JP2009202345A - Die for electric wire extruder and manufacturing method of electric wire using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, in manufacturing an ordinary electric wire, when the adhesion between the insulator layer composing the coating part and the conductor composing the wire material becomes high, the workability of removing the insulator layer falls, for example, in the case where the insulator layer of the end part of the electric wire is stripped off to expose the wire material and the connection terminal is pressure-bonded to this part and in like cases. <P>SOLUTION: The die 11 for the electric wire extruder includes the extrusion die 12 having a flow passage for a thermoplastic resin member and the extrusion nipple 13 which is concentrically arranged in the flow passage and inserts/passes a wire material to be coated. The flow passage of the extrusion die includes a first flow passage section 16 which reduces its diameter in a tapered shape from the inlet section and a second flow passage section 17 of a predetermined diameter which communicates with this. The opening angle of the first flow passage section is set to be 20°to 35°, and the inner diameter of the second flow passage section is set to be 1-1.5 times of the outer diameter of the product and the length is set to be >0 and <3 mm. The extrusion nipple has a tapered section 13b the diameter of which contracts in a tapered shape from the inlet side of the flow passage, and the opening angle of the tapered section is set to be 20° to 30°. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a die for an electric wire extruder used for extrusion of an electric wire used for, for example, an automobile wire harness, and a method of manufacturing an electric wire using the same.

  Due to environmental problems in recent years, thermoplastic resin members composed of halogen-free olefin-based resins and metal hydroxides from PVC (polyvinyl chloride) members are used as the insulation material for automobile wires that constitute wire harnesses. It's getting on. When a conventional PVC member was used for the wire covering material, the generation of resin residue called so-called “Meani” was not observed, but when the above thermoplastic resin material was extruded as an insulating material for automobile wires, the characteristics of the material As a result, it becomes easy to generate a crack during extrusion molding.

  And when the generated mayani adheres to the surface of the cable covered, there is a problem that not only the appearance of the cable is impaired, but also the workability of the wire harness becomes extremely difficult.

  In order to solve such a problem, the radius of curvature is 0.1 mm or more at the outlet portion 2 of the hole portion 4 forming the flow path F of the thermoplastic resin member melted in the die 1 for the extruder as shown in FIG. A trumpet-shaped first curved wall (R portion) 5 that is less than 10 mm is formed, and a trumpet-shaped second curved wall (R portion) 8 that has a radius of curvature of 0.1 mm or more at the die entrance portion 6. An extruder die has been known in which the removal process of the spears is reduced by forming the cable and a product having no scratch on the cable surface is formed (for example, see Patent Document 1).

  However, the extruder die 1 having the above structure increases the cost because the first and second curved portions (R portions) 5 and 8 are manufactured at the inlet portion and the outlet portion of the flow path of the thermoplastic resin member. There was a problem.

And in order to solve such a problem, the metal mold | die for electric wire extruders as described in patent document 2 was proposed. This mold for an electric wire extruder includes an extrusion die having a flow path of a thermoplastic resin member, and an extrusion nipple that is concentrically arranged in the flow path and inserts a wire to be covered, and is formed by extrusion molding. The wire is covered with a thermoplastic resin member. The flow path of the extrusion die has a first flow path portion that is tapered from the inlet portion and a second flow path portion having a predetermined diameter that communicates with the first flow path. The opening angle of the path part is 25 to 35 degrees, the inner diameter of the second flow path part is 1 to 2 times the outer diameter of the electric wire, the length of the second flow path part is 3 mm to 4 mm, and the nipple for extrusion is And a tapered portion having a tapered diameter from the inlet side of the flow path, and a cylindrical portion having a predetermined diameter connected to the tapered portion, and the opening angle of the tapered portion is 10 degrees to 20 degrees. The length is 4 mm to 5 mm, and the outlet end face of the second flow path portion of the extrusion die and the outlet end face of the cylindrical portion of the extrusion nipple are flush with each other.
Japanese Patent Laid-Open No. 11-34141 (page 3, FIG. 1) JP 2007-196498 A (page 3-4, FIG. 1)

  The die for an electric wire extruder described in Patent Literature 2 is very excellent in solving the disadvantages of the die for an electric wire extruder described in Patent Literature 1, and particularly for the production of a shielded electric wire. Appropriateness is demonstrated in the examples in the document.

  On the other hand, unlike a shielded electric wire, with respect to a normal electric wire used for an automobile wire harness, when the adhesion between the insulator layer constituting the covering portion and the conductor constituting the wire becomes high, for example, insulation of the end portion of the electric wire When the body layer is peeled to expose the wire and the connection terminal is crimped to this portion, there arises a problem that the workability of removing the insulator layer is lowered, and there is a first request to solve this problem. .

  In addition, when the material constituting the insulator layer is an olefin resin and a metal hydroxide, there is a problem of the occurrence of the above-mentioned meander. There were two requests.

  The objective of this invention is providing the metal mold | die for electric wire extruders which can satisfy | fill the request | requirement mentioned above simultaneously in manufacturing a normal electric wire, and the manufacturing method of an electric wire using the same.

In order to solve the above-described problem, a die for an electric wire extruder according to claim 1 of the present invention is provided.
An extrusion die having a flow path for a thermoplastic resin member; and an extrusion nipple that is concentrically disposed in the flow path and through which a wire material to be coated is inserted, and is formed by extrusion molding with the thermoplastic resin member. In the mold for the extruder of the wire to be coated,
The flow path of the extrusion die has a first flow path portion that is tapered from the inlet portion and a second flow path portion having a predetermined diameter that communicates with the reduced diameter portion of the first flow path portion. The opening angle of the first flow path part is 20 to 35 degrees, the inner diameter of the second flow path part is 1 to 1.5 times the outer diameter of the electric wire, and the length of the second flow path part is 0. And less than 3mm,
The extrusion nipple has a taper portion whose diameter decreases in a taper shape from the inlet side of the flow path, and an opening angle of the taper portion is 20 degrees to 30 degrees.

Moreover, the manufacturing method of the electric wire concerning Claim 2 of this invention is as follows.
An extrusion die having a flow path for a thermoplastic resin member; and an extrusion nipple that is concentrically disposed in the flow path and through which a wire material to be coated is inserted, and is formed by extrusion molding with the thermoplastic resin member. A thermoplastic resin member composed of an olefin resin and a metal hydroxide is continuously poured into the mold for the extruder of the electric wire to be coated from the inlet portion of the first flow path portion, and the wire material is A method of manufacturing an electric wire by manufacturing an electric wire made of a wire covered with the thermoplastic resin member by continuously inserting from the expanded diameter portion of the nipple for extrusion,
The flow path of the extrusion die has a first flow path portion that is tapered from the inlet portion in a tapered shape, and a second flow path portion having a predetermined diameter that communicates with the reduced diameter portion of the first flow path. The opening angle of the first flow path part is 20 to 35 degrees, the inner diameter of the second flow path part is 1 to 1.5 times the outer diameter of the electric wire, and the length of the first flow path part is 0. The extrusion nipple has a taper portion that is tapered from the inlet side of the flow path, and the opening angle of the taper portion is 20 degrees to 30 degrees. It is characterized by being.

  For example, when the adhesion between the insulator layer constituting the covering portion and the conductor constituting the wire rod is increased with respect to a normal electric wire used in an automobile wire harness, for example, the insulator layer at the end of the wire is peeled off to expose the wire rod. Then, the problem that the workability of removing the insulator layer is lowered when the connection terminal is crimped to this portion is described in claim 2 of the present invention and the mold for an electric wire extruder according to claim 1 of the present invention. This can be solved by the method of manufacturing the electric wire.

  Further, when the material constituting the insulator layer is an olefin-based resin and a metal hydroxide, there is a problem of the occurrence of the above-mentioned scumming, but the wire mold for the electric wire extruder according to claim 1 of the present invention and the present invention According to the method for manufacturing an electric wire according to the second aspect, the amount of occurrence of this mean can be reduced as much as possible even in the process of manufacturing an ordinary electric wire.

  According to the present invention, for example, in manufacturing a normal electric wire used for an automobile wire harness, when the adhesion between the insulator layer constituting the covering portion and the conductor constituting the wire becomes high, for example, at the end of the electric wire. It was possible to solve the problem that the workability of removing the insulating layer was lowered when the insulating layer was peeled off to expose the wire and the connecting terminal was crimped to this portion.

  Further, when the material constituting the insulator layer is an olefin resin and a metal hydroxide, there is a problem of the occurrence of the above-mentioned scum. According to the present invention, this sag generation is reduced as much as possible in the process of manufacturing a normal electric wire. I was able to reduce it.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cross section of an extruder die 11 for an electric wire according to the present invention. The extruder die 11 includes an extrusion die 12 and an extrusion nipple (mandrel) 13. The extrusion die 12 has a cylindrical shape, and a flow path 15 of a thermoplastic resin member melted from one end (inlet side) end surface 12a to the other side (outlet side) end surface 12b is formed through the center.

  The flow path 15 includes an inlet-side flow path section (first flow path section) 16 and an outlet-side flow path section (second flow path section) 17, and the flow path section 16 extends from the inlet section 16 a to the flow path section. The inner wall surface 16 b is formed in a tapered shape with a predetermined opening angle α up to the communicating portion with 17. The flow path part 17 has a predetermined inner diameter A, and the outlet part 17b opens to the end face 12b. And this flow-path part 17 is set to predetermined length from the end surface 12b of the exit part 17b.

  The extrusion nipple 13 is arranged concentrically with an annular space at the center of the flow path 15. The tip portion 13a of the extrusion nipple 13 has a shape substantially corresponding to the shape of the first flow path portion 16 of the flow path 15 of the extrusion die 12, and is tapered from the end face 12a side of the extrusion die 12. It consists of a tapered portion 13b that is reduced in diameter and faces the inner wall surface 16b of the flow path portion 16.

  The end surface 13e of the outlet portion 13d of the taper portion 13b is positioned slightly retracted into the channel portion 17 from the end surface of the outlet portion 17b of the channel portion 17, that is, the end surface 12b of the extrusion die 12. Further, the outer peripheral surface 13f of the tapered portion 13b is set to a predetermined opening angle β (that is, an angle of a D portion in an embodiment described later).

  The inner diameter of the flow path portion 17 that is the outlet diameter (that is, the inner diameter of the A portion in the embodiments described later) is 1 to 1.5 times larger than the outer diameter of the electric wire as a product, but preferably 1 times is good. Further, the length of the flow path portion 17 (that is, the length of the B portion forming a land in an embodiment described later) is 3 mm or less, preferably 2 mm or less. Further, the opening angle α of the inner wall surface 16b of the flow path portion 16 (that is, the angle of the C portion in the embodiment described later) is 20 degrees to 35 degrees, preferably 20 degrees to 30 degrees. good. Further, the opening angle β of the outer peripheral surface 13f of the taper portion 13b of the extrusion nipple 13 (that is, the angle of the D portion in the embodiment described later) is 20 degrees to 30 degrees.

  Next, a method for producing an electric wire using the extruder die 11 having the above-described structure will be described. First, an extruder die 11 having the above-described structure is prepared, and then a wire to be coated (not shown) is placed in the extrusion nipple 13 from the inlet side of the taper portion 13b by using a wire conveying / inserting machine (not shown) with an arrow X. It is inserted as shown and extruded from the outlet side of the taper portion 13b, and at the same time, a thermoplastic resin member composed of an olefin resin and a metal hydroxide is melted and indicated by an arrow Y from the inlet portion of the flow path 15. In this manner, the wire is continuously supplied so that the periphery of the wire is surrounded by the thermoplastic resin, and an electric wire made of the wire covered with the thermoplastic resin member is manufactured.

  Then, since the evaluation test which supports the usefulness of the metal mold | die for electric wire extruders which concerns on this invention, and the manufacturing method of an electric wire using the same was done, this is demonstrated as an Example below. In this evaluation test, the electric wire was actually manufactured by extrusion, and a five-stage evaluation was performed on the state after the production of 10,000 m of the electric wire.

  As for the evaluation score, the amount of occurrence of the sea cucumber was evaluated in 5 stages, with 1 being a small amount and 5 being a large amount. Further, the adhesion strength representing the peel strength between the insulator layer and the conductor was evaluated in five stages, with 1 being small (appropriate) and 5 being large (inappropriate).

In the following examples, a 10,000 m long electric wire actually obtained by extrusion manufacturing of the electric wire is referred to as “product”, the exit portion of the extrusion die is referred to as A portion, and the land of the extrusion die is referred to as “product”. A description will be given assuming that the first flow path portion that is reduced in diameter from the inlet portion of the flow path of the extrusion die is referred to as C section, and the extrusion nipple is referred to as D section.
Example 1
In the present Example 1, as Example 1, five different magnifications (specifically, 1 ×, the magnification with respect to the product outer diameter of the inner diameter of the A portion which is the exit portion of the extrusion die with respect to the product outer diameter after manufacture) 1.5 times, 2 times, 3 times, and 4 times), and the amount of generation and adhesion (peeling strength between the insulator layer and the conductor) corresponding to each magnification were measured and given evaluation points. In addition, the evaluation test was not performed about the case where magnification is smaller than 1 time here. This is because if the magnification is smaller than 1, the resin pressure increases, which may cause disconnection during the manufacture of the electric wire. The evaluation test results of Example 1 are shown in Table 1 below.

上記評価試験結果により、押出用ダイの出口径Ａを電線外径の１〜１.５倍にすると、評価試験の合計点数が２点又は３点となり、絶縁体層と導体との剥離強度（以下「密着力」という）を低下させると共に、メヤニ発生量も低下させることが分かった。この場合、倍率が１倍の方が合計点数が２点となり、メヤニ発生量がさらに少なくなり、より好ましいことが分かった。
（実施例２）
本実施例２においては、製造後の電線（製品）外径に対するランドであるＢ部の長さ（ｍｍ）を異なる５つの長さ（具体的には、１ｍｍ、２ｍｍ、３ｍｍ、４ｍｍ、５ｍｍ）とし、この各倍率に対応するメヤニ発生量及び密着力（絶縁体層と導体の剥離強度）をそれぞれ測定して上述の実施例と同様の５段階評価の評価点をつけた。なお、１ｍｍより短い長さについて評価試験を行わなかった。この理由は、この長さを０ｍｍにすると、電線の表面（外観）に肌荒れが発生する虞があるためである。この実施例２の評価試験結果を以下の表２に示す。

According to the above evaluation test results, when the exit diameter A of the extrusion die is 1 to 1.5 times the outer diameter of the electric wire, the total score of the evaluation test is 2 or 3, and the peel strength between the insulator layer and the conductor ( (Hereinafter referred to as “adhesive strength”), and it was found that the amount of generated sea cucumber was also reduced. In this case, it has been found that a magnification of 1 is more preferable because the total score is 2 points, and the amount of occurrence of the mean is further reduced.
(Example 2)
In the second embodiment, the length (mm) of the B portion, which is the land with respect to the outer diameter of the electric wire (product) after manufacture, is 5 different lengths (specifically, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm). Then, the amount of occurrence of the sealant and the adhesive strength (peeling strength between the insulator layer and the conductor) corresponding to each magnification were measured, and the evaluation points of the same five-stage evaluation as in the above-mentioned examples were given. In addition, the evaluation test was not performed about the length shorter than 1 mm. The reason for this is that if this length is set to 0 mm, the surface (appearance) of the electric wire may be roughened. The evaluation test results of Example 2 are shown in Table 2 below.

上記評価試験結果により、電線外径に対するＢ部長さを１ｍｍ〜３ｍｍにすると、評価試験合計点数が２点又は３点となり、密着力を低下させると共にメヤニ発生量を低下させることが分かった。この場合、電線外径に対するＢ部長さを１ｍｍ〜２ｍｍとすると、評価試験合計点数が２点となり、密着力がさらに低下してより好ましいことが分かった。
（実施例３）
本実施例３においては、第１流路部Ｃ部の角度（°）を異なる５つの角度（具体的には、２０°、３０°、３５°、４０°、５０°）とし、この各倍率に対応するメヤニ発生量及び密着力（絶縁体層と導体の剥離強度）をそれぞれ測定して上述の各実施例と同様の５段階評価の評価点をつけた。なお、２０°より小さい角度に関する評価試験を行わなかった。この理由は、これ以上角度を小さくすると押出用ダイの長さが長くなり、部品単価が高くなるためである。この実施例３の評価試験結果を以下の表３に示す。

From the above evaluation test results, it was found that when the length of the portion B with respect to the outer diameter of the electric wire was 1 mm to 3 mm, the total number of evaluation tests was 2 or 3, which reduced the adhesion and reduced the amount of generated spots. In this case, it was found that when the length of the B portion with respect to the outer diameter of the electric wire is 1 mm to 2 mm, the total number of evaluation tests is 2, and the adhesion is further reduced, which is more preferable.
(Example 3)
In the third embodiment, the angle (°) of the first flow path part C is set to five different angles (specifically, 20 °, 30 °, 35 °, 40 °, 50 °), and the respective magnifications. By measuring the amount of generation and adhesion (peeling strength between the insulator layer and the conductor) corresponding to the above, evaluation points of the same five-stage evaluation as in the above-described examples were given. In addition, the evaluation test regarding an angle smaller than 20 ° was not performed. The reason for this is that if the angle is further reduced, the length of the extrusion die becomes longer and the unit cost of the parts becomes higher. The evaluation test results of Example 3 are shown in Table 3 below.

上記評価試験結果により、押出用ダイの流路の入口部からテーパ状に縮径する第１流路部（Ｃ部）の開き角度が２０度〜３５度であると、評価試験合計点数が２点又は３点となり、密着力を低下させると共にメヤニ発生量を低下させることが分かった。この場合、Ｃ部の開き角度が２０度〜３０度であると、評価試験合計点数が２点となり、密着力がさらに低下してより好ましいことが分かった。
（実施例４）
本実施例４においては、製造後の電線（製品）外径に対する押出用ニップルＤ部の角度（°）を異なる５つの角度（具体的には、２０°、３０°、３５°、４０°、５０°）とし、この各倍率に対応するメヤニ発生量及び密着力（絶縁体層と導体の剥離強度）をそれぞれ測定して上述の各実施例と同様の５段階評価の評価点をつけた。なお、２０°より小さい角度に関する評価試験を行わなかった。この理由は、これ以上角度を小さくすると押出用ニップルの長さが長くなり、部品単価が高くなるためである。この実施例４の評価試験結果を以下の表４に示す。

According to the evaluation test result, when the opening angle of the first flow path part (C part) that is tapered from the inlet part of the flow path of the extrusion die is 20 degrees to 35 degrees, the total number of evaluation test points is 2. It became a point or 3 points | pieces, and it turned out that an adhesive force is reduced and a generation amount of a mean is reduced. In this case, it was found that when the opening angle of the part C is 20 ° to 30 °, the evaluation test total score is 2 points, and the adhesion is further reduced, which is more preferable.
Example 4
In Example 4, five angles (specifically, 20 °, 30 °, 35 °, 40 °, and different angles (°) of the nipple D portion for extrusion with respect to the outer diameter of the electric wire (product) after manufacture are described. 50 degree), and the amount of generation of the sealant corresponding to each magnification and the adhesion strength (peeling strength between the insulator layer and the conductor) were measured, respectively, and evaluation points of the same five-level evaluation as in the above-described examples were given. In addition, the evaluation test regarding an angle smaller than 20 ° was not performed. The reason for this is that if the angle is further reduced, the length of the nipple for extrusion becomes longer and the unit price of the parts becomes higher. The evaluation test results of Example 4 are shown in Table 4 below.

上記評価試験結果により、押出用ニップル（Ｄ部）の開き角度が２０度〜３０度であると、評価試験合計点数が２点となり、密着力を低下させると共にメヤニ発生量を低下させることが分かった。

From the above evaluation test results, it is understood that when the opening angle of the extrusion nipple (D part) is 20 degrees to 30 degrees, the total number of evaluation tests is 2, which reduces the adhesion force and reduces the amount of generated scum. It was.

  As described above, in manufacturing a normal electric wire, when the adhesion between the insulating layer constituting the covering portion and the conductor constituting the wire becomes high, for example, the insulating layer at the end of the electric wire is peeled to remove the wire. The problem that the workability of removing the insulator layer is lowered when the connection terminal is exposed and crimped to this part is solved by the mold for the electric wire extruder according to the present invention and the method of manufacturing the electric wire using the same. We were able to.

  In other words, the adhesion between the insulator layer and the conductor has been reduced, and the peelability of the insulator layer has been greatly improved. As a result, the end workability accompanying the peeling of the insulator layer has been improved and the workability of the wire harness has also been improved. This eliminates the problem of product yield.

In addition, when the material constituting the insulator layer is an olefin resin and a metal hydroxide, there is a problem of the occurrence of the above-mentioned mess, but the amount of the mess can be reduced as much as possible in the process of manufacturing a normal electric wire. It was. As a result, a product with no flaws on the surface of the cable can be formed by reducing the occurrence of mains, and a stable product can be manufactured. Therefore, the poor product yield caused by the mains that has been generated in the past has been improved, and the cable can be manufactured at low cost. Specifically, an electric wire (product) having no scratch on the surface can be formed, and a stable product can be produced.
According to the die for an electric wire extruder and the method for producing an electric wire using the same according to the present invention, it is possible to simultaneously solve the adhesion force between the insulator layer and the conductor and the yield.

It is sectional drawing of one Embodiment of the metal mold | die for electric wire extruders which concerns on this invention. It is sectional drawing of the die | dye for conventional extruders.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Die for extruders 2 Outlet part 4 Hole part 5 1st curved part (R part)
6 Die entrance part 8 Second bending part (R part)
DESCRIPTION OF SYMBOLS 11 Extruder die 12 Extrusion die 12a One side (inlet side) end surface 12b The other side (outlet side) end surface 13 Extrusion nipple 13a Tip part 13b Taper part 13d Outlet part 13e End surface 13f Outer peripheral surface 15 Flow path 16 Inlet side Channel section (first channel section)
16a Inlet part 16b Inner wall surface 17 Outlet side channel part (second channel part)
17b Outlet portion α First flow passage portion inner wall surface opening angle β Taper portion opening angle A Inner diameter (outlet diameter) of flow passage portion 17
B Length of flow path part 17 (Land length)
C 1st channel part D Nipple for extrusion F Channel

Claims (2)

An extrusion die having a flow path for a thermoplastic resin member; and an extrusion nipple that is concentrically disposed in the flow path and through which a wire to be coated is inserted, and is formed by extrusion molding with the thermoplastic resin member. In the mold for the extruder of the wire to be coated,
The flow path of the extrusion die has a first flow path portion that is tapered from the inlet portion and a second flow path portion having a predetermined diameter that communicates with the reduced diameter portion of the first flow path portion. The opening angle of the first flow path part is 20 to 35 degrees, the inner diameter of the second flow path part is 1 to 1.5 times the outer diameter of the electric wire, and the length of the second flow path part is 0. And less than 3mm,
The extrusion nipple has a taper portion whose diameter decreases in a taper shape from the inlet side of the flow path, and the opening angle of the taper portion is 20 degrees to 30 degrees. Mold. An extrusion die having a flow path for a thermoplastic resin member; and an extrusion nipple that is concentrically disposed in the flow path and through which a wire material to be coated is inserted, and is formed by extrusion molding with the thermoplastic resin member. A thermoplastic resin member composed of an olefin resin and a metal hydroxide is continuously poured into the mold for the extruder of the electric wire to be coated from the inlet portion of the first flow path portion, and the wire material is A method of manufacturing an electric wire by manufacturing an electric wire made of a wire covered with the thermoplastic resin member by continuously inserting from the expanded diameter portion of the nipple for extrusion,
The flow path of the extrusion die has a first flow path portion that is tapered from the inlet portion in a tapered shape, and a second flow path portion having a predetermined diameter that communicates with the reduced diameter portion of the first flow path. The opening angle of the first flow path part is 20 to 35 degrees, the inner diameter of the second flow path part is 1 to 1.5 times the outer diameter of the electric wire, and the length of the first flow path part is 0. The extrusion nipple has a taper portion that is tapered from the inlet side of the flow path, and the opening angle of the taper portion is 20 degrees to 30 degrees. A method for producing an electric wire, comprising:

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