Abstract:
A cable connector assembly ( 100 ) includes a printed circuit board ( 2 ) having a number of signal and ground pads ( 25, 26 ) alternatively arranged at opposite front and rear ends thereof, a wire organizer ( 3 ) defining a number of through holes ( 30 ), a unitary grounding member ( 6 ) assembled to the wire organizer and including a number of grounding plates ( 62 ) integrally formed therewith to electrically connect with the ground pads of the printed circuit board, and a number of wires ( 4 ) protruding through the through holes of the wire organizer. Each wire includes at least one signal conductor ( 40 ) soldered with the signal pad of the printed circuit board, an insulator ( 41 ) enclosing the at least one signal conductor and a ground conductor ( 43 ) electrically connecting with the grounding member to form ground path with the printed circuit board.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a cable connector assembly, and more particularly to a cable connector assembly for high-speed signal transmission. 
     2. Description of Related Art 
     For high-speed signal transmission electrical connectors, EMI and wire management are two most significant problems to be solved since such electrical connector usually has a large number of wires to transmit signals which need to be managed. Infiniband connector is a kind of high-speed signal transmission connector which comprises an insulative housing, a plurality of signal and ground terminals retained in the insulative housing, a spacer assembled to the housing and the terminals, a plurality of wires each comprising a signal differential pair transmitting positive and negative signals and a grounding conductor. The wires are managed by the spacer with the signal differential pairs and the grounding conductors respectively electrically connecting with the signal and ground terminals. Additionally, for depressing EMI, a grounding member is adopted to electrically connect with the ground terminals and the grounding conductors. 
     Such features are disclosed in U.S. Pat. Nos. 6,685,501, 6,726,503, 6,764,342, 6,869,308, and 6,739,904. As for U.S. Pat. Nos. 6,685,501, 6,869,308 and 6,739,904, each spacer disclosed therein is a whole piece or a pair of upper and lower halves defines a plurality of aligning holes to permit the penetration of wires for aligning the wires. Each spacer is assembled with a large number of grounding plates each soldered to corresponding grounding conductors of the wires and ground terminal to depress EMI in signal transmission. However, the number of the grounding plates is large which is costly and assembling the so many grounding plates to the spacer is time consuming and also costly. 
     U.S. Pat. No. 6,726,503 discloses an Infiniband type connector with a spacer having upper and lower halves assembled together to align wires and engaging with tail portions of ground terminals with grounding conductors electrically connecting with the tail portions of the ground terminals. U.S. Pat. No. 6,764,342 discloses a whole-piece spacer aligning wires and assembled with a pair of grounding plates and short arms of ground terminals with the grounding plates directly electrically connecting with grounding conductors of the wires and the short arms of the ground terminals to form electrical connection between the ground terminals and the grounding conductors of the wires. However, the ground terminals of these two connectors all directly connect the grounding plates or the grounding conductors of the wires. In some circumstances, a printed circuit board is needed to realize the electrical connection between terminals and wires. The spacers and the grounding plates are not suitable for above circumstance. Therefore, a cable connector with improved wire organizer and grounding plate is desired to be developed to address above problems. 
     BRIEF SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide a cable connector assembly with improved grounding member to achieve EMI depression and low cost. 
     In order to achieve the above-mentioned object, a cable connector assembly in accordance with the present invention comprises a printed circuit board having a plurality of signal and ground pads alternatively arranged at opposite front and rear ends thereof, a wire organizer defining a plurality of through holes, a unitary grounding member assembled to the wire organizer and comprising a plurality of grounding plates integrally formed therewith to electrically connect with the ground pads of the printed circuit board, and a plurality of wires protruding through the through holes of the wire organizer. Each wire comprises at least one signal conductor soldered with the signal pad of the printed circuit board, an insulator enclosing the at least one signal conductor and a ground conductor electrically connecting with the grounding member to form ground path with the printed circuit board. 
     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 an exploded, perspective view of a cable connector assembly in accordance with the preferred embodiment of the present invention; 
         FIG. 2  is a view similar to  FIG. 1 , but viewed from a different aspect; 
         FIG. 3  is a partially assembled view of  FIG. 1 ; and 
         FIG. 4  is an assembled, perspective view of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made to the drawing figures to describe the present invention in detail. 
     Please refer to  FIGS. 1-2 , a cable connector assembly  100  in accordance with the preferred embodiment of the present invention comprises a printed circuit board (PCB)  2 , a pair of metal grounding members  6  (only one is shown) electrically connecting with the PCB  2  and wires  4 , a wire organizer  3  aligning the wires  4  and engagingly receiving the grounding members  6 , the wires  4  electrically connecting with the grounding members  6  and the PCB  2  at the same time, an inner mold  5  molded with the wires  4 , and a die-cast casing (not shown) enclosing all the members mentioned above therein with the wires  4  exiting from rear end of the casing and the mating interface accessible from front end of the casing. 
     The PCB  2  is a flat board, and comprises opposite front and rear ends  21 ,  22  and opposite upper and lower surfaces  23 ,  24 . A plurality of first and second conductive pads  25 ,  26  are formed at front and rear ends  21 ,  22  of the upper and lower surfaces  23 ,  24 . The first and second conductive pads  25 ,  26  are in pairs along front-to-rear direction and each pair  25 ,  26  connects to each other by a conductive trace  20 . Each set of the first and second conductive pads  25 ,  26  consist of four sets of signal differential pairs  250 ,  260  and five ground pads  252 ,  262  alternatively arranged with the signal differential pairs  250 ,  260  for assuring signal transmission effect. 
     The wire organizer  3  made from insulative material is of a rectangular block. The wire organizer  3  defines upper and lower rows of elliptic-shape through holes  30  spaced arranged along transverse direction. The inner periphery of each through hole  30  is same as outer periphery of each wire  4 . The through holes  30  of the upper row are not aligned with the through holes  30  of the lower row in up-to-down direction. That is, each through hole  30  of the upper row is substantially located between a pair of through holes  30  of the lower row. A pair of openings  31  are respectively recessed downwardly and upwardly from upper and lower surfaces of the body portion  30  and respectively communicate with the through holes  300  of the upper row and the through holes  30  of the lower row. 
     Each grounding member  6  comprises a fitting portion  61  interferentially received in the openings  31  of the wire organizer  3 , and a plurality of grounding plates  62  extending forwardly from lower/top edge of the fitting portion  61 . The lower/top edge of each fitting portion  61  defines a plurality of semi-elliptical receiving spaces  610  between adjacent two grounding plates  62  for receiving the wires  4 . Each grounding plate  62  is located in a vertical plane and substantially of L-shape. The grounding plate  62  comprises a rear wider stop section  621  connecting with the fitting portion  61  and a narrower soldering section  622  extending from upper/lower part of the stop section  621  of upper/lower row. A slit  620  extends upwardly/downwardly from the joint location of the stop section  621  and the soldering section  622  for receiving excessive solder when soldering the grounding members  6  with the ground pads  262  of the PCB  2 . The structure of the fitting portion  61  of the grounding member  6  is corresponding to outer periphery of the opening  31 . The fitting portion  61  comprises a U-shape sandwiching section  611  sandwiching a vertical front edge of the opening  31  and a flat pressing section  612  extending rearwardly from rear edge of the sandwiching section  611  to press on the wires  4  received in the through holes  30 . A vertical flange  6121  extends upwardly a certain distance from rear edge of the pressing section  612  for preventing warp of the pressing section  612  from the opening  31 . A plurality of slits  6111  are defined in the sandwiching section  611 . 
     The wires  4  are divided into upper and lower groups (only one row is shown) corresponding to the through holes  30  of the wire organizer  3 , that is, each wire  4  of the upper group is located in the middle of the two adjacent wires  4  of the lower group viewed from up-to-down direction. Such arrangement helps to reduce cross talk in signal transmission. Each wire  4  comprises a pair of signal conductors  40  respectively transmitting positive and negative signals, a pair of insulators  41  respectively enclosing corresponding signal conductors  40 , a pair of conductive layers  44  surrounding the insulators  41 , a ground conductor  43  disposed between the pair of signal conductors  40  and electrically contacting the conductive layers  44 , and an outer jacket  42  enclosing the conductor layers  44  and the ground conductor  43  therein. The front end of the wire  4  is partially stripped to expose the pair of signal conductors  40 , the front ends of the pair of insulators  41 , the pair of conductive layers  44  and the ground conductor  43  along front-to-back direction. The ground conductor  43  exposed out of the outer jacket  42  is longer than the signal conductors  40  exposed out of the outer jacket  42  for being of U-shape to locate above/below the pair of signal conductors  40  after assembling to the wire organizer  3 . 
     When assembly, the inner mold  5  is firstly molded with the wires  4  to hold the wires  4  together. Then, the wires  4  respectively protrude through the through holes  30  of the wire organizer  3  to fill up the through holes  30  with upper and lower parts of the outer jackets  42  thereof exposed in the openings  30 . Then the grounding member  6  is assembled to the wire organizer  3  and the wires  4  with the fitting portion  61  interferentially received in the opening  30  as described above and each grounding plate  62  locating between two adjacent wires  4 . The pressing section  612  is pushed to exert a downward/upward force to the wires  4  to press the exposed portions of the wires  4  for adjusting the configurations of the wires  4  to fit in the through holes  30  well. There are four round positioning holes  6120  in the pressing section  612  corresponding to the position of the wires  4 . Glue or other may spread to the positioning holes  6120  to position the wires to the grounding member  6 . Further, Glue made from Epoxy Bong may be spread to the openings  31  of the wire organizer  3  to retain the wire organizer  3  with the grounding plate  6 . After such assembly, the front ends of the signal conductors  40  substantially flush with the front edges of the grounding plates  62 . Then, the wires  4  and the grounding member  6  are assembled to the PCB  2  together with the stop portions  621  abutting against the rear end  22  of the PCB  2 . The soldering portions  622  of the grounding plates  62  and the signal conductors  40  are respectively soldered to the ground pads  262  and the signal differential pairs  260  of the second conductive pads  26  to form electrical connection therebetween. The ground conductors  43  are formed into U-shape and soldered to side surfaces of the grounding plates  62 . Thus, signal transmission paths and grounding paths are established. In alternative embodiment, the ground conductors  43  also can be pressed through the slits  6111  into conductor-receiving slots  6112  to electrically connect with the grounding member  6  to form ground paths with the PCB  2 . When mating with a complementary connector, the first conductive pads  25  of the PCB  2  may directly electrically connect with terminals of the complementary connector, or soldered with contacts (not shown) assembled into an insulative housing (not shown) of the cable connector assembly of the present invention. 
     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.