Patent Publication Number: US-8535069-B2

Title: Shielded electrical connector with ground pins embeded in contact wafers

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is related to a prior patent application which is filed on Aug. 23, 2010, application Ser. No. 12/861,131 and entitled “SHIELDED ELECTRICAL CONNECTOR”. The inventor of the present patent application is one of three inventors of the prior patent application. Those two applications will assign to a same assigner, Hon Hai Precision IND CO., LTD. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a shielding electrical connector, and more particularly to an electrical connector with a row of ground contacts or shielding contacts embedded in terminal wafers. 
     2. Description of Related Art 
     A shielded electrical connector is provided having several rows of contacts inside the housing and outer metallic shell for the purpose of shielding. Such shielded electrical connectors are widely used in computers, work stations and other types of electronic office equipment for the connection of signal-carrying lines. In such shielded electrical connectors, the metal shell prevents electromagnetic noise from penetrating into the connector, but it does not eliminate the problem related to cross-talk between contact pins. 
     Hence, it is desired to provide an electrical connector to overcome the problems mentioned above. 
     BRIEF SUMMARY OF THE INVENTION 
     An electrical connector assembly comprises a receptacle connector and a plug connector intended to mate with the receptacle connector. The receptacle connector comprises a connector housing defining two parallel mating slots vertically spaced from each other and a plurality of terminal wafers juxtaposedly loaded in the connector housing. Each terminal wafer comprises an upper pair of contacting portions and a lower pair of contacting portions, the upper pairs of contacting portions of the plurality of terminal wafers exposing and the lower pairs of contacting portions of the plurality of terminal wafers exposing to the two mating slots respectively. Each of said terminal wafers further defines a ground contact with a contacting portion disposed between the upper pair and lower pair of the contacting portions. The plurality of terminal wafers comprises pairs of differential signal wafers and ground wafers which are arranged in an alternating sequence in the connecting housing. The plug connector comprises two card edges intended to be inserted in the mating slots respectively and a ground plate with a row of contacting pin vertically spaced between said two card edges. The contacting pins of the ground plate touch with pairs of ground contacts formed with two adjacent ground contacts in two adjacent terminal wafers. 
     Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an electrical connector assembly according to the present invention, which includes a receptacle connector and a plug connector; 
         FIG. 2  is a perspective view of the receptacle connector shown in  FIG. 1 ; 
         FIG. 3  is a perspective view of the connector housing of the receptacle connector, the metal cage is removed; 
         FIG. 4  is a perspective view of a set of terminal wafers used in the connector housing; 
         FIG. 5  is a same view to  FIG. 4 , but illustrating from another view; 
         FIG. 6  is a perspective view of the plug connector shown in  FIG. 1 ; 
         FIG. 7  is a perspective view of a mating end of the plug connector; 
         FIG. 8  is an exploded perspective view of ground plate; 
         FIG. 9  is a cross-section view of the electrical connector assembly taken along lines  9 - 9  shown in  FIG. 1 ; and 
         FIG. 10  is a cross-section view of the electrical connector assembly taken along lines  10 - 10  shown in  FIG. 1 ; 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Reference will be made to the drawing figures to describe the present invention in detail, wherein depicted elements are not necessarily shown to scale and wherein like of similar elements are designated by same or similar reference numeral through the several views and same or similar terminology. 
     Referring to  FIG. 1 , an electrical connector assembly  1000  according to a preferred embodiment of the present invention is disclosed, which is compliable to a Mini Multilane Shielded Integrated HD Connector for use in high speed serial, interconnect applications at speeds up through 12 Gigabits/second, written in SFF 8644 Specification by Molex Incorporation, which is also named as Mini SAS HD external. The assembly  1000  includes a receptacle connector  101  and a plug connector  102  mated with each. The receptacle connector  101  is mounted on and electrically connected to a printed circuit board (PCB)  103  which is assembled in a system end, and the plug connector  102  is electrically coupled to cables  104 . The plug connector  102  disconnects from the receptacle connector  101  by a pull tab  61 . 
     Referring to  FIGS. 2-5 , the receptacle connector  101  has a connector housing  10  and a metal cage  30  surrounding the connector housing  10 . The cage  30  is in a form of rectangle and has a front mating opening  31  through which the plug connector  102  is inserted in mating slot  111  defined in the connector housing  10 . A metal gasket  32  is formed at an outer periphery of the mating opening  31 . The cage  30  has an opening (not labeled) in a rear bottom wall thereof so the connector housing  10  is located in the mating opening  31 , thereby being mounted on the PCB  103  with press-fit tail portions  212  of terminals which will be described hereinafter. The cage  30  extends a plurality of press-fit solder legs  33  which are intended to be inserted in the PCB  104 . 
     The connector housing  10  is formed in two insulating pieces, a front/first section  11  and a rear/second second section  12 . The first section  11  includes openings shown in the form of said mating slots  111  running through a front face  112  thereof. The two mating slots  111  into which edge cards  41  of the plug connector  102  as shown in  FIG. 6  may be inserted, are disposed parallel to each other in a vertical direction or stacked vertically. A plurality of terminal wafers  20  e.g., a set of wafers  20  that are arranged in side-by-side order are assembled in the connector housing  10 . Each wafer  20  supports a plurality of conductive terminals  21  that each includes a contacting portion  211  in a contacting beam form, a tail portion  212  and a body portion  213  interconnecting the contacting portion and tail portions  211 ,  212  together. The body portions  213  are embedded in the insulating supports  23 , the contacting portions and the tail portion extend beyond a front edge and a bottom edge of the terminal wafers respectively. The plurality of wafers  20  is inserted into the first section  11  from a back of the first section  11  of the connector housing  10  and the second section  12  are covered at the back of the first section to protect the wafers  20 . The contacting portions  211  of the terminals of the wafers are located in passageways  113  defined on two opposite inner sides of the mating slots  111  respectively. The tail portions  212  expose to a mounting edge of the receptacle connector  101 . The insulating support  23  defines a groove  231  running through the body portions  213  adjacent to the tail portions to expose somewhat of the body portions. 
     Referring to  FIGS. 6 through 8 , the plug connector  101  includes a mating end  40  with two parallel card edges  41  which are intended to be inserted in the mating slots  111  of the receptacle connector  101 . The two card edges  41  space from each other in the vertical direction and are embedded with conductive pads  42  on the two surface of the front edge of the card edges  41 , thereby slide with the contacting portions  211  of the receptacle connector when the plug connector  102  is inserted in the receptacle connector  101 . The cables  104  are connecting with conductive pads (not shown) on the back edge of the mating end  40  of the plug connector. When the mating end  40  of the plug connector  101  is inserted in the mating slots  111  of the receptacle connector  102  as best shown in  FIG. 9 , the contacting portions  211  in the opposite inner sidewall of the mating slots  111  are engaged with the conductive pads of the card edges  41  by clamping. Moreover, a row of ground terminals  22  of the receptacle connector  101  are connected with corresponding contacting pins disposed between said two card edges  41  to decrease cross talk between the terminals, which will be introduced hereinafter. 
     Referring to  FIGS. 4 and 5 , three pairs of first wafers identified by reference numeral  24  is installed between second wafers identified by reference numeral  25 . The pair of first wafers  24  is two single signal wafers  24  disposed alongside so that said two adjacent signal wafers  24   a ,  24   b / 24   c ,  24   d / 24   e ,  24   f  are configured as a differential signal pair and the wafer  25  is a ground wafer. The signal wafers  24  are intended to carry multiple signal signals, and particularly, pairs of differential signals. The ground wafers  25  are intended to be connected to one or more ground planes on the PCB and its terminals will carry ground signals as opposed to differential signals. Therefore the plurality of wafers carries signals in a pattern “ground, signal+, signal−, ground”. Said terminals  21  embedded in the wafers are identical except for their relative size, for brevity. The ground wafer  25  is higher than the signal wafers  24 . 
     Each wafer  24 / 25  is embedded with four said terminals  21  aligned with each other in a vertical plane thereof. The upper two terminals are configure as an upper pair  215  of the terminals which are mirrored images of each other, all of the contacting portions  211  slant toward each other so that the upper pairs  215  of the terminals are co-linear along a longitudinal of the mating slots  111  and received in the passageways  112  of the upper mating slots. The lower two terminals are configure as a lower pair  216  of the terminals which are mirrored images of each other, all of the contacting portions  211  face toward each other so that the lower pairs of the terminals are aligned in a line and received in the passageways  112  of the lower mating slots  111 . The terminals in a same row are aligned along a transverse or horizontal line, not long the contacting portions but also the body portions and tail portions. One terminal of one of the pair of differential signal terminal wafers and one terminal of the other one of the pair of differential signal terminal wafers cooperate to carry an equal but opposite polarity signal and so the same to other three terminal. Each of the terminals of each ground wafer carry ground signal between each pair of differential terminal. The insulating support  23  defines two supporting potions  231  extending forwards from a front edge thereof, which are disposed between the two contacting portion  211  of the upper pair and lower pair respectively to enhance the stability of the contacting portions. 
     Each wafer  24 / 26  further is embedded with a ground contact  22  between the lower pair and the lower pair of the terminals  21 . The ground contact  22  includes a contacting portion  221 , a tail portion  222  and body portion (not labeled) connecting with the contacting portion  221  and the tail portion  222 . The contacting portion  221  slant toward one adjacent contacting portion  221  of the grounding contact of the adjacent terminal wafer, such as terminal wafers  24   b ,  25   a , so that as best shown in  FIG. 10 , the two contacting portions  221  are configured as one mating pair  226  thereby forming a mating channel to accommodate a corresponding contacting pin  51  of the plug connector  102 . Two adjacent contacting portions  221  have a transverse mating direction A which is perpendicular to a vertical mating direction B of the pairs of terminals of the wafer. In the vertical mating direction, the contacting portions of the ground contacts are engaged with the plug connector  103  no later than the contacting portions of the terminals to arrive a good engagement of said two connectors, in this preferred embodiment, the contacting portions  211  of the terminals and the contacting arm  221  of the ground contact are co-linear in the vertical mating direction B. The ground contact  22   a  of the terminal wafer  24   a  or one outmost terminal wafer slants outwards to contact with corresponding contacting pin  51   a . The contacting portions  221  of the ground contact  22  bend to offset along the transverse direction firstly and then reversely bend to remedy said offset, so that two adjacent contacting portions  221  have elasticity to engage with contacting pin. 
     The plug connector  101  further includes a ground plate  50 , which has a plurality of contacting pins  51  extending forward from the base  52  and parallel to the card edges  41 . The grounding plate  50  is retained in an insulating base  53  and then assembled in the plug connector. The base defines two recesses  521  at two transverse sides and two holes  522  between the transverse sides to fitly retain in the insulting base. The contacting pins  51  are arranged in one row parallel to and between the card edges  41 . The contacting pins  51  are inserted in the corresponding mating pair  226  of the ground contacts to achieve an engagement. Combination with  FIG. 3 , the receptacle connector  101  defines a row of opening  114  running through the front face  112 , the mating pairs  226  of the grounding contacts  22  are aligned with corresponding openings  114  so as to receive the corresponding contacting pins  51  of the plug connector. The body portions and the tail portion of the ground pin are similar to that of the terminals so that all of them are parallel to each other. The ground contacts  22  and the ground plate  50  benefit cross talk between the upper pairs and lower pairs of the terminal. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.