JP2018098144A - Manufacturing method of wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a wire, capable of manufacturing a wire excellent in convenience and workability during use.SOLUTION: There is provided a manufacturing method of a wire 1 having a wire core twisted body 10 containing a plurality of twisted insulation wire cores 20 and a sheath 50 covering the wire core twisted body 10, which has (a) a process for winding a holding yarn 40 to an outer periphery of the wire core twisted body 10 in direct contact and (b) a process for forming the sheath 50 by extrusion processing a heat molten sheath material so as to have a tube shape covering the wire core twisted body 10 and the holding yarn 40. The holding yarn 40 is a yarn made by bundling a high melting point yarn 41 having a melting point higher than that of the sheath material and a low melting point yarn 42 having a melting point not higher than that of the sheath material.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method of manufacturing an electric wire including a wire core twisted body including a plurality of twisted insulated wire cores and a sheath covering the wire core twisted body.

  Conventionally, a method of manufacturing an electric wire having a plurality of insulated wire cores has been proposed. For example, one of the conventional electric wire manufacturing methods (hereinafter referred to as “conventional method”) includes a step of twisting a plurality of insulated wire cores to form a wire core twisted body, and a tight contact with the outer periphery of the wire core twisted body. A step of winding the press-wound tape so as to perform, and a step of forming a sheath so as to cover the press-wound tape (see, for example, Patent Document 1).

JP 2011-142070 A

  When the electric wire manufactured by the conventional method is actually used, the sheath and the press-wound tape are cut open and removed (so-called skinning is performed) in order to expose the insulated wire core to the outside of the electric wire. Furthermore, the sheath and the presser winding tape thus removed are collected and discarded (dispose of the waste). It is difficult to eliminate these treatments (peeling and disposal of waste) due to the structure of the electric wire manufactured by the conventional method.

  However, from the viewpoint of improving convenience and workability when using the electric wire, it is desirable to configure (manufacture) the electric wire so that these processes are simplified as much as possible.

  This invention is made | formed in view of the situation mentioned above, The objective is to provide the manufacturing method of the electric wire which can manufacture the electric wire which is excellent in the convenience and workability | operativity at the time of use.

In order to achieve the above-described object, the method of manufacturing an electric wire according to the present invention is characterized by the following (1) to (4).
(1)
A method for producing an electric wire comprising a twisted wire core including a plurality of twisted insulated wire cores and a sheath covering the twisted wire core,
Winding the holding yarn so as to be in direct contact with the outer circumference of the twisted wire core; and
Forming the sheath by extruding the melted sheath material so as to have a tube shape covering the wire core twisted body and the holding yarn, and
The holding yarn is
A high-melting yarn having a melting point higher than the melting point of the sheath material and a low-melting yarn having a melting point equal to or lower than the melting point of the sheath material are bundled.
It is a manufacturing method of an electric wire.
(2)
In the manufacturing method according to (1) above,
The holding yarn is
A twisted yarn in which the high melting point yarn and the low melting point yarn are twisted together, or a non-twisted yarn in which the high melting point yarn and the low melting point yarn are bundled together without being twisted,
It is a manufacturing method of an electric wire.
(3)
In the manufacturing method according to (2) above,
The holding yarn is
It is the twisted yarn, and is wound spirally around the outer periphery of the wire core twisted body in the same direction as the twisted direction of the twisted yarn in the step of winding the holding yarn.
It is a manufacturing method of an electric wire.
(4)
In the production method according to any one of (1) to (3) above,
The holding yarn is
The ratio of the cross-sectional area occupied by the high-melting yarn and the low-melting yarn in the cross section perpendicular to the axis of the holding yarn is 9: 1 to 5: 5.
It is a manufacturing method of an electric wire.

  According to the method for manufacturing an electric wire having the configuration (1), a holding yarn in which a low-melting yarn and a high-melting yarn are bundled is used in place of the presser winding tape according to the conventional method. A part of the yarn constituting the holding yarn (low melting yarn) is melted in the step of forming (extrusion molding) the sheath. As a result, only the other part (high melting point yarn) of the holding yarn that was not melted at the time of forming the sheath remains as the holding yarn in the electric wire manufactured by the manufacturing method of this configuration.

  Therefore, when the electric wire is used (when the skin is peeled off), the other part of the holding yarn (high melting point yarn) and the sheath may be removed. Therefore, compared with the electric wire manufactured by the conventional method, the excision process (peeling) becomes easier because it does not use the press-wound tape (generally, it requires more force than the holding thread and the waste is bulky). And the waste to be disposed of is also reduced.

  Therefore, according to the electric wire manufacturing method of this configuration, an electric wire excellent in convenience and workability during use can be manufactured.

  The manufacturing method of the electric wire having the above configuration also has another effect. Specifically, the holding yarn used in the present manufacturing method has a function of holding the wire core twisted body so as to maintain the twist of the wire core twisted body, like the press-wound tape of the conventional method. Regarding the holding of this wire core twisted body, the holding force required for the holding yarn before the sheath is provided differs from the holding force required for the holding yarn after the sheath is provided. Specifically, the latter holding force (after sheath formation) may be smaller than the former holding force (before sheath formation). This is because the twist of the core wire can be maintained even by the sheath provided so as to cover the core wire. In other words, after the sheath is formed, the twist of the wire core twisted body is maintained by both the holding yarn and the sheath. Therefore, as described above, even if a part of the holding yarn (low melting point yarn) is melted, the twist of the wire core twisted body is maintained. Therefore, this manufacturing method can manufacture the electric wire which can maintain both the maintenance of the function as an electric wire (twisting of an insulated wire core) and the excellent convenience and workability as an electric wire.

  Furthermore, in the method for manufacturing the electric wire having the above configuration, a yarn in which a high melting point yarn and a low melting point yarn are bundled is used as the holding yarn. As a result, for example, the high melting point yarn and the low melting point yarn are separated from each other (when the high melting point yarn and the low melting point yarn are individually wound around different positions of the wire core twisted body). Yarns are more durable against external impacts. This is because, for example, the magnitude of impact or the like exerted on one yarn can be reduced by dispersing external impact or the like on a plurality of yarns (not on a single yarn). Therefore, it is possible to prevent the holding yarn from being unintentionally disconnected in the process of manufacturing the electric wire.

  By the way, the “wire core twisted body” may include a structure different from the insulated wire core. For example, the twisted wire core may include inclusions provided between the insulated wire cores. Further, the “holding yarn” does not need to be provided so as to cover the entire outer periphery of the wire core twisted body as in the press-wound tape of the conventional method, but to the extent that the twist of the wire core twisted body can be maintained (for example, , In a spiral manner). In addition, the above-mentioned “sheath” does not necessarily need to be in close contact with the core wire and the holding yarn, and another layer (for example, an electromagnetic shield layer) is provided between the sheath and the core wire and the holding yarn. May be.

  Furthermore, in the above “step of winding the holding yarn so as to be in direct contact with the outer periphery of the wire core twisted body”, the holding yarn may be wound around the outer periphery of the previously formed wire core twisted body. The formation and the winding of the holding yarn may be performed all at once (for example, the holding yarn may be wound while forming the wire core twisted body). That is, the formation of the twisted wire core and the winding of the holding yarn may be performed as separate steps or as a single step.

  In addition, the electric wire (electric wire as a result) manufactured by the manufacturing method of the electric wire having the above-described configuration includes a wire core twisted body including a plurality of twisted insulated cores, and a holding yarn wound around the outer periphery of the wire core twisted body. (High melting point yarn) and a sheath covering the wire core strand and the holding yarn. Furthermore, this electric wire has a solidified body of a resin having a melting point lower than that of the resin constituting the holding yarn (that is solidified after the low-melting yarn is melted) along the holding yarn (high-melting yarn), or The low melting point resin (resin constituting the low melting point yarn) is dispersed in the member around the holding yarn (for example, in the sheath) (for example, the concentration of the low melting point resin in the peripheral region of the holding yarn is , Higher than other regions).

  According to the method for manufacturing an electric wire having the configuration (2), the holding yarn is configured as a twisted yarn or a non-twisted yarn of a high-melting yarn and a low-melting yarn. However, the twisted yarn is superior in durability to the above-described external impact and the like because the high-melting yarn and the low-melting yarn are less likely to separate from the untwisted yarn. Furthermore, twisted yarns are easier to handle because they are less likely to fray during use, compared to untwisted yarns. Therefore, it is preferable to use a twisted yarn as the holding yarn.

  According to the method for manufacturing the electric wire having the configuration (3), the holding yarn is wound around the wire core twisted body in the same direction as the twist direction of the twisted yarn (specifically, the S twist direction or the Z twist direction). Therefore, it is difficult to eliminate the state in which the holding yarn (twisted yarn) is twisted, compared to the case where the twisted yarn is wound in the opposite direction. Therefore, the advantage of using the twisted yarn as the holding yarn (durability to the above-described impact or the like) is more reliably exhibited.

  According to the method of manufacturing the electric wire having the configuration (4), the ratio of the cross-sectional area occupied by the high melting point yarn and the low melting point yarn in the cross section orthogonal to the axis of the holding yarn is included in the range of 9: 1 to 5: 5. The effect of maintaining the twist of the wire core strands (the ratio of the high-melting-point yarn to be left in the manufactured electric wire) and the convenience and work when using the electric wire The effect of improving the properties (the ratio of the low melting point yarn to be melted during production) can be more reliably achieved. Details of this effect will be described later.

  When the thickness of the high melting point yarn and the thickness of the low melting point yarn are the same, the ratio of the cross-sectional area can be rephrased as the ratio of the number of the high melting point yarn and the number of the low melting point yarn.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the electric wire which can manufacture the electric wire excellent in the convenience and workability | operativity at the time of use can be provided.

  The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

FIG. 1 is a series of process diagrams illustrating a method for manufacturing an electric wire according to the present invention. FIG. 1 (a) shows a step of forming a wire core twisted body, FIG. 1 (b) shows a step of winding a holding yarn around the wire core twisted body, and FIG. 1 (c) shows a wire core twisted body and a holding yarn. The process of forming the sheath to cover is shown. FIG. 2 is a schematic view illustrating the structure of the holding yarn shown in FIG. FIG. 2A shows a structure when the holding yarn is a twisted yarn, and FIG. 2B shows a structure when the holding yarn is a non-twisted yarn. FIG. 3 is a schematic view showing a state where a part of the sheath of the electric wire manufactured by the manufacturing method of FIG. 1 is removed. FIG. 4 is a schematic view showing the internal configuration of the electric wire manufactured by the manufacturing method of FIG. 4A is a cross-sectional view, and FIG. 4B is an enlarged view of a portion A in FIG. 4A. FIG. 5 is a schematic view illustrating the configuration of a manufacturing apparatus for manufacturing an electric wire by the manufacturing method of FIG.

  Hereinafter, the manufacturing method of the electric wire (henceforth "the electric wire 1") which concerns on this invention is demonstrated, referring drawings.

<Manufacturing method of electric wire>
The electric wire 1 which concerns on this embodiment is manufactured by the series of processes shown to Fig.1 (a), FIG.1 (b), and FIG.1 (c).

  The step shown in FIG. 1A is a step of forming the wire core twisted body 10. The wire core twisted body 10 is formed by twisting a plurality of insulated wire cores 20 and inclusions 30 by alternating twist (SZ twist). The insulated wire core 20 includes a conductor 21 and an insulator 22 that covers the conductor 21 (see FIG. 4). The number of the insulated wire cores 20 included in the wire core twisted body 10 is not particularly limited. In this example, the twisted core 10 has three insulated cores 20.

  Specifically, the wire core twisted body 10 alternately repeats the three insulated wire cores 20 and the inclusions 30 in one direction (S direction) and in the other direction (Z direction). Are alternately twisted (SZ twisting is performed) and bundled as one wire core twisted body 10. Thereby, the wire core twisted body 10 is in a state in which the S twist portions Ts and the Z twist portions Tz are alternately provided along the longitudinal direction. The distance in the longitudinal direction when one wire core (one wire core of the plurality of insulated wire cores 20) constituting the wire core twisted body 10 makes one rotation is referred to as “twisting pitch length”. .

  The step of FIG. 1B is a step of winding the holding yarn 40 around the wire core twisted body 10. In this step, the holding yarn 40 is wound around the outer periphery of the wire core twisted body 10 formed in the step of FIG. The holding yarn 40 has a strength capable of withstanding the tension applied by the centrifugal force when it is wound around the wire core twisted body 10 by the holding yarn winding portion 64 described later. The holding yarn 40 is wound around the wire core twisted body 10 in a spiral shape. The helical pitch length P of the holding yarn 40 is preferably 1 to 3 times the diameter D of the wire core twisted body 10. With the holding yarn 40 wound in this manner, the twisting pitch length of the wire core twisted body 10 is held to a sufficient degree in view of satisfying the design quality of the wire core twisted body 10. The number of the holding yarns 40 wound around the wire core twisted body 10 is not particularly limited. For example, the number of holding yarns 40 may be three or four from the viewpoint of maintaining the twist of the wire core twisted body 10 and the production efficiency of the electric wire 1. In addition, it is preferable that the winding pitch of each holding yarn 40 is 2 to 6 times the diameter D of the wire core twisted body 10.

  The step of FIG. 1C is a step of forming the sheath 50 on the outer side of the wire core twisted body 10. In this step, the outer periphery of the wire core twisted body 10 around which the holding yarn 40 is wound in the step of FIG. The sheath 50 is made of a synthetic resin such as polyvinyl chloride and polyethylene. The sheath 50 is formed by extruding a heat-melted sheath material so as to have a tube shape on the outer periphery of the wire core twisted body 10 around which the holding yarn 40 is wound. Thereby, the wire core twisted body 10 and the holding yarn 40 are protected by the sheath 50.

  As shown in FIG. 2, the holding yarn 40 is a yarn in which a high melting point yarn 41 and a low melting point yarn 42 are bundled. The high melting point yarn 41 is a yarn composed of fibers having a melting point higher than that of the sheath material (for example, polyester having such a melting point). The low melting point yarn 42 is a yarn composed of fibers having a melting point equal to or lower than the melting point of the sheath material (for example, nylon having such a melting point). As an example of “a yarn in which high-melting yarn 41 and low-melting yarn 42 are bundled” corresponding to a resin (polyvinyl chloride, polyethylene, or the like) that is generally used as a sheath material, ESPORAN (registered trademark) manufactured by Unitika Ltd. Can be mentioned.

  The holding yarn 40 may be a twisted yarn shown in FIG. 2A or a non-twisted yarn shown in FIG. However, the twisted yarn is superior in durability to impacts from the outside because the high-melting yarn 41 and the low-melting yarn 42 are less likely to separate from the untwisted yarn. Furthermore, twisted yarns are easier to handle because they are less likely to fray during use, compared to untwisted yarns. Therefore, it is preferable to use a twisted yarn as the holding yarn 40.

  When the holding yarn 40 is a twisted yarn, it is preferable to wind the holding yarn 40 around the wire core twisted body 10 in the same direction as the twist direction of the twisted yarn (the direction of the S twist or the direction of the Z twist). Thereby, compared with the case where it winds in the reverse direction of twist of a twisted yarn, the state where the holding yarn 40 was twisted becomes difficult to be eliminated. On the other hand, when the holding yarn 40 is a non-twisted yarn, there is no particular difference in effect in the direction in which the holding yarn 40 is wound around the wire core twisted body 10 (the direction of S twist or the direction of Z twist).

  In FIG. 2, for convenience, one high melting point yarn 41 and one low melting point yarn 42 are bundled. However, the holding yarn 40 may be composed of one or more high-melting yarns 41 and one or more low-melting yarns 42. Specifically, in a cross section orthogonal to the axis of the holding yarn 40, from the viewpoint of achieving both the effect of maintaining the twist of the wire core twisted body and the effect of improving convenience and workability when using the electric wire. It is preferable that the ratio of the cross-sectional areas occupied by the high melting point yarn 41 and the low melting point yarn 42 (if the thicknesses of both are the same, the ratio of the number) is in the range of 9: 1 to 5: 5. Hereinafter, this ratio is also referred to as “component ratio”.

<Structure of manufactured electric wire>
As shown in FIG. 3, the electric wire 1 manufactured by the method of FIG. 1 (the electric wire 1 as a result) has a wire core twisted body 10, a high melting point yarn 41 that is a part of the holding yarn 40, and a sheath 50. And. The low-melting-point yarn 42 that constitutes the holding yarn 40 together with the high-melting-point yarn 41 is melted in the process of extruding the sheath material to the outside of the wire core twisted body 10 (step of FIG. 1C).

  As a result of the melting of the low melting point yarn 42 in this manner, the electric wire 1 is a solidified body (low melting point yarn 42) of a resin having a lower melting point than the resin constituting the high melting point yarn 41 along the holding yarn 40 (high melting point yarn 41). Or the low melting point resin (resin constituting the low melting point yarn) is dispersed in the sheath 50 around the high melting point yarn 41 (for example, the high melting point yarn 41). The concentration of the low melting point resin in the peripheral region is higher than that in other regions).

  As shown in FIG. 4, the insulated wire core 20 and the sheath 50 are in close contact with each other at least partially. In other words, there is a portion where the inclusion 30 does not exist between the insulated wire core 20 and the sheath 50. Thereby, the diameter of the electric wire 1 can be reduced compared with the case where the inclusion 30 exists between the insulated wire core 20 and the sheath 50. In addition, when the thickness of the sheath 50 with respect to the outer diameter of the wire core twisted body 10 is determined by legal regulations or the like, the outer diameter of the sheath 50 can be reduced by the amount the outer diameter of the core twisted body 10 is reduced. The amount of material used for forming the sheath 50 (material cost, and thus the manufacturing cost of the electric wire 1) can be reduced.

<Manufacturing equipment>
Next, a manufacturing apparatus for manufacturing the electric wire 1 by the above manufacturing method will be described.

  As shown in FIG. 5, the manufacturing apparatus 60 that manufactures the electric wire 1 includes an insulated core supply part 61 and an inclusion supply part 62. The insulated wire core supply unit 61 is a general reel or the like, and a plurality of insulated wire cores 20 are drawn out from the insulated wire core supply unit 61. The inclusion 30 is fed out from the inclusion supply unit 62.

  An SZ twisted portion 63 is provided on the downstream side of the insulated wire core supply portion 61 and the inclusion supply portion 62. The SZ twisted portion 63 is fed with a plurality of insulating wire cores 20 fed out from the insulated wire core supply portion 61 and inclusions 30 drawn out from the inclusion supply portion 62. The SZ twisted portion 63 has a general SZ twisting mechanism, and a plurality of insulated wire cores 20 and inclusions 30 are twisted together by alternate twisting (SZ twisting) to form the wire core twisted body 10. ing.

  On the downstream side of the SZ twisted portion 63, a holding yarn winding portion 64 and a sheath forming portion 65 are sequentially provided. The holding yarn winding portion 64 has a general winding mechanism and winds the holding yarn 40 around the wire core twisted body 10 fed from the SZ twist portion 63 in a spiral shape. The sheath forming portion 65 has a general sheath forming mechanism, and forms the sheath 50 so as to cover the periphery of the wire core twisted body 10 around which the holding yarn 40 is wound.

<Evaluation of electric wire characteristics>
The inventor conducted a test for evaluating the characteristics of the electric wire 1 described above.

  Specifically, first, regarding the constituent ratio of the high-melting yarn 41 and the low-melting yarn 42 described above, with respect to a plurality of samples having different constituent ratios, the performance of maintaining the twist of the core 10 and the manufactured electric wire 1 The workability when using was evaluated. In each sample, a twisted yarn of a high melting point yarn 41 and a low melting point yarn 42 is used as the holding yarn 40. In this example, the above-mentioned Espolan (registered trademark) manufactured by Unitika Ltd. is used as a twisted yarn of the melting point yarn 41 and the low melting point yarn 42.

  About the maintenance performance of twist, it evaluated in two steps of A and B from a viewpoint of how much twist can be maintained. In this evaluation, there is no substantial twist breakage in evaluation A (the twisted pitch length of the wire core twisted body 10 does not change, or the twisted pitch length is the layer core of the wire core twisted body 10 even if there is a change. The evaluation B indicates that there is substantial twisting (the twisted pitch length of the wire core twisted body 10 is larger than 30 times the layer core diameter of the wire core twisted body 10). Represents). However, even in the case of evaluation B, there is no problem in the superiority over the electric wire manufactured by the above-described conventional method.

  The workability at the time of using the electric wire was evaluated in three stages of A to C. In this evaluation, evaluation A represents that the electric wire 1 is peeled off and the disposal of the waste by peeling is much easier than the electric wire manufactured by the above-described conventional method, and evaluation B is the peeling and waste. Although it is easier to dispose of the wire than the conventional method, the evaluation A represents inferior to the evaluation A, and the evaluation C represents inferior workability due to the twisted core 10. However, even in the case of evaluations B and C, there is no problem in the superiority over the electric wires manufactured by the conventional method described above. The skinning means that the sheath 50 and the high-melting-point yarn 41 are removed to expose the wire core twisted body 10 and the like.

  The results of the test described above are shown in Table 1 below. In this test, the “composition ratio” of the high-melting yarn 41 and the low-melting yarn 42 is changed by appropriately selecting the product number of the twisted yarn (Espolan described above).

  As shown in Table 1, as a result of the test conducted by the inventor, about the maintenance performance of the twist, when the composition ratio is 5: 5 or more (the ratio of the high melting point yarn 41 is increased) as in sample numbers 1 to 4, Since the amount of the high melting point yarn 41 remaining (not melted) in the electric wire 1 after production was large, it was confirmed that there was no substantial twisting (Evaluation A). On the other hand, when the composition ratio is smaller than 5: 5 as in sample numbers 5 and 6 (the ratio of the high melting point yarn 41 is small), it was confirmed that there was substantial twisting (Evaluation B).

  On the other hand, for workability at the time of using the electric wire, when the configuration ratio is larger than 9: 1 as in sample number 1 (the ratio of the high melting point yarn 41 increases), the amount of the remaining high melting point yarn 41 is large. It was confirmed that workability was slightly inferior (Evaluation B). On the other hand, when the composition ratio is included in the range of 9: 1 to 5: 5 as in sample numbers 2 to 4, it is confirmed that the amount of the remaining high-melting-point yarn 41 is appropriate, so that the workability is excellent. (Evaluation A). On the other hand, when the composition ratio is smaller than 5: 5 as in sample numbers 5 and 6 (the ratio of the high melting point yarn 41 is small), it is confirmed that workability is deteriorated due to the above-described twist breakage. (Evaluation C).

  From the above test results, it is clear that the constituent ratio of the high melting point yarn 41 and the low melting point yarn 42 is preferably included in the range of 9: 1 to 5: 5 (overall evaluation A). For reference, Table 1 also describes the comprehensive evaluation of examples in which the composition ratio is greater than 9: 1 (overall evaluation B) and examples in which the composition ratio is less than 5: 5 (overall evaluation C). ing.

  As described above, in the method for manufacturing the electric wire 1 according to the present embodiment, the holding yarn 40 in which the high melting point yarn 41 and the low melting point yarn 42 are bundled is used instead of the presser winding tape according to the conventional method. A part of the yarn constituting the holding yarn 40 (low-melting yarn 42) is melted in the step of forming (extrusion molding) the sheath 50. As a result, only the high melting point yarn 41 that was not melted at the time of sheath formation remains as the holding yarn 40 in the electric wire 1 manufactured by the present manufacturing method.

  Therefore, when the electric wire 1 is used (when the skin is peeled off), the high melting point yarn 41 and the sheath 50 may be removed. Therefore, compared with the electric wire manufactured by the conventional method, the excision treatment (peeling) is easy because the press-wound tape (generally, a larger force is required for excision and the waste is bulky than the holding yarn 40) is not used. And waste to be disposed of is reduced.

  Therefore, according to this manufacturing method, the electric wire 1 excellent in the convenience and workability at the time of use can be manufactured.

  Furthermore, the electric wire 1 is formed using the holding yarn 40 in which the ratio of the cross-sectional area occupied by the high melting point yarn 41 and the low melting point yarn 42 in the cross section orthogonal to the axis of the holding yarn 40 is in the range of 9: 1 to 5: 5. By being manufactured, the effect of maintaining the twist of the wire core twisted body 10 and the effect of improving the convenience and workability when using the electric wire 1 can be more reliably achieved.

  In addition, this invention is not limited to said each embodiment, A various modification can be employ | adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like can be made as appropriate. In addition, the material, shape, dimensions, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

  For example, in this embodiment (FIG. 1), the wire core twisted body 10 is SZ twisted. However, the wire core twisted body 10 may be S-twisted or Z-twisted. Furthermore, in this embodiment (FIG. 5), formation of the wire core twisted body 10 and winding of the holding yarn 40 around the wire core twisted body 10 are separate steps. However, these steps may be combined into one, and the formation of the wire core twisted body 10 and the winding of the holding yarn 40 may be performed collectively.

Here, the features of the embodiment of the method for manufacturing an electric wire according to the present invention described above are briefly summarized and listed in the following (1) to (4), respectively.
(1)
A method for producing an electric wire (1) comprising a twisted wire core (10) including a plurality of twisted insulated wire cores (20) and a sheath (50) covering the twisted wire core,
A step of winding the holding yarn (40) so as to be in direct contact with the outer periphery of the twisted wire core (FIG. 1 (b));
A step of forming the sheath (50) by extruding the melted sheath material so as to have a tube shape covering the wire core twisted body and the holding yarn (FIG. 1 (c)),
The holding thread (40)
A high-melting yarn (41) having a melting point higher than the melting point of the sheath material and a low-melting yarn (42) having a melting point equal to or lower than the melting point of the sheath material are bundled.
Electric wire manufacturing method.
(2)
In the manufacturing method according to (1) above,
The retaining thread (40) is
A twisted yarn in which the high melting point yarn (41) and the low melting point yarn (42) are twisted together, or a non-twisted yarn in which the high melting point yarn and the low melting point yarn are bundled without being twisted together.
Electric wire manufacturing method.
(3)
In the manufacturing method according to (2) above,
The retaining thread (40) is
It is the twisted yarn, and is wound spirally around the outer periphery of the wire core twisted body (10) in the same direction as the twisted direction of the twisted yarn in the step of winding the holding yarn.
Electric wire manufacturing method.
(4)
In the production method according to any one of (1) to (3) above,
The retaining thread (40) is
The ratio of the cross-sectional area occupied by the high melting point yarn (41) and the low melting point yarn (42) in the cross section perpendicular to the axis of the holding yarn is 9: 1 to 5: 5.
Electric wire manufacturing method.

DESCRIPTION OF SYMBOLS 1 Electric wire 10 Wire core twisted body 20 Insulated wire core 30 Inclusion 40 Retaining thread 41 High melting point yarn 42 Low melting point yarn 50 Sheath

Claims (4)

A method for producing an electric wire comprising a twisted wire core including a plurality of twisted insulated wire cores and a sheath covering the twisted wire core,
Winding the holding yarn so as to be in direct contact with the outer circumference of the twisted wire core; and
Forming the sheath by extruding the melted sheath material so as to have a tube shape covering the wire core twisted body and the holding yarn, and
The holding yarn is
A high-melting yarn having a melting point higher than the melting point of the sheath material and a low-melting yarn having a melting point equal to or lower than the melting point of the sheath material are bundled.
Electric wire manufacturing method. The manufacturing method according to claim 1,
The holding yarn is
A twisted yarn in which the high melting point yarn and the low melting point yarn are twisted together, or a non-twisted yarn in which the high melting point yarn and the low melting point yarn are bundled together without being twisted,
Electric wire manufacturing method. In the manufacturing method of Claim 2,
The holding yarn is
It is the twisted yarn, and is wound spirally around the outer periphery of the wire core twisted body in the same direction as the twisted direction of the twisted yarn in the step of winding the holding yarn.
Electric wire manufacturing method. In the manufacturing method as described in any one of Claims 1-3,
The holding yarn is
The ratio of the cross-sectional area occupied by the high-melting yarn and the low-melting yarn in the cross section perpendicular to the axis of the holding yarn is 9: 1 to 5: 5.
Electric wire manufacturing method.

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