Reduced screen braid

Abstract

The present invention relates to an electrical cable. One embodiment of the electrical cable 100 has at least one first conductor. The first conductor has a first electrical conductor 110. The first conductor further has insulation 120 surrounding the first electrical conductor 110. The electrical cable 100 has at least one first braided shield 140. The optical coverage of the first braided shield 140 is less than 80%. The electrical cable 100 further has a sheath 150. The sheath 150 completely surrounds the first braided shield 140.

Description

[0001] The present disclosure relates to an electrical line, in particular an electrical data line.

[0002] Electrical cables are used in a wide variety of fields. Examples of electrical cables include charging cables and data cables. Cables for transmitting data (or simply data cables) are used in a wide range of technical applications. A data cable is a medium for transmitting signals; that is, data is usually transmitted using signals as data signals. Transmission can be electrical (electrical data cable), optical (optical data cable), or a combination of both (usually called a hybrid cable, sometimes also a combination cable).

[0003] Electrical data cables typically have at least one core consisting of a conductor made of copper or an alloy material and a cylindrical sheath made of a plastic suitable for high frequencies. Electrical data cables also usually have a shielding foil and a wire shield to improve the shielding effect of the electrical data cable.

[0004] Shielded data cables are an essential component of the data cable portfolio in the automotive industry. The shield serves as a ground potential in the case of asymmetrical data transmissions and / or provides electromagnetic shielding from environmental influences. The degree of this shielding is characterized primarily by the shielding attenuation. A minimum level of shielding, and consequently a minimum level of shielding attenuation, is defined in the relevant OEM (Original Equipment Manufacturer) and cable standards.

[0005] All these standards are based on the assumption that a high optical coverage of a wire screen corresponds to a high shielding effect.

[0006] DE 199 14 924 A1, for example, describes a flexible high-voltage electrical cable consisting of a central core, power conductors stranded around the core, and at least one control line also stranded around the core.

[0007] The power lines have a flexible electrical conductor, over which insulation and a shield consisting of a braid of metallic wires are applied. Additionally, at least one data line is provided, surrounded by a braid of metallic wires serving as a shield with an optical coverage of at least 85%. The braid shielding of the power lines has an optical coverage of at least 80%. Both braids are applied with a shallow angle of inclination between 50° and 60°.

[0008] AT 523 921 B1 describes a coaxial cable for transmitting electric current in a high-voltage system of a motor vehicle, comprising an inner conductor, an outer conductor, and an insulating cable sheath, wherein the outer conductor is designed to transmit essentially the same electrical power as the inner conductor. A cable foil or a metal foil is arranged between the outer conductor and the cable sheath, wherein the optical coverage of the outer conductor is greater than 90%, preferably greater than 95%.

[0009] However, such electrical data cables are frequently used in mechanically demanding, dynamic installation situations, such as in a vehicle door. Electrical cables known from the prior art, with a high optical coverage of the wire shield, exhibit low flexibility with regard to bending, torsional, and tensile stresses in the longitudinal direction of the electrical cable due to the closely spaced wires of the wire shield.

[0010] Based on this, an improved electrical cable is to be provided. In particular, there is a need for an electrical cable with good shielding attenuation and the highest possible flexibility.

[0011] The problem is solved by the subject matter of the attached independent patent claim.

[0012] An electrical cable is provided. The electrical cable has at least one core. The core has at least one electrical conductor. The core also has insulation surrounding the at least one electrical conductor. The electrical cable has at least one braided shield. The optical coverage of the braided shield is less than 80%. The electrical cable also has a sheath. The sheath completely surrounds the braided shield.

[0013] Optical coverage here describes the proportion of the conductor's circumferential area that is covered by the first braided shield. High optical coverage generally reduces the flexibility of the conductor because the required bending force increases. This is primarily due to the fact that the wires of the braided shield are closer together and therefore have less freedom of movement than with lower optical coverage.

[0014] The first electrical conductor can be a solid conductor or a stranded conductor. For example, the first electrical conductor can be a solid copper conductor. Such a conductor has very good high-frequency properties, especially regarding attenuation. Alternatively, the first electrical conductor can be a stranded copper conductor, a solid alloy conductor, a solid copper-clad steel conductor (CCS), a solid copper-clad aluminum conductor (CCA), a stranded conductor made of CCS, a stranded conductor made of CCA, or a stranded conductor made of alloys. These conductors are more flexible than the previously mentioned solid copper conductor. The flexibility of the electrical conductor can be further increased depending on the alloy and / or strands used.The electrical conductor can be designed as a Class 5 or Class 6 conductor according to IEC 60228 to increase flexibility.

[0015] The insulation can be arranged / formed in a cylindrical shape around the first electrical conductor. In other words, the first electrical conductor can be provided with a cylindrical insulating layer. The insulating layer can have a plastic dielectric or be formed entirely from a plastic. The plastics used can be selected based on their high-frequency properties. For example, polyethylene (PE), polypropylene (PP), or fluoroethylene propylene (FEP) can be used in solid or multilayer configurations, either as solid or foamed layers. The choice between solid or foamed insulating materials can be made according to the specific mechanical requirements of the finished cable.

[0016] The electrical conductor can have at least one first shielding foil. In one variant, the first shielding foil can completely surround the first conductor. The first shielding foil can be applied directly to the first conductor. This allows the first shielding foil to hold the first conductor even when the electrical conductor is subjected to mechanical stresses or strains, such as bending or torsion. In another variant, the first shielding foil can completely surround the first braided shield. The first shielding foil can have an overlap of approximately 5% to approximately 55%, particularly approximately 20% to approximately 35%, in the circumferential direction.

[0017] An overlap area of ​​the first shielding foil offers the advantage that even under torsional or bending stress and a resulting movement of the first shielding foil, complete coverage of the inner at least one first conductor or the inner at least one first shielding braid by the first shielding foil is ensured.

[0018] The first shielding foil can have a first metal layer. The first metal layer can be located on the side of the first shielding foil facing the first conductor. The first metal layer can contain aluminum.

[0019] The first shielding foil may have a second metal layer. The second metal layer may contain aluminum. The second metal layer may be located on the side of the first shielding foil facing away from the first conductor. The first shielding foil may contain at least a portion of a plastic. The first shielding foil may contain polyethylene terephthalate (PET) or polypropylene (PP).

[0020] The formation of a laminated shielding foil with at least one metallic shielding layer applied to a plastic shielding layer offers the advantage of improved shielding effectiveness with a low layer thickness due to the different materials.

[0021] The first shielding foil can have a sliding layer on the side facing the first conductor. The first shielding foil can have a sliding layer on the side facing away from the first conductor.

[0022] Applying a sliding layer to the side of the shielding foil facing the first conductor and / or the side facing away from the first conductor reduces friction and thus wear of the shielding layer when in contact with the shielding braid, the first conductor and / or a part of the first shielding foil itself in the overlap area.

[0023] In one variant, the sliding layer can contain a fluoropolymer. This fluoropolymer can be a perfluoropolyether (PFPE) or polytetrafluoroethylene (PTFE). In another variant, the sliding layer can contain a siloxane polymer, a silicone oil, and / or a silicone grease. In yet another variant, the sliding layer can be a water-based sliding layer or comprise a water-based sliding layer.

[0024] The sliding layer can have a thickness of less than 50 µm, in particular less than 25 µm. The thickness of the sliding layer here refers specifically to its extent in the radial direction.

[0025] In one variant, the first braided shield can have an optical coverage of approximately 50% to approximately 75%. In another variant, the first braided shield can have an optical coverage of approximately 33% to approximately 55%. A low optical coverage significantly increases the flexibility of the electrical conductors. Conversely, an optical coverage below 33% leads to an excessive decrease in the braided shield's stability, preventing it from withstanding the bending, torsional, and tensile loads encountered in dynamic installation situations. This results in faster wear of the first braided shield and, consequently, of the electrical conductor.

[0026] In one variant, the first shielding braid can be applied directly to the first shielding foil. In another variant, the first shielding braid can be applied directly to the first conductor.

[0027] The first canopy braid can be constructed with plies. The first canopy braid can have 8 to 24 plies, in particular 16 plies.

[0028] The plies can each contain 2 to 5 wires. In one variant, the plies of the first shielding braid can each contain a different number of wires. In another variant, the plies of the first shielding braid can be identical. In another variant, the plies can each contain 5 wires. In another variant, the plies can each contain 4 wires. In another variant, the plies can each contain 3 wires. In another variant, the plies can each contain 2 wires.

[0029] The fewer wires per layer, the less material is required to manufacture the electrical cable, and consequently, the smaller its carbon footprint. Furthermore, reducing the number of wires per layer significantly reduces the cable's weight. Additionally, a lower number of wires per layer results in less visible coverage of the braided shield, thus increasing the cable's flexibility. However, constructing the first braided shield with individual wires and no layers can reduce its stability under bending, torsional, or tensile stresses to such an extent that it cannot be used in dynamic installation situations.

[0030] The wires can have a round cross-section with a diameter of approximately 0.07 mm to approximately 0.15 mm, in particular from approximately 0.094 mm to approximately 0.105 mm.

[0031] In one variant, one or more, for example all, of the wires can have a non-circular cross-sectional shape. In another variant, one or more, in particular all, of the wires can have an elliptical cross-sectional shape. The wires with non-circular or elliptical cross-sectional shapes can have a height of approximately 0.1 mm to approximately 0.2 mm. The wires with non-circular or elliptical cross-sectional shapes can have a width-to-height ratio of no more than 3:1.

[0032] The formation of wires with non-circular or elliptical cross-sectional shapes offers the particular advantage that, on the one hand, the material usage and the thickness of the shielding layer are reduced while maintaining the same optical coverage, and on the other hand, the durability of the shielding foil is increased by reducing the contact points of the layers.

[0033] Individual wires within a lattice can have a cross-sectional shape different from the other wires in the lattice. Individual lattices can contain wires with a cross-sectional shape different from the wires in the other lattices.

[0034] In one variant, the wires can contain tinned copper. In another variant, the wires can contain copper. In another variant, the wires can contain a copper alloy. In another variant, the wires can contain copper-clad steel (CCS). In another variant, the wires can contain copper-clad aluminum (CCA). In yet another variant, the wires can contain a composite material with one or more metallic components.

[0035] The wires can have a tensile strength of approximately 200 N / mm² to approximately 800 N / mm².

[0036] The wires may have an oil-coated surface. The laminations may have an oil-coated surface.

[0037] An oil-coated surface on the wires or the laminations reduces friction between the wires.

[0038] The first screen braid can still have a braid pitch of approximately 20 mm to approximately 80 mm, in particular 50 mm.

[0039] A braid pitch of less than approximately 20 mm would result in increased friction between the wires when the cable is torsioned. Conversely, a braid pitch of more than approximately 80 mm leads to a decrease in the mechanical stability of the first braided shield.

[0040] The first braided shield can have a shielding angle of approximately 50° to approximately 87°, particularly approximately 70° to approximately 85°, with respect to a cross-sectional area of ​​the electrical conductor. The first braided shield can also have a shielding angle of approximately 3° to approximately 40°, particularly approximately 5° to approximately 20°, with respect to a longitudinal axis of the electrical conductor.

[0041] A shield angle of approximately 50° to approximately 87° to the cross-sectional area of ​​the electrical conductor ensures, on the one hand, that the number of intersection points of the wires with each other in the longitudinal direction does not become too small and thus reduce the mechanical stability, and on the other hand, that the friction between the wires in the tangential direction does not increase under torsional stress.

[0042] The first braided shield can have a tensile strength of at least 70 N, in particular at least 110 N. The tensile strength defines the strength of the braided shield under a tensile force acting in the longitudinal direction of the electrical conductor.

[0043] The first braided shield can exhibit an elongation under tensile stress in the longitudinal direction of the electrical conductor of approximately 1.5% to approximately 2.3%.

[0044] In one variant, the physical dimensions of the electrical conductor can correspond to the physical dimensions of an RTK031 coaxial cable. In other words, the diameter of the first conductor, the diameter of the first braided shield, and the diameter of the jacket can correspond to the respective diameters of the conductor, braided shield, and jacket of an RTK031 coaxial cable.

[0045] The RTK031 coaxial cable, known from the prior art, has a braided shield with 16 layers, each containing 7 wires. The wires have a diameter of 0.1 mm, resulting in an optical coverage of approximately 91% of the braided shield. In a variant where the size of the electrical conductor corresponds to the size of the RTK031, the first braided shield with 16 layers uses a reduced number of wires, specifically 5 wires per layer, resulting in an optical coverage of approximately 75%. In a variant of the first braided shield with 16 layers, each containing 4 wires, the optical coverage is approximately 64%. In a variant of the first braided shield with 16 layers, each containing 3 wires, the optical coverage is approximately 51%. In a variant of the first braided shield with 16 layers, each containing 2 wires, the optical coverage is approximately 36%.

[0046] The shielding attenuation of the first braid depends primarily on the wavelength of the signal being transmitted and the size of the meshes within the braid. The meshes of the braid represent the points where no wires of the plies run and where the first braid does not cover the first conductor. Depending on the shielding angle and the number of plies in the first braid, the meshes typically have the shape of a square, a rectangle, or a parallelogram. The smaller the side lengths of the braid's meshes are compared to the wavelength of the signal being transmitted, the greater the shielding attenuation.

[0047] In a first braided shield with 16 layers of 5 wires each, with a wire diameter of 0.1 mm and a resulting optical coverage of approximately 75%, the edge lengths of the meshes are each 0.4 mm longer than the edge lengths of the meshes in an RTK031 coaxial cable with 16 layers of 7 wires each and an optical coverage of 91%. The wavelength of a signal to be transmitted with a frequency of, for example, 100 MHz is approximately 3 m. The change in the edge lengths of the meshes by 0.4 mm, relative to the wavelength of 3 m, is in the range of approximately 0.01% and thus represents a negligible change in the mesh size and therefore also in the shielding attenuation.

[0048] Therefore, reducing optical coverage offers the particular advantage of increasing flexibility while maintaining high shielding attenuation.

[0049] The sheath can be applied directly to or arranged on the first braided shield. Alternatively, a separating element or separating agent can be provided between the first braided shield and the sheath. In other words, the electrical conductor can have a separating element or separating agent that can be provided between the first braided shield and the sheath. Thus, a separating element or separating agent can be used between the first braided shield and the sheath as needed. The separating element can, for example, be in the form of a film or have a film component. The separating agent can, for example, be in powder form.

[0050] The shell can have a wall thickness that is at least nearly uniform or constant along its entire circumference. In other words, the shell can be designed or constructed with a uniform wall thickness across its entire circumference.

[0051] The sheath, and thus the electrical conductor, can have an outer diameter of approximately 2 mm to approximately 4 mm, in particular 3.3 mm. The first conductor can have a diameter of approximately 1.5 mm to approximately 3.5 mm, in particular approximately 2.1 mm. The first conductor can have a diameter of approximately 80%, in particular approximately 85%, of the outer diameter of the sheath.

[0052] The electrical cable may additionally have a second conductor. The second conductor may contain a second electrical conductor and a second layer of insulation surrounding the second electrical conductor.

[0053] The first conductor and the second conductor can each have separate insulation. In other words, the first insulation and the second insulation can be separate from each other. Alternatively, the first insulation and the second insulation can be formed by a common insulation. In other words, the first electrical conductor and the second electrical conductor can be surrounded by a common insulation.

[0054] Regardless of the precise design of the first and second insulation layers, the first and second conductors can form a conductor pair or be configured as a single conductor pair. The first and second conductors can run parallel to each other along the length of the electrical conductor. The first and second conductors can run parallel to each other along their entire length and / or along the entire length of the electrical conductor. The parallel arrangement of the first and second conductors can achieve (very) high torsional stability. The first and second conductors can be stranded together. Within the limits of technical feasibility, the two conductors can be manufactured to be at least nearly identical in their properties and / or dimensions.

[0055] The first shielding foil can completely surround the first and second conductors. In particular, the first shielding foil can be applied directly to the first and second conductors.

[0056] In one variant, the electrical conductor can have a multitude of conductors, in particular more than two conductors. The individual conductors of the multitude can each have separate insulation. The conductors of the multitude can be twisted together. The multitude of conductors can be completely surrounded by a common insulation.

[0057] The electrical conductor may have a second shielding foil. The second shielding foil may have an overlap of approximately 20% to approximately 55%, particularly approximately 20% to approximately 35% or approximately 50% to approximately 55%, in the direction of a circumference. The second shielding foil may include a metal layer. The second shielding foil may be designed as a metal layer.

[0058] The second shielding foil can be positioned between the first conductor and the first shielding foil. The second shielding foil can be positioned between the first shielding foil and the first shielding braid. The second shielding foil can be positioned between the first shielding braid and the casing.

[0059] The metal layer can be arranged on a radially inner side of the second shielding foil. The metal layer can be designed as an aluminum layer.

[0060] The second shielding foil can have an additional metal layer. This additional metal layer can be made of aluminum. The additional metal layer can be located on a radially outer side of the second shielding foil. The second shielding foil can contain at least a portion of a plastic. The second shielding foil can contain at least a portion of polyethylene terephthalate (PET) or polypropylene (PP).

[0061] The second shielding film can have a sliding layer on its radially inner side. The second shielding film can have a sliding layer on its radially outer side.

[0062] The electrical cable can have a second braided shield. The second braided shield can be located between the first braided shield and the outer jacket. The second braided shield can be located between the outer jacket and the first shielding foil. The second braided shield can be located between the outer jacket and the second shielding foil.

[0063] The second shielding braid can be identical in design to the first shielding braid. The second shielding braid can be constructed with wire reinforcements.

[0064] All the aforementioned characteristics relating to the first umbrella weave also apply accordingly to the second umbrella weave.

[0065] Further details, features, advantages, and effects of the electrical conductor described herein will become apparent from the following description of currently preferred variants and from the drawings. These show: Fig. 1a a schematic representation of a cross-section of the electrical conductor; Fig. 1b a schematic representation of a cross-section of the electrical conductor with a first shielding foil; Fig. 2a a schematic representation of a lattice with 4 wires; Fig. 2b a schematic representation of a lattice with 7 wires; Fig. 3a a schematic representation of a first variant of a screen film; Fig. 3b a schematic representation of a second variant of a screen film; Fig. 3c a schematic representation of a third variant of a screen film; Fig. 3d a schematic representation of a fourth variant of a screen film; Fig. 4 a schematic representation of the first screen mesh; Fig. 5a a schematic representation of an idealized first screen mesh with 16 layers; Fig. 5b a schematic representation of a mesh of the idealized first umbrella weave; Fig. 5c a schematic representation of a right-angled triangle of a mesh of a real umbrella mesh under tensile stress.

[0066] In Fig. 1a A schematic cross-section of an electrical line 100 according to a first embodiment is shown. The electrical line has a first conductor, which in turn has a first electrical conductor 110 and insulation 120 surrounding the first electrical conductor 110.

[0067] The electrical conductor 100 further comprises a first shield braid 140. The first shield braid 140 has 16 plies 141, each with four wires 142 per ply. The wires 142 have a round cross-section with a diameter of approximately 0.1 mm. The eight outermost plies 141 run around the first conductor in a first direction 45, and the innermost plies 141 run around the first conductor in a direction 46 opposite to the first direction. The 16 plies 141 are interwoven at intersection points 44, thus forming the first shield braid 140.

[0068] The Fig.1a Figure 1 shows a cross-section of the electrical conductor 100 at a random position along its length. The relative positions of the braids 141 vary due to their opposite orientation around the first conductor along the length of the electrical conductor 100 and repeat periodically depending on the braid pitch 42 and the shield angle 43.

[0069] The Fig. 1b Figure 1 schematically shows a cross-section of an electrical conductor 100 according to a second embodiment. In this embodiment, the electrical conductor 100 has, in addition to the features shown in Figure 1, the following features: Fig. 1a The features shown include a first shielding foil 130, wherein the shielding foil 130 has at least one metal layer 133 (in Figur 1b (not separately marked)

[0070] The first shielding foil 130 is positioned between the first conductor and the first braided shield 140 and completely surrounds the first conductor. The first shielding foil 130 is folded around the insulation 120 of the first conductor, creating an overlap area of ​​the first shielding foil 130. This overlap area comprises approximately 25% of the circumference of the insulation 120. The overlap area ensures that even under mechanical stress on the electrical conductor 100, such as torsion or bending, and thus in the event of possible displacement or deformation of the first shielding foil 130 relative to the first conductor, the first shielding foil 130 continues to completely enclose the first conductor.

[0071] In further embodiments, the first shielding foil 130 can be applied helically to the first conductor in a first lay direction, with the individual wraps of the first shielding foil 130 also having an overlap area. The width and pitch of the first shielding foil 130 can be selected accordingly. The first lay direction can be a so-called "S" lay direction (S-lay) or a "Z" lay direction (Z-lay).

[0072] The construction of the screen foil 130 in various exemplary design variants is described in the Fig. 3a bis 3d shown.

[0073] First, the Fig.2a und Fig. 2b a further advantage of reducing optical coverage in the event that the reduction of optical coverage is based on a reduction in the number of wires 142 per layer 141.

[0074] The Fig. 2a shows a lattice 141 with four wires 142 corresponding to the electrical line 100 of the Fig. 1a oder Fig. 1b . The Fig. 2b Figure 1 shows a layer 141 with seven wires 142, as is known, for example, from an RTK031 coaxial cable known from the prior art. The layers 141 are in direct contact with the first shielding foil 130.

[0075] Electrical cables are used not only in static installation situations but also in dynamically stressed installation situations, such as a tailgate or a vehicle door. The wires 141 of the shielding braid 140 are frequently subjected to increased force (bending, torsional, or tensile force), causing the wires 141 to move relative to the shielding foil 130 and rub against the foil 130 at their contact points 91. This leads to wear of the shielding foil 130 and thus to a reduction in the service life of the electrical cable 100.

[0076] By reducing the optical coverage of the first shield braid 140 by reducing the number of wires 142 per layer 141, the number of contact points 91 is simultaneously reduced. This consequently reduces the number of friction points and extends the service life of the electrical conductor 100 in dynamic installation situations.

[0077] The Fig. 3a bis Fig. 3d show exemplary embodiments of the first screen foil 130.

[0078] Fig. 3a Figure 1 shows a variant of the first shielding foil 130, which is designed as a double-sided laminated first shielding foil 130. The first shielding foil 130 has a core layer 132 made of a plastic, in particular polyethylene terephthalate (PET). On one side 136 of the core layer 132 facing the first conductor and thus radially inner, the first shielding foil 130 has a first metal layer 133 containing aluminum, on which a sliding layer 135 is applied. On one side 137 of the core layer 132 facing away from the first conductor and thus radially outer, the shielding foil 130 has a second metal layer 134 containing aluminum, which corresponds to the first metal layer 133 in its thickness and design. A sliding layer 135 is also applied to the second metal layer 134.The sliding layer 135 is made of a fluoropolymer and has a thickness of less than 25 µm. When the shielding layer 130 is arranged with an overlap area, the sliding layer reduces friction between the first metal layer 133 and the second metal layer 134 in the overlap area 131. Furthermore, it reduces the friction between the first metal layer 133 and the first conductor, and the friction between the second metal layer 134 and the first shielding braid 140. This significantly increases the service life of the first shielding foil 130 and thus the service life of the electrical conductor 100.

[0079] Fig. 3b Figure 1 shows a variant of the first shielding foil 130, which is designed as a single-sided laminated first shielding foil 130. The first shielding foil 130 has a core layer 132 made of a plastic, in particular polyethylene terephthalate (PET). On one side 136 of the core layer 132 facing the first conductor and thus radially inner, the first shielding foil 130 has a first metal layer 133 containing aluminum, on which a sliding layer 135 is applied. The sliding layer 135 thus forms the outermost layer on one side 136 of the first shielding foil 130 facing the first conductor. The core layer 132 forms the outermost layer on the side 137 of the first shielding foil 130 facing away from the first conductor.

[0080] Fig. 3c Figure 1 shows a variant of the first shielding foil 130, which has an aluminum-containing core layer 133. A sliding layer 135 is applied to one of the radially inner sides 136 of the core layer 133 facing the first conductor. A sliding layer 135 is also applied to one of the radially outer sides 137 of the core layer 133 facing away from the first conductor. The sliding layer 135 thus forms the outermost layer on both the sides 136 / 137 of the first shielding foil 130 facing the first conductor and those facing away from it.

[0081] Fig. 3d Figure 1 shows a variant of the first shielding foil 130, which is designed as a double-sided laminated first shielding foil 130. The first shielding foil 130 has a core layer 132 made of a plastic, in particular polyethylene terephthalate (PET). On one side 136 of the core layer 132 facing the first conductor and thus radially inner, the first shielding foil 130 has a first metal layer 133 containing aluminum, on which a sliding layer 135 is applied. On one side 137 of the core layer 132 facing away from the first conductor and thus radially outer, the shielding foil 130 has a second metal layer 134 containing aluminum, which corresponds in thickness and design to the first metal layer 133. The sliding layer 135 thus forms the outermost layer on one side 136 of the first shielding foil 130 facing the first conductor.The second metal layer 134 forms the outermost layer on one side 137 of the first shielding foil 130 facing away from the first conductor.

[0082] The Figuren 3a bis 3d The figures shown here are merely exemplary embodiments of the first shielding layer 130. Further embodiments of the first shielding layer 130 are conceivable.

[0083] The Fig.4 schematically shows a first shield braid 140 of the electrical conductor 100 according to the Fig. 1a und 1b .

[0084] The Fig. 4 To simplify the explanation, this shows that the entire area 41 is on the first screen sheet 130 ( Fig.1b ) or the first vein ( Fig.1a ) applied shielding mesh 140 in a two-dimensional plane.

[0085] For the sake of clarity, the following are in the Fig. 4 Only two plies 141 of the shielding mesh 140 are shown. The exemplary shielding mesh 140, as it appears in the Fig. 1a und Fig. 1b The example shown comprises a total of 16 compartments (141).

[0086] In the embodiment shown here, the plies 141 each comprise four wires 142. A first ply 141 shown here is wound around the first shield foil 130 or the first conductor with a first lay direction 45. Due to the representation of the braided shield 140 in a plane, the wires 142, as soon as they reach one side of the plane, begin on the opposite side of the plane, as indicated by the dashed wire 142.

[0087] A second layer 141 is wrapped around the first shielding foil 130 or the first conductor with a laying direction 46 opposite to that of the first layer 45. At the intersection points 44 of the two layers 141, they are interwoven, forming the shielding braid 140.

[0088] Each layer 141 with the first lay direction 45 can alternately cross over and under a layer 141 with the opposite lay direction 46 in the direction of extension, i.e., in the longitudinal direction of the cable. Similarly, each layer 141 with the opposite lay direction 46 can alternately cross over and under a layer 141 with the first lay direction 45 in the direction of extension.

[0089] Alternatively, each layer 141 with the first beat direction 45 can alternately cross two layers 141 with the opposite beat direction 46 in the direction of extension, and then undercross two layers 141 with the opposite beat direction 46. Similarly, each layer 141 with the opposite beat direction 46 can alternately cross two layers 141 with the first beat direction 45 in the direction of extension, and then undercross two layers 141 with the first beat direction 45.

[0090] As an alternative to interlacing the plies, the two plies can also be wound together. More precisely, a first ply 141 could be wound around the first shielding foil 130 or the first conductor in a first lay direction 45, and a second ply 141 could be wound around the first shielding foil 130 or the first conductor and onto the first ply 141 in a second lay direction 46.

[0091] The two illustrated exemplary plies 141 are wound around the first shielding foil 130 or the first conductor with a lay length / braid pitch 42 of approximately 50 mm. The plies 141 are further wound around the first shielding foil 130 or the first conductor with a shielding angle 43 of 70° to 85° to a cross-sectional area of ​​the electrical conductor 100. The cross-sectional area is shown in the Fig. 4 The illustrated embodiment is not explicitly shown due to its representation in a two-dimensional plane. The screen angle 43 is represented here analogously to the cross-sectional area in a three-dimensional representation, corresponding to the side of the two-dimensional plane that represents the entire circumference 41.

[0092] The Fig.5a bis Fig. 5c show a further advantage of reducing optical coverage in the case that the reduction of optical coverage is based on a reduction in the number of wires 142 per layer 141.

[0093] Fig. 5a Figure 1 schematically shows the first shielding braid 140 with 16 plies 141, wherein 8 plies 141 are wound in a first lay direction 45 and 8 plies are wound in a second lay direction 46 opposite to the first lay direction 45. The plies are interwoven at the intersection points 44. The plies 141 form meshes 50 in the first shielding braid 140, in which no plies 141 run. The size of these meshes 50 determines, on the one hand, the degree of optical coverage of the first shielding braid 140 and, on the other hand, the extensibility of the first shielding braid 140 under a tensile load in a longitudinal direction L of the electrical conductor 100.

[0094] In Fig. 5b is a mesh 50 of the first umbrella weave 140 with 16 plies 141 after Fig. 5a shown. Mesh 50 has the shape of a parallelogram and can be divided into four congruent right-angled triangles, each with a first leg 51 and a second leg 52. A segment of the lattices 141 between two intersection points 44 forms the hypotenuse 53 of the right-angled triangle. Since the lattices 141 are tightly interwoven at the intersection points 44, the hypotenuse 53 of the right-angled triangles is always constant.

[0095] The Fig. 5a und 5b Here, we show an idealized structure of a first shielding braid 140 with almost infinitely thin plies 141, such that when a tensile load is applied in a longitudinal direction L of the electrical conductor 100, the mesh 50 is stretched in the longitudinal direction L and compressed in a transverse direction Q such that the length of the first leg 51 is zero and the length of the second leg 52 corresponds to the length of the hypotenuse 53. In other words, in this idealized first shielding braid 140, when a tensile load is applied, all plies 141 run along the second leg 52 and thus almost parallel to each other.

[0096] The Fig.5c schematically shows a right-angled triangle of a mesh 50 of a first shield braid 140 of an electrical conductor 100 according to Fig. 1a oder 1b with a real setup, as it appears in simplified form in Fig. 4 The bay 141 has four wires 142, a bay width 143 and a central axis 53, which simultaneously represents the hypotenuse of the right-angled triangle.

[0097] The second leg 52 runs in the longitudinal direction L of the electrical conductor 100. The first leg 51 runs in a transverse direction Q perpendicular to the longitudinal direction L and thus along the circumference 41 of the electrical conductor 100.

[0098] When a tensile load acts on the first shield braid 140 in the longitudinal direction L of the electrical conductor 100, the plies 141 in the shield braid 140 are initially displaced before the tensile load acts directly on the wires 142. In particular, the mesh 50 and thus also the right-angled triangle, analogous to that in Fig. 5b In the idealized embodiment shown, the mesh is stretched in the longitudinal direction L and compressed in the transverse direction Q. However, due to the mesh width 143, which in a real construction of the meshes 141 corresponds to the number of wires 142 multiplied by their diameter, the mesh 50 cannot be stretched in the longitudinal direction L such that the length of the second leg 52 corresponds to the length of the hypotenuse 53.

[0099] In the first shield mesh 140 with the actual construction, the first leg 51 defines the length from a center point 56 of the mesh 50 to a point 55 of the central axis 53 of the ply 141. The second leg 52 defines the length from the center point 56 of the mesh 50 to a point 54 of the central axis 53 of the ply 141.

[0100] The Fig.5c Figure 1 shows the mesh 141 before a tensile load and the same mesh 141 as mesh 141' under an applied tensile load in the longitudinal direction L. Under tensile load, point 54 of the central axis 53 of mesh 141 shifts to point 54'. In other words, mesh 50 is stretched in the longitudinal direction L. Simultaneously, point 55 of the central axis 53 of mesh 141 shifts to point 55'. In other words, mesh 50 is compressed in the transverse direction Q.

[0101] The maximum positional displacement of the lattice 141 towards the position of the lattice 141' shown here, before the tensile forces act on the wires 142 of the lattice, is reached when the length of the first legs 51' corresponds to half the lattice width 143.

[0102] The greater the ply width 143, the longer the first leg 51' and the shorter the second leg 52' under tensile stress and maximum positional displacement. In particular, the length of the second leg 52' compared to the length of the second leg 52 without tensile stress defines the extensibility of the first shield braid 140 before the tensile stress acts on the wires 142 themselves.

[0103] In a previously known RTK032 coaxial cable with a braided shield consisting of 16 layers, each with 7 wires of 0.1 mm diameter, a shield foil circumference of 6.6 mm, and a braid pitch of 30 mm, the elongation of the braided shield is 0.7%. In other words, the second leg 52' is 0.7% longer under tensile stress than the second leg 52 without tensile stress.

[0104] By reducing the optical coverage through a reduction in the number of wires 142 per layer 141, this elasticity is significantly increased. For an electrical conductor 100 according to Fig.1a und Fig. 1b , whose dimensions correspond to those of an RTK032 coaxial cable, with a first braided shield 140 having 16 plies and 4 wires 142 per ply 141, where the wires 142 have a diameter of 0.1 mm, the elongation due to the reduced ply width 143 is approximately 1.8%. This corresponds to an increase in elongation of 150% compared to an RTK031 coaxial cable of the same dimensions.

[0105] Reducing the number of wires 142 per layer 141 to two wires 142 increases the elongation to approximately 2.3%, which corresponds to an increase in elongation of more than 200%.

[0106] The previously described variants of the electrical conductor, including their construction and operational aspects, serve only to enhance understanding of the structure, function, and properties; they do not limit the disclosure to these exemplary embodiments. Some of the figures are schematic. In some cases, essential properties and effects are shown significantly enlarged to clarify the functions, operating principles, technical configurations, and features. Each function, principle, technical configuration, and feature disclosed in the figures or text can be freely and arbitrarily combined with all claims, features in the text and in other figures, functions, principles, technical configurations, and features contained in or arising from this disclosure, so that all conceivable combinations can be attributed to the described procedure.This includes combinations of all individual descriptions in the text, that is, in every section of the description, in the claims, and also combinations of different variants in the text, in the claims, and in the figures. The claims do not limit the disclosure and thus the possible combinations of all the identified features with one another. All disclosed features are explicitly disclosed here, both individually and in combination with all other features.

Claims

1. An electrical conductor (100) comprising: - at least one first conductor, wherein the at least one first conductor comprises at least one first electrical conductor (110) and insulation (120) surrounding the at least first electrical conductor (110); - at least one first braided shield (140), wherein the optical coverage of the first braided shield (140) is less than 80%; and - a sheath (150) circumferentially surrounding the first braided shield (140).

2. The electrical conductor (100) according to claim 1, further comprising at least a first shielding foil (130), wherein the first shielding foil (130) has at least a first metal layer (133); and / or has an overlap area of ​​about 5% to about 55%, in particular about 20% to about 35%, in the circumferential direction.

3. The electrical conductor (100) according to claim 2, wherein the first metal layer (133) is arranged on one of the sides (136) of the first shielding foil (130) facing the first conductor; and / or is designed to contain aluminium.

4. The electrical conductor (100) according to one of claims 2 or 3, wherein the first shielding foil (130) has a second metal layer (134) arranged on a side (137) facing away from one of the first conductors, wherein the second metal layer (134) is configured to contain aluminium; and / or is configured to contain at least a portion of a plastic, in particular polyethylene terephthalate, PET.

5. The electrical conductor (100) according to one of claims 2 to 4, wherein the first shielding foil (130) has a sliding layer (135) on the side (136) facing the first conductor and / or on the side (137) facing away from the first conductor.

6. The electrical conductor (100) according to claim 5, wherein the sliding layer (135) contains a fluoropolymer, a siloxane polymer, a silicone oil and / or a silicone grease and / or is designed as a water-based sliding layer or has a water-based sliding layer.

7. The electrical conductor (100) according to one of the preceding claims, wherein the first shielding braid (140) has an optical coverage of about 50% to about 75%; or has an optical coverage of about 33% to about 55%.

8. The electrical conductor (100) according to one of the preceding claims, wherein the first shield braid (140) is formed with plies (141) each having 2 to 5 wires (142); and / or is formed with 16 plies.

9. The electrical conductor (100) according to claim 8, wherein the wires (142) are formed comprising tinned copper or copper or copper-clad aluminum or a copper alloy or CCS; and / or have a round cross-section with a diameter of about 0.07 mm to about 0.15 mm, in particular about 0.094 mm to 0.105 mm.

10. The electrical conductor (100) according to one of the preceding claims, wherein the first shield braid (140) has a braid pitch (42) of about 20 mm to about 80 mm, in particular 50 mm; and / or has a shield angle (43) of about 50° to about 87°, in particular about 70° to about 85°, to a cross-sectional area of ​​the electrical conductor (100); and / or has a tensile strength of at least 70 N, in particular at least 110 N.

11. The electrical conductor (100) according to one of the preceding claims, wherein the first shield braid (140) has an elongation under a tensile load in the longitudinal direction (L) of the electrical conductor (100) of about 1.5% to about 2.3%.

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