Patent Publication Number: US-6663426-B2

Title: Floating interface for electrical connector

Description:
BACKGROUND OF THE INVENTION 
     Certain embodiments of the present invention generally relate to improvements in electrical connectors that connect printed circuit boards to one another and more particularly relate to electrical connectors that include floating interfaces to ensure proper contact between components of the connectors. 
     Various electronic systems, such as computers, comprise a wide array of components mounted on printed circuit boards, such as daughterboards and motherboards, which are interconnected to transfer signals and power throughout the systems. The transfer of signals and power between the circuit boards requires electrical connectors between the circuit boards. Typical connector assemblies include a plug connector and a receptacle connector. Each plug and receptacle connector may house a plurality of electrical wafers. An electrical wafer may be a thin printed circuit board or a series of laminated contacts within a plastic carrier. The electrical wafers within one connector may communicate with the electrical wafers in the other connector through a backplane. Alternatively, the electrical wafers may edge mate in an orthogonal manner obviating the need for a backplane. 
     Electrical wafers, however, may be misaligned within the connectors that house the wafers. The misalignment may be caused by manufacturing processes used to manufacture the wafers and/or connectors. The misalignment between two wafers that mate with one another may cause a poor connection, and thus a poor signal path, between the wafers. For example, forming mounting channels, into which the electrical wafers are received, in one connector may produce a possible misalignment with a counterpart wafer in the other connector. That is, one connector may have channels with a first tolerance, while the other connector may have channels having a similar or different tolerance. Added together, the tolerances may provide a wide range of motion over which the wafers may move. If the wafers move too much over the range of motion, a poor electrical connection may result between mating wafers. That is, if two wafers mate with each other at an angle that provides poor contact between the wafers, the electrical connection between the two wafers may be less than desired, or non-existent. Additionally, over time, connectors may warp due to stresses and strains within the systems in which they are utilized. When a wafer is misaligned with a counterpart wafer to which it is supposed to mate, signals between the wafers may be attenuated, diminished, or even completely blocked. Also, misalignment may occur within a connector system using conventional contacts. 
     Thus a need has existed for an electrical connector that maintains proper contact between wafers and/or contacts included within a first connector and those in a second connector. Specifically, a need has existed for an electrical connector that maintains proper alignment, and corrects misalignments, between circuit boards, or wafers, within a first connector and those of a second connector housing. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with an embodiment of the present invention, a connector assembly has been developed that includes a first connector mated with a second connector. Each connector includes a housing and at least one conductive wafer configured to engage electrical contacts. The housing includes a base having a rear end and an interface end. The base also includes at least one channel extending between the rear and interface ends. Each conductive wafer is divided into a rear portion and an interface portion. The rear portion is received and securely retained in a channel with the interface portion extending beyond the interface end of the base. The interface portion includes a contact edge. The interface portion moves in a direction that is transverse to a plane of the conductive wafer in order to facilitate alignment with a mating structure, such as another conductive wafer. 
     Certain embodiments of the present invention may also include flex limiting wedges positioned on either side of a channel at the interface end. The flex limiting wedges define a range of motion over which the interface portion moves. 
     Certain embodiments of the present invention may also include an interface housing, which receives and securely retains the interface portion of the conductive wafer. The interface housing moves in the same direction as the interface portion of the conductive wafer. 
    
    
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is an isometric view of an interior of a receptacle connector formed in accordance with an embodiment of the present invention. 
     FIG. 2 is an isometric view of an interior of a plug connector formed in accordance with an embodiment of the present invention. 
     FIG. 3 is an isometric view of a ground terminal formed in accordance with an embodiment of the present invention. 
     FIG. 4 is an isometric view of a signal terminal formed in accordance with an embodiment of the present invention. 
     FIG. 5 is an isometric interior view of a receptacle wafer orthogonally mated with a plug wafer according to an embodiment of the present invention. 
     FIG. 6 is an isometric view of a receptacle connector formed in accordance with an embodiment of the present invention. 
     FIG. 7 is an isometric view of a plug connector formed in accordance with an embodiment of the present invention. 
     FIG. 8 illustrates a top view of a receptacle wafer mated with a plug wafer according to an embodiment of the present invention. 
     FIG. 9 illustrates a side view of a receptacle wafer mated with a plug wafer according to an embodiment of the present invention. 
     FIG. 10 is an isometric view of a receptacle connector mated in a coplanar fashion with a plug connector, according to an embodiment of the present invention. 
     FIG. 11 is an isometric view of a plug connector according to an embodiment of the present invention. 
     FIG. 12 is an isometric view of an interior of a plug connector according to an embodiment of the present invention. 
     FIG. 13 is a side view illustrating movement of signal and ground terminals during an upward shift of a receptacle wafer, according to an embodiment of the present invention. 
     FIG. 14 is an isometric view of a latching system formed in accordance with an embodiment of the present invention. 
     The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, certain embodiments. It should be understood, however, that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is an isometric view of an interior of a receptacle connector  100  formed in accordance with an embodiment of the present invention. The receptacle connector  100  includes a base  120  and receptacle circuit boards, or wafers  110  (although only one receptacle wafer  110  is shown in FIG. 1) having a rear portion  113 , a flex portion  112  and an interface portion  117 . The base  120  includes an interface side  118 , side walls  116  and a rear wall  108 . The rear wall  108  includes cover mating notches  122  having latch mating members  123  that receive and retain cover latches (not shown) formed on a cover (not shown). Latch members  130  extend outwardly from the bottom of the base  120  at the interface side  118 . The latch members  130  may be integrally formed with the base  120 , or they may be separate structures mounted on the base  120 . The base  120  also includes channels  128  extending along a length thereof. Each channel  128  includes a series of receptacles  126 . Each receptacle  126  retains a compliant contact  106 . Each compliant contact  106  includes a single prong that extends down through the bottom of the base  120 , and a double prong (not shown) that extends up through the top of the base  120 . Each channel  128  is closed by the rear wall  108  and open at the interface side  118 . At the interface side  118 , each channel  128  is positioned between flex limiting wedges  124 . The flex limiting wedges  124  are formed such that a wide end  125  distal to the interface side  118  is wider than a tapered end  127  proximal to the interface side  118 . Alternatively, the flex limiting wedges  124  may be included within an interior of a floating interface housing  620  (shown with respect to FIG.  6 ), instead of within the base  120 . 
     Each channel  128  receives and retains a receptacle circuit board, or wafer  110 . Each receptacle wafer  110  includes a base mating edge (hidden by insertion of the receptacle wafer  110  into the channel  128 ) and plug mating edge  111 . The base mating edge has signal and contact pads (not shown), and the plug mating edge  111  also has signal contact pads  190 , and ground contact pads (on opposite side of receptacle wafer  110 ). As shown in FIG. 1, the plug mating edge  111  is located at the edge of the interface portion  117 . Signal and ground terminals, or contact members,  22  and  12 , respectively, (as shown with respect to FIGS. 3 and 4) connect to contact pads on the plug mating edge  111 . That is, signal terminals  22  contact signal contact pads  190 , while ground terminals  12  contact ground contact pads. The contact pads (not shown) of the base mating edge are positioned between double prongs (not shown) of compliant contacts  106 . That is, the double prongs straddle the receptacle wafer  110  and contact it at contact pads located on the base mating edge. The compliant contacts  106  in turn connect to a printed circuit board  102  through receptacles (not shown) formed in the printed circuit board  102  that receive and retain single prongs (not shown) of the compliant contacts  106 . Thus, an electrical path may be established between the printed circuit board  102  and the receptacle wafer  110 . 
     A rear portion  113  of a receptacle wafer  110  is securely retained in a channel  128 . The receptacle wafer  110  is securely retained from the rear portion  113  to the flex portion  112 . Flex holes  114  are formed in each receptacle wafer  110 . The flex holes  114  are formed in one or more columns extending in a direction transverse to a length of the channels  128 . The area between the columns of flex holes  114  is approximately the length of the flex limiting wedge  124 , such that one column of flex holes  114  is proximate to the wide end  125  of a flex limiting wedge  124 , while the other column of flex holes  114  is proximate to a tapered end  127  of the flex limiting wedge  124 . While the receptacle wafer  110  may be covered with a solder mask, the solder mask may be removed at the flex portion  112  to provide added flexibility in the flex portion  112 . Additionally, the flex holes  114  provide a weakened area in the receptacle wafer  100  such that the area between the flex holes  114 , that is the flex portion  112 , may flex easier than the rear portion  113  or the interface portion  117  of the receptacle wafer  110 . Also, copper in the flex portion  112  may be removed to provide further weakening of the flex portion  112 . 
     The flexion of each flex portion  112  is limited by the flex limiting wedges  124 , which are positioned on either side of the receptacle wafer  110 . As mentioned above, the flex limiting wedges  124  may be included within the base  120  or the interior of the floating interface housing  620 . Because the tapered end  127  of each flex limiting wedge  124  is thinner than the wide end  125 , the receptacle wafer  110  may flex between the tapered ends  127  of two flex limiting wedges  124  that are positioned on either side of the receptacle wafer  110 . Line A denotes the directions in which the flex portions  112  may flex, and the interface portions  117  may move. That is, the flex portions  112  of the receptacle wafers  110  may flex horizontally (as shown in FIG.  1 ), or in a direction perpendicular to the plane of the receptacle wafers  110 . The flexion of the flex portions  112  is limited by the flex limiting wedges  124 . Thus, the movement of the interface portions  117  is limited by the flex limiting wedges  124 . Each tapered end  127  acts as a physical barrier beyond which a flex portion  112  of a receptacle wafer  110  cannot flex. The portion of the flex portion  112  proximate the tapered ends  127  of two flex limiting wedges  124  may flex over a greater range of motion as compared to the portion of the flex portion  112  proximate the corresponding wide ends  125 . While the flex portion  112  of a receptacle wafer  100  may flex, the rear portion  113  and the interface portion  117  of the receptacle wafer  110  remain rigid and straight, relative to the flexion of the flex portion  112 . That is, the rear portion  113  is securely retained by the channel  128 , while the interface portion  117  is securely retained in interface slots of a floating interface housing  620 , as shown with respect to FIG.  6 . However, the interface portion  117  moves out of the plane of the rear portion  113  in response to the flexion of the flex portion  112 . That is, while the interface portion  117  may move, it remains relatively straight and rigid, as compared to the flex portion  112 . 
     FIG. 2 is an isometric view of an interior of a plug connector  200  formed in accordance with an embodiment of the present invention. The plug connector  200  includes a base  220  and plug circuit boards, or wafers  210  (although only one plug wafer  210  is shown in FIG. 2) having a rear portion  213 , a flex portion  212  and an interface portion  217 . The base  220  includes an interface side  218 , side walls  216  and a rear wall  208 . The rear wall  208  includes cover mating notches  222  having latch mating members  223  that receive and retain cover latches (not shown) formed on a cover (not shown). Latch members  230  extend outwardly from the bottom of the base  220  at the interface side  218 . The latch members  230  may be integrally formed with the base  220 , or they may be separate structures mounted on the base  220 . The base  220  also includes channels  228  extending along a length thereof. Each channel  228  includes a series of receptacles  226 . Each receptacle  226  retains a compliant contact  206 . Each compliant contact  206  includes a single prong (not shown) that extends down through the bottom of the base  220 , and a double prong (not shown) that extends up through the top of the base  220 . Each channel  228  is closed by the rear wall  208  and open at the interface side  218 . At the interface side  218 , each channel  228  is positioned between flex limiting wedges  224 . The flex limiting wedges  224  are formed such that a wide end  225  distal to the interface side  218  is wider than a tapered end  227  proximal to the interface side  218 . Alternatively, the flex limiting wedges  224  may be included within an interior of a floating interface housing  720  (shown with respect to FIG.  7 ), instead of within the base  220 . 
     Each channel  228  receives and retains a plug circuit board, or wafer  210 . Each plug wafer  210  includes a base mating edge (hidden by insertion of the plug wafer  210  into the channel  128 ) and plug mating edge  211 . The base mating edge has signal and contact pads (not shown), while the plug mating edge  211  has signal contact pads  290  and ground contact pads  292 . As shown in FIG. 2, the plug mating edge  211  is located at the edge of the interface portion  217 . Signal and ground terminals, or contact members,  22  and  12 , respectively (as shown with respect to FIGS. 3 and 4) connect to contact pads  290  and  292 , respectively, on the plug mating edge  211 . The contact pads of the base mating edge are positioned between double prongs (not shown) of compliant contacts  206 . That is, the double prongs straddle the plug wafer  210  and contact it at contact pads located on the base mating edge. The compliant contacts  206  in turn connect to a printed circuit board  202  through receptacles (not shown) formed in the printed circuit board  202  that receive and retain single prongs (not shown) of the compliant contacts  206 . Thus, an electrical path may be established between the printed circuit board  202  and the plug wafer  210 . 
     A rear portion  213  of a plug wafer  210  is securely retained in a channel  228 . The plug wafer  210  is securely retained from the rear portion  213  to the flex portion  212 . Flex holes  214  are formed in each plug wafer  210 . The flex holes  214  are formed in one or more columns extending in a direction transverse to a length of the channels  128 . The area between the columns of flex holes  214  is approximately the length of the flex limiting wedge  224 , such that one column of flex holes  214  is proximate to the wide end  225  of the flex limiting wedge  224 , while the other column of flex holes  214  is proximate to the tapered end  227  of the flex limiting wedge  224 . While the plug wafer  210  may be covered with a solder mask, the solder mask may be removed at the flex portion  212  to provide added flexibility in the flex portion  212 . Additionally, the flex holes  214  provide a weakened area in the plug wafer  210  such that the area between the flex holes  214 , that is the flex portion  212 , may flex easier than the rear portion  213  or the interface portion  217  of the plug wafer  210 . 
     The flexion of each flex portion  212  is limited by the flex limiting wedges  224 , which are positioned on either side of the plug wafer  210 . Because the tapered end  227  of each flex limiting wedge  224  is thinner than the wide end  225 , the plug wafer  210  may flex between the tapered ends  227  of two flex limiting wedges  224  that are positioned on either side of the plug wafer  210 . Line B denotes the directions in which the flex portions  212  may flex, and the interface portions  217  may move. That is, the flex portions  212  of the plug wafers  210  may flex vertically (as shown in FIG.  1 ), or in a direction perpendicular to the plane of the plug wafers  210 . The flexion of the flex portions  212  is limited by the flex limiting wedges  224 . Each tapered end  227  acts as a physical barrier beyond which the receptacle wafer  210  cannot flex. The portion of the flex portion  212  proximate the tapered ends  227  of two flex limiting wedges  224  may flex over a wider range of motion as compared to the portion of the flex portion  212  proximate the corresponding wide ends  225  due to the tapered nature of the flex limiting wedges  224 . While the flex portion  212  of a plug wafer  210  may flex, the rear portion  213  and the interface portion  217  of the plug wafer  210  remain rigid and fixed. That is, the rear portion  213  is securely retained by the channel  228 , while the interface portion  217  is securely retained in interface slots of a floating interface housing  720 . However, the interface portion  217  moves out of the plane of the rear portion  213  in response to the flexion of the flex portion  212 . That is, while the interface portion  217  may move, it remains relatively straight and rigid, as compared to the flex portion  212 . 
     FIG. 3 is an isometric view of a ground terminal, or ground contact member,  12  formed in accordance with an embodiment of the present invention. The ground terminal  12  includes a single beam receptacle interconnect  14  on one end of an intermediate portion  16  and a plug ground interconnect  18  shaped like a tuning fork on the opposite end. The plug ground interconnect  18  includes two prongs  2  and  4 . Therefore one prong  2  of the plug ground interconnect  18  contacts a ground contact pad  292  on one side of the plug wafer  210  while the other prong  4  of the plug ground interconnect  18  contacts a ground contact pad  292  on the other side of the plug wafer  210 . That is, the plug wafer  210  is straddled by receptacle ground interconnects  18 . The single beam receptacle interconnect  14  contacts a ground contact pad (not shown) located on one side of the receptacle wafer  110 . 
     FIG. 4 is an isometric view of a signal terminal, or signal contact member,  22  formed in accordance with an embodiment of the present invention. The signal terminal  22  includes a double beam receptacle interconnect  24  on one side of an intermediate portion  26  and a plug signal interconnect  28  shaped like a tuning fork on the opposite end. The plug signal interconnect  28  includes two prongs  3  and  5 . Therefore one prong  3  of the plug signal interconnect  28  contacts a signal contact pad  290  on one side of the plug wafer  210  while the other prong of the plug signal interconnect  28  contacts a signal contact pad  290  on the other side of the plug wafer  210 . That is, the plug wafer  210  is straddled by the plug signal interconnect  28 . The double beam receptacle interconnect  24  contacts a signal contact pad  190  located on one side of the receptacle wafer  110 . That is, both beams of the receptacle interconnect  24  contact one signal contact pad  190  located on one side of the receptacle wafer  110 . 
     FIG. 5 is an isometric interior view of a receptacle wafer  110  orthogonally mated with a plug wafer  210  according to an embodiment of the present invention. As shown in FIG. 5, the signal terminal  22 , through the double beam receptacle interconnect  24 , engages a signal contact pad  190  on the receptacle wafer  110  on a first side, while the ground terminal  12 , through the single beam receptacle interconnect  14  engages a ground contact pad (on hidden side of receptacle wafer  110 ) on the same receptacle wafer  110  on a second side. However, the plug signal interconnect  28 , through the prongs  3  and  5 , straddles the plug wafer  210  such that the signal terminal  22  engages signal contact pads  290  on both sides of the plug wafer  210 . Similarly, the plug ground interconnect  18 , through the prongs  2  and  4 , straddles the plug wafer  210  such that the ground terminal  12  engages ground contact pads  292  on both sides of the plug wafer  210 . Thus, the receptacle wafer  110  is positioned between a plurality of signal terminals  22  on one side of the receptacle wafer  110  and a plurality of ground terminals  12  on a second side of the receptacle wafer  110 . A plug wafer  210 , on the other hand, is positioned between a plurality of signal and ground terminals  22  and  12 , each of which contacts the plug wafer  210  on both sides. 
     FIG. 8 illustrates a top view of a receptacle wafer  110  mated with a plug wafer  210  according to an embodiment of the present invention. In FIG. 8, most of the supporting structure, such as the flex limiting wedges  124  and  224 , is not shown. FIG. 8 a  shows a receptacle wafer  110  in a substantially straight alignment. That is, no lateral forces are warping the receptacle wafer  110 , or forcing the flex portion  112  to flex. In FIGS. 8 b  and  8   c , however, lateral forces (F) are exerted on the receptacle wafer  110 . The movement of the signal terminal  22  and ground terminal is exaggerated to better show the movement of the flex portion  112 . As shown in FIGS. 8 b  and  8   c , only the flex portion  112  flexes, while the rear and interface portions  113 ,  117  of the receptacle wafer  110  remain in a straight alignment. However, the interface portion  117  moves (but does not flex) relative to the rear portion  113  in response to the flexion of the flex portion  112 . 
     FIG. 9 illustrates a side view of a receptacle wafer  110  mating with a plug wafer  210  according to an embodiment of the present invention. In FIG. 9, most of the supporting structure, such as the flex limiting wedges  124  and  224 , is not shown. FIG. 9 a  shows a plug wafer  210  in a substantially straight alignment. That is, no upward or downward forces are warping the plug wafer  210 , or forcing the flex portion  212  to flex. As in FIG. 8, the movement in FIG. 9 is exaggerated. In FIGS. 9 b  and  9   c  upward and downward forces are exerted on the plug wafer  210 . The forces cause the signal terminal  22  and the ground terminal  12  (ground terminal  12  hidden in FIG.  9 ), which clip to the plug wafer  110  through prongs  3  and  5 , in the case of the signal terminal  22 , and prongs  2  and  4 , in the case of hidden ground terminal  12 , to move in response to the force. Prongs  3 ,  5  and  2 ,  4  may also flex. For example, the prongs  3 , 5  and  2 ,  4  may flex by an amount depending on the flex of the flex portion  212 . As shown in FIGS. 8 b  and  8   c , only the flex portion  212  flexes, while the rear and interface portions  213 ,  217  of the plug wafer  210  remain in a straight alignment. However, the interface portion  217  moves (but does not flex) relative to the rear portion  213  in response to the flexion of the flex portion  212 . 
     FIG. 6 is an isometric view of a receptacle connector  100 , without receptacle wafers  110 , formed in accordance with an embodiment of the present invention. The receptacle connector includes the base  120 , a floating interface housing  620  and a cover  610 . The floating interface housing  620  has latch recesses  650  having latch projections  652  protruding therefrom and latch flexion limiting lips  660 . The floating interface housing  620  also includes side walls  622 , a top wall  624 , a wafer projection wall  630  and a bottom wall  626 , which define an interface cavity  628 . The latch recesses  650  and latch projections  652  are formed on the exterior of the top wall  624  and the bottom wall  626 . The wafer projection wall  630  includes slots  632  extending from the top wall  624  to the bottom wall  626 . The slots  632  allow the receptacle wafers  110  to pass through. The side of the bottom wall  626  within the interface cavity  628  includes guide slots  640  that receive and securely retain lower edges of the interface portions  117  of the receptacle wafers  110 . Additionally, the side of the top wall  624  facing the interface cavity  628  may also include guide slots that receive and securely retain upper edges of the interface portions  117  of the receptacle wafers  110 . Thus, upon complete assembly of the receptacle connector  100 , each receptacle wafer  110  is fixed in a straight orientation at its rear portion  113  and its interface portion  117 . Only the flex portion  112  of each receptacle wafer  110  flexes, while the rear portion  113  and the interface portion  117  remain relatively rigid and straight as compared to the flex portion  112 . However, as mentioned above, while the interface portion  117  remains in a straight orientation, the interface portion  117  moves in response to the flexing of the flex portion  112 . 
     The cover  610  includes a top wall  612 , side walls  616 , a rear wall  614 , latch members  130  and cover latches  642 . An open cavity (not shown) is defined by the walls  612 ,  616  and  614 . In FIG. 6, the latch mating members  123  and cover mating notches  122  are formed on the side walls  116  of the base  120 . As shown in FIG. 1, however, the latch mating members  123  and cover mating notches  122  may be formed on the rear wall  108  of the base  120 . Alternatively, these features may be located on the side walls  116  and the rear wall  108 . The cover latches  642  are oriented on the cover  610  to correspond to the position(s) of the cover mating notches  122  and the latch mating members  123 . The cover latches  642  are received by the cover mating notches  122  and retained by the latch mating members  123 . Optionally, instead of using a latching system to fasten the cover  610  to the base  120 , the cover  122  may be fastened to the base  120  through screws, glue, and the like. 
     The latch members  130  may be integrally formed with the top wall  612  of the cover  610 , or they may be separately mounted on the top wall  612 . The latch members  130  on the cover  610  and on the base  120  have a flex end  656  and a retained end  654 . The latch members  130  engage the latch recesses  650  and mate with the latch projections  652 . The retained ends  654 , which are retained by the latch recesses  650 , remain fixed while the flex ends  656  may move, relative to the actual movement of the floating interface housing  620 , in the directions denoted by line A. That is, the flex ends  656 , because they are connected or formed integrally with the stationary cover  610  or base  120 , do not actually move. The floating interface housing  620  moves, which produces relative motion between the flex ends  656  and the floating interface housing  620 . The movement of the flex ends  656  is limited by the latch flexion limiting lips  660 , which form a barrier that impedes continued movement of the latch members  130 . 
     FIG. 14 is an isometric view of a latching system formed in accordance with an embodiment of the present invention. The latching system shown in FIG. 14 may be used with the receptacle connector  100  and/or the plug connector  200 . As shown in FIG. 14, the latch recesses  650  include clearance areas  662  defined between side walls  668  of the latch members  130  and the latch flexion limiting lips  660 . The clearance areas  662  provide an area over which the latch members  130  may move in relation to the floating interface  620 . The clearance areas  662  are wider proximate the flex ends  654  of the latch members as compared to the retained areas  656 . That is, the latch members  130  are more securely retained at their retained ends  656  as compared to their flex ends  654 . The floating interface housing  620  moves in response to the movement of the flex portions  112  of the receptacle wafers  110 . That is, movement of the floating interface housing  620  through the clearance areas  662  causes a corresponding relative movement in the latch members  130 . That is, the cover  610  and base  120  remain stationary while the floating interface housing  620  moves. Movement between the latch member  130  and the latch flexion limiting lips  660  is relative to the actual movement of the floating interface housing  620 . However, relative movement of the latch member  130  is limited by the latch flexion limiting lips  660 . That is, as the latch members  130  contact the latch flexion limiting lips  660 , continued movement of the floating interface  620  in that direction is arrested. 
     FIG. 7 is an isometric view of a plug connector  200 , without plug wafers  110 , formed in accordance with an embodiment of the present invention. The plug connector  200  includes the base  220 , a floating interface housing  720  and a cover  710 . The floating interface housing  720  has latch recesses  750  having latch projections  752 , latch flexion limiting lips  760 , side walls  722 , a top wall  724 , a bottom wall  726  and an interface wall  728 . The latch recesses  750  and latch projections  752  are formed on the exterior of the top wall  724  and the bottom wall  726 . At least one of the side walls  722  includes slots  732  extending from the interface wall  728 . The slots  732  securely retain the interface portions  217  of the plug wafers  210 . Thus, upon complete assembly of the plug connector  200 , each plug wafer  210  is fixed at its rear portion  213  and its interface portion  217 . Only the flex portion  212  of each plug wafer  210  flexes, while the rear portion  213  and the interface portion  217  remain relatively rigid and straight as compared to the flex portion  212 . However, as mentioned above, while the interface portion  217  remains in a straight orientation, the interface portion  217  moves in response to the flexing of the flex portion  112 . 
     The plug wafers  210 , however, do not pass through the interface wall  728 . Rather, the interface wall  728  includes guide members  780  that support and align the single beam receptacle interconnects  14  of the ground terminals  22  and the double beam receptacle interconnects  24  of the signal terminals  22  so that they may pass through channels  778  formed within the interface wall  728 . The single beam receptacle interconnects  14  and the double beam receptacle interconnects  24  are exposed and may mate with contact pads on receptacle wafers  110  when the plug connector  200  mates with the receptacle connector  100 . 
     The cover  710  includes a top wall  712 , side walls  716 , a rear wall  714 , latch members  230  and cover latches  742 . An open cavity (not shown) is defined by the walls  712 ,  716  and  714 . In FIG. 7, the latch mating members  223  and cover mating notches  222  are formed on the side walls  216  of the base  220 . As shown in FIG. 2, however, the latch mating members  223  and cover mating notches  222  may be formed on the rear wall  208  of the base  220 . Alternatively, these features may be located on the side walls  216  and the rear wall  208 . The cover latches  742  are oriented on the cover  710  to correspond to the position(s) of the cover mating notches  222  and the latch mating members  223 . The cover latches  742  are received by the cover mating notches  222  and retained by the latch mating members  223 . Optionally, instead of using a latching system to fasten the cover  710  to the base  220 , the cover  222  may be fastened to the base  220  through screws, glue, and the like. 
     The latch members  230  may be integrally formed with the top wall  712  of the cover  710 , or they may be separately mounted on the top wall  712 . The latch members  230  on the cover  710  and on the base  220  have a flex end  754  and a retained end  756 . The latch members  230  engage the latch recesses  750  and mate with the latch projections  752 . The retained ends  756 , which are retained by the latch recesses  750 , remain fixed while the flex ends  754  may move, relative to the actual movement of the floating interface housing  720 , in the directions denoted by line B. That is, the flex ends  754 , because they are connected, or formed integrally with the stationary cover  710  or base  220 , do not actually move. The floating interface housing  720  moves, which produces relative motion between the flex ends  754  and the floating interface housing  720 . The movement of the flex ends  754  is limited by the latch flexion limiting lips  760 . As mentioned above, the movement of the latching system used with the plug connector  200  is similar to that used with the receptacle connector  100 . When the movement of the floating interface housing  720  causes the flex ends  754  of the latch members  230  to contact the latch flexion limiting lips  760 , continued movement of the floating interface in that direction is arrested. 
     The receptacle connector  100  is mated with the plug connector  200  so that electrical signals may travel from plug wafers  210  to receptacle wafers  110 , and vice versa. That is, the receptacle connector  100  receives and snapably retains the plug connector  200 , such that the receptacle wafers  110  orthogonally mate with the plug wafers  210 , as shown in FIG.  5 . The mating of the receptacle connector  100  with the plug connector  200  provides contact alignment correction over all angles and orientations because the floating interface  620  of the receptacle connector  100  may move over a horizontal plane (denoted by line A) and the floating interface  720  of the plug connector  200  may move over a vertical plane (denoted by line B). Thus, vertical misalignment, horizontal misalignment, or combinations of both, may be corrected through the floating interface housings  620  and  720  of the receptacle and plug connectors  100  and  200 , respectively. 
     The floating interface configuration may also be used with an electrical connector that mates plug and receptacle wafers in a coplanar fashion. That is, the plug and receptacle wafers are not orthogonally mated. FIG. 10 is an isometric view of the receptacle connector  100  mating in a coplanar fashion with a plug connector  1000 , according to an embodiment of the present invention. The plug connector  1000  includes many of the same features as the plug connector  200 , as described above, except it has wafer slots  1002  formed on a top housing  1016  of the cover  1010 . Alternatively, the wafer slots  1002  may not be included within the top housing  1016 . The wafer slots  1002  assist in retaining the plug wafers (not shown). Both the receptacle wafers  110  and the plug wafers, in this embodiment, are aligned in a coplanar fashion. That is, the receptacle wafer  110  that mates with its corresponding plug wafer is initially aligned in the same plane as the plug wafer. The interface housing  620  of the receptacle connector  100  may move in the directions denoted by Line A, while the interface housing (covered by the interface housing  620  of the receptacle connector  100 ) of the plug housing  1000  may move in the directions denoted by Line B. 
     FIG. 11 is an isometric view of a plug connector  1000  according to an embodiment of the present invention. As shown in FIG. 11, the plug connector  1000  does not have the wafer slots formed in the top housing  1016  of the cover  1010 . Rather, wafer slots  1102  are formed in the floating interface housing  1120 . The plug connector  1000  includes an alternative latching system. The floating interface housing  1120  includes a latching recess  1142  and a latching projection  1144 . The cover  1010  includes a latching member  1132  having a flex end  1134  and a retained end  1136 . The movement of the latching member  1132  and the latching projection  1144  function in a similar way as those described above with respect to FIGS. 1-9. However, the floating interface  1120  also includes a float-limiting divot  1150  and a float-limiting wall  1152 . Additionally, the latching member  1132  includes an abutting member  1160  that may move through the float-limiting divot  1150  until it abuts the floating limiting wall  1152 . Thus, the movement of the latching member  1132  is limited by the float limiting walls  1152 . Additionally, as shown in FIG. 11, a stationary intermediate piece  1188  may be used to ensure that the cover  1010  does not move. The alternative latching system shown in FIG. 11 may also be used with the receptacle connector  100  or the plug connector  200 . 
     Alternatively, various engagement systems may be used with the connectors  100 ,  200  and  1000  in lieu of the latching systems described. For example, a guide track system may be used in which an interface housing includes guide track(s) and the corresponding cover includes channel(s) that receive the guide track. The interface housing may then slide along the channel(s) on the guide tracks(s). Additionally, stop blocks may be positioned on the guide track(s) and/or channel(s) that limit the movement of the interface housing. Optionally, the guide tracks may either be smooth or include a gear system in which the guide track has gear teeth that are engaged by a gear, or cog. Also, alternatively, instead of using a latching system, fasteners, such as screws, may be used. That is, the interface housing may be screwed to the cover such that the interface housing may move over the cover. For example, the interface housing may be screwed to the cover at a mid point of the top wall of the interface housing, and the interface housing may be screwed to the base at a mid point of the bottom wall of the interface housing. The two screws would be positioned along the same axis, thereby providing a rotational axis over which the interface housing may move. A clearance area between the interface housing and the cover may also be used to provide additional range of motion. 
     FIG. 12 is an isometric view of an interior of the plug connector  1000  according to an embodiment of the present invention. The plug wafers  1200  are connected to signal terminals  1222  and ground terminals  1212 . Each signal terminal  1222  includes a double beam receptacle interconnect  1224  extending from an intermediate portion  1226 , and a single beam plug signal interconnect  1228  extending from an opposite end of the intermediate portion  1226 . Each double beam receptacle interconnect  1224  connects to one side of a receptacle wafer (not shown), while each single beam plug signal interconnect  1228  connects to one side of a plug wafer  1200 . Each ground terminal  1212  includes a single beam receptacle interconnect  1214  extending from an intermediate portion  1216  connecting to a second side of a receptacle wafer (not shown) and a wide plug ground interconnect  1218 , which connects to one side of a plug wafer  1200 . The plug ground interconnect is wider than the plug signal interconnect  1228 . 
     FIG. 13 is a side view illustrating movement of signal and ground terminals  1222  and  1212  during an upward shift of a receptacle wafer  110 , according to an embodiment of the present invention. As shown in FIG. 13, when a receptacle wafer moves, for example, in the up direction, and the plug wafer  1200  remains stationary, the plug signal interconnect  1228 , the movement of which is limited by stop blocks  1302 , pivots, in a cantilever fashion, due to the movement of the receptacle wafer  110 . The stop blocks  1302  may be formations that outwardly extend from the plug wafer  1200 . A retained end  1260  of a plug signal interconnect  1228  engages a signal contact pad  1261 , which is positioned between two stop blocks  1302 . The retained end  1260  is positioned between two signal blocks  1302 . Thus, the movement of the receptacle wafer  110  shifts the plug signal interconnect  1228  out of a level orientation. Conversely, the ground terminal  1212  remains in a level orientation because the ground terminal  1212  slides up or down on the plug wafer  1200  in response to the movement of the receptacle wafer  110 . Because, however, the plug ground interconnect  1218  is wider than the plug signal interconnect  1228 , the plug ground interconnect  1218  is able to shield the plug signal interconnect  1228  from other plug signal interconnects  1228  despite the cantilever movement of the plug signal interconnects  1228 . 
     Thus certain embodiments of the present invention provide an electrical connector that maintains proper contact between electrical wafers included within a first connector and those in a second connector, whether the wafers of the first connector mate orthogonally, or in a coplanar fashion with those of thee second connector. Further, certain embodiments of the present invention provide an electrical connector that maintains proper alignment and corrects misalignments between circuit boards, or wafers, within a first connector and those of a second connector housing. 
     While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.