Patent Publication Number: US-6217386-B1

Title: Connector with easily mating grounding contact

Description:
BACKGROUND OF THE INVENTION 
     1. The Field of the Present Invention 
     The present invention relates to a connector, and particularly to an electrical connector whose grounding contacts can easily be connected with shells for producing a good shielding effect. 
     2. Description of the Prior Art 
     A conventional connector shown in FIGS. 4-5 comprises an insulative housing  2 ′, a plurality of contacts  1 ′ and a plurality of shell  3 ′. A pair of crimps  14 ′ are formed on the distal end of the engaging portion  12 ′ of each contact  1 ′. Being cut from a metal sheet with the contact as a pair of tabs on opposite sides of the contact and then being oppositely bent toward each other produces the two crimps. In assembly each shell  3 ′ covers a protrusion  24 ′ of the housing  2 ′, two retention tabs  32 ′ of the shell  3 ′ being inserted into appropriate arc slots (not shown) in a front wall of the housing  2 ′. A distal end of each of the retention tab  32 ′ is exposed to a passage  22 ′ of the housing  2 ′ for contacting and interferingly fitting with the crimps  14 ′ of the contact  1 ′ (shown in FIG.  5 ). 
     In the prior art the two crimps  14 ′ are small controlled by the breadth of the engaging portion  12 ′ of the contact  1 ′ so that the resiliency is decreased and the rigidity is increased. The distal end of the retention tab  32 ′ forces two crimps  14 ′ open and is inserted therebetween. The contact and the shell firmly fit together but the interacting forces between them are so great that they can be damaged easily. Moreover, the retention forces required between the housing and the shell are great to prevent from separating from the housing during connection. An improved electrical connector is required to overcome the disadvantages of the prior art. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an electrical connector whose contacts can be easily connected with shells. 
     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. 
     A connector in accordance with the present invention comprises an insulative housing, a plurality of contacts and a plurality of shells. The housing has a bottom wall and a front wall forming a plurality of protrusions. A plurality of contact receiving passages is defined through the housing for receiving engaging portions of the contacts. A spring arm is formed on each engaging portion. The spring arm is large compared to the two crimps of the prior art, and thus has sufficient resiliency for resiliently engaging with a retention tab of the shell. The engaging force between the contact and the shell is relatively small and the retention force required between the housing and the shell is not great, so that assembling the contact with the shell while keeping the shell engaged with the housing is easily done. Guide faces are provided on a distal section of the spring arm and on the engaging portion of the contact to aid insertion of the retention tab therebetween. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of an electrical connector in accordance with the present invention; 
     FIG. 2 is a perspective view of an assembly of a contact and a shell of the present invention; 
     FIG. 3 is a sectional view of a contact and a shell of the present invention in assembly; 
     FIG. 4 is an exploded view of a conventional electrical connector; 
     FIG. 5 is a perspective view of the conventional contact and shell. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1-2, an electrical connector in accordance with a present invention comprises an insulative housing  2 , a plurality of contacts  1  and a plurality of shells  3 . 
     The housing  2  has a bottom wall  22  and a front wall  23 . Slots  221  are defined through the bottom wall  22  for orienting the contacts  1  in the housing  2 . A plurality of cylinder-shaped protrusions  24  is formed on the front wall  23 . Arc slots (not shown) are defined in the front wall  23  and on both sides of each protrusion  24 . A plurality of passages  21 ,  25  in communication with the arc slots (not shown) is defined through the housing  2 . 
     The contacts  1  are of three sizes, which slightly differ from each other in form but not in function. The three sizes aid in keeping the contact separated from each other in assembly in the housing  2 . Each contact comprises an extending portion  11  forming a solder tail  111  at a lower portion thereof and a base portion  12  at an opposite portion thereof, and an engaging portion  13  extending horizontally from the base portion  12 . The extending portion  11  of the smallest size contact  1  is L-shaped. The engaging portion  13  of each contact  1  has an S-shaped spring arm  131  punched from a plane of the contact and then bent forwardly in a longitudinal direction, whereby an opening  134  is formed and the spring arm  131  integrally extending from a front edge of said opening forwardly. Barbs  132  are formed on an opposite and a lower edge of the engaging portion  13  for interferingly fitting with an inner wall of the contact receiving passage  21  of the housing  2 . The engaging portion  13  has a clipping section  133  whose forward edge is bent outward thereby forming a guiding face  1331 . As shown in FIG. 3, another guiding face  1311  is formed on a distal edge of the spring arm  131 . 
     The shell  3  is a stamped, formed and deep drawn metal member. A stamping and forming process is used to produce a pair of integral retention tabs  31 , which form a plurality of barbs  311  on upper and lower edge thereof for interferingly fitting with an arc slot (not shown) of the housing  2 . A shielding portion  32  is produced through a deep drawn process. 
     In assembly each shell  3  covers a protrusion  24  of the housing  2 , the two retention tabs  31  being inserted into arc slots (not shown) on either side of the protrusion  24 . A distal end of each retention tab  31  extends into a contact receiving passage  21 ,  25  of the housing  2 . The extending portion  11  of each contact  1  is received in a slot  221 , the solder tail  111  extending through the bottom  22  for soldering to a printed circuit board. The engaging portion  13  is received in a corresponding passage  21 , the spring arm  131  interferingly fitting with the distal end of the retention tab as shown in FIG.  2 . 
     Referring to FIG. 3 during assembly the retention tab  31  is inserted between the two guide faces  1311  and  1331 , and is resiliently clipped and fixed therebetween. Because the forces of engagement are relatively small, The contact  1  and the shell  3  are not damaged during engagement, and retention of the shell  3  and the contact  1  in the housing  2  is not problematic, so assembly is facilitated. 
     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.