A mechanically resistant twisted unshielded signal cable

Abstract

The utility model discloses a kind of anti-mechanical damage twisted pair without sheath signal cable, from inside to outside sequentially include twisted pair core wire, first tape and second tape, each core wire in the twisted pair core wire is from inside to outside sequentially for conductor filling bulletproof silk, conductor and insulating layer, the first tape and second tape are single-sided tape adhesive hot melt milar tape, the adhesive surface of the first tape and second tape is oppositely arranged and is formed by baking sintering. The utility model is suitable for small installation space, need to resist bending, need to resist torsion, need to repeat motion, transmission signal and other scene use.

Description

Technical Field

[0001] This utility model relates to a signal cable and belongs to the field of cable technology. Background Technology

[0002] When the characteristic impedance of the signal cable matches that of the connected device, the signal can be transmitted smoothly and without loss; otherwise, signal attenuation or distortion may occur. If the impedance of the device and the cable is mismatched, the signal will encounter obstacles during transmission, which will not only lead to a decrease in signal quality but may also cause data loss or communication interruption. Proper impedance matching can significantly enhance signal integrity and the robustness of the communication system.

[0003] For the design structure of cables with solid insulation materials, the characteristic impedance is typically designed from the inside out as follows: 1. Twisted pairs are individually wrapped with aluminum foil, braided shielding, and sheath; 2. The overall cable assembly includes aluminum foil wrapping, braided shielding, and a sheath. 3. Twisted pair and sheath.

[0004] All three solutions can achieve the required characteristic impedance and remain stable within the tolerance range. However, for devices with higher impedance values ​​(such as a characteristic impedance of 120Ω), the diameter of a single strand of the twisted pair will increase with the increase in impedance, resulting in a larger overall cable diameter and significantly increased production costs. Solution 3 avoids the above problems, but still requires a sheath to constrain the twisted pairs and stabilize their pitch, preventing gaps between the cores and ensuring impedance stability. Since the sheath cannot be eliminated, this solution still cannot achieve the minimum overall cable diameter. For applications with limited installation space that require movement and signal transmission, conventional designs are insufficient. As is well known, the bending radius of cables increases with the wire diameter during use and installation. Forcing installation in confined space with a small bending radius will severely impact the cable's lifespan. Utility Model Content

[0005] In view of the above-mentioned defects in the prior art, the present invention aims to provide a mechanically damaged twisted pair unsheathed signal cable that reduces the cable diameter to suit the requirements of use in confined installation spaces while ensuring the service life and impedance matching of the signal cable.

[0006] The technical solution of this utility model is as follows: a mechanically resistant twisted pair unsheathed signal cable, which includes twisted pair core wires, a first wrapping tape and a second wrapping tape from the inside to the outside. Each core wire in the twisted pair core wires consists of a conductor filled with bulletproof wire, a conductor and an insulation layer from the inside to the outside. The first wrapping tape and the second wrapping tape are single-sided adhesive hot melt Mylar wrapping tapes. The adhesive surfaces of the first wrapping tape and the second wrapping tape are arranged opposite each other and are formed by baking and sintering.

[0007] Furthermore, the conductor is a silver-plated copper wire, and the conductor is evenly distributed around the conductor filled with bulletproof wire.

[0008] Furthermore, the stranding pitch of the conductor is 8 to 10 times the stranding outer diameter, and the conductor is stranded in the S direction.

[0009] Furthermore, the insulating layer is an ethylene-tetrafluoroethylene copolymer.

[0010] Furthermore, the twist pitch of the twisted pair is 10 times the outer diameter of the twisted pair.

[0011] Compared with the prior art, the advantages of the technical solution of this utility model are as follows: The double-layered adhesive tape is bonded together after baking and tightly wrapped around the twisted pair core wires, limiting the variation of the twist pitch and ensuring that there are no gaps between the core wires. This guarantees the stability of the characteristic group and allows for lossless and smooth signal transmission.

[0012] This invention eliminates the outer sheath structure of conventional signal cables, replacing it with a double-layer wrapping, which significantly reduces the outer diameter of the finished cable, making it lighter and greatly reducing production costs. It also saves installation space, making it suitable for applications with limited space and where movement is required.

[0013] In addition, while meeting the signal transmission requirements of normal cable use, the layout of silver-plated copper wire surrounding the bulletproof wire improves the service life of the core wire. Furthermore, the insulation is made of ethylene-tetrafluoroethylene copolymer with low dielectric constant and high tensile strength, which can withstand bending and torsion for up to 10 million cycles and ensures stable electrical performance. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a mechanically damaged, unsheathed twisted-pair signal cable as an example. Detailed Implementation

[0015] The present invention will be further described below with reference to the embodiments, but this is not intended to limit the present invention.

[0016] Please combine Figure 1 As shown, the mechanically damaged twisted-pair unsheathed signal cable of this utility model embodiment includes, from the inside out, twisted-pair core wires, a first wrapping tape 4, and a second wrapping tape 5. Each core wire in the twisted-pair core wire consists of, from the inside out, a conductor filled with a bulletproof wire 1, a conductor 2, and an insulation layer 3.

[0017] The cross-sectional area of ​​conductor 2 is determined according to the requirements of the signal cable. Conductor 2 uses IEC 60228 Category 6+ silver-plated copper wire, with the conductor filled with elastic wire 1 evenly arranged around it. The stranding pitch of conductor 2 is set to 8 times the outer diameter of the strand, and it is formed in one strand. In some embodiments, the stranding pitch can be set to 10 times the outer diameter of the strand. The specific structure of this embodiment is 26 / 0.08 silver-plated copper wire plus 200D elastic wire. Due to the excellent conductivity of silver-plated copper wire, it is particularly suitable for signal transmission. In signal transmission applications, silver-plated copper wire can better utilize the skin effect to ensure high-quality signal transmission. Since the diameter of a single conductor 2 wire is extremely fine at 0.08mm, the addition of the conductor filled with elastic wire 1 in the center not only ensures the flexibility of the conductor but also greatly improves the conductor's resistance to bending, torsion, and overall tensile strength, thus ensuring the mechanical strength of the cable during use.

[0018] Insulation layer 3 is made of ethylene-tetrafluoroethylene copolymer (ETFE) insulation, which has a low dielectric constant and high tensile strength. ETFE's low dielectric constant (2.6) and low dissipation factor (0.003) ensure that its dielectric properties remain essentially constant even under frequency and temperature variations, which is crucial for signal transmission. This means that during signal transmission, ETFE can reduce signal loss and distortion, improving signal transmission quality and stability. Furthermore, ETFE's high tensile strength (50MPa) and excellent impact resistance make the twisted-pair signal cable more durable, capable of withstanding certain mechanical stresses and environmental changes. The cable core consists of conductor 2, composed of conductor-filled bulletproof wire 1, ultra-fine silver-plated copper wire, and ETFE insulation layer 3. The core wires are twisted in pairs, with the twist pitch set at 10 times the outer diameter of the twist. This allows the core wires to form different compression and tension zones when the cable is subjected to bending stress, thus avoiding the occurrence of twisting phenomena and reducing the risk of core wire breakage.

[0019] While the core wires are twisted into pairs, two wrapping machines simultaneously wrap the twisted pair with a first wrapping tape 4 and a second wrapping tape 5. Both the inner first wrapping tape 4 and the outer second wrapping tape 5 are 0.025mm thick, single-sided adhesive-coated, high-temperature heat-melting Mylar wrapping tapes. The adhesive side of the first wrapping tape 4 faces outwards, and the unadhesive side faces inwards, contacting the surface of the core wire's insulation layer 3; the adhesive side of the second wrapping tape 5 faces inwards, contacting the adhesive side of the inner first wrapping tape 4, and the unadhesive side faces outwards. The overlap rate of both wrapping layers is set at 50%. After wrapping, the wires are baked and sintered at high temperature to form the final shape. Because the unadhesive side of the first wrapping tape 4 faces inwards and contacts the surface of the core wire's insulation layer 3, it will not stick to the surface of the insulation layer 3 after high-temperature baking and sintering, making it easy to remove the first wrapping tape 4 and the second wrapping tape 5 for further processing during use. The outer second wrapping tape 5 has its adhesive side facing inward, contacting the adhesive side of the inner first wrapping tape 4. After being baked and sintered at high temperature, the two wrapping tapes are tightly and reliably bonded together. In addition, the high overlap rate of 50% makes the wrapping tapes less likely to loosen during the cable's twisting, bending and other movements, thus ensuring stable characteristic impedance and stable signal transmission.

Claims

1. A mechanically damaged twisted-pair unsheathed signal cable, characterized in that, From the inside out, it includes a twisted pair core wire, a first wrapping tape, and a second wrapping tape. Each core wire in the twisted pair core wire consists of a conductor filled with bulletproof wire, a conductor, and an insulation layer from the inside out. The first wrapping tape and the second wrapping tape are single-sided adhesive hot-melt Mylar wrapping tapes. The adhesive surfaces of the first wrapping tape and the second wrapping tape are arranged opposite each other and are formed by baking and sintering.

2. The mechanically damaged resistant twisted-pair unsheathed signal cable according to claim 1, characterized in that, The conductor is a silver-plated copper wire, and the conductor is evenly distributed around the conductor filled with bulletproof wire.

3. The mechanically damaged resistant twisted-pair unsheathed signal cable according to claim 1, characterized in that, The stranding pitch of the conductor is 8 to 10 times the outer diameter of the strand, and the conductor is stranded in the S direction.

4. The mechanically damaged resistant twisted-pair unsheathed signal cable according to claim 1, characterized in that, The insulating layer is an ethylene-tetrafluoroethylene copolymer.

5. The mechanically damaged resistant twisted-pair unsheathed signal cable according to claim 1, characterized in that, The twist pitch of the twisted pair is 10 times the outer diameter of the twisted pair, and the twisted pair is twisted in the S direction.

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