A stretch-resistant, signal-attenuation-resistant miniature coaxial cable
By combining a multi-strand silver-plated copper core conductor, an acrylate-based dielectric elastomer insulation layer, a vacuum-plated aluminized polyimide inner shielding layer, and a Vectran fiber reinforcement layer, the problems of easy deformation of the shielding layer and signal attenuation under dynamic mechanical action are solved, achieving stable signal transmission and flexibility.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGZHOU CABLE FACTORY CO LTD
- Filing Date
- 2025-06-09
- Publication Date
- 2026-06-05
AI Technical Summary
Existing cables are prone to deformation under tension, bending, or motion. Uneven stress distribution in the shielding layer leads to signal attenuation, and the increased structural rigidity makes it difficult to meet flexibility requirements.
It adopts a combination structure of multi-strand silver-plated copper core conductor, acrylate-based dielectric elastomer insulation layer, vacuum-plated aluminized polyimide inner shielding layer, Vectran fiber reinforcement layer and silver-plated copper wire braided outer shielding layer. The reinforcement layer is reinforced by alternating 30°/60° spiral winding to maintain the stability of the shielding layer and signal integrity.
It maintains the shielding layer's shape during stretching and bending, reduces signal attenuation, improves signal transmission efficiency and cable flexibility, and adapts to extreme temperature environments.
Smart Images
Figure CN224328515U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a miniature coaxial cable that is resistant to tensile stress and prevents signal attenuation, belonging to the field of cable technology. Background Technology
[0002] In fields such as high-precision mat systems, 5G communications, and medical devices, cables often need to operate stably for extended periods under stress, bending, or motion while maintaining good electrical performance and signal integrity.
[0003] In existing technologies, cables typically consist of a center conductor, an insulator, a metallic shield, and a sheath. In static environments, these cables can effectively transmit high-frequency signals and possess a certain degree of electromagnetic interference resistance. However, in practical applications, especially when cables are frequently subjected to dynamic mechanical forces such as tension, bending, and vibration, their internal structure is prone to deformation. In particular, the shield is susceptible to uneven stress distribution during tension, leading to loosening, breakage, or structural displacement of the braided mesh, resulting in impedance discontinuities and signal attenuation. Furthermore, the reinforcing layers designed to improve mechanical strength often uniformly cover the conductor, increasing the overall rigidity of the cable structure and making it difficult to meet flexibility requirements.
[0004] Therefore, there is an urgent need to develop a miniature coaxial cable that is resistant to tension and signal attenuation, which can solve the problems of easy deformation of the cable's shielding structure, high structural rigidity, and unstable signal when stretched. Utility Model Content
[0005] The technical problem to be solved by this utility model is to provide a miniature coaxial cable that is resistant to tension and prevents signal attenuation. It solves the problems of easy deformation of the cable's shielding structure, high structural rigidity, and unstable signal when stretched.
[0006] The technical problem to be solved by this utility model is achieved by the following technical solution: a miniature coaxial cable with tensile strength and signal attenuation resistance, comprising,
[0007] Conductor, insulating layer, inner shielding layer, outer shielding layer, sheath layer,
[0008] The conductor is provided with, in sequence, an insulating layer, an inner shielding layer, an outer shielding layer, and a sheathing layer.
[0009] The conductor comprises multiple strands of silver-plated copper cores, which are made by stranding. The insulating layer comprises an acrylate-based dielectric elastomer. The inner shielding layer comprises a vacuum-metallized polyimide film. A reinforcing layer is provided between the inner shielding layer and the outer shielding layer. The reinforcing layer comprises Vectran fibers. The outer shielding layer is woven from multiple silver-plated copper wires.
[0010] Preferably, the conductor is made of seven silver-plated copper cores, which are twisted together.
[0011] Preferably, the dielectric constant of the insulating layer is 2.8, the volume expansion rate is ≤5%, and the dielectric constant change rate is ≤2%.
[0012] Preferably, the thickness of the inner shielding layer is 7-9 μm, and the overlap rate is 10%.
[0013] Preferably, the outer shielding layer is woven from sixty-four silver-plated copper wires with a weaving density of 200 mesh and a single wire DC resistance of <0.8 Ω / m.
[0014] Preferably, the reinforcing layer is made by alternating spiral winding in 30° and 60° directions.
[0015] The beneficial effects of this utility model are:
[0016] This invention utilizes a reinforcing layer between the inner and outer shielding layers. During cable stretching, the shielding layer is prone to deformation, leading to sudden impedance changes. The reinforcing layer employs a rigid covering, achieved through alternating 30° / 60° winding, to maintain the shielding layer's stability during ≥30% stretching. The insulation layer uses an acrylic-based dielectric elastomer, which provides high elasticity to buffer tensile and bending stresses, preventing cracking or drastic changes in dielectric parameters during stretching and bending. It also maintains stable dielectric constant and dimensions, ensuring continuous impedance.
[0017] This invention utilizes a multi-strand silver-plated copper core as the conductor. Traditional single-strand copper wire suffers from high-frequency skin effect loss, signal attenuation, and high resistance. By using a multi-strand silver-plated copper core as the conductor, DC and high-frequency losses can be reduced, signal transmission efficiency and integrity can be improved, and attenuation can be reduced.
[0018] This invention utilizes a vacuum-metallized polyimide film as the shielding layer, which offers high shielding strength and is suitable for extreme temperatures. The outer shielding layer is woven from 64 silver-plated copper wires in a 200mm diameter, ensuring stable weaving density and preventing loss of dynamic shielding. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of this utility model.
[0020] In the diagram: 1-Conductor, 2-Insulation layer, 3-Inner shielding layer, 4-Reinforcing layer, 5-Outer shielding layer, 6-Sheath layer. Detailed Implementation
[0021] In order to make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments. Example 1
[0022] like Figure 1 As shown, a miniature coaxial cable with tensile strength and signal attenuation resistance includes a conductor 1, an insulation layer 2, an inner shielding layer 3, an outer shielding layer 5, and a sheath layer 6. The insulation layer 2, the inner shielding layer 3, the outer shielding layer 5, and the sheath layer 6 are arranged sequentially on the outer side of the conductor 1.
[0023] Conductor 1 is located at the center of the cable. A single strand of conductor 1 forms a cylindrical copper wire, and conductor 1 is made of multi-strand silver-plated copper wire. In this embodiment, seven strands of silver-plated copper wire are used, twisted together. Silver is uniformly plated onto the surface of the copper wire, with a silver layer thickness of approximately 0.5–1 μm. The silver layer improves the conductor's conductivity and provides good resistance to oxidation and corrosion, extending the conductor's service life.
[0024] An insulating layer 2 is disposed on the outer side of conductor 1. The insulating layer 2 has a certain buffering capacity. In this embodiment, the insulating layer 2 is annularly disposed on the surface of conductor 1 with the same axis as conductor 1. The insulating layer 2 is an acrylate-based dielectric elastomer with a dielectric constant of 2.6–3.0. In this embodiment, a dielectric constant of 2.8 is used. In terms of electrical insulation, the insulating layer 2 has a dielectric strength of 20–50 kV / mm, which can prevent breakdown; tanδ < 0.01 @10 GHz, ensuring low attenuation of high-frequency signals; it has a certain elasticity (elongation at break > 500%), absorbing tensile and bending stress and protecting the inner structure; the volume expansion rate is ≤ 5%, and the dielectric constant change rate is ≤ 2%.
[0025] An inner shielding layer 3 is provided on the outside of the insulation layer 2. The inner shielding layer 3 is made of vacuum-plated aluminized polyimide film with a thickness of 8μm. It is bonded along the cable axis with a bonding overlap rate of 10%. It has good DAINI shielding effectiveness, with a shielding effectiveness (SE) of >60 dB in the frequency range of 10 MHz to 10 GHz, effectively suppressing electromagnetic interference (EMI) and radio frequency interference (RFI). Dual shielding mechanism: the aluminum coating provides conductive shielding (reflection loss), and the polyimide substrate absorbs residual electromagnetic waves (absorption loss), improving the overall shielding efficiency by more than 30%. Good extreme temperature adaptability, with a long-term operating temperature of -269℃ to +260℃ (short-term resistance to 400℃), suitable for high-temperature scenarios such as spacecraft cables and engine compartments. It maintains flexibility in liquid nitrogen environment (-196℃) without the risk of brittleness. 3. Lightweight and high mechanical strength. The thickness can be controlled between 12 and 50 μm (traditional aluminum foil shielding layers require ≥100 μm), reducing the cable weight by 30% to 50%. The tensile strength of aluminized polyimide is >200 MPa (compared to only 50~80 MPa for ordinary aluminum foil), and its bending fatigue life is >100,000 cycles.
[0026] A reinforcing layer 4 is provided at the gap between the inner shielding layer 3 and the outer shielding layer. The reinforcing layer 4 is made of Vectran fiber. In this embodiment, the Vectran fiber is in the form of a strip, which is spirally wound alternately at 30° (tensile direction) and 60° (compression direction) to form an asymmetric mechanical support.
[0027] The reinforcing layer 4 can dynamically match the outer shielding layer 5. When stretched, the reinforcing layer 4 can extend to maintain a stable braiding density and shielding effectiveness (attenuation ≤0.5dB / m at 1GHz).
[0028] The reinforcing layer 4 is directly attached to the outside of the inner shielding layer, which can effectively constrain the lateral expansion of the inner structure (conductor + insulation + inner shielding); the braiding angle of the outer shielding layer 5 is aligned with the 30° winding area of the reinforcing layer 4, and the two extend together when stretched, avoiding the outer shielding layer 5 from breaking due to local stress concentration.
[0029] An outer shielding layer 5 is provided outside the reinforcing layer 4. The outer shielding layer 5 is a cylindrical braided mesh formed by 64 silver-plated copper wires (0.02 mm in diameter) woven at a 200-mesh density and attached to the outside of the reinforcing layer 4. The outer sides of the copper wires forming the outer shielding layer 5 are also silver-plated. By using the outer shielding layer 5, the 200-mesh braid density provides a broadband shielding effectiveness of >80 dB, suppressing external interference and internal crosstalk. The tensile strength of a single wire is >300 MPa, and the overall tensile strength of the braided structure is >12 N, far exceeding that of ordinary single-strand copper wire (approximately 5 N).
[0030] In this embodiment, a sheath layer 6 is provided on the outside of the outer shielding layer 5, and the sheath layer 6 is made of polyurethane. The sheath layer 6 can provide a certain degree of mechanical protection and environmental protection, preventing the cable from being damaged by factors such as scratches, abrasions, oil stains, and chemical corrosion.
[0031] In another embodiment, the outer shielding layer 5 does not have a sheath layer 6 on its outer side; in this case, the outer shielding layer 5 serves as the outermost layer of the cable. This is mainly used in locations where there are fewer factors that could damage the cable, such as scratches, abrasions, oil stains, or chemical corrosion.
[0032] In this embodiment, each layer is coaxially arranged along the center line and tightly bonded to reduce gaps between layers. The reinforcing layer 4 is directly wound around the outside of the inner membrane without any additional adhesive material between it and the membrane, relying on the spiral tension to hold it together. During the stretching process, the reinforcing layer 4 actively transfers stress to the outer shielding layer 5, causing it to extend synchronously and ensuring a constant weaving density. The insulating layer 2 can absorb stress in all directions, maintaining the geometric and electrical stability of the inner and outer shielding layers. In this embodiment, the overall structure maintains a characteristic impedance of 50±2 Ω under any stretching and bending conditions, and the attenuation at 1 GHz is ≤0.5 dB / m.
[0033] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of this utility model. All such changes and modifications fall within the scope of protection claimed by this utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. A miniature coaxial cable resistant to tensile stress and signal attenuation, comprising: Conductor, insulating layer, inner shielding layer, outer shielding layer, sheath layer, The conductor is provided with, in sequence, an insulating layer, an inner shielding layer, an outer shielding layer, and a sheathing layer. Its features are: The conductor comprises multiple strands of silver-plated copper cores, which are made by stranding. The insulating layer comprises an acrylate-based dielectric elastomer. The inner shielding layer comprises a vacuum-metallized polyimide film. A reinforcing layer is provided between the inner shielding layer and the outer shielding layer. The reinforcing layer comprises Vectran fibers. The outer shielding layer is woven from multiple silver-plated copper wires.
2. The miniature coaxial cable with tensile strength and signal attenuation resistance according to claim 1, characterized in that: The conductor is made of seven silver-plated copper cores, which are twisted together.
3. The miniature coaxial cable with tensile strength and signal attenuation protection according to claim 1, characterized in that: The dielectric constant of the insulating layer is 2.6-3.0, the volume expansion rate is ≤5%, and the dielectric constant change rate is ≤2%.
4. A miniature coaxial cable with tensile strength and signal attenuation protection according to claim 1, characterized in that: The thickness of the inner shielding layer is 7-9 μm, and the overlap rate is 10%.
5. A miniature coaxial cable with tensile strength and signal attenuation protection according to claim 1, characterized in that: The outer shielding layer is woven from sixty-four silver-plated copper wires with a weaving density of 200 mesh and a single wire DC resistance of <0.8 Ω / m.
6. A miniature coaxial cable with tensile strength and signal attenuation protection according to claim 1, characterized in that: The reinforcing layer is made by alternating spiral winding in 30° and 60° directions.