Abstract:
A card connector includes an insulating housing ( 1 ), a number of contacts ( 2 ) and a shell ( 4 ). The insulating housing ( 1 ) defines a card receiving space ( 15 ) with a card insertion direction and comprises an engaging portion ( 114, 102 ). The contacts ( 2 ) are retained in the insulating housing ( 1 ) and exposed into the card receiving space ( 15 ). The shell ( 4 ) covered the insulating housing ( 1 ) comprises a resilient piece ( 411, 421 ) corresponding to the engaging portion ( 114, 102 ) of the insulating housing ( 1 ). The resilient piece ( 411, 421 ) of the shell ( 4 ) engages with the engaging portion ( 114, 102 ) of the insulating housing to urge the resilient piece to slightly distort elastically after the shell ( 4 ) is assembled to the insulating housing ( 1 ).

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is generally related to a card connector, and especially to a card connector which can be securely mounted on a Printed Circuit Board (PCB) to assure signal transmission. 
   2. Description of Related Art 
   Usually, consuming conducts, such as portable telephones, PDA (Personal Digital Assistance), digital cameras and the like, need electrical cards to enlarge and enhance functions thereof. Therefore, a plurality of card connectors adapted for receiving the corresponding cards are designed to accomplish requirements between the consuming products and the electrical cards. However, what is important is how to assure a secure signal transmission between the consuming products and the electrical cards with the aid of the card connectors. 
   U.S. Pat. No. 6,685,490 discloses a card connector which comprises an insulating housing, a plurality of contacts received in the insulating housing and a shell attaching to the insulating housing. The insulating housing is formed with protruding wedges and recesses on sidewalls thereof. The shell comprises mating holes and engaging pads corresponding to the protruding wedges and the recesses of the insulating housing. When the shell is assembled to the insulating housing, the protruding wedges of the insulating housing are received in the mating holes of the shell and the engaging pads of the shell are received in the recesses of the insulating housing. Then, the card connector is mounted on a PCB (Printed Circuit Board) in virtue of the shell soldered on the PCB. 
   However, cooperation of the insulating housing and the shell is not secure because the protruding wedges of the insulating housing and the engaging pads of the shell are commonly not tightly and securely received in the mating holes of the shell and the recesses of the housing, respectively. Therefore, with insertion times of a card inserting into the card connector increases, assembly between the shell and the insulating housing may become loose so that the electrical connection between the contacts and the PCB is affected. On the other hand, because assembly between the shell and the insulating housing is not tight enough, coplanarity is not assured when the card connector is mounted on the PCB in virtue of the shell soldering on the PCB. In such situation, it is bound to affect signal transmission between the card and the PCB. 
   Hence, an improved card connector is highly desired to overcome the aforementioned disadvantages of the prior art. 
   SUMMARY OF THE INVENTION 
   Accordingly, an object of the present invention is to provide a card connector which can be securely mounted on a Printed Circuit Board (PCB) to assure signal transmission. 
   To achieve the above abject, a card connector comprises an insulating housing, a number of contacts and a shell. The insulating housing defines a card receiving space with a card insertion direction and comprises an engaging portion. The contacts are retained in the insulating housing and are exposed into the card receiving space. The shell covered the insulating housing comprises at least a resilient piece corresponding to the engaging portion of the insulating housing. The resilient piece of the shell engages with the engaging portion of the insulating housing to urge the resilient piece to slightly distort elastically after the shell is assembled to the insulating housing. 
   Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of a preferred embodiment of the present invention with attached drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an assembled, perspective view of a card connector in accordance with the present invention; 
       FIG. 2  is an exploded, perspective view of the card connector of  FIG. 1 ; 
       FIG. 3  is a partially assembled, perspective view of the card connector of  FIG. 2 ; 
       FIG. 4  is an assembled, perspective view of the card connector of  FIG. 3 , with a shell not illustrated; and 
       FIG. 5  is an assembled, perspective view similar to  FIG. 1 , but taken from another aspect. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made in detail to the preferred embodiment of the present invention. 
   Referring to  FIGS. 1 to 5 , the card connector in accordance with the present invention comprises an insulating housing  1 , a plurality of contacts  2  received in the insulating housing  1 , an ejector  3  and a shell  4  covering the insulating housing  1 . 
   Referring to  FIGS. 1 and 2 , the insulating housing  1  is approximately frame configuration. The insulating housing  1  comprises a head portion  13 , a guiding arm  10  and a sidewall  11  both extending rearward from opposite lateral sides of the head portion  13 , which commonly define a card receiving space  15  with a card inserting opening  16  recessed inwardly from a rear face of the insulating housing  1  to communicate with the card receiving space  15 . The insulating housing  1  is provided with a transverse holding block  12  located adjacent to a rear end of the insulating housing  1  and exposed in the card receiving space  15  to connect the guiding arm  10  with the sidewall  11 . The holding block  12  comprises a plurality of receiving holes  120  arranged along a transverse direction perpendicular to a card insertion/ejection direction for accommodating the contacts  2  therein. 
   Referring to  FIGS. 1 to 3 , the head portion  13  comprises a vertical wall  14  protruding upwardly from a front end thereof and extending along the transverse direction to end up the card receiving space  15 . One end of the vertical wall  14  connects with the sidewall  11 . The sidewall  11  is formed with a cavity  112  for receiving the ejector  3 , a pinhole  1131 , both recessed downwardly from a top face thereof, and a protruding portion  1130  disposed on the top face thereof. The cavity  112 , the pinhole  1131  and the protruding portion  1130  are arranged approximately in alignment with one another along the card ejection direction. A column  140  protrudes rearward from the vertical wall  14  to expose into the cavity  112 . Furthermore, the card connector is formed with a plurality of L-shaped cuts  141  disposed on the front end of head portion  13  through the vertical wall  14 . 
   Each contact  2  is made of a metal sheet and comprises an intermediate portion  20  received in the receiving hole  120  of the holding block  12 , a contacting portion  21  bent upwardly from the intermediate portion  20  to exposed into the card receiving space  15  and a surface mount type soldering portion  22  downward and rearward extending from the intermediate portion  20  to the rear face of the insulating housing  1 . The width of the intermediate portion  20  is wider than that of the soldering portion  22 . 
   Referring to  FIGS. 2 to 4 , the ejector  3  for ejecting a card comprises a slider  30  disposed in the cavity  112  of the sidewall  11 , a spring  31 , a pin member  32  and a locking member  33 . The slider  30  can be moveable in the cavity  112  along the card insertion/ejection direction. An ejecting portion  303  protrudes into the card receiving space  15  from a top face of the slider  30  for ejecting the card and comprises a slanting ejecting face  300  formed on a rear end thereof. The slider  30  further comprises a hole  302  recessed rearward from a front face thereof to face to the column  140  of the vertical wall  14 . One end of the spring  31  is received in the hole  302  and opposite end is disposed around the column  140 . One end of the pin member  32  is moveably disposed in a hear-shaped slot  301  recessed downwardly from the top face of the slider  30 . The other end of the pin member  32  is securely locked in the pinhole  1131  of the sidewall  11 . One end of the locking member  33  locks in a bottom face of the slider  30  and opposite end protrudes into the card receiving space  15 . 
   The shell  4  is made of metal sheet and comprises a flat base portion  40  and a pair of opposite side portions  41 ,  42  extending downward from opposite lateral sides of the base portion  40 . The base portion  40  is provided with a pair of L-shaped mounting portions  43 ,  44  located in the corresponding cuts  141  of the insulating housing  1  and a holding portion  45  located adjacent to the side portion  41  along the transverse direction. The mounting portions  43 ,  44  and the holding portion  45  extend downward from a front end of the shell  4 . A T-shaped resilient portion  401  is disposed in the base portion  40  adjacent to a rear end of the base portion  40  and the side portion  41 . The holding portion  45  defines a rectangular hole  451  therein. The side portions  41 ,  42  are formed with a plurality of rectangular mating holes  412 ,  422  with different sizes and each defines a gap (not shown) to leave first and second resilient pieces  411 ,  421  extending from the base portion  40  in the gap of the shell  4 , respectively. The first resilient piece  411  locates between a pair of first mating holes  412  of the side portion  41  adjacent to a front end of the shell  4 . The second resilient piece  421  locates between the second mating holes  422  and faces to the first resilient piece  411 . A pair of mounting feet  413 ,  424  are disposed on the rear ends of the side portions  41 ,  42 , respectively. 
   Referring to  FIGS. 1 ,  3 ,  4  and  5 , the sidewall  11  of the insulating housing  1  further comprises a plurality of first wedges  115  and a first rectangular protrusion  114  served as an engaging portion, on outside of the sidewall  11  corresponding to the first mating holes  412  and the first resilient piece  411  of the shell  4 , respectively. Furthermore, bottom faces of the protrusion  114  and the housing  1  are coplanar. A protruding block  145  is disposed on a front end of the vertical wall  14  adjacent to the sidewall  11  corresponding to the rectangular hole  451  of the shell  4 . The guiding arm  10  also comprises a plurality of second wedges  103  and a second rectangular protrusion  102  on outside of the guiding arm  10  corresponding to the second mating holes  422  and the second resilient piece  421 , respectively. The second rectangular protrusion  102  is arranged in alignment with the first rectangular protrusion  114  along the transverse direction and bottom faces of the second protrusion  102  and the housing  1  are also coplanar. The shell  4  is formed with a cutout  402  in the rear end thereof adjacent to the soldering foot  413  corresponding to the protruding portion  1130 . 
   Referring to  FIGS. 1 to 5 , when the shell  4  is assembled to the insulating housing  1 , the resilient portion  401  presses downward against the pin member  32  in the hear-shaped slot  301  of the ejector  3 . The first wedges  115 , the second wedges  103 , the protruding block  145  and the protruding portion  1130  of the insulating housing  1  are respectively received in the first mating holes  412 , the second mating holes  422 , the rectangular hole  451  and the cutout  402  of the shell  4  to hold the shell  4  to cover the insulating housing  1 . At the same time, in this embodiment, the first and second resilient pieces  411 ,  421  of the shell  4  engage tightly with the first and second rectangular protrusions  114 ,  102  of the insulating housing  1  respectively to urge the resilient pieces  411 ,  421  to produce elastic distortion because the height of the resilient piece  411  or  421  plus corresponding rectangular protrusion  114  or  102  is higher than that of the insulating housing  1 . Certainly, it is not necessary that the height of the resilient piece  411  or  421  plus corresponding rectangular protrusion  114  or  102  is higher than that of the insulating housing  1  on condition that it can urge the resilient piece  411  or  421  to produce elastic distortion when the resilient piece  411  or  421  collides with the corresponding protrusion  114  or  102  respectively after the shell  4  assembles to the insulating housing  1 . For example, distance between upper faces of the protrusions  114  or  102  and the insulating housing  1  is shorter than the height of the resilient piece  411  or  421 . Therefore, because of the elastic distortion of the resilient pieces  411 ,  421 , the shell  4  can mount tightly on the insulating housing  1 . 
   On the other hand, because of the elastic distortion of the resilient pieces  411 ,  421  after the shell  4  assembled to the insulating housing  1 , the shell  4  mount tightly on the insulating housing  1 . In this situation, the mounting portions  43 ,  44  and the mounting feet  413 ,  424  of the shell  4  have secure coplanarity when they are soldered on the PCB. Therefore, the card connector can be soldered on the PCB securely with more rigid coplanarity. 
   While a preferred embodiment in accordance with the present invention has been shown and described, equivalent modifications and changes known to persons skilled in the art according to the spirit of the present invention are considered within the scope of the present invention as described in the appended claims.