EP3882931A1 - Cable - Google Patents

Abstract

Cable, in particular data cable for the transmission of data in telecommunications, communications or computer technology, comprising at least one conductor bundle (1) and a shield (2) for shielding the conductor bundle (1) and / or the wires (3, 4) of the conductor bundle (1), characterized in that the ratio of a lay length (L1) of the conductor bundle (1) to a lay length (L2) of the shielding (2) is between 0.7 and 1.3.

Description

FIELD OF THE INVENTION

The invention relates to a cable, in particular a data cable for the transmission of data in telecommunications, message transmission or computer technology, in particular for the automotive industry, comprising at least one conductor bundle and a shield for shielding the conductor bundle and / or the wires of the conductor bundle.

STATE OF THE ART

In cables for data transmission, in particular with high data transmission rates, such as those used in vehicles in particular, there are regularly high attenuation peaks in insertion loss and return loss, especially in the relevant frequency ranges. This phenomenon is attributed to symmetry effects that result from periodicities in the internal structure of such cables.

The cables in question are usually made up of a large number of cores, each of which consists of a conductor (solid conductor wire or stranded wire) and insulation surrounding the conductor. These wires are combined in pairs to form wire pairs, which are each surrounded by a pair shield or pair shield. Depending on whether the wires of the individual wire pairs run parallel to one another or are twisted together, one speaks of "shielded parallel pair" or of "shielded twisted pair" cables.

In addition, the individual wire pairs can also be twisted with one another in order to form a stranding element. In order to be able to clearly differentiate the twisting of the cores of a core pair and the twisting of the core pairs of a stranding element, one speaks (instead of twisting) of stranding of the individual core pairs.

A conductor bundle of the cable can now be formed by one or more stranding elements, or also by one or more wire pairs that are not stranded with one another. In many cases, however, the conductor bundle is still surrounded by an overall shield and a cable sheath.

While the twisting of the wires is intended to ensure better protection against electrical and magnetic interference fields as well as an extensive elimination of the influence of external fields, the stranding of the wire pairs leads in particular to the desired flexibility or stability of the respective cable. The pair shielding should also minimize crosstalk between adjacent wire pairs and the overall shielding should ensure protection with regard to electromagnetic compatibility and electromagnetic interference.

In particular, the arrangement of the pair shielding on the individual wire pairs is of great importance with regard to the attenuation peaks described above. For example, suggests EP 3 172 741 B1 propose to arrange a dielectric intermediate film between the pair of wires and the pair shield, the lay length of which is not constant over the entire length of a pair of wires, but preferably varies periodically over the length of the pair of wires. This is intended to reduce negative symmetry effects, which are ascribed to the pair shielding wound around the wire pair with a constant lay length, and to improve the transmission properties of the respective cable even at high transmission rates or frequencies.

In practice, however, this solution turns out to be disadvantageous, since the application of additional adhesive foils between the pair of wires and pair shielding is associated with a high level of effort and expense in terms of processing. The same applies to similar solutions based on the concept of disrupting the symmetry of the cable structure, for example by stranding individual wire pairs with different lay lengths.

OBJECT OF THE INVENTION

It is therefore an object of the invention to overcome the disadvantages of the prior art and to propose a cable which has significantly improved transmission properties in a respective frequency range compared to the prior art.

In particular, attenuation peaks in the insertion loss and / or the return loss should be avoided or displaced from the relevant frequency range.

The construction of the proposed cable should be kept significantly simpler than in the prior art, so that inexpensive production is possible.

In particular, the cables according to the invention should be suitable for use in vehicles or in the automobile industry.

DISCLOSURE OF THE INVENTION

One object is achieved by a cable according to the invention, in particular a data cable for the transmission of data in telecommunications, communications or computer technology, comprising at least one conductor bundle and a shield for shielding the conductor bundle and / or the wires of the conductor bundle, by the ratio of a lay length of the conductor bundle to a lay length of the shielding between 0.7 and 1.3.

The term "lay length" is usually understood, and also within the scope of the present invention, to mean the length of that section running in the longitudinal direction of the cable which requires a wire, a pair of wires or a shield for a complete 360 ° rotation.

In particular, the lay length of a twisted pair of wires denotes the length that one wire of the wire pair needs for one complete turn in the wire pair, the lay length of a stranding is the length that a wire pair needs for a complete turn in the stranding, and the lay length of a shield is the length which requires a corresponding banding that forms the respective shielding for a complete rotation. The term lay length is therefore synonymous in each context with a period of twisting a pair of wires, stranding individual pairs of wires with one another, or wrapping a band around a pair of wires (pair shielding) or around the entire conductor bundle (overall shielding).

According to the invention it is now provided that a lay length of the conductor bundle is not less than half and not more than 1.5 times the lay length of the shielding. This matching of the lay lengths to one another allows the transmission properties of the cable according to the invention to be optimized. Use is made of the knowledge that both the periodic twisting or stranding of the conductor bundle and the periodic winding of the (pair or overall) shielding produce peaks in the insertion loss curve. Due to the inventive coordination of the lay lengths, attenuation peaks in the insertion loss, which attenuation peaks are due to the regular arrangement of the shielding, coincide with those attenuation peaks which are due to the respective lay length of the twisting and / or stranding of the wire pairs. If the lay length of the twisting and / or stranding of the wire pairs is selected so that the corresponding main peak lies outside the relevant frequency range (by reducing the lay length, the main peak in the insertion loss shifts to higher frequencies), there is a noisy frequency range in the relevant frequency range. and peak-free transfer curve.

The ratio of the lay length of the conductor bundle to the lay length of the shield is preferably between 0.8 and 1.2; particularly preferably the ratio is essentially 1, so that the lay length of the conductor bundle corresponds to the lay length of the shielding or the two lay lengths are identical.

The lay length of the conductor bundle can relate to the period of twisting of the wires in a wire pair, or to the period of stranding individual wire pairs with one another in a stranding element.

The lay length of the shielding can refer either to the period of a pair of shielding, which pair of shielding surrounds a pair of wires for the purpose of shielding, or to the period of an overall shielding, which overall shielding surrounds the entire bundle of conductors. The pair shielding and / or the overall shielding is preferably formed by banding or a film made of a plastic, for example made of a thermoplastic such as PETP.

All of the lay lengths occurring in a cable according to the invention are particularly preferably identical. In particular, the lay length of all wire pairs stranded with one another can be identical and also be identical to the lay length of all pair shields and any overall shielding that may be present.

This enables a particularly smooth damping curve to be achieved.

The lay lengths with which the individual wire pairs are twisted with one another can be identical or different.

Cables according to the invention can be present, for example, as “shielded twisted pair” or as “shielded parallel pair” cables.

In a particularly preferred embodiment of the invention, the cable is a "shielded twisted pair" cable with a twisted pair of wires, in particular with a wire cross-section of 0.14 or 0.22 mm ² , and a pair of shielding surrounding the wire pair, the lay length of the wire pair and the lay length of the pair shield is in each case between 5 and 20 mm, but is preferably 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 mm.

The term wire cross-section denotes the cross-section of a conductor forming one wire of the wire pair, in particular a conductor cross-section.

In this embodiment, only a single twisted pair of wires can be present; By adapting the lay length of the wire pair according to the invention and that of the pair shielding surrounding the wire pair, a smooth, peak-free and noise-free transmission curve can be generated. A peak in the insertion loss of a corresponding cable only occurs at around 9 GHz.

In another preferred embodiment, a twisted pair of wires, in particular with a wire cross-section of 0.13 mm ² each, and an overall shielding surrounding the pair of wires are provided, the lay length of the wire pair and the lay length of the overall shield being between 5 and 15 mm, but preferably 9, 10 or 11 mm.

A particularly simple structure of the cable can thereby be ensured.

In the case of corresponding embodiments, the pair shielding can be omitted; alternatively, pair shielding can also be provided in addition to the overall shielding.

In a particularly preferred embodiment, a stranding element with two twisted wire pairs, each surrounded by a pair of shielding, and one is the Overall shielding surrounding the stranding element is provided, the lay length of the stranding of the two wire pairs, the lay length of the pair screening and the lay length of the overall screen each being between 5 and 15 mm, but preferably 9, 10 or 11 mm.

The lay length with which the wire pairs are twisted can also coincide with the lay lengths of the stranding, the pair shielding and the overall shielding. In addition, further stranding elements can also be provided in one embodiment of the cable according to the invention.

According to the invention, to achieve an object of the invention, a cable, in particular a data cable for the transmission of data in telecommunications, message transmission or computer technology, can also be provided, comprising at least one conductor bundle and a shield for shielding the conductor bundle and / or the wires of the conductor bundle, wherein the cable is designed as a "shielded parallel pair" cable and a wire pair with two parallel wires, in particular with a wire cross-section between 0.02 to 0.35 mm ² , particularly preferably 0.14 or 0.22 mm ^{2 each} , and a pair of shielding surrounding the wire pair is provided. If the lay length of the pair shield is between 3 and 7 mm, but preferably 5 mm, the transmission properties of a corresponding “shielded parallel pair” cable can be significantly improved. A width of a foil forming the pair shielding is particularly preferably not equal to the lay length of the pair shielding, that is to say the length that is required for wrapping the wire pair with the pair shielding.

In a further particularly preferred embodiment of the invention, it is provided that all wires of the conductor bundle have the same capacitance per unit length.

As a result, the attenuation properties of the cable according to the invention can be improved even further and additional peaks in the insertion loss can be avoided. A preferably one-sided lamination of the shielding, that is to say the pair shielding and / or the overall shielding, with an aluminum or copper layer is also advantageous.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail on the basis of exemplary embodiments. The drawings are exemplary and are intended to explain the concept of the invention, but in no way restrict it or reproduce it conclusively.

Fig. 1

eine schematische Schnittdarstellung eines erfindungsgemäßen Kabels mit einem Verseilelement mit zwei verdrillten Adernpaaren mit jeweils einer Paarschirmung und einer Gesamtschirmung

Fig. 2

eine schematische Schnittdarstellung eines erfindungsgemäßen Kabels mit einem verdrillten Adernpaar und Paarschirmung

Fig. 3

eine schematische Schnittdarstellung eines erfindungsgemäßen Kabels mit einem verdrillten Adernpaar, Innenmantel und Gesamtschirmung

Fig. 4

eine Dämpfungskurve (Einfügedämpfung) eines aus dem Stand der Technik bekannten Kabels

Fig. 5

eine Dämpfungskurve (Einfügedämpfung) eines erfindungsgemäßen Kabels

Fig. 6

ein erfindungsgemäßes Kabel in einer ersten Ausführungsform mit Paarschirmung

Fig. 7

ein erfindungsgemäßes Kabel in einer zweiten Ausführungsform mit Innenmantel

Fig. 8

ein erfindungsgemäßes Kabel in einer dritten Ausführungsform mit Paarschirmung und Gesamtschirmung

Fig. 9

ein erfindungsgemäßes "Shielded Twisted Pair"-Kabel

It shows:

Fig. 1

a schematic sectional view of a cable according to the invention with a stranding element with two twisted wire pairs, each with a pair of shielding and an overall shielding

Fig. 2

a schematic sectional view of a cable according to the invention with a twisted pair of wires and pair shielding

Fig. 3

a schematic sectional view of a cable according to the invention with a twisted pair of wires, inner sheath and overall shielding

Fig. 4

an attenuation curve (insertion loss) of a cable known from the prior art

Fig. 5

an attenuation curve (insertion loss) of a cable according to the invention

Fig. 6

a cable according to the invention in a first embodiment with pair shielding

Fig. 7

a cable according to the invention in a second embodiment with an inner jacket

Fig. 8

a cable according to the invention in a third embodiment with pair shielding and overall shielding

Fig. 9

a "shielded twisted pair" cable according to the invention

WAYS OF CARRYING OUT THE INVENTION

Fig. 1 shows a schematic sectional view of a cable according to the invention. The cable has two wire pairs 5, each of which includes a first insulated wire 3, a second insulated wire 4 and a pair of shielding 6 surrounding the two wires 3, 4. The wires 3, 4 of the wire pairs 5 are not routed in parallel in the cable, but are twisted in pairs to form a twist 8 (the circumference of the twisted wire pairs 5 is shown in FIG Fig. 1 indicated by the dashed lines provided with reference numeral 8; the direction in which the two wires 3, 4 are twisted with one another is indicated by the two arrows arranged within the twist 8).

The twisted wire pairs 5 are in turn twisted together in a similar manner in order to form a stranding 9 (the extent of the stranding is shown in FIG Fig. 1 indicated by the dashed line provided with reference numeral 9; the direction in which the wire pairs 5 are twisted with one another is indicated by the two arrows arranged outside the twist 8 but inside the stranding 9). For the semantic differentiation between the twisted wires 3, 4 and the wire pairs 5 twisted with one another, one also speaks of the stranding of the wire pairs 5 to form a stranding element.

A conductor bundle 1 of the cable thus comprises the wires 3, 4 twisted to form wire pairs 5 and the wire pairs 5 twisted to form the stranding element. The conductor bundle 1 is surrounded by an overall shield 7.

According to the invention, it is now provided that the ratio of a lay length L1 of the conductor bundle 1 to a lay length L2 of a shield 2 is between 0.7 and 1.3, that is $$\frac{\mathrm{L.}1}{\mathrm{L.}2}=0,\mathrm{7th}...1,3.$$

The lay lengths L1 and L2 are particularly preferably identical, however, as far as this is technically possible.

The lay length L1 of the conductor bundle 1 can either be the lay length of the cores 3, 4 ( Fig. 9 ), or the lay length of the stranding 9, i.e. the lay length under which the wire pairs 5 are twisted with one another.

The lay length L2 of the shield 2 is either the lay length with which the pair shield 6 is helically wound around the respective wire pair 5 ( Fig. 9 ), or by the length of the lay with which the overall shield 7 is wrapped around the conductor bundle 1 ( Fig. 7, 8 ). Preferably, these two lay lengths can also be chosen to be identical.

Particularly good transmission properties are achieved when the lay length of the twisting 8 of all wires 3, 4 and / or the lay length of the stranding 9 of all wire pairs 5 and / or the lay length of all pair shields 6 and / or the lay length of the overall shield 7, which are also helical the conductor bundle 1 is wound, are the same.

The cable can be surrounded by a cable sheath 10, for example made of PVC (polyvinyl chloride); A braided shield 11, for example made of tinned copper wires, can be arranged between the cable sheath 10 and the overall shield 7.

Figs. 2 and 3 show other design variants of the cable according to the invention. In Fig. 2 the conductor bundle 1 does not consist of several, but only one twisted pair of wires 5 with pair shielding 6. In Fig. 3 is the wire pair 5 surrounded only by an overall shield 7; a pair shield, as it is in Figs. 1 and 2 is shown, but is omitted. In addition to the outer cable jacket 10, the in Fig. 3 The cable shown has an inner sheath 12 which is arranged between the conductor bundle 1 and the overall shield 7.

Figures 4 and 5 illustrate the positive effects achieved by the cable according to the invention on the transmission properties of a cable.

In Fig. 4 the lay lengths are not coordinated with one another according to the invention. Specifically, the lay length L1 of the stranding element is 11 mm and the lay length L2 of a banding forming the pair shield is 16 mm. The ratio of the lay lengths is thus $$\frac{\mathrm{L.}1}{\mathrm{L.}2}=0,68.$$

In addition to a main peak in the insertion loss (IL) at around 9750 MHz, the attenuation curve in this configuration shows a further, less pronounced peak at around 6600 MHz. However, if the cable is to be used for data transmission in the frequency range up to 9 GHz, such an attenuation curve is disadvantageous in terms of transmission performance.

In order to keep the attenuation curve free of noise and peaks in the relevant frequency range, it is provided according to the invention to select the two stroke lengths L1 and L2 so that their ratio is between 0.7 and 1.3. Fig. 5 shows the insertion loss of a cable according to the invention in which both lay lengths L1 and L2 are each 11 mm, that is $$\frac{\mathrm{L.}1}{\mathrm{L.}2}=1.$$

How to get in Fig. 5 can see well, the relevant frequency range up to 9 GHz is now free of any Attenuation peaks. In addition, due to the coordination of the lay lengths according to the invention, the main peak has been compared with Fig. 4 , shifted to higher frequencies.

Fig. 6 shows a first embodiment of a cable according to the invention. The conductor bundle 1 of the cable comprises the first wire 3 and the second wire 4, which form the wire pair 5. The two wires 3, 4 run parallel to one another, so that the embodiment shown is a “shielded parallel pair” cable. The one in the Figures 6, 7 and 8 However, the cable structure shown can also be used with "shielded twisted pair" cables.

In Fig. 6 the wire pair 5 is surrounded by the pair shield 6, which forms a shield 2 for shielding the first wire 3 and the second wire 4. The pair shield 6 follows an insulation of the first wire 3 or the second wire 4; however, it is also possible for further layers to be arranged between the insulation and pair shielding. The pair shield 6 is in turn followed by the braided shield 11, which consists, for example, of tinned copper wires. Finally, the cable is closed to the outside by a cable sheath 10.

Both the wire pair 5 and the pair shielding 6 can have a lay length: In the case of a "shielded twisted pair" cable, the two wires 3, 4 of the wire pair 5 are twisted together; that length which is required for a twist by 360 ° is then the lay length of the wire pair 5. Likewise, the pair shielding 6 can be wound helically around the conductor bundle 1; the length that is required for a wrap around 360 ° forms the lay length of the pair shielding 6. Alternatively, this lay length can also be specified by the pitch L3 under which the pair shield 6 is wrapped around the conductor bundle 1 ( Fig. 9 ).

This in Fig. 7 The illustrated second embodiment of the cable according to the invention differs from that in Fig. 6 embodiment shown by an inner jacket 12, which surrounds the pair of wires 5; the inner jacket 12 can be made of plastic, preferably PP (polypropylene). Pair shielding as described in Fig. 6 shown, are omitted and only an overall shield 7 is provided, which does not directly surround the pair of wires 5 but is arranged between the inner sheath 12 and the outer cable sheath 10. Similar to the pair shield 6, the overall shield 7 can also be wrapped around the inner jacket 12 with a specific lay length.

Finally shows Fig. 8 a third exemplary embodiment of the cable according to the invention, the conductor bundle 1 of which has two wire pairs 5, each of which comprises either two individual wires 3, 4 arranged in parallel or twisted together. Each pair of wires 5 is wrapped with an associated pair of shielding 6; the two wire pairs 5 themselves are in turn wrapped with an overall shield 7. The lay lengths of the pair shields 6 can be different or, as far as technically possible and sensible, identical. Likewise, the lay length of the overall shield 7 can coincide with or differ from a lay length of a pair of shielding 6. Both the pair shields 6 and the overall shield 7 are surrounded by an associated braided shield 11.

REFERENCE LIST

1

Bundle of conductors

2

Shielding

3

first wire

4th

second wire

5

Wire pair

6th

Pair shielding

7th

Overall shielding

8th

Twist

9

Stranding

10

Cable sheath

11

Braid shield

12th

Inner jacket

L1

Lay length of the conductor bundle

L2

Length of lay of the shield

L3

Shielding slope

Claims (15)

Cable, in particular data cable for the transmission of data in telecommunications, communications or computer technology, comprising at least one conductor bundle (1) and a shield (2) for shielding the conductor bundle (1) and / or the wires (3, 4) of the conductor bundle (1), characterized in that the ratio of a lay length (L1) of the conductor bundle (1) to a lay length (L2) of the shielding (2) is between 0.7 and 1.3. Cable according to Claim 1, characterized in that the ratio of the lay length (L1) of the conductor bundle (1) to the lay length (L2) of the shielding (2) is between 0.8 and 1.2. Cable according to Claim 1 or 2, characterized in that the lay length (L1) of the conductor bundle (1) corresponds to the lay length (L2) of the shielding (2). Cable according to one of Claims 1 to 3, characterized in that the lay length (L1) of the conductor bundle (1) is that of a twisted wire pair (5) of the conductor bundle (1). Cable according to one of Claims 1 to 3, characterized in that the lay length (L1) of the conductor bundle (1) is that of a stranding of wire pairs (5) of the conductor bundle (1). Cable according to one of Claims 4 or 5, characterized in that the screen (2) is a pair screen (6) of the wire pair (5) and / or an overall screen (7) of the conductor bundle (1). Cable according to Claim 6, characterized in that the lay length (L2) of the shielding (2) is that of a banding forming the pair shielding (6) and / or a banding that forms the overall shielding (7). Cable according to one of Claims 4 to 8, characterized in that all lay lengths (L1, L2) are identical. Cable according to one of the preceding claims, characterized in that the cable is a "shielded twisted pair" cable. Cable according to Claim 9, characterized in that a twisted pair of wires (5), in particular with a wire cross-section between 0.02 to 0.35 mm ² , particularly preferably 0.14 or 0.22 mm ² each, and one pair of wires ( 5) surrounding pair shielding (6) is provided, the lay length (L1) of the wire pair (5) and the lay length (L2) of the pair shield (6) each being between 5 and 20 mm, but preferably 9, 10, 11, 15, 16, 17 or 18 mm. Cable according to claim 9, characterized in that a twisted pair of wires (5), in particular with a wire cross-section between 0.02 to 0.35 mm ² , particularly preferably 0.13 mm ² each, and an overall shielding surrounding the pair of wires (5) (7) is provided, the lay length (L1) of the wire pair (5) and the lay length (L2) of the overall shield (7) each between 5 and 15 mm, but preferably 9, 10 or 11 mm. Cable according to Claim 9, characterized in that a stranding element with two twisted wire pairs (5), each surrounded by a pair of shielding (6), and one the Total shielding (7) surrounding the stranding element is provided, the lay length (L1) of the stranding of the two wire pairs (5), the lay length (L2) of the pair screen (6) and the lay length (L2) of the overall screen (7) each between 5 and 15 mm, but preferably 9, 10 or 11 mm. Cable, in particular data cable for the transmission of data in telecommunications, communications or computer technology, comprising at least one conductor bundle (1) and a shield (2) for shielding the conductor bundle (1) and / or the wires (3, 4) of the conductor bundle (1), wherein the cable is designed as a "shielded parallel pair" cable and a wire pair (5) with two parallel wires (3, 4), in particular with a wire cross-section between 0.02 to 0.35 mm ² , in particular preferably of 0.14 or 0.22 mm ² each, and a pair of shielding (6) surrounding the wire pair (5) is provided, characterized in that the lay length (L2) of the pair of shielding (6) is between 3 and 7 mm, preferably but is 5 mm. Cable according to one of the preceding claims, characterized in that the wires (3, 4) of the conductor bundle (1) have the same capacitance per unit length. Cable according to one of the preceding claims, characterized in that the shielding (2) is provided with an aluminum or copper lamination.

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