JP2013120699A - Electric wire with terminal and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the water cut-off property of a portion between an insulation coating of an olefin resin and a waterproof resin part without requiring an increase in the man-hour of manufacturing and facilities in an electric wire with a terminal having the waterproof resin part covering a connection between an insulation electric wire and a metal terminal.SOLUTION: An electric wire 1 with a terminal includes: an insulation electric wire 10 having an insulation coating 12 of a polyolefin-based resin; an adhesion layer 30 formed on the surface of the insulation coating 12 over the entire circumference; and a waterproof resin part 40 formed by insert molding. The waterproof resin part 40 covers a region from a portion having the adhesion layer 30 in the insulation electric wire 10 formed therein to a connection 21 with a core wire 11 in a metal terminal 20. The adhesion layer 30 is a portion formed by shrinking a heat-shrinkable tube and has a two layer structure of an annual inner layer made of a polyamide-based resin and an annual outer layer made of a polyolefin-based resin or a nylon-based resin.

Description

  The present invention relates to an insulated wire and a terminal-attached wire including a metal terminal provided at an end portion of the insulated wire and a method for manufacturing the wire.

  In recent years, in wire harnesses mounted on automobiles, insulated wires and electric wires with terminals including metal terminals provided at the ends thereof are required to have higher waterproof performance. The electric wire with a terminal having a waterproof function includes a waterproof resin portion that covers the waterproof region at the end. Hereinafter, the electric wire with terminal provided with the waterproof resin portion is referred to as an electric wire with waterproof terminal.

  The waterproof resin portion is made of a synthetic resin material, and covers the protection region by insert molding with the protection region including the region from the insulating coating portion at the end of the insulated wire to the connection portion with the core wire in the metal terminal as the insert portion. It is a formed part.

  Moreover, in the manufacturing process of the electric wire with waterproof terminal, before the insert molding of the waterproof resin portion is performed, the adhesive is applied to the entire surface of the insulating coating at the end of the insulated wire. This adhesive serves as an adhesive layer that bonds the insulating coating and the waterproof resin portion while closing the gap between the insulating coating and the waterproof resin portion. This adhesive layer also functions as a water stop portion that prevents water from entering.

  In the electric wire with waterproof terminal, since the thermal expansion coefficient of the insulating coating and the thermal expansion coefficient of the waterproof resin portion are different, the adhesive layer has elasticity that can cope with the difference in thermal expansion between the insulating coating and the waterproof resin portion. There is a need. In general, as a material for an adhesive functioning as a water-stopping agent, a water-based and elastic silicone-based resin or rubber-based resin adhesive is used.

  However, when the insulated wire has an insulating coating of a polyolefin resin, which is an olefin resin, if an adhesive layer of a silicon resin or a rubber resin is employed, the adhesion between the insulating coating and the waterproof resin portion (waterproofing) ) Is insufficient. Therefore, it is easy for water to enter the connecting portion between the core wire and the metal terminal, and this water immersion causes corrosion and contact failure at the connecting portion between the core wire and the metal terminal.

  On the other hand, in Patent Document 1, in the manufacturing process of a waterproof terminal-attached electric wire, corona discharge treatment or plasma discharge treatment is applied to the insulation coating of the insulated wire, thereby improving the adhesion between the olefin-based resin insulation coating and the adhesive. It has been shown.

JP 2006-123458 A

  However, performing a corona discharge treatment or a plasma discharge treatment in a manufacturing process of a terminal-attached electric wire causes an increase in manufacturing man-hours and requires the introduction of expensive equipment.

  The present invention provides a terminal-attached electric wire having a waterproof resin portion that covers a connection portion between an insulated wire and a metal terminal, without requiring an increase in manufacturing man-hours and equipment, and between the insulation coating of the polyolefin resin and the waterproof resin portion. The purpose is to increase the water-stopping property of this part.

The electric wire with a terminal concerning the present invention is provided with each component shown below.
(1) A 1st component is an insulated wire which has a conductive core wire and the insulation coating of the polyolefin-type resin which covers the circumference | surroundings of this core wire.
(2) A 2nd component is a metal terminal electrically connected with the said core wire in the edge part of the said insulated wire.
(3) The third component is a portion formed by shrinking the heat shrinkable tube, and an annular inner layer made of polyamide resin and an annular outer layer made of polyolefin resin or nylon resin The adhesive layer is formed over the entire circumference on the surface of the insulating coating at the end of the insulated wire.
(4) The fourth component is made of aromatic nylon, and inserts a protective region including a region from at least a portion where the adhesive layer is formed in the insulated wire to a connection portion with the core wire in the metal terminal. The waterproof resin portion is formed so as to cover the protection region by insert molding.

  In the terminal-attached electric wire according to the present invention, the adhesive layer is preferably made of a material that causes elongation of 104.7% or more in an environment of −40 ° C. according to a test in accordance with JIS K6251.

  Moreover, in the electric wire with a terminal according to the present invention, it is desirable that the adhesive strength of the insulating coating and the adhesive layer is 183 kPa or more under an environment of 150 ° C. according to a test according to JIS K6850.

Moreover, this invention may be caught as invention of the method of manufacturing the electric wire with a terminal which concerns on this invention. That is, the manufacturing method suitable for manufacturing the electric wire with terminal according to the present invention includes the steps shown below.
(1) In the first step, a heat-shrinkable tube having a two-layer structure of an inner layer made of a polyamide resin and an outer layer made of a polyolefin resin or a nylon resin is formed at the end of the insulated wire. It is a heat-shrinkable tube placement step for placing the insulation coating at a position surrounding the portion.
(2) The second step is a bonding step in which the heat-shrinkable tube disposed in the insulating coating at the end of the insulated wire is bonded to the insulating coating of the insulated wire by heating.
(3) The third step is insert molding in which a resin material made of aromatic nylon is molded into the waterproof resin portion having a shape covering the protective region by insert molding using the protective region in the insulated wire as an insert portion. It is a process.

  According to the present invention, in a terminal-attached electric wire having a waterproof resin portion that covers a connection portion between an insulated wire and a metal terminal, the insulation coating of the polyolefin resin and the waterproof resin portion are not required without increasing the number of manufacturing steps and equipment. It is possible to increase the water stoppage of the portion between.

  Moreover, according to the manufacturing method which concerns on this invention, the lead time of manufacture of the electric wire with a terminal which concerns on this invention is shortened significantly so that it may mention later.

It is the top view and side view of the electric wire 1 with a terminal which concern on embodiment of this invention. It is sectional drawing of the part of the contact bonding layer in the electric wire 1 with a terminal. It is sectional drawing of the heat contraction tube used for manufacture of the electric wire 1 with a terminal. It is a schematic diagram which shows the manufacture procedure of the electric wire 1 with a terminal. It is a schematic diagram which shows the test method for evaluation of the waterproof performance of the electric wire 1 with a terminal. It is a figure which shows the evaluation result of the waterproof performance of the electric wire 1 with a terminal.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following embodiment is an example embodying the present invention, and is not an example of limiting the technical scope of the present invention.

<Embodiment>
First, the structure of the terminal-attached electric wire 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the terminal-attached electric wire 1 includes an insulated electric wire 10, a metal terminal 20, an adhesive layer 30, and a waterproof resin portion 40. 2 is a cross-sectional view of a portion of the adhesive layer 30 in the terminal-attached electric wire 1, and more specifically, a cross-sectional view of the terminal-attached electric wire 1 in the DD plane shown in FIG.

  The insulated wire 10 includes a conductive core wire 11 and an insulating coating 12 made of a polyolefin resin that covers the periphery of the core wire 11. In the insulated wire 10, the end of the core wire 11 is formed to extend from the end of the insulating coating 12.

  The core wire 11 is made of a metal material such as copper, a copper alloy, or an aluminum alloy, for example. On the other hand, the insulating coating 12 is made of, for example, a polyolefin resin such as crosslinked polyethylene or crosslinked polypropylene.

  The metal terminal 20 is a terminal electrically connected to the core wire 11 at the end of the insulated wire 10. The metal terminal 20 is a metal fitting made of a metal material such as copper or a copper alloy. The metal terminal 20 is a portion connected to a connection partner such as a bus bar, a terminal portion of an electrical equipment, or a terminal of another terminal-attached electric wire. In the example shown in FIG. 1, the metal terminal 20 is a flat terminal having a through hole through which a screw is passed. However, it is also conceivable that the metal terminal 20 has other shapes such as a plate shape or a rod shape without a through hole.

  For example, the metal terminal 20 is fixed to the core wire 11 at the end of the insulated wire 10 by ultrasonic welding or the like. Alternatively, when the metal terminal 20 is a crimp terminal in which a caulking portion is formed to be crimped to each of the core wire 11 and the insulating coating 12 of the insulated wire 10, the metal terminal 20 is crimped to the end of the insulated wire 10. To be fixed.

  The adhesive layer 30 is an adhesive layer formed on the entire surface of the insulating coating 12 at the end of the insulated wire 10. The adhesive layer 30 adheres the outer surface of the insulating coating 12 and the inner surface of the waterproof resin portion 40 and closes the gap between them. As will be described later, the adhesive layer 30 is a portion formed by shrinking a heat shrinkable tube.

  The waterproof resin portion 40 is a resin member that is formed so as to cover the protection region by insert molding using the predetermined protection region at the end of the terminal-attached electric wire 1 as an insert portion. The protection region is a region including at least a region from the portion of the insulated wire 10 where the adhesive layer 30 is formed to the connection portion 21 of the metal terminal 20 with the core wire 11.

  A feature of the terminal-attached electric wire 1 is that the adhesive layer 30 and the waterproof resin portion 40 are combined with the insulating coating 12 made of polyolefin resin, and the adhesive layer 30 has a two-layer structure. That is, as shown in FIG. 2, the adhesive layer 30 has a structure in which an annular inner layer 31 and an annular outer layer 32 of different materials are laminated.

  The inner layer 31 of the adhesive layer 30 is an annular layer made of polyamide resin. On the other hand, the outer layer 32 of the adhesive layer 30 is an annular layer made of polyolefin resin or nylon resin. As will be described later, the adhesive layer 30 having a two-layer structure is formed by heating and contracting a heat-shrinkable tube having a two-layer structure.

  The polyamide resin used as the material of the inner layer 31 in the adhesive layer 30 is, for example, 11 nylon or 12 nylon. Moreover, the polyolefin resin used as the material of the outer layer 32 in the adhesive layer 30 is, for example, an electron beam cross-linked soft flame retardant polyolefin resin. Moreover, the nylon resin used as the material of the outer layer 32 in the adhesive layer 30 is, for example, an electron beam cross-linked nylon resin.

<Method for producing electric wire 1 with terminal>
Next, the outline of the manufacturing procedure of the terminal-attached electric wire 1 will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view of a heat-shrinkable tube 30T used for manufacturing the terminal-attached electric wire 1. FIG. 4 is a schematic diagram showing the manufacturing procedure of the terminal-attached electric wire 1.

  In the manufacture of the terminal-attached electric wire 1, a heat-shrinkable tube 30 </ b> T having a two-layer structure is used as an adhesive that is a base of the adhesive layer 30. As shown in FIG. 3, the heat-shrinkable tube 30T includes a cylindrical outer cylindrical portion 32T and an inner adhesive layer 31T that is an adhesive layer formed on the entire inner surface of the outer cylindrical portion 32T.

  In the heat shrinkable tube 30T, the outer cylindrical portion 32T is a cylindrical member made of polyolefin resin or nylon resin. On the other hand, the inner adhesive layer 31T is an adhesive layer made of a polyamide-based resin. The outer cylindrical portion 32T is obtained by rapidly cooling a resin member formed into a very thin cylindrical shape by resin injection molding after being stretched into a thick cylindrical shape in a heated state. The outer cylindrical portion 32T obtained in this way has a shape memory characteristic that contracts to a thin cylindrical shape before being stretched when heated.

  In the manufacturing process of the terminal-attached electric wire 1, first, a tube insertion process and a terminal connection process are performed. As shown in FIG. 4A, the tube insertion step is a step of passing the insulated wire 10 through the hollow portion of the heat-shrinkable tube 30T. Moreover, a terminal connection process is a process of attaching the metal terminal 20 to the edge part of the insulated wire 10 by welding or caulking.

  By performing the tube insertion step and the terminal connection step, as shown in FIG. 4B, the core wire 11 of the insulated wire 10 and the metal terminal 20 in a state of passing through the heat shrinkable tube 30T are integrally connected. And electrically connected.

  In addition, it is normal that a tube insertion process is performed before a terminal connection process. However, when the contour shape of the inner surface of the heat-shrinkable tube 30T is formed larger than the contour shape of the metal terminal 20, the terminal connection step may be performed before the tube insertion step.

  In addition, in Fig.4 (a), the heat-shrinkable tube 30T before the insulated wire 10 penetrates is drawn with the virtual line (two-dot chain line). Moreover, in FIG.4 (b), the metal terminal 20 before connecting with the insulated wire 10 is drawn with the virtual line.

  Next, a tube moving process is performed. As shown in FIG. 4C, the tube moving step is a step of moving the heat-shrinkable tube 30 </ b> T before shrinkage through which the insulated wire 10 penetrates to the position of the insulating coating 12 part at the end of the insulated wire 10. is there. Therefore, the tube insertion step and the tube moving step are steps in which the heat-shrinkable tube 30T is disposed at a position surrounding the portion of the insulating coating 12 at the end of the insulated wire 10.

  In FIG. 4C, the heat-shrinkable tube 30T before being moved to the target position is drawn by a virtual line (two-dot chain line).

  Next, as shown in FIG. 4D, an adhesion process is performed. In the bonding step, the heat-shrinkable tube 30T disposed at the end of the insulated wire 10 at the end of the insulated wire 10 is heated by the heater 51 so that the heat-shrinkable tube 30T adheres to and adheres to the insulated coating 12 of the insulated wire 10. It is.

  By performing the bonding process, the adhesive layer 30 having a two-layer structure of the inner layer 31 made of polyamide resin and the outer layer 32 made of polyolefin resin or nylon resin is formed on the insulating coating 12 at the end of the insulated wire 10. Formed on the surface.

  The inner adhesive layer 31T of the heat shrinkable tube 30T is a thermoplastic synthetic resin, and is a so-called hot melt type adhesive. Therefore, the inner layer 31 of the adhesive layer 30 and the insulating coating 12 are welded by heating in the bonding process.

  By adopting the heat-shrinkable tube 30T, an application process for applying the adhesive diluted with a volatile solvent to the surface of the insulating coating 12 and a drying process for volatilizing the solvent are not necessary. In general, the drying process takes a long time to completely volatilize the solvent. Accordingly, the lead time for manufacturing the terminal-attached electric wire 1 is greatly shortened by eliminating the drying process.

  Finally, as shown in FIG. 4E, an insert molding process is performed. In the insert molding process, a molten resin material 40P made of aromatic nylon is molded into a waterproof resin portion 40 having a shape covering the protection region of the terminal-attached electric wire 1 by insert molding using the protection region in the insulated wire 10 as an insert portion. It is a process to do.

  In the insert molding step, first, the protection region of the terminal-attached electric wire 1 is disposed at a predetermined position inside the mold 52 for molding the waterproof resin portion 40. Thereafter, a molten resin material 40 </ b> P made of aromatic nylon is injected from the resin supply device 53 into the mold 52. Thereby, the waterproof resin part 40 of aromatic nylon is shape | molded in the shape which covers the protection area | region of the electric wire 1 with a terminal.

  4E is a cross-sectional view of the mold 52. The mold 52 shown in FIG.

  The outer layer 32 of the adhesive layer 30 once solidified before the insert molding is temporarily softened by the heat of the molten resin in the insert molding and welded to the waterproof resin portion 40 that is a molded product. Thereby, the waterproof resin part 40 adhere | attached with the insulation coating 12 of the insulated wire 10 with the contact bonding layer 30 is formed.

  By the way, it is important that the adhesive layer 30 is not peeled off from the insulating coating 12 by the pressure received from the injected molten resin during the insert molding. That is, the adhesive strength of the insulating coating 12 and the adhesive layer 30 needs to exceed the maximum shear stress received from the molten resin during insert molding. In consideration of this, the adhesive strength between the insulating coating 12 and the adhesive layer 30, that is, the adhesive strength between the insulating coating 12 and the inner layer 31 of the adhesive layer 30 is 150 according to a test according to the JIS K6850 standard. It is desirable that it is 183 kPa or more under an environment (atmosphere temperature) of ° C.

<Effect>
The polyamide resin constituting the inner layer 31 of the adhesive layer 30 and the polyolefin resin constituting the insulating coating 12 are easily bonded to each other at the molecular level and are firmly bonded.

  Further, according to the evaluation test, even when the outer layer 32 of the adhesive layer 30 is either a polyolefin-based resin or a nylon-based resin, excellent water stoppage between the outer layer 32 and the waterproof resin portion 40, that is, It was found that strong bondability can be obtained.

  Moreover, the adhesive layer 30 composed of the polyamide-based resin and the polyolefin-based resin or the nylon-based resin has sufficient elasticity that can cope with the difference in thermal expansion between the insulating coating 12 and the waterproof resin portion 40, Excellent water resistance. Therefore, by adopting the terminal-attached electric wire 1, it is possible to increase the water stoppage of the portion between the insulating coating 12 and the waterproof resin portion 40. And when the electric wire 1 with a terminal is employ | adopted, the increase of the man-hour of manufacture and an installation is not required.

  Furthermore, the waterproof resin portion 40 made of aromatic nylon is excellent in oil resistance. Therefore, the electric wire with terminal 1 is also suitable for use in a place where oil such as engine oil or brake oil is assumed to be attached in an automobile. The adhesive layer 30 is also excellent in heat resistance. Therefore, the terminal-attached electric wire 1 is also suitable for use in a place where the temperature is high in an automobile.

  Further, a two-layer structure of polyamide resin and polyolefin resin or nylon resin can be easily formed by using a heat-shrinkable tube 30T having a two-layer structure. Therefore, in the step of forming the adhesive layer 30, the application step of applying the adhesive diluted with the volatile solvent to the surface of the insulating coating 12 and the drying step of volatilizing the solvent are not necessary. As a result, the lead time for manufacturing the electric wire with terminal 1 is greatly shortened.

  By the way, generally, the wire harness mounted in a motor vehicle is assumed to be used in an environment having a temperature ranging from −40 ° C. to 150 ° C. Moreover, the thickness of the insulation coating 12 in the insulated wire 10 is often 0.7 mm or less. Furthermore, in order to reduce the weight of the waterproof resin portion 40 as much as possible while satisfying the strength condition required for the waterproof resin portion 40, the thickness of the waterproof resin portion 40 is desirably about 1.0 mm.

  Therefore, in the electric wire with terminal 1 for an automobile, it is desirable that the adhesive layer 30 has a stretchability that fills the difference in thermal expansion between the insulating coating 12 and the waterproof resin portion 40 under the above-described conditions. . For this purpose, the adhesive layer 30 has an elongation of 104.7% or more under an environment (atmospheric temperature) of −40 ° C., which is the most severe environmental temperature in terms of stretchability, according to a test in accordance with JIS K6251. It is desirable to be made of a material that generates

<Evaluation test and evaluation results>
Hereinafter, the evaluation method and the evaluation result of the waterproof performance of the terminal-attached electric wire 1 will be described with reference to FIGS. 5 and 6. FIG. 5 is a schematic diagram illustrating a test method for evaluating the waterproof performance of the terminal-attached electric wire 1.

  The evaluation test of the waterproof performance of the electric wire with terminal 1 is different only in the structure and material of the adhesive layer as compared with the two types of electric wire with terminal 1 that are different only in the material of the outer layer 32 in the adhesive layer 30 and the electric wire with terminal 1. This is a test comparing two types of electric wires with other terminals. In the following description, the four types of terminal-attached electric wires to be evaluated are collectively referred to as an evaluation sample 2. Further, reference numeral 30 </ b> X shown in FIG. 5 represents an adhesive layer of the evaluation sample 2.

  In FIG. 5, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals.

  As shown in FIG. 5, in the evaluation sample 2, the end of the insulated wire 10 opposite to the side connected to the metal terminal 20 is aired to the inside of the insulating coating 12 by a closing material 8 such as a heat shrinkable tube. It is sealed so as not to enter.

  In the evaluation sample 2, the dimension L1 from the end of the waterproof resin portion 40 to the adhesive layer 30X is 2 mm. That is, the adhesive layer 30 </ b> X is formed at a position recessed 2 mm from the end of the waterproof resin portion 40. Furthermore, in the evaluation sample 2, the width L2 of the adhesive layer 30X is 10 mm. Moreover, in the evaluation sample 2 corresponding to the electric wire 1 with a terminal, the thickness of the inner layer in the adhesive layer 30X is 10 μm or more, and the thickness of the outer layer is 5 mm or more.

  Moreover, in the evaluation sample 2, the diameter of the core wire 11 is 2.4 mm, the thickness of the insulating coating 12 is 0.7 mm, and the thickness of the portion covering the insulating coating 12 in the waterproof resin portion 40 is 2.02 mm.

  Further, in the evaluation test, the part from the part of the waterproof resin part 40 to the end part of the insulated wire 10 on the side sealed with the closing material 8 in the evaluation sample 2 is inserted into the inside of the cylindrical member 9. Retained. Furthermore, one opening 91 of the cylindrical member 9 is sealed by the waterproof resin portion 40.

  In the evaluation test, an area from the tip metal terminal 20 to a part of the insulated wire 10 surrounded by the tubular member 9 in the evaluation sample 2 is immersed in the water 6 stored in the water tank 7. Further, in the evaluation test, compressed air having a pressure of a maximum of 100 kPa is supplied from the other opening 92 of the cylindrical member 9.

  In the evaluation test shown above, the case where no bubbles are generated from the gap between the waterproof resin portion 40 and the metal terminal 20 in the evaluation sample 2 is accepted (OK), and the case where bubbles are generated is rejected (NG). evaluated. Further, the evaluation test was performed under each of four patterns of test conditions EC1 to EC4 having different environmental temperatures (atmosphere temperatures).

  The first test condition EC1 is a condition in which the environmental temperature is maintained at room temperature (about 25 ° C.). The second test condition EC2 is a condition in which the environmental temperature is maintained at 150 ° C. The third test condition EC3 is a condition in which the environmental temperature is maintained at −40 ° C. The fourth test condition EC4 is a condition in which the environmental temperature changes between −40 ° C. and 100 ° C. in 5 minutes and is maintained at −40 ° C. or 100 ° C. for 30 minutes.

  FIG. 6 is a diagram showing the evaluation results of the waterproof performance of the terminal-attached electric wire 1. In FIG. 6, codes S1, S2, S3, and S4 are identification codes for four types of evaluation samples 2.

  1st evaluation sample S1 is the electric wire 1 with a terminal by which the outer side layer 32 of polyolefin resin was employ | adopted. Moreover, 2nd evaluation sample S2 is the electric wire 1 with a terminal by which the outer side layer 32 of the nylon-type resin was employ | adopted.

  On the other hand, the adhesive layer 30X of the third evaluation sample S3 is a layer of silicon adhesive. The adhesive layer 30X of the fourth evaluation sample S4 is a butyl rubber adhesive layer. In the third evaluation sample S3 and the fourth evaluation sample S4, the adhesive layer 30X is composed of one layer of adhesive.

  In FIG. 6, “OK” indicates that bubbles were not generated from the gap between the waterproof resin portion 40 and the metal terminal 20 in the evaluation sample 2, and “NG” indicates that bubbles were generated and failed. It shows that it was.

  As shown in FIG. 6, under the second test condition EC2 in which the environmental temperature was maintained at 150 ° C., good results were obtained in all of the four types of evaluation samples 2. However, under other environmental temperature conditions, good results are obtained only in the first evaluation sample S1 and the second evaluation sample S2, which are the electric wires with terminals 1 having the adhesive layer 30X having the two-layer structure, and the other evaluations. Good results were not obtained in samples S3 and S4. From the above evaluation results, the excellent water stoppage of the terminal-attached electric wire 1 was demonstrated.

DESCRIPTION OF SYMBOLS 1 Electric wire with a terminal 2 Evaluation sample EC1, EC2, EC3, EC4 Identification code of test conditions (temperature conditions) S1, S2, S3, S4 Evaluation sample identification code 6 Water 7 Water tank 8 Occlusion material 9 Cylindrical member 10 Insulated wire 11 Core wire DESCRIPTION OF SYMBOLS 12 Insulation coating 20 Metal terminal 21 Connection part 30,30X Adhesion layer 31 Inner layer 32 Outer layer 30T Heat shrinkable tube 31T Inner adhesion layer 32T Outer cylinder part 40 Waterproof resin part 40P Resin material 51 Heater 52 Mold 53 Resin supply apparatus 91, 92 Opening of cylindrical member

Claims (4)

An insulated wire having a conductive core wire and an insulation coating of polyolefin resin covering the periphery of the core wire;
A metal terminal electrically connected to the core wire at an end of the insulated wire;
The heat-shrinkable tube is a portion formed by shrinkage, and has a two-layer structure of an annular inner layer made of polyamide resin and an annular outer layer made of polyolefin resin or nylon resin, and the insulation An adhesive layer formed over the entire circumference on the surface of the insulating coating at the end of the wire;
It is made of aromatic nylon, and covers the protective region by insert molding with a protective region including at least a portion from the portion where the adhesive layer is formed in the insulated wire to a connecting portion with the core wire in the metal terminal as an insert portion. And a waterproof resin portion formed.   2. The electric wire with terminal according to claim 1, wherein the adhesive layer is made of a material that causes elongation of 104.7% or more under an environment of −40 ° C. according to a test in accordance with JIS K6251.   The electric wire with a terminal according to claim 1 or 2, wherein an adhesive strength of the insulating coating and the adhesive layer is 183 kPa or more under an environment of 150 ° C according to a test in accordance with JIS K6850. An insulated wire having a conductive core wire and a polyolefin-based resin insulation coating covering the periphery of the core wire, a metal terminal electrically connected to the core wire at an end of the insulated wire, and at least the adhesion in the insulated wire A waterproof resin portion formed so as to cover a protection region including a region from a portion where a layer is formed to a connection portion with the core wire in the metal terminal, and a method of manufacturing a terminal-attached electric wire comprising:
A heat-shrinkable tube having a two-layer structure of an inner layer made of polyamide resin and an outer layer made of polyolefin resin or nylon resin is arranged at a position surrounding the insulating coating portion at the end of the insulated wire Heat shrinking tube placement step to
An adhesion step of adhering the heat-shrinkable tube disposed in the portion of the insulating coating at the end of the insulated wire to the insulating coating of the insulated wire by heating;
An insert molding step of molding a resin material made of aromatic nylon into the waterproof resin portion having a shape covering the protection region by insert molding using the protection region in the insulated wire as an insert portion. The manufacturing method of the electric wire with a terminal to do.

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