Abstract:
A plug connector for printed circuit boards includes a number of contact elements positioned in a housing. The contact elements each have two connection ends and an intermediate contact positioned between the two ends, where one connection end is in the form of an insulation displacement contact for connecting wires. The insulation displacement contacts are supported on the housing, so that the contact elements are held captively in the housing when connection forces act on the insulation displacement contacts.

Description:
This application is a Continuation of U.S. Ser. No. 11/547,453, filed Sep. 18, 2008, now U.S. Pat. No. 7,717,732, which is a National Stage Application of PCT/EP2005/002968 filed 19 Mar. 2005, which claims benefit of Serial No. 10 2004 017 605.1, filed 7 Apr. 2004 in Germany and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications. 
    
    
     FIELD 
     The invention relates to a plug connector for printed circuit boards and also to a distributor connection module produced therewith. 
     BACKGROUND 
     DE 38 28 904 C2 discloses a plug connector for printed circuit boards, comprising contact elements which are electrically conductively connected to the conductor tracks on the printed circuit board and comprising a plug socket which is provided with mating contacts, where the contact elements are in the form of electrically conductive flat metal strips which are provided with angled strip portions to pass through receiving openings produced on the printed circuit board, are used to make contact with one of the conductor tracks, are electrically conductively connected to the conductor tracks and are fitted on an edge region of the printed circuit board, where the plug socket is provided with a receiving opening for the purpose of plugging it onto the edge region of the printed circuit board and with the mating contacts for the purpose of making contact with the metal strips, each metal strip having two angled resilient strip portions, provided with longitudinal slots and with lateral latching lugs for engaging behind the printed circuit board, for the purpose of putting it through and latching it into two passage holes which have been made in the region of the conductor track of the printed circuit board and serve as receiving openings. The drawback of the known plug connector is the relative complexity of making contact with the printed circuit board. 
     DE 100 29 649 C2 discloses a distributor connection module for telecommunications and data technology, comprising a housing in which input and output contacts for connecting lines or wires are arranged such that they are externally accessible, where the housing is designed to have a cavity which contains a printed circuit board having functional elements which is supported in the housing, the functional elements being arranged electrically between the input and output contacts, and the input contacts and the output contacts being arranged on opposite end faces of the housing. In this arrangement, the input and output contacts may be in the form of insulation displacement contacts which are each designed to have a fork-like contact which can be used to produce a force-fitting electrical connection for the functional elements. The printed circuit board has contact pads which are preferably on the top and bottom of the printed circuit board. These force-fitting connections are much more tolerant to production and assembly tolerances than solder connections. This means that contact can be made simultaneously with all of the insulation displacement contacts by latching the fork-like contacts onto the contact pads. In addition, this type of contact allows simple disassembly, for example if it is necessary to replace a faulty printed circuit board. To produce the distributor connection module, the printed circuit board with the functional elements is pushed into a first housing portion, and a second housing portion, carrying the input contacts, is latched on. To this end, the insulation displacement contacts are fixed to the housing, whereas the tuning fork contacts are free. Since large forces may arise when the insulation displacement contacts are subsequently connected up, it is additionally possible to latch a plastic-like retaining or support element onto the printed circuit board over the entire width of the printed circuit board, which fixes the fork-like contacts on the printed circuit board. 
     In addition, the printed document discloses the practice of arranging a respective externally accessible isolating contact between an input contact and an output contact, the isolating contact being arranged on the bottom of the printed circuit board. This results in a relatively complex assembly operation, since the isolating contacts need to be clamped between the printed circuit board and the housing. 
     DE 101 11 571 A1 discloses an electrical contact element for a plug connector arrangement. The contact element has an insulation displacement region at one end and a tuning fork contact at the other end. To increase the elasticity of the tuning fork contact, the contact-making arms are connected directly to the lower region of a lateral connecting piece of the double insulation piercing connecting devices and are then bent at an angle toward the center of the contact element, so that an extended spring movement results. 
     DE 38 06 263 A1 and DE 199 45 412 A1 each disclose a plug connector for printed circuit boards, comprising a number of contact elements, where the contact elements each have two connection ends, where one connection end is in the form of an insulation displacement contact for connecting wires and the other connection end is in the form of a tuning fork contact for making contact with pads on a printed circuit board, and a plastic housing into which the insulation displacement contacts of the contact elements can be inserted, where the insulation displacement contact and the tuning fork contact are arranged so as to be twisted with respect to one another and at least one lower edge of the insulation displacement contact is supported on the plastic housing, so that the contact elements are held captively in the plastic housing when connection forces act on the insulation displacement contacts, the plastic housing comprising at least one chamber-like region, and the tuning fork contacts being fully accommodated in the longitudinal direction by the plastic housing. 
     SUMMARY 
     Against the background of this known prior art, the invention is based on the technical problem of providing a plug connector which can be used to construct a distributor connection module having isolating contacts which is easier to manufacture from a production point of view and also of providing an associated distributor connection module. 
     In this regard, the contact element is of two-part design, with a first portion of the contact element comprising the insulation displacement contact and the second portion comprising the tuning fork contact, a respective contact limb being arranged on the two portions of the contact element, with the two contact limbs forming an isolating contact in the assembled state. As a result, the isolating contact is integrated into the plug connector. This simplifies the assembly operation for a distributor connection module considerably, since only the assembled plug connector needs to be pushed onto the printed circuit board. Separate assembly of the isolating contacts is not necessary, since they are formed automatically when the plug connector is assembled. In addition, the plug connector can be fitted with cable wires even before it is pushed onto the printed circuit board, since the insulation displacement contacts are supported in the housing and can thus absorb the connection forces. 
     In this case, the isolating contact is preferably in a form such that it can be accessed from the same end as the insulation displacement contacts. For this purpose, the contact limb on the first portion of the lower edge of the insulation displacement contact is bent upward in the direction of the insulation displacement contact, whereas the contact limb of the second portion runs in the opposite direction to the tuning fork contact. 
     In one preferred embodiment, the contact limbs are in a form such that they form a contact region and an insertion region, with the insertion of an isolating connector into the insertion region moving the contact limbs in the contact region away from one another, the isolating connector not touching the contact region. This ensures that wear on the usually plastic isolating connector does not soil the contact region, which would reduce the contact quality. 
     In another preferred embodiment, the inner sides of the chamber-like region have ribs arranged on them which define guides for the tuning fork contacts, the contact regions of the tuning fork contacts protruding beyond the ribs. In this arrangement, the tuning fork contacts are fully accommodated in the longitudinal direction by the plastic housing. As a result, all tuning fork contacts are oriented in a defined manner with respect to one another and can be pushed onto the printed circuit board more easily, since there is no possibility of the tuning fork contacts canting. 
     In another preferred embodiment, the ribs are beveled in the front region, which simplifies the plugging operation. 
     In another preferred embodiment, the insulation displacement contact and the tuning fork contact are arranged so as to be twisted with respect to one another in the region of 45° with respect to one another. 
     In another preferred embodiment, the plastic housing is of two-part design, with the housing portions being able to be latched to one another. One advantage of the two-part housing is the ease of disassembly, which means that plastic and metal parts can very easily be removed for recycling purposes. Assembly is a very simple matter involving the first housing portion being fitted with the first portion of the contact element, and the second housing portion being fitted with the second portion of the contact element, and the two housing portions then being latched to one another. 
     In another preferred embodiment, the plug connector is produced with wire routing eyes. 
     In another preferred embodiment, the outer side of the plug connector has latch elements arranged on it which can be used to latch the plug connector to a further housing which accommodates a printed circuit board. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is explained in more detail below with reference to a preferred exemplary embodiment. In the figures: 
         FIG. 1  shows a perspective exploded view of a plug connector for printed circuit boards, 
         FIG. 2   a  shows a cross section through the assembled plug connector, the section being taken between two clamping bars, 
         FIG. 2   b  shows a cross section along the sectional line P-P, 
         FIG. 3  shows a perspective rear view of the plug connector, 
         FIG. 4  shows a perspective exploded view of a distributor connection module, and 
         FIG. 5  shows a perspective illustration of the assembled distributor connection module. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a perspective view of the plug connector  1 . The plug connector  1  comprises a first housing portion  10 , a second housing portion  20  and a multiplicity of contact elements  30 . The contact element  30  respectively comprises a first portion  30   a  and a second portion  30   b . The first housing portion  10  is produced with clamping bars  11 , wire routing eyes  12  and latching lugs  13 . The second housing portion  20  is produced with latching receptacles  21  and latching lugs  22 . In addition, that portion of the second housing portion  20  which faces the printed circuit board forms a chamber-like region whose inner sides have ribs  23  arranged on them at the top and bottom, which can be seen in part in  FIG. 3 , with the ribs  23  being beveled in the front region. The bevel allows the plug connector to be pushed onto the printed circuit board  70  more easily (see  FIG. 4 ). The contact elements  30  respectively have an insulation displacement contact  31  and a tuning fork contact  32 , with the insulation displacement contact  31  and the tuning fork contact  32  being twisted through approximately 45° with respect to one another. In this arrangement, the insulation displacement contact  31  is associated with the first portion  30   a  of the contact element  30 , and the tuning fork contact  32  is associated with the second portion  30   b  of the contact element  30 . The tuning fork contact respectively has two rounded, inwardly curved contact regions  33 . The insulation displacement contacts  31  on the contact elements  30  are plugged into receptacles between the clamping bars  11 , the latter being mechanically fixed. Arranged on the insulation displacement contact  31  is a first contact limb  34 , which extends from the lower edge  40  of the insulation displacement contact  31  in an upward curve in the direction of the insulation displacement contact  31 . Similarly, a second contact limb  35  extends from the lower edge  42  of the tuning fork contact  32 , but this second contact limb runs in the opposite direction. The two contact limbs  34 ,  35  together form an isolating contact  36 , which is shown in  FIG. 2   a . For the purposes of assembly, the tuning fork contacts  32  are pushed into the second housing portion  20 . In addition, the insulation displacement contacts  31  are pushed into the first housing portion  10 , with the contact limb  34  entering a second lateral cavity in the first housing portion  10  in the process. Next, the second housing portion  20  is latched onto the first housing portion  10 , with the latching lugs  13  engaging in the latching receptacles  21 . In this case, the contact limb  35  likewise enters the cavity and forms the isolating contact  36  together with the contact limb  34 . 
     This assembled state is shown in  FIGS. 2   a, b  and  3 . In this case,  FIG. 2   a  shows a cross section through the plug connector  1 , the interface being situated between two clamping bars. In this arrangement, the two contact limbs  34 ,  35 , which are in resilient contact with one another, form an isolating contact  36 . This isolating contact  36  has an insertion region  37  and a contact region  38 . In this case, it can be seen that the two contact limbs  34 ,  35  touch in the contact region  38  and form an electrical contact. As a result, the insulation displacement contact  31  is electrically connected to its associated tuning fork contact  32 . The first housing portion  10  has an insertion opening  14  for a plug connector (not shown) which can be inserted into the insertion region  37  of the isolating contact  36 . This bends the two contact limbs  34 ,  35  apart and breaks the electrical contact between the insulation displacement contact  31  and the tuning fork contact  32 . In this arrangement, the isolating connector is of such a length that it does not touch the contact limbs  34 ,  35  in the contact region  38 . This prevents wear on the isolating connector from impairing the contact in the contact region  38 . Situated between the two lower regions of the insulation displacement contact  31  and of the tuning fork contact  32  is a slotted clamping bar on which the lower edge  40  of the insulation displacement contact  31  is supported, the tuning fork contact  32  being situated in the slot ( FIG. 2   b ). As can be seen, the tuning fork contact  32  rests on the second housing portion  20  and is clamped from above by the first housing portion  10  ( FIG. 2   a ). Between the lower edge  40  of the insulation displacement contact  31  and the tuning fork contact  32  is an air gap  41 , so that the electrical contact between the two is made exclusively via the contact region  38 . 
       FIG. 4  shows a perspective view of a distributor connection module  80  for telecommunications and data technology with the inventive plug connector  1 . The distributor connection module  80  likewise comprises a first housing portion  50  and a second housing portion  60  which can be latched to one another. The distributor connection module  80  contains a printed circuit board  70 . The second housing portion  60  is produced with two semicircular clamping elements  61  which can be used to latch the distributor connection module  80  onto rods (not shown). For the purpose of passing through a ground connection, the clamping elements  61  are slotted, so that an annular ground contact, which is arranged on the printed circuit board  70 , projects through the slots  62  and makes electrical contact with the metal rods. The first housing portion  50  comprises clamping bars  51  and latching lugs  52  which engage in latching receptacles in the second housing portion  60 . In this arrangement, the clamping bars  51  are of different width, which means that the crosstalk between contact pairs is reduced. Arranged between the clamping bars  51  are contact elements (likewise not shown) which are in the form of insulation displacement contacts in the region of the clampings bars  51  and in the form of tuning fork contacts toward the printed circuit board  70 . Normally, these contact elements are identical to the contact elements  30  in this case. If, by contrast, no isolating contact is required, then the insulation displacement contacts and the tuning fork contact may be of integral design. In principle, the housing portion  50  may be similar to the plug connector  1  in this case. On the side walls, the second housing portion  60  has ventilation slots  63  produced in it, in order to dissipate the heat lost from the components on the printed circuit board  70 . 
     Finally,  FIG. 5  shows the entire distributor connection module  80  with the plug connector  1  latched in. 
     LIST OF REFERENCE NUMERALS 
     
         
           1  Plug connector 
           10  Housing portion 
           11  Clamping bars 
           12  Wire routing eyes 
           13  Latching lugs 
           14  Insertion opening 
           20  Housing portion 
           21  Latching receptacles 
           22  Latching lugs 
           23  Ribs 
           30  Contact elements 
           31  Insulation displacement contact 
           32  Tuning fork contact 
           33  Contact regions 
           34  Contact limb 
           35  Contact limb 
           36  Isolating contact 
           37  Insertion region 
           38  Contact region 
           39  Clamping bar 
           40  Lower edge 
           41  Air gap 
           42  Lower edge 
           50  Housing portion 
           51  Clamping bars 
           52  Latching lugs 
           60  Housing portion 
           61  Clamping elements 
           62  Slots 
           63  Ventilation slots 
           70  Printed circuit board 
           80  Distributor connection module