EP2659494B1 - Electrical line - Google Patents

Description

The invention relates to an electrical line with the features of claim 1.

State of the art

In a complex installation of electrical equipment, for example in motor vehicle technology, in building technology or in systems engineering, a large number of electrical lines is often laid in a confined space. If the installation is changed, ie if existing devices are connected to each other via the electrical lines in a different way, a new device is added or an existing device is removed, it is often necessary to identify the electrical lines individually to make correct connections.

An identification can be carried out, for example, by means of markings, which is applied to a sheathing of the electrical line. For this purpose, labels and color coding are common. Also, electrical identification of an electric wire may be performed by making a circuit through the electric wire. In one embodiment, at one end of the electrical line, a signal generator is connected to two conductors of the electrical line, and at the other end of the electrical line, a signal receiver is connected to the electrical conductors. The signal generated by the signal generator may comprise a DC voltage or a low frequency, preferably in the audible range. When the signal reaches the signal receiver, the electrical line between its two ends is identified.

The connection of different ends of the electrical line can mean a considerable effort in large or difficult to access installations. In addition, during the identification, the electric wire usually can not be used for the equipment of the installation.

It is therefore an object of the invention to provide an electrical line that allows for improved identification. It is a further object of the invention to provide a method of making the electrical lead. The invention solves these objects by means of an electric line with the features of claim 1 and by a method with the method steps of claim. Subclaims give preferred embodiments again.

Disclosure of the invention

An electrical line for connecting two electrical devices comprises a first section having a first impedance and a predetermined first length and a second section having a second impedance and a predetermined second length. In this case, the first section adjoins the second section and the impedances of the adjoining sections are different, so that there is an impedance change in the region of the adjoining sections.

The location of the impedance change can be detected metrologically, for example by means of time domain reflectometry. In this case, the total length of the line and the lengths of the two sections can be determined. If the determined lengths match predetermined lengths of a line to be searched, the line is found.

Advantageously, in some embodiments, the electrical line may remain operational during the described identification for connecting two electrical devices. In addition, the identification can be carried out quickly and usually requires only one access to one of the ends of the electrical line. If the line is individually coded by means of the location of the impedance change and sufficiently connected to a predetermined environment, a device connected to the connection can check that it is in the predetermined environment. A function or use of the device can thus be bound by the described design of the electrical connection to the environment.

The electrical line can also have one or more further sections with predetermined lengths, wherein each two adjacent sections have different impedances. As a result, an identification security of the connection can be increased. Further, it is also possible to identify an electrical line having a branch. An identification of the electrical line can be made at any end.

In the case of more than two sections, pairs adjacent to each other along the line may have alternating impedances. Although a magnitude of the impedance change may be determined by time domain reflectometry by comparing the pulse strengths, it is not necessary to perform the identification of the electrical line based on a variety of different impedance variations. Rather, it is sufficient to use two different impedances alternately along the electrical line, which can simplify the manufacturability of the line and thereby help to reduce manufacturing costs.

The electrical line can comprise two conductors running along the line, between which a dielectric is arranged, dielectrics of adjoining sections of the line having different permittivities. This makes it possible to bring about the different impedances on the adjacent sections of the electrical line, without changing the conductors themselves. A manufacturability of the electrical line based on a known electrical line can be simplified.

One of the dielectrics may include high permittivity particles. Due to the permissive particles, it is possible for a dielectric constant of the dielectric to be changed, so that the impedance of the line in the region of the dielectric can be controlled in a targeted manner by admixing the particles.

Along the two sections, two media of different permittivities can be mixed in different proportions, so that the Dielectric constant along the sections on the mixing ratio can be influenced.

Preferably, the conductors are twisted together. Twisted electrical conductors are inexpensive to produce and have a sufficient signal transmission behavior for many applications. The dielectric in the region of the conductors can be applied during or after the production of the electrical line. An identifiability of an electrical line can thus be adapted or changed optionally before, during or only after the laying of the electrical line in an installation.

Preferably, the area of the adjoining portions is less long than a diameter of the electric wire. Thereby, it can be ensured that a pulse reflected from the impedance change between the adjoining sections is steep flank enough to allow a unique measurement. The identifiability of the electrical line can thereby be increased.

A method of fabricating an electrical lead includes steps of providing two conductors running along the lead, providing a plurality of dielectrics having different permittivities, and mounting the dielectrics on predetermined portions along the lead between the leads, such that adjacent portions of predetermined lengths have different impedances exhibit.

In this way, the electrical line described above can be produced inexpensively. In this case, the method is sufficiently flexible to produce a multiplicity of variations of the electrical lines produced, so that an individual identifiability of a manufactured electrical line can be ensured. In one embodiment, only two different Dielectrics used, one of which is an already existing ambient material, such as air. As a result, the production can be simplified and manufacturing costs can be saved.

In one embodiment, the two conductors are twisted together and at least one of the dielectrics is mounted after twisting. A manufacturing device for lines with twisted conductors therefore does not have to be adapted consuming to produce the described electrical line can.

Figur 1

eine Installation mehrerer Geräte;

Figur 2

eine Schnittansicht eines Koaxialkabels für die Installation aus Figur 1;

Figur 3

eine Seitenansicht des Koaxialkabels aus Figur2;

Figur 4

eine Seitenansicht eines Twisted-Pair-Kabels für die Installation aus Figur1; und

Figur 5

ein Ablaufdiagramm eines Verfahrens zur Herstellung der Kabel aus Figuren 3 oder 4

darstellt.In the following, the invention will be described in more detail with reference to the attached figures, in which:

FIG. 1

an installation of several devices;

FIG. 2

a sectional view of a coaxial cable for installation FIG. 1 ;

FIG. 3

a side view of the coaxial cable Figur2 ;

FIG. 4

a side view of a twisted pair cable for installation Figur1 ; and

FIG. 5

a flow diagram of a method for producing the cable Figures 3 or 4

represents.

Detailed description of embodiments

FIG. 1 shows an installation 100 of several devices, which are connected to each other by means of an electrical line 110, on board a motor vehicle 105. This is a schematic diagram; the electric wire 110 described in more detail below is not limited to use within the motor vehicle 105. Rather, the electrical lead 110 can basically be used within any electrical installations.

In one embodiment, one purpose of the electrical lead 110 is to extend electrical identifiability of the electrical lead to an environment of the lead. For this purpose, the electrical line is preferably mechanically connected to the environment that replacement or manipulation of the electrical line is very expensive. For example, the electrical line 110 can be arranged inside a cable harness on or in the motor vehicle 105. In another embodiment, the electrical lead 110 may be laid within a building as a flush-mounted cable or screed.

The two in FIG. 1 illustrated devices 115, 120 may be any electrical devices. In the illustrated embodiment, it is assumed that identification of the electrical line 110 is performed by the first device 115. For this, the second electrical device 120 can also be dispensed with. In alternative embodiments, the identification may also be performed by the second electrical device 120 or another device connected to the electrical line 110. The further device may be, for example, a service or diagnostic device, which is additionally or in exchange for one of the devices 115, 120 electrically connected to the line 110.

The electrical line 110 comprises a first section 125 and a second section 130. The first section 125 has a length L1 and an impedance Z1 and leads from the first device 115 to the second section 130. The second section 130 has a length L2 and an impedance Z2 and leads from the first portion 125 to the second electrical device 120. An impedance transition 135 is formed at the location of the line 110, at the first portion 125 adjacent to the second portion 130.

To identify the electrical line 110, the first device 115 comprises a signal generator 140 and a scanner 145, both of which are connected to the same end of the electrical line 110 on the first section 125. For identification of the line 110, in particular a length of the first section 125, a length of the second section 130 and optionally a size of the impedance transition 135 are determined by the first device 115. In an alternative embodiment, the first electrical device 115 may also be connected to another location of the electrical connection 110, wherein the connection preferably takes place at a determinable distance from the impedance transition 135.

• Mittels des Signalgenerators 140 wird ein erster elektrischer Impuls erzeugt und an das Ende der elektrischen Leitung 110 gelegt. Die Abtasteinrichtung 145 kann diesen ersten Impuls erfassen. Der erste Impuls durchläuft den ersten Abschnitt 125 nach rechts und erfährt eine teilweise Reflexion am Impedanzübergang 135. Der reflektierte Teil des ersten Impulses bildet einen zweiten Impuls, der durch den ersten Abschnitt 125 nach links zurück läuft und durch die Abtasteinrichtung 145 in Zeitpunkt und Amplitude bestimmt werden kann. Der Teil des ersten Impulses, der am Impedanzübergang 135 nicht reflektiert wurde, bildet einen dritten Impuls, der den zweiten Abschnitt 130 nach rechts entlang läuft. Am Ende des zweiten Abschnitts 130 wird der Impuls am zweiten Gerät 120 ebenfalls teilweise reflektiert und bildet einen vierten Impuls. Zur Verbesserung der Reflektion zwischen dem Ende des zweiten Abschnitts 130 und dem zweiten Gerät 120 kann es vorteilhaft sein, in diesem Bereich einen weiteren Impedanzübergang herzustellen. Beispielsweise kann das elektrische Gerät 120 von der elektrischen Leitung 110 getrennt öder Leiter der elektrischen Leitung 110 am zweiten elektrischen Gerät 120 miteinander verbunden werden. Der vierte Impuls durchläuft den zweiten Abschnitt 130 nach links bis zum Impedanzübergang 135, wo er erneut teilweise reflektiert wird. Der Teil des vierten Impulses, der nicht reflektiert wird, bildet einen fünften Impuls, der durch den ersten Abschnitt 125 nach links bis zum ersten Gerät 115 läuft und dort von der Abtasteinrichtung 145 in Zeitpunkt und Amplitude erfasst werden kann.

To identify the electrical connection 110, the procedure is as follows:

• By means of the signal generator 140, a first electrical pulse is generated and applied to the end of the electrical line 110. The scanner 145 may detect this first pulse. The first pulse passes rightward through the first portion 125 and undergoes partial reflection at the impedance transition 135. The reflected portion of the first pulse forms a second pulse that travels leftward through the first portion 125 and is determined by the sampler 145 in timing and amplitude can be. The portion of the first pulse that was not reflected at the impedance transition 135 forms a third pulse that traverses the second portion 130 to the right. At the end of the second section 130, the pulse on the second device 120 is also partially reflected and forms a fourth pulse. To improve the reflection between the end of the second section 130 and the second device 120, it may be advantageous to produce a further impedance transition in this area. For example, the electrical device 120 can be connected to one another from the electrical line 110 or the conductor of the electrical line 110 at the second electrical device 120. The fourth pulse passes through the second portion 130 leftward to the impedance transition 135, where it is again partially reflected. The portion of the fourth pulse that is not reflected forms a fifth pulse that passes through the first portion 125 to the left to the first device 115 where it can be detected by the sampler 145 in timing and amplitude.

From the time intervals of the first pulse to the other pulses sampled at the sampling device 145, the length of the first section 125 and the length of the electrical line 110 are determined with knowledge of a signal propagation speed along the electrical line 110. By subtraction, the length of the second section 130 can be determined from these lengths.

The electrical line 110 is such that the lengths L1, L2 of the sections 125 and 130 are characteristic of the line 110. If the determined lengths L1, L2 of the sections 125 and 130 coincide with predetermined lengths, the electrical line 110 is identified. Assuming that the electric wire 110 is inseparably connected to the motor vehicle 105 - or any other environment - it can be determined in this way by the device 115, whether it is on board a predetermined motor vehicle 105 or not. From this determination, an operating mode or an operating state of the electrical device 115 can be derived. For example, operation of the device 115 onboard a non-predetermined motor vehicle 105 may be denied.

The described determination of the lengths of sections 125 and 130 of electrical lead 110 can be generalized to any number and arrangement of contiguous sections 125, 130 of connection 110. Branches and even loops between sections are not an obstacle to the described identification. Of course, the particular lengths of the sections 125, 130 of the electrical connection 110 are different or lie in different arrangements, depending on at which point of the electrical line 110, the first device 115 is connected.

FIG. 2 FIG. 12 is a sectional view of a coaxial cable 200 not according to the present invention corresponding to the electric wire 110 FIG. 1 , The coaxial cable 200 includes an inner conductor 205 radially surrounded by an inner insulating member 210. From the inner insulating element 210, a plurality of webs 215 radially extend up to an outer insulating element 220. Between the webs 215 and the insulating elements 210, 220 are chambers 225 educated. The outer insulating member 220 is enclosed in the radial direction by an outer conductor 230, which in turn is enclosed by a protective jacket 235.

The chambers 225 are filled with air or other gas in known coaxial cables (e.g., AirCom Plus). The medium accommodated in the chambers 225 acts as a dielectric, which is arranged between the conductors 205 and 230 and which influences an impedance of the coaxial cable 200 via its permittivity. If a material which has a different permittivity than air or the other gas is introduced into the chambers 225 on an axial section of the coaxial cable, the coaxial cable 200 has a changed impedance on this section. Accordingly, impedance transitions result to adjacent axial portions of the coaxial cable 200. Alternatively, the percentage of different media in the sections may vary, for example, by changing the blowing agent concentration in an insulating foam that forms the dielectric of the cable.

FIG. 3 FIG. 12 shows a side view of the coaxial cable 200 not covered by the present invention FIG. 2 , In the axial direction, the coaxial cable 200 is divided into a number of sections 310 to 370. In the sections 350 to 370, which lie in pairs between the sections 310 to 340, a dielectric is filled into the chambers 225, the permittivity of which differs from the dielectric in the chambers 225 of the sections 310 to 340. Along an axial extent of the coaxial cable 200, impedance transitions thus each result between two mutually adjacent sections 310 to 370.

The coaxial cable 200 may be filled with different dielectrics in the chambers 225 during manufacture at regular or irregular intervals. A first dielectric may include air or the insulating foam, while a second dielectric may comprise a substance having particles of high permittivity, such as ceramic, added.

FIG. 4 shows a side view of a twisted pair cable 400 corresponding to the electrical line 110 from FIG. 1 , According to the presentation of FIG. 2 For example, the twisted pair cable 400 is connected between the device 115 and the other device 120. The twisted-pair cable 400 includes two twisted-together conductors 403, 405 and is subdivided into sections 410 to 450, wherein the sections 440 and 450 lie in pairs between the sections 410 to 430.

In sections 440 and 450, the twisted pair cable 400 is surrounded by a substance 460 that is coated with high permittivity particles 470. The substance 460 is preferably a plastic or an adhesive, for example a hot-melt adhesive or a two-component adhesive, for example based on polyester, acrylic or epoxide.

In an alternative embodiment, the substance 460 can also be formed, for example, by a fastening clip, by means of which the twisted pair cable 400 can be clamped in and / or secured to an environment.

In sections 440 and 450, the substance 460 with the particles 470 acts as a dielectric, so that the impedance of the twisted pair cable 400 in these sections is changed from the other sections 410 to 430. At the junctions between adjacent sections 410-4, there are impedance transitions at which a pulse passing through the twisted pair cable 400 is partially reflected.

FIG. 5 FIG. 12 shows a flow chart of a method 500 for producing an electrical lead 110 according to the cables 300 and 400, respectively Figures 3 or 4.

In a first step 505, conductors are provided which are to run later along the line 110, 200 and 400, respectively. In the case of the coaxial cable 200, the conductors include the inner conductor 205 and the outer conductor 230; in the case of the twisted pair cable 400, the conductors 403 and 405 includes. It is also possible for more than two conductors 205, 230, 403, 405 to be included in the electrical line 110, which are provided in step 505 and subsequently installed in the electrical line 110, 200, 400.

In a following step 510 several dielectrics with different permittivities are provided. In one embodiment, only two different dielectrics are used, one of which comprises a medium which is present anyway in the region of the provided conductors 205, 230, 403, 405. In particular, this medium may comprise air, an insulating foam, a plastic or a predetermined arrangement of plastic with air. In another embodiment, different dielectrics are provided by adding the same substance 460 to different levels of high permittivity particles 470. Different particles 470 may also be used.

In a following step 515, the dielectrics are mounted on predetermined sections 125, 130, 310-370, 410-450 along the line 110, in each case between the conductors 205, 230, 403, 405 such that adjacent sections 125, 130, 310- 370, 410-450 predetermined lengths L1, L2 have different impedances Z1, Z2. The lengths L1, L2 of the sections 125, 130, 310-370, 410-450 may, in one embodiment, be random.

The method 500 is over. In the manufacture of electrical lines 110, 200, 400 on an industrial scale usually a very long or even no further limited length of the electric wire 110 is produced, which cut in a final step of the method 500 suitable and optionally provided at the ends with an electrical contact becomes.

Claims (9)

1. Electrical twisted-pair line (110) for connecting two electrical devices, wherein the electrical line (110) comprises the following:

   - two electrical conductors (403, 405) which are twisted together and which are subdivided into a first section (125) with a first impedance (Z13) and a predetermined first length (L1) and into a second section (130) with a second impedance (Z2) and a predetermined second length (L2);

   - wherein the first section (125) adjoins the second section (130);

   - wherein the impedances of the sections (125, 130) which adjoin one another are different, so that there is a change (135) in impedance in the region of the sections (125, 130) which adjoin one another,

   - and the line (110) is encoded by means of the location of the change (135) in impedance in order to ensure the ability to individually identify the line (110) by means of time domain reflectometry.
2. Electrical line (110) according to Claim 1, characterized by one or more further sections with predetermined lengths, wherein in each case two sections (125, 130) which adjoin one another have different impedances (Z1, Z2).
3. Electrical line (110) according to Claim 2, characterized by a plurality of sections (125, 130) which adpein one another in pairs and have alternating impedances (Z1, Z2) along the line (110).
4. Electrical line (110) according to one of the preceding claims, characterized by two conductors (403, 405, 205, 230) which run along the line (110) and between which a dielectric (460) is arranged, wherein dielectrics of sections (125, 130) of the line (110) which adjoin one another have different permittivities.
5. Electrical line (110) according to Claim 4, characterized in that one of the dielectrics (460) comprises particles (470) of high permittivity.
6. Electrical line (110) according to Claim 4 or 5, characterized in that two media of different permittivities are mixed with one another in different ratios in the sections (125, 130).
7. Electrical line (110) according to one of the preceding claims, characterized in that the region (135) of the sections (125, 130) which adjoin one another has a length which is shorter than a diameter of the line (110).
8. Method (500) for producing an electrical line (110) according to one of the preceding claims, characterized by the following steps:

   - providing (505) two conductors (205, 230, 403, 405) which run along the line;

   - providing (510) a plurality of dielectrics with different permittivities; and

   - fitting (515) the dielectrics on predetermined sections (125, 130) along the line (110, 200, 400) in each case between the conductors (205, 230, 403, 405) in such a way that sections (125, 130), which adjoin one another, of predetermined lengths (L1, L2) have different impedances.
9. Method 500 according to Claim 1, characterised in that at least one of the dielectrics is fitted only after the twisting operation.

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