Patent Publication Number: US-7905731-B2

Title: Electrical connector with stress-distribution features

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related by subject matter to U.S. patent application Ser. No. 12/054,023 filed Mar. 24, 2008, and is also related by subject matter to U.S. patent application Ser. No. 12/109,750 filed Apr. 25, 2008. 
     FIELD OF THE INVENTION 
     Generally the invention relates to electrical connectors. More particularly the invention relates to power connectors. 
     BACKGROUND OF THE INVENTION 
     A Power connector for transmitting electrical power may be mounted onto a printed circuit board (“PCB”) using a press fit. The press fit application of the connector may generate some concerns about the contact deformation and damage to the housing, especially on a vertical receptacle or header connector. More particularly, if a large enough gap exists between the contact beams of the contacts and the interior walls of the housing, the middle portions of the press-fit tails may arc or bow away from the PCB during mounting of the connector onto the PCB. 
     For example,  FIGS. 1A and 1B  depict the relationship between a contact  10  and a housing  14  of a prior art connector. As depicted, the contact  10  has a body  16  and a plurality of contact beams  18  extending from a first edge  20  of the body  16 . When the contact  10  is mounted in the housing  14 , a large gap  24  exists between an edge  28  of a first contact beam  32  of the plurality of contact beams  18  and an upper sidewall  36  of the housing  14 . Further, when the contact  10  is mounted in the housing  14 , a large gap  40  exists between an edge  44  of a second contact beam  48  of the plurality of contact beams  18  and a lower sidewall  52  of the housing  14 . When the press pins (not shown) of the contact  10  are pressed into a substrate (not shown), the body  16  of the contact  10  may arc or bow. A middle point  56  of the body  16  may displace about 0.246 mm due to the arcing or bowing of the contact  10 .  FIG. 1C  depicts a bowed or arced contact  10 . Because the body  16  is bowed, the contact beams  18  spread apart causing different sized gaps  58  between adjacent contact beams  18 . Accordingly, a need exists for features that reduce or eliminate such arcing or bowing of the body  16  may be desired. 
     SUMMARY OF THE INVENTION 
     Disclosed herein is an electrical connector that may be capable of inhibiting bowing of the contacts of the connector when the connector is mounted on a substrate. Such a connector may include a housing and a contact mounted in the housing. The contact may include a body, a plurality of terminal pins extending from a first edge of the body and a plurality of contact beams extending from a second edge of the body. At least a portion of the edges of a first contact beam and of a second contact beam may be positioned proximate respective adjacent surfaces of the housing when the connector is not mounted on the substrate. Contact between the at least a portion of the edges of the first and second contact beams and their respective adjacent surfaces of the housing during mounting of the connector on the substrate may restrain the contact beams and may inhibit bowing of the body of the contact. The contact beams may be arranged in a substantially linear array and the first and second contact beams may be located at respective first and second ends of the substantially linear array. 
     In another embodiment of the connector, the body of the contact may include a flared portion. The flared portion may be positioned proximate an adjacent surface of the housing when the connector is not mounted on the substrate. Contact between the flared portion and the surface of the housing adjacent the flared portion during mounting of the connector on the substrate may inhibit bowing of the body of the contact. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of a connector system depicting the relationship between a connector housing and a contact assembly found in the prior art. 
         FIG. 1B  is a side view of the connector system of  FIG. 1A . 
         FIG. 1C  is a side view of the connector system of  FIG. 1A  depicting a bowed contact. 
         FIG. 2A  is a front perspective view of an exemplary embodiment of a connector. 
         FIG. 2B  is a back perspective view of the connector shown in  FIG. 2A . 
         FIG. 3  is a perspective view of a contact. 
         FIG. 4  is a side view of a first half of a contact. 
         FIG. 5  is a partial bottom view of the first half of the contact of  FIG. 4 . 
         FIG. 6  is a perspective view of the first half of the contact of  FIG. 4  positioned to combine with a second half of a contact. 
         FIG. 7  is a cut away view of an example embodiment of a connector depicting the relationship between a housing and the contact of  FIG. 3 . 
         FIG. 8  is a partial top view of the connector of claim  7  depicting the relationship between the flared portions of the contact of  FIG. 3  and the housing. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
       FIGS. 2A and 2B  depict an example embodiment of a connector  60  having several contacts  62  mounted in a housing  66 . As illustrated the contacts  62  may include several terminal pins  72 . Additionally, the connector  60  may include an array of signal contacts  76  located between the contacts  62 . When the terminal pins  72  are press fit onto a substrate, the connector  60  may inhibit bowing of the contacts  62 . The particular configuration of connector  60  shown, is disclosed for exemplary purposes only. For example, while the connector  60  is depicted with six contacts  62 , the connector  60  is not limited to such a number, and may include any number of contacts  60 . Furthermore, while the particular connector  60  depicted is a vertical receptacle connector, the connector  60  is not limited to such an embodiment, and may include other configurations. 
       FIG. 3  depicts an example embodiment of a contact  100  capable of being mounted in a connector housing. The contact  100  may be made from an electrically conductive material, such as metal. The contact  100  may be a power contact. As depicted, the contact  100  may include a first half  104  and a second half  106 . While the contact  100  is depicted as comprising two halves, the contact  100  is not limited to such a design and may be manufactured as a single unitary structure. 
       FIGS. 4 and 5  are more detailed views of the first half  104  of the contact  100 . As depicted, the first half  104  may include a body  116 , a plurality of terminal pins  120  extending from a first edge  124  of the body  116 , and a plurality of contact beams  128  extending from a second edge  132  of the body  116 . 
     As depicted, the body  116  may include a thru hole  134 , a dimple  136  and a flared portion  138 . The thru hole  134  may be formed in a first end  139  of the body  116 , and the dimple  136  may protrude from a second end  140  of the body  116 . The first end  139  may be opposite to the second end  140 . The function of the thru hole  134  and the dimple  136  is explained below in connection with  FIG. 6 . 
     The terminal pins  120  may be capable of being received by penetrations in a substrate (not shown). The terminal pins  120  may be eye-of-the-needle press-fit pins. As best shown in  FIG. 5 , the terminal pins  120  of the first half  104  may be offset by the flared portion  138 . As depicted, the flared portion  138  of the first half  104  may flare out in a first direction from the body  116 . 
     The contact beams  128  may each be designed to have a specific structure. For example, the first half  104  may include two angled contact beams  142  and three substantially straight contact beams  144 . The angled contact beams  142  and the straight contact beams  144  may be arranged in a staggered or alternating manner, i.e. each angled contact beam  142  may be positioned adjacent to a straight contact beam  144 . Furthermore, the angled contact beams  142  may include a flared portion  148  at a first end  152  of the contact beams  142 . An example angle in which the angled beam  142  may be formed can be seen in  FIG. 5 . The first half  104  is not limited to five contact beams  128  as depicted, and may include any number of contact beams  128 . Furthermore, the first half  104  is not limited to alternating angled beams  142  and straight beams  144 . For example, the first half  104  may have all angled beams  142  or all straight beams  144 . 
       FIG. 6  depicts the first half  104  and the second half  106  positioned to combine and form the contact  100 . As depicted, the second half  106  may be identical to the first half  104  but may be rotated 180 degrees. Accordingly, like the first half  104 , the second half  106  may have a body  216 , a plurality of terminal pins  220  extending from a first edge  224  of the body  216 , and a plurality of contact beams  228  extending from a second edge  232  of the body  216 . In combination, the thru hole  134  of the first half  104  may receive a dimple  234  protruding from a first end  239  of the body  216  of the second half  106 , and the dimple (not shown in  FIG. 6 ) of the first half  104  may engage a thru hole  236  formed in a second end  240  of the body  216  of the second half  106 . 
     The body  216  of the second half  106  may also include a flared portion  244 . As depicted, the flared portion  244  may flare out from the body  216  of the second half  106 . The flared portion  244  may flare out from the body  216  in a direction opposite of the flared portion  138  formed in the first half  104 . That is, flared portion  244  may extend in one direction, while flared portion  138  may extend in the opposite direction. 
     The contact beams  228  of the second half  106  may also include angled contact beams  248  and straight contact beams  252 . When the first half  104  is combined with the second half  106 , the angled beams  142  of the first half  104  may align with the angled beams  248  of the second half  106 . Similarly, the straight beams  144  of the first half  104  may align with the straight beams  252  of the second half  106 . When the first half  104  and the second half  106  are combined, the combination may form a plurality of contact beam pairs  260  as depicted in  FIG. 7 . 
       FIG. 7  depicts contact  100  mounted in a housing  300 . The housing  300  may be made from a dielectric material such as a plastic for example. As depicted, the housing  300  may have a first sidewall  304  and a second sidewall  308 . When the contact  100  is mounted in the housing  300 , an edge  312  of a first contact beam  316  of the plurality of contact beam pairs  260  may be positioned proximate the first sidewall  304 . Additionally, when the contact  100  is mounted in the housing  300 , an edge  320  of a second contact beam  324  of the plurality of contact beam pairs  260  may be positioned proximate the second sidewall  308 . As depicted, the edge  312  of the first contact beam  316 , and the edge  320  of the second contact beam  324  may abut the first and second sidewalls  304 ,  308  of the housing  300 . Alternatively, the edge  312  of the first contact beam  316 , and the edge  320  of the second contact beam  324  may define a gap (not shown) with the respective first and second sidewalls  304 ,  308 . The gap defined between the edge  312  of the first contact beam  316  and the first sidewall  304  and the gap defined between the edge  320  of the second contact beam  324  and the second sidewall  308  may be up to about 2 thousandths of an inch wide. Increasing the gap may increase the probability of bowing. Accordingly, there is preferably no gap. 
     The terminal pins  120 ,  220  of the contact  100  may be pressed into a substrate (not shown). During insertion of the terminal pins  120 ,  220  into the substrate the relationship (i.e. close proximity of) between the edge  312  of the first contact beam  316  and the first sidewall  304 , and the relationship (i.e. close proximity of) between the edge  320  of the second contact beam  324  and the second sidewall  308  may help inhibit bowing or arcing of the contact  100 . For example, the relationship may limit the deflection of the contact beam pairs  260  in directions substantially perpendicular to the direction in which the contact beam pairs  260  extend. Inhibiting the bowing of the contact  100  may not only limit the deflection of the contact beam pairs  260  but may also create a substantially uniform distribution of stress during press-fit of the terminal pins  120 ,  220  onto the substrate. 
       FIG. 8  depicts the relationship between the flared portions  138 ,  244  and the housing  300 . As depicted the housing  300  may include an aperture  330  having a first side wall  334  and a second sidewall  338 . When the contact  100  is mounted in the housing  300 , an edge  342  of the flared portion  138  of the first half  104  may be positioned proximate the first sidewall  334  of the aperture  330 . Additionally, when the contact  100  is mounted in the housing  300 , an edge  346  of the flared portion  244  of the second half  106  may be positioned proximate the second sidewall  338  of the aperture  330 . As depicted, the edge  342  of the flared portion  138 , and the edge  346  of the flared portion  244  may abut the first and second sidewalls  334 ,  338  of the aperture  330 . Alternatively, the edge  342  of the flared portion  138 , and the edge  346  of the flared portion  244  may define a gap (not shown) with the respective first and second sidewalls  334 ,  338  of the aperture  330 . The gap defined between the edge  342  of the flared portion  138  and the first sidewall  334  and the gap defined between the edge  346  of the flared portion  244  and the second sidewall  338  may be up to about 2 thousandths of an inch wide. Increasing the gap may increase the probability of bowing. Accordingly, there is preferably no gap. 
     During insertion of the terminal pins  120 ,  220  into the substrate, the relationship (i.e. close proximity of) between the edge  342  of the flared portion  138  and the first sidewall  334 , and the relationship (i.e. close proximity of) between the edge  346  of the flared portion  244  and the second sidewall  338  may further help inhibit bowing or arcing of the contact  100 . Inhibiting the bowing of the contact  100 , as noted above, may limit the deflection of the contact beam pairs  260  and may create a substantially uniform distribution of stress during press-fit of the terminal pins  120 ,  220  onto the substrate. 
     The foregoing description is provided for the purpose of explanation and is not to be construed as limiting the invention. While the invention has been described with reference to preferred embodiments or preferred methods, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Furthermore, although the invention has been described herein with reference to particular structure, methods, and embodiments, the invention is not intended to be limited to the particulars disclosed herein, as the invention extends to all structures, methods and uses that are within the scope of the appended claims. Those skilled in the relevant art, having the benefit of the teachings of this specification, may effect numerous modifications to the invention as described herein, and changes may be made without departing from the scope and spirit of the invention as defined by the appended claims.