EP0828259A2 - Data cable and manufacturing method of data cables - Google Patents

Abstract

The data transmission cable four twisted pair data lines Ä4-7Ü that are embedded within a stable flexible plastic Ä8Ü that ensures that the relative position of the lines remains unchanged. The cable is completed by a screening layer Ä3Ü and an insulating layer Ä2Ü.Each of the data cores has a twisted pair of wires Ä17,18Ü set into a sleeve Ä9Ü of plastic, eg polyethylene, together with an outer layer of screening material. The arrangement provides an impedance that gives an attenuation of 17db at a frequency of 100MHz.

Description

The invention relates to data cables with at least one Double line and method for manufacturing such data cables.

There are many ways to transmit messages or data Multi-conductor cable, i.e. Cable with several or many conductors or veins, application. A pair of conductors or cores forms usually one line, a so-called double line. There are partial capacities and between the double lines -Inductors present that are an undesirable coupling between the circuits formed with the double lines, the so-called crosstalk. The The direct consequence of the crosstalk couplings are in operation Near and far crosstalk disorders, so-called NEXT (near end crosstalk) and FEXT (far end crosstalk) disorders. The near crosstalk disorder occurs at the same end of the Cable system on which the interferer is also located, while distant crosstalk disturbances and disturbers located at different ends of the cable system.

The twisting (also called stranding) of single wires to wire pairs offers the possibility of different cables decouple more or less well and thus keeping the crosstalk small. Therefore they are Wire pairs of a multi-conductor cable usually twisted.

Another way of decoupling double lines to achieve is to use the double lines to provide a shield. Are in the prior art therefore known double lines, consisting of two with each other twisted single wires exist, which in turn are direct are surrounded by a conductive shield. In doing so In the case of known cables, metal foils that directly isolate the wires surrounded by two single wires, the leading one Shielding.

Between the single wires and the conductive shield capacities are formed, which are the electrical properties significantly influence the cable, in particular the impedance and the damping properties of the Cable. The developing capacities - on the one hand directly between two single wires of a double line, on the other between single wires and shielding and thus also indirectly between two single wires via the shield - are determined by the distances between single wires and Shielding largely determined.

The geometry of the arrangement of cores and shielding determines ultimately both the impedance and the damping properties of the cable. Cause changes in geometry therefore inevitably changes in electrical properties, especially transmission properties of the data cable. Such cables are therefore very sensitive against external, mechanical influences. So change known ones Data cables for example their electrical properties, if you put a heavy object on it or when driving over with a vehicle. Also change their properties when bending, for example when Lay the cable in corners.

As already mentioned above, the distance of the Conductor for shielding the electrical properties, especially the impedance. It is therefore necessary to get one to achieve certain impedance, a certain minimum distance between conductor and shield. At well-known double cables with directly on the wire insulation Shielding on top determines the thickness of the wire insulation the distance between the conductor and the shield. thats why when choosing the thickness of the wire insulation to meet the requirements tied to impedance.

With conventional cables, for example so-called AWG-22 cables, the wire diameter is 1.6 mm for a wire diameter of approximately 0.64 mm. These cables have one Impedance of 100 ohms. A shield surrounds each pair of wires. A wire diameter of 1.6 mm is disadvantageous because these veins are not without limitation with conventional ones Have the connector systems contacted. Many conventional ones Connector connections are namely insulation displacement connections trained only veins with a maximum Can accommodate a diameter of 1.4 mm. The relatively thick However, wire insulation is necessary to achieve the desired impedance to achieve. The core diameter can therefore not be simply reduce.

With these known cables with one on each wire pair overlying shield is used to manufacture the relatively thick core insulation a high degree of foaming. However, a high degree of foaming Consequence that the veins are not particularly stable and therefore mechanical are very susceptible or sensitive.

A cable with a different geometry, a so-called star quad, is known from EP 0 567 757 A2.

The invention aims to be one in terms of transmission properties as well as the manageability To provide data cables.

a) ein Aderpaar bestehend aus zwei miteinander verdrallten Einzeladern, die jeweils einen Leiter und einen den Leiter umschließende Aderisolierung aufweisen,

b) einen das Aderpaar umgebenden Zwischenmantel und

c) eine den Zwischenmantel umgebende Abschirmung,

d) wobei der Zwischenmantel Einkerbungen zwischen den Oberflächen der Einzeladern des Aderpaares wenigstens teilweise ausfüllt, so daß er die Geometrie der Doppelleitung fixiert.

The invention achieves this aim by the subject matter according to claim 1, that is to say by a data cable with at least one double line, which comprises:

a) a wire pair consisting of two twisted single wires, each having a wire and a wire insulation surrounding the wire,

b) an intermediate sheath surrounding the pair of wires and

c) a shield surrounding the intermediate sheath,

d) wherein the intermediate sheath at least partially fills notches between the surfaces of the individual wires of the pair of wires, so that it fixes the geometry of the double line.

a) Verdrallen von zwei Einzeladern, die jeweils einen Leiter und eine den Leiter umschließende Aderisolierung aufweisen, zu einem Aderpaar;

b) Umgeben des Aderpaars mit einem Zwischenmantel, der Einkerbungen zwischen den Oberflächen der Einzeladern des Aderpaares wenigstens teilweise ausfüllt, so daß er die Geometrie der Doppelleitung fixiert und

c) Umgeben des Zwischenmantels mit einer Abschirmung.

The invention further achieves the aim by a method for producing a data cable with at least one double line, the production of the double line comprising the following steps:

a) twisting of two individual wires, each having a conductor and a wire insulation surrounding the conductor, to form a pair of wires;

b) Surrounding the wire pair with an intermediate sheath, which at least partially fills notches between the surfaces of the individual wires of the wire pair, so that it fixes the geometry of the double line and

c) Surrounding the intermediate sheath with a shield.

The data cable according to the invention therefore sees one of these trained intermediate jacket made of insulating material, e.g. Polyethylene before, the cavities, i.e. Notches between surfaces of adjacent single wires, at least partially filled. This ensures that the position of the single wires to each other, and thus the Geometry of stranding, even with extreme mechanical Load remains stable. The intermediate coat ensures therefore that the single wires of the data cable according to the invention a defined position to each other over the entire cable length have. This leads in particular to data transmission over long distances to a significant improvement. For example, the operating capacity of a pair of conductors carrying an electromagnetic wave i.a. due to the geometrical arrangement of the individual conductors determined in the cable core. Even the inductance the cable depends on the magnetic field outside the individual conductors and is therefore also determined by the distance between the individual conductors determined to each other. Both sizes - capacity and Inductance - significantly influence the resistance, Crosstalk and attenuation behavior of a cable. At the Data cables according to the invention have these sizes over the entire length of the cable a defined value. this will achieved by the position-stabilizing intermediate jacket, the ensures that the position of the single conductors or single wires is the same at all points of the cable.

The stabilization of the relative position of the single wires to each other has a very favorable effect on the so-called crosstalk behavior off, i.e. unwanted electromagnetic interference Energy from one double line to another. The crosstalk, especially between symmetrical ones Cables, among other things through capacitive and inductive couplings caused on asymmetries in the electrical Field and asymmetries in the geometric structure of the cable are due. Especially the asymmetries in the geometic According to the invention, the structure can be fixed minimize the individual wires relative to each other. Furthermore remains the crosstalk behavior due to the stabilization of the position over the entire cable length even with external mechanical Action constant.

The intermediate jacket is not only used for stabilization the relative position of the individual wires to each other, but also the stabilization of the shield surrounding the intermediate sheath with regard to their position to the single cores or their leaders. A stabilization of the shielding position to the conductors is advantageous because the distance of the Shielding to the conductors is decisive in the electrical Properties of the cable determined. Therefore it comes down to one exactly defined position of the shield in relation to the Head on. Because of its property as a dielectric (with a much higher dielectric constant than air) in that formed by wire pairs and capacitor The intermediate sheath reduces the capacitor Attenuation of the double line.

With a conventional data cable, in which the shielding without intermediate sheath on the individual wires form Voids between the shield and the single wires. This means that the distance between wire insulation and shielding varies. This results in an uneven Contact of shielding and wire insulation. By ordering an intermediate sheath according to the invention and a pair of wires around, you get a very even surface on which you can apply the shield. The shield encloses therefore very precise and defines the intermediate coat.

On the one hand, the intermediate jacket leads to precisely defined ones Geometry conditions of the single wires or their conductors in terms of shielding and that over the whole Cable length. On the other hand, the intermediate jacket avoids voids between wire insulation and shielding and reached thus even with mechanical stress on the cable, such as bending, a stabilization of the position of the Shielding in relation to the wire pair. A shift shielding against the wires is therefore virtually impossible.

Finally, the intermediate jacket serves to protect against penetration of moisture and mechanical damage to the Single cores.

Overall, the data cable according to the invention has an essential feature improved transmission properties (attenuation, crosstalk) up to very high frequencies in the range from to to 1000 MHz and larger and is also in its mechanical properties (stability even in curves, Kick and run resistance) very advantageous.

The procedure for manufacturing the cable is as follows: First you twist two single wires together. This can then be pulled through a wax bath so that the enveloping layers later lighter from the veins let separate. Then the intermediate coat on the Wire pair applied. This application is preferably done by extruding. As soon as the intermediate coat that A pair of wires surrounds a shield on the intermediate sheath upset.

In a preferred embodiment of the invention The intermediate sheath fills the notches between the cables the surfaces of the single wires of the wire pair almost completely from (claim 2) and focuses closely on the single wire insulation, so that a kind of "embedding" of the symmetrically stranded Single cores in the intermediate sheath material trains. The intermediate sheath is so tight the conductor insulation of the single cores, for example when laying the cable in any situation in the specified stranding position remain.

The data cable preferably consists of several double lines, which overall are surrounded by an overall shield are (claim 3). Such an additional overall shield additionally improves the transmission properties, in particular by sources of interference outside the data cable only much less due to the shielding Can induce interference signals in the data cable.

The overall shielding particularly advantageously touches the other shields in the double lines and is due these shields in electrical contact (claim 4). On the one hand, the overall shielding has the function the shielding of the double lines to the same potential, e.g. Earth potential to force. This allows you to Improve transmission properties additionally. On the other hand the overall shield holds several double lines together.

The data cable particularly preferably has an all-encompassing one Outer jacket on (claim 5). Even the outer jacket can perform the function of holding several double lines together. The outer jacket also protects against penetration of moisture and additionally improves the mechanical stability and resilience of the data cable.

In a further embodiment, there is between each pair of wires and the associated intermediate sheath a film, in particular a polyester film, arranged (claim 6). This film is used to separate the intermediate sheath and individual wires. As already mentioned above, you can use the intermediate coat extrude onto the wire pair. Actually, it would to a very strong connection between wire pair and Guide intermediate sheath so that when exposing the veins, such as it is necessary for connections, for example, for removal of the intermediate jacket come to considerable problems would.

To facilitate the process of removing the sheath, one can therefore advantageously see a corresponding one Release film. This separating film then fulfills a similar one Function like the growth of single wires, namely lightening the separation of veins and intermediate sheath. Especially preferably a wax bath of the veins is carried out as well as a separating film between the wires and the intermediate sheath inserted. This release film is very thin. Typically their thickness is in the range of approx. 0.1 mm.

The data cable preferably has one in comparison to one corresponding data cables of the same impedance, for example 100 ohms, but without intermediate sheath, thinner wire insulation on (claim 7). A comparable data cable without an intermediate sheath contains, as already described at the beginning, also a pair of wires and one surrounding the pair of wires Shielding. Comparable data cable in this sense means equal impedance, the impedance of a double line is meant with symmetrical wiring and grounded shield. With known cables (with shielding, but without intermediate mat) the thickness of the wire insulation serves to set a certain desired impedance value, on the one hand because they are the distance of the Conductors to each other and the distance between the conductors intended for shielding. For example, to have an impedance of Achieving 100 ohms is generally a relatively thick core insulation required. In the invention is the Shielding due to the intermediate sheath in a larger one Distance to the conductors of the wire pair as it passes through the Wire insulation alone would be specified. This makes possible, to make the wire insulation thinner. Through these measures is the distance between the conductors of the pair of wires reduced, on the other hand, their distance from the shield enlarged. While with conventional cables (as at the beginning mentioned) the (total) diameter of the conductor and core insulation Is 1.6 mm - around a cable with an impedance of 100 ohms to produce - one comes with an inventive Data cable with a corresponding diameter of 0.9 - 1.4 mm, in particular approximately 1.35 mm. It is very advantageous because of conventional insulation displacement connections allow only wire thicknesses of 1.4 mm. Due to the these conventional insulation displacement connections can now be used for wire thicknesses can be easily contacted. A lesser one The conductor diameter of known cables was not possible, otherwise an impedance of 100 ohms would not have can be achieved.

Because of these advantages, the wire insulation can be compared a comparable (known) cable with the same impedance be made 15% to 40% thinner (claim 8). In addition to the better compatibility with conventional connector systems Thinner wire insulation also saves material and allows higher production speeds. Because of the thinner core insulation - there is the core i.a. lie directly on top of each other - also the distance between the conductors less, e.g. it is with a reduced wire thickness of 1.35 mm also only 1.35 mm (since the conductors in the Center of the insulation). The intermediate coat is then designed so that it is a at the thinnest point Thickness from 0.2 to 0.3 mm and one at its thickest point Has a thickness of about 1 mm. The arrangement "pair of wires with Intermediate sheath and shield "(double line) a total diameter of about 3.2 mm. Because of the above Advantages are in a special configuration Invention of the diameter of the wire insulation including Conductors at most 1.4 mm (claim 9), e.g. with an impedance of 100 ohms and a conductor diameter of 0.5 - 0.8 mm, in particular approximately 0.64 mm.

This results in a data cable with four double lines therefore a total cable diameter of 9 mm. With conventional This diameter is for cables without an intermediate sheath larger than 10 mm. This reduction in diameter is based on the relatively high dielectric constant of the (not or only little foamed) intermediate sheath material (it is about 2.2 for polyethylene) compared to that the strongly foamed wire insulation in the state of the art. It is beneficial for several reasons. On the one hand material can be saved, but also used a cable of a certain length takes up less space. This has an advantageous effect when laying the cables in narrow cable spaces and the size of cable drums out.

As already indicated above, in special configurations the impedance of the data cable 100 Ohm (claim 10) and that with symmetrical wiring of the pair of wires. Symmetrical wiring means that not the impedance between the two wires on the one hand and shielding is measured on the other hand, but between the wires of a pair of wires. The shield is usually at a different potential than that Single wires, for example to earth potential.

A special embodiment provides that the data cable has at least two twisted double lines, which in the essentially identical twist lengths (hereinafter double-line twist lengths called) and opposite twist directions have (claim 11).

By the opposite directions of swirl and the essentially identical twist lengths of both double lines you get a data cable with excellent decoupling, especially magnetic decoupling, both Wire pairs. This makes the crosstalk properties, in particular the near-end crosstalk properties, particularly good.

In conventional Dieselhorst Martin fours, the different Having swirl lengths results from the different twist lengths an instability of the impedance at higher frequencies. With this particular twist the impedance curve becomes more even as the swirl lengths of two double lines (forming a four) one Fours are the same. The invention therefore achieves one more stable impedance curve.

Furthermore, the group delays are due to different twist lengths adversely affected by conventional cables. The reason for this is the different length of the Wire pairs, e.g. with known DM four. This negative Behavior is improved by the invention or completely eliminated, since the lengths of both (forming a foursome) Wire pairs are the same size.

• verbesserte Entkopplung der aus Aderpaaren gebildeten Doppelleitungen,
• geringeres Nebensprechen, insbesondere Nahnebensprechen,
• stabilerer Impedanzverlauf,
• verbessertes Gruppenlaufzeiten-Verhalten und
• sehr geringe Abweichung der Betriebskapazitäten voneinander.

Due to the special twist, the following main advantages are achieved:

• improved decoupling of the double lines formed from wire pairs,
• less crosstalk, especially near crosstalk,
• more stable impedance curve,
• improved group runtime behavior and
• very little deviation of the operating capacities.

Two such double lines (arranged in a foursome) are particularly suitable for data transmission with high frequencies and for frequencies from 1 MHz up to Frequencies of typically 600 MHz, but also up to to frequencies from 1 to 5 GHz. This is particularly suitable such data cables for data cables according to category 5 and 6, i.e. Data cables up to 300 MHz or 600 MHz, according to the Euronorm EN 50173 and according to the draft standard DIN 44312-X. Preferably is the double line twist length used in the Range from 15 to 70 mm.

Due to the special twist, you also get without an intermediate jacket Data cable with very good transmission properties, so that independent protection is also claimed for this becomes.

The data cable preferably contains at least one core bundle with four double lines, each with two double lines same and each other two double lines different Have double line swirl lengths (claim 12). In a corresponding preferred method four double lines connected to form a core bundle, where the double line twist lengths of each two double lines are the same and two of each other Double lines can be selected differently (claim 22).

This consists of four double lines or eight single wires existing core bundle has only two different ones Double line twist lengths. The decoupling of two double lines with different double line twist lengths takes place through an optimized gradient ratio, i.e. the different double line twist lengths are in an optimized relationship to each other. The decoupling two double lines with the same double line twist lengths takes place by the opposite twist direction of the double lines (with the same double line twist length).

Such a data cable either has only one wire bundle with four double lines or several such wire bundles on. These core bundles can either be the same or different Twists, especially different ones Have double line swirl lengths. It applies to everyone Core bundle the above Condition, namely that there are only two has different double line twist lengths.

Preferably, either have two immediately adjacent or two opposite double lines essentially same double line twist length and opposite Swirl direction on (claim 13). Consider a cross section through the (formed of four double lines) Core bundle, the cross-sectional centers are in this embodiment of the four double lines on the corners a square, in particular a square, a rectangle or a diamond. For the arrangement of the four double lines then there are two possibilities, namely on the one hand that two double lines with the same double line twist lengths and opposite twist direction opposite corners, on the other hand, that these double lines lie on immediately adjacent corners of the square.

If you run through the corners of the square, for example in Clockwise there are two other options for that Twist directions of the double lines. These twist directions can either alternate so that - the square continuous - the following swirl directions result: right-left-right-left; or the twist directions of twice two adjacent double lines can be the same, so that the following twist directions result: right-right-left-left.

In the arrangement, in which two opposite double lines same double line twist lengths and opposite Having a twist direction, the following results Advantage: The geometry of all four double lines (to each other) is retained even in the case of swirl, since then the The four double lines can only be twisted together is. Different twist lengths of two with each other twisted double lines are not in this arrangement possible.

In the arrangement in which two immediately adjacent Wire pairs of the same double line twist length and opposite Have twist direction, these form two double lines - at least functionally, i.e. not necessarily figurative - a foursome. Then there are different ones Twists of two double lines to one ("functional") foursome possible, especially different ones Four swirl lengths and swirl directions. The distances the wire pairs of two ("more functional") fours change then along the length of the cable. - A common twist the two ("functional") foursome into a core bundle is also possible.

The cross-sectional centers of the double lines are preferably located of a core bundle essentially side by side on a, in particular straight or curved, line (Claim 14). The cross-sectional center is the center to understand a cross section through a double line. In this embodiment, a line connects the Cross-sectional centers of four double lines one Core bundle (mentally) with each other. If the line is straight there is a special type of ribbon cable, at the twisted double lines in parallel "in a row" lie side by side. Basically there are also several, for example three to ten, such lines on top of each other possible lying down. The result is a multi-layer ribbon cable.

The line can also be curved. For example, this is then the case when the core bundle is part of a layer stranding is, i.e. several core bundles in concentric Layers are arranged. Even then, the wire pairs are parallel "in a row" side by side. Every single layer can consist of several core bundles. The entire data cable can in turn consist of several or many, for example three to ten, such layers be built.

1. Die erste und zweite Doppelleitung einerseits und die dritte und vierte Doppelleitung andererseits weisen jeweils im wesentlichen gleiche Doppelleitungs-Drallänge und entgegengesetzte Drallrichtung auf. Dann können die Drallrichtungen von zweiter und dritter Doppelleitung bzw. von erster und vierter Doppelleitung entweder gleichsinnig oder gegensinnig ausgebildet sein. Dabei ergeben sich folgende Alternativen der Reihenfolge der Drallrichtungen:

a) rechts-links-links-rechts;

b) rechts-links-rechts-links;

c) links-rechts-rechts-links;

d) links-rechts-links-rechts.

2. Die erste und dritte Doppelleitung einerseits und die zweite und vierte Doppelleitung andererseits weisen jeweils im wesentlichen gleiche Doppelleitungs-Drallänge und entgegengesetzte Drallrichtung auf. Dann können die Drallrichtungen von erster und zweiter Doppelleitung bzw. von dritter und vierter Doppelleitung entweder gleichsinnig oder gegensinnig ausgebildet sein. Dabei ergeben sich folgende Alternativen der Reihenfolge der Drallrichtungen:

a) rechts-links-links-rechts;

b) rechts-rechts-links-links;

c) links-rechts-rechts-links;

d) links-links-rechts-rechts.

3. Die erste und vierte Doppelleitung einerseits und die zweite und dritte Doppelleitung andererseits weisen jeweils im wesentlichen gleiche Doppelleitungs-Drallänge und entgegengesetzte Drallrichtung auf. Dann können die Drallrichtungen von erster und zweiter Doppelleitung bzw. von dritter und vierter Doppelleitung entweder gleichsinnig oder gegensinnig ausgebildet sein. Dabei ergeben sich folgende Alternativen der Reihenfolge der Drallrichtungen:

a) rechts-rechts-links-links;

b) rechts-links-rechts-links;

c) links-links-rechts-rechts;

d) links-rechts-links-rechts.

In an embodiment with "double-line cross-sectional center points lying on a line", two adjacent and / or two non-adjacent double lines preferably have essentially the same double-line twist length and opposite twist direction (claim 5). The following three variants of the four "in a row" double lines can then result:

1. The first and second double lines on the one hand and the third and fourth double lines on the other each have essentially the same double line twist length and opposite twist direction. Then the swirl directions of the second and third double lines or of the first and fourth double lines can be designed either in the same direction or in opposite directions. The following alternatives result in the order of the swirl directions:

a) right-left-left-right;

b) right-left-right-left;

c) left-right-right-left;

d) left-right-left-right.

2. The first and third double lines on the one hand and the second and fourth double lines on the other hand each have essentially the same double line twist length and opposite twist direction. Then the swirl directions of the first and second double lines or of the third and fourth double lines can be designed either in the same direction or in opposite directions. The following alternatives result in the order of the swirl directions:

a) right-left-left-right;

b) right-right-left-left;

c) left-right-right-left;

d) left-left-right-right.

3. The first and fourth double lines on the one hand and the second and third double lines on the other hand each have essentially the same double line twist length and opposite twist direction. Then the swirl directions of the first and second double lines or of the third and fourth double lines can be designed either in the same direction or in opposite directions. The following alternatives result in the order of the swirl directions:

a) right-right-left-left;

b) right-left-right-left;

c) left-left-right-right;

d) left-right-left-right.

The different double line twist lengths are particularly preferred optimized for maximum decoupling (Claim 16). The decoupling is strongly influenced by the Relationships of the double line twist lengths are affected. It on the one hand, there are conditions that require a high level of decoupling of Ensure double lines, on the other hand there are unfavorable Ratios leading to a larger coupling and thus lead to stronger crosstalk. In this embodiment the conditions of the data cable chosen to ensure maximum decoupling.

The individual are preferably twisted (in each case) Double lines, shared by two double lines and / or the core bundle or the core bundle with, without or with partial reverse rotation (claim 17). With such a Twisting leads to further decoupling the double lines of the data cable and also a minimization of interference from outside the data cable the data cable.

The effect of the reverse rotation is exemplified by the stranding explained two double lines to a four: With a twist without turning back, the two Double lines twisted to the foursome so that the axes of the coils on which the (especially twisted) Double lines are wound up with a stranding basket are firmly connected. When twisting the stranding basket each double line receives an additional twist. The resulting double line twist lengths are thus reduced or enlarged, depending on whether the twist directions of double line and four of the same or opposite are. However, this type of twist affects not the mutual position of the wires of both double lines. That is why the effective double line twist length equal to the manufacturing twist of each double line.

When swirling with reverse rotation, the position of the Coil axes in space unchanged. This also applies to the Location of the double lines. The double lines experience at this type of twist no additional torsion. However becomes the effective double line twist length due to the reverse rotation changed. The effective twist length of a double line is enlarged or reduced, depending on whether the Twist directions of double line and four of the same or are opposite.

Between these two extreme cases, namely swirl with and without backward rotation, the swirl can be foursome but also with only partial reverse rotation. To if you twist the position of the coil axes during the twisting, which, for example, are rotatably arranged on the stranding basket are, the twist of the coil axes different is chosen for the twist of four.

The production takes place in a preferred core bundle of the four double lines without twisting while twisting of the double lines to the core bundle with reverse rotation he follows.

The shield or each individual shield is preferred foil-like, braid-like and / or other conductive Formed materials (claim 18). Braided shielding is particularly suitable to shield against low frequency signals while a foil-like shield, in particular for achieving a particularly effective shield against high frequencies is suitable. If you combine a film-like and a braid-like Shielding from each other results in an ideal Shielding for (essentially) the entire, technical relevant frequency range. During film-like or braid-like shields preferably made of metallic Material, e.g. Copper, tinned copper or aluminum exist, but can also be shields from others conductive materials are used. For that come in particular conductive plastics, for example polyolefins, into consideration. Such plastics are inexpensive and Easy to process. They are preferably considered thin Layer on cores, double cables, quads and / or core bundles or the data cable applied and if necessary by one encased surrounding coat.

At least one shield advantageously consists of one conductive coating, especially a conductive powder coating, a conductive varnish, a conductive, for example metallized, plastic and / or one extrudable conductive material (claim 19). Especially is the coating directly on the surface of the Intermediate jacket applied so that the intermediate jacket and the shield surrounding it is in one piece. Advantageous one achieves a very high level with such coatings uniform impedance over the length of the cable. Furthermore is the process of applying such coatings a simple, quick operation and therefore cheaper than applying a film.

With regard to further advantageous refinements of the method (Claim 23) is based on the above statements referred to the configurations of the data cable, which also for the procedure is valid.

Fig. 1

eine schematische beispielhafte Darstellung einer Doppelleitung im Querschnitt mit Abmessungsangaben;

Fig. 2

eine schematische beispielhafte Darstellung eines Zwischenmantels im Querschnitt;

Fig. 3

eine schematische beispielhafte Darstellung eines Datenkabels mit vier Doppelleitungen im Querschnitt;

Fig. 4

eine schematische beispielhafte Darstellung eines weiteren Datenkabels mit vier Doppelleitungen im Querschnitt;

Fig. 5

eine schematische beispielhafte Darstellung eines weiteren Datenkabels mit vier Doppelleitungen im Querschnitt;

Fig. 6

eine erste schematische beispielhafte Verdrallung von vier Doppelleitungen zu einem Aderbündel;

Fig. 7

eine zweite schematische beispielhafte Verdrallung von vier Doppelleitungen zu einem Aderbündel;

Fig. 8

eine dritte schematische beispielhafte Verdrallung von vier Doppelleitungen zu einem Aderbündel;

Fig. 9

eine schematische beispielhafte Darstellung eines weiteren Datenkabels mit einem Aderbündel im Querschnitt.

The invention will now be explained in more detail on the basis of exemplary embodiments and the attached schematic drawing. The drawing shows:

Fig. 1

a schematic exemplary representation of a double line in cross section with dimensions;

Fig. 2

a schematic exemplary representation of an intermediate jacket in cross section;

Fig. 3

a schematic exemplary representation of a data cable with four double lines in cross section;

Fig. 4

a schematic exemplary representation of a further data cable with four double lines in cross section;

Fig. 5

a schematic exemplary representation of a further data cable with four double lines in cross section;

Fig. 6

a first schematic exemplary twist of four double lines to form a core bundle;

Fig. 7

a second schematic exemplary twist of four double lines to form a core bundle;

Fig. 8

a third schematic exemplary twist of four double lines to form a core bundle;

Fig. 9

a schematic exemplary representation of a further data cable with a core bundle in cross section.

In the figures, they have essentially the same function Parts have the same reference numerals. It will also be throughout present description numerals "x" in the sense of at least "x" and only preferably in the sense of exactly "x" Understood.

Fig. 1 illustrates the basic structure of a data cable 1 and only consisting of a double line. The double line has two single wires A, B. The single wire A consists of a conductor A 'and a Conductor A 'enveloping core insulation A' '. Corresponding applies to core B, which also has a conductor B 'and a wire insulation B '' surrounding this conductor B '' having. The wires A, B are twisted together (in 1) and form a pair of wires. This The pair of wires is surrounded by an intermediate jacket C made of insulating Plastic, especially polyethylene, which again from a shield D, e.g. a conductive Coating (such as a powder coating) is surrounded.

As shown in Fig. 2, the intermediate jacket C is in cross section looks round at the outside. This outer contour of the The intermediate sheath in the cross section is either circular, like shown in Fig. 2, or oval in other embodiments. The inner contour of the intermediate jacket is - in cross section considered - 8-shaped. The intermediate coat is hollow within this 8-shaped contour. This cavity serves to accept the wires A, B.

Due to the round outer contour of the intermediate sheath the surrounding shield D very evenly on the Intermediate sheath. The shield D therefore also changes mechanical load of the arrangement its position to the intermediate jacket C almost not. The intermediate jacket also prevents C also a shift of the single wires A, B. How Already explained at the beginning, this fixation is one-sided the single wires A, B to each other, on the other hand the Single wires A, B for shielding D important for the electrical Properties of the double line serving as waveguide.

Fig. 1 also shows the dimensions of an embodiment a double line. The diameter of the Single cores A, B are 1.35 mm each. Hence is the distance between the centers of the conductors A ', B' also 1.35 mm because the single wires A, B are in contact with each other stand. The intermediate sheath C has at its thinnest point a thickness of 0.2 to 0.3 mm, which is the case in Fig. 1 shown position to the left of the wire A or right from the core B. At its thickest point, the intermediate sheath a thickness of 1 mm. The shield D has a negligible thickness. This gives a diameter the double line of about 3.2 mm.

With these dimensions, a data cable 1 is obtained an impedance of 100 ohms. By using the intermediate sheath C you can get the average attenuation of the Data cable 1 at a frequency of 100 MHz of 17 dB a comparable cable without intermediate sheath C to 15 dB to reduce. Furthermore, it is possible through the intermediate jacket C defined electrical properties of the data cable 1 up to a range of greater than 1000 MHz create. With a corresponding cable construction without Intermediate jacket is not possible up to such high Define frequencies up good electrical properties.

Fig. 3 shows a data cable 1 consisting of four double lines. Each of the four double lines is according to the Double line constructed from Fig. 1. These four double lines are surrounded by an overall screen E. An outer jacket F encloses the overall screen E. The overall screen E surrounds the shields D of the four double lines in this way closely that good electrical contact between all Shielding D, E is guaranteed. By this measure are all shields D, E on the same electrical Potential. Finally, the tight-fitting prevents Overall shielding E also shifting the layers of the double lines and thus also contributes to defined Conditions at. The outer jacket F finally serves for mechanical protection of the cable, but also against penetration of moisture.

A data cable according to the arrangement according to FIG. 3 has one Outside diameter of 9 mm. A comparable conventional one Cables with the same impedance, but without intermediate sheaths, would have a diameter of approx. 10 mm.

4 is used for further schematic illustration a data cable 1, in particular the special twist the double lines, also in the form of a Cross section through the data cable 1. The data cable 1 points as an outer shell an insulating outer jacket 2. This insulating outer jacket 2 encloses an outer Total shielding 3. Four double lines 4, 5, 6, 7 are located within the outer overall shield 3 or inside the insulating jacket 2.

4 are four Double lines 4-7 in a flexible material 8, for example a plastic, embedded. This flexible Material 8 is nevertheless so dimensionally stable that it provides stabilization the relative position of the double lines 4-7 to each other guaranteed. In particular, it prevents accidental Twisting the double lines 4-7 for example when laying the data cable 1. The flexible material 8 thus forms a further intermediate jacket embedding. This further intermediate jacket embedding essentially fills all gaps between the double lines and therefore stabilizes their relative position to each other. Furthermore, the intermediate jacket embedding helps to maintain it the twist lengths of the double lines as they change the twist, i.e. an additional torsion of the Can prevent double lines.

In other embodiments (see above) is the flexible material 8 not available. Then the position stabilization the double lines 4-7 achieved in that the outer jacket 2 or the overall shield so tight around the double lines 4-7 is created that essentially none Shifting the position of the double lines is possible.

Each double line 4-7 has a shield 9, 10, 11, 12 and an intermediate jacket 13, 14, 15, 16. The shield 9-12 surrounds the intermediate jacket 13-16. Any double line 4-7 has two wires 17, 18, 19, 20, 21, 22, 23, 24 on.

In order to achieve a special decoupling of the double lines, the cable is constructed as follows: two each Conductors 17, 18 and 21, 22 each become a double line 4 or 6 twisted. Both double lines 4 and 6 have the same swirl length but opposite swirl direction. in the individual, the wires 17, 18 of the double line 4 are twisted to the right and the wires 21, 22 of the double line 6 are twisted to the left. These two double lines 4 and 6 form one first functional unit in the sense that two double lines same swirl length and different swirl direction exhibit.

A second functional unit is created by the double lines 5 and 7. Two twisted cores form 19 and 20 the double line 5 and two left-hand twisted Veins 23 and 24 the double line 7. Both double lines 5 and 7 have the same swirl length and opposite Swirl direction. The twist length of the double lines 5 and 7 is different from that of the double lines 4 and 6. Die Twist lengths are coordinated and in terms of optimized maximum decoupling. They are in the range of 15 to 70 mm or larger.

The four double lines 4-7 are each in the corners of a square or square. The double lines 4-7 each functional unit is in opposite Corners of the square or - in other words - two (diagonal) opposite double lines form a functional one Unit.

The core bundle consisting of four double lines 4-7 becomes also twisted, preferably with a core bundle twist length from 35 to 200 mm. The twist of the Single wires 17-24 to double lines 4-7 are made without reverse rotation. The twisting of the double lines 4-7 into one Figure eight configuration (core bundle) takes place with reverse rotation. The latter twist is basically similar to one Star-four stranding, but instead of single cores Double lines 4-7 are twisted together.

5 shows a second exemplary embodiment of a data cable 1. Fig. 5 corresponds essentially to Fig. 4, however form two on adjacent to each other Corners of the (mentally formed) quadrilateral double lines 4 and 5 or 6 and 7 each a functional unit. In detail, the wires 17, 18 of the double line 4 twisted to the left and the other two wires 19, 20 of the - belonging to the same foursome - double line 5 twisted to the right. Correspondingly, the wires 21 and 22 of the double line 6 left-hand twisted and the wires 23 and 24 of the double line 7 twisted to the right.

According to FIG. 5 there are further possibilities for swirling the double lines 4-7. It is a common one Twisting of the double lines 4-7 possible - similar to with a star-four stranding (as already shown in FIG. 4 explained). Alternatively, however, is one of the other independent twist of two double lines 4, 5 or 6, 7 possible, similar to a Dieselhorst-Martin stranding, but with the difference that instead of single wires (with Dieselhorst-Martin stranding) two double lines each 4, 5 and 6, 7 are swirled.

6 illustrates the twist according to the star-four principle, with two opposite double lines 4, 6 and 5, 7 each form a functional unit. There is only a common twist of all four double lines 4-7 possible. However, the star-four principle can also be used Use in an arrangement according to FIG. 5 find, i.e. if two immediately adjacent double lines 4, 5 and 6, 7 each form a functional unit. The twisting according to the star-four principle has that Advantage that the distances between the double lines 4-7 remain constant along the length of the cable.

Fig. 7 shows a possible twist for a data cable 5, i.e. if two immediately adjacent Double lines form a functional unit. 4, the double lines 4 and 5 are one functional unit twisted clockwise, as well the double lines 6 and 7. All four double lines 4-7 are also twisted clockwise together. Also is a left-hand twist of the double lines 4-7 possible.

8 also form two immediately adjacent Double lines 4 and 5 or 6 and 7 each a functional Unit. Here the double lines 4 and 5 are clockwise twisted into a functional unit, while the Double lines 6 and 7 counterclockwise to another functional unit are twisted. The entire configuration consisting of the four double lines 4-7 again twisted clockwise, but can also turn counterclockwise be twisted.

Both in the configuration according to FIG. 7 and in the 8 change the distances of the Single wires of different double lines along each other the longitudinal direction of the cable.

9 illustrates the basic structure of a data cable 1 according to a further exemplary embodiment. The Data cable 1 is again shown in cross section. The Cross-sectional centers 25, 26, 27, 28 of the double lines 4-7 lie on a line 29. In the illustrated embodiment line 29 is straight. With others (not illustrated embodiments, the line 29 is curved. For the formation of a functional unit the variants explained above, namely that two neighboring ones and / or two non-adjacent double lines each form a functional unit. Can accordingly the twist directions vary (see above).

Basically, all figures also serve to explain the Building a foursome. You get through on all figures Omitting two double lines such a foursome, e.g. 4 by omitting the double lines 5 and 7. In this example, the Shape of the jacket 2, the flexible material 8 and possibly the change outer shield 3 in such a way that - instead a circular - an oval sheathing the double lines surrounds. In addition, the two double lines are so close to each other that in extreme cases touch. For example, by omitting the Double lines 4 and 7 in Fig. 9 already two very tight mutually lying double lines 5 and 6, by a oval wrapping are surrounded.

The various configurations shown in FIGS. 4-9 offer different ways to optimize a data cable with very good transmission properties, in particular very good decoupling of each forming a data line Double lines and therefore very little crosstalk.

Claims (23)

Data cable (1) with at least one double line, comprising: a) a pair of wires (4-7) consisting of two twisted single wires (A, B, 17-24), each with a conductor (A ', B') and a wire insulation surrounding the conductor (A ', B') (A '', B '', 13-16), b) an intermediate sheath (C) surrounding the pair of wires (4-7) and c) a shield (D) surrounding the intermediate sheath (C), d) wherein the intermediate sheath (C) at least partially fills notches between the surfaces of the individual wires (A, B, 17-24) of the wire pair (4-7), so that it fixes the geometry of the double line. Data cable (1) according to claim 1, wherein the intermediate sheath (C) the notches between the surfaces of the Single wires (A, B, 17-24) of the wire pair (4-7) almost completely filled out. Data cable (1) according to one of the preceding claims with several double lines, which in total from are surrounded by an overall shield. A data cable (1) according to claim 3, wherein the overall shield the other shields of the double lines touched and in electrical contact with them Shields stands. Data cable (1) according to one of the preceding claims, which has an all-round outer jacket. Data cable (1) according to one of the preceding claims, in which between wire pair (4-7) and intermediate sheath (C) a film, in particular polyester film, is arranged is. Data cable (1) according to one of the preceding claims, which is compared to a corresponding data cable same impedance, for example 100 ohms, but without intermediate sheath (C), thinner wire insulation (A ", B", 13-16). A data cable (1) according to claim 7, wherein the wire insulation (A '', B '', 13-16) is at least 15% thinner. Data cable (1) according to claim 7 or 8, wherein the Wire insulation diameter (A '', B '', 13-16) including conductors (A ', B') is at most 1.4 mm. Data cable (1) according to one of the preceding claims, which with symmetrical wiring of the wire pair (4-7) has essentially 100 ohm impedance. Data cable (1) with at least two twisted double lines, in particular according to one of the preceding claims, the a) essentially the same twist lengths (double-line twist lengths) and b) opposite twist directions exhibit. Data cable (1) according to claim 11, which is a core bundle with four double lines, each with two double lines the same and each other two Double lines different double line twist lengths exhibit. The data cable (1) of claim 12, wherein either two immediately adjacent or two opposite Double lines have essentially the same double line twist length and opposite twist direction exhibit. Data cable (1) according to one of claims 12 or 13, where the cross-sectional centers of the double lines of a core bundle essentially side by side on a, especially straight or curved, Line. A data cable (1) according to claim 14, in which two Adjacent and / or two non-adjacent double lines in each case essentially the same double line twist length and have opposite twist direction. Data cable (1) according to one of claims 12 to 15, which the different double line twist lengths optimized for maximum decoupling. Data cable (1) according to one of the preceding claims, with (each) a twist of the individual double lines, of two double lines together and / or the core bundle (s) with, without or with partial Reverse rotation. Data cable (1) according to one of the preceding claims, the shield (s) being foil-like, braid-like and / or having other conductive materials is / are. Data cable (1) according to one of the preceding claims, wherein the shield (s), in particular the shield (s) surrounding the intermediate sheath (C) (D) (D) made of a conductive coating, in particular a conductive powder coating, a conductive varnish, a conductive, for example metallized, plastic and / or an extrudable conductive material exists / exist. Method for producing a data cable (1) with at least one double line, the production of the double line comprising the following steps: a) Twisting of two individual cores (A, B, 17-24), each of which a conductor (A ', B') and a wire insulation (A '', B '', 13 surrounding the conductor (A ', B') -16) to a pair of wires (4-7); b) Surrounding the wire pair (4-7) with an intermediate jacket (C), the notches between the surfaces of the individual wires (A, B, 17-24) of the wire pair (4-7) at least partially fills, so that it the geometry of the Double line fixed and c) Surrounding the intermediate sheath (C) with a shield. Method for producing a data cable (1), in particular according to claim 20, with the (further) steps: a) swirling a first double line with a first double line twist length; b) twisting a second double line with a second double line twist length; c) Choosing the first double line swirl length substantially equal to the second double line swirl length and d) Choosing the twist direction of the first double line against the twist direction of the second double line. 22. The method of claim 21, wherein four double lines are connected to each other to form a core bundle, where the double line twist lengths of two Double lines are the same and each other two Double lines can be selected differently. Method according to one of claims 20 to 22 for manufacturing of a data cable (1) according to one of the claims 1 to 19.

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