Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector for use with a memory card. 
     2. Description of the Related Art 
     Conventionally, connectors for use with memory cards are available in various types. For example, one memory card has a locking recess in its side surface. Another memory card does not have such a locking recess in its side surface. If one attempts to connect such memory cards having different contours using one kind of connector, the used connector must have no locking mechanism, for the following reason. A connector having a locking mechanism locks a memory card having a locking recess by its locking pawls, thus preventing the card from coming off. On the other hand, where a memory card having no locking recess is inserted into such a connector, it is considered that the locking mechanism will be destroyed or the side surface of the memory card will be damaged, thus making the card unusable. 
     With a connector not having the aforementioned locking mechanism, however, it is impossible to make effective use of the contour of the memory card having a locking recess. Hence, there is the problem that it is not assured that the card is prevented from coming off. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing problem, it is an object of the present invention to provide a memory card connector which has a locking function and permits both a memory card having a locking recess in its side surface and a memory card having no locking recess in its side surface to be inserted and withdrawn. 
     A connector according to the present invention achieves the above-described object and is used with a memory card having a one-end portion inserted from an opening portion. The connector can electrically connect the input/output interconnects of the card with an external circuit and lock the card. The connector has a connector body provided with a tapering guide groove extending perpendicular to the direction of slide. A slider is slidably mounted to the connector body via a coil spring to thereby form an alternate mechanism. A locking pawl is slidably fitted in the groove of the slider. The pawl is engaged in the tapering guide groove of the connector body via a guide pin. The pawl can engage a locking recess formed in one side surface of the memory card. A spring material is mounted to the slider and constantly biases the locking pawl inward. When the memory card is pushed in and the slider slides, the locking pawl engages the locking recess in the memory card. When the card is pushed out and the slider slides, the locking pawl comes out of the locking recess in the memory card. 
     According to the present invention, therefore, when the memory card having the locking recess is inserted, the locking pawl engages the locking recess and becomes locked. When a memory card having no locking recess is inserted, the locking pawl biased inward by the spring material is moved outward, thus accepting the memory card having no locking recess. Consequently, a connector is obtained with which memory cards with different shapes can be connected. 
     Even where the memory card having the locking recess is inserted, the locking pawl is merely biased by the spring member. Therefore, if the memory card is erroneously pulled out forcibly, the locking pawl is displaced outward. In consequence, the locking mechanism is not destroyed. The memory card is not damaged. 
     The memory card can be electrically connected with the connector in one push via the slider forming the alternate mechanism and the card is locked. Thus, the card is prevented from coming off. Furthermore, the slider is pushed back to its original position by the spring force of the coil spring by giving a push. Consequently, the memory card can be easily removed. Therefore, a connector is obtained which permits a memory card to be inserted and withdrawn easily and which provides convenience in use. 
     In one feature of the invention, the spring member can be a coil spring that gives a biasing force which rotates the locking pawl. 
     The present embodiment offers the advantage that the twisting force of the coil spring of the connector can be utilized and, therefore, the locking pawl can be biased with a desired biasing force even within a narrow space. The connector is easy to design and provides convenience in use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view illustrating a method of using a memory card connector according to the present invention; 
     FIG. 2 is an exploded perspective view taken from above the connector shown in FIG. 1, and in which the memory card is not yet mounted; 
     FIG. 3 is an exploded perspective view taken from below the connector shown in FIG. 1, and in which the card is not yet mounted; 
     FIG. 4 is a plan view of a connector body according to the invention; 
     FIG. 5A is a front elevation of a slider according to the invention; 
     FIG. 5B is a rear view of the slider; 
     FIG. 5C is a plan view of the slider; 
     FIG. 6A is a perspective view taken from above a locking pawl, a guide pin, and a coil spring shown in FIG. 2; 
     FIG. 6B is a perspective view taken from below these components; 
     FIG. 7 is a perspective view taken above a write inhibit switch shown in FIG. 2; 
     FIG. 8 is a perspective view showing the manner in which a memory card is being mounted to the connector shown in FIG. 2; 
     FIG. 9 is a perspective view similar to FIG. 8, but in which the memory card has been mounted to the connector shown in FIG. 2; 
     FIGS. 10A-D shows fragmentary enlarged views illustrating a procedure for mounting a memory card to the connector shown in FIG. 2; 
     FIGS. 11A-B shows fragmentary enlarged views illustrating a procedure for taking a memory card out of the connector shown in FIG. 2; 
     FIG. 12 is a plan view, and in which a memory card set to inhibit writing is mounted to the connector shown in FIG. 2; 
     FIG. 13 is a plan view, and in which a memory card set to enable writing is mounted to the connector shown in FIG. 2; 
     FIG. 14 is a perspective view showing the manner in which a memory card having no locking recess is being mounted to the connector shown in FIG. 2; and 
     FIG. 15 is a perspective view similar to FIG. 14, but in which the memory card having no locking recess has been mounted to the connector shown in FIG.  2 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the present invention are described below by referring to FIGS. 1-15 of the accompanying drawings. 
     An embodiment is illustrated in FIG. 1, where the present invention is applied to a connector  20  for electrically connecting a printed circuit board  10  and a memory card  11 . 
     The printed circuit board  10  comprises an insulating board on which wiring is printed to form multiple interconnects. The memory card  11  is a rectangular card incorporating an IC memory. Ribs  12  are formed on both side surfaces of the card to prevent misinsertion. One side surface of the memory card  11  is provided with a recess  13  for locking purposes. A switch  14  for inhibiting writing is slidably formed on the other side surface. A cutout  15  (FIG. 2) is formed at one corner of the front end of the memory card to judge whether the insertion is incorrect or not. Furthermore, the memory card  11  has a plurality of juxtaposed input/output connection portions or interconnects  16  on its bottom surface (FIG.  3 ). 
     The connector  20  is so designed that a slider  40  is squeezed from above and below by a top shell  21  and a flat, gatelike connector body  36 , as shown in FIG.  2 . The slider  40  is slidably mounted to one arm  31  of the connector body  30 . 
     The top shell  21  has been stamped from a metal sheet and pressed. Resilient pawls  22  and  23  are carved out from near both ends of the top shell  21 . A resilient pawl  24  is carved out from one corner to prevent a lever  51  (described later) from floating. 
     In the present embodiment, the connector is surface-mounted on the printed circuit board. Where connection with a flexible printed circuit (FPC), for example, is made, the connector body  30  may be squeezed from above and below by the top shell  21  and a bottom shell (not shown), and a connector for the FPC may be mounted to the connection end surface. 
     As shown in FIG. 8, the top end of the connector body  30  is provided with plural terminal holes  30   a  formed at a given pitch. Connector terminals  50  are pressed into the terminal holes  30   a  from the outside. As shown in FIG. 4, a support hole  33  (described later) is formed in the top end surface of the arm  31  of the arms  31  and  32  of the connector body  30 , the hole  33  forming a pivot for rotation of the lever  51 . A projection  34  for guiding the slider  40  (described later) is formed near the hole  33 . A tapering guide groove  35  is formed near one end of the projection  34 . A slit  36  for accommodating a coil spring  52  (described later) is formed near one end of the guide groove  35 . A support protrusion  36   a  that supports the coil spring  52  protrudes into the slit  36 . 
     A terminal hole  37  is formed in the base portion of the other arm  32  of the connector body  30 . The bottom surface of a connection portion  53   a  of a fixed contact terminal  53  mounted to the connector body  30  is exposed from the terminal hole  37  so as to be connectable. A first movable contact member  54  and a second movable contact member  55  are mounted near one end of the connector body  30 . The fixed contact terminal  53 , first movable contact terminal  54 , and second movable contact terminal  55  together form a switch used to judge whether the memory card  14  has been set to inhibit writing. As shown in FIG. 7, a movable contact portion  54   a  and a pressure contact portion  54   b  which make contact with the fixed contact terminal  53  are formed on the first movable contact terminal  54  by stamping and bending a conductive spring member. Similarly, a movable contact portion  55   a  and a pressure contact portion  55   b  which make contact with the movable contact terminal  54  are formed on the second movable contact terminal  55  by stamping and bending a conductive spring member. In FIGS. 12 and 13, indicated by  55   c  is an insulating spacer. 
     As shown in FIG. 5, the aforementioned slider  40  is a molded plastic product having a cross-sectional shape capable of slidably fitting over the guide projection  34  of one arm  31  of the connector body  30 . A substantially heart-shaped cam groove  41  for forming an alternate mechanism is formed at one end of the top surface of the slider  40 . As shown in FIG. 5A, this cam groove  41  has a first support point  41   a  at which an operation is started, a second support point  41   b  at which one end  51   b  of the lever  51  moved away from the first support point  41   a  falls, a third support point  41   c  at which one end  51   b  of the lever  51  moved away from the second support point  41   b  falls and settles itself, and a fourth support point  41   d  at which one end  51   b  of the lever  51  moved away from the third support point  41   c  falls. 
     A slide groove  42  engaged by a guide pin  57  is formed in the center of the slider  40 , the pin  57  being mounted on a locking pawl  56  (described later). A support protrusion  43  that supports a coil spring  58  is formed at the other end of the slider  40 . The coil spring  58  biases the locking pawl  56  inward. 
     As shown in FIGS. 5B and 5C, a recess  44  for receiving the coil spring  52  is formed at one end of the bottom surface of the slider  40 . Protrusions  45   a  and  45   b  having the same height protrude from the bottom surface of the slider  40  to prevent the slider  40  itself from tilting. 
     As shown in FIG. 8, the coil spring  52  is fitted over the support protrusion  36   a  of the connector body  30 . Then, the coil spring  58  is mounted to the support protrusion  43  of the slider  40 . The guide pin  57  is mounted with a press fit in a hole  56   a  extending through the locking pawl  56 . The guide pin  57  is fitted into the slide groove  42  in the slider  40 . One end of the coil spring  58  is mounted in an insertion port  56   b  formed in the locking pawl  56 , whereby the locking pawl  56  is biased inward. Then, the slider  40  is slidably mounted on the protrusion  34  on the connector body  30 . At this time, the guide pin  57  is engaged in the guide groove  35 . One end  51   a  of the substantially U-shaped lever  51  is inserted into the support hole  33  in the connector body  30 . The other end  51   b  is anchored to the first support point  41   a  in the heart-shaped cam groove  41 . The top shell  21  is mounted to the connector body  30  and they are assembled as a unit. At this time, the resilient pawl  24  on the top shell  21  is pressed against the lever  51  to limit the position. In this way, disengagement is prevented. 
     The locking pawl  56  is biased inward by the spring force of the coil spring  58  as shown in FIG.  10 . Therefore, when the slider  40  slides into a deeper position, the guide pin  57  moves along the tapering guide groove  35 . As the slider  40  goes deeper, the locking pawl  56  protrudes inward along the slide groove  42  and engages the locking recess  13  in the memory card  11 . 
     The operation performed when the memory card  11  is inserted into the connector  20  composed of the aforementioned components is next described. 
     Before the memory card  11  is inserted, the slider  40  is located near the opening in the connector  20 . The other end  51   b  of the lever  51  is located at the first support point  41   a  in the cam groove  41 . The guide pin  57  is located ahead of the guide groove  35 . 
     When the memory card  11  is inserted from the opening in the connector  20 , the memory card  11  fits over the slider  40 . The resilient pawls  22  and  23  on the top shell  21  push the card  11  against the connector body  30 . If the memory card  11  is pushed in further, the slider  40  slides against the spring force of the coil spring  52 . Concomitantly with this movement, the other end  51   b  of the lever  51  moves from the first support point  41   a  to the second support point  41   b . Also, the guide pin  57  moves along the guide groove  35 . Therefore, the locking pawl  56  biased inward rotates and is pushed forward into the locking recess  13  (FIGS. 10B and 10C) in the memory card  11 , thus preventing the pawl from coming off. At the same time, the input/output interconnects  16  of the memory card  11  come into contact with their respective connector terminals  50 . 
     In the present embodiment, where the insertion of the memory card  11  is done from the wrong side, the cutout  15  bears against the slider  40  to thereby prevent wrong insertion. 
     Where the inserted memory card  11  is turned upside down, the misinsertion preventive ribs  12  formed on both side surfaces of the connector body  30  bear against the edges of the opening in the arms  31  and  32  of the connector body  30 . This creates the advantage that misinsertion is prevented with certainty. 
     When pushing of the memory card  11  is released, the spring force of the coil spring  58  pushes back the slider  40 . However, the other end  51   b  of the lever  51  falls into the third support point  41   c  from the second support point  41   b  (FIG.  10 D), thus hindering return of the slider  40 . Therefore, the locking pawl  56  remains engaged in the locking recess  13 . The memory card  11  is locked. There is no fear of the card coming off. 
     At this time, the locking pawl  56  is merely biased by the spring force of the coil spring  58  and so if the memory card  11  is forcibly pulled out, the locking pawl  56  is pushed back. There is no fear of the pawl becoming damaged. 
     As shown in FIG. 12, where the memory card  11  is mounted within the connector  20 , the card  11  bears against the pressure contact portion  55   b  of the second movable contact terminal  55 , and the movable contact portion  55   a  comes into contact with the first movable contact terminal  54 . Therefore, insertion of the memory card  11  can be detected. Since the switch  14  for inhibiting writing is located in its forward position, the switch  14  is not pressed against the pressure contact portion  54   b  of the first movable contact terminal  54 . Consequently, the movable contact portion  54   a  does not touch the fixed contact  53 . It is possible to detect that the card is in a write inhibit condition. 
     If the write-inhibit switch  14  is located on the side of insertion as shown in FIG. 13, the switch  14  bears against the pressure contact portion  54   b  of the first movable contact terminal  54 . Therefore, the movable contact portion  54   a  comes into contact with the fixed contact terminal  53 . It is possible to detect that the card is in a writable condition. 
     When the memory card  11  is pushed in again, the other end  51   b  of the lever  51  moves from the third support point  41   c  to the fourth support point  41   d . Concurrently, the locking pawl  56  is greatly pushed out into the locking recess  13  (FIG.  11 A). However, when pushing of the memory card  11  is released, the other end  51   b  of the lever  51  returns to the first support portion  41   a  from the fourth support portion  41   d  (FIG.  11 B). The spring force of the coil spring  52  pushes back the slider  40 . The guide pin  57  is moved back along the guide groove  35 . As a result, the locking pawl  56  slides within the slide groove  42  and retracts. This unlocks the memory card  11 . It is possible to take out the card  11  by lightly pulling it out against the spring force of the resilient pawls  22  and  23 . 
     Since the resilient pawls  22  and  23  push against the memory card  11 , if it is pushed back by the spring force of the coil spring  52 , there is no danger that the memory card  11  will be ejected from the connector  20 . 
     The case where the memory card  16  is not provided with a locking recess is next described by referring to FIGS. 14 and 15. 
     Before the memory card  16  is inserted, the slider  40  is located near the opening in the connector  20  in the same way as the foregoing. The other end  51   b  of the lever  51  is located at the first support point  41   a  in the cam groove  41 . The guide pin  58  is located ahead of the guide groove  35 . 
     When the memory card  16  not provided with a locking recess is inserted, the card  16  fits over the slider  40 . The resilient pawls  22  and  23  on the top shell  21  press the card  16  against the connector body  30 . If the card  16  is pushed in further, the slider  40  slides against the spring force of the coil spring  52 . Concomitantly with this movement, the other end  51   b  of the lever  51  moves from the first support point  41   a  to the second support point  41   b . The guide pin  57  moves along the guide groove  35 . Therefore, the locking pawl  56  biased inward rotates. However, the locking pawl  56  is merely pressed against the memory card  16 , because the card  16  has no locking recess. The input/output interconnects  16  of the memory card  16  are connected with their respective connector terminals  50 . 
     When pushing of the memory card  16  is released, the spring force of the coil spring  58  pushes back the slider  40 . The other end  51   b  of the lever  51  falls into the third support point  41   c  from the second support point  41   b . This hinders return of the slider  40 . At this time, the locking pawl  56  does not engage a locking recess but the memory card  16  is pressed against the connector body  30  by the resilient pawls  22  and  23 . Consequently, there is no fear of the card coming off. 
     At this time, if the memory card  16  is forcibly pulled out, there is no danger of the locking pawl  56  being destroyed because it is merely pressed against the card  16 . If the memory card  11  having the locking recess  13  is inserted immediately thereafter, the locking pawl  56  can be pushed back and mounted to the slider  40  that has been locked, because the locking pawl  56  is merely biased inward. Similarly, if the memory card  16  having no locking recess is inserted, the locking pawl  56  can be pushed back and mounted to the slider  40  that has been locked. 
     When the memory card  16  is mounted within the connector  20 , one side surface of the card  16  bears against the pressure contact portion  54   b  of the first movable contact terminal  54 , and the movable contact portion  54   a  touches the fixed contact terminal  53 . Furthermore, one side surface of the memory card  16  bears against the pressure contact portion  55   b  of the second movable contact terminal  55 . Therefore, the movable contact portion  55   a  comes into contact with the first movable contact terminal  54 . 
     If the memory card  16  is pushed in again, the other end  51   b  of the lever  51  moves from the third support point  41   c  to the fourth support point  41   d . If pushing of the memory card  16  is released, the other end  51   b  of the lever  51  returns to the first support portion  41   a  from the fourth support portion  41   d . Therefore, the slider  40  is pushed back by the spring force of the coil spring  52 . The memory card  16  protrudes out of the connector  20 . It is possible to take out the memory card  16  by lightly pulling it out against the spring force of the resilient pawls  22  and  23 . 
     Since the memory card  16  is pressed against the connector body  30  by the resilient pawls  22  and  23 , if the card  16  is pushed back by the force of the coil spring  52 , there is no danger that the card  16  will be ejected out of the connector  20 . 
     In the present embodiment described thus far, the resilient pawls  22  and  23  prevent the memory cards  11  and  16  from being ejected. It is to be understood that the resilient pawls  22  and  23  are not essential. They may be mounted if necessary. 
     According to the present invention, the locking pawl engages the locking recess and becomes locked where a memory card provided with a locking recess is inserted. Where a memory card provided with no locking recess is inserted, the locking pawl biased inward by a spring material is pressed against the side surface of the memory card. In this way, the memory card not formed with a locking recess is accepted. Therefore, there is the advantage that a connector is obtained with which memory cards having different contours can be connected.

Technology Category: 5