Patent Publication Number: US-6910900-B2

Title: Grounded electrical connector

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Relevant subject matter is disclosed in a pending U.S. patent application Ser. No. 10/452,159, filed on May 30, 2003 and entitled “GROUNDED ELECTRICAL CONNECTOR”, which is invented by the same inventor as this patent application and assigned to the same assignee with this application. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an electrical connector, and particularly to a board-to-board connector with reliable grounding means. 
   2. Description of Related Art 
   Board-to-Board connector assembly generally includes a plug and a receptacle connectors respectively mounted on two parallelly spaced printed circuit boards (PCB) and mated with each other for mechanical and electrical interconnection therebetween, whereby the corresponding printed circuit boards can be electrically connected with each other for signal transmission. 
   A conventional board-to-board connector assembly can be referred to U.S. Pat. No. 5,915,976 which discloses a plug and a corresponding receptacle connector. The receptacle connector includes a housing, a number of contacts disposed in inner opposite sides of the insulative housing, and a pair of shielding plates positioned on outer opposite sides of the insulative housing. Each shielding plate has a number of hooks extending from a bottom end thereof. The hooks extend into the insulative housing and contact with predetermined contacts for forming a grounding path to filter noises and EMI (electromagnetic interference). 
   With high speed and high frequency signals transmitting in the board-to-board connector assembly, contacts of the connector assembly generate much more quantity of heat comparing with low speed and low frequency signals transmission. However, there is no enough room inside the mated connector assembly for meeting the requirements of heat dissipation. Thus, an appropriate approach is to increase the height of the receptacle connector to provide additional room. Accordingly, the shielding plate and the contacts has to be heightened to match the heightened receptacle connector. Whereas, such heightened shielding plate and contacts are readily warped during assembly and transportation of the connector, which will cause the contact between the hooks of the shielding plate and the predetermined contacts unstable or even break away, thereby degrading the effect of filtering EMI and resulting in poor transmission of signals. 
   Hence, an improved board-to-board connector is desired to overcome the disadvantage of the prior art. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to provide an electrical connector having a stable and reliable grounding means for filtering noises and EMI. 
   To achieve the above object, an electrical connector comprises a dielectric housing, a plurality of signal terminals and grounding terminals, a shielding member and a grounding member. The dielectric housing comprises a mating surface, a mounting surface, a pair of side walls extending between the mating surface and the mounting surface and a mating space in the mating face between the side walls. Each side wall defines a plurality of passageways in an inner face thereof and a plurality of channels in the mounting face. The signal and grounding terminals are received in corresponding passageways, respectively. The shielding member is attached to outer faces of the side walls. Each grounding member comprises an intermediate portion and three spaced beams extending from one side of the intermediate portion along a same direction. A middle one of the three beams is snugly retained in corresponding channel. The other two beams electrically and mechanically presses the grounding terminal and the shield plate against the side walls, respectively. 
   Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view of an electrical connector in accordance with the present invention; 
       FIG. 2  is an assembled perspective view of the connector shown in  FIG. 1 ; 
       FIG. 3  is a cross-sectional view of the connector taken along line  3 — 3  of  FIG. 2 ; and 
       FIG. 4  is a cross-sectional view of the connector taken along line  4 — 4  of  FIG. 2 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 1 and 2 , an electrical connector  1  in accordance with the present invention comprises an elongate dielectric housing  10 , a plurality of signal terminals  20  and grounding terminals  25  received in the dielectric housing  10 , respectively, a shielding member  40  attached to the dielectric housing  10  and a plurality of grounding members  30 . 
   Referring to  FIGS. 1 and 3 , the dielectric housing  10  has a mating surface  11  and a mounting surface  12  opposite to the mating surface  11 . Laterally spaced opposite side walls  13  and longitudinally spaced opposite end walls  14  extend between the mating surface  11  and the mounting surface  12 , respectively. The dielectric housing  10  defines a mating space  16  in the mating surface  11  between the side walls  13  and a cavity  17  in the mounting surface  12  between the side walls  13 . A clapboard  15  is formed between the mating space  16  and the cavity  17  and interconnects with the side walls  13  and the end walls  14 . Each side wall  13  defines a plurality of passageways  131  in an inner face  130  thereof. Each passageway  131  communicates with the mating space  16  and the cavity  17  and passes through a joint of the side wall  13  and the clapboard  15 . The side wall  13  has a plurality of pairs of protrusions  134 , a plurality of cutouts  135  alternatively arranged with the pair of protrusions  134  along a lengthwise direction thereof and a plurality of recesses  136  located below the protrusions  134  and the cutouts  135  on an outer face  133  thereof. As best shown in  FIGS. 1 and 4 , each side wall defines a plurality of notches  137  aligned with corresponding predetermined passageways  131  in the mounting surface  12  and a plurality of channels  138  recessed toward the mating surface  11  from corresponding notches  137 . 
   Referring to  FIGS. 3 and 4 , each signal terminal  20  is received in corresponding passageways  131  and comprises a contact portion  21  exposed into the mating space  16 , a retaining portion  22  retained in the passageway  131  and exposed into the cavity  17  and a solder portion  23  perpendicularly extending from the retaining portion  22  for being surface mounted onto a printed circuit board (not shown). Each grounding terminal  25  is received in predetermined passageways  131  and comprises a contact portion  26  exposed into the mating space  16  and a tail portion  27  exposed into the cavity  17 . 
   The shield member  40  comprises a pair of shield plates respectively attached to the outer faces  133  of the side walls  13  for shielding purpose. Each shield plate comprises a plurality of retention blades  43  extending from an upper edge thereof for cooperating with corresponding pairs of protrusions  134  of the side wall  13  and a plurality of spring tangs  45  stamped therefrom for being received in a corresponding recess  136  to secure the shield plate to the dielectric housing  10 . The shield plate  40  further comprises a plurality of grounding tangs  44  each positioned between every adjacent two retention blades  43  for facing to a corresponding cutout  135  which is adapted to receive a grounding contact of a complementary connector (not shown). 
   Referring to  FIG. 4 , each grounding member  30  is stamped from a metal sheet and comprises an approximately horizontal intermediate portion  31 , three substantially parallel beams perpendicularly extending from one side of the intermediate portion along a same direction and spaced from one another, and a soldering portion  32  horizontally extending from the intermediate portion  31  for being surface mounted onto the printed circuit board. One of the three beams electrically contacting with the shield plate is a shield contact portion  33 . The other of the three beams electrically contacting with the grounding terminal  30  is a terminals contact portion  34 . Another of the three beams between the terminal contact portion and the shield contact portion is a retaining portion  35 . The grounding member  30  is assembled to the housing  10  with the intermediate portion  31  received in the notch  137  and the retaining portion  35  retained in the channel  138 . The shield contact portion  33  tightly presses a bottom edge of the shield plate toward the retaining portion  35  and the terminal contact portion  34  tightly presses the tail portion  27  of the grounding terminal  25  toward the retaining portion  35 , thereby preventing the shield plate and the grounding terminal  30  from warpage and securing the shield plate to the dielectric housing  10 . At the same time, an efficient protection of EMI is established reliably. 
   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.