JP2016076325A - Cable, cable with enclosure, and cable production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cable in which the thermal fusion between the insulator and the sheath in an insulated wire is prevented, as well as the adhesion between the insulator and the sheath is improved.SOLUTION: Provided is a cable 1 having a plurality of an insulated wire 4 in which a conductor 2 is covered with an insulator 3 by a crosslinked resin material, and a sheath 5 covering the periphery of the plurality of insulated wire 4 with a non-crosslinked resin material, and in which there is applied an aliphatic acid metal salt between the insulated wire 4 and the sheath 5, to fill the gap between insulated wire 4 and sheath 5 with an aliphatic acid metal salt, thereby a water traveling through the gap is blocked.SELECTED DRAWING: Figure 1

Description

The present invention relates to a cable, a cable with a housing, and a method for manufacturing the cable, and more specifically, a cable in which a plurality of insulated wires whose conductors are covered with an insulator made of a resin material are bundled and covered with a sheath made of a resin material. The present invention relates to a cable with a housing and a method for manufacturing the cable.

A cable is used in which a plurality of insulated wires whose conductors are covered with an insulator made of a resin material are combined to form an insulating core, which is covered with a sheath made of a resin material.
With such a cable, when carrying out branch connection processing in wiring or the like or connector connection processing, the sheath is peeled away from the cable? Processing is necessary to expose the insulating core.
In this case, when the sheath made of the resin material is formed around the insulated wire having the insulator made of the resin material, the insulation of the insulated wire and the sheath is caused by the heat of the resin material of the sheath melted by the extruder. It becomes difficult to peel off the sheath from the cable due to heat fusion. For example, in a cable configured to use polyvinyl chloride (PVC) resin as an insulator of an insulated wire and the same PVC resin as a sheath material, PVC is coated around the PVC resin. It becomes easy to fuse.

  In order to prevent thermal insulation between the insulation of the insulated wire and the sheath as described above, conventionally, a stripping agent such as talc is applied to the surface of the multi-core insulated wire, and the sheath material is covered and molded in this state. Is done. Here, the presence of the release agent prevents thermal fusion between the insulator of the insulated wire and the sheath.

  For example, Patent Document 1 discloses a technique for preventing heat fusion between an insulator and a sheath. For example, Patent Document 1 discloses that an insulator made of a vinyl chloride resin is extruded on a conductor, and then a vinyl chloride resin is sheathed. A vinyl insulated vinyl sheathed cable is disclosed in which a PVC paste gelled material containing normal paraffin and silicone is interposed between the insulator and the sheath.

  Further, in Patent Document 2, in the process of applying a microcapsule in which a release agent is encapsulated to the surface of an insulating core having a conductor coated with an insulator, and extruding and covering the insulating core with a sheath material, A synthetic resin sheath cable is disclosed in which a microcapsule is broken by heat and a release layer is formed between an insulated wire core and a sheath.

JP-A-7-249318 JP-A-8-264033

When a release agent such as talc is applied between the insulator of the insulated wire and the sheath, there is a minute gap between the insulated wire and the sheath. With respect to the gap, moisture is condensed between the insulated wire and the sheath at the end of the cable, and the moisture moves through the gap in the cable. At this time, if a circuit board or the like is connected to the other end of the cable, there is a problem that a circuit on the board is short-circuited by moisture.
In other words, when a release agent such as talc is applied to improve the peeling characteristics between the insulator and the sheath of the insulated wire, the adhesion between the insulator and the sheath deteriorates, and the gap between these interfaces is reduced. There is a problem that the water moves and causes a problem.

  Patent Documents 1 and 2 describe the use of zinc stearate as a release agent as a conventional technique. However, in both Patent Documents 1 and 2, it is described that the use of zinc stearate is not preferable because non-uniform coating amount or scattering into the environment occurs.

  The present invention has been made in view of the above circumstances, and in a cable having a configuration in which a sheath is covered around an insulated wire, while preventing thermal fusion between the insulator of the insulated wire and the sheath, the insulator and It aims at providing the manufacturing method of the cable which improved the adhesiveness with a sheath, the cable with a housing | casing, and a cable.

  A cable according to the present invention is a cable having a plurality of insulated wires whose conductors are covered with an insulator made of a crosslinked resin material, and a sheath where the periphery of the plurality of insulated wires is covered with a non-crosslinked resin material, A fatty acid metal salt is applied between the insulated wire and the sheath, and a gap between the insulated wire and the sheath is filled with the fatty acid metal salt to block water transmitted through the gap.

  The cable with a casing according to the present invention is a cable with a casing having the cable according to the present invention and a resin casing attached to one end of the cable by molding.

  A cable manufacturing method according to the present invention is a cable manufacturing method including a step of covering a sheath of a non-crosslinked resin material around a plurality of insulated wires whose conductors are coated with an insulator of a crosslinked resin material, In the step of covering the sheath, a fatty acid metal salt is applied between the insulated wire and the sheath, and the gap between the insulated wire and the sheath is filled with the fatty acid metal salt and transmitted through the gap. A method of manufacturing a cable in which water is blocked.

  According to the present invention, in a cable having a configuration in which a sheath is covered around an insulated wire, the thermal insulation between the insulator of the insulated wire and the sheath is prevented, and the adhesion between the insulator and the sheath is improved. It is possible to provide a cable through which water does not travel, a cable with a housing, and a method for manufacturing the cable. Although the present invention uses a fatty acid metal salt, the pulling force does not vary, and there is no problem that the fatty acid metal salt is scattered around.

It is a figure which shows the structural example of the cable by this invention. It is a figure which shows roughly the structural example of the cable with a housing | casing by this invention. It is a figure which shows the measurement result of the immersion length of the ink for evaluating sheath pull-out force and water-stopping property. It is a figure for demonstrating the water-stop evaluation method.

First, embodiments of the present invention will be listed and described.
(1) The invention relating to the cable of the present application includes a plurality of insulated wires whose conductors are covered with an insulator made of a crosslinked resin material, and a sheath in which the periphery of the plurality of insulated wires is covered with a non-crosslinked resin material. A cable, a metal salt of a fatty acid is provided between the insulated wire and the sheath;
It is a cable in which the metal salt of the fatty acid is filled in the gap between the insulated wire and the sheath to block water transmitted through the gap. As a result, in a cable having a configuration in which a sheath is covered around an insulated wire, a cable in which the insulation between the insulator and the sheath of the insulated wire is prevented and the adhesion between the insulator and the sheath is improved can be obtained. .

(2) It is preferable that the resin material of the said insulated wire and the resin material of the said sheath are the same kind resin. Thereby, adhesiveness can be improved with the same kind of resin.
(3) The sheath is preferably a non-crosslinked resin. The sheath is preferably a non-crosslinked resin as long as it meets the requirements of mechanical strength and heat resistance.
(4) It is preferable that the insulated wire is a twisted pair wire in which two insulated wires are twisted. Thereby, it is less susceptible to noise than a cable in which insulated wires are juxtaposed in parallel. Insulation wires are also superior to wires that are juxtaposed in parallel in terms of cable bending resistance (hardness to break when repeatedly bent). Although a minute gap is formed between the insulated wire and the sheath because of the twisted wire, the present invention can fill the gap, and is particularly effective when the insulated wire is a twisted wire.

(5) The invention relating to the cable with housing of the present application is a cable with housing having the cable and a resin housing that is molded and attached to the cable at one end of the cable. As a result, a cable with a housing in which the housing is integrally formed with the cable in which the insulation between the insulator and the sheath of the insulated wire is prevented and the adhesion between the insulator and the sheath is improved is obtained.
(6) It is preferable that the resin material of the said insulated wire, the resin material of the said sheath, and the material of the said resin housing | casing are the same kind resin. Thereby, adhesiveness is good with the same kind of resin material, and water stoppage can be improved.

(7) The invention according to the cable manufacturing method of the present application is a cable manufacturing method including a step of covering a sheath of a non-crosslinked resin material around a plurality of insulated wires whose conductors are coated with an insulator of a crosslinked resin material. In the method of covering the sheath, a fatty acid metal salt is provided between the insulated wire and the sheath, and a gap between the insulated wire and the sheath is filled with the fatty acid metal salt. This is a cable manufacturing method in which the water transmitted through the gap is blocked. Thus, in a cable having a configuration in which a sheath is covered around an insulated wire, a method for manufacturing a cable that prevents thermal fusion between the insulator and the sheath of the insulated wire and improves the adhesion between the insulator and the sheath Is obtained.

[Details of the embodiment of the present invention]
Specific examples of the cable and the cable manufacturing method according to the present invention will be described below with reference to the drawings. In addition, this invention is not limited to these illustrations, All the changes within the meaning and range equivalent to a claim are included.

FIG. 1 is a diagram showing a configuration example of a cable according to the present invention. The cable 1 includes two insulated wires 4 constituting an insulated core and a sheath (outer jacket) 5 that covers the periphery of the insulated wires 4. The insulated wire 4 can be a twisted pair wire in which two insulated wires are twisted to make it less susceptible to noise. The insulated wire 4 includes a conductor 2 and an insulator 3 made of a resin material that covers the periphery of the conductor 2.
The conductor 2 is made of, for example, a tin-plated copper alloy wire having high flexibility. The insulator 3 is molded from a crosslinked resin material.
As the insulator 3, for example, a cross-linked polyvinyl chloride (PVC) resin is used. The cross-linked PVC provides a cable having solder resistance and heat resistance. As the sheath 5, for example, a heat-resistant PVC resin is used. Heat resistant PVC makes the cable heat resistant and oil resistant. The sheath 5 is preferably a non-crosslinked resin as long as it satisfies the requirements of mechanical strength and heat resistance.

The material which comprises the cable 1 is not limited to said example, Another material can be applied suitably. For example, as the resin material of the insulator 3 or the sheath 5 of the insulated wire 4, one or more resins selected from the following group, rubber, or elastomer can be used.
Polyolefin resin (ultra low density polyethylene, low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene resin, ethylene-methyl acrylate copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-butyl acrylate copolymer resin, Ethylene-vinyl acetate copolymer resin),
Polyester resin, polyurethane resin, polyamide resin, ionomer resin,
Rubber or elastomer (chlorinated polyethylene resin, ethylene-propylene rubber, chloroprene rubber, natural rubber, styrene elastomer, silicone rubber, etc.).
These resins, rubbers or elastomers can be combined with additives (such as flame retardants, antioxidants, lubricants, cross-linking aids, various fillers, etc.) to meet requirements for heat resistance and mechanical strength.
By crosslinking these resins, requirements for heat resistance and solder resistance can be satisfied.

The cable of this embodiment provides the metal salt of a fatty acid to the interface between the insulated wire 4 constituting the insulating core and the sheath 5 in the above configuration. In this embodiment, zinc stearate is added as an example of a metal salt of a fatty acid.
Zinc stearate is in the form of powder at room temperature, and powder zinc stearate is attached to the insulated wire 4. In the case of stearic acid, it is difficult to adhere to the insulated wire 4, but zinc stearate adheres uniformly to the surface of the insulated wire 4. The amount of zinc stearate attached to the insulated wire 4 can be physically adjusted. Specifically, the twisted insulated wire 4 is passed through a box filled with zinc stearate, and then the excess zinc stearate is removed with a roller, and a predetermined amount of zinc stearate is twisted into the twisted insulated wire 4. Can be attached.
In the insulated wire of the present invention, the conductor 2 preferably has a cross-sectional area of 0.15 mm ² or more and 0.5 mm ² or less. When the insulated wire of this size is twisted and covered with the sheath, a minute gap formed between the insulated wire and the sheath can be filled.

  With the zinc stearate adhered to the surface of the insulated wire 4, the sheath 5 is extrusion coated. Since the two insulated wires 4 are twisted in pairs, the outer surface of the twisted wires has irregularities. Although the sheath enters the dent on the outer surface of the twisted wire, a minute gap is still generated between the twisted wire and the sheath. During extrusion coating of the sheath 5, the zinc stearate adhering to the surface of the insulated wire 4 is melted by the heat of the molten resin material of the sheath 5, and enters the minute gap between the insulated wire 4 and the sheath 5. Disappears. The insulated wire 4 and the sheath 5 are in close contact with the zinc stearate sandwiched therebetween. Further, it is considered that a part of the molten zinc stearate permeates the insulator 3 and the sheath 5 of the insulated wire 4. Since the covering resin of the insulated wire 4 is cross-linked, the covering resin of the insulated wire 4 is not deformed excessively when the sheath 5 is extruded and the gap between the insulated wire 4 and the sheath 5 is eliminated. As a result, water that is transmitted between the insulated wire 4 and the sheath 5 is blocked.

  Thus, the melted zinc stearate fills the gap between the insulated wire 4 and the sheath 5, thereby improving the adhesion force and the water stoppage between the insulated wire 4 and the sheath 5. At this time, the adhesion force between the sheath 5 and the insulated wire 4 tends to be improved by raising the extrusion temperature of the sheath 5 (resin temperature at the time of coating) to the melting point of zinc stearate or higher (for example, about 150 ° C.). In the embodiment according to the present invention, the adhesion between the insulator 3 and the sheath 5 of the insulated wire 4 is in the range of 0.05 to 50 (N / cm). Preferably, it is in the range of 0.1 to 30 (N / cm). More preferably, it is in the range of 0.5 to 10 (N / cm).

  Moreover, since zinc stearate has lubricity, it becomes possible to peel the insulated wire 4 and the sheath 5 at the interface by applying mechanical stress when the sheath 5 is peeled. The zinc stearate contained in the cable 1 adheres to the insulated wire 4 in the form of a powder and then melts and flows once when the sheath 5 is covered and formed, and is solidified again to be in a layer or film state. For this reason, when the sheath 5 is peeled off, it is not in the form of a powder, and no scattering like talc occurs. With such a configuration, the heat insulation between the insulator 3 and the sheath 5 of the insulated wire 4 is prevented, the adhesion between the insulator 3 and the sheath 5 is improved, and the cable 1 having a good water-stopping property is obtained. . Even when the cable of the present invention is immersed in water for one day (24 hours), the length of immersion of water in the cable can be 20 mm or less.

  FIG. 2 is a diagram schematically showing a configuration example of a cable with a housing according to the present invention. The cable with housing 10 is formed by being molded and connected to one end of the cable 1 having the configuration shown in FIG. 1 so that the housing 11 made of resin encloses the end of the cable 1. The cable sheath 5 and the exposed insulated wire 4 are melted by heat during molding, and the cable 1 and the housing 11 are integrated. The housing 11 constitutes a sensor main body such as a proximity sensor or a level sensor as an example, and a substrate 12 is provided inside the sensor main body. As the resin constituting the housing, PVC, polyester (polyethylene terephthalate (PET) or polybutylene terephthalate (PBT)), polyamide (nylon), or the like is used. The casing and the cable sheath are preferably made of the same type of resin (for example, both are PVC).

  On one end side of the cable 1, the conductor 2 of the insulated wire 4 is exposed and connected to the substrate 12 in the housing 11. The opposite end of the cable 1 is released into the atmosphere. The cable with housing 10 is distributed in this state, and is used by being appropriately incorporated in a target device or system.

When a release agent such as talc is applied between the insulator 3 and the sheath 5 of the insulated wire 4, a minute gap exists between the insulated wire 4 and the sheath 5, and the atmosphere is released to this gap. When moisture is condensed in the gap between the insulated wire 4 and the sheath 5 at the end portion of the cable 1, and the moisture moves in the cable 1 through the gap and reaches the substrate 12 in the housing 11, the substrate 12 The upper circuit is short-circuited, causing problems.
In this embodiment, since the zinc stearate is melted and solidified between the insulated wire 4 and the sheath 5 of the cable 1, the insulated wire 4 and the sheath 5 are brought into close contact with each other via the zinc stearate and stopped. Improves aqueous properties. Thereby, the influence of the water | moisture content to the board | substrate 12 in the housing | casing 11 can also be suppressed, without dew condensation water moving the inside of the cable 1. FIG.

  Further, when the casing 11 is molded with respect to the cable 1 at, for example, 150 to 280 ° C., the zinc stearate adhering to the surface of the insulated wire 4 is melted by the heat during the molding process. In a state where the temperature of the mold resin (polyester resin in this example) is relatively high, zinc stearate permeates into the coating resin of the insulated wire 4, and the mold resin comes into contact with the insulated wire 4 and adheres well. Even after the mold resin heated during molding is cooled and solidified, the adhesion between the insulated wire 4 and the mold resin is maintained. Again, the water traveling around the insulated wire 4 is blocked. When the covering resin material of the insulated wire 4 and the material of the sheath 5 are the same type of resin, their close contact is good and the water stoppage is particularly good. Further, if the material of the casing 11 is the same resin in addition to the covering resin material of the insulated wire 4 and the material of the sheath 5, they are melted and closely adhered, which is better in terms of blocking water.

In the said embodiment, although zinc stearate is provided as a metal salt of the fatty acid provided between the insulated wire 4 and the sheath 5, it is possible to use the following fatty acid metal salts in addition to zinc stearate. it can.
Lithium stearate (Li (OCOC ₁₇ H ₃₅ ) ₂ )
Magnesium stearate (Mg (OCOC ₁₇ H ₃₅ ) ₂ ) (*)
Calcium stearate (Ca (OCOC ₁₇ H ₃₅ ) ₂ ) (*)
Barium stearate (Ba (OCOC ₁₇ H ₃₅ ) ₂ )

Calcium laurate (Ca (OCOC ₁₁ H ₂₃ ) ₂ )
Barium laurate (Ba (OCOC ₁₁ H ₂₃ ) ₂ )
Zinc laurate (Zn (OCOC ₁₁ H ₂₃ ) ₂ ) (*)
Calcium ricinoleate (Ca (OCOC ₁₇ H ₃₂ ) ₂ )
Barium ricinoleate (Ba (OCOC ₁₇ H ₃₂ ) ₂ ) (*)
Zinc ricinoleate (Zn (OCOC ₁₇ H ₃₂ ) ₂ ) (*)
It is preferable that the metal salt of the fatty acid to be used has a melting point of 150 ° C. or lower (the one marked with * above).

(Example)
In order to evaluate the adhesion between the sheath 5 and the insulated wire 4, measurement of the sheath pull-out force and evaluation of water-stopping were performed. FIG. 3 is a diagram showing the measurement results of the immersion length of the ink for evaluating the sheath pull-out force and the water stoppage.
The measurement sample No. 1 is a configuration in which a sheath 5 is coated around an insulating core composed of two insulated wires 4, a cross-linked PVC is used for the insulator 3 of the insulated wire 4, and a non-cross-linked PVC is used for the sheath 5. This is an example in which zinc stearate is applied between the sheath 5.
The measurement sample No. 2 is a comparative example in which a sheath 5 made of non-crosslinked PVC is coated around the insulated wire 4 using the insulator 3 made of crosslinked PE, and no release agent is applied between the insulated wire 4 and the sheath 5. No. 3 is a comparative example in which the same insulated wire 4 and sheath 5 as those in the example were covered, and talc was applied between the insulated wire 4 and the sheath 5.
For the pulling force, 10 samples were measured in each example. The average value and coefficient of variation (standard deviation / average value) are shown in FIG. For the immersion length of the ink, five samples were measured in each example. Their average values are shown in FIG.

As a method for measuring the pulling force, a tensile tester was used to measure a load (pulling force (N / cm)) when the insulated wire 4 was pulled out from a cable having a sheath length of 100 mm at a pulling speed of 500 mm / min.
Moreover, water-stop evaluation was performed by the method shown in FIG. Here, the sheath 5 of the cable 1 as a measurement sample was partially peeled off and immersed in ink (ink ink) 20. The cable 1 is immersed in a U shape with respect to the ink 20 at room temperature, and the distance from the portion where the sheath 5 is peeled off and the insulated wire 4 is exposed to the bottom of the U shape is 100 mm. The distance from the surface to the U-shaped bottom was 120 mm. Then, the immersion length of the ink 20 between the insulated wire 4 and the sheath 5 after 60 minutes and 1 day after the immersion was measured to evaluate the water-stopping property.

As shown in the measurement results of FIG. In No. 2, the pulling force is 1.29 N / cm, and in the comparative example using talc, it is 0.66 N / cm. 1, the pull-out force was 1.14 N / cm.
Examples using zinc stearate are comparative examples No. The pulling force compared to 2 was a little small but almost the same. On the other hand, the examples are those of Comparative Example No. with talc applied. Compared to 3, the pulling force was clearly greater. Zinc stearate fills the gap between the insulator 3 and the sheath 5 of the insulated wire 4 and closes them together. However, since zinc stearate is a slippery material, the pulling force is slightly smaller than when there is no release agent. It is considered to be.
When the variation in the pulling force was compared, the variation in the example was smaller than that in the comparative example (the coefficient of variation was small). In particular, compared to the case of talc coating (No. 3), the variation coefficient of the example (No. 1) was less than half, obviously less variation, and it was found that zinc stearate can be stably applied as a release agent. .

  In addition, the ink immersion length for water-stop evaluation is No. as a comparative example. In No. 2, the ink immersion length was 177 mm after 60 minutes, 220 mm (maximum value) after one day (24 hours), No. 2 No. 3 was 220 mm (maximum value) after 60 minutes, whereas No. 3 was an example using zinc stearate. In No. 1, the ink immersion length was significantly reduced to 7 mm after 60 minutes, 15 mm on average after one day (24 hours), and 20 mm on the maximum. It is considered that the zinc stearate filled the gap between the insulated wire 4 and the sheath 5 and improved the water stoppage.

DESCRIPTION OF SYMBOLS 1 ... Cable, 2 ... Conductor, 3 ... Insulator, 4 ... Insulated electric wire, 5 ... Sheath, 10 ... Cable with housing | casing, 11 ... Housing | casing, 12 ... Board | substrate, 20 ... Ink.

A cable is used in which a plurality of insulated wires whose conductors are covered with an insulator made of a resin material are combined to form an insulating core, which is covered with a sheath made of a resin material.
In such a cable, when performing connection processing branch connection processing and a connector in the wiring or the like, by performing a skin peeling process for removing by peeling the sheath from the cable, it is necessary to expose the insulating core.
In this case, when the sheath made of the resin material is formed around the insulated wire having the insulator made of the resin material, the insulation of the insulated wire and the sheath is caused by the heat of the resin material of the sheath melted by the extruder. It becomes difficult to peel off the sheath from the cable due to heat fusion. For example, in a cable configured to use polyvinyl chloride (PVC) resin as an insulator of an insulated wire and the same PVC resin as a sheath material, PVC is coated around the PVC resin. It becomes easy to fuse.

Claims (7)

A plurality of insulated wires whose conductors are covered with an insulator made of a crosslinked resin material;
A sheath having a resin material coated around the plurality of insulated wires,
A cable in which a metal salt of fatty acid is provided between the insulated wire and the sheath, and a gap between the insulated wire and the sheath is filled with the metal salt of fatty acid to block water transmitted through the gap.   The cable according to claim 1, wherein the resin material of the insulated wire and the resin material of the sheath are the same kind of resin.   The cable according to claim 1, wherein the sheath is a non-crosslinked resin.   The cable according to any one of claims 1 to 3, wherein the insulated wire is a twisted pair wire in which two insulated wires are twisted.   A cable with a housing, comprising: the cable according to any one of claims 1 to 4; and a resin housing that is molded and attached to the cable at one end of the cable.   The cable with a housing according to claim 5, wherein a resin material of the insulated wire, a resin material of the sheath, and a material of the resin housing are the same kind of resin. A method of manufacturing a cable including a step of coating a sheath made of a resin material around a plurality of insulated wires covered with a conductor by an insulator made of a crosslinked resin material,
In the step of covering the sheath, a fatty acid metal salt is applied between the insulated wire and the sheath, and the gap between the insulated wire and the sheath is filled with the fatty acid metal salt and transmitted through the gap. A method of manufacturing a cable in which water is blocked.

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