Abstract:
In a push-push type card connector in which a contact held by an insulator, an eject lever is coupled to the insulator to be movable in ejecting and inserting directions of a card and is continuously urged by a spring in the ejecting direction. The insulator has a pair of frame portions which are for guiding the card in the ejecting and the inserting directions. The contact is for coming in contact with the card inserted between the frame portions in the inserting direction. The eject lever has a guide portion slidable along one of the frame portions and an engaging portion for being engaged with the card in the ejecting direction.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a push-push type card connector capable of inserting/ejecting a card into/from the connector by repeating a pushing operation of the card. 
     A card connector of the type is disclosed, for example, in Japanese Unexamined Patent Publication (A) No. H10-312854. Hereinafter, the card connector disclosed in the above-mentioned publication will be summarized. The card connector comprises a body, a frame fixed to the body, a slider for sliding with respect to the frame upon insertion and ejection of the card and for receiving the card to be mounted thereon, a cam mechanism formed on the slider, and a detection switch formed on the body to detect a state where the card is fitted into the connector. The cam mechanism serves to lock the state where the card is fitted into the connector. The detection switch is provided with a pin member movably attached thereto so as to open and close the detection switch and to lock the cam mechanism. When the slider is inserted into the connector and the card is fitted into the connector, the pin member is engaged with a branching portion of the cam mechanism to lock the slider and brings a movable armature of the detection switch into contact with a fixed armature. 
     In the above-mentioned conventional card connector, the pin member for locking the slider and its attachment structure are complicated. In addition, a large number of components are necessary. As a result, it is difficult to miniaturize the connector. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of this invention to provide a push-push type card connector which is simple in structure and small in number of components. 
     Other objects of the present invention will become clear as the description proceeds. 
     According to the present invention, there is provided a push-push type card connector which comprises an insulator having a pair of frame portions which are for guiding a card in an ejecting direction thereof and an inserting direction opposite to the ejecting direction, a contact held by the insulator for coming in contact with the card inserted between the frame portions in the inserting direction, an eject lever coupled to the insulator and movable in the ejecting and the inserting directions, and a spring continuously urging the eject lever in the ejecting direction. The eject lever comprises a guide portion slidable along the one of the frame portions and an engaging portion connected to the guide portion for being engaged with the card in the ejecting direction. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a perspective view of a push-push type card connector according to an embodiment of this invention; 
     FIG. 2 is an exploded perspective view of the connector in FIG. 1; 
     FIG. 3 is a schematic view showing a shape of a cam groove of a cam mechanism in the connector in FIGS. 1 and 2; 
     FIGS. 4A through 4E are perspective views showing a series of steps upon insertion and ejection of a card into and from the connector in FIG. 1; and 
     FIGS. 5A through 5E are views for describing a movement of the cam mechanism in FIGS. 1 and 2. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2, description will be made as regards an overall structure of a push-push type card connector according to an embodiment of this invention. 
     The connector is depicted by a reference numeral  1  and includes an insulator  2 , a plurality of contacts  3  fixed to the insulator  2 , an eject lever  4  attached to a frame portion  2   a  of the insulator  2 , a compression coil spring  5  continuously urging the eject lever  4  in an ejecting direction A 1 , and a cam follower  6  adapted to be guided along a cam groove  4   c  made or formed in the eject lever  4 . The cam groove  4   c  is generally heart-shaped and will be referred to as a heart cum. 
     A card  11  is inserted into the connector  1  in an inserting direction A 2  opposite to the ejecting direction A 1  and is ejected from the connector  11  in the ejecting direction A 1 . The connector  1  is entirely covered with a rectangular cover (not shown). 
     The insulator  2  has a generally rectangular shape and is made from a synthetic resin material. The insulator  2  is provided with U-shaped frame portions  2   a ,  2   b , and  2   c  formed on three sides thereof, respectively. Each of contacts  3  has a convex-curved contact point  3   a  at one end and a flat contact point  3   b  at the other end. The convex-curved contact point  3   a  protrudes into an area to which the card  11  is inserted. 
     The eject lever  4  has a generally L shape and is made from a metal material. The eject lever  4  has a guide portion  4   a  and a right angle bending portion  4   b . The guide portion  4   a  is provided with a cam groove  4   c  formed on one surface thereof. The right-angle bending portion  4   b  has a card contacting portion  4   d  for receiving a forward end of the card  11  to be brought into contact therewith. The guide portion  4   a  of the eject lever  4  is slidably received in a groove (not shown) having a U-shaped section and formed in the frame portion  2   a . The compression coil spring  5  is inserted into a groove  4   e  formed on one surface of the guide portion  4   a . The compression coil spring  5  has one end brought into contact with the eject lever  4  and the other end brought into contact with an inner surface of the frame portion  2   c . Accordingly, the eject lever  4  is continuously urged by the compression coil spring  5  in the ejecting direction in which the card  11  is ejected from the connector  1 . 
     The cam follower  6  is formed into a lever-like shape and disposed in a notch  2   d  formed on the outside of the frame portion  2   a  to be rotatable over a predetermined angle. The cam follower  6  has a hole  6   a  formed at its base portion and fitted over a shaft  2   e  formed on the frame portion  2   a . In other words, the cam follower  6  is pivoted at its base portion by the frame portion  2   a . The cam follower  6  has a guide pin  6   b  which is formed by bending at its tip portion and penetrates a hole (not shown) formed on the frame portion  2   a  to be engaged with the cam groove  4   c . A combination of the heart cum or the cam groove  4   c  and the cam follower  6  will be referred to as a position control arrangement for controlling a position of the eject lever  4  in the ejecting and the inserting directions. 
     Referring to FIG. 3 in addition, description will be made of the cam groove  4   c  in detail. The cam groove  4   c  has a start point {circle around ( 1 )} where the guide pin  6   b  of the cam follower  6  starts to move, a guide portion {circle around ( 2 )} inclined with respect to a sliding direction of the eject lever  4 , a depressed portion {circle around ( 3 )} following the guide portion, a guide portion {circle around ( 4 )} parallel to the sliding direction of the eject lever  4 , namely, the ejecting direction A 1  and the inserting direction A 2  of the card  11 , and a terminal point {circle around ( 5 )} where the guide pin  6   b  finally arrives, which is identical with the start point {circle around ( 1 )}. In a free state, the guide pin  6   b  is preliminarily urged by elasticity of the cam follower  6  leftward in FIG. 3, namely, towards the guide portion {circle around ( 2 )} inclined as mentioned above. 
     Further referring to FIGS. 4A through 4E and  5 A through  5 E, description will be made of insertion and ejection of the card  11  into and from the connector  1 . FIGS. 4A through 4E and FIG. 5A through 5E are in one-to-one correspondence to each other. 
     FIG. 4A shows the free state where the card  11  is partially inserted into the connector  1 . In the free state, the guide pin  6   b  of the cam follower  6  is positioned at the start point ({circle around ( 1 )} in FIG. 3) of the cam groove  4   c , as shown in FIG.  5 A. 
     When the card  11  is pushed inward into the connector  1 , the forward end of the card  11  is brought into contact with the card contacting portion  4   d  of the eject lever  4 . Thereafter, the card  11  and the eject lever  4  are integrally slide towards the interior of the connector  1  against compression force of the compression coil spring  5 . This sliding state is shown in FIG.  4 B. In the sliding state shown in FIG. 4B, the guide pin  6   b  is positioned at the inclined guide portion ({circle around ( 2 )} in FIG. 3) of the cam groove  4   c , as shown in FIG.  5 B. 
     Subsequently, the card  11  is pushed over a maximum stroke and, thereafter, the pushing operation is stopped. In this event, the card  11  and the eject lever  4  are slightly returned by restoring force of the compression coil spring  5  to be put in a fitting state shown in FIG.  4 C. In the fitting state of FIG. 4C, a plurality of pads (not shown) of the card  11  are kept in contact with the convex-curved contact points of the contacts  3 , respectively. At the same time, the guide pin  6  is positioned at the depressed portion ({circle around ( 3 )} in FIG. 3) of the cam groove  4   c , as shown in FIG.  5 C. Thus, the fitting operation of the card  11  is finished. 
     Once again, the card  11  is pushed over the maximum stroke and, thereafter, the pushing operation is stopped. In this event, as shown in FIG. 5D, the guide pin  6   b  escapes from the depressed portion ({circle around ( 3 )} in FIG. 3) of the cam groove  4   c . Thereafter, the guide pin  6   b  travels through the guide portion ({circle around ( 4 )} in FIG. 3) to reach the terminal point {circle around ( 5 )}, namely, the start point {circle around ( 1 )} as shown in FIG.  5 E. The card  11  and the eject lever  4  pass through the state of FIG.  4 D and reach the state of FIG. 4E under the restoring force of the compression coil spring  5 . Thus, the ejecting operation of the card  11  is finished. 
     In the foregoing, the cam groove  4   c  is formed on the eject lever  4  and the cam follower  6  is formed on the insulator  2 . Alternatively, the cam groove may be formed on the insulator and the cam follower may be formed on the eject lever.