JP2013251166A - Wire harness and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire harness capable of preventing migration of a plasticizer to a water cutoff part of a wire harness and reduction in water cutoff performance, and thereby, exhibiting a good water cutoff performance over the long term, and to provide a method of manufacturing the same.SOLUTION: A wire harness 1 is configured to have a wire bundle 7 obtained by bundling a plurality of insulation electric wires 4 each obtained by coating a conductor 2 with a coating material 3 consisting of an insulator. The wire harness 1 is provided with a water cutoff part 10 in which a surface of a water cutoff agent 40 is coated by a protection sheet 30. The water cutoff part 10 is obtained by supplying the water cutoff agent 40 consisting of an ultraviolet ray curable resin to which a plasticizer of the same kind as that contained in the coating material 3 is added, to a conductor exposure part 5 obtained by removing a part of the coating material 3, and performing light irradiation in a state that the surface of the water cutoff agent 40 is coated by the light transmissive protection sheet 30 to cure the water cutoff agent 40.

Description

  TECHNICAL FIELD The present invention relates to a wire harness and a method for manufacturing the same, and more specifically, an intermediate splice portion of an electric wire or shielded wire used in an automobile wire harness or the like, a water stopping method for an intermediate coating removal portion or a terminal portion of the electric wire, etc. The present invention relates to a wire harness that is suitably used for the manufacturing method and a manufacturing method thereof.

  Conventionally, for example, a method described in Patent Document 1 described below is known as a water stopping method for an intermediate splice part of an automobile wire harness or the like.

  In the method described in Patent Document 1, a splice portion coated with an adhesive material of an insulating resin sheet is placed, a low-viscosity photocurable silicone resin having a viscosity of about 10 Pa · s to 100 Pa · s is applied, and the insulating resin is applied. This is a method in which a sheet is wound around a splice portion to cure a silicone resin.

  Moreover, this inventor apply | coats the curable resin composition which has photocurability and thermosetting to a water stop part as an improvement technique of the wire harness of the said patent document 1, and light permeate | transmits this water stop part. A protective sheet (wrap film) having a property is wound and light is irradiated from above the protective sheet to cure the surface layer part of the curable resin composition, and then heated to cure the inside of the water stop part. A wire harness has been proposed first (Japanese Patent Application No. 2011-122026, filed on May 31, 2011).

JP 2009-136039 A

  In wire harnesses, waterproofing of the splice part needs to protect not only the conductor part such as copper of the splice part itself but also the electric wire (coating material) for waterproofing. Conventionally, as a covering material, a vinyl chloride resin which is a balanced material has been used in terms of on-vehicle environmental characteristics. Usually, a plasticizer is added to the vinyl chloride resin from the viewpoint of improving low-temperature brittleness.

  For this reason, when the water stop part of a wire harness becomes high temperature, the plasticizer contained in a vinyl chloride resin will transfer to resin of a water stop agent rapidly. When the plasticizer of the covering material shifts to the water-stopping resin, the adhesive force at the interface between the water-stopping covering material and the water-stopping agent decreases. Further, when the plasticizer is reduced from the covering material, the electric wire becomes thin and thin, and a water intrusion path is generated.

  Thus, in the said prior art, when the plasticizer of the coating | covering material of the insulated wire moved to the water stop agent side, there existed a problem that the airtightness required for waterproofing will be impaired and water stop performance fell.

  The object of the present invention is to solve the above-mentioned problems of the prior art, and prevents the water-stopping performance from deteriorating due to the migration of the plasticizer in the water-stop portion of the wire harness. Is to provide a wire harness and a method of manufacturing the same.

In order to solve the above problems, the wire harness of the present invention is
A conductor exposed portion having an electric wire bundle in which a plurality of insulated electric wires whose conductors are covered with a covering material made of an insulating material is bundled, in which a part of the covering material is removed and an internal conductor is exposed is an ultraviolet curable resin A wire harness having a water stop portion that is covered with a water stop agent, and the surface of the water stop agent is covered with a light-transmitting protective sheet,
The gist is that a plasticizer of the same type as the plasticizer contained in the wire covering material is added to the waterstop agent.

  The said wire harness WHEREIN: It is preferable that content of the plasticizer added to the said water stop agent exists in the range of 5-15 mass% in the said water stop agent.

  The said wire harness WHEREIN: It is preferable that the said water stop agent of the said water stop part has coat | covered the surface of the said coating | covering material adjacent to the said conductor exposed part.

  The said wire harness WHEREIN: It is preferable that the adhesive strength of the said water stop agent and the said coating | covering material is 500 N / m or more by 120 degreeC and the peeling adhesive strength after a 120-hour process.

The manufacturing method of the wire harness of the present invention is as follows:
A conductor exposed portion having an electric wire bundle in which a plurality of insulated electric wires whose conductors are covered with a covering material made of an insulating material is bundled, in which a part of the covering material is removed and an internal conductor is exposed is an ultraviolet curable resin A wire harness manufacturing method having a water stop portion coated with a water stop agent, wherein the surface of the water stop agent is covered with a light-transmitting protective sheet,
Using a water-stopping agent to which a plasticizer of the same type as the plasticizer contained in the covering material is added, supplying the water-stopping agent to the water-stopping portion, and using a protective sheet having light permeability, The gist is to cure the water-stopping agent by irradiating light with the surface covered.

  In the wire harness of the present invention, the plasticizer of the same kind as the plasticizer contained in the covering material of the insulated wire is added to the waterstop agent, so that the plasticizer of the waterstop portion of the wire harness is in the waterstop portion. It is possible to suppress the migration, and it is possible to prevent the plasticizer from migrating to the water-stopping portion and lower the water-stopping performance, thereby exhibiting a good water-stopping performance over a long period of time.

  The wire harness manufacturing method of the present invention uses a water-stopping agent to which a plasticizer of the same type as the plasticizer contained in the covering material is added, supplies the water-stopping agent to the water-stop portion, and transmits light. By adopting a method of irradiating light with the protective sheet having a surface covering the surface of the water-stopping agent and curing the water-stopping agent, the transition of the plasticizer from the coating material to the water-stopping portion is improved. It is possible to reliably provide the wire harness that is excellent in water stopping performance.

FIG. 1 is a perspective view showing an external appearance in the vicinity of a water stop middle splice part of an example of the wire harness of the present invention. FIG. 2 is a horizontal sectional view taken along line AA of FIG. 3A to 3C show an example of the manufacturing process of the wire harness of the present invention, and are explanatory diagrams in the vicinity of the water stop middle splice. 4 (a) to 4 (e) show manufacturing steps of another example of the method for manufacturing the wire harness of the present invention, and are explanatory diagrams in the vicinity of the water stop intermediate splice portion.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an external appearance of an example of a wire harness according to the present invention in the vicinity of an intermediate splice portion, and FIG. 2 is a horizontal sectional view taken along line AA of FIG. As shown in FIGS. 1 and 2, the wire harness 1 of the present invention is an electric wire bundle in which four insulated wires 4 covered with a covering material 3 made of an insulator are bundled around a conductor 2 made of a core wire. It is configured.

  The intermediate splice portion 20 of the wire harness 1 has a conductor exposed portion 5 in which the insulated wires 3 of the wire bundle are peeled off and the internal conductor 2 is exposed. In the conductor exposed portion 5, the conductors 2, 2, 2, 2 of the plurality of insulated wires 4, 4, 4, 4 are joined and electrically connected.

  The wire harness 1 is configured as a water-stop intermediate splice portion 10 (hereinafter sometimes simply referred to as the water-stop portion 10) by surrounding the intermediate splice portion 20 with a protective sheet 30 and a water-stop agent 40.

  The protective sheet 30 has flexibility that can be deformed following the deformation of the surface of the water stopping agent 40 of the water stopping unit 10. The protective sheet 3 covers the periphery of the water-stopping agent 40 in a state of being in close contact with the surface of the water-stopping agent 40. The water stop agent of the water stop portion 10 is cured by being irradiated with ultraviolet rays while penetrating into the conductor exposed portion 5 of the insulated wire.

  Further, the water-stopping agent 40 of the water-stopping portion 10 is cured in a state of being in close contact with the surface of the covering material 3 of the insulated wire 4 adjacent to the conductor exposed portion 5. In the water stop part 10, the water stop agent 40 covers the covering part 6 before and after the conductor adjacent to the conductor exposed part of the insulated electric wire 4. Thus, the water-stopping agent 40 covers the covering portion 6, thereby preventing moisture from entering from the gap between the covering material 3 and the conductor 2.

  As the covering material 3 of the insulated wire 4, a soft vinyl chloride resin composed of a vinyl chloride resin and a plasticizer is used. Examples of the plasticizer include phthalate ester plasticizers such as didiisononyl phthalate (DINP), trimellitic acid ester plasticizers such as tri-2-ethylhexyl trimellate, 2-ethylhexyl adipate, dibutyl sebacate, and the like. Aliphatic dibasic acid ester plasticizers, epoxy plasticizers such as epoxidized soybean oil, and phosphate ester plasticizers such as tricresyl phosphate. Among them, DINP is a plasticizer that is most commonly added to a covering material for an insulated wire used in an automobile wire harness.

  The water stop agent 40 is comprised from the composition of an ultraviolet curable resin. The present invention has a great feature in that a plasticizer of the same kind as the plasticizer of the covering material 3 of the insulated wire is added to the waterstop agent. The plasticizer of the covering material 3 added to the water-stopping agent 40 and the “same type” plasticizer mean the same type of plasticizer, and may be in a range classified by the above-described plasticizer. . For example, when the plasticizer of the coating material is DINP, the phthalate ester plasticizer can be said to be the same kind of plasticizer. The same kind of plasticizer is more preferably the same plasticizer.

  If the same kind of plasticizer as the plasticizer of the covering material 3 is preliminarily contained in the waterproofing agent 40, when the waterproofing portion 10 of the wire harness is exposed to a high temperature state, the waterproofing portion is removed from the covering material 3. The amount of plasticizer transferred to 40 can be suppressed. The amount of the plasticizer contained in the water-stopping agent 40 is preferably the same amount as the amount of plasticizer transferred from the coating material 3 to the water-stopping agent 40 and saturated.

  The content of the plasticizer added to the water stopping agent 40 is preferably in the range of 5 to 15% by mass in the water stopping agent 40. In general, the amount of plasticizer transferred from the insulator to the water-stopping agent reaches a maximum (about 18%) and saturates at 120 ° C. for about 120 hours (5 days). When the heating state is further continued, the transferred plasticizer volatilizes and the transfer amount is reduced to about 15%. Here, the migration amount and the volatilization amount are in an equilibrium state, and the content of the plasticizer in the waterstop agent is maintained at about 15% by mass. Moreover, when the plasticizer in the water-stopping agent 40 is increased, the physical properties are significantly lowered. For this reason, the upper limit of the plasticizer content is preferably 15% by mass. Further, the lower limit of the plasticizer content is that if the plasticizer content in the water-stopping agent 40 is too small, the effect of preventing migration may not be sufficiently obtained, so the plasticizer content is 5% by mass. The above is preferable.

  When a plasticizer is added to the water-stopping agent 40 in advance, the peel adhesion strength between the water-stopping agent 40 and the covering material 3 is lower in the initial stage (the state immediately after the production) than when no plasticizer is added. However, the peel adhesion strength after heating to high temperature (after heating) shows a significant decrease in the adhesion strength of the water-stopping agent to which no plasticizer has been added, whereas the adhesion of the water-stopping agent 40 to which a plasticizer has been added. The decrease in strength is reduced, and finally the adhesive strength of the water stop agent 40 to which a plasticizer is added is increased.

  The degree of adhesive strength between the water-stopping agent 40 and the covering material 3 may be 500 N / m or more in terms of the peel adhesive strength between the water-stopping agent 40 and the covering material 3 after the wire harness is heated at 120 ° C. for 120 hours. In this case, the water stopping performance of the water stopping portion is sufficiently obtained. It has been found that even when the test is conducted with the heating time exceeding 120 hours, the peel adhesion strength does not change any more.

  The peel adhesion strength between the water-stopping agent and the coating material is determined by a T peel test according to JIS-K6854 using a test piece in which the vinyl chloride resin of the coating material is bonded to the curable resin composition of the water-stopping agent. Is.

  The conductor 2 of the insulated wire 4 is a single wire or a stranded wire of a wire such as copper, a copper alloy, or aluminum.

  The intermediate splice part 20 is obtained by partially removing the covering material 3 at the intermediate part in the longitudinal direction of the insulated wire 4 to expose the conductor 2 and joining the conductor 2 of another insulated wire 4 to the conductor 2. The conductor 2 of the other insulated wire 4 may be exposed at the intermediate portion in the longitudinal direction of the insulated wire 4 or may be exposed at the end of the insulated wire 4. . Here, the latter example will be described. Moreover, in the wire harness 1, the insulated wire 4 is not limited to four, What is necessary is just two or more, and the number of the insulated wires 4 is not specifically limited.

  In the intermediate splice portion 20, the conductors 2 can be joined to each other by means such as welding by resistance welding, ultrasonic welding, laser welding, or the like. The conductor 2 in the splice part 20 may be joined by a method in which a component such as an intermediate crimp terminal is crimped to the joint part.

  As the water stop agent 40, a composition is used in which a plasticizer of the same type as the plasticizer of the covering material 3 of the insulated wire is added to an ultraviolet curable resin. The ultraviolet curable resin contains a polymerizable compound, a photopolymerization initiator, a thermal radical polymerization initiator, and the like.

  As the polymerizable compound, a combination of an acrylate compound such as a chain acrylate monomer and a cyclic acrylate monomer, and a cyclic N-vinyl monomer can be used. As the acrylate compound, a urethane acrylate oligomer and an acrylate monomer are combined. Things.

  As the urethane acrylate oligomer, urethane acrylate obtained by reacting bisphenol A / ethylene oxide addition diol, tolylene diisocyanate and hydroxyethyl acrylate; urethane obtained by reacting polytetramethylene glycol, tolylene diisocyanate and hydroxyethyl acrylate Acrylate: Urethane acrylate obtained by reacting tolylene diisocyanate and hydroxyethyl acrylate. These oligomers may be used alone or in combination of two or more.

  Examples of the acrylate monomer include a chain acrylate monomer and a cyclic acrylate monomer. The cyclic acrylate monomer is an acrylate monomer having a cyclic structure such as an alicyclic ring or an aromatic ring. Examples of the cyclic acrylate monomer include isobornyl (meth) acrylate, bornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tricyclodecanyl (meth) acrylate, and dicyclohexane. Examples include alicyclic structure-containing (meth) acrylates such as pentanyl (meth) acrylate; benzyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, and acryloylmorpholine. As the cyclic acrylate monomer, isobornyl (meth) acrylate is preferable. As the cyclic acrylate monomer, IBXA (trade name of Osaka Organic Industrial Chemical Co., Ltd.), Aronix M-111, M-113, M-114, M-117, TO-1210 (trade name of Toa Gosei Co., Ltd.) Can be used. In this specification, the chain acrylate monomer is a linear or branched acrylate monomer that does not contain a cyclic structure. Examples of chain acrylate monomers include neopentyl glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, and 2-butyl-2ethyl-1,3-propanediol. Diacrylate, 2,4-diethyl-1,5-pentanediol diacrylate, 2-methyl-1,8-octanediol diacrylate, 1,9-nonanediol diacrylate, phenoxyhexaethylene glycol acetate, hydroxypivalate neo Pentyl glycol acrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, trimethylolpropane triacrylate, EO-modified trimethylolpropane triacrylate, dipentaerythritol Lumpur hexaacrylate, and the like.

  A methacrylate compound may be used together with the acrylate compound. Examples of the methacrylate compound include di-2-methacryloxyethyl phosphate, mono [2- (meth) acryloyloxyethyl] phosphate, mono [2- (meth) acryloyloxyethyl] diphenyl phosphate, and mono [2- (meta ) Acryloyloxyethyl] phosphate, bis [2- (meth) acryloyloxypropyl] phosphate, tris [2- (meth) acryloyloxyethyl] phosphate, and O = P (-R1) in JP-A-11-100414 -R2) (-R3) and the like.

  The said cyclic N-vinyl monomer is a vinyl monomer which has cyclic structures, such as an aromatic ring and an alicyclic ring, and contains a nitrogen atom. Examples of the cyclic N-vinyl monomer include N-vinyl pyrrolidone, N-vinyl caprolactam, vinyl imidazole, vinyl pyridine and the like.

  Examples of the photopolymerization initiator include benzophenone derivatives such as benzophenone, methyl orthobenzoin benzoate, 4-benzoyl-4′-methyldiphenyl sulfide, thioxanthone and derivatives thereof, 2-methyl-1- [4- (methylthio). ) Phenyl] -2-morpholino-propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoin derivative, benzyldimethyl ketal, α-hydroxyalkylphenone, α-aminoalkylphenone, acylphosphine oxide, Examples include monoacylphosphine oxide, bisacylphosphine oxide, acrylphenylglyoxylate, diethoxyacetophenone, and titanocene compounds. The photopolymerization initiator can be appropriately selected in consideration of the curing speed, yellowing and the like. A photoinitiator may be used independently and may be used in combination of 2 or more type.

  Specific combinations of photopolymerization initiators include, for example, Lucillin TPO (trade name of BASF Japan) and Irgacure 184 (manufactured by Ciba Specialty Chemicals), Lucirin TPO (trade name of BASF Japan) and Irgacure 651. (Trade name of Ciba Specialty Chemicals), Lucyrin TPO (trade name of BASF Japan) and Irgacure 907 (trade name of Ciba Specialty Chemicals), Irgacure 184 and Irgacure 907 (both are Ciba Specialty Chemicals) Product name).

  The content of the photopolymerization initiator in the composition liquid is preferably in the range of 0.1 to 5% by mass, more preferably in the range of 0.3 to 2% by mass. If the content of the photopolymerization initiator is reduced and it is less than 0.1% by mass, it may not be photocured even at a location where it is sufficiently exposed to light. When it exceeds, many unreacted photoinitiators will remain easily. The remaining photopolymerization initiator is activated by heat, light, and the like, discolors the sealed portion after curing, and may cause physical properties such as an increase in Young's modulus and a decrease in elongation due to the reaction.

  Examples of the thermal radical polymerization initiator include azoisobutyl nitrile (AIBN), benzoyl peroxide (BPO), lauroyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide, cumene hydroperoxide, di-tert-butyl peroxide, tert -Peracid compounds such as butyl perbenzoate and cyclohexanone peroxide.

  In addition to the polymerizable compound, photopolymerization initiator, and thermal radical polymerization initiator, other additives may be added to the curable resin composition. Examples of such additives include antioxidants, coloring materials, ultraviolet absorbers, light stabilizers, silane or titanium-based coupling agents, antifoaming materials, curing accelerators, thiol compounds, phosphate esters, and the like. Adhesive aids, leveling agents, surfactants, storage stabilizers, polymerization inhibitors, plasticizers, lubricants, fillers, anti-aging agents, wettability improvers, coating film improvers, and the like.

  When the ultraviolet curable resin composition is heated, it penetrates into the intermediate splice part 20, and the gap between the insulators 3 of the insulated wire 4, between the strands constituting the conductor 2, between the conductors 2, etc. It has fluidity that can fill the gap.

  In the ultraviolet curable resin composition, the cured product is preferably flexible and has an appropriate rubber elasticity. As specific physical properties of the cured product, the elongation of the cured product is preferably 50% or more at room temperature, and more preferably 100% or more. The cured product preferably has a low temperature (−50 ° C.) elongation of 10% or more, and more preferably 20% or more. When the cured product is flexible and has an appropriate rubber elasticity, it is difficult to cause damage such as cracks and breaks when the water-stopping portion 10 is subjected to a cold heat cycle, an external tensile force, a bending stress, or the like. The measurement of the elongation at break (%) of the cured product was carried out using a tensile tester (AGS, manufactured by Shimadzu Corporation) using a film in which a curable resin composition was formed to a thickness of 200 μm in accordance with JIS-K7113. It can be measured by doing.

  The protective sheet 30 covers the surface of the water-stopping agent 40 in a state of being in close contact with the surface of the water-stopping agent 40. The protective sheet 30 has transparency to irradiation light such as ultraviolet rays when the curable resin composition of the water blocking agent 40 is cured. The light transmittance of the protective sheet 30 is preferably, for example, an ultraviolet transmittance of 50% or more, and more preferably an ultraviolet transmittance of 90% or more. The thickness of the protective sheet 30 is preferably 100 μm or less, more preferably 5 to 50 μm.

  As the protective sheet 30, a wrap sheet of olefin resin such as polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, and polyvinylidene fluoride, or a wrap sheet of general-purpose resin such as polyester, polyethylene terephthalate, and nylon can be used. . The protective sheet 30 is preferably a sheet of polyvinyl chloride resin, polyvinylidene chloride resin, or polyvinylidene fluoride resin that has particularly good self-adhesion (adhesion).

  The protective sheet 30 has a Young's modulus (value at room temperature in the measurement direction according to JIS-K7113) in the range of 50 to 500 MPa when the thickness is less than 50 μm, and 10 to 100 MPa when the thickness is 50 μm to 100 μm. When the thickness exceeds 100 μm, it is preferably less than 10 MPa. Further, the protective sheet 30 has an elongation at break of preferably 20% or more, more preferably 50% or more.

  The protective sheet 30 preferably has a self-adhesion strength in a range of 0.5 to 10 N / m expressed by peel adhesive strength (value at room temperature in a measurement method according to JIS-Z0237 or JIS-K6854). The water-stopping part 10 follows the deformation of the surface of the water-stopping agent 40, the protective sheet 30 is deformed, and the water-stopping agent 40 is cured in a state where the surface of the water-stopping agent 40 and the protective sheet 30 are in close contact with each other. . When the protective sheet 30 has a high self-adhesive force, when the protective sheet 30 is wound around the intermediate splice portion 20 and the water-stopping agent 40, the protective sheet 30 is easily covered and has excellent workability.

  Further, a pressure-sensitive adhesive layer made of a weak pressure-sensitive adhesive having a thickness of 10 μm or less may be formed on the surface of the protective sheet 30. The thickness of the pressure-sensitive adhesive layer is preferably 5 μm or less.

  Hereinafter, the manufacturing method of the wire harness of FIG. 1 will be described. 3A to 3C show an example of the manufacturing process of the wire harness of the present invention, and are explanatory diagrams in the vicinity of the water stop middle splice. As shown in FIG. 3A, first, a wire bundle 7 in which an intermediate splice portion 20 is formed in advance using a plurality of insulated wires is prepared. The wire bundle 7 has a conductor exposed portion 5 where the insulator 3 of the insulated wire 4 is removed and the internal conductor 3 is exposed.

  Then, as shown in FIG. 3A, a protective sheet 30 large enough to cover the intermediate splice portion 20 is prepared, and the intermediate splice portion 20 of the wire bundle 5 is placed on the protective sheet. Next, a water-stopping agent is supplied onto the intermediate splice unit 20. The water stopping agent 40 is discharged and supplied from the nozzle 60 of the discharge device by a predetermined amount. The water-stopper is supplied at room temperature. In addition, after supplying the water stop agent 40 to the protection sheet 30, you may make it mount an electric wire bundle on a water stop agent.

  Next, as shown in FIG. 3B, the folded back side of the protective sheet 30 is wound around the intermediate splice part 20 and the water stopping agent 40, and the protective sheets 30 overlap each other in a portion without the intermediate splice part 20. Bend to be part 32. The overlapping portion 32 of the protective sheet 30 is maintained in an overlapped state by the self-adhesiveness of the protective sheet 30.

  Next, the protective sheet 30 is wound around the surface of the water-stopping agent 40 of the intermediate splice unit 20 so that the water-stopping agent 40 is filled in the protective sheet 30. After the protective sheet 30 is folded in half, the overlapping portion of the protective sheet 30 is rubbed with the roll 51, and the water stopping agent 40 of the overlapping portion 32 is pushed toward the intermediate splice portion 20. The overlapping portion 32 of the protective sheet 30 is wound around the water stop portion 10 to be in close contact therewith.

  Next, as shown in FIG. 3C, the overlapping portion of the protective sheet 30 is wound around the intermediate splice portion 20 and the waterstop agent 40. When the protective sheet 30 is pulled and wound in a state where tension is applied, the protective sheet 30 is wound around the intermediate splice part 20 and the waterproofing agent 40 in a state where the waterproof part 10 is pressed from the outside of the protective sheet 30.

  As a result, the water-stopping agent 40 that was locally present around the intermediate splice part 20 is extruded and travels between the outer peripheral part of the intermediate splice part 20 and the protective sheet 30, and the outer periphery of the intermediate splice part 20. Covering the whole. The protection sheet 30 is maintained in a state of being wound around the water stop portion 10 by self-adhesion. Further, the water stop portion 10 is also maintained in a state where it is pressed from the outside of the protective sheet 30.

  Next, as shown in FIG. 3 (c), the intermediate splice unit 20 is wound around the outer periphery of the intermediate splice unit 20 and the water-stopping agent 40 using the ultraviolet irradiation device 52. The surface of the water-stopping agent 40 is cured by irradiating with ultraviolet rays 53 to form a surface layer portion.

  The ultraviolet rays 53 irradiated to the intermediate splice part 20 pass through the protective sheet 30 and are irradiated to the water stop agent 40. At this time, the ultraviolet irradiation is performed under irradiation conditions such that only the surface of the ultraviolet curable resin composition of the water-stopping agent 40 is cured. Since the surface of the water stopping agent 40 in contact with the protective sheet 30 is cured, the water stopping agent 40 can be prevented from flowing out from the end 33 of the protective sheet 30 to the outside.

  As the ultraviolet irradiation device, a light source such as a bulb-type UV lamp or an LED-UV lamp in which Hg, Hg / Xe, a metal halide compound or the like is enclosed can be used. Further, the ultraviolet irradiation device may use a condensing UV irradiation device that collects and irradiates light from the light source with a reflection mirror.

  Further, using a heating device or the like, the intermediate splice portion 20 is heated, the water-stopping agent 40 is heated to a temperature of about 80 ° C. to reduce the viscosity, and the gap between the strands of the conductor 3 or the gap between the wires is increased After penetrating and filling, the water-stopping agent 40 may be further heated to be completely thermoset at about 140 to 150 ° C. Examples of the heating device 70 include a ceramic heater, a hot air jet heater, a pipe electromagnetic heater, a halogen lamp heater, and a contact rubber heater.

  In the above method, the UV curable resin is cured in two steps by curing the surface layer by ultraviolet irradiation and then curing the inner layer by heating, but after infiltrating the UV curable resin. The entire water-stopping agent may be cured by only one ultraviolet irradiation.

  4 (a) to 4 (e) show manufacturing steps of another example of the method for manufacturing the wire harness of the present invention, and are explanatory diagrams in the vicinity of the water stop intermediate splice portion. As a method of winding the protective sheet 30 around the intermediate splice part 20, as shown in FIG. 4A, a winding device using a pair of rollers 110 arranged so as to contact each other can be used. In the winding device, when the electric wires at both ends of the intermediate splice portion 20 are moved downward along the pair of side grooves, the intermediate splice portion 20 is sandwiched between the pair of rollers 110, and the pair of rollers The roller 110 is moved downward while rotating. Hereinafter, a winding method using this winding apparatus will be described.

  First, as shown in FIG. 4A, the protective sheet 30 is placed on the top plate portion, the water stopping agent 40 is supplied onto the protective sheet 30, and the intermediate splice portion 20 is placed.

  Next, as shown in FIG. 4B, the wire bundle is moved downward along the lateral groove. The intermediate splice part 20 is sandwiched between the pair of rollers 110 while being sandwiched by the protective sheet 30. The pair of roller parts 110 sandwich the intermediate splice part 20, the water stopping agent 40 and the protective sheet 30 while elastically deforming according to the shape of the peripheral part of the intermediate splice part 20. Thereby, as shown in FIG.4 (c), the protective sheet 30 is wound around the intermediate splice part 20 and the water stop agent 40, applying force from the circumference.

  Next, as shown in FIG. 4D, the rod-shaped member 120 is moved toward the intermediate splice portion 20 with the intermediate splice portion 20 sandwiched between the pair of rod-shaped members 120. As shown in FIG. 4E, the protection sheet 30 is wound around the surface of the water stopping agent 40 in a state where the water stopping portion is pressed from the outside of the protection sheet 30.

  Examples of the present invention and comparative examples are shown below. The present invention is not limited to the examples.

Example 1
[Water stop middle splice part]
An intermediate splice work having a 4.4φ polyvinyl chloride (PVC) -coated electric wire as a main line and two 3.6φ PVC-coated electric wires as branch lines was produced. As the main line and branch line PVC electric wires, those having a covering material containing 18% by mass of DINP as a plasticizer were used in PVC.

[UV curable resin composition of water-stopper]
The UV curable resin composition containing the following urethane acrylate having a viscosity of 20 Pa · s (25 ° C.) containing DINP as a plasticizer so as to be 10% by mass in the composition. A resin composition was obtained. The ultraviolet curable resin before addition of the plasticizer had a Young's modulus after curing of 5 MPa, and the Young's modulus after curing of the ultraviolet curable resin after addition of the plasticizer was 1 MPa.

(Composition of urethane acrylate)
-60 parts by mass of urethane acrylate oligomer-40 parts by mass of acrylate monomer

[Filling with waterproofing agent]
A transparent PVC wrap film with a UV transmittance of 94% is used as a protective sheet, 1.1 g of the water-stop agent is applied to the center of the wrap film, and the intermediate splice part of the intermediate splice work is placed on the PVC. The wrap film was pasted together and narrowed down, and the pasted PVC wrap film was rolled up to cover the intermediate splice and the surface of the covering material about 16 mm long.

[Curing water-stopper]
Next, using a LED irradiator (LED-UV lamp) having a central wavelength of 385 nm, the water-stopping agent wound with the PVC wrap film was irradiated with ultraviolet rays and cured to produce the wire harness of Example 1. .

Comparative Example 1
For comparison, except that the plasticizer was not added to the ultraviolet curable resin of Example 1, the same material as in Example 1 was used, the same treatment was performed to form a water stop portion, and Comparative Example 1 wire harness was produced.

  About the obtained wire harness, about the initial stage and after putting the whole water stop part into a 120 degreeC thermostat for 120 hours (after a heating), the pressure resistance test and the test of peeling adhesive strength were done.

[Evaluation of water stoppage performance by pressure test]
In the pressure resistance test, an air pressure of 200 kPa was applied from all the electric wires at both ends of the harness for 1 minute in a state where the entire water stop middle splice was immersed in water, and the presence or absence of air leak was observed. As a result, in the initial stage, both Example 1 and Comparative Example 1 were in a good airtight state with no air leak. Example 1 had a pressure and air tightness of 200 kPa even after heating. On the other hand, in Comparative Example 1, occurrence of air leak was observed from both the electric wire and the water-stopping agent and between the coating material and the water-stopping agent at 50 kPa and 30 seconds.

  When the state of the water-stopping agent (ultraviolet curable resin) after heating in Comparative Example 1 was observed, softening of the resin was observed. Moreover, when the plasticizer in the ultraviolet curable resin after the heating of the comparative example 1 was analyzed, 18 mass% of plasticizers (DINP) were contained.

[Measurement of peel adhesion strength]
The peel adhesion strength is determined by bending and pulling the two wires of 4.4mm and 3.6φ wires in the water stop intermediate splice part into a T shape, and the peel bond strength between the coating material and the water stop agent. It was measured. Specifically, the value obtained by dividing the stress when the electric wire was peeled off from the water-stopping agent by the total length of the electric wire adhesion semicircle was taken as the adhesive strength. As a result of the measurement, the initial peel adhesive strength of Comparative Example 1 was 3500 N / m, but the peel adhesive strength after 120 hours at 120 ° C. was reduced to 400 N / m. On the other hand, Example 1 had an initial peel adhesive strength of 1000 N / m, and the initial value was lower than that of Comparative Example 1, but the adhesive strength after heating was 800 N / m. Compared to Example 1, it had twice the peel adhesion strength.

  The present invention is not limited to the above embodiments. In the said Example, although the electric wire bundle in which four electric wires were bundled in the intermediate splice part was demonstrated as an example, the electric wire bundle should just be a some electric wire and may use electric wires other than four.

  In the above embodiment, an example in which the water-stopping portion is applied to the intermediate splice portion has been described. However, the present invention provides a water-stopping device for a terminal splice obtained by filling a light-permeable protective cap with a water-stopping agent. It can be applied to a water stop portion of a ground terminal constituted by a portion, a crimp terminal, a water stop portion of a wire crimping terminal for inserting a connector, or the like.

DESCRIPTION OF SYMBOLS 1 Wire harness 2 Conductor 3 Coating | covering material 4 Insulated electric wire 5 Conductor exposure part 6 Front and back coating part adjacent to conductor exposure part 7 Wire bundle 10 Water stop middle splice part (water stop part)
20 Intermediate splice part 30 Protective sheet 40 Water stop agent

Claims (5)

A conductor exposed portion having an electric wire bundle in which a plurality of insulated electric wires whose conductors are covered with a covering material made of an insulating material is bundled, in which a part of the covering material is removed and an internal conductor is exposed is an ultraviolet curable resin A wire harness having a water stop portion that is covered with a water stop agent, and the surface of the water stop agent is covered with a light-transmitting protective sheet,
A wire harness, wherein a plasticizer of the same type as the plasticizer contained in the wire covering material is added to the waterstop agent.   The wire harness according to claim 1, wherein the content of the plasticizer added to the water-stopping agent is within a range of 5 to 15% by mass in the water-stopping agent.   The wire harness according to claim 1, wherein the water stopping agent of the water stopping portion covers a surface of the covering material adjacent to the conductor exposed portion.   2. The wire harness according to claim 1, wherein the adhesive strength between the water-stop agent and the coating material is 500 N / m or more as a peel adhesive strength after 120 hours of treatment at 120 ° C. 3. A conductor exposed portion having an electric wire bundle in which a plurality of insulated electric wires whose conductors are covered with a covering material made of an insulating material is bundled, in which a part of the covering material is removed and an internal conductor is exposed is an ultraviolet curable resin A wire harness manufacturing method having a water stop portion coated with a water stop agent, wherein the surface of the water stop agent is covered with a light-transmitting protective sheet,
Using a water-stopping agent to which a plasticizer of the same type as the plasticizer contained in the covering material is added, supplying the water-stopping agent to the water-stopping portion, and using a protective sheet having light permeability, A method of manufacturing a wire harness, wherein the surface is covered and light irradiation is performed to cure the water-stopping agent.

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