Patent Publication Number: US-7722403-B2

Title: Grounding comb, in particular for a plug-type connector for printed circuit boards

Description:
BACKGROUND OF THE INVENTION 
   The invention relates to a grounding comb, in particular for a plug-type connector for printed circuit boards. 
   DE 10 2004 017 605 B3 has disclosed a plug-type connector for printed circuit boards, comprising a number of contact elements, the contact elements each having two connection sides, one connection side being in the form of an insulation displacement contact for connecting wires, and the other connection side being in the form of a fork contact for making contact with connection pads on a printed circuit board, and a plastic housing, into which the insulation displacement contacts of the contact elements can be inserted, at least one lower edge of the insulation displacement contact being supported on the plastic housing, with the result that the contact elements are held in the plastic housing such that they cannot fall out in the event of connection forces occurring on the insulation displacement contacts, the plastic housing comprising at least one chamber-shaped region, and the fork contacts being accommodated completely in the longitudinal direction of the plastic housing, the contact element having two parts, the first part comprising the insulation displacement contact, and the second part comprising the fork contact, in each case one contact limb being arranged on both parts and the two contact limbs forming an isolation contact, the plastic housing having two pieces, the first housing part accommodating the insulation displacement contact, and the second housing part accommodating the fork contact, and both housing parts being latched to one another, the insulation displacement contact being supported on a slit clamping web of the second housing part, said fork contact lying in the slit of the clamping web, being supported in the interior of the second housing part and being clamped in by the first housing part. In this case, the isolation contact represents an interface via which, in addition to isolating plugs, surge protection plugs or magazines can also be connected. 
   SUMMARY OF THE INVENTION 
   The invention is based on the technical problem of providing a grounding comb, in particular for a plug-type connector for printed circuit boards which allows for improved integration of surge arresters. 
   The grounding comb, in particular for a plug-type connector for printed circuit boards, comprises a carrier, which extends in the longitudinal direction and on which laterally sprung contact lugs are arranged, the contact lugs lying exactly opposite one another on the two longitudinal sides. 
   In a preferred embodiment, at least one grounding contact is arranged on at least one front side of the carrier, the grounding contact preferably being in the form of a fork contact or ring contact and further preferably being in the form of a double contact. 
   In a further preferred embodiment, the sprung contact lugs are in the form of a cross. 
   In a further preferred embodiment, the contact lugs are bent back outwards at the free ends. 
   In a further preferred embodiment, the grounding contact extends in the same direction as the contact lugs. 
   In a further preferred embodiment, the carrier is curved. 
   In a further preferred embodiment, the grounding comb is formed in one piece. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be explained in more detail below with reference to a preferred exemplary embodiment. In the figures: 
       FIG. 1  shows a perspective front view of a plug-type connector for printed circuit boards; 
       FIG. 2  shows a front view of the plug-type connector, 
       FIG. 3  shows a plan view of the plug-type connector, 
       FIG. 4  shows a perspective view from below of the plug-type connector, 
       FIG. 5  shows a perspective view from below without the housing part, 
       FIGS. 6   a - c  show various perspective illustrations of a contact element, 
       FIG. 7   a  shows a front view of a grounding comb, 
       FIG. 7   b  shows a plan view of the grounding comb, 
       FIG. 7   c  shows a side view of the grounding comb, 
       FIG. 8  shows a cross section of the plug-type connector along the section line B-B shown in  FIG. 2 , and 
       FIG. 9  shows a perspective front view of the plug-type connector with the positioning tool placed thereon. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
   The plug-type connector  1  for printed circuit boards comprises a first housing part  2  and a second housing part  3 , which are preferably connected to one another by a latching connection. The first housing part  2  has raised webs  4 , between which insulation displacement contacts  11  of contact elements  10  (see  FIGS. 6   a - c ) are guided. The webs  4  are arranged in a row which extends in the longitudinal direction L. In this case, webs  4  are arranged laterally offset with respect to the center line, the other side being positioned deeper. On this side of the upper side  5 , the first housing part  2  has openings, into which a grounding comb  6  is inserted (see  FIGS. 7   a - c ). The second housing part  3  is formed with guides  7 , in which the fork contacts  12  of the contact elements  10  are guided, preferably the guides  7  completely accommodating the fork contacts  12 , i.e. said fork contacts not protruding beyond the underside  8  of the second housing part  3 . 
   Before the construction of the plug-type connector  1  is explained in more detail, the construction of the contact element  10  should first be explained in more detail with reference to  FIGS. 6   a - c  and that of the grounding comb  6  with reference to  FIGS. 7   a - c.    
   The one-piece contact element  10  comprises an insulation displacement contact  11 , a fork contact  12  and a contact face  13 . In this case, the insulation displacement contact  11  and the fork contact  12  are aligned in opposite directions to one another, i.e. the insulation displacement contact  11  is accessible from the upper side  5  of the first housing part  2  and the fork contact  12  is accessible from the underside  8  of the second housing part  3 . In this case, the plane E 1  of the insulation displacement contact  11  is at an angle of 45° with respect to the plane E 2  of the fork contact  12 . A web-shaped extension  14  protrudes from the fork contact  12 , this web-shaped extension then being adjoined by the contact face  13  via a web  28 . The web  28  and the contact face  13  in this case form a T-shaped contact. In this case, the plane E 3  of the contact face  13  is at a right angle with respect to the plane E 2  of the fork contact  12 . The width of the contact face  13  in this case ensures that the contact face  13  makes reliable contact with a two-pole surge arrester. 
   The grounding comb  6  comprises a carrier  15 , which extends in the longitudinal direction L and on which laterally sprung contact lugs  16  are arranged. In this case, the contact lugs  16  are precisely opposite one another on the two longitudinal sides of the carrier  15 . The sprung contact lugs  16  have a cruciform shape, with the result that, owing to the tapering towards the carrier  15 , a sufficient spring effect is ensured. At the lower end, the contact lugs  16  are bent slightly outwards in order to therefore facilitate the plug-in operation into the first housing part  2 . 
   A double fork contact  18 , which extends in the same direction as the contact lugs  16 , is arranged on a front side  17  of the carrier  15 . The double fork contact  18  has the advantage that, in comparison with a single fork contact, more current is transmitted. There is also simpler fitting when latching-on the plug-type connector. 
     FIG. 5  illustrates the plug-type connector  1  in a view from below without the second housing part  3 . In the interior, the first housing part  2  is formed with receptacles  20 ,  21  and  27 . In this case, the first housing part  2  comprises ten receptacles  20 , ten receptacles  21  and twenty receptacles  27 , the receptacles  20  and  21  each being arranged in a row extending in the longitudinal direction L. In this case, in each case one receptacle  20  and one receptacle  21  are associated with one another as a pair and are separated from one another by a wall  22 , the two receptacles associated with one another as a pair extending in the form of a receptacle pair  20 ,  21  in the transverse direction Q. The receptacle pairs  20  and  21  of a row are separated from one another in the longitudinal direction L by a wall  23 . Two-pole surge arresters  24  are arranged in the receptacles  20  and  21 , which surge arresters essentially have a cylindrical shape. The two-pole surge arresters  24  are each formed on the base and lid with a contact (pole)  25  in the form of a circular ring, contact then being made with said surge arresters by the contact face  13  and the contact lugs  16  from both pole sides. For this purpose, the contact face  13  of a contact element  10  and a contact lug  16  of the grounding comb  6  in each case protrude into a receptacle  20 ,  21 , the two contact faces  13  bearing, in the receptacles  20 ,  21 , in each case on both sides against the wall  22  (see also  FIG. 8 ). In this case, the contact faces  13  are relatively rigid. The contact elements  10  for the receptacles  20  and  21  also have different shapes. In the inserted state, the insulation displacement contacts  11  of all the contact elements  10  are aligned parallel to one another. The same applies to the fork contacts  12 . However, the extension  14  of the contact elements  10  for the receptacles  21  is longer than that of the contact elements  10  for the receptacles  20 . Furthermore, the bent-back portion of the contact face  13  is turned around. On the basis of the illustration in  FIG. 5 , the contact face  13  of the contact element  10  for the receptacle  20  is bent back from the extension  14  by 90° towards the right, whereas the contact face  13  of the contact element  10  with the longer extension for the receptacle  21  is bent back from the extension  14  through 90° towards the left. 
   In addition, twenty receptacles  27  for accommodating the insulation displacement contacts  11  are provided which likewise extend in the longitudinal direction L. In this case, in each case two receptacles  27  are associated with one receptacle pair  20 ,  21 , aligned in the transverse direction Q. 
     FIG. 5  shows, in the left-hand region, a housing part  2  which has been completely fitted with contact elements  10 . In the right-hand region, six contact elements  10  have been removed in the first three receptacle pairs  20 ,  21  in order to make the receptacles  20 ,  21  and  27  more visible. Furthermore, for this purpose the first receptacle pair  20 ,  21  is illustrated in the right-hand region of the housing part  2  and the receptacle  21  without the surge arresters  24  is illustrated in the second receptacle pair  20 ,  21  from the right. In the case of two receptacle pairs,  20 ,  21 , in order to better illustrate the different lengths of the extensions  14  and the different bends in the webs  28  for the contact faces  13 , in each case one contact element  10  with a longer and shorter extension  14  has been removed. 
   The two-pole surge arresters  24  are in this case aligned in the receptacles  20 ,  21  in such a way that the base and lid faces are aligned parallel to the side face  26  of the first housing part  2 . In this case, note should be made of the fact that the receptacles  20  and  21  of a pair do not necessarily need to be aligned, but embodiments are also possible where these are offset with respect to one another. 
   Finally,  FIG. 9  illustrates the plug-type connector  1  with a positioning tool  30  for wires  32  for making contact with the insulation displacement contacts  11 . The webs  4  for the insulation displacement contacts  11  are raised with respect to the grounding comb  6  in such a way that the lifting operation of the positioning tool  30  is not impeded and sufficient space can be made available for the run of a cable  31  of the wires  32  with which contact has been made above the grounding comb  6 . 
   LIST OF REFERENCE SYMBOLS 
   
       
         1  Plug-type connector 
         2  First housing part 
         3  Second housing part 
         4  Webs 
         5  Upper side 
         6  Grounding comb 
         7  Guides 
         8  Underside 
         10  Contact elements 
         11  Insulation displacement contact 
         12  Fork contact 
         13  Contact face 
         14  Extension 
         15  Carrier 
         16  Contact lugs 
         17  Front side 
         18  Double fork contact 
         20  Receptacles 
         21  Receptacles 
         22  Wall 
         23  Wall 
         24  Surge arresters 
         25  Contact 
         26  Side face 
         27  Receptacles 
         28  Web 
         30  Positioning tool 
         31  Cables 
         32  Wires 
       E 1  Plane 
       E 2  Plane 
       E 3  Plane 
       L Longitudinal direction 
       Q Transverse direction