JP2011113670A - Method for preventing corrosion of coated wire with terminal, and method for manufacturing coated wire with terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for preventing corrosion of a coated wire with a terminal, in which an anticorrosive is prevented from flowing into a connection part of the terminal with a counterpart terminal when corrosion protection treatment for applying the anticorrosive in a liquid state is performed on the connection part between a wire conductor and the terminal. <P>SOLUTION: Before performing the corrosion protection treatment of applying the anticorrosive 24 in the liquid state on the connection part between the wire conductor 18 and the terminal 14, a solid oil composition 22 is applied between a terminal connection 14c connected to the counterpart terminal of the terminal 14 and a wire connection connected to the wire conductor 18 of the terminal 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an anticorrosion method for a covered electric wire with a terminal and a manufacturing method for the covered electric wire with a terminal, and more specifically, an anticorrosion method for a covered electric wire with a terminal and a covering with a terminal suitable as an anticorrosion method for a connection portion between a wire conductor and a terminal. The present invention relates to an electric wire manufacturing method.

  Conventionally, many electric wires are routed in vehicles such as automobiles. As an electric wire routed in a vehicle such as an automobile, a covered electric wire formed by covering an outer periphery of a conductor made of a soft material of tough pitch copper or the like is often used. At the end of the covered electric wire, the insulator is peeled off to expose the conductor, and the terminal is connected to the exposed conductor. The terminal connected to the end of the covered wire is inserted and locked to the connector.

  When such an electric wire is routed in, for example, an engine room or an indoor environment in a flooded area, rust is likely to occur at the connection portion between the conductor and the terminal due to the influence of heat and water. Therefore, it is necessary to perform anticorrosion treatment on the connection portion between the conductor and the terminal in the electric wire routed in such a place.

  In order to prevent corrosion at the connection portion between the conductor and the terminal, for example, Patent Document 1 discloses that grease is injected into the connector in which the terminal connected to the conductor of the electric wire terminal is inserted and locked.

  In addition, in the case of the anticorrosion treatment, a liquid anticorrosive can be used in addition to the grease as long as it can be applied to the connection portion between the conductor and the terminal.

  Although it does not prevent corrosion at the connection portion between the conductor and the terminal, for example, Patent Document 2 discloses a rust preventive solution in which benzotriazole or the like is dissolved in an aqueous solvent or the like. This rust preventive liquid is suitable for rust-proofing the surface of copper or copper alloy.

Japanese Patent Laid-Open No. 05-159846 JP 2002-235184 A

  However, as in Patent Document 2, when a liquid anticorrosive agent is applied to the connection portion between the conductor and the terminal, the liquid anticorrosive agent also flows into the connection portion of the terminal connected to the counterpart terminal. There is a fear. If it does so, the problem that the contact resistance with the other party terminal rises will arise.

  The problem to be solved by the present invention is that the anticorrosive agent flows into the connection portion of the terminal with the mating terminal when the anticorrosive treatment is applied to the connection portion between the conductor of the electric wire and the terminal. It is providing the corrosion prevention method of the covered electric wire with a terminal and the manufacturing method of a covered electric wire with a terminal which prevent this.

  In order to solve the above-mentioned problems, a corrosion prevention method for a coated electric wire with a terminal according to the present invention includes: a terminal connecting portion connected to a mating terminal of the terminal; The gist is to apply a solid-state oil composition between the wire connection portion connected to the wire conductor of the terminal and then apply a liquid state anticorrosive to the wire connection portion.

In the anticorrosion method for the coated electric wire with terminal according to the present invention, the conductor cross-sectional area of the electric wire is preferably 1 mm ² or less.

  The method for manufacturing a terminal-attached electric wire according to the present invention includes a connection step of connecting a terminal to an end of an electric wire conductor, a terminal connection portion connected to a counterpart terminal of the terminal, and an electric wire connected to the electric wire conductor of the terminal. The gist of the invention is to have a pretreatment step of applying a solid oil composition between the connecting portion and a corrosion prevention step of applying a liquid state anticorrosive agent to the electric wire connecting portion after the pretreatment step. It is.

  According to the anticorrosion method for a coated electric wire with a terminal according to the present invention, a solid oil composition is applied between a terminal connecting portion connected to the other terminal of the terminal and an electric wire connecting portion connected to the electric wire conductor of the terminal. Then, since the liquid state anticorrosive agent is applied to the wire connection portion, the applied liquid state anticorrosive agent can be prevented from flowing into the terminal connection portion.

  At this time, since the solid oil composition applied between the terminal connection portion and the wire connection portion does not easily flow out even under the influence of heat, the solid oil composition does not flow out. It is possible to prevent the applied liquid state anticorrosive agent from flowing into the terminal connection portion by staying between the wire connection portion and the wire connection portion.

Moreover, since the solid oil composition applied between the terminal connection portion and the wire connection portion is easy to apply, the conductor cross-sectional area of the wire is 1 mm ² or less and the terminal connection portion or the wire connection portion is very small. Moreover, it can apply | coat reliably between a terminal connection part and an electric wire connection part.

  On the other hand, according to the method for manufacturing a covered electric wire with a terminal according to the present invention, after applying the solid oil composition between the terminal connecting portion and the electric wire connecting portion, the liquid anticorrosive agent is applied to the electric wire connecting portion. Therefore, the liquid state anticorrosive agent is prevented from flowing into the terminal connecting portion, and a covered covered electric wire with excellent connection reliability can be obtained.

It is a schematic diagram explaining the corrosion prevention method of the covered electric wire with a terminal concerning the present invention. It is a schematic diagram showing an example of the covered electric wire with a terminal. It is a schematic diagram explaining a corrosion test method.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  The anticorrosion method for a coated electric wire with a terminal according to the present invention (hereinafter sometimes referred to as the present anticorrosion method) is to apply a liquid anticorrosive to the coated electric wire with a terminal.

  As shown to Fig.1 (a), the covered electric wire 10 with a terminal is the terminal connected to the terminal of the electric wire conductor 18 of the covered electric wire 12 with which the insulator 20 was coat | covered by the outer periphery of the electric wire conductor 18, and the covered electric wire 12 14. In the covered wire 12, the insulator 20 is peeled off at the end to expose the wire conductor 18, and the terminal 14 is connected to the end of the exposed wire conductor 18.

  The terminal 14 is formed from a rectangular tube-shaped terminal connection portion 14c connected to the counterpart terminal and a base end 14d of the terminal connection portion 14c, and a wire barrel 14a for crimping the end of the wire conductor 18 of the covered wire 12. And an insulation barrel 14b that is further extended from the wire barrel 14a and crimps the insulator 20 at the end of the covered electric wire 12.

  In this anticorrosion method, as shown in FIG.1 (b), in the electric wire 10 with a terminal, it is solid between the terminal connection part 14c connected to the other party terminal, and the electric wire connection part connected to the electric wire conductor 18. After the oil composition 22 is applied, a liquid state anticorrosive agent 24 is applied to the wire connection portion.

  In the case of applying the solid oil composition 22, the space between the terminal connection portion 14c and the wire connection portion is from the tip of the wire conductor 18 at the wire end to the base end 14d of the rectangular tube-shaped terminal connection portion 14c. A space (region A in FIG. 1B). The range in which the solid oil composition 22 is applied may be the entire region A between them or a partial region. In short, the solid oil composition 22 may be applied to the portion connecting the terminal connection portion 14c and the wire connection portion. Moreover, as shown in FIG. 2, the solid oil composition 22 may block the opening of the base end 14d of the rectangular tube-shaped terminal connecting portion 14c.

  The solid oil composition is a solid composition containing oil, as long as the entire oil composition is solid, the oil itself may be solid, or a semi-solid or liquid oil The whole oil composition may be solidified by blending a composition other than oil. The term “solid” as used herein means that the liquid does not flow like a liquid but has a softness capable of changing its shape to the extent that it can be applied. Examples of the solid form include a jelly form. Moreover, the whole composition can be applied, and it is preferable that the whole composition has consistency.

  Examples of the oil include fats and oils and paraffin. Fats and oils are generally fatty acid esters, and fats and oils include fats that are solid at room temperature, fatty oils that are liquid at room temperature, and waxes. As fats and oils, any of solid fats and oils, semi-solid fats and oils, and liquid fats and oils may be sufficient. Moreover, it may consist of a combination of two or more of these. Similarly, the paraffin may be solid paraffin, semi-solid paraffin, or liquid paraffin. Moreover, it may consist of a combination of two or more of these.

  The solid oil composition 22 may be composed of a single oil, or may contain a composition other than oil. For example, when the oil is a semi-solid or liquid oil, it is preferable to add a thickener. As an additive which can be mix | blended with the solid oil composition 22, the additive etc. which are mix | blended with lubricating oil can be mentioned, for example. Moreover, as a thickener, what is mix | blended with lubricating oil etc. can be mentioned, for example.

  Specific examples of the solid oil composition 22 include grease and petrolatum.

  The coating method of the solid oil composition 22 is not particularly limited, and can be performed by various methods such as dropping and coating.

  In the case where the anticorrosive agent 24 is applied, the liquid state anticorrosive agent may be one in which the anticorrosive agent 24 is liquid at room temperature and can be applied as it is, or the anticorrosive agent 24 itself is at room temperature. Although it is solid, it may be liquefied at the time of application. Examples of the method for making a solid anticorrosive liquid at room temperature include a method of heating to a flowable temperature and a method of dissolving using a solvent.

  The range in which the anticorrosive agent 24 is applied is preferably a range that covers at least the exposed wire conductor 18 as shown in FIG. Further, the range where the anticorrosive agent 24 is applied may be a range where the exposed wire conductor 18 and the insulation barrel 14b are continuously covered.

  Specific examples of the anticorrosive agent 24 include a general rust preventive agent used for metals. In addition to this, for example, a resin composition mainly containing an ethylene-α-olefin copolymer can be exemplified.

  The resin composition mainly containing the ethylene-α olefin copolymer may be composed of the ethylene-α olefin copolymer alone, and if necessary, additives, The polymer may be contained.

  The ethylene-α-olefin copolymer has a melt flow rate (MFR) of 200 g / 10 min. At 190 ° C. and 21.18 N measured according to JIS K6922-1. The above is preferable. The MFR of the ethylene-α olefin copolymer is 200 g / 10 min. If it is less than 1, the fluidity is low, and the portion to be subjected to the anticorrosion treatment cannot be sufficiently covered, so that the anticorrosion effect cannot be sufficiently exhibited. Further, the MFR of the ethylene-α olefin copolymer is more preferably 500 g / 10 min. Or more, more preferably 1000 g / 10 min. That's it.

  The ethylene-α-olefin copolymer preferably has a copolymerization ratio of α-olefin of 10% by mass or more. When the copolymerization ratio of the α-olefin is less than 10% by mass, the affinity (wetting property) with the wire conductor and the terminal is not sufficient, and the anticorrosion effect cannot be sufficiently exhibited. Further, from the viewpoint of excellent anticorrosion effect, the copolymerization ratio of α-olefin is preferably 15% by mass or more, and more preferably 20% by mass or more.

  Preferred examples of the α-olefin in the ethylene-α-olefin copolymer include vinyl esters, α, β-unsaturated carboxylic acid alkyl esters, and carboxyl group-containing monomers. These α-olefins are particularly excellent in the effect of increasing the affinity (wetting properties) with the wire conductor and the terminal. The ethylene-α olefin copolymer may be a copolymer of ethylene and one kind of α olefin, or may be a copolymer of ethylene and two or more kinds of α olefins.

  Examples of the vinyl ester include vinyl propionate, vinyl acetate, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl stearate, vinyl trifluoroacetate, and the like.

  Examples of the α, β-unsaturated carboxylic acid alkyl ester include methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl methacrylate.

  Examples of the carboxyl group-containing monomer include maleic anhydride.

  Specific examples of suitable ethylene-α olefin copolymers include ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), and ethylene-methyl acrylate copolymer. (EMA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-methyl acrylate-maleic anhydride-modified copolymer (maleic anhydride-modified EMA), and the like.

  In the anticorrosive agent 24, the additive that can be added as necessary is not particularly limited as long as it is an additive generally used for a resin molding material. Specifically, for example, inorganic fillers, antioxidants, metal deactivators (copper damage inhibitors), UV absorbers, UV masking agents, flame retardant aids, processing aids (lubricants, waxes, etc.), Examples thereof include carbon and other coloring pigments.

  In the case where the anticorrosive agent 24 is a resin composition mainly containing an ethylene-α olefin copolymer, polymer components other than the ethylene-α olefin copolymer may be blended as necessary. good.

  The ethylene-α-olefin copolymer and the polymer component blended as necessary may be cross-linked as necessary for the purpose of increasing heat resistance and mechanical strength. There are no particular limitations on the means of crosslinking, such as thermal crosslinking, chemical crosslinking, silane crosslinking, electron beam crosslinking, and ultraviolet crosslinking. In addition, what is necessary is just to perform the bridge | crosslinking process of anticorrosive, after covering the part which performs anticorrosion with the anticorrosive which concerns on this invention.

  After application of the anticorrosive agent 24, a film is formed by the anticorrosive agent 24. The thickness of the coating of the anticorrosive agent 24 may be adjusted as appropriate, but is preferably in the range of 0.01 mm to 0.1 mm. If the coating is too thick, it is difficult to insert the terminal 14 into the connector. On the other hand, if the thickness of the coating is too thin, the anticorrosion effect tends to decrease.

  If the electrical connection is not affected, the anticorrosive agent 24 is also applied to the back surface side of the rectangular tube-shaped terminal connection portion 14c protruding from the wire barrel 14a of the terminal 14 and the back surface side of the wire barrel 14a and the insulation barrel 14b. You may form the film.

  In the case where the anticorrosive agent 24 is made of a resin composition mainly containing an ethylene-α-olefin copolymer, it is sufficient that the anticorrosive agent 24 can flow to the extent that it can be applied.

  The electric wire conductor 18 is formed of a stranded wire formed by twisting a plurality of strands 18a. In this case, the stranded wire may be composed of one type of metal strand, or may be composed of two or more types of metal strand. Moreover, the twisted wire may contain the strand etc. which consist of organic fibers other than a metal strand. Note that “consisting of one kind of metal strand” means that all the metal strands constituting the stranded wire are made of the same metal material, and “consisting of two or more types of metal strands” This means that the wire contains metal wires made of different metal materials. The stranded wire may include a reinforcing wire (tension member) that reinforces the covered electric wire.

  Examples of the material of the metal strand include copper, copper alloy, aluminum, aluminum alloy, or materials obtained by applying various platings to these materials. Examples of the material of the metal strand as the reinforcing wire include copper alloy, titanium, tungsten, and stainless steel. Examples of the organic fiber as the reinforcing wire include aramid fibers such as Kevlar (registered trademark of DuPont).

  Examples of the material of the insulator 20 include rubber, polyolefin, PVC, and thermoplastic elastomer. These may be used alone or in combination of two or more. Various additives may be appropriately added to the material of the insulator 20. Examples of the additive include a flame retardant, a filler, a colorant and the like.

  As a material (material for the base material) of the terminal 14, various copper alloys, copper, etc. can be used in addition to brass that is generally used. A part (for example, a contact) or the entire surface of the terminal 14 may be plated with various metals such as tin, nickel, and gold.

  The wire connection portion between the wire conductor 18 and the terminal 14 may be made of the same kind of metal, for example, a combination of a copper wire and a copper terminal, or a combination of an aluminum wire and a copper terminal, for example. In this way, it may be made of different metals.

The thickness of the covered wire 12 and the size of the terminal 14 to which the present anticorrosion method is applied are not particularly limited, but the covered wire 12 is a thin wire having a conductor cross-sectional area of 1 mm ² or less, and a terminal 14 has a characteristic that can be applied to a relatively small covered electric wire with a terminal having a width of the terminal connecting portion 14c of 2.3 mm or less. This is because it is possible to apply the solid oil composition 22 between the terminal connection portion 14c and the wire connection portion even if it is a relatively small covered electric wire with a terminal.

  According to the anticorrosion method of the above configuration, the solid oil composition 22 is applied between the terminal connection portion 14c connected to the counterpart terminal of the terminal 14 and the wire connection portion connected to the wire conductor 18 of the terminal 14. After that, since the liquid state anticorrosive agent 24 is applied to the wire connection portion, the applied liquid state anticorrosive agent 24 can be prevented from flowing into the terminal connection portion 14c.

  At this time, since the solid oil composition 22 applied between the terminal connection portion 14c and the wire connection portion does not easily flow out even when affected by heat, the solid oil composition 22 does not flow out. It stays between the terminal connection part 14c and the electric wire connection part, and it can prevent that the apply | coated liquid state anticorrosive 24 flows into the terminal connection part 14c.

Moreover, since the solid oil composition 22 applied between the terminal connection portion 14c and the wire connection portion is easy to apply, the conductor cross-sectional area of the wire is 1 mm ² or less, and the terminal connection portion 14c and the wire connection portion are very Even when it is small, it can be reliably applied between the terminal connection portion 14c and the wire connection portion.

  Next, the manufacturing method of the covered electric wire with a terminal which concerns on this invention is demonstrated.

  In the method for manufacturing a coated electric wire with a terminal according to the present invention, before applying the solid oil composition 22 between the connecting step of connecting the terminal 14 to the end of the electric wire conductor 18 and the terminal connecting portion 14c and the electric wire connecting portion. It has a processing process and the anticorrosion process of apply | coating the anticorrosive agent 24 to an electric wire connection part.

  In the connecting step, first, the insulator 20 is peeled off at the end of the covered wire 12 to expose the wire conductor 18. Next, the terminal 14 is connected to the exposed wire conductor 18. As a method for connecting the wire conductor 18 and the terminal 14, as shown in FIG. 1A, a crimp connection method in which the outer periphery of the exposed wire conductor 18 is crimped with a wire barrel 14 a may be used, or the exposed wire conductor 18. Various connection methods may be used in which the terminal 14 and the terminal 14 are pressed, welded (resistance welding, ultrasonic welding, etc.), or soldered.

  In the pretreatment step, the solid oil composition 22 is applied between the terminal connection portion 14c and the wire connection portion before applying the anticorrosive agent 24 to the wire connection portion. The application method of the solid oil composition 22 is not particularly limited, and a method such as application by dripping or brushing can be employed.

  In the anticorrosion step, after the pretreatment, the anticorrosive agent 24 is applied to the wire connection portion. The application method of the anticorrosive agent 24 is not particularly limited, and a method such as application by dripping or brushing can be employed. Moreover, when the anticorrosive agent 24 consists of a resin composition, methods, such as extrusion molding, are employable.

  In addition, in the manufacturing method of the covered electric wire with a terminal which concerns on this invention, the above-mentioned covered electric wire with a terminal, a solid oil composition, and an anticorrosive can be used suitably.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by an Example.

(Preparation of covered electric wire)
100 parts by weight of polyvinyl chloride (degree of polymerization 1300), 40 parts by weight of diisononyl phthalate as plasticizer, 20 parts by weight of calcium bicarbonate as filler, 5 parts by weight of calcium zinc stabilizer as stabilizer at 180 ° C. in an open roll The mixture was mixed and molded into pellets with a pelletizer to prepare a polyvinyl chloride composition. Next, with a 50 mm extruder, the periphery of a conductor (cross-sectional area 0.75 mm) made of an aluminum alloy twisted wire in which seven aluminum alloy wires are twisted is extruded to a thickness of 0.28 mm with the obtained polyvinyl chloride composition. It coat | covered and the covered electric wire (PVC electric wire) was produced.

(Production of coated electric wire with terminal)
After peeling off the end of the produced covered wire and exposing the wire conductor, a brass female crimp terminal (tab width 0.64 mm), which is widely used for automobiles, was crimped and crimped to the end of the covered wire. . Subsequently, the following solid oil composition was apply | coated between the terminal connection part and the electric wire connection part. Next, the following various anticorrosives were applied to the connection portion between the wire conductor and the terminal, and the exposed wire conductor and the barrel of the terminal were covered with various anticorrosives. In addition, when apply | coating various anticorrosive agents, various anticorrosive agents were heated at 230 degreeC and made it liquid state. Moreover, the thickness of the coating film was 0.05 mm.

(Solid oil composition)
・ Grease <1> [manufactured by Nippon Oil, "Pyronock WH-1"]
・ Grease <2> [manufactured by Nippon Oil Corporation, "Pyroknock Grease 1"]

(Anticorrosive)
EVA (ethylene-vinyl acetate copolymer) [Mitsui DuPont Polychemicals, Evaflex EV205W (comonomer 14% by mass, MFR800)]
EEA (ethylene-ethyl acrylate copolymer) [manufactured by Nippon Unicar, NUC-6090 (comonomer 30 mass%, MFR 1250)]

(Anti-corrosion test method)
As shown in FIG. 3, the covered electric wire 1 with a terminal is connected to the positive electrode of the 12 V power source 2, and the pure copper plate 3 (1 cm × 2 cm × 1 mm) is connected to the negative electrode of the 12 V power source 2, The connection portion between the conductor and the terminal and the pure copper plate 3 were immersed in 300 cc NaCl 5% aqueous solution 4 and energized at 12 V for 2 minutes. After energization, ICP emission analysis of NaCl 5% aqueous solution 4 was performed, and the amount of aluminum ions eluted from the wire conductor of the covered wire 1 with terminals was measured. The case where the elution amount was less than 0.1 ppm was “◯”, and the case where the elution amount was 0.1 ppm or more was “x”.

(Electrical connection test method)
After fitting and connecting the female terminal of the obtained covered electric wire with terminal and the male terminal prepared separately, whether there is an electrical connection between the electric wire conductor of the covered electric wire with terminal and the male terminal confirmed. Specifically, the resistance value was measured by bringing a probe into contact with both conductor exposed portions (using a resistance value measurement method called a four-terminal method). In this case, when the resistance value is 1Ω or less, “◯” is a good electrical connection, and when the resistance value is larger than that, the connection failure is “X”.

  In Comparative Example 1, it was confirmed that the electrical connectivity was inferior. On the other hand, according to the Example, it has confirmed that it was excellent in both anticorrosion property and electrical connectivity.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

  For example, in the covered electric wire with terminal 10 represented in the above embodiment, a female terminal having a rectangular tube-shaped terminal connecting portion 14c is shown as the terminal 14, but the present invention is not limited to this. For example, it may be a male terminal that can be fitted with a female terminal, or a tuning fork terminal. Moreover, the terminal 14 may be crimped only by the wire barrel 14a without having the insulation barrel 14b. Moreover, in the said embodiment, although the conductor 18 which consists of a twisted wire is shown, the conductor 18 may be a single core wire.

DESCRIPTION OF SYMBOLS 10 Coated electric wire with terminal 12 Coated electric wire 14 Terminal 18 Electric wire conductor 20 Insulator 22 Solid oil composition 24 Anticorrosive

Claims (3)

  In the electric wire with a terminal in which the terminal is connected to the terminal of the electric wire conductor, solid oil is provided between the terminal connecting portion connected to the counterpart terminal of the terminal and the electric wire connecting portion connected to the electric wire conductor of the terminal. After apply | coating a composition, the anticorrosive of a liquid state is apply | coated to the said electric wire connection part, The anticorrosion method of the electric wire with a terminal characterized by the above-mentioned. The method for preventing corrosion of a terminal-attached electric wire according to claim 1, wherein a conductor cross-sectional area of the electric wire is 1 mm ² or less. A connection step of connecting the terminal to the end of the wire conductor;
A pretreatment step of applying a solid oil composition between a terminal connection portion connected to a counterpart terminal of the terminal and a wire connection portion connected to the wire conductor of the terminal;
The manufacturing method of the electric wire with a terminal characterized by having the anticorrosion process of apply | coating a liquid state anticorrosive agent to the said electric wire connection part after the said pre-processing process.

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