Patent Publication Number: US-6669493-B2

Title: Card connector unit provided with first accomodating position and second accomodating position

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a card connector unit for accommodating a small memory card or what is known as an SD card and connecting a group of external connection terminals provided on this card to an electronic circuit provided in an electronic device such as a personal computer (PC), and more particularly to a card connector unit compatible with cards extended in length to be adaptable to multiple functions. 
     2. Description of the Related Art 
     Cards that can be freely inserted or withdrawn from an electronic device such as a PC or an electronic camera and permits writing or reading of information (hereinafter known as SD cards) are already known according to the prior art. This kind of card is substantially rectangularly shaped, and at one end of one side are arrayed a plurality of external connection terminals. The electronic device to accommodate such SD cards is provided with a circuit board on which are mounted required electronic circuits and a card connector unit for connecting the group of external connection terminals mounted on the SD card to the electronic circuits. 
     Such a card connector unit is provided with a housing having an accommodating space into which the SD card is to be inserted through an inlet, a plurality of terminal pieces fixed to this housing and exposed in the accommodating space, and a discharging mechanism for discharging an accommodated SD card. 
     The housing is usually configured by combining a frame made of an insulating material and a cover made of a metallic material or an insulating material, and an SD card accommodating space is formed between the frame and the cover. Each terminal piece is provided with a contact exposed within the accommodating space to be able to come into contact with the connection terminals of an SD card and a soldering portion to be soldered onto an electronic circuit provided in an electronic apparatus such as a personal computer (PC). It is so designed that, when an SD card inserted into the accommodating space is placed in a prescribed position, the group of its external connection terminals come into contact with the contact of each terminal piece. 
     A discharging mechanism of a known configuration, for instance, comprises a slider capable of reciprocating in engagement with an SD card, coil springs elastically energizing this slider in the direction of discharging the card, and engaging pins guided along a heart-shaped cam groove. When the operator presses with fingers the SD card placed in a prescribed position, on the edge toward him or her (rear edge), this configuration, by causing the slider and the engaging pin to work in conjunction, enables the card to move together with the slider outward to the operator&#39;s side to be readily discharged. Another known configuration is such that, by operating a member for discharging action to release the SD card engaged in a prescribed position, the card can be discharged. 
     Incidentally, in connection with a recently rising call for the usability of an SD card not only as a mere recording medium but also as a communication device by providing it with a transmitter/receiver circuit or the like, the emergence of a new type SD card extended in length but the same in terminal specification as the conventional SD card is expected. A well conceivable use of such a new type SD card is, for instance, to arrange an antenna circuit for short range radio communication toward the rear end of an SD card of an extended length, keep the SD card in only a shallowly inserted position in the connector unit only when this antenna circuit is to be used, and insert the SD card deep into the connector unit when the antenna is not to be used. 
     However, since the conventional card connector unit does not have a structure to accommodate such a long SD card, it may allow the SD card to be inserted to a prescribed extent and electrically connected, but, for instance when the antenna circuit is not to be used, it is impossible to insert the SD card deeply and keep it there. Thus, if a card connector unit for a conventional card is to be adapted to a longer-than-usual SD card, the SD card will have to kept substantially protruding outward from the inlet of the accommodating space of the housing, not only will the appearance be awkward but also it will result in serious inconvenience of use because the electronic apparatus such as a laptop PC will have to be carried with the SD card kept inserted in the connector unit. 
     SUMMARY OF THE INVENTION 
     The present invention has been attempted to obviate these disadvantages of the prior art, and to provide a more convenient card connector unit allowing selective placement of an SD card of an extended length in any of positions differing in insertion depth. 
     In order to achieve the object noted above, a card connector unit according to the invention has a configuration comprising a housing having an accommodating space into which a card provided with a group of external connection terminals (SD card) is inserted from a side of an inlet and permitting the card to be selectively placed within the accommodating space in a first accommodating position in which an insertion depth is smaller or a second accommodating position in which an insertion depth is greater; terminal sections fixed to the housing to be exposed in the accommodating space and being in contact with the group of external connection terminals at least when the card is in the first accommodating position; and a shifting mechanism for driving the card inserted in the accommodating space to be shifted at least from the second accommodating position to the first accommodating position. 
     Since a connector unit of such a configuration not only allows a shorter SD card to be inserted and placed in the first accommodating position but also a longer SD card to be placed either in the first accommodating position or the second accommodating position, if the longer SD card is placed in the first accommodating position, for instance an antenna circuit built into that SD card can be exposed to enable it to be used as a communication device. Or if the longer SD card is inserted deep into the second accommodating position, it can be used as a recording medium or stowed in a state convenient for carrying. If the longer SD card placed in the first accommodating position is pressed by the operator deeper inward with fingers, the SD card can be easily shifted to the second accommodating position, and the longer SD card placed in the second accommodating position can be shifted to the first accommodating position using the shifting mechanism. Thus the longer SD card can be easily shifted from one accommodating position to the other. 
     Further in the above-described configuration according to the invention, the shifting mechanism may be provided with sliding members capable of reciprocating along an inserting/discharging direction of the card while being kept engaged with the card, engaging pins shifting along a heart-shaped cam groove along with shifting of the sliding members, and energizing members for elastically energizing the sliding members in a discharging direction of the card. If it is so arranged that, when the card is placed in the second accommodating position, the engaging pins may be engaged with pin engaging portions of the heart-shaped cam groove to inhibit shifting of the sliding members and, by pressing the card deeper in the accommodating space in such a state and thereby disengaging the engaging pins from the pin engaging portions, the card can be shifted in the discharging direction from the second accommodating position via the sliding members, the operator can press the SD card placed in the first accommodating position further inward to a prescribed extent to engage the engaging pins with the pin engaging portions of the heart-shaped cam groove to bring to halt the SD card in the second accommodating position. Or the operator can press the SD card placed in the second accommodating position to disengage the engaging pins from the pin engaging portions to direct the SD card to the first accommodating position with the elastic force of the energizing members. Therefore the longer SD card can be easily shifted from one accommodating position to the other. 
     If, in addition to this configuration, there is provided a discharging mechanism capable of discharging the card placed in the first accommodating position, when the SD card placed in the second accommodating position is to be discharged, there will be no need to rely only on the elasticity of the energizing members of the shifting mechanism and, if the energizing members are coil springs, the extent of their extension and contraction can be restrained to elongate their service lives. Nor will there be the phenomenon of an increase in reaction force with the elongation of the insertion depth of the SD card, resulting in improved operating ease. 
     In this case, the configuration may as well be such that the discharging mechanism is provided with a first sliding member capable of reciprocating along the inserting/discharging direction of the SD card; an engaging arm rotatably pivoted on this first sliding member and permitting engagement with the fore edge of the SD card; a first engaging pin shifting along a prescribed guide groove along with the shifting of the first sliding member, and a first energizing member for elastically energizing the first sliding member in the card discharging direction; and there may be further provided a rotation regulator for regulating outward rotation of the engaging arm when an inserted position of the card has not reached the first accommodating position, and a rotation permitting section for permitting outward rotation of the engaging arm and setting aside the engaging arm on the way of shifting of the card from the first accommodating position to the second accommodating position. Then, as the engaging arm steps aside into the rotation permitting section at a stage where the SD card is inserted midway between the first accommodating position and the second accommodating position, there is no need to set back the first sliding member any further, and the SD card can be pressed further inward while moving back the sliding members of the sliding member to bring it to the second accommodating position. Therefore, if the first energizing member is a coil spring for instance, the extent of its extension and contraction can be restrained to elongate its service life. 
     Or the guide groove of the discharging mechanism may as well be provided with a return path for guiding the first engaging pin in a process of shifting the SD card from the second accommodating position to the first accommodating position, a return pin engaging portion capable of holding the SD card in the first accommodating position by engaging the first engaging pin having passed the return path, and a proceeding path extending inward from the return pin engaging portion to enable the SD card to shift from the first accommodating position to the second accommodating position. Then, by engaging the first engaging pin with the return pin engaging portion, the first sliding member can be inhibited from shifting and the SD card can be held in the first accommodating position. Then, if the SD card is pressed further inward from the first accommodating position, the first engaging pin will be disengaged from the return pin engaging portion and shift further inward on the proceeding path, or if, conversely, the SD card is pressed outward from the second accommodating position outward by the shifting mechanism, the first engaging pin will shift outward to be engaged with the return pin engaging portion. Therefore, without having to using a complex configuration, the SD card can be easily and smoothly shifted between the first accommodating position and the second accommodating position. 
     To add, where the SD card placed in the first accommodating position is to be discharged with an operating member, the guide groove may be provided with a discharging path for guiding the first engaging pin in a process of shifting the card outward from the first accommodating position and an operating member for discharging the card placed in the first accommodating position, and the first engaging pin can be shifted from the return pin engaging portion to the discharging path by manipulating the operating member to press in the first engaging pin. Then the discharging can be simplified and made reliable without requiring a complex configuration. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a plan of a card connector unit in a mode of carrying out the present invention; 
     FIG. 2 shows a plan of the housing of the card connector unit; 
     FIG. 3 shows a plan of the terminal section of the card connector unit; 
     FIG. 4 illustrates a guide groove provided in a first discharging mechanism of the card connector unit; 
     FIG. 5 illustrates a guide groove provided in a second discharging mechanism of the card connector unit; 
     FIG. 6 illustrates the operation of the connector unit in which a longer SD card is inserted; 
     FIG. 7 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 8 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 9 illustrates the operation of the connector unit in which the longer SD card is inserted: 
     FIG. 10 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 11 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 12 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 13 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 14 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 15 illustrates the operation of the connector unit in which the longer SD card is inserted; 
     FIG. 16 illustrates the operation of the connector unit in which a shorter SD card is inserted; 
     FIG. 17 illustrates the operation of the connector unit in which the shorter SD card is inserted; 
     FIG. 18 shows a plan of a card connector unit in another mode of carrying out the present invention; 
     FIG. 19 illustrates the operation of the card connector unit; and 
     FIG. 20 illustrates the operation of the card connector unit. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     To describe a mode of carrying out the present invention with reference to accompanying drawings, FIG. 1 shows a plan of a card connector unit in the mode of carrying out the invention with the illustration of its cover dispensed with; FIG. 2 shows a plan of the housing of the card connector unit; FIG. 3, a plan of the terminal section of the card connector unit; FIG. 4 illustrates a guide groove provided in a first discharging mechanism of the card connector unit; and FIG. 5, a guide groove provided in a second discharging mechanism of the card connector unit. 
     The card connector unit illustrated in these drawings is intended for accommodating an SD card into the electronic device such as a PC which it is built into. A group of external connection terminals of an SD card placed in a prescribed position can be connected to an electronic circuit provided in an electronic apparatus per se. This card connector unit is configured to accommodate not only a shorter SD card but also a longer SD card. 
     To describe the specific configuration, this card Connector unit mainly consists of a housing composed by combining a frame  1  made of an insulating material and a cover (not shown) made of a metallic material, a plurality of metal sheet-made terminal units  2  constituted by linking terminal pieces  3  and  4  by a linking portion  5  and fixed to the frame  1  by an insert formation technique, a first discharging mechanism  6  provided on one side of the frame  1  and a second discharging mechanism  7  provided on the other side of the frame  1 . 
     Between the frame  1  and the cover of the housing, there is formed an accommodating space  8  into which an SD card is to be inserted from the inlet  8   a  side. Also, as shown in FIG. 2, on one side of the frame  1  are formed guide grooves  9  constituting a part of the first discharging mechanism  6 , a regulating wall  10  and a cutout  11 , and on the other side of the frame  1  is formed a heart-shaped cam groove  12  constituting a part of the second discharging mechanism  7 . Further, in the frame  1  is formed, near the inlet  8   a , a peephole  13  through which ends of the terminal units  2  on one side are exposed. 
     The terminal units  2  are arranged in two rows, fore and rear, as shown in FIGS. 1 and 3. A group of terminal pieces  3  exposed near the central part of the accommodating space  8  constitute a first terminal section  30 , and a group of terminal pieces  4  exposed in a deep part of the accommodating space  8  constitutes a second terminal section  40 . Each pair of terminal pieces  3  and  4  of these first and second terminal sections  30  and  40  are arranged on the same straight line in the depthwise (lengthwise) direction of the frame  1 , and linked by the linking portion  5  as described above. Further, the free ends of the terminal pieces  3  and  4  constitute contacts  3   a  and  4   a , respectively, the relative positional relationship among the contacts  3   a  and that among the contacts  4   a  are all set to be equivalent to the relative positional relationship (terminal arrangement) among the grouped external connection terminals of the SD card. At the ends on one side of the terminal units  2  including the paired terminal pieces  3  and  4 , there are provided soldering portions  2   a  as shown in FIG. 3, and the soldering portion  2   a  of each terminal unit  2  protrudes into the peephole  13  of the frame  1 . These soldering portions  2   a  are soldered onto an electronic circuit provided on a circuit board (not shown) of the electronic apparatus per se. 
     Thus, in this card connector unit are set a first accommodating position in which the insertion depth of an SD card is smaller and a second accommodating position in which its insertion depth is greater. If the SD card is inserted to the vicinity of the central part of the accommodating space  8  and placed in the first accommodating position, its group of external connection terminals will come into contact with the Contacts  3   a  of the terminal piece  3 . Or if the SD card is inserted as far as to a deep part of the accommodating space  8  and placed in the second accommodating position, its group of external connection terminals will come into contact with the contacts  4   a  of the terminal piece  4 . 
     The first discharging-mechanism  6  is provided with a first sliding member  14  capable of reciprocating along the inserting/discharging direction of the SD card, an engaging arm  15  rotatably borne by this first sliding member  14  and capable of engaging with the fore edge of the SD card, a first engaging pin  16  moving along the guide groove  9  together with the shifting of the first sliding member  14 , a keep plate  17  for keeping this engaging pin  16  from running off the groove  9 , a first elastic piece  18  capable of engaging with a concave provided on one side edge of the SD card and held by the first sliding member  14 , a second elastic piece  19  capable of engaging with the concave of the SD card and held by the engaging arm  15 , and a first coil spring  20  for elastically energizing the first sliding member  14  in the discharging direction of the card. The regulating wall  10  and the cutout  11  of the frame  1  also are constituent elements of the first discharging mechanism  6 . The regulating wall  10  regulates the outward rotation of the engaging arm  15  when the inserted position of the SD card has not yet reached the first accommodating position. On the other hand, the cutout  11 , on the way of the SD card shifting from the first accommodating position toward the second accommodating position, permits the engaging arm  15  to rotate outward and sets aside the engaging arm  15 . 
     The guide groove  9  is provided with a heart-shaped cam groove  21  having a pin engaging portion  21   a  for engaging the engaging pin  16  to keep the SD card in the first accommodating position, a first guide groove  22  continuous from the heart-shaped cam groove  21  upstream from the pin engaging portion  21   a  and extending inward, a second guide groove  23  continuous from the heart-shaped cam groove  21  downstream from the pin engaging portion  21   a  and extending inward, a return path for guiding the progress of the first engaging pin  16  in the process of the shifting of the SD card from the second accommodating position to the first accommodating position, and an extended path  25  continuous from the two guide grooves  21  and  22  and the return path  24  and extending inward. The second guide groove  23  constitutes a proceeding path to enable the SD card to shift from the first accommodating position to the second accommodating position. Within the return path  24  is formed a return pin engaging portion  24   a  for engaging the first engaging pin  16  on the way of shifting along this return path  24  and thereby to hold the SD card in the first accommodating position, and this return path  24  is made continuous to and from the second guide groove  23  downstream from the return pin engaging portion  24   a . When the first engaging pin  16  is engaged by either the pin engaging portion  21   a  or the return pin engaging portion  24   a , as the shifting of the first sliding member  14  is thereby inhibited, the SD card engaged with the first sliding member  14  via the first elastic piece  18  is held in the first accommodating position. 
     The second discharging mechanism  7  is provided with a second sliding member  26  having an engaging portion  26   a  projecting from it and capable of being engaged with the fore edge of the SD card, the sliding member  26  being capable of shifting reciprocatively along the inserting/discharging direction of the SD card, a second engaging pin  27  shifting along the heart-shaped cam groove  12  together with the shifting of this sliding member  26 , a keep plate  28  for keeping this engaging pin  27  from running off the heart-shaped cam groove  12 , and a second coil spring  29  for elastically energizing the second sliding member  26  in the discharging direction of the SD card. In the heart-shaped cam groove  12  is formed a pin engaging portion  12   a . When the SD card is in the second accommodating position, the second engaging pin  27  is engaged by the pin engaging portion  12   a  to obstruct the second sliding member  26  from shifting. At this time, the second elastic piece  19  held by the engaging arm  15  is engaged with the recess of the SD card to hold the SD card in the second accommodating position. 
     Next will be described with reference to FIG.  6  through FIG. 17 the operation of the card connector unit configured as described above. First will be described its actions when a longer SD card  60  than the currently more common shorter SD card  50  is to be used with reference to FIG.  6  through FIG.  15 . 
     Toward the fore edge of the longer SD card  60  in the inserting direction, there are provided a group of external connection terminals  61  that can come into contact with the contacts  3   a  and  4   a  of the terminal pieces  3  and  4 , respectively. On one side edge of this SD card  60  is provided a recess  62  that can engage with the elastic pieces  18  and  19  of the first discharging mechanism  6 . This longer SD card  60  is designed to be equal to the shorter SD card  50  in all respects including the width, the arrangement of the group of external connection terminals  61  and the distance from the fore edge to the recess  62  except that the longer SD card  60  has at its rear end an antenna circuit (not shown). It is desirable, when this antenna circuit is to be used, to place the card in the connector unit in a state in which the rear edge of the card is exposed outside the inlet. 
     FIG. 6 shows a plan of the connector unit in this mode of carrying out the invention in a state immediately after the insertion of the longer SD card  60  is started. When the longer SD card  60  is inserted to the position shown in FIG. 6, the first elastic piece  18  engages with its recess  62 , and the engaging arm  15  comes into contact with the fore edge of the SD card  60 . Therefore, as the operator inserts the SD card  60  deeper, the engaging arm  15  whose outward rotation is regulated by the regulating wall  10  of the frame  1  is pressed inward by the SD card  60 , the first sliding member  14  and the engaging arm  15  are shifted inward by the movement of the SD card  60  and, along with the shifting of the first sliding member  14 , the first engaging pin  16  shifts along the heart-shaped cam groove  21 . 
     When the SD card  60  is pressed in somewhat deeper than its first accommodating position, the first engaging pin  16  shifts from the heart-shaped cam groove  21  to the first guide groove  22  as indicated by arrows in FIG.  7 . Therefore, when the pressing force is removed, the elasticity of the first coil spring  20  presses outward the first sliding member  14  and the engaging arm  15  to enable the first engaging pin  16  to be engaged with the pin engaging portion  21   a . Accordingly, the SD card  60  is held in its first accommodating position, in which the group of external connection terminals  61  are in contact with the contacts  3   a  of the terminal pieces  3 , so that the antenna circuit exposed toward the operator is placed in a usable state. 
     When the SD card  60  thereby placed in its first accommodating position is to be discharged, the SD card  60  in the state shown in FIG. 7 can be pressed slightly inward. As this causes the first engaging pin  16  to be disengaged from the pin engaging portion  21   a  to shift downstream in the heart-shaped cam groove  21  as indicated by arrows in FIG. 6, the SD card  60  is pressed back to its discharging position by the first sliding member  14  and the engaging arm  15  which are shifted outward by the elasticity of the first coil spring  20 . Thus, the operator can discharge the SD card  60  held in its first accommodating position by a simple one-push action. 
     Or when the SD card  60  held in its first accommodating position to use the antenna circuit is to be shifted to its second accommodating position, the operator can press inward the SD card  60  in the state of FIG.  7 . Then, along with the shifting of the first sliding member  14 , the first engaging pin  16  shifts from the heart-shaped cam groove  21  to the extended path  25  via the second guide groove  23  as indicated by arrows in FIG.  8 . At the time when the SD card  60  has been inserted to the position shown in FIG. 8, the engaging arm  15 , being pressed by the SD card  60 , rotates outward to step aside into the cutout  11  of the frame  1 , and accordingly the inward shifting of the engaging arm  15  is regulated. For this reason, even though the SD card  60  is pressed further inward, the first sliding member  14  remains unmoved, and the first elastic piece  18  is disengaged from the recess  62  of the SD card  60 . However, as the fore edge of the SD card  60  is pressing inward the engaging portion  26   a  of the second sliding member  26  at this point of time, the second sliding member  26  follows the further inward shifting of the SD card  60 , and the second engaging pin  27  shifts along the heart-shaped cam groove  12 . 
     Then, by pressing the SD card  60  farther inward than its second accommodating position, the second engaging pin  27  shifts in the heart-shaped cam groove  12  as indicated by arrows in FIG.  9 . Therefore, when the pressing force is removed, the elasticity of the second coil spring  29  presses outward the second sliding member  26  to enable the second engaging pin  27  to be engaged with the pin engaging portion  12   a . Accordingly, the SD card  60  is kept in its second accommodating position in which the group of external connection terminals  61  are in contact with the contacts  4   a  of the terminal pieces  4 , and is in a stowed state in which it does not protrude substantially outward. Incidentally, when the SD card  60  is placed in its second accommodating position, the second elastic piece  19  is in the recess  62  in the SD card  60  to be engaged with it. 
     Or, when the SD card  60  held in its second accommodating position is to be shifted to the first accommodating position to use the antenna circuit, the SD card  60  in the state of FIG. 9 can be pressed further inward. As this causes the second engaging pin  27  to be disengaged from the pin engaging portion  12   a , and shifts downstream in the heart-shaped cam groove  12  as indicated by arrows in FIG. 10, the SD card  60  is pressed back to its first accommodating position in the sequence shown in FIGS. 11 and 12 by the engaging portion  26   a  of the second sliding member  26  shifted outward by the elasticity of the second coil spring  29 . FIG. 11 illustrates a state in which the engaging arm  15 , until then kept aside in the cutout  11 , rotates inward and the first sliding member  14  begins shifting outward, where the first engaging pin  16  is shifting from the extended path  25  to the return path  24 . FIG. 12 shows a state in which the first engaging pin  16  is engaged by the return pin engaging portion  24   a  of the return path  24 , and the SD card  60  has returned to its first accommodating position. Thus, the operator can shift the SD card  60 , held in its second accommodating position, to the first accommodating position by a simple one-push action to set the antenna circuit in a usable state. However, as is evident from FIG.  7  through FIG. 12, the moving path of the first engaging pin  16  differs with the shifting direction of the SD card  60 , i.e. whether it is shifting from the first accommodating position to the second accommodating position or vice versa. 
     When the SD card  60 , after it has thus been shifted from the second accommodating position to the first accommodating position to place the antenna circuit in a usable state, is to be shifted to the second accommodating position again, the operator has only to press the SD card  60  deeper inward. As this causes the first engaging pin  16  engaged with the return pin engaging portion  24   a  to shift along the second guide groove  23 , which is its moving path, to the extended path  25  as shown in FIGS. 13A through 13C, continuing to press the SD card  60  inward will resulting in the state of FIG. 9 via the state of FIG.  8 . When the SD card  60  having shifted from the second accommodating position to the first accommodating position to place the antenna circuit in a usable state is to be discharged, the operator can press the SD card  60  slightly inward and then remove the force acting on it. As this results in the pressing back, by the elasticity of the first coil spring  20 , of the first sliding member  14  and the engaging arm  15  at the point of time when the first engaging pin  16  which has been engaged with the return pin engaging portion  24   a  has shifted midway along the second guide groove  23  as shown in FIGS. 14A through 14C, the first engaging pin  16  proceeds downstream in the heart-shaped cam groove  21  to discharge the SD card  60 . To add, the part in which the first engaging pin  16  which has been engaged with the return pin engaging portion  24   a  is guided from the second guide groove  23  to downstream in the heart-shaped cam groove  21  in the process of shifting outward the SD card  60  from its first accommodating position constitutes the discharging path. 
     When it is desired to house the inserted SD card  60  immediately, the SD card  60  can as well be placed directly in the second accommodating position, the first accommodating position being skipped. Thus, as the inserted SD card  60  is pressed deep inward, the first engaging pin  16  shifts from the heart-shaped cam groove  21  to the extended path  25  via the first guide groove  22  as indicated by arrows in FIG. 15, continuing to press the SD card  60  inward will result in shifting to the state of FIG. 8 via that of FIG.  9 . 
     Next, actions to use the shorter SD card  50  with this card connector unit will be described with reference to FIGS. 16 and 17. FIG. 16 shows a plan of the unit immediately after the insertion of the shorter SD card  50 , and, FIG. 17, the plan of the unit in which the SD card  50  is placed in the first accommodating position. 
     As is evident from these drawings, the shorter SD card  50  cannot be inserted so far inside as to the second accommodating position, but can only be placed in the-first accommodating position. Further, as described above, the shorter SD card  50  and the longer SD card  60  are equal in the width, the arrangement of the group of external connection terminals and other respects. Therefore, exactly the same actions as described with reference to FIGS. 6 and 7 can be applied, i.e. the insertion of the longer SD card  60  into the first accommodating position and the discharging of the longer SD card  60 . For instance, if the operator presses in the shorter SD card  50  in the state shown in FIG. 16, the first engaging pin  16  will shift to the first guide groove  22  through the heart-shaped cam groove  21  and, when the pressing force is removed, the SD card  50  can be placed in the first accommodating position because the engaging pin  16  then returns to the heart-shaped cam groove  21  to be engaged with the pin engaging portion  21   a . Or if the operator presses in the SD card  50  slightly in the state of FIG. 17, as the first engaging pin  16  engaged with the pin engaging portion  21   a  will shift to the second guide groove  23 , the engaging pin  16  will proceed downstream in the heart-shaped cam groove  21  to discharge the SD card  50  when the pressing force is removed. 
     To add, in this mode of implementing the invention, as shown in FIG.  17  and FIG. 9, these first and second accommodating positions are so set as to equalize the outward projecting length L 1  of the rear edge of the shorter the SD card  50  placed in the first accommodating position and the outward projecting length L 2  of the rear edge of the longer SD card  60  placed in the second accommodating position. 
     Thus in this mode of implementation, not only can the shorter the SD card  50  be used in the first accommodating position, but also can the longer SD card  60  be used in the second accommodating position. As even the longer SD card  60  can be stowed if it is placed in the second accommodating position, there is no fear of adversely affecting the appearance or the portability of the unit. 
     Also, as this mode of implementation allows the longer SD card  60  to easily and smoothly reciprocate between the first accommodating position and the second accommodating position by providing the first discharging mechanism  6 , having the prescribed guide groove  9 , that can discharge the SD card placed in the first accommodating position and the second discharging mechanism  7  that can shift the SD card placed in the second accommodating position toward the first accommodating position, it readily provides a practical way of use in which, for instance, the SD card  60  is placed in the first accommodating position only when the antenna circuit is to be used and is stowed in the second accommodating position at other times. Moreover, as there are provided the first coil spring  20  to give a discharging force to the SD card placed in the first accommodating position and the second coil spring  29  to give a discharging force to the SD card placed in the second accommodating position, it is possible to press in the SD card with a stable force all the time and thereby to extend the service lives of the coil springs. 
     Another mode of implementing the present invention will now be described with reference to FIG.  18  through FIG.  20 . The embodiment of the invention in this mode is designed to require the operator to press an operating member  70  for discharging use only when the longer SD card  60  having been shifted from the second accommodating position to the first accommodating position is to be discharged, and differs from the embodiment in the earlier described mode in the shape of the guide groove  9  for guiding the first engaging pin  16 . 
     Thus, the guide groove  9  in this mode of implementation is provided with the heart-shaped cam groove  21  having the pin engaging portion  21  for engaging the first engaging pin  16  to hold the SD card in the first accommodating position, the guide groove  23  continuous to and from the heart-shaped cam groove  21  on the downstream side of the pin engaging portion  21 , the return path  24  for guiding the direction of the first engaging pin  16  in the shifting process of the SD card from the second accommodating position to the first accommodating position, and the extended path  25  continuous to and from the guide groove  23  and the return path  24 . Within the return path  24 , there is formed the return pin engaging portion  24   a  for engaging the first engaging pin  16  shifting along this return path  24  to hold the SD card in the first accommodating position. However, unlike in the foregoing mode of implementation, the return path  24  and the guide groove  23  constitute no circulatory path, and the return path  24  also serves as a path for enabling the SD card to shift from the first accommodating position to the second accommodating position. Therefore, in order to shift the first engaging pin  16  from the return pin engaging portion  24   a  to the guide groove  23 , the operating member  70  has to be manipulated to push up the engaging pin  16  to the guide groove  23 . 
     FIG. 19 illustrates a state in which the longer SD card  60  having shifted from the second accommodating position is held in the first accommodating position. When the operator presses in the operating member  70  in this state, as the first engaging pin  16  engaged with the return pin engaging portion  24   a  is pushed up toward the guide groove  23 , the engaging pin  16  proceeds downstream in the heart-shaped cam groove  21  to enable the SD card  60  to be discharged as illustrated in FIG.  20 . However, if in the state of FIG. 19 the operator presses in the SD card  60 , the first engaging pin  16  engaged with the return pin engaging portion  24   a  will proceed inward along the return path  24  only to reach the extended path  25 , and therefore the SD card  60  cannot be discharged even though it can be placed in the second accommodating position Thus in this mode of implementation, the operating member  70  is used only when the longer SD card  60  is to be discharged, the SD card is directly pressed as in the foregoing mode of implementation when the accommodating position of the longer SD card  60  is to be altered or the shorter SD card  50  is to be inserted or discharged. 
     The present invention, implemented in the modes described above, provides the following advantages. 
     As the card connector unit permits not only a shorter SD card to be inserted and placed in the first accommodating position but also a longer SD card to be placed either in the first accommodating position or in the second accommodating position, it is possible, for instance, to insert the longer SD card deep inward and stow it in the second accommodating position when the unit is to be carried by the user, and to bring the SD card more outward with the shifting mechanism and to place it in the first accommodating position when the antenna circuit or the like is to be used, resulting in enhanced convenience of use. 
     If the shifting mechanism is provided with a sliding member, a heart-shaped cam groove, engaging pins, energizing members and the like, the longer SD card can be easily and smoothly shifted from one accommodating position to the other. 
     If there is provided a discharging mechanism that can discharge an SD card in the first accommodating position, there will be no need to use the elasticity of the energizing members of the shifting mechanism when the SD card in the second accommodating position is to be discharged, and therefore the energizing member, if it is a coil spring, can be extended in service life by restraining the extent of its extension and contraction. Nor will there be the phenomenon of an increase in reaction force with the elongation of the insertion depth, resulting in improved operating ease.