Patent Publication Number: US-7722404-B2

Title: Plug-in connector for printed circuit boards

Description:
DE 199 45 412 A1 and DE 102 57 308 B3 respectively disclose a plug-in connector for printed circuit boards, comprising a number of contact elements, the contact elements respectively having two connection sides, the one connection side being formed as an insulation-piercing contact for the connecting of wires and the other connection side being formed as a bifurcated contact for the contacting of terminal areas on a printed circuit board, and a plastic housing, in which the insulation-piercing contacts and the bifurcated contact are arranged such that they are turned in relation to each other and at least one lower edge of the insulation-piercing contact is supported on the plastic housing, so that the contact elements are captively held in the plastic housing when connecting forces occur on the insulation-piercing contacts. The plastic housing is in each case formed in two parts, the contact elements first being pushed into the first part of the housing and then the second part of the housing being latched onto the first part of the housing. A disadvantage of the known plug-in connectors for printed circuit boards is that they are relatively complex to produce. 
   The invention is therefore based on the technical problem of providing a plug-in connector for printed circuit boards which is simpler to produce. 
   For this purpose, the plastic housing is formed in one piece, the part receiving the bifurcated contacts being formed at least partly in a resilient manner. This achieves the effect that, when the plastic housing is fitted with the contact elements, it can be bent apart in order to introduce the contact elements and subsequently moves back again resiliently, whereby the contact elements are fixed. The one-part form of the plastic housing has the effect of simplifying the production of the plug-in connector, since now only one injection mold is required. Furthermore, no further plastic housing has to be fitted. 
   In a preferred embodiment, in the transitional region between the insulation-piercing contact and the bifurcated contact, the contact element is formed with two latching elements, which latch into latching receptacles of the plastic housing. The latching receptacles are furthermore preferably formed in this case as apertures in the respective housing wall. 
   In a further preferred embodiment, the bifurcated contacts are completely accommodated by the housing in the longitudinal direction. In this case furthermore grooves or guides in which at least the bifurcated contacts are guided are preferably formed in the inner sides of the housing walls. The actual contact regions of the bifurcated contacts in this case protrude beyond the grooves or guides. 
   In a further preferred embodiment, the plastic housing is formed such that it is at least partly slit at the side walls. On the one hand, this brings about the desired resilience. On the other hand, the slit form allows the plug-in connector also to be fitted onto wider printed circuit boards. 
   In a further preferred embodiment, the insulation-piercing contact and the bifurcated contact are arranged such that they are turned in relation to each other in the range of 45°. The arrangement of the contact elements of an insulation-piercing contact at an angle of about 45° is of advantage with regard to the connecting operation, an edge which can be used for support inevitably forming furthermore when the contact element is formed in one piece as a punched or bent part. 
   In a further preferred embodiment, the insulation-piercing contact and the bifurcated contact lie on a common center axis. The advantage of this embodiment is that the connecting forces occurring on the insulation-piercing contact bring about no bending moments, or insignificant bending moments, on the bifurcated contact. Furthermore, the plug-in connector can be made narrower with the same number of contact elements. 
   In a further preferred embodiment, the plug-in connector is latched on a front frame by means of a latching spring, it being possible for the plug-in connector to be released from the front side of the front panel by means of the latching spring. One possible configuration of such a latching spring is described in DE 101 41 449 A1 for use in the case of an adapter for optical-fiber plug-in connectors, reference hereby being made expressly to the statements made with respect to the latching spring. 

   
     The invention is explained in more detail below on the basis of a preferred exemplary embodiment. In the figures: 
       FIG. 1  shows a side view of a plug-in connector, 
       FIG. 2  shows a plan view of the plug-in connector, 
       FIG. 3  shows a sectional representation through the plug-in connector and 
       FIG. 4  shows a perspective representation of the plug-in connector with a pulled-out contact element. 
   

   In  FIG. 1 , the plug-in connector  1  is represented in a side view. The plug-in connector  1  comprises a one-part plastic housing  2 . In the upper region, the plastic housing  2  is formed with clamping ribs  3 , between which insulation-piercing contacts  11  of contact elements  10  are arranged (see  FIG. 4 ). Arranged underneath the clamping ribs  3  on a wall of the housing is a wire guide  5 . In the lower region of the plastic housing  2 , where the bifurcated contacts  12  of the contact elements  10  lie, the housing has latching receptacles  6 , which are formed as rectangular apertures. Between respective pairs of latching receptacles  6 , the housing wall  4  has groove-shaped depressions  7 . Furthermore, the housing wall  4  has at the sides two receptacles  8  for a locking mechanism (not represented), by means of which the plug-in connector  1  can be fastened for example to a metallic front frame. On the inner side, the housing wall  4  is formed with grooves  9 , in which the bifurcated contacts  12  are guided with their side surfaces  13 . The actual contact regions  14  of the bifurcated contacts  12  are in this case curved inward and protrude out of the groove  9 . In the transitional region between the bifurcated contact  12  and the insulation-piercing contact  11 , the contact element  10  has two detents  15 , which, as can be seen in  FIG. 3  or  4 , are latched in the latching receptacles  6 . It can also be seen in  FIG. 3  that the insulation-piercing contact  11  and the bifurcated contact  12  lie on a common center axis  16 . Furthermore, it can be seen in  FIG. 3  how the detents  15  are supported in the downward direction on bearing surfaces  20  in the plastic housing  2 . These bearing surfaces  20  absorb the connecting forces occurring during the wiring of the insulation-piercing contacts  11 . Furthermore, the plastic housing has stop surfaces  21  and  22 , which the contact element  10  comes up against with its edges  17  and  18 . The side walls  23  of the plastic housing  2  also respectively have a slot  24  in the region of the bifurcated contacts  12 . On account of the slot  24 , the two housing walls  4  can be bent open resiliently with respect to each other, so that the contact elements  10  can be pushed with the detents  15  from below into the plastic housing  2 , until the detents  15  latch in the latching receptacles  6 . 
   LIST OF DESIGNATIONS 
   
       
         1  plug-in connector 
         2  plastic housing 
         3  clamping rib 
         4  housing wall 
         5  wire guide 
         6  latching receptacles 
         7  depression 
         8  receptacle 
         9  groove 
         10  contact element 
         11  insulation-piercing contact 
         12  bifurcated contact 
         13  side surface 
         14  contact region 
         15  detent 
         16  center axis 
         17  edge 
         18  edge 
         20  bearing surface 
         21  stop surface 
         22  stop surface 
         23  side wall 
         24  slot