Abstract:
A card connector includes a required number of contacts adapted to contact connection portions of the plurality of the memory cards, and a case arranging and holding the contacts therein and having a plurality of inserting holes for the memory cards. The connector includes at least one locking member movable or pivotally movable when a memory card is inserted, and at least one spring member displaceable when the memory card is inserted. In one aspect, a card connector includes at least one slider for forming parts of the plurality of inserting holes, and at least one holder for movably holding the slider. Consequently, the card connector is able to prevent the insertion of more than one memory card with a simple construction, to provide a miniaturized and high-density connector without any limitation of circuit board design, and easy to design its case and easy to remove the inserted card.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to a card connector for use in a various kinds of electric and electronic appliances such as printers, card readers and the like and capable of inputting and outputting signals into and from a plurality of memory cards inserted into the card connector, and more particularly to a card connector capable of preventing more than one memory card from being inserted at a time.  
         [0002]     In recent years, with the widespread use of digital cameras and the like, memory cards of compact and large memory capacity have been used. Depending upon characteristics of appliances with which the memory cards are utilized, memory cards of variety of kinds have become popular such as, for example, SD (Secure Digital) memory card (registered trademark) (simply referred to hereinafter as “SD card”), Memory-Stick card (registered trademark) (simply referred to hereinafter as “MS card”), SmartMedia card (registered trademark) (simply referred to hereinafter as “SM card”), CompactFlash card (registered trademark) (simply referred to hereinafter as “CF card”), xD card (registered trademark), multimedia card (registered trademark) (simply referred to hereinafter as “MM card”) and the like. With these circumstances, memory card readers and writers as devices for reading and writing information from and onto these various memory cards have been used in computers or as external or peripheral devices.  
         [0003]     It is naturally preferable that such memory card readers and writers can also accommodate these various memory cards. In the hitherto used memory card readers and writers, therefore, there is arranged a card connector in their main body to make it possible to insert various memory cards into the connector, thereby enabling writing and reading information onto and from these memory cards.  
         [0004]     There are many kinds of memory cards such as SD, MS, SM, CF, xD, MM cards and the like described above. The memory card readers and writers could accommodate all or some of these memory cards. In fact, card connectors are provided with inserting holes into which corresponding memory cards can be inserted. Now, a card connector adapted to accommodate three kinds of the SD, xD and MS cards will be explained by way of example with reference to  FIGS. 6 and 7 .  
         [0005]     A card connector  60  of the prior art shown in  FIGS. 6 and 7  includes a plurality of contacts  63  arranged and held in a housing or a case  62  such that the contacts  63  are able to be connected to terminals of memory cards inserted into respective inserting holes. In this case, the card connector is constructed such that when a memory card is inserted into the inserting hole through its opening, it becomes possible to write and read information onto and from the memory card. As shown in  FIG. 7 , the card connector  60  includes an inserting hole  27  in the upper portion for an SD card  49 , an inserting hole  26  on the left side in the lower portion for an MS card  48 , and an inserting hole  25  on the right side in the upper portion for an xD card  47 .  
         [0006]     With such a card connector, a desired memory card, for example, the CF card is inserted into the inserting hole for the CF card to carry out writing and reading information onto and from the CF card. In a card connector into which a plurality of memory cards can be inserted, integrated circuits for controlling the respective memory cards are common to all the memory cards. When two or more memory cards are inserted into the card connector at a time, errors would frequently occur. Two methods are envisioned in order to avoid these errors. One method is to provide integrated circuits exclusive to the respective memory cards for controlling these cards. The other method is to prevent the insertion of more than one memory card at a time. The former method would be difficult to be realized because of extremely packed substrate layouts and occupied areas of substrates with the current progressed miniaturization of appliances and would result in increase of manufacturing cost.  
         [0007]     As an example of the latter method, consequently, disclosed in the art is a card connector having a plurality of inserting holes and planned to prevent a further insertion of a memory card when once a memory card has been inserted, such as Japanese Patent Application Opened No. 2003-297,489 (Patent Literature 1).  
         [0008]     The invention of the Japanese Patent Application Opened No. 2003-297,489 (Patent Literature 1) has an object to provide a memory card connector having a plurality of inserting holes into which a plurality of memory card can be inserted, but being capable of preventing a second memory card from being inserted by an earlier insertion of a first memory card. This memory card connector includes a connector main body having a plurality of inserting holes opening into shapes corresponding to those of memory cards to be inserted and contacts provided in spaces of the inserting holes to be electrically connected to respective electrodes of the cards to be inserted, and a slide cover provided outside the inserting holes in a movable manner along the opening surface of the inserting holes and having card inserting holes of shapes corresponding to the memory cards, the card inserting holes opening in a manner forming pairs with and shifting relative to the inserting holes of the connector main body. With this construction, accordingly, when the space of one inserting hole of the connector main body and the card inserting hole of the slider cover are concentrically coincident with each other, the spaces of the other inserting holes of the main body and the other card inserting holes of the slide cover are not coincident with each other, thereby preventing the insertion of more than one memory card at a time. The claim in the Patent Literature 1 recites a memory card connector into which a plurality of memory cards can be inserted, characterized in comprising a connector main body consisting of a plastic housing or case having a plurality of inserting holes opening into shapes corresponding to those of memory cards to be inserted and contacts provided in spaces of the inserting holes to be electrically connected to electrodes of the cards to be inserted, and a slide cover provided outside the inserting holes of the connector main body in a movable manner along the opening surface of the inserting holes of the connector main body and having card inserting holes of shapes corresponding to the memory cards to be inserted and opening in a manner forming pairs with the inserting holes of the connector main body, whereby when the space in one inserting hole of the connector main body and the card inserting hole of the slide cover in pair are concentrically coincident with each other, other spaces of the other inserting holes and the opposite card inserting holes are not coincident with each other.  
         [0009]     In the card connector of the Patent Literature 1, the slide cover as a separate part is attached to the surface of the case and is laterally slid such that only one card inserting hole of the slide cover is brought into coincidence with the one inserting hole of the case and the other card inserting holes are not coincident with the other inserting holes of the case, thereby preventing the insertion of more than one memory card at a time.  
         [0010]     In recent years, the requirement for even more miniaturization has been more strongly imposed on appliances and hence the same requirement has also been strongly imposed on connectors. Under such circumstances, the arrangement of the slide cover on the front surface of the connector in the Patent Literature 1 would go against the miniaturization of connector, and would limit circuit substrate design (making it impossible to arrange connection portions of the connector to a substrate on the side of fitting with a mating connector) and inhibit the high-density arrangement for accommodating a plurality of memory cards.  
         [0011]     In order to cause the slide cover to slide on the surface of the case, moreover, the front surface of the case must extend onto the side inserting the memory cards, which makes it structurally difficult to design the connector case and results in deteriorated shielding effect.  
         [0012]     With the construction of the card connector of the Patent Literature 1, moreover, the slide cover as a separate part is arranged on the surface of the case so that when removing a memory card from the card connector, the part of the card to be grasped or seized by an operator would be reduced, making it difficult to remove the card from the connector.  
       SUMMARY OF THE INVENTION  
       [0013]     It is an object of the invention to provide an improved card connector which eliminates all the disadvantages of the prior art described above and which is able to prevent the insertion of a further card with a simple construction when a first card has been inserted, to achieve a miniaturized and high-density connector without any limitation of circuit board design, and easy to design its case and easy to remove the inserted card.  
         [0014]     The object of the invention above described can be accomplished by a card connector  10  into which a plurality of memory cards are removably inserted, including a required number of contacts  13  adapted to contact connection portions of the plurality of the memory cards  45 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  23  into which the plurality of memory cards  45  are inserted, respectively, wherein according to the invention, the card connector comprises at least one locking member  20  provided at a predetermined position in the case  12  to be movable or pivotally movable when a memory card  45  of one kind is inserted, and at least one spring member  18  provided at a predetermined position in the case  12  to be displaceable when the memory card  45  of the one kind is inserted, thereby preventing more than one memory card from being inserted into the card connector by means of the locking member  20  and the spring member  18 .  
         [0015]     In the case having three inserting holes, the object described above can be achieved by a card connector  10  into which a plurality of memory cards  45  are removably inserted, including a required number of contacts  13  adapted to contact connection portions of the plurality of the memory cards  45 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  23  into which the plurality of memory cards  45  are inserted, respectively, wherein according to the invention, the case  12  comprises two inserting holes  23  arranged substantially side by side and one inserting hole  23  arranged above the two inserting holes, and the case further comprises a locking member  20  provided at an intermediate position of the two inserting holes to be movable or pivotally movable when a memory card  45  is inserted into either of the two inserting holes  23 , and a spring member  18  provided at a position below the one inserting hole  23  arranged above the two inserting holes  23  to be displaceable when a memory card  45  is inserted into the one inserting hole  23 , thereby preventing more than one memory card  45  from being inserted into the card connector by means of the locking member  20  and spring members  18 .  
         [0016]     In a preferred embodiment, when a memory card  45  is inserted into either of the inserting holes  23  of the case  12 , the locking member  20  is moved or pivotally moved to extend into the inserting hole  23  arranged in the side by side relationship to the inserting hole  23  into which the memory card has been inserted so that the spring member  18  is prevented from being displaced by means of the locking member  20 , thereby preventing more than one memory card  45  from being inserted into the card connector.  
         [0017]     In another embodiment, when a memory card  45  is inserted in either of the inserting holes  23  of the case  12 , the spring member  18  is displaced so that parts of the displaced spring member  18  extend into other inserting holes  23 , thereby preventing more than one memory card  45  from being inserted into the card connector. Moreover, the inserting holes  23  have a common portion to other inserting holes  23 , if required.  
         [0018]     Moreover, the object of the invention can be achieved by a card connector  10  into which a plurality of memory cards  50  are removably inserted, including a plurality of contacts  13  adapted to contact connection portions of the plurality of the memory cards  50 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  122  into which the plurality of memory cards  50  are inserted, respectively, wherein according to the invention, the card connector comprises a required number of sliders  120  arranged at predetermined positions in the case  12  for forming parts of the plurality of inserting holes  122 , and a required number of holders  118  arranged at predetermined positions in the case  12  for movably holding the sliders  120 , thereby preventing more than one memory card  50  from being inserted into the card connector by means of the sliders  120 .  
         [0019]     In the case having five inserting holes  122 , the object described above can be accomplished by a card connector  10  into which a plurality of memory cards  50  are removably inserted, including a plurality of contacts  13  adapted to contact connection portions of the plurality of the memory cards  50 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  122  into which the plurality of memory cards  50  are inserted, respectively, wherein according to the invention, the case  12  comprises four inserting holes  122  arranged side by side and one above the other and one inserting hole  122  arranged below and at an intermediate position of the four inserting holes  122 , and the case  12  further comprises a required number of sliders  120  arranged substantially at an intermediate position of the four inserting holes  122  arranged side by side and forming parts of the five inserting holes  122 , and a holder  118  for movably holding the slider  120 , thereby preventing more than one memory card  50  from being inserted into the card connector by means of the slider  120 .  
         [0020]     In a preferred embodiment, a combination of the recesses  130  and the protrusion  132  forms the parts of the inserting holes  122 . Moreover, four recesses  130  form the parts of the four inserting holes  122  arranged side by side and one above the other, and one protrusion  132  forms the part of the inserting hole  122  arranged below the four inserting holes  122 . Further, the front end of the holder  118  is divided into pieces which are alternately bent in opposite directions, and the slider  120  is formed with an inserting aperture  128  into which the holder  118  is inserted such that the slider  120  is movably held.  
         [0021]     In another embodiment, the front end of the holder  118  is divided into three pieces which are alternately bent in opposite directions, and the slider  120  is formed with a longitudinally elongate inserting aperture  128  into which the holder  118  is inserted such that the slider  120  is held movably in its longitudinal direction (direction of the thickness of the connector). Further, a combination of the recesses  130  and the protrusion  132  formed in the slider  120  forms the parts of the inserting holes  122  for memory cards  50  so that when the slider  120  is moved by inserting one memory card  50  into one inserting hole  122 , any memory card cannot be inserted into any other inserting holes  122 .  
         [0022]     As can be seen from the above explanation, the card connector  10  according to the invention can bring about the following significant effects.  
         [0023]     (1) According to the invention, the card connector comprises at least one locking member  20  provided at a predetermined position in the case  12  to be movable or pivotally movable when a memory card  45  of one kind is inserted, and at least one spring member  18  provided at a predetermined position in the case  12  to be displaceable when the memory card  45  of the one kind is inserted, thereby preventing the insertion of more than one memory card into the card connector by means of the locking member  20  and the spring member  18 . In this manner, as the insertion of more than one memory card  45  can be prevented with great certainty, no errors occur in integrated circuits for controlling the memory cards  45 , and the card connector according to the invention can be designed without any limitation in circuit board design and without any obstacle in high-density construction and is easy to design the case and easy to remove memory card.  
         [0024]     (2) According to the invention, the case  12  comprises two inserting holes  23  arranged substantially side by side and one inserting hole  23  arranged above the two inserting holes, and the case further comprises a locking member  20  provided at an intermediate position of the two inserting holes to be movable or pivotally movable when a memory card  45  is inserted into either of the two inserting holes  23 , and a spring member  18  provided at a position below the one inserting hole  23  arranged above the two inserting holes  23  to be displaceable when a memory card  45  is inserted into the one inserting hole  23 , thereby preventing the insertion of more than one memory card  45  into the card connector by means of the locking member  20  and spring members  18 . In this manner, as the insertion of more than one memory card  45  can be prevented with great certainty, no errors occur in integrated circuits for controlling the memory cards  45 , and the card connector according to the invention can be designed without any limitation in circuit board design and without any obstacle in high-density construction and is easy to design the case and easy to remove memory card.  
         [0025]     (3) According to the invention, when a memory card  45  is inserted into either of the inserting holes  23  of the case  12 , the locking member  20  is moved or pivotally moved to extend into the inserting hole  23  arranged in the side by side relationship to the inserting hole  23  into which the memory card has been inserted so that the spring member  18  is prevented from being displaced by means of the locking member  20 , thereby preventing the insertion of more than one memory card  45  into the card connector. Therefore, as the insertion of more than one memory card  45  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  45 , and circuit board design and case design can be easily performed without any objection.  
         [0026]     (4) According to the invention, when a memory card  45  is inserted in either of the inserting holes  23  of the case  12 , the spring member  18  is displaced so that parts of the displaced spring member  18  extend into other inserting holes  23 , thereby preventing the insertion of more than one memory card  45  into the card connector. Consequently, as the insertion of more than one memory card  45  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  45 , and circuit board design and case design can be easily performed without any objection.  
         [0027]     (5) According to the invention, the inserting holes  23  have a common portion to other inserting holes  23 , if required. Therefore, the card connector according to the invention accommodate many kinds of memory cards  45  without enlarging the connector.  
         [0028]     (6) In the card connector  10  into which a plurality of memory cards  50  are removably inserted, including a plurality of contacts  13  adapted to contact connection portions of the plurality of the memory cards  50 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  122  into which the plurality of memory cards  50  are inserted, respectively, according to the invention the card connector comprises a required number of sliders  120  arranged at predetermined positions in the case  12  for forming parts of the plurality of inserting holes  122 , and a required number of holders  118  arranged at predetermined positions in the case  12  for movably holding the sliders  120 , thereby preventing the insertion of more than one memory card  50  into the card connector by means of the sliders  120 . In this manner, as the insertion of more than one memory card  50  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  50 , and the card connector according to the invention can be designed without any limitation in circuit board design and without any obstacle in high-density construction and is easy to design the case and easy to remove memory card  50 .  
         [0029]     (7) In a card connector  10  into which a plurality of memory cards  50  are removably inserted, including a plurality of contacts  13  adapted to contact connection portions of the plurality of the memory cards  50 , and a case  12  arranging and holding the contacts  13  therein and having a plurality of inserting holes  122  into which the plurality of memory cards  50  are inserted, respectively, according to the invention the case  12  comprises four inserting holes  122  arranged side by side and one above the other and one inserting hole  122  arranged below and at an intermediate position of the four inserting holes  122 , and the case  12  further comprises a required number of sliders  120  arranged substantially at an intermediate position of the four inserting holes  122  arranged side by side and forming parts of the five inserting holes  122 , and a holder  118  for movably holding the slider  120 , thereby preventing the insertion of more than one memory card  50  into the card connector by means of the slider  120 . In this manner, as the insertion of more than one memory card  50  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  50 , and the card connector according to the invention can be designed without any limitation in circuit board design and without any obstacle in high-density construction and is easy to design the case and easy to remove memory card  50 .  
         [0030]     (8) According to the invention, a combination of the recesses  130  and the protrusion  132  forms the parts of the inserting holes  122 , thereby preventing the insertion of more than one memory card  50 . Therefore, as the insertion of more than one memory card  50  can be prevented, no errors occur in integrated circuits for controlling the memory cards  50 , and circuit board design and case design can be easily performed without any objection.  
         [0031]     (9) According to the invention, four recesses  130  form the parts of the four inserting holes  122  arranged side by side and one above the other, and one protrusion  132  forms the part of the inserting hole  122  arranged below the four inserting holes  122 . Consequently, as the insertion of more than one memory card  50  can be prevented, no errors occur in integrated circuits for controlling the memory cards  50 , and circuit board design and case design can be easily performed without any objection.  
         [0032]     (10) According to the invention, the front end of the holder  118  is divided into pieces which are alternately bent in opposite directions, and the slider  120  is formed with an inserting aperture  128  into which the holder  118  is inserted such that the slider  120  is movably held. Therefore, as the insertion of more than one memory card  50  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  50 , and circuit board design and case design can be easily performed without any objection.  
         [0033]     (11) According to the invention, the front end of the holder  118  is divided into three pieces which are alternately bent in opposite directions, and the slider  120  is formed with a longitudinally elongate inserting aperture  128  into which the holder  118  is inserted such that the slider  120  is held movably in its longitudinal direction (direction of the thickness of the connector). Consequently, as the insertion of more than one memory card  50  can be prevented with a simple construction with great certainty, no errors occur in integrated circuits for controlling the memory cards  50 , and circuit board design and case design can be easily performed without any objection.  
         [0034]     (12) According to the invention, a combination of the recesses  130  and the protrusion  132  formed in the slider  120  forms the parts of the inserting holes  122  for memory cards  50  so that when the slider  120  is moved by inserting one memory card  50  into one inserting hole  122 , any memory card cannot be inserted into any other inserting holes  122 . Therefore, the slider  120  can be easily held movably onto the case  12 , and only by moving the slider  120 , the insertion of more than one memory card  50  can be prevented, with the result that no errors occur in integrated circuits for controlling the memory cards  50 , and circuit board design and case design can be easily performed without any objection.  
         [0035]     The invention will be more fully understood by referring to the following detailed specification and claims taken in connection with the appended drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0036]      FIG. 1A  is a perspective view of a card connector viewed from above on the fitting side;  
         [0037]      FIG. 1B  is the perspective view of the card connector viewed from below on the fitting side;  
         [0038]      FIG. 2  is a view for explaining mounting of a spring member and a locking member onto the card connector according to the invention;  
         [0039]      FIG. 3  is a front view for explaining an occasion inserting a plurality of memory cards into the card connector according to the invention;  
         [0040]      FIG. 4  is a front view for explaining the card connector with a memory card inserted into an inserting hole arranged in the upper portion;  
         [0041]      FIG. 5A  is a front view for explaining the card connector with a memory card inserted into an inserting hole on one side in the lower portion;  
         [0042]      FIG. 5B  is a bottom plan view of the card connector shown in  FIG. 5A ;  
         [0043]      FIG. 6  is a perspective view of a card connector of the prior art viewed from above on the fitting side;  
         [0044]      FIG. 7  is a front view for explaining an occasion inserting a plurality of memory cards into the card connector of the prior art;  
         [0045]      FIG. 8  is a perspective view of a card connector according to a further embodiment of the invention viewed from above on the fitting side;  
         [0046]      FIG. 9  is a perspective view of a slider and a holder used in the card connector of the embodiment;  
         [0047]      FIG. 10  is a front view of the card connector of the embodiment of the invention; and  
         [0048]      FIGS. 11A  to  11 E are enlarged views of the part A in  FIG. 10  for explaining states of the slider when a memory card has been inserted into each of the inserting holes of the card connector. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0049]     One embodiment of the card connector according to the invention will be explained with reference to FIGS.  1  to  5 .  FIG. 1A  is a perspective view of the card connector according to the invention viewed from above on its fitting side and  FIG. 1B  is a perspective view of the card connector according to the invention viewed from below on the fitting side.  FIG. 2  is a view for explaining mounting of a spring member and a locking member on the card connector according to the invention.  FIG. 3  is a front view for explaining the occasion inserting a plurality of memory cards into the card connector according to the invention.  FIG. 4  is a front view for explaining the card connector with a memory card inserted in one inserting hole in the upper portion of the card connector.  FIG. 5A  is a front view for explaining the card connector with a memory card inserted in one inserting hole on one side in the lower portion of the card connector and  FIG. 5B  is a bottom plan view of the connector in FIG. A.  
         [0050]     The card connector  10  of the one embodiment of the invention mainly comprises a case  12 , contacts  13  of many kinds, a locking member  20  and a spring member  18 .  
         [0051]     First, the locking member  20  will be explained, which is a subject matter of the invention. The locking member  20  is injection molded from an electrically insulating plastic material in the conventional manner. The material for the locking member  20  is suitably selected in consideration of dimensional stability, workability, manufacturing cost and the like. In general, preferred materials from which to form the locking member  20  include polybutylene terephthalate (PBT), polyamide (66 PA or 46 PA), liquid crystal polymer (LCP), polycarbonate (PC) and the like and combinations thereof.  
         [0052]     The locking member  20  is substantially in the form of a triangular plate which is formed near its one vertex  34  with an aperture  32  into which a fixation pin  22  is inserted. The locking member  20  is rotatable about the aperture  32  (the fixation pin  22 ) when the locking member  20  is mounted on the case  12  by means of the fixation pin  22 . In other words, there is a clearance between the aperture  32  and the fixation pin  22  to permit rotation of the locking member  20  relative to the case  12 . In the case that a memory card  45  is inserted in either of inserting holes  23  arranged side by side in the case  12  for memory cards as shown in  FIGS. 5A and 5B , the inserted memory card  45  abuts against one vertex  34  of the locking member other than the vertex  34  formed with the aperture  32  so that the locking member  20  is pivotally moved to cause the remaining vertex  34  to extend into another inserting hole  23 . In this manner, as a function of the locking member  20 , a memory card is prevented from being inserted into the inserting holes  23  other than that into which the memory card  45  has already been inserted. The size of the locking member  20  is suitably designed in consideration of its function, the size of the card connector  10 , a spacing between the inserting holes arranged in side by side, and the like. The locking member  20  is inserted into the case  12  in the direction shown by an arrow B and fixed thereto.  
         [0053]     While the locking member  20  is of the substantially triangular plate and pivotally mounted on the case  12  in the above explanation, it is to be understood that the locking member  20  may have other features insofar as it can perform the function described above. For example, the locking member may be a substantially rectangular plate which may be formed with an aperture  32  at its center and the aperture  32  may be elliptical so that the rectangular locking member may be laterally moved without being pivotally moved. In more detail, when a memory card  45  is inserted into one of inserting holes  23  arranged side by side, the inserted memory card laterally pushes the locking member  20  so that the locking member  20  moves laterally to partly extends into another inserting hole  23 , thereby preventing a memory card from being inserted into the another inserting hole  23 .  
         [0054]     The spring member  28  will be explained, which is another subject matter of the invention. The spring member  18  is made of a metal and formed by the press-working in the conventional manner. Preferred materials from which to form the spring member  18  include brass, beryllium copper, phosphor bronze and the like to fulfil the requirements imposed thereon, such as springiness, formability and the like. The spring member  18  is substantially L-shaped and includes a fixed portion  29  to be fixed to the case  12 , an elastic portion  28  and two extending portions  30  extending in both width directions. The spring member  18  is inserted in the direction shown by an arrow A in  FIG. 2  between the inserting holes  23  provided side by side in the lower portion of the connector as shown in  FIGS. 1A and 1B  and fixed thereto such that the elastic portion  28  of the spring member  18  extends into the inserting hole  23  in the upper portion of the connector. The spring member  18  is fixed to the case  12  by press-fitting, lancing (hooking) or the like.  
         [0055]     The spring member  18  functions in the following manner. When a memory card  45  is inserted into the inserting hole  23  in the upper portion of the connector, the memory card  45  presses the elastic portion  28  of the spring member  18  downward to cause the spring member  18  to displace downward so that the two extending portions  30  of the spring member  18  extend into the inserting holes  23  arranged side by side in the lower portion of the connector, thereby preventing a memory card  45  from being inserted into the inserting holes  23  in the lower portion under the condition that the memory card has been already inserted in the inserting hole in the upper portion of the connector.  
         [0056]     The spring member  18  further functions in the following manner. When a memory card  45  is inserted in either of the inserting holes  23  arranged side by side in the lower portion of the connector, the extending portion  30  of the spring member  18  abuts the inserted memory card  45  to preclude the displacement of the elastic portion  28  of the spring member  18 , thereby making it impossible to insert a memory card  45  into the inserting hole  23  in the upper portion of the connector.  
         [0057]     The displacement of the elastic portion  28  of the spring member  18  may be suitably designed in consideration of its functions. The displacement is 1.05 mm in the illustrated embodiment. Moreover, the shape and size of the extending portions  30  of the spring member  18  may be suitably designed in consideration of the functions described above. The size of the extending portions  30  is 0.8 mm in the illustrated embodiment.  
         [0058]     Although when a memory card  45  has been inserted into the inserting hole in the upper portion of the connector, the insertion of a memory card  45  into the inserting holes  23  arranged side by side in the lower portion of the connector is prevented by the spring member  18  in the illustrated embodiment, it is to be understood that spring members  18  may be arranged in the respective inserting holes  23  arranged side by side in the lower portion of the connector to cause the spring members  18  to perform the functions described above. In that case, the extending portions  30  of the spring members  18  may be provided in the direction of the displacement, not in the direction of the width.  
         [0059]     The case  12  will then be explained. The case  12  is injection molded from an electrically insulating plastic material in the conventional manner. The material for the case member  12  is suitably selected in consideration of dimensional stability, workability, manufacturing cost and the like. In general, preferred materials from which to form the case  12  include polybutylene terephthalate (PBT), polyamide (66 PA or 46 PA), liquid crystal polymer (LCP), polycarbonate (PC) and the like and combinations thereof.  
         [0060]     The case  12  is formed with a required number of inserting holes  23  for a plurality of memory cards  45 , respectively. The inserting holes  23  are shaped and sized to commensurate with the respective memory cards  45 . Kinds of the memory cards  45  to be inserted into the inserting holes  23  in the embodiment will be explained referring to  FIG. 3 . The inserting hole  24  in the upper portion of the connector is for a CF card  46 , while the inserting hole  25  on the right side in the lower portion is for an xD card  47 . The two inserting holes  26  and  27  arranged on the left side in the lower portion have some common cards to be inserted, and for an MS card  48  and an SD card or an MM card  49 .  
         [0061]     The case  12  is formed with inserting grooves  36  for locating a plurality of contacts  13  fixed therein by press-fitting, hooking (lancing), welding or the like.  
         [0062]     The case  12  is formed with an inserting aperture  38  for fixing the spring member  18  therein. The position of the inserting aperture  38  may be suitably designed in consideration of the functions of the spring member  18 , the strength of the insulating body of the case  12 , the miniaturization of the connector  10  and the like. In the illustrated embodiment, the spring member is provided between the inserting holes  23  arranged side by side in the lower portion of the connector as described above and shown in  FIG. 2 . The size of the inserting aperture  38  may be designed in consideration of the holding force of the spring member  18 .  
         [0063]     Moreover, the case  12  is formed with a mounting hole  40  for mounting the locking member  20 . The position of the mounting hole  40  may be suitably designed in consideration of the functions of the locking member  20 , the strength of the insulating body of the case  12 , the miniaturization of the connector  10  and the like. In the illustrated embodiment, the mounting hole  40  is provided between the inserting holes  23  arranged side by side and on the lower side of the connector  10  as described above and shown in  FIG. 2 . The size of the mounting hole  40  may be designed in consideration of the shape of the locking member  20  and the strength of the insulating body of the case  12  such that the locking member is pivotally movable or displaceable. Moreover, there is provided a fixing aperture in the mounting hole  40  for receiving the fixation pin  22  for mounting the locking member  20  onto the case  12 .  
         [0064]     The plurality of the contacts  13  will then be explained. The plurality of the contacts  13  are made of a metal and formed by the press-working in the conventional manner. Preferred materials from which to form the contacts  13  include brass, beryllium copper, phosphor bronze and the like to fulfil the requirements imposed thereon, such as springiness, conductivity and the like.  
         [0065]     The plurality of contacts  13  each include a contact portion  42  adapted to contact the connection portion of a memory card  45 , a fixed portion to be fixed to the case  12 , and a connection portion  44  to be connected to a board or substrate. As the case  12  has a plurality of inserting holes  23 , among the plurality of contacts  13 , CF card contacts  14 , xD card contacts  15 , MS card contacts  16 , and SD or MM card contacts  17  are fixed at predetermined positions. The connection portions  44  of the respective contacts  14 ,  15 ,  16  and  17  may be suitably designed in consideration of the circuit design of a substrate, occupied areas, the size and design of the connector  10 . In the illustrated embodiment, the connection portions  44  of the CF card contacts  14  are arranged on the opposite side of the entry of the inserting hole  23 , while the connection portions  44  of the xD card contacts  15  are arranged on the entry side of the inserting hole  23 . The connection portions  44  of the MS card contacts  16  are arranged on the opposite side of the entry of the inserting hole  23 , while the connection portions  44  of the SD or MM card contacts  17  are arranged on the entry side of the inserting hole  23 .  
         [0066]     Finally, the functions of the locking member  20  and the spring member  18  will be again explained with reference to  FIGS. 4 and 5 .  
         [0067]     First, the case that the memory card  45  has been inserted in the inserting hole in the upper portion of the connector will be explained. When the memory card  45  is inserted into the inserting hole  23  in the upper portion of the connector as shown in  FIG. 4 , the memory card  45  causes the elastic portion  28  of the spring member  18  to be displaced downward so that the extending portions  30  of the spring member  18  extend into the inserting holes  23  arranged side by side in the lower portion of the connector, thereby preventing a memory card from being inserted into the inserting holes  23  in the lower portion of the connector.  
         [0068]     Next, the case that a memory card  45  has been inserted into either of the inserting holes in the lower portion of the connector will be explained. When the memory card  45  is inserted into the inserting hole  23  on the left side in the lower portion, the memory card  45  causes the locking member  20  to be pivotally moved as shown in  FIG. 5B  so that part of the locking member  20  extends into the inserting hole  23  on the right side in the lower portion, thereby preventing a memory card  45  from being inserted into the inserting hole  23  on the right side in the lower portion. At the same time, the memory card  45  inserted in the inserting hole  23  on the left side in the lower portion prevents the spring member  18  from being displaced (that is, the memory card  45  prevents the extending portion  30  of the spring member  18  from lowering so that the elastic portion  28  of the spring member  18  could not be displaced), thereby preventing a memory card  45  from being inserted into the inserting hole  23  in the upper portion of the connector.  
         [0069]     While the card connector  10  including the case  12  provided with the three inserting holes  23  for memory cards are explained and illustrated in the above embodiment, it will be apparent that the number of the inserting holes is not limited. With a combination of plural members having the constructions of the spring members  18  and the locking member  20  described above, it is possible to suitably design a card connector capable of preventing a memory card from being inserted after one memory card has been inserted into the card connector.  
         [0070]     Another embodiment of the card connector according to the invention will then be explained with reference to FIGS.  8  to  11 .  FIG. 8  is a perspective view of the card connector viewed from above on the fitting side.  FIG. 9  is a perspective view of a slider and a holder.  FIG. 10  is a front view of the card connector according to the embodiment.  FIGS. 11A  to  11 D are enlarged views of the part A in  FIG. 10  for explaining the states of the slider when memory cards are inserted into respective inserting holes.  
         [0071]     The card connector  10  of this embodiment mainly comprises a case  12 , contacts  13  of many kinds, a slider  120 , and a holder  118 .  
         [0072]     First, the case  12  will be explained. The case  12  is formed with a required number of inserting holes  122  for inserting memory cards  50 . In this embodiment, the case has a construction enabling five memory cards  50  to be inserted. The shapes and sizes of the inserting holes  122  may be designed commensurate with those of the respective memory cards  50 . The kinds of the memory cards  50  to be inserted into the inserting holes  122  in this embodiment will be explained. Among these five inserting holes  122 , four inserting holes  221 ,  223 ,  224  and  225  are arranged substantially side by side and one above the other and the remaining one inserting hole  222  is arranged below and at an intermediate position of the four inserting holes. An SD or MMC card  504  is inserted into the inserting hole  224  arranged uppermost on the left side, and an RS or MMC card  503  is inserted into the inserting hole  223  arranged immediately below the inserting hole  224 . A Memory-Stick Duo card  505  is inserted into the inserting hole  225  arranged uppermost on the right side, and A Mini SD card  501  is inserted into the inserting hole  221  arranged immediately below the inserting hole  225 . A Transflash card  502  is inserted into the inserting hole  222  arranged below and at the intermediate position of the four inserting holes.  
         [0073]     Moreover, the case  12  is formed with inserting grooves  126  in which contacts  13  of plural kinds corresponding to the respective cards  50  are mounted and fixed by press-fitting, hooking (lancing), welding, or the like.  
         [0074]     The case  12  is formed with a fixation hole  124  for fixing the holder  118  therein. The position of the fixation hole  124  may be suitably designed in consideration of functions of the holder  118  described later, the strength of the case  12 , the miniaturization of the connector  10  and the like. In the present embodiment, the fixation hole  124  is provided substantially at the intermediate position of the four inserting holes  221 ,  223 ,  224  and  225  arranged side by side and one above the other (substantial at the center of the connector in its longitudinal direction). The size of the fixation hole  124  for the holder  118  may be suitably designed in consideration of the holding force of the holder  118  for the slider  120 .  
         [0075]     The slider  120  will then be explained, which is a subject matter of this embodiment. The slider  120  is injection molded from an electrically insulating plastic material in the conventional manner. The material for the slider  120  is suitably selected in consideration of dimensional stability, workability, manufacturing cost and the like. In general, preferred materials from which to form the slider  120  include polybutylene terephthalate (PBT), polyamide (66 PA or 46 PA), liquid crystal polymer (LCP), polycarbonate (PC) and the like and combinations thereof. Moreover, the slider may be formed of a metal, insofar as it fulfils the requirements for exhibiting the functions of the slider. In that case, preferred metals are substantially the same as those for the holder.  
         [0076]     The slider  120  is substantially rectangular, and formed with an elongate inserting aperture  128  substantially at the center in the width direction. With this elongate inserting aperture  128 , the slider  120  is movable in its longitudinal direction (in the direction of the thickness of the connector). The holder  118  is inserted in the inserting aperture  128  and in that state the slider  120  is movable relative to the holder  120  fixed in the case  12 . The shape and size of the inserting aperture  128  need only be sufficient to permit the holder  118  to be inserted and the slider  120  to be movable, and may be suitably designed in consideration of such functions and strengths and the like. In the present embodiment, the inserting aperture  128  is 0.1 to 0.3 mm larger than the holder  118 .  
         [0077]     The slider  120  is formed with anchoring portions  133  at peripheries of the inserting aperture  128 , which are adapted to engage fixation pieces  134  of the holder  118  as shown in  FIG. 9 . The shape and size of the anchoring portions  133  adapted to engage the fixation pieces  134  may be suitably designed such that the slider  120  is movable and the fixation pieces  134  do not extend from the slider  120 .  
         [0078]     The slider  120  is provided with required numbers of recess  130  and protrusion  132 , and the combination of these recesses  130  and protrusion  132  forms parts of the inserting holes  122  of the case  12 . In other words, in this embodiment, the slider  120  is provided with four recesses  130  and one protrusion  132 , and four recesses  130  each form part of the inserting hole  221 ,  223 ,  224  and  225  arranged side by side and one above the other, and the one protrusion  132  forms part of the inserting hole  222  arranged below and at an intermediate position of the four inserting holes. The sizes of the recesses  130  and the protrusion  132  may be suitably designed such that when one memory card  50  is inserted into one inserting hole, the slider  120  is moved, with the result that the other recesses and protrusion partly extend into other inserting holes into which any memory card is not yet inserted, thereby preventing other memory card from being inserted into these inserting holes.  
         [0079]     The holder will then be explained, which is another subject matter of the embodiment. The holder  118  is made of a metal and formed by the press-working in the conventional manner. Preferred metals from which to form the holder include brass, beryllium copper, phosphor bronze and the like to fulfil the requirements imposed thereon, such as dimensional stability, formability and the like. An electrically insulating plastic material may be used for the holder insofar as it fulfils the requirements for exhibiting the function of the holder described below. In that case, preferred plastic materials are substantially the same as those for the slider.  
         [0080]     The holder  118  is substantially plate-shaped and comprises a fixation portion adapted to be fixed in the fixation hole  124  of the case  12  and the fixation pieces  134  movably holding the slider  120  and adapted to engage the slider  120 . The holder  118  is fixed to the case  12  by press-fitting or hooking. The holder  118  has a function movably holding the slider  120 .  
         [0081]     In order to hold the slider  120  movably, the holder  118  is provided at its front end with three fixation pieces  134  which are formed by dividing the front end of the holder into three pieces and bending the pieces alternately in opposite directions. The slider  120  is movably held on the case by the engagement of the fixation pieces  134  with the slider  120 . The shape, size and number of the fixation pieces  134  may be suitably designed such that the fixation pieces  134  can engage the slider  120  and the slider  120  is movably held on the case  12 . In this embodiment, the front end of the holder  118  is divided into the three fixation pieces  134  in consideration of stability of movement.  
         [0082]     The plurality of the contacts  13  will then be explained. The contacts  13  each include a contact portion adapted to contact the connection portion of a memory card  50 , a fixed portion to be fixed to the case  12 , and a connection portion to be connected to a board or substrate. As the case  12  has a plurality of inserting holes  122 , among the plurality of contacts  13 , MiniSD card contacts  141 , Transflash card contacts  142 , RS or MMC card contacts  143 , SD or MMC card contacts  144 , and Memory-Stick Duo card contacts  145  are fixed at predetermined positions. The connection portions of the respective contacts  141 ,  142 ,  143 ,  144  and  145  may be suitably designed in consideration of the circuit design of a substrate, occupied areas, the size and design of the connector  10 . In the illustrated embodiment, the connection portions of the SD or MMC card contacts  144  and the Memory-Stick Duo card contacts  145  are arranged on the opposite side of the entry of the inserting hole  122 , while the connection portions of the MiniSD card contacts  141 , the Transflash card contacts  142 , and the RS or MMC card contacts  143  are arranged on the side of the entry of the inserting holes  122 .  
         [0083]     Moreover, the contact portions of the contacts  141 ,  142 ,  143 ,  144  and  145  each extend into the respective inserting hole so as to be able to contact a memory card  50  inserted in the inserting hole  122 . The positions of the contact portions of the contacts are each designed in consideration of the position of the connection portion of the memory card  50  to be inserted, while the extending heights of the contacts are each suitably designed in consideration of contact pressure with a memory card  50 .  
         [0084]     Finally, functions of the slider  120  will be explained with reference to  FIGS. 11A  to  11 E. First, when an SD or MMC card  504  is inserted into the inserting hole  224  arranged uppermost on the left side as shown in  FIG. 11A , the SD or MMC card  504  is also inserted into the recess  130  of the slider  120  forming the part of the inserting hole  224  arranged uppermost on the left side so that the slider  120  is moved upward or downward, and the other recesses  130  and the protrusion  132  extend into the other inserting holes  221 ,  222 ,  223  and  225 .  
         [0085]     Next, when an RS or MMC card  503  is inserted into the inserting hole  223  immediately under the inserting hole  224  arranged uppermost on the left side as shown in  FIG. 11B , the RS or MMC card  503  is also inserted into the recess  130  forming the part of the inserting hole  223  so that the slider  120  is moved upward or downward, and the other recesses  130  and the protrusions  132  extend into the other inserting holes  221 ,  222 ,  224  and  225 .  
         [0086]     Next, when a Memory-Stick Duo card  505  is inserted into the inserting hole  225  arranged uppermost on the right side as shown in  FIG. 11C , the Memory-Stick Duo card  505  is also inserted into the recess  30  forming the part of the inserting hole  225  so that the slider  120  is moved upward or downward, and the other recesses  130  and the protrusion  132  extend into the other inserting holes  221 ,  222 ,  223  and  224 .  
         [0087]     Next, when a Mini SD card  501  is inserted into the inserting hole  221  immediately under the inserting hole  225  arranged uppermost on the right side as shown in  FIG. 11D , the Mini SD card  501  is also inserted into the recess  30  forming the part of the inserting hole  221  so that the slider  120  is moved upward or downward, and the other recesses  130  and the protrusions  132  extend into the other inserting holes  222 ,  223 ,  224  and  225 .  
         [0088]     Finally, when a Transflash card  502  is inserted into the inserting hole  222  arranged in the lowermost and at the intermediate position of the four upper inserting holes, the protrusion  132  of the slider  120  is moved upward by the Transflash card  502  inserted in the inserting hole  222  so that the recesses  130  extend into the other inserting holes  221 ,  223 ,  224  and  225 .  
         [0089]     While the card connector  10  including the case  12  provided with five inserting holes  122  for memory cards are explained and illustrated in this embodiment, it will be apparent that the number of the inserting holes is not limited. With the combination of plural members having the constructions of the slider  120  and the holder  118  described above, it is possible to design suitably a card connector capable of preventing a memory card from being inserted after one memory card  50  has been inserted into the card connector.  
         [0090]     The present invention is applicable to card connectors for use in a wide variety of electric and electronic appliances such as a printer, card reader and the like and particularly to a card connector which must be capable of preventing the insertion of more than one memory card.  
         [0091]     While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details can be made therein without departing from the spirit and scope of the invention.