Abstract:
An electrical connector ( 100; 200 ) mounted on a printed circuit board includes an insulative housing ( 10; 20 ), a pair of shells ( 18, 19; 30, 31 ) and a number of terminals ( 15, 16; 26, 27 ) received in the housing. The housing comprises a mating portion ( 11; 22 ) defining a pair of parallel sidewalls extending longitudinally. Each shell ( 18; 30 ) comprises a flat portion ( 181; 301 ) which provides a plurality of spaced latches ( 186; 305 ) bent inwardly from a top thereof for retaining the shell on the housing. The separately formed shells can provide good EMI protection and be manufactured easily and cheaply.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is related to an electrical connector, and more particularly to a shielded board-mounted electrical connector having an improved shielding shell. The invention relates to the copending applications titled “ELECTRICAL CONNECTOR” and “ELECTRICAL CONNECTOR HAVING IMPROVED ELECTROSTATIC DISCHARGE PROTECTION” having the same application and the same assignee with the instant invention. 
   2. Description of Related Art 
   An electrical connector electrically connected to a printed circuit board is often equipped with a metal shield for shielding electrical contacts mounted therein and for avoiding Electro-Magnetic Interference (EMI). U.S. Pat. No. 5,921,814 (named as the &#39;814 patent for simplification) discloses such kind of electrical connector assembly which generally includes a receptacle connector and a plug connector mated with each other. 
   As shown in FIGS. 1–3 of the &#39;814 patent, the receptacle connector 20 includes an elongated dielectric housing, two rows of terminals received in spaced arrays longitudinally of the dielectric housing and a one-piece conductive shield assembled on the housing. The housing 26 includes a mating portion for mating with a corresponding portion of the plug connector. The mating portion has a pair of long sidewalls 32 a  which extend generally parallel to each other along a longitudinal direction of the housing and a pair of short end walls 32 b  which extend generally parallel to each other along a lateral direction of the housing. The sidewalls and the end walls define an elongated plug-receiving slot 34 therebetween. The metal shield 44 has a plate portion 58 juxtaposed against an inside surface of the long sidewalls and short end walls of the dielectric housing. 
   As shown in FIGS. 6–7, and 10 of the &#39;814 patent, the plug connector 22 includes an elongated dielectric housing, two rows of terminals received in spaced arrays longitudinally of the dielectric housing and a one-piece conductive shield assembled on the housing. The housing includes opposite end portions extending longitudinally outwardly from a central mating portion thereof. The mating portion of the plug connector comprises a pair of parallel long sidewalls 78 a  extending longitudinally and a pair of parallel short end walls 78 b  extending laterally to define a generally hollow, elongated opening. The metal shield 90 has an elongated plate portion 92 substantially surrounding the mating portion of the housing of the plug connector. When the plug connector is mated with the receptacle connector, the plate portions of the shields of the receptacle connector and the plug connector together define a closed loop, which encloses the terminals inside, to provide EMI protection. 
   However, each of the shields of the plug connector and of the receptacle connector is formed by drawing technology during the process of being stamped and molded. Using drawing technology, a designer must make more effort to design a die which is costly and the manufacture of the shield is still difficult. 
   Hence, an improved shielded board-mounted electrical connector is required to overcome the above-mentioned disadvantages of the related art. 
   SUMMARY OF THE INVENTION 
   A major object of the present invention is to provide an improved board-mounted electrical connector having a shielding shell which is cost efficient and easily manufactured. 
   In order to achieve the object set forth, an electrical connector in accordance with the present invention comprises an elongated housing having a mating portion and a plurality of terminal channels, a plurality of conductive terminals received corresponding terminal channels and a pair of shielding shells. The mating portion defines a receiving space surrounding by two longitudinally extended sidewalls and communicating with the terminal channels. Each sidewall defines a plurality of spaced notches in a top thereof and a plurality of recesses in a bottom thereof. Each shell comprises a flat portion for covering on an outside surface of the sidewalls of the mating portion. The flat portion has a plurality of spaced latches in a top thereof received in the notches and a plurality of grounding tails in a lower portion thereof extending through the recesses. 
   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 a receptacle connector of a connector assembly in accordance with the present invention; 
       FIG. 2  is an exploded, perspective view of the receptacle connector of  FIG. 1 ; 
       FIG. 3  is a perspective view of a plug connector of the connector assembly in accordance with the present invention; 
       FIG. 4  is an exploded, perspective view of the plug connector of  FIG. 3 ; 
       FIG. 5  is a cross-sectional view of the receptacle connector taken along line  5 — 5  of  FIG. 1 ; and 
       FIG. 6  is a cross-sectional view of the plug connector taken along line  6 — 6  of  FIG. 3 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made in detail to the preferred embodiment of the present invention. 
   Please refer to  FIGS. 1 and 3 , the feature of the present invention are shown in a connector assembly which includes a receptacle connector  100  and a plug connector  200 . 
   With reference to  FIGS. 1 and 2 , the receptacle connector  100  for mounting onto a surface of a printed circuit board (not shown) comprises an insulative housing  12 , a plurality of conductive terminals  15 ,  16  received in the insulative housing  12  and a pair of first and second shielding shell  18 ,  19  assembled on the insulative housing  12 . 
   The insulative housing  10  is elongated and comprises a rectangular mating portion  11  and end portions  12  disposed in two opposite ends of the mating portion  11 . The mating portion  11  includes a pair of long sidewalls  111  extending along a longitudinal direction of the insulative housing  10 , a pair of short end walls  112  extending generally along a lateral direction of the insulative housing  10  and a tongue plate  13  extending upwardly from a bottom wall of the mating portion  11 . The sidewalls and the end walls together define a generally rectangular receptacle  114  therebetween and the tongue plate  13  is located in a center of the receptacle  114 . A plurality of terminal channels  131 ,  132  and mating holes  133  are formed on two opposite surfaces of the tongue plate  13 . A plurality of spaced notches  117  are formed on an inside surface of the sidewalls  111 . Each end wall  112  forms a pair of taper-shaped guiding posts  14  extending upwardly from an upper end thereof and having a cutout  141  defined therebetween. Plural pairs of protrusions  115  are formed on an outside surface of the sidewalls  111  and each pair of protrusions form a recess  116  therebetween. The end portions  12  extend outwardly from the end walls  112  of the mating portion  11  and a pair of splits  182  are defined between the end portion  12  and the end wall  112 . The end portions  12  form locating legs  121  in a bottom thereof and extending downwardly. 
   The plurality of conductive terminals include a plurality of signal and power terminals  15 ,  16  respectively received in corresponding terminal channels  131 ,  132 . Each terminal  15 ,  16  includes a contact portion  151 ,  161  for engaging with a contact of the plug connector  200  and a tail portion  152 ,  162  extending downwardly from the contact portion  151 ,  161  beyond the mating portion  11  for mounting to the printed circuit board. 
   A metallic beam  17  is pole-shaped and includes an elongated base  171 , a plurality of tabs  172  extending from two opposite longitudinal sides of the base  171  for engaging with the mating holes  133  of the tongue plate  13  and grounding tabs  173  located at two opposite ends of the base  171 . 
   The first and the second shielding shells  18 ,  19  are assembled onto the mating portion  11  of the insulative housing  10  and have the same structure as each other. Each of shielding shells  18 ,  19  is stamped from a metal sheet and has a flat portion  181  for covering on the outside surface of the sidewalls  111  of the mating portion  11 , and a pair of opposite wings  182  extending laterally from opposite ends of the body  181  for covering outer sides of the end walls  112  of the mating portion  11  and electrically connecting with the grounding tabs  173  of the metallic beam  17 . The flat portion  181  disposes a plurality of grounding legs  184 . The grounding legs  184  are received in corresponding recesses  116  of the insulative housing  10  and then bent to form a grounding tail  185  for connecting the first and the second shielding shell  18 ,  19  to appropriate ground circuit traces on the printed circuit board. A plurality of spaced latches  186  extend inwardly and downwardly from a top of the flat body  181  for mating with the notches  117  of the insulative housing  10 . Each wing  182  forms a retention leg  183  extending downwardly from a bottom thereof with a retention tip  189  extending somewhat oblique to the retention leg  183  and received in a corresponding split  118 ,  119  of the end portion  12 . The oblique retention tip  189  can extend through a corresponding retention through hole in the oblique printed circuit board, on which the housing  10  is directly seated, in a perpendicular manner. The wing  182  further has a engaging finger  187  extending upwardly form a top thereof for being received in the cutout  141  of the insulative housing  10  and having a latching tail  188 . 
   In assembly, the terminals  15 ,  16  are inserted into corresponding terminal channels  131 ,  132  of the insulative housing  10  in a down-to-up direction. The first and the second shielding shells  18 ,  19  are assembled onto the insulative housing  10  in an up-to-down direction. The grounding legs  184  and the latches  186  of the shielding shells  18 ,  19  respectively engage with the recesses  116  and the notches  117  of the insulative housing  10  so that the shielding shell  18 ,  19  are firmly attached onto the insulative housing  10 . The wings  182  of the shielding shells  18 ,  19  join to each other to form a closed loop enclosing the sidewalls  111  and the end walls  112  of the mating portion  11  therein. Therefore, the shielding shells  18 ,  19  can provide good anti-EMI protection to the contact portions  151 ,  161  of the terminals  15 ,  16  located therebetween. 
   With reference to  FIGS. 3 and 4 , the plug connector  200  comprises an insulative housing  20 , a plurality of conductive terminals  26 ,  27  received in the insulative housing  20 , and first and second shielding shells  30 ,  31  assembled to the insulative housing  20 . 
   The insulative housing  20  is elongated and includes a mating portion  22 . The mating portion  22  comprises a pair of long sidewalls  222  which extend generally parallel to each other along a longitudinal direction of the insulative housing  20  and a pair of short end walls  23  which extend generally parallel to each other along a lateral direction of the insulative housing  20 . The sidewall  222  and the end walls  23  together define an elongated slot  24  therebetween. The sidewall  222  forms a plurality of supporting ribs  21  in a bottom thereof and extending outwardly, and recesses between two supporting ribs  21 , and defines a plurality of notches  221  in a top thereof and extending downwardly. A plurality of terminal channels  241 ,  242  are defined on an inside surface of the sidewalls  222 . The end walls  23  define a plurality of grooves  232 ,  233  respectively receiving metal plates  251 ,  252 . The end walls  23  don&#39;t connect with the sidewalls  222  and form a receiving room therebetween receiving grounding plate  281  extending downwardly beyond a bottom of the mating portion  22  for connecting with the printed circuit board. The end walls  23  form locating legs  212  extending downwardly for engaging with the printed circuit board. 
   The plurality of conductive terminals includes a plurality of signal and power terminals  26 ,  27  respectively received in corresponding terminal channels  242 ,  241 . Each terminal  26 ,  27  includes a contact portion  261 ,  271  for engaging with a contact of the receptacle connector  100  and a tail portion  262 ,  272  extending downwardly from the contact portion  261 ,  271  beyond the supporting ribs  21  for mounting to the printed circuit board. 
   The first and the second shielding shells  30 ,  31  are assembled onto the mating portion  22  of the insulative housing  10  and have the same structure as each other. Each of shielding shells  30 ,  31  has a flat portion  301  for covering on the outside surface of the sidewalls  222  of the mating portion  22 , a plurality of bent portions  302  bent extending from a bottom of the flat portion  301  and grounding tails  303  extending vertically through the recesses  211  of insulative housing  20  for electrically connecting to appropriate ground circuit traces on the printed circuit board. The flat portion  301  provides a plurality of bent tabs  304  in a top thereof for covering a top end of the sidewalls  222  of the mating portion  22  and latches  305  for engaging with the notches  221  of the sidewalls  222 . 
   In assembly, the terminals  26 ,  27  are inserted into corresponding terminal channels  241 ,  242  of the insulative housing  10  in a down-to-up direction. The first and the second shielding shells  30 ,  31  are assembled onto the insulative housing  20  in an up-to-down direction. The grounding tails  303  and the latches  305  of the shielding shells  30 ,  31  respectively engage with the recesses  211  and the notches  221  of the insulative housing  20  so that the shielding shells  30 ,  31  are firmly attached onto the insulative housing  20 . The mating portion  33  is entirely surrounded by the first and the second shielding shells  30 ,  31 . Therefore, the shielding shells  30 ,  31  can provide good EMI protection to the contact portions  261 ,  271  of the terminals  26 ,  27  located between. 
   When the receptacle connector  100  mates with the plug connector  200 , the mating portion  22  of the plug connector  200  is received in the receptacle  114  of the receptacle connector  100 , and the tongue plate  13  of the receptacle connector  100  is received in the slot  24  of the plug connector  200 . The contact portions  261 ,  271  of the terminals  26 ,  27  of the plug connector  200  respectively engage with the contact portions  151 ,  161  of the terminals  15 ,  16  of the receptacle connector  100 . The guiding posts  14  of the receptacle connector  100  are respectively received in the receiving rooms  28  of the plug connector  20 . During mating process, the engaging fingers  187  of the shielding shells  18 ,  19  of the receptacle connector  100  first abut against the metal plates  251  of the plug connector  200  to discharge Electro-Static charge accumulated in the connector, then the latches  186  of the shielding shells  18 ,  19  of the receptacle connector  100  engage with the flat portion  301  of the shielding shells  30 ,  31  of the plug connector  200  to form an electrical connection between the shielding shells  18 ,  19  of the receptacle connector  100  and the shielding shells  30 ,  31  of the plug connector  200 . The wings  182  of the shielding shell  18 ,  19  electrically connect with the metal plates  251 ,  252  disposed in the grooves  233 ,  232  of the plug connector  200  to achieve good shielding effect. 
   It is noted that the protrusions  115  on the outside surface of two side wall  111  are configured to be wedged for consideration of not only easy inspection of the soldering between the tail portions  152  and the printed circuit board thereunder while still maintaining the required strength thereof, but also resulting in a visional effect of a perpendicular relation between the protrusions  115  and the printed circuit board rather than an oblique manner performed by the remainder of the housing  10  with regard to the printed circuit board. 
   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.