the first terminal is crimped, the anti-corrosion member covering the component harness to isolate the component harness from outside air; and a second waterproofing step of providing a sealing member at the other end of the electric wire to which the second terminal is crimped so as to fill gaps between the conductive element wires in the tubular insulating sheath and seal the interior of the tubular insulating sheath, wherein The second waterproofing step includes: a step of applying a moisture-curable resin to the component wire harness exposed to the outside and located between the component wire crimping portion and the sheath crimping portion, and A step of applying a curing accelerator that accelerates curing of the moisture-curable resin to the component wire harness that is exposed to the outside and is located between the component wire crimping portion and the sheath crimping portion.

2. The manufacturing method according to claim 1, wherein In the second waterproofing step, the step of applying the curing accelerator to the component wiring harness is performed after the step of applying the moisture-curable resin to the component wiring harness.

3. The manufacturing method according to claim 1 or 2, wherein In the first waterproofing step, the corrosion-resistant member is provided by applying an ultraviolet curing resin to cover the element harness and curing the ultraviolet curing resin, In the second waterproofing step, the sealing member is provided by applying the moisture-curing resin to the element wire bundle exposed to the outside and located between the element wire crimping portion and the sheath crimping portion, causing the moisture-curing resin to penetrate into the interior of the tubular insulating sheath, and curing the moisture-curing resin. The ultraviolet curable resin has a viscosity of 20 mPa·s or more at room temperature before curing, The moisture-curable resin has a viscosity of 5 mPa·s or less at room temperature before curing.

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