Patent Publication Number: US-2005130510-A1

Title: Electrical card connector

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention generally relates to electrical card connectors used in electronic appliances such as a palmtop computer and a cellular phone, and more particularly to a Subscriber Identity Module (SIM) card connector.  
      2. Description of the Related Art  
      As is well-known, chip or smart cards are used for various purposes, for instance as prepaid telephone cards. Such a telephone card allows the purchaser to insert the card into a public telephone and then make telephone calls equivalent to the amount of money paid for said telephone card. Chip cards are also used to identify members of, for instance, a health organization and so on. SIM cards derive their name form the words “subscriber identity module”. SIM cards are frequently used in so-called cell phones, for instance to identify a subscriber of the respective telephone company.  
      As the size of such pocket-size cellular phones decreases, there is a constant demand to make electrical components in the cellular phones smaller and lighter in weight. U.S. Pat. No. 6,000,969 issued to Reichardt et al. on Dec. 14, 1999 discloses a card connector comprising an insulating body and a plurality of conductive contacts received in the housing. Each contact has contact end projecting beyond the insulating body, a connection end and a guide portion extending between the connection end and the contact end. The connection ends of the contacts resting under prestress on a bottom surface of the insulating for being soldered to a circuit board.  
      However, the Reichardt contacts are mounted on the insulating body only by the connection ends abutting against corresponding portions of the housing, which increase the difficulty of orientation during assembling the card connector to the circuit board. Moreover, it is difficult to accurately position the contacts in the housing since the guiding portions of the contacts are received in the insulating body without retention, thus rendering contact area of each contact in different surfaces. Therefore, electrically connections between the contacts and a memory card are unreliable.  
      Hence, an electrical card connector with reliable contacts is needed to overcome the foregoing shortcomings.  
     BRIEF SUMMARY OF THE INVENTION  
      A main object of the present invention is to provide an electrical card connector having reliable conductive contacts.  
      An electrical card connector is mounted on a circuit board for mating with a memory card. The card connector includes an insulative housing and a number of conductive contacts fixed in the hosing. The housing has an upper and bottom faces. A number of recesses and cavities are defined the upper face and communicating with each other in the bottom face. Each recess has a fixing wall in a lower portion. The contacts are received in corresponding cavities and each includes a body portion, a resilient deflectable contact arm with one end connecting with the body portion, a first fixing portion extending upwardly through a corresponding recess from a first end of the body portion and bent to abut against the fixing wall, and a connection end extending from a second end of the body portion adapted to electrically contact the circuit board. The contact arm has a contact portion projecting through the corresponding cavity and above the upper face for engaging with the memory card.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which:  
       FIG. 1  is a perspective view of an electrical card connector according to the present invention;  
       FIG. 2  is another perspective view of  FIG. 1 , taken from bottom aspect;  
       FIG. 3  is an exploded view of  FIG. 1 , wherein conductive contacts are in their former state;  
       FIG. 4  is another perspective view of an insulative housing shown in  FIG. 3 , taken from bottom aspect;  
       FIG. 5  is a cross-sectional view of the insulative housing taken along line  5 - 5  of  FIG. 3 ;  
       FIG. 6  is a cross-sectional view of the electrical card connector taken along line  6 - 6  of  FIG. 1 , but showing the contacts in their former state; and  
       FIG. 7  is anther cross-sectional view of  FIG. 6 , but showing the contacts in their final state. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to  FIGS. 1, 2  and  3 , an electrical card connector  100  of the present invention adapted for installing a memory card, such as a SIM card therein is provided for mounting on a printed circuit board (PCB, not shown) of an electronic appliance, such as a cellular phone. The electrical card connector  100  comprises an insulative housing  1  and a plurality of conductive contacts  2  received in the housing  1 . The conductive contacts  2  are arranged in two rows, with the contacts  2  in one row being turned 180 degrees about a vertical axis with respect to the contacts  2  of the other row.  
      As best shown in  FIG. 3  in conjunction with  FIGS. 1 and 2 , each conductive contact  2  is stamped from a metal sheet and comprises a body portion (not labeled), a resilient deflectable contact arm  22  stamped upwardly from the body portion, a first fixing portion  23 , a second fixing portion  24  and a connection end  25 . The body portion is a substantially rectangular frame and includes a pair of spaced beams  21  joined together at both their front and rear ends. The contact arm  22  lies between the beams  21  and comprises a base portion  221  extending rearwardly and upwardly from the front end of the body portion, and a convexly curved contact portion  222  in a free end thereof for engaging with a memory card pad (not shown) of the memory card. The first fixing portion  23  extends upwardly from the front end of the body portion, and the second fixing portion  24  extends downwardly from the rear end of body portion. The connection end  25  is positioned in a middle portion of the second fixing portion  23  and bends outwardly to be soldered on the PCB.  
      Referring to  FIGS. 3, 4  and  5 , the insulative housing  1  is substantially lower profile rectangular shaped and has an upper face  11  and a bottom face  15 . The housing  1  comprises two rows of longitudinally-extending slots  12  in the upper face  11 , two rows of upwardly-opening recesses  13  in a middle portion of the upper face  11 , and a plurality of downwardly-opening cavities  14  in the bottom face  15  communicating with corresponding slots  12  and recesses  13 . Each recess  13  provides a fixing wall  131  in a lower portion thereof for supporting the front fixing portion  23  of the contact  2 . Each cavity  14  provides an L-shaped stepped supporting portion  141  for supporting the beams  21  of the contact  2 , a groove  142  in the bottom face  15  for receiving the second fixing portion  24 , and a cutout  143  proximate the groove  142  and communicating with the groove  142  for accommodating the connection end  25  of the contact  2 .  
      Referring to  FIGS. 6 and 7  in conjunction with  FIGS. 1 and 2 , in assembly, the conductive contacts  2  are embedded in the housing  1  from the cavities  14 . The beams  21  of the contacts  2  are positioned on the supporting portions  141  of the housing  1 . The convexly curved contact portion  222  of the contact arm  22  of each contact  2  upwardly projects beyond a corresponding slot  12  of the housing  1  for engaging with the memory card. The second fixing portion  24  of each contact  2  lies in the groove  142  of the housing  1 . The connection end  25  of each contact  2  is held in the cutout  143  of the housing  1 . The first fixing portion  23  of each contact  2  extends beyond the recess  13  and is bent downwardly to abut against a top surface of the fixing wall  131 . Therefore, the contacts  2  are securely fixed in the housing  1 . It should be noted that a top surface of the bent first fixing portion  23  is no higher than the upper face  11  of the housing  1 .  
      It is to be understood, however, that even though numerous, characteristics and advantages of the present invention have been set fourth in the foregoing description, together with details of the structure and function of the invention, the disclosed 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.