Abstract:
A card connector for connecting an expansion card to a circuit board and including a long insulating body with a central slot and a plurality of conductive terminals. The card connector also includes a metal casing with a covering function covering the insulating body. The metal casing prevents electromagnetic interference.

Description:
BACKGROUND OF THE INVENTION 
   (a) Field of the Invention 
   The present invention relates to connectors, and in particular to a card connector. 
   (b) Description of the Prior Art 
   In the connector industry, a card connector serves to connect an expansion card and a circuit board and usually includes a plastic seat and an ear buckle. The plastic seat has a plurality of conductive terminals and two sides have tower-shape portions. A receiving space is formed in a middle of the tower-shape portions so as to receive the ear buckle. Pivotal holes are formed at an interior of two side walls of the receiving space. The ear buckle is pivotally located in the pivotal hole. The ear buckle is capable of fixing firmly an expansion card to a card connector preventing signal interruption because of shaking of the expansion card. A retract mechanism is installed at the ear buckle so as to eject the expansion card from the card connector by rotating the ear buckle. However, accompanying with developing electric devices, electromagnetic interference caused by operating electric devices becomes more and more serious. Obviously, electromagnetic interference will seriously influence operation of the prior art of the card connector. 
   Therefore, it is necessary to develop a novel card connector for overcoming the above defects. 
   SUMMARY OF THE INVENTION 
   The primary objection of the present invention is to provide a card connector to assure a normal operation of the card connector. In order to achieve the object, the card connector connects an expansion card to a circuit board and has a long insulating body with a central slot and a plurality of conductive terminals. The card connector also has a metal casing with a covering function so as to cover the insulating body. 
   Compared to the prior arts, the card connector is capable of preventing electromagnetic interference so as to achieve a normal operation. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an assembled perspective view of the present invention. 
       FIG. 2  is an exploded perspective view of the present invention. 
       FIG. 3  is an illustration of the ejection device of the card connector of the present invention. 
       FIG. 4  is an illustration of the insulating body of the card connector of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   In order that those skilled in the art can further understand the present invention, a description is provided below. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims. 
     FIGS. 1 to 4  illustrate the card connector of the present invention. The card connector of the present invention is used to connect an expansion card (not shown) to a circuit board (not shown). The card connector includes a long insulating body  1 , a metal casing  2  covering he long insulating body  1 , a plurality of conductive terminals  3  and two ejection devices  4 . 
   The long insulating body  1  includes a pair of longer walls  10 . The walls  10  are located along the axial direction and have a central slot  11 . Two sides of the central slot  11  have two lines of terminal receiving holes  12  passing through the central slot  11 . The conductive terminals  3  are received in the terminal receiving holes  12 . The two ends of the long insulating body  1  have receiving portions  13  so as to receive the ejection devices  4 . The receiving portion  13  is formed by two shorter lateral walls  131  and an end wall  132 . A pivotal hole (not shown) is formed closely on the end wall  132  of an inner side of the receiving portion  13 . 
   The metal casing  2  is shaped into a sheet metal by pressing. The metal casing  2  includes a main body  20  and an extending retainer  21  formed by bending downwards two sides of the main body  20 . The main body  20  has a through hole  22  corresponding to the central slot  11 . Outwardly protruding protrusions  14  are installed on the insulating body  1 . The retainer  21  has a retainer groove  210  corresponding to each protrusion  14  so as to fix the metal casing  2  to the long insulating body. Alternatively, the long insulating body  1  has a downwards recess. Correspondingly, the receiving portion  13  has a matching fixing block so as to achieve the same purpose of fixing the metal casing  2  to the long insulating body  1 . 
   The ejection device  4  is pivotally connected to the receiving portion  13 . The ejection device  4  comprises a main body  41  and an ejection portion  42  formed by extending ends of the main body  41  so as to eject out a corresponding expansion card. The main body  41  has a long groove  43  passing through the main body  41 . The middle of the long groove  43  has a connecting arm  44 . Two sides of the main body  41  have projections  45  located close to the connecting arm  44 . When the ejection device  4  is received in the receiving portion  13  and rotated to a closed situation, the projection  45  buckles with an interior of the stop wall. A rotary shaft  46  is placed suitably under the projection  45  of the main body  41  so as to match up the pivotal hole on an inner side of the receiving portion  13 . The main body  41  has an operation portion  47  located on an end opposite the ejection portion  42  and the operation portion  47  inclines outwardly. The opposite end of the operation portion  47  extends inwards to form a projection portion  48 . The projection portion  48  is capable of buckling with the recess on the two sides of the expansion card so as to firmly fix the expansion card to the card connector, thereby achieving an electrical connection between the expansion card and a circuit board. Due to the metal casing  2 , the electric connection avoids electromagnetic interference. 
   The present invention is thus described, and it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.