Crosstalk shielding device for connection strips in telecommunications and data communication

A shielding device for connection strips in telecommunications and data engineering has a number of shielding plates and at least one base rail allocated to the shielding plates. To simplify the process of fitting the shielding device inside a connection strip, the shielding plates (2) and the base rail (3) are integrally formed from a metal sheet (28), and each shielding plate (2) is connected to the base rail (3) via a narrow web (4) and is arranged rotated through approximately 90° with respect to the base rail (3).

FIELD OF THE INVENTION

The invention relates to a shielding device for connection strips in telecommunications and data engineering, comprising a number of shielding plates and at least one base rail allocated to the latter.

BACKGROUND OF THE INVENTION

A shielding device of the generic type is already known from the connection strip disclosed in U.S. Pat. No. 5,160,273. Here, the problem of crosstalk between adjacent insulation-piercing terminal contact elements of the connection strip is solved by the insertion of a multiplicity of electrically conductive shielding plates between the individual pairs of insulation-piercing terminal contact elements. The problem of crosstalk occurs when transmitting large volumes of information via electrical lines, the information being transmitted at high frequencies. Transmitting at high frequencies produces radiation and interference between adjacent lines, particularly when these lines are arranged close beside one another in the connection strip. Electrically conductive shielding plates are inserted between a pair of insulation-piercing terminal contact elements, the spacing between two adjacent pairs of insulation-piercing terminal contact elements being larger than the spacing between adjacent insulation-piercing terminal contact elements in a pair. The shielding plates are in this case inserted between pairs of insulation-piercing terminal contact elements in slots which extend transversely to the longitudinal direction of the plastic body of the connection strip, and contact the base rail situated in the longitudinal direction inside the plastic body. A disadvantage of this is that, when fitting the component into the plastic body, it is first necessary to fit the base rail, which has contact tongues for contacting the individual shielding plates, and that it is subsequently necessary to push the individual shielding plates into the connection strip. Consequently, the complexity of assembly is relatively high in order to provide the connection strip with the shielding device for high transmission rates in telecommunications and data engineering.

SUMMARY AND OBJECTS OF THE INVENTION

The invention is therefore based on the object of improving the shielding device of the generic type in order to simplify assembly.

To achieve this object, the invention provides for the shielding plates and the base rail to be integrally formed from a metal plate, and for each shielding plate to be connected to the base rail via a narrow web and arranged rotated through approximately 90° with respect to the base rail. The shielding device according to the invention thus forms an integral component which is made of metallic material and which, during assembly of a connection strip for telecommunications and data engineering, is inserted into the plastic housing of the connection strip with its base rail, and its shielding plates, which are integrally connected to the base rail, are guided into all the preformed slots inside the connection strip at the same time. This simplifies assembly considerably.

In a further embodiment of the invention, the spacings between the shielding plates on a base rail may be designed to be different from one another. This enables a shielding plate to be matched to different applications.

The invention also relates to a method of producing the shielding device wherein a number of shielding plates and a base rail supporting the latter, as well as webs connecting the shielding plates to the base rail, are integrally formed from a metal sheet. The shielding plates are subsequently rotated in the region of the webs through approximately 90° with respect to the base rail.

According to a further aspect of the invention, a connection strip is provided for telecommunications and data engineering. The connection strip has insulation-piercing terminal contact elements arranged in a plastic housing, and shielding plates arranged between said insulation-piercing terminal contact elements. At least one ground rail is allocated to the shielding plates. The shielding plates and the base rail are integrally formed from a metal sheet. Each shielding plate is connected to the base rail via a narrow web and is arranged rotated through 90° with respect to the base rail.

According to still another aspect of the invention, a process for using a shielding device comprising a base rail and shielding plates is provided wherein the shielding plates are integrally formed on the base rail and are rotated through 90° with respect to the base rail. The device si used as a shielding inside a connection strip for high transmission rates in telecommunications and data engineering applications.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in particular, in the exemplary embodiment, the shielding device1comprises seven flat, essentially U-shaped shielding plates2, a base rail3and seven connection webs4, which connect the individual shielding plates2to the base rail3. The shielding device1is made of conductive metallic material and is integrally formed, in particular punched, with the shielding plates2, the base rail3, and the connection webs4, from a metal sheet28. The sheet metal28is particularly copper, copper alloys, steel or aluminum. The shielding plates2and the base rail3with the connection webs4are initially in the same plane as the metal sheet28(as shown inFIG. 4). In a work step which follows the cutting-out process, the individual shielding plates2are rotated in the region of their5connection webs4through 90° with respect to the base rail3. A hole5in the base rail3is associated with each shielding plate2close to the connection web4, and this hole5is used for adjustment during the4production process. The metal sheet28may also be a metalized plastic strip or the like.

In the view of how the shielding device1is processed, shown inFIG. 4, the individual shielding plates2are of U-shaped design, a roughly rectangular shielding panel6adjoining the connection web4and being provided with two prong-like shielding forks7at the end remote from the connection web4. These shielding forks7are stepped by means of a shoulder8which tapers the cross section so that they are matched to the internal cross section of the connection strip11.

FIG. 4shows the metal sheet28with cut-out or punched-out shielding plates2of width B with a mean spacing X between one another and with the cut-out or punched-out base rail3with the holes5which are used for adjustment during production. The length of the metal sheet28corresponds to the number of shielding plates2of width B plus the cut gaps.

FIG. 5shows the shielding plates2which are rotated through 90° with respect to the base rail3and are normally at a distance X from one another. To achieve a shorter distance X′, a fold9is introduced into the base rail3, as shown inFIG. 8.

The shielding device1is used for shielding the individual insulation-piercing terminal contact elements10inside a connection strip11for high transmission rates in telecommunications and data engineering. Such a connection strip11, having a plurality of insulation-piercing terminal contact elements10arranged in pairs, is illustrated and described in more detail in DE 43 25 952 C2 (and in U.S. Pat. No. 5,494,461). U.S. Pat. No. 5,494,461 is hereby incorporated by reference. The connection strip11is illustrated inFIGS. 6 to 9and is described in more detail below with respect to the shielding device1used.

The connection strip11comprises a plastic housing12made of an upper part13and a lower part14which are latched to one another by means of latching openings15in the upper part13and latching lugs16in the lower part14. Terminal slots17are formed in the upper part13and have integrally formed terminal lugs18and terminal webs19which serve to hold the insulation-piercing terminal contact elements10. The latter are formed from sheet-like flat material and comprise two contact webs21enclosing a contact slot20between them. A base web22is adjoined by contact fingers23which merge into spring contacts24. Two pairs of insulation-piercing terminal contact elements10are respectively arranged close beside one another, the spacing D between two adjacent pairs of insulation-piercing terminal contact elements10being considerably larger than the spacing d between insulation-piercing terminal contact elements10which are close beside one another, as can be seen inFIG. 6. The individual shielding plates2of the shielding device1are inserted into the total of seven wider cross-sectional regions25of the connection strip11, as shown by dashed lines inFIGS. 6 and 7and by solid lines inFIGS. 8 and 9.

To insert the base rail3with the individual shielding plates2into the housing12of the connection strip11, the upper part13in the exemplary embodiment contains seven chambers26with respective transverse slots27into which the individual shielding plates2are pushed. The base rail3is situated in a longitudinal slot21in the bottom region of the lower part14, as shown inFIGS. 7 and 9. The shielding panels6and shielding forks7, which adjoin the latter, of the individual shielding plates2essentially take up the whole of the cross section of the interior of the connection strip11, as shown inFIG. 9in particular, and thus separate the individual pairs of insulation-piercing terminal contact elements10in such a manner that greater5crosstalk attenuation is achieved for high transmission rates as a result of the electrically conductive shielding plates2. The use of the large-area electrically conductive shielding plates2in the connection strip11does not require the physical volume of the connection strip to be enlarged, nor any greater expense to produce it.

The shielding device1does not require any grounding. It is important only that the individual shielding plates2are conductively connected to one another. This is achieved by means of the base rail3, which is common to all the shielding plates2. The shielding plates2influence the electrical field in such a way that the influence charging of an insulation-piercing terminal contact element10is reduced in the adjacent insulation-piercing terminal contact element10, and the interference voltage is thus small. This produces a relatively high signal-to-noise ratio. The signal-to-noise ratio becomes higher, with the result that higher frequencies can be transmitted without the adjacent lines of the insulation-piercing terminal contact elements10having an adverse effect on one another.

The number of shielding plates2in a shielding device1depends on the number of pairs of insulation-piercing terminal contact elements10. In the exemplary embodiment, an 8-pair module is illustrated, which has seven chambers26for a total of seven shielding plates2. Common pairings are 4/3, 8/7, 10/9, 12/11, 16/15, 20/19, 24/23 and 25/24, where the number of pairs of insulation-piercing terminal contact elements10and the number of shielding plates2are indicated in each case.

For a HIGHBAND® brand8connection strip11, the standard spacing X between the shielding plates2is X=12.6 mm. However, for a HIGHBAND® brand10connection strip11, for example, the spacing is X′=9.6 mm. For this, the folds9are introduced into the base rail3between each of the individual shielding plates2. This spacing cannot be achieved by directly punching the shielding device1out of a metal sheet28, since the width B of the individual shielding plate2needs to be around 12 mm on account of the width of the connection strip11. Hence, for a HIGHBAND® brand8connection strip11,10the dimensions width B=12.6 mm and spacing X=12.6 mm complement one another well. For a narrower spacing X′, however, folds9are necessary; these may be replaced by any other kind of means for shortening the length of the base rail3.