JP3050659B2 - Spiral forming method of coated filament - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for spirally forming a coated linear body obtained by extruding a high-molecular polymer onto a core material such as metal.

[0002]

2. Description of the Related Art Conventionally, in order to form a core wire such as a single metal wire into a spiral shape, the core wire is forcibly applied to a spiral forming die in which spiral grooves are engraved at a predetermined pitch on the outer periphery of a rod. When the core wire is pressed, plastic deformation is applied to the core wire to form the core wire into a spiral shape.

[0003]

However, the conventional spiral forming method of a core wire has no problem when the core wire is a single metal wire. When the coated wire body coated with is formed into a spiral shape, it is difficult to form into a desired spiral shape because the mechanical strength of the core wire material and the coating material greatly differ.

[0004] That is, when it is attempted to form a spirally coated sheathed wire in which the outer periphery of a core wire is coated with a high-molecular polymer by a conventional method, a pushing wire for forcibly pushing the sheathed wire into a mold is used. The soft covering material is deformed and damaged by the feed roller.Because the covering material exists on the outer periphery of the core wire even if the spiral molding die is used to form it at a predetermined pitch, sufficient plastic deformation should be applied to the core wire. Therefore, there was a problem that molding to a predetermined size was impossible.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a method for spirally forming a coated wire having a core wire coated with a high-molecular polymer in a spiral shape. The purpose is to provide.

[0006]

In order to achieve the above object, the present invention provides a first step of forming a core wire into a spiral shape using a spiral mold, and extruding the core wire following the first step. And a second step of extruding and coating a high-molecular polymer with a machine .

[0007]

As described above, when the core wire is formed into a spiral shape in the first step by using a spiral mold, the core wire can be easily formed into a spiral shape. Next, since the high-molecular polymer is extrusion-coated with the extruder on the core wire formed into a spiral shape in the second step, the coating layer can be easily formed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a coated striated body obtained by the method of the present invention.
A core wire 1 made of aluminum alloy, steel, aluminum steel clad material, or the like, an insulating layer 2 made of nylon, polycarbonate, or another polymer insulating material on the outer periphery of the core wire 1 and carbon mixed into the polymer insulating material to be semiconductive. A coating layer 4 comprising a semiconductive layer 3 is formed. As shown in FIG. 2, the covered wire A is wound around the outer circumference of an overhead power transmission line B or the like to prevent wind noise. The winding method is such that the semiconductive layer 3 is in contact with the overhead power transmission line B. When wound in this way, it is possible to prevent corona from being generated between the covered wire body A and the overhead power transmission line B.

Next, a method of forming the above-described coated filament A will be described. First, the core wire 1 is formed into a spiral shape. To form the core wire 1 into a spiral shape, FIG.
And an apparatus as shown in FIG. This device 10
An inlet wall 12 to which an inlet base 11 is fixed, and an outlet base 13
And a plurality of pairs of feed rollers 1 rotatably supported by the base 15.
6 and a spiral molding die 17 arranged at one end with the outlet wall 14. The inlet base 11, a plurality of pairs of feed rollers 16 and the outlet base 13 are arranged linearly. The plural pairs of feed rollers 16 are driven by a drive source (not shown). Further, the spiral molding die 17 is covered with a cover 18.

In order to form the core wire 1 into a spiral shape using the above-described apparatus, the core wire 1 inserted into the inlet mouthpiece 11 is passed through a plurality of pairs of feed rollers 16 and outlet mouthpieces 13 to form a spiral mold 17. Send to The core wire 1 sent into the spiral forming die 17 is a spiral forming die 1
7 is plastically transformed by passing through the spiral groove 19 formed in 7 to be formed into a spiral shape. Various spiral shapes can be formed by changing the pitch, direction, and the like of the spiral groove 19 formed in the spiral forming die 17.

Next, the coating step which is the second step will be described. Extruders 21 and 22 are provided before the spiral mold 17.
Is arranged, and the core wire 1 formed in a spiral shape is guided to the crosshead 23 and passed therethrough. The crosshead 23 has extruders 21 and 22
The insulating coating material and the semiconductive coating material are supplied, and the insulating layer 2 and the coating layer 4 of the semiconductive layer 3 are formed on the surface of the core wire 1 as shown in FIG.

Immediately after the formation of the coating layer 4, the coating layer 4 is cooled by arranging a cooling tank 24 at a position immediately after the coating, since the temperature is high and the heat is easily deformed if left as it is. Although not shown, a measuring and cutting device is arranged at the end of the cooling tank 24 to cut the long spiral striated body into fixed lengths.
A fixed length spiral wire can be manufactured continuously.

[0013]

As described above, according to the present invention, only the core wire is formed into a spiral shape in the first step.
The core wire can be easily formed. In addition, since the high-molecular polymer is extrusion-coated in the second step, a coating layer can be easily formed. Therefore, the spiral-shaped coated filament can be manufactured uniformly at low cost.

[0014]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a spiral striated body formed by the method of the present invention.

FIG. 2 is a front view of the spiral striated body formed by the method of the present invention in use.

FIG. 3 is a front view of an apparatus used in the method of the present invention.

FIG. 4 is a side view of an apparatus used in the method of the present invention.

[Explanation of symbols]

 A: Coated wire 1: Core wire 4: Coated layer 11: Inlet mouthpiece 13: Outlet mouthpiece 15: Main base 16: Plural pairs of feed rollers 17: Spiral molding die 19: Spiral groove 21, 22: Extruder 23: Cross head 24: Cooling tank

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-2-207935 (JP, A) JP-A-4-253536 (JP, A) JP-A-2-57223 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) H01B 13/00-13/32

Claims (1)

(57) [Claims] 1. A first step of forming a core wire into a spiral shape with a spiral mold, and a second step of extruding and coating a high-molecular polymer on the core wire with an extruder following the first step.
Spiral forming method of the coated filamentary body, comprising the steps of: