Patent Abstract:
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 ).

Full Description:
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. 
     The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective illustration of the shielding device; 
         FIG. 2  is a front view of the device of  FIG. 1 ; 
         FIG. 3  is a plan view of the device of  FIG. 1 ; 
         FIG. 4  is a plan view of a metal sheet having punched-out shielding plates and the base rail; 
         FIG. 5  is a perspective illustration, corresponding to  FIG. 4 , of a part of the shielding device having a folded base rail; 
         FIG. 6  is a side view of a connection strip; 
         FIG. 7  is a cross sectional view along the line A—A in  FIG. 6 ; 
         FIG. 8  is a plan view of the connection strip shown in  FIG. 6 ; and 
         FIG. 9  is a cross sectional view along the line B—B in  FIG. 8   
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings in particular, in the exemplary embodiment, the shielding device  1  comprises seven flat, essentially U-shaped shielding plates  2 , a base rail  3  and seven connection webs  4 , which connect the individual shielding plates  2  to the base rail  3 . The shielding device  1  is made of conductive metallic material and is integrally formed, in particular punched, with the shielding plates  2 , the base rail  3 , and the connection webs  4 , from a metal sheet  28 . The sheet metal  28  is particularly copper, copper alloys, steel or aluminum. The shielding plates  2  and the base rail  3  with the connection webs  4  are initially in the same plane as the metal sheet  28  (as shown in  FIG. 4 ). In a work step which follows the cutting-out process, the individual shielding plates  2  are rotated in the region of their  5  connection webs  4  through 90° with respect to the base rail  3 . A hole  5  in the base rail  3  is associated with each shielding plate  2  close to the connection web  4 , and this hole  5  is used for adjustment during the  4  production process. The metal sheet  28  may also be a metalized plastic strip or the like. 
     In the view of how the shielding device  1  is processed, shown in  FIG. 4 , the individual shielding plates  2  are of U-shaped design, a roughly rectangular shielding panel  6  adjoining the connection web  4  and being provided with two prong-like shielding forks  7  at the end remote from the connection web  4 . These shielding forks  7  are stepped by means of a shoulder  8  which tapers the cross section so that they are matched to the internal cross section of the connection strip  11 . 
       FIG. 4  shows the metal sheet  28  with cut-out or punched-out shielding plates  2  of width B with a mean spacing X between one another and with the cut-out or punched-out base rail  3  with the holes  5  which are used for adjustment during production. The length of the metal sheet  28  corresponds to the number of shielding plates  2  of width B plus the cut gaps. 
       FIG. 5  shows the shielding plates  2  which are rotated through 90° with respect to the base rail  3  and are normally at a distance X from one another. To achieve a shorter distance X′, a fold  9  is introduced into the base rail  3 , as shown in  FIG. 8 . 
     The shielding device  1  is used for shielding the individual insulation-piercing terminal contact elements  10  inside a connection strip  11  for high transmission rates in telecommunications and data engineering. Such a connection strip  11 , having a plurality of insulation-piercing terminal contact elements  10  arranged 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 strip  11  is illustrated in  FIGS. 6 to 9  and is described in more detail below with respect to the shielding device  1  used. 
     The connection strip  11  comprises a plastic housing  12  made of an upper part  13  and a lower part  14  which are latched to one another by means of latching openings  15  in the upper part  13  and latching lugs  16  in the lower part  14 . Terminal slots  17  are formed in the upper part  13  and have integrally formed terminal lugs  18  and terminal webs  19  which serve to hold the insulation-piercing terminal contact elements  10 . The latter are formed from sheet-like flat material and comprise two contact webs  21  enclosing a contact slot  20  between them. A base web  22  is adjoined by contact fingers  23  which merge into spring contacts  24 . Two pairs of insulation-piercing terminal contact elements  10  are respectively arranged close beside one another, the spacing D between two adjacent pairs of insulation-piercing terminal contact elements  10  being considerably larger than the spacing d between insulation-piercing terminal contact elements  10  which are close beside one another, as can be seen in  FIG. 6 . The individual shielding plates  2  of the shielding device  1  are inserted into the total of seven wider cross-sectional regions  25  of the connection strip  11 , as shown by dashed lines in  FIGS. 6 and 7  and by solid lines in  FIGS. 8 and 9 . 
     To insert the base rail  3  with the individual shielding plates  2  into the housing  12  of the connection strip  11 , the upper part  13  in the exemplary embodiment contains seven chambers  26  with respective transverse slots  27  into which the individual shielding plates  2  are pushed. The base rail  3  is situated in a longitudinal slot  21  in the bottom region of the lower part  14 , as shown in  FIGS. 7 and 9 . The shielding panels  6  and shielding forks  7 , which adjoin the latter, of the individual shielding plates  2  essentially take up the whole of the cross section of the interior of the connection strip  11 , as shown in  FIG. 9  in particular, and thus separate the individual pairs of insulation-piercing terminal contact elements  10  in such a manner that greater  5  crosstalk attenuation is achieved for high transmission rates as a result of the electrically conductive shielding plates  2 . The use of the large-area electrically conductive shielding plates  2  in the connection strip  11  does not require the physical volume of the connection strip to be enlarged, nor any greater expense to produce it. 
     The shielding device  1  does not require any grounding. It is important only that the individual shielding plates  2  are conductively connected to one another. This is achieved by means of the base rail  3 , which is common to all the shielding plates  2 . The shielding plates  2  influence the electrical field in such a way that the influence charging of an insulation-piercing terminal contact element  10  is reduced in the adjacent insulation-piercing terminal contact element  10 , 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 elements  10  having an adverse effect on one another. 
     The number of shielding plates  2  in a shielding device  1  depends on the number of pairs of insulation-piercing terminal contact elements  10 . In the exemplary embodiment, an 8-pair module is illustrated, which has seven chambers  26  for a total of seven shielding plates  2 . 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 elements  10  and the number of shielding plates  2  are indicated in each case. 
     For a HIGHBAND® brand  8  connection strip  11 , the standard spacing X between the shielding plates  2  is X=12.6 mm. However, for a HIGHBAND® brand  10  connection strip  11 , for example, the spacing is X′=9.6 mm. For this, the folds  9  are introduced into the base rail  3  between each of the individual shielding plates  2 . This spacing cannot be achieved by directly punching the shielding device  1  out of a metal sheet  28 , since the width B of the individual shielding plate  2  needs to be around 12 mm on account of the width of the connection strip  11 . Hence, for a HIGHBAND® brand  8  connection strip  11 ,  10  the dimensions width B=12.6 mm and spacing X=12.6 mm complement one another well. For a narrower spacing X′, however, folds  9  are necessary; these may be replaced by any other kind of means for shortening the length of the base rail  3 . 
     While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Technology Classification (CPC): 8