JPH0644418B2 - Transport cable and method of manufacturing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a moving cable having excellent flex resistance and a manufacturing method for manufacturing the moving cable.

"Prior Art" Fig. 5 shows an example of a conventional moving cable.
This cable 1 consists of three insulated wire cores for power 2, 2, 2 and 2
The control insulated wire cores 3 and 3 and the grounded insulated wire core 4 are twisted together to form a twisted wire core 5, and a tape made of a polyester film is wrapped on the twisted wire core 5. A tape winding layer 6 is formed by winding, and a sheath 7 made of crosslinked polyethylene is extruded and covered on the tape winding layer 6.

[Problems to be Solved by the Invention] However, when the moving cable 1 having this structure was actually used and repeatedly bent, a swelling occurred in the cable 1.

This is because a space as shown by A in FIG. 5 is formed between the tape winding layer 6 and each of the insulated cores 2, 3 and 4, and when an external force such as bending or twisting is applied to the cable 1, the insulated cores are formed. It is considered that any one of 2, 3, 4 moves to this space A ..., causing uneven local bending of the insulating core.

For this reason, a full type cable in which the sheath 7 is directly extruded and covered directly on the twisted wire core 5 without tape winding so as to eliminate the space A ... If the sheath 7 is directly extruded and coated directly on the twisted wire core 5 which does not have a wire, a part of the twisted wire core 5 is untwisted and expanded by the resin pressure (for example, about 50 kg / cm ² ) at the time of extrusion coating. A birdcage phenomenon occurs, which causes a problem of product failure.

Therefore, it is an object of the present invention to obtain a solid type moving cable that does not cause swelling even when an external force such as bending or twisting is applied, without causing a birdcage phenomenon when the sheath is extruded and covered.

[Means for Solving the Problems] In the invention according to claim 1, a moving cable comprising a twisted wire core, an intermediate coating layer, and a sheath, wherein the twisted wire core has a plurality of insulated wires. The cores are twisted by forming irregularities on their outer periphery, and the intermediate coating layer is formed of a synthetic resin that is melted by heat during sheath extrusion coating,
The intermediate coating layer is closely coated on the irregularities of the outer periphery of the twisted wire core and is fully coated on the twisted wire core, and the sheath is
The solution was to make a structure in which the intermediate coating layer and the twisted core are closely fixed to each other by closely contacting the irregularities on the outer periphery of the intermediate coating layer, and the intermediate coating layer is fully coated.

In a second aspect of the present invention, a plurality of insulating cores are twisted together to form a twisted core having irregularities on the outer circumference, and the twisted cores are made of a synthetic resin which is melted by heat during extrusion coating of the outer sheath. The tape is wound to form an intermediate conductor having a gap between the twisted wire core and the synthetic resin tape, and the sheath is extruded and coated on the outer side of the intermediate conductor, and at the same time, the above-mentioned synthesis is performed by the heat and pressure during extrusion coating. An intermediate coating layer that adheres to the twisted core by melting a resin tape and a sheath that adheres to this intermediate layer are formed, and the gap is closed by the intermediate coating layer and the sheath, and the individual insulated cores of the twisted core The solution was to fix them tightly.

According to a third aspect of the present invention, there is provided a moving cable including a twisted wire core, an adhesive resin, and a sheath, wherein the twisted wire core forms a plurality of insulating wire cores with irregularities formed on their outer circumferences. The adhesive resin is formed of a synthetic resin that is melted by the heat during extrusion coating of the sheath, and the adhesive resin is formed by twisting and forming a gap between them. The gap is filled and filled, and the twisted wire core and the adhesive resin on the outer periphery of the twisted wire core are tightly covered and covered on the outside of the twisted wire core, and the twisted wire core and the adhesive resin are fixed to complete the sheath. The solution was to be extrusion coated.

According to a fourth aspect of the invention, a plurality of insulating wire cores are formed with gaps between them and irregularities are formed on their outer circumferences and twisted together, and the gaps between the plurality of insulating wire cores and the outer circumference of the insulating wire cores are formed. The adhesive resin is filled so as to fill the concave portion of the wire, and the sheath is then fully extruded and coated on the outer side thereof to melt the adhesive resin by the heat and pressure during the extrusion coating to form the twisted wire core and the adhesive resin. Forming a sheath in a closely contacted state was the solution.

According to a fifth aspect of the present invention, there is provided a moving cable comprising a twisted core, an adhesive resin, an intermediate coating layer and a sheath, wherein the twisted core has a plurality of insulating cores between them. Gaps are formed and the outer circumferences of these are twisted together to form concavities and convexities, and the adhesive resin is formed from a synthetic resin that melts due to heat during sheath extrusion coating. It is provided by filling the concave part of
The twisted wire core and the adhesive resin on the outer periphery of the twisted wire core are closely adhered to cover them, and the twisted wire core and the adhesive resin are fixed to form an intermediate coating layer, which is adhered to the intermediate layer. The solution was to use a structure in which the sheath is fully extruded and covered.

In the invention according to claim 6, a plurality of insulating wire cores are formed with a gap between them and unevenness is formed on the outer circumference thereof and twisted together, and the gap between the plurality of insulating wire cores and the outer circumference of the insulating wire core are Adhesive resin is filled so as to fill the recesses, and a synthetic resin tape that melts by the heat during extrusion coating of the sheath is wound around this outer periphery, and then the sheath is fully extruded and covered on the outer side of the tape for extrusion coating. The solution was to melt the adhesive resin and the synthetic resin tape by heat and pressure, and to form the intermediate coating layer and the sheath in a state of being in close contact with the stranded wire core and the adhesive resin.

[Operation] By taking the above configuration, it is possible to prevent untwisting of the twisted core during extrusion coating of the sheath, and to form a full sheath on the twisted core without causing a birdcage phenomenon. Therefore, even if bending or twisting is applied, the insulation core does not have any play, so that a cable without swelling can be obtained.

[Examples] In the inventions described in claims 1 and 2, as shown in FIG. 1, a sheath is extruded to a twisted wire core 5 formed by twisting a plurality of insulating wire cores 2, 3 and 4. When the synthetic resin cape that is melted by the heat at the time of coating is wound and the molten tape winding layer 8 is formed to form the intermediate conductor 15, the insulating cores 2, 3, 4 are formed.
As a result, irregularities are formed on the outer periphery of the twisted wire core 5, so that a gap is formed between the twisted wire core 5 and the molten tape winding layer 8. Here, as the synthetic resin forming the tape, polyethylene, irradiation cross-linked polyethylene, polypropylene, polyvinyl chloride, ethylene-vinyl acetate copolymer and the like can be used. When, for example, a cross-linked polyethylene having an extrusion temperature of about 200 to 230 ° C. is used as the sheath, a thermoplastic synthetic resin having a melting temperature of about 200 ° C. or less is used as the synthetic resin forming the tape. The thickness of the tape is 20-15
It is set to about 0 μm. If the tape thickness exceeds 150 μm, the deformation of the sheath during extrusion coating is insufficient, which is inconvenient. Further, the tape may be an adhesive tape having an adhesive layer on one side surface. In this case, as the adhesive layer, an acrylic-based or rubber-based adhesive is used in an amount of about 5
What is applied to a thickness of ˜20 μm is used. When such an adhesive tape is used, the adhesive layer is naturally attached to the twisted wire core 5 and wound. The tape may be wound in a normal wrapping manner, but the overlapping width is relatively small, for example, 1/6 wrap, so that the molten tape winding layer 8 does not become substantially thick and the sheath It is desirable that deformation under pressure during extrusion coating is not hindered.

The twisted wire core 5 provided with the molten tape winding layer 8
Then, the sheath 7 is extrusion-coated in a solid state by an extruder having a normal crosshead die. This sheath 7
In the case of full extrusion coating of the
The molten tape winding layer 8 is melted and softened by the heat of the molten resin, and the tape winding layer 8 that is melted and softened by the pressure of the molten resin is pushed into the twist gap of each insulating wire core. In this way, the sheath 7 is formed in a solid state on the outer circumference of the twisted wire core 5 through the intermediate coating layer 8a formed by melting and deforming the tape winding layer 8.

In such a manufacturing method, since the twisted wire core 5 is clamped and bound by the intermediate coating layer 8a, the insulated wire cores 2, 3 and 4 are twisted and twisted by the pressure of the molten resin, and the bird cage No phenomenon occurs. Further, in the case of using the adhesive tape, even if the adhesive tape is cut during the extrusion coating of the sheath 7, the adhesive tape is not separated from the twisted wire core 5, and the tape is clogged in the nipple of the die of the extruder. There is no obstacle.

In addition, in the moving cable having such a structure, since the sheath 7 has a solid covering structure, the insulated cores 2, 3 and 4 do not move even when subjected to bending or twisting, There is no swelling in the wire and no breakage of the wire core, especially the thin wire cores 3 and 4.

In the invention described in claims 3 and 4, each insulated wire core
When 2,3,4 are twisted together to form the twisted wire core 5, the molten adhesive resin is twisted into a void (twisted gap)
The adhesive resin 9 as shown in FIG.
The twisted wire core 5 is filled with. As the adhesive resin 9 used here, one having excellent flexibility and adhesiveness is used, and as a specific example, a hot melt type adhesive containing a modified polyolefin having a melting temperature of 100180 ° C. as a main component is used. Can be used. In addition, this adhesive resin 9
May be a semi-conductive material in which carbon or the like is mixed if necessary. Further, as a specific filling method of the adhesive resin 9, there is a method of continuously injecting the molten adhesive resin 9 into the twisted portion of the twisting machine by using an applicator and twisting.

Twisted wire core 5 filled with adhesive resin 9 and twisted together
Then, the sheath 7 is extruded and covered in a solid manner by a conventional method. If necessary, the twisted wire core 5 is further wound with a tape made of a synthetic resin which is melted by the heat during sheath extrusion and covered. The sheath 7 can also be fully extruded and coated. The tape used here has a thickness of 60 μ, for example.
It is possible to use a polyethylene tape having a thickness of about m, a polypropylene tape having a thickness of about 25 μm, or an adhesive tape having an adhesive layer having a thickness of about 10 μm formed on these tapes. In a case where a polyethylene tape or an adhesive polyethylene tape is wound, this tape is melted and pushed during extrusion coating of the sheath 7, and is joined and integrated with the sheath 7 and the adhesive resin 9 to form a tighter solid structure. .

Even in the moving cable having such a structure, since the insulating cores 2, 3 and 4 are joined and integrated by the adhesive resin 9,
The birdcage phenomenon during extrusion coating of the sheath 7 is prevented,
Further, since the adhesive resin 9 is filled in the twisting gap of the twisted wire core 5, the cable does not get wrinkled.

"Experimental example" (Experimental example 1) Three insulated insulated wire cores with an outer diameter of 7.7 mm, two insulated insulated core wires with an outer diameter of 3.5 mm, and an insulated insulated wire core with an outer diameter of 3.5 mm One strand (both of which the insulator is cross-linked polyethylene) was twisted to obtain a twisted core having an outer diameter of about 17 mm. Adhesive polyethylene tape (thickness 60μ on this twisted core
m polyethylene tape with a 10 μm thick acrylic adhesive layer formed on one side) wrapped with 1/6 wrap, and a sheath made of cross-linked polyethylene is fully extruded and covered on this to move the finished outer diameter of 21 mm. Got the cable for. The resin temperature during extrusion coating of the sheath was 230 ° C., and the resin pressure was 80 kg / cm ² .

The moving cable 1 thus obtained was attached to a bending tester as shown in FIG. 4 to inspect the bending resistance.
In the bending test apparatus shown in FIG. 4, one end of the moving cable 1 is fixed to the ceiling 10, a weight 11 of 50 kg is attached to the other end, and the moving cable 1 is wound around a moving pulley 12 having a diameter of 200 mm and a fixed pulley 13 having a diameter of 200 mm. The moving pulley 1
The cable 2 is moved vertically up and down by 50 cm to apply a bending load to the cable 1.

Then, the flexing resistance was evaluated by reciprocating the moving pulley to obtain the number of times of reciprocation of the pulley in which the generation of swelling of the cable and the disconnection of the wire core were recognized.

For comparison, the same test was carried out for the conventional moving cable shown in FIG. 5 (a polyethylene terephthalate tape having a thickness of 25 μm, which is wrapped by ½ wrap instead of the adhesive polyethylene tape). First result
Shown in the table.

(Experimental example 2) When twisting each insulated wire core used in Experimental example 1, modified polyolefin hot melt adhesive (Aaron melt PPET manufactured by Toagosei Kagaku Kogyo Co., Ltd.) was heated and melted at 150 to 160 ° C. Was poured into the twisting portion of the twisting machine to obtain a twisted wire core in which the bonding resin was filled in the twisting gap. After the adhesive polyethylene tape used in Experimental Example 1 was wrapped around the stranded wire core in 1/6 wrap, a sheath made of crosslinked polyethylene was similarly extrusion-coated.

The flex resistance of this cable was determined in the same manner as in Experimental Example 1. The results are shown in Table 2.

Similar results were obtained with a cable provided with a sheath made of polyvinyl chloride.

[Advantages of the Invention] As described above, according to the present invention, a full-sheath type moving cable having good bending resistance, in which swelling does not occur even when bending or twisting acts, is applied to a bird at the time of extrusion coating of the sheath. It can be obtained without the cage phenomenon. Furthermore, since an intermediate coating layer is provided in close contact with the irregularities on the outer periphery formed when twisting a plurality of insulating wire cores, and the sheath is fully extruded and coated on the outside of this intimate contact with the intermediate coating layer.
With the intermediate coating layer and the sheath, the individual insulated cores of the twisted cores can be securely restrained and fixed so as not to move.

Therefore, it is possible to obtain a moving cable that can endure reciprocating motion up to 10,000 times.

Also, since the intermediate coating layer consists of a synthetic resin tape that melts due to the heat when the sheath is extruded, it is completely adhered to the twisted wire core by the heat and pressure when extruding with the sheath and restrains the twisted wire core together with the sheath. Fix it. Therefore, the twisted core can be securely fixed.

Furthermore, if the adhesive resin is filled in the gaps and the recesses of the twisted cores, and the sheath is directly overlaid with the synthetic resin tape, or the sheath is directly extruded, the twisted cores can be It is possible to completely constrain and fix the insulated core of the twisted core with the intermediate coating layer and the sheath after the inside is completely closed. Therefore, it is possible to obtain an excellent moving cable in which swelling does not occur even when bending or twisting acts.

In addition, in the present invention, in addition to melting the molten tape winding layer with heat during sheath extrusion, the pressure during sheath extrusion is used to bring the molten tape winding layer into close contact with the irregularities of the twisted wire core. The intermediate coating layer can be surely brought into close contact with the mating wire core, and the sheath can be fully coated thereon.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 relates to a first example of the present invention, and is a cross-sectional view of a twisted wire core on which a molten tape winding layer is formed, and FIG. 2 is a sheath of FIG. A cross-sectional view of the
FIG. 3 relates to a second example of the present invention, and is a cross-sectional view of a twisted core in which an adhesive resin is filled in a twist gap,
Figure is a schematic configuration diagram showing a bending test device for moving cables,
FIG. 5 is a cross-sectional view showing a conventional moving cable. 1 ... moving cable, 2 ... insulating power core, 3 ...
Control insulation wire core, 4 ... Ground insulation wire core, 5 ... Twisted wire core, 7 ... Sheath, 8 ... Molten tape winding layer, 8a
…… Intermediate coating layer, 9 …… Adhesive resin, 15 …… Intermediate conductor.

Claims (6)

[Claims] 1. A moving cable comprising a twisted core, an intermediate coating layer, and a sheath, wherein the twisted core is formed by twisting a plurality of insulating cores with irregularities formed on their outer circumferences. The intermediate coating layer is formed of a synthetic resin that is melted by heat during sheath extrusion coating, and the intermediate coating layer adheres closely to the irregularities on the outer periphery of the twisted core and is fully formed on the twisted core. A cable for movement, characterized in that the sheath is covered, and the sheath is tightly adhered to the irregularities on the outer periphery of the intermediate coating layer, and the intermediate coating layer and the twisted wire core are closely fixed to each other, and the sheath is fully coated on the intermediate coating layer. 2. A synthetic resin tape that is formed by twisting a plurality of insulating cores to form a twisted core having irregularities on the outer periphery and then melting the heat on the outer periphery of the twisted cores when the sheath is extruded and coated. An intermediate conductor having a gap between the twisted wire core and the synthetic resin tape is formed by winding, and a sheath is extruded and coated on the outside of the intermediate conductor, and at the same time, the synthetic resin is formed by heat and pressure during extrusion coating. An intermediate coating layer that adheres to the twisted wire core by melting the tape and a sheath that adheres to this intermediate layer are formed, and the gap between the intermediate conductors is closed by the intermediate cover layer and the sheath to individually insulate the twisted wire core. A method for manufacturing a moving cable, characterized in that the core is closely fixed. 3. A moving cable comprising a twisted wire core, an adhesive resin, and a sheath, wherein the twisted wire core forms a plurality of insulating wire cores on their outer circumferences to form irregularities. A space is formed and twisted together, and the adhesive resin is formed of a synthetic resin that is melted by heat during extrusion coating of the sheath, and the adhesive resin fills the gap between the outer periphery of the twisted wire core and the inner side. The twisted wire core and the adhesive resin on the outer periphery of the twisted wire core are closely adhered to the outside of the twisted wire core to cover them, and the twisted wire core and the adhesive resin are fixed and the sheath is fully extruded and covered. A moving cable characterized by being formed. 4. A plurality of insulated wire cores are formed by forming a gap between them and forming a concavo-convex pattern on the outer periphery thereof and twisting them together.
The sheath is extruded so as to fill the gaps between the insulated cores and the recesses on the outer periphery of the insulated cores, and is filled with an adhesive resin made of a synthetic resin that melts due to the heat during coating, and then the sheath is fully extruded to the outside. A method for producing a moving cable, characterized in that the sheathing resin is formed by melting the adhesive resin by heat and pressure during coating and extrusion coating to form a sheath in a state in which the twisted wire core and the adhesive resin are in close contact with each other. 5. A moving cable comprising a twisted wire core, an adhesive resin, an intermediate coating layer, and a sheath, wherein the twisted wire core has a plurality of insulating wire cores with a gap therebetween. Formed and twisted by forming concavities and convexities on their outer circumference, the adhesive resin is formed of a synthetic resin that is melted by heat during extrusion coating of the sheath, and the adhesive resin is formed by twisting the wire core on the outer periphery of the concave portion and on the inner side. It is provided by filling the gap, and the twisted wire core and the adhesive resin on the outer periphery of the twisted wire core are closely adhered to and covered on the outside of the twisted wire core, and the twisted wire core and the adhesive resin are fixed to form an intermediate portion. A movement cable, characterized in that a sheathing layer is provided, and a sheath for tightly adhering the twisted core and the adhesive resin to the intermediate sheathing layer is tightly extruded and coated on the outside of the sheath. 6. A plurality of insulating wire cores are formed with a gap between them and irregularities are formed on the outer circumference thereof to be twisted together, and a gap between the plurality of insulating wire cores and a recess on the outer circumference of the insulating wire core are formed. Fill the adhesive resin so as to fill it, and wrap a synthetic resin tape that melts with the heat during extrusion coating of the sheath around this outer circumference, and then fully extrude the sheath on the outside to cover the heat during extrusion coating. A method for manufacturing a moving cable, characterized in that an adhesive resin and a synthetic resin tape are melted by pressure, and an intermediate coating layer and a sheath in a state of being in close contact with the twisted wire core and the adhesive resin are formed.