CABLE

Abstract

A cable with improved durability is provided, which also allows for a smooth bending process. A cable formed by encasing a conductor section, in which a conductor is provided spirally in a longitudinal direction, with an insulating sheathing element having insulating properties, comprises: a conductor section formed by stranding a plurality of bare wires to form a core wire and arranging a plurality of the core wires in close contact in a ring shape; and a reinforcing section comprising a strip which includes a plurality of filaments of a fibrous material, and which is formed by compressing and accommodating the strip substantially linearly within a central space formed by the core wires in the ring shape in the conductor section, and wherein the strip is pressed into the central space.

Description

[Technical field]

[0001] The present invention relates to a cable formed from a plurality of conductors, and in particular to a cable with improved durability. [Technological background]

[0002] In recent years, the demand for cables with highly functional wiring has increased, partly due to developments in the robotics industry. Such cables are frequently used as high-current cables with large conductor cross-sections in applications such as the sliding sections of transport robots and welding power cables, where they are also subjected to repeated bending operations. Therefore, high durability against repeated bending over a long period, combined with high flexibility, is required.

[0003] To increase flexibility and durability, many conventional cables are designed with a structure in which a conductor, stranded in a concentric circular shape, is encased in polyvinyl chloride (PVC) insulation or a PVC sheath, so that the cross-section of the cable has a circular shape.

[0004] A conventional cable is known, for example, as a cable having a conductor with a plurality of subordinate strands which are stranded in a single-layer stranding structure, and in the configuration of the cross-section of the conductor which is cut along a direction perpendicular to its longitudinal direction, a void is formed in the middle of the plurality of subordinate strands, and a filler element is stranded between each of the subordinate strands (cf. patent literature 1).

[0005] Furthermore, a conventional cable is known, for example, in which several insulated core wires, each formed by covering a conductor with rubber or vinyl, are stranded together, with jute being inserted into a void between the insulated core wires and a sheath made of rubber or plastic being applied to the outer circumference of the insulated core wires (see patent literature 2). [List of literature references][Patent literature] [Patent Literature 1] Japanese patent with publication number 2020-119857 [Patent literature 2] Japanese utility model with publication number 56-76219 [Summary of the invention][Technical problem]

[0006] For example, a cable with a void formed in a central section of a plurality of subordinate strands, as described in patent literature 1 above, has a problem of low durability due to the tendency of the overall shape of the cable for the void in the central section to collapse during cable operation, easily leading to damage to the subordinate strands. A cable consisting of a plurality of individually coated, insulated core wires, as described in patent literature 2 above, also has the problem that it is difficult to obtain a sufficiently large current from the generated current, which is specified by the sum of the plurality of individually independent insulated core wires.Furthermore, such a cable, consisting of a multitude of insulated core wires, has problems with a larger outer diameter and increased manufacturing costs caused by splitting the inner conductor and insulation and wrapping the split conductors.

[0007] A cable with PVC insulation or a PVC sheath, such as a cable with a rubber or plastic sheath as described in patent literature 2, has the problem of low durability due to the low elasticity of the rubber, which causes local stress generation during a twisting or bending operation of the cable, easily leading to damage.

[0008] This means that conventional cables must have thick conductors if they are used as high-current lines. However, when the cable is bent or twisted, the thick conductors move within the insulation, and the conductors interfere with each other and become damaged, leading to a problem of reduced durability.

[0009] The present invention was made to solve the problems described above, and it is an objective of the present invention to provide a cable with improved durability while enabling a smooth bending process. [Solution to the problem]

[0010] As a result of extensive investigations, the inventors of the present invention have developed an arrangement structure and found a cable with improved durability, thus completing the present invention.

[0011] Therefore, a cable disclosed in the present application is a cable formed by encasing a conductor section, in which a conductor is provided spirally in a longitudinal direction, with an insulating sheathing element having an insulating property, wherein the cable comprises: a conductor section formed by stranding a plurality of bare wires to form a core wire and arranging a plurality of the core wires in close contact in a ring shape; and a reinforcing section comprising a strip which includes a plurality of filaments of a fibrous material, and which is formed by compressing and accommodating the strip substantially linearly within a central space formed by the core wires in the ring shape in the conductor section, and wherein the strip is pressed into the central space.

[0012] As described above, the cable disclosed in the present application is a cable formed by encasing a conductor section, in which a conductor is provided spirally in a longitudinal direction, with an insulating sheathing element having an insulating property, wherein the cable comprises: a conductor section formed by stranding a plurality of bare wires to form a core wire and arranging a plurality of the core wires in close contact in a ring shape; and a reinforcing section comprising a strip which includes a plurality of filaments of a fibrous material, and which is formed by compressing and accommodating the strip substantially linearly within a central space formed by the core wires in the ring shape in the conductor section, and wherein the strip is pressed into the central space.Accordingly, when the strip is pressed into the central section of the cable, it is packed within a volume exceeding a theoretically calculated cross-sectional area. This results in reduced contact pressure between the bare wires, and the damping strip in the central section supports the cable by exerting a force from the central section towards the outer circumference of the cable in a radius direction. This significantly improves the cable's durability during twisting processes, such as those performed by a welding robot, thereby reducing the occurrence of cable breaks.Furthermore, the configuration of the sub-strands, which use bare wires not insulated from each other by an insulating element or tape, allows for high processability, enabling easy connection at the end sections. This simplifies handling and reduces manufacturing costs compared to conventional technology, which requires stripping coated wires from numerous sub-strands for connection at the terminal sections.

[0013] In the cable disclosed in the present application, the cross-sectional area of ​​the strip in its natural position may be larger than the cross-sectional area of ​​the central space. Since the cross-sectional area of ​​the strip in its natural position is larger than the cross-sectional area of ​​the central space, as described above, the strip is pressed into the central section in a highly compressed state as an intervening material. This results in a cable in which the strip is kept in a highly flexible state, thus improving the damping properties of the strip and further enhancing the cable's durability.

[0014] In the cable disclosed in the present application, the strip is optionally made of synthetic fibers. Since the strip consists of synthetic fibers as described above, the strip of highly flexible synthetic fibers is pressed into the central section of the cable, and the strip is packed in the central section in a volume that further exceeds the theoretically calculated cross-sectional area. This results in reduced contact pressure between the bare wires, and the strip of synthetic fibers with damping properties in the central section supports the cable by a force from the central section of the cable towards the outer circumference of the cable in the radius direction. This results in a cable in which the strip is reliably kept in a soft state, further improving the cable's durability.

[0015] In the cable disclosed in the present application, the reinforcing section optionally accommodates the strip, which has fewer spiral turns within the central space than the conductor section. Since the reinforcing section accommodates the strip with fewer spiral turns within the central space than the conductor section, as described above, the strip, which is made of synthetic fiber and serves as an interleaving material, is pressed into the central section in a state close to a straight insertion, maintaining a highly linear condition. This results in the formation of a cable in which the strip is kept in a soft state, further improving the damping properties of the strip and the durability of the cable.

[0016] In the cable disclosed in the present application, the core wires are optionally in linear and close contact with each other at a multitude of points. Since the core wires are in linear and close contact with each other at a multitude of points, as described above, the bare wires have a larger contact surface area, and the occurrence of heat generation and voltage drop in the event of cable damage is reduced, thus further improving safety.

[0017] In the cable disclosed in the present application, the diameter of the conductor section may be 3 to 6 times the diameter of the core wire. Since the diameter of the conductor section is, as described above, 3 to 6 times the diameter of the core wire, the ratio of the core wire diameter to the conductor section diameter is optimized, which can reduce the stress and mutual interference of the bare wires due to a twisting process, thereby optimally increasing durability with an optimally filled core wire.

[0018] In the cable disclosed in the present application, the diameter of the core wire is optionally 8 to 60 times the diameter of each of the bare wires. Since the diameter of the core wire is 8 to 60 times the diameter of the bare wire, as described above, the ratio of the core wire diameter to the conductor diameter of the bare wire is optimized, which can reduce the occurrence of stresses due to a twisting process, thereby optimally increasing durability with an optimally filled core wire.

[0019] In the cable disclosed in the present application, a void is optionally formed in a region between adjacent conductor sections and the insulating sheathing element. Since a void is formed in a region between the adjacent conductor sections and the insulating sheathing element, as described above, the void acts as a buffer when the cable is used in repeated processes such as twisting operations in a welding robot or the like. This can significantly improve the cable's durability and reduce the occurrence of breaks, as well as eliminate the need for a cutting process of an element in the void, resulting in improved processability and reduced manufacturing costs.

[0020] In the cable disclosed in the present application, the conductor section optionally comprises 6 to 15 core wires. Since the conductor section contains 6 to 15 core wires, as described above, the ratio of core wire to conductor section is optimized, which can reduce the stress and mutual interference of the bare wires due to a twisting process, thereby optimally increasing the durability with an optimally filled core wire. [Brief description of the drawings] Fig. Figure 1 is a configuration diagram of a cable according to a first embodiment of the present invention. Fig. Figure 2 is an explanatory view to illustrate a relationship between adjacent core wires in the cable according to the first embodiment of the present invention. Fig. Figure 3 is an explanatory view to illustrate the diameter of a conductor section and the diameter of a core wire of the cable according to the first embodiment of the present invention. Fig. Figure 4 is an explanatory view to illustrate the diameter of the core wire and the diameter of a bare wire of the cable according to the first embodiment of the present invention. Fig. Figure 5 is an explanatory diagram illustrating the configuration of the cable according to the first embodiment of the present invention. Fig. Figure 6 is an explanatory view to illustrate the pressing of a strip into the cable according to the first embodiment of the present invention. Fig. Figure 7 is a configuration diagram of a cable according to a second embodiment of the present invention. Fig. Figure 8 shows calculation results of the outer diameter of a cable as a function of the number of core wires in the cable according to Example 1 of the present invention. Fig. Figure 9 illustrates measurement results of a cable twisting test according to Example 2 of the present invention. Fig. Figure 10 shows a result of the appearance of a respective cable (appearance of a conductor) during a cable twisting test according to Example 2 of the present invention. [Description of the embodiment](First embodiment)

[0021] As in Fig. Figure 1 shows that a cable according to a first embodiment is a cable formed by encasing a conductor section 1, in which a conductor is arranged spirally in a longitudinal direction, with an insulating sheathing element 3 having an insulating property, wherein the cable comprises: the conductor section 1, which is formed by stranding a plurality of bare wires 11 to form a core wire 12 and arranging a plurality of the core wires 12 in close contact in a ring shape; and a reinforcing section 2, which comprises a strip 21 comprising a plurality of filaments 21a made of a fibrous material, and which is formed by compressing and accommodating the strip 21 substantially linearly within a central space formed by the core wires 12 in the ring shape in the conductor section 1, and wherein the strip 21 is pressed into the central space.

[0022] The conductor section 1 is formed by arranging the core wires 12 in a spiral. That is, the conductor section 1 is formed by twisting the core wire 12 along its longitudinal direction.

[0023] The core wire 12 is formed by stranding a plurality of the bare wires 11. That is, the core wire 12 can be designed as a composite stranded conductor. The stranding method is not particularly restricted and can be either single-strand or collective stranding. The correlation between the stranding direction of the conductor (stranding direction of the parent conductor) and the collective direction is not particularly limited, but these directions are preferably the same, which can result in higher durability than in a case where the stranding direction is different.

[0024] The outer diameter of conductor section 1 is preferably equal to or greater than 0.85 times a theoretically calculated value (i.e., not equal to or less than 15% of the theoretical outer diameter value) and can, for example, be approximately 0.85 to 0.98 times the theoretically calculated value. If the bare wires 11 in conductor section 1 partially touch each other and flatten, the outer diameter of conductor section 1 decreases. If the outer diameter of the theoretically calculated value of conductor section 1 becomes excessively smaller than 0.85 times, the contact pressure becomes high and the durability decreases.

[0025] The conductor section 1 is not particularly limited as long as the conductor section 1 has a structure in which the core wires 12 are arranged concentrically in a circle, but preferably has a structure in which the core wires 12 are stranded and arranged in a single layer.

[0026] The material of the bare wire 11 is not particularly limited, but a copper wire, for example, can be used. From the standpoint of excellent durability, a metal-coated copper wire can be used. A soft copper wire, which has a smooth surface and is a soft electrical copper wire, can be used, and in this case, high flexibility and conductivity can be achieved compared to a hard copper wire, which is rigid. In this context, for example, a tinned soft copper wire can be used as the conductor forming the bare wire 11, resulting in improved corrosion resistance of the conductor surface.

[0027] The conductor section 1 is formed by arranging the multiple core wires 12 closely together in a ring shape. Due to the shape of the several closely spaced core wires 12, adjacent core wires 12 have electrical contacts with each other, and the core wires 12 arranged on the circular ring function as a single conductor bundle, thus easily achieving a high current and improving electrical safety. Furthermore, from the perspective that adjacent core wires 12 have electrical contacts with each other, it is also possible to easily comply with the safety standards for devices.

[0028] Preferably the adjacent core wires 12 are as shown in Fig. As shown in 2, the points a and b are in contact with each other at a multitude of points and lie close together and linearly along a straight line L formed by the multitude of points a and b. Similarly, as in Fig. As shown in Figure 2, adjacent core wires 12 are in contact with each other at a multitude of points c and d and are in close and linear contact along a straight line M formed by the multitude of points c and d. That is to say, from a macroscopic point of view, the adjacent core wires 12 appear to be in so-called surface contact with each other.

[0029] Since the core wires 12, as described above, are in linear and close contact with each other at a large number of points, they have a larger contact surface area. This mitigates heat generation and voltage drop in the event of cable damage, further improving safety. Furthermore, the fact that the core wire 12 is not insulated by another insulating element, tape, or the like results in improved durability and workability, which also enhances electrical safety.

[0030] As in Fig. As shown in Figure 3, the correlation between the diameter D of the conductor section 1 and the diameter d of the core wire 12 is not particularly limited, but the diameter D of the conductor section 1 is preferably 3 to 6 times the diameter d of the core wire 12 (including the two end values ​​3 and 6; this also applies in the following).

[0031] In other words, the diameter ratio D / d is preferably 3 to 6, and even more preferably the ratio D / d is 3.5 to 5.

[0032] If the diameter ratio D / d is less than 3, the mutual influence of the core wires 12 can be excessive. Conversely, if the diameter ratio D / d is greater than 6, the stranded outer diameter of the core wire 12 becomes large, which can easily lead to an increase in manufacturing costs and a further increase in the outer diameter.

[0033] If the core wires 12 are stranded in two layers, the core wires 12 in the first and second layers interfere with each other, which reduces durability. Therefore, the core wire 12 preferably has a single-layer structure and a diameter ratio D / d of 3 to 6.

[0034] Since the diameter of the conductor section 1, as described above, is 3 to 6 times the diameter of the core wire 12, the ratio of the diameter of the core wire 12 to the diameter of the conductor section 1 is optimized, which can reduce the stress and mutual influence of the bare wires 11 due to a twisting process, thereby optimally increasing the durability with an optimally filled core wire 12.

[0035] As in Fig. As shown in Figure 4, the diameter d of the core wire 12 is preferably 8 to 60 times the diameter d1 of the bare wire 11, although the correlation between the diameter d of the core wire 12 and the diameter d1 of the bare wire 11 of which the core wire 12 is made is not particularly limited. That is to say, the diameter ratio d / d1 is preferably 8 to 60 (including the two extreme values ​​8 and 60; this also applies in the following).

[0036] For example, the diameter ratio d / d1 is in the range of 8 to 60, regardless of whether calculated by collective stranding or by seven stranding, based on the calculation results under the conditions that the total cross-sectional area of ​​the cable is 8 to 55 mm². 2 the number of core wires 12 is 6 to 15 and the diameter of the strand (bare wire 11) is 0.08 to 0.12 mm.

[0037] For example, if a seven-strand stranding was carried out on the strands (bare wires 11), a diameter ratio d / d1 was calculated under the conditions that the total cross-sectional area of ​​the cable was 8 mm². 2 , the number of core wires 12 equals 15 and the diameter of the strand (bare wire 11) was 0.12 mm, to 9. If the same seven-stranding was carried out, a diameter ratio d / d1 of 56 was further calculated, for example under the conditions that the total cross-sectional area of ​​the cable is 55 mm². 2 , the number of core wires 12 was equal to 6 and the diameter of the strand (bare wire 11) was 0.08 mm.

[0038] For example, if the collective stranding was carried out on the strands (bare wires 11), the diameter ratio d / d1 was calculated under the conditions that the total cross-sectional area of ​​the cable was 8 mm² 2, the number of core wires 12 equals 15 and the diameter of the strand (bare wire 11) was 0.12 mm, to 8. If the same collective stranding was carried out, a diameter ratio d / d1 of 49 was calculated, for example under the conditions that the total cross-sectional area of ​​the cable is 55 mm² 2 the number of core wires was 12, which was equal to 6, and the diameter of the strand (bare wire 11) was 0.08 mm.

[0039] Since the diameter of the core wire 12, as described above, is 8 to 60 times the diameter of the bare wire 11, the ratio of the diameter of the core wire 12 to the conductor diameter of the bare wire 11 is optimized, thereby reducing the occurrence of stresses due to a twisting process and optimally increasing the durability of the bare wire 11, which is filled to an optimal degree.

[0040] The number of core wires 12 is not particularly limited, but is preferably 6 to 15 (including the two end values ​​6 and 15; the same applies below), and more preferably 8 to 12. The number can be, for example, 10, which increases the durability of the stranding.

[0041] The reason for this is that durability decreases when the number of these core wires 12 is less than 6, and that the outer diameter and manufacturing costs increase when the number is more than 15. If the core wires 12 are stranded in two layers to avoid an increase in the outer diameter, the core wires 12 in the first and second layers, which form the double-layer stranding, affect each other, which reduces durability.

[0042] Since the conductor section 1, as described above, is formed from 6 to 15 core wires 12, the ratio of the core wires 12 to the conductor section 1 is optimized, which reduces stresses and mutual interference between the bare wires 11 due to a twisting process, thus optimally increasing the durability with an optimally filled core wire 12.

[0043] As in Fig. As shown in Figure 5, the strip 21 is compressed in the reinforcement section 2 and essentially linearly positioned along a linear direction A in the central space formed by the annular core wire 12 of the conductor section 1. That is, it is a configuration in which the strip 21 is pressed into the central space. A press fit is a condition in which pressure is applied for insertion.

[0044] As in Fig. As shown in Figure 5, the essentially linear shape of strip 21 means that strip 21 is accommodated in the central space in a shape along the linear direction A, which is the running direction (longitudinal direction) of the cable, and maintains an essentially linear shape.

[0045] Even if strip 21, as in Fig. 5 shown, if the strip is partially or locally curved to a certain degree, this is included in the condition that the strip 21 is essentially linear as long as the overall shape runs along the linear direction A and can be described as linear.

[0046] Preferably, the strip 21 is arranged in the central space with fewer spiral turns than the spiral turns of the conductor section 1. This means that, in contrast to the bare wire 11 in a spirally twisted state, the strip 21, as intervening material, is formed in a straight state close to an unstrapped state.

[0047] As a result, the strip 21, acting as an intervening material, is pressed into the central section in a state approaching a straight state, maintaining a linear state with high straightness. This leads to the formation of a cable in which the strip 21 is held in a soft state instead of a stranded and hard state, thereby further improving the damping properties of the strip 21 and further improving the durability of the cable.

[0048] The strip 21 is formed from a multitude of filaments 21a made of a fibrous material. As in Fig. As shown in 6(a), the strip 21 can, for example, be formed from a multitude of twisted filaments 21a.

[0049] The strip 21 is preferably configured such that the diameter e of the cross-section in its natural position, as shown in Fig. 6(b) shown, is larger than the diameter E of the cross-section of the central space formed closer to the center of the cable than the conductor section 1, as shown in Fig. 6(c) is shown.

[0050] That's how it is, as in Fig. Figure 6(d) shows that the cross-sectional area of ​​the strip 21, which forms the reinforcing section 2 in its natural position, is designed to be larger and more voluminous than the cross-sectional area of ​​the central space of the cable. In this way, the strip 21 is pressed into the central section as an intervening material in a highly compressed state, resulting in a cable in which the strip 21 is kept in a highly flexible state. This improves the damping properties of the strip 21 and further enhances the durability of the cable.

[0051] Strip 21 is not particularly limited as long as strip 21 consists of a fibrous material and can be made of a natural material, but from the point of view of uniform quality and cost, it is preferably made of a synthetic fiber.

[0052] Examples of synthetic fibers include polyester resins, acrylic resins, rubber resins, vinyl alkyl ether resins, silicone resins, polyamide resins, urethane resins, fluorocarbon resins, and epoxy resins. From the perspective of ease of handling, polyester is preferred, more preferably polyester, and even more preferably cotton-like polyester. For example, polyester nonwovens twisted into a three-strand braid can be used as third filaments 21a, and a plurality of these three-strand braids can be used as an interlayer material for the strip 21.

[0053] Since the strip 21 is made of synthetic fiber as described above, it is pressed into the central section of the cable. The strip 21 is packed in the central section in a volume that further exceeds the theoretically calculated cross-sectional area, resulting in reduced contact pressure between the bare wires 11. Furthermore, the synthetic fiber strip 21, with its damping properties, supports the cable in the central section by exerting a force from the central section towards the outer circumference of the cable in the radius direction. This creates a cable structure in which the strip 21 is kept in a flexible state, further improving the cable's durability.

[0054] The insulating sheathing element 3 for encasing the conductor section 1 is not particularly limited, as long as the insulating sheathing element 3 is an insulating element. The insulating sheathing element 3 can, for example, be formed from several elements: a retaining band 31 that encases the outer circumference of the conductor section 1 and holds and fixes the conductor section 1 in a band shape; an insulating element 32 that encases the outer circumference of the retaining band 31; and a sheath 33 that encases the outer circumference of the insulating element 32 and prevents damage to the cable.

[0055] The material of the retaining tape 31 is not particularly limited, but a fluoropolymer tape, for example, can be used. Examples of such fluoropolymers include various materials such as tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), tetrafluoroethylene / ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), chlorotrifluoroethylene / ethylene copolymer (ECTFE), and polytetrafluoroethylene (PTFE). The use of such a tape prevents the conductor section 1 from becoming constricted inside the cable due to its high sliding properties, high elongation, and flexibility, thus further improving durability.

[0056] The insulating element 32 is preferably made of a material with higher flexural elasticity than the material of the sheath 33.

[0057] The material of the insulating element 32 is not particularly limited, as long as the insulating element 32 is an insulating element, but various resins such as a thermoplastic ester-based elastomer (TPEE), a thermoplastic olefin-based elastomer (TPO), a thermoplastic urethane-based elastomer (TPU) and a thermoplastic amide-based elastomer (TPAE) can be used. More specifically, materials such as polyester (PEs), polybutylene terephthalate (PBT), polyethylene (PE), polypropylene (PP), polyamide 6 (PA6), polyamide 11 (PA11), polyamide 12 (PA12), polyethylene terephthalate (PET), polybutylene naphthalate (PBN), polyvinylidene fluoride (PVDF), ethylene tetrafluoroethylene copolymer (ETFE), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), ethylene vinyl alcohol copolymer (EVOH), acrylonitrile butadiene styrene (ABS), ethylene vinyl alcohol (EVA), or polyimide (PI) can be used.

[0058] For example, a polyester elastomer can be used as the insulating element 32. In this case, polyester has a higher flexural elasticity than PVC, and its hardness prevents twisting stress from concentrating on the end section. Furthermore, the insulating element 32 can be formed by tube extrusion, thus maintaining durability without compromising the conductor. This reduces the stress on the core wire 12 during cable manufacturing and results in a high-quality cable.

[0059] The stiffness of the insulating element 32 is not particularly limited, but from the point of view of improving durability, the insulating element 32 preferably has a stiffness of 50 MPa to 400 MPa, and even more preferably a stiffness of 70 MPa to 300 MPa. In this context, it is advantageous to select the insulating element 32 of such a quality that it can be bent 10 million times even with a bending radius of 6D (mm).

[0060] The material of the sheath 33 is not particularly limited, but examples include polyvinyl chloride (PVC), polyethylene (PE), and fluorinated ethylene propylene (FEP) (Teflon, registered trademark). For ease of handling, polyvinyl chloride (PVC) can be used, as it is flexible, has proven effective in cables for welding robots, and is flame-retardant and oil-resistant.

[0061] In this way, the strip 21 is pressed into the central section of the cable, and the strip 21 is packed into a housing volume that exceeds the theoretically calculated cross-sectional area. This results in reduced contact pressure between the bare wires 11, and the strip 21, with its damping properties in the central section, supports the cable by exerting a force from the central section of the cable towards the outer circumference in the direction of the radius. This significantly improves the cable's durability during twisting processes, such as those performed by a welding robot or similar equipment, thereby reducing the occurrence of cable breaks.

[0062] Furthermore, due to the configuration of the bare wires 11 (subordinate strands), which are not insulated from each other by an insulating element or tape, the connection at the terminal sections can be easily made and high processability achieved. This facilitates handling and allows for a reduction in manufacturing costs compared to conventional technology, which requires stripping the coated wires from a large number of subordinate strands that make up the cable for connection at the end sections. (Second embodiment)

[0063] As in the first embodiment, a cable 10 according to a second embodiment comprises a conductor section 1, the conductor section 1 and a reinforcement section 2, and as in Fig. As shown in Figure 7, a void 13 is formed in an area that is formed between the adjacent conductor sections 1 and an insulating sheathing element 3.

[0064] The void 13 preferably occupies at least part of the area formed between the adjacent conductor sections 1 and the insulating sheathing element 3. Preferably, the void 13 occupies the entire area.

[0065] Since the void 13 is formed in the area between the adjacent conductor sections 1 and the insulating sheathing element 3, as described above, the void 13 acts as a buffer when the cable is used in repeated processes, such as twisting operations by a welding robot or the like, thereby significantly improving the cable's durability and reducing the occurrence of breaks. Furthermore, this eliminates the need to cut an element in this area during cable manufacturing, thus improving processability and reducing manufacturing costs.

[0066] To further illustrate the features of the present invention, examples are given below, although the present invention is not limited by these examples. (Example 1)(1) Preparing the cable

[0067] According to the first embodiment described above, a cable according to Example 1 was manufactured using the following elements. <element> - Core wire 12: tinned soft copper wire (compound stranded wire) (each cable cross-section 2 mm²) 2 × 10) - Stripe 21: Polyester (interposed material with high damping properties) - Retaining band 31: Fluoride band - Insulating element 32: Polyester elastomer - Coat 33: PVC - Outer diameter of conductor section 1: 9.2 (theoretical calculation ratio) (2) Checking the number of core wires

[0068] The outer diameter of the cable depends on the number of core wires 12 (the number of core wires) that make up the cable. Fig. Figure 8 shows the result of the calculation of the outer diameter of a 22 mm 2 -Conductor in the case that the conductor is divided into 1 to 12 (the number of core wires is 1 to 12).

[0069] While the number of core wires is preferably 6 to 15 as described above, the following was determined based on the Fig. The measurement results shown in Figure 8 further confirm that, from the perspective of reducing the cable's outer diameter, a number of core wires is even more advantageously between 8 and 12. As a result, it was confirmed that the cable's outer diameter can be reduced, and a highly durable cable in a compact form can be achieved. (Example 2)

[0070] A twist strength comparison test was performed between the cable manufactured in Example 1 and a conventional HMVV(c10681)AWG4(22) / 1C cable (manufactured by DYDEN CORPORATION). As in Fig. As shown in Figure 9(a), the test conditions were as follows: the distance L between the fixed end and the working end of the target cable was 200 mm, the twist angle θ was t180° and the twist repetitions were 5 million.

[0071] The results achieved are in Fig. Figure 9(b) shows that the conventional cable exhibits a conductor strand (bare wire 11) breakage rate of 36.7%. In contrast, it was confirmed that the cable of the present example exhibits virtually no conductor strand (bare wire 11) breakage, i.e., a conductor strand (bare wire 11) breakage rate of 0.21%. Accordingly, the difference in durability compared to the conventional product was remarkable, and extremely high durability was confirmed.

[0072] Fig. Figure 10 shows the result of the appearance (conductor appearance) of each cable in the present twisting test. The results show that no conductor deformation occurred in the cable of the present example, whereas such deformation was confirmed in a cable of the conventional product after 5 million twisting cycles. The difference in durability compared to the conventional product was therefore also visually remarkable, and extremely high durability was confirmed. [List of reference symbols] 1 ladder section 11 bare wire 12 core wire 13 empty spaces 2 Reinforcement section 21 strips 21a Filament 3 insulating encasing element 31 Retaining strap 32 Insulating element 33 coat QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2020-119857

[0005] JP 56-76219

[0005] < / element>

Claims

[1] Cable formed by encasing a conductor section in which a conductor is provided spirally in a longitudinal direction with an insulating sheathing element having an insulating property, wherein the cable has: a conductor section formed by stranding a plurality of bare wires to create a core wire and arranging a plurality of the core wires in close contact in a ring shape; and a reinforcement section comprising a strip which includes a plurality of filaments of a fibrous material, and which is formed by compressing and accommodating the strip substantially linearly within a central space formed by the core wires in ring form in the conductor section, wherein the strip is pressed into the central space. [2] Cable according to claim 1, wherein a cross-sectional area of ​​the strip in its natural position is more voluminous than a cross-sectional area of ​​the central space. [3] Cable according to claim 1, wherein the strip is made of synthetic fibers. [4] Cable according to claim 1, wherein the reinforcement section accommodates the strip which has fewer spiral turns within the central space than spiral turns of the conductor section. [5] Cable according to claim 1, wherein the core wires are in linear and close contact with each other at a plurality of points. [6] Cable according to claim 1, wherein the diameter of the conductor section is 3 to 6 times the diameter of the core wire. [7] Cable according to claim 1, wherein the diameter of the core wire is 8 to 60 times the diameter of each of the bare wires. [8] Cable according to claim 1, wherein a void is formed in a region formed between the adjacent conductor sections and the insulating sheathing element. [9] Cable according to any one of claims 1 to 8, wherein the conductor section comprises 6 to 15 core wires.

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