Abstract:
An adapter electrically connects an integrated circuit mini-card in a main electronic integrated circuit memory card connector having greater space requirement than the mini-card. The mini-card has surface contact strips and the adapter includes a main body capable of being connected to the main connector and a housing for receiving the mini-card at the surface of the main body. The housing includes inside bond pads for connection to the electric contacts of the mini-card. A mobile cover is capable of taking up a position wherein it closes at least partly the housing while maintaining the mini-card in electrically connecting position in the housing and stiffening the structure of the adapter.

Description:
This disclosure is based upon French Application No. 02/15336 filed Dec. 5, 2002, and International Application No. PCT/FR2003/003533, filed Dec. 1, 2003, the contents of which are incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention concerns an adaptor for the electrical connection of an integrated-circuit mini-card in a connector. 
     The present invention concerns more particularly an adaptor for the electrical connection of an integrated-circuit mini-card in a main connector for an electronic integrated-circuit memory card with contact with a greater size than the mini-card, the mini-card comprising surface contact strips and the said adaptor comprising a main body able to be connected to the main connector and a housing receiving the mini-card emerging on the surface of the main body and comprising, inside, pads for connection to the electrical contacts of the mini-card. 
     Currently, more and more appliances are using electronic memory cards of a standard type, which allow in particular a large amount of data storage in order thus to constitute a removable data medium which overall has small dimensions and a large storage capacity. Several example embodiments of such a type of memory card are known, whose dimensions are smaller and smaller and whose storage capacities are larger and larger. 
     This is particularly the case with the so-called “MMC” (MultiMediaCard) sold by the company SANDISK, where the dimensions of its body containing the integrated circuits and the positioning of its conductive contact areas are defined precisely by its manufacturer and by an association of users in order to have a standard-type definition of such a card. This definition is for example the subject of the publication “MultiMediaCard System Specification Version 2.11 Official Release @ June 1999 MMC”. 
     Another memory card with a large storage capacity, referred to as an “SD” (Secure Digital) card, is sold by SANDISK. 
     All the characteristics and performances of the SD cards are defined by the documents issued by the SDC (SD Card Association), whose address is 53 Muckelemi St, P.O. Box 189, San Juan Baustista, Calif. 95045-0189, USA. 
     The overall dimensions of the MMC and SD cards are identical, with the exception of the thickness of the SD card, which is increased. 
     Another memory card known as an “MS” (Memory Stick) card is sold by SONY. 
     All the characteristics and performances of the MS card are defined in the document published by Sony Corporation and entitled “Memory Stick Standard—Memory Stick Duo Format Specifications ver. 1.0—August 2001”. 
     These various memory card formats all have the same rectangular shape, with longitudinal conductive areas which are arranged on or in one of the main faces parallel to and close to a transverse edge of the card. 
     It has been noted that the external size of each of these memory card formats is greater than the external size of a standard integrated-circuit mini-card of the mini-SIM type (SIM signifying “Subscriber Identification Module”), which is a small card currently used in the radiotelephony field as a data storage medium, in particular for data identifying the user of the mini-card. 
     SUMMARY OF THE INVENTION 
     The invention aims to propose an adaptor for connecting a mini-card in a connector designed to receive a standard memory card with high storage capacity. 
     To this end, the invention proposes an adaptor for the electrical connection of an integrated-circuit mini-card in a main connector for an electronic integrated-circuit memory card with contact with a size greater than the mini-card, the mini-card comprising surface contact strips and the said adaptor comprising a main body able to be connected to the main connector and a housing receiving the mini-card emerging on the surface of the main body and comprising, inside, pads for connection to the electrical contacts of the mini-card, characterised in that it comprises a movable cover which is able to occupy a position in which it at least partially closes off the housing whilst holding the mini-card in the electrical connection position in the housing and stiffening the overall structure of the adaptor. 
     According to other characteristics of the invention:
         the cover is mounted so as to slide longitudinally on the main body;   the cover overall has the form of a profiled section in an inverted U comprising a transverse main plate and two longitudinal lateral wings, and each lateral wing is provided, at its free end, with a return which comes into abutment against a portion of the opposite face of the body;   the cover comprises a transverse main plate and the cover is mounted on the body by fitting in;   the main plate of the cover comprises means, such as embossings, for increasing its longitudinal and/or transverse rigidity;   the cover is produced from metal;   the top main face of the body is provided with parallel longitudinal conductive areas and the body is produced from a plastics material which is moulded around conductive blades, each blade comprising a first section electrically connected to a conductive area and a second section forming an associated connecting pad;   the first section of each conductive blade constitutes a conductive area;   the connecting wall of the housing, which is provided with the connecting pads, comprises, opposite contact strips on the mini-card, a cavity in which the second end section of each blade extends roughly longitudinally, forming a protrusion projecting inside the housing so that, when a mini-card is present in the housing, each connecting pad is forced elastically towards the associated contact strip in order to provide the electrical connection between them by contact;   each connecting pad is arranged in line with a vertical connecting well which extends between the connecting wall of the housing, which is provided with the connecting pads, and a main face of the body, which contains a conductive material, so that each connecting well electrically connects a connecting pad to an associated conductive track, which is arranged on the said main face of the body, and each conductive track is electrically connected to a longitudinal conductive area associated with the connecting pad and arranged on the top main face of the body;   the conductive tracks are arranged on the bottom main face of the body, and each conductive area is arranged in line with a vertical connecting well which extends between the top main face and the bottom main face of the body, and which contains a conductive material, so that each conductive area is electrically connected to the associated conductive track through a connecting well;   the body comprises several vertically superimposed layers, and a series of conductive tracks is arranged between two layers;   each conductive pad is produced by the deposition of a film of conductive elastic material, for example silicone containing metallic particles, which forms a protrusion, protruding inside the housing, so as to guarantee the electrical connection by contact between each connecting pad and the associated contact strip on the mini-card, despite any lack of co-evenness between the connecting face of the housing and the opposite face of the mini-card;   each connecting pad is formed by a metallic dome attached to the connecting wall;   the body comprises positive location means for guaranteeing the correct positioning of the mini-card in the housing;   the mini-card is a standard card of the mini-SIM type;   the adaptor has the form of a standard card of the MultiMedia Card type;   the adaptor has the form of a standard card of the Secure Digital type;   the adaptor has the form of a standard card of the Memory Stick type.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other characteristics and advantages of the invention will emerge from a reading of the following detailed description, for an understanding of which reference will be made to the accompanying drawings, in which: 
         FIG. 1  is a perspective view which shows schematically a first embodiment of an adaptor according to the teachings of the invention and a mini-card before it is fitted in the adaptor; 
         FIG. 2  is a view in longitudinal section which depicts schematically the adaptor of  FIG. 1  when the mini-card is occupying its connection position inside the adaptor, the cover of the adaptor being in the closed position; 
         FIG. 3  is a view similar to that in  FIG. 2  which depicts a second embodiment of the adaptor according to the invention; 
         FIGS. 4 to 7  are views similar to that in  FIG. 2  which illustrate several steps of the method of manufacturing the adaptor of  FIG. 3 ; 
         FIG. 8  is a view similar to that in  FIG. 2  which depicts a third embodiment of the adaptor according to the invention; 
         FIG. 9  is a view similar to that in  FIG. 2  which depicts a fourth embodiment of the adaptor according to the invention. 
     
    
    
     DETAILED DESCRIPTION 
     For the description of the invention, the orientations vertical, longitudinal and transverse will be adopted non-limitingly in accordance with the reference frame V, L, T indicated in the figures. 
     In the following description, identical, similar or analogous elements will be designated by the same reference numbers. 
       FIGS. 1 and 2  depict a first embodiment of an adaptor  10  which is produced in accordance with the teachings of the invention. 
       FIG. 1  therefore depicts an adaptor  10  for the electrical connection of an integrated-circuit mini-card  12  in a main connector designed to receive an electronic integrated-circuit memory card with contact, here a card of the MMC type. 
     The main connector, which is not shown here, is a conventional connector able to receive in a complementary manner an electronic memory card of the MMC type, so as to enable an apparatus electrically connected to the connector to process the data stored in the said card. In order to know the detailed characteristics of the electronic memory card of the MMC type, reference can be made to the document “MultiMediaCard System Specification Version 2.11 Official Release @ June 1999 MMCA”, already cited. 
     The standard dimensions of an MMC card are as follows: longitudinal dimension (length) of 32 mm, transverse dimension (width) of 24 mm, and vertical dimension (thickness) of 1.4 mm. The external size of the adaptor  10  must therefore comply with these dimensions. 
     Naturally the present invention is not limited to this memory card format but applies to any memory card format whose dimensions are compatible with the use of a mini-card. 
     In particular, the invention applies to an adaptor  10  in which the mini-card  12  extends partly outside the main body of the adaptor. 
     The mini-card  12  is here of the standard format of the mini-SIM type, which corresponds to the AFNOR standard CEN/TC 224N 405 of 10 May 1993. Such a mini-card  12  is sometimes designated by the term “plug-in” in the field of chip cards. 
     Naturally the present invention is not limited to mini-cards of the mini-SIM type but applies to any type of integrated-circuit data medium with a overall size less than that of the electronic memory card concerned, and having contact strips  14  for electrical connection thereof. 
     The mini-card  12  has a general rectangular shape which comprises a cant  16  having the function of positive location, which will be explained hereinafter. 
     The mini-card  12  comprises two planar main faces  18 ,  20 , one ( 18 ) of which is provided at the contact strips  14 , and comprises, in its thickness, integrated circuits or chips (not shown). 
     The adaptor  10  comprises a main body  22  in the form of an electronic memory card, here in the form of an MMC card. 
     Naturally, according to variant embodiments (not shown) of the invention, the adaptor  10  can take the form of another type of standard electronic memory card, in particular the form of a standard card of the Secure Digital type, or the form of a standard card of the Memory Stick type. 
     The main body  22  has here a general rectangular form which comprises a locating cant  24  corresponding to the cant provided in the MMC card format. 
     The body  22  is produced from an insulating material, for example a plastics material. 
     The top main face  26  of the body  22  is provided with parallel longitudinal conductive areas  28  which are arranged in the vicinity of a transverse edge of the body  22 , or connection edge  30 . 
     The body  22  delimits, in its thickness, a complementary housing  32  of the mini-card  12  which emerges here in the top main face  26  of the body  22  to enable the mini-card  12  to be fitted. 
     The housing  32  comprises a bottom wall, or connecting wall  34 , which is substantially parallel to the top face  26  of the body  22  and which is provided with connecting pads  36 . 
     The connecting pads  36  are arranged in the connecting wall  34  so that it is in contact respectively with the contact strips  14  of the mini-card  12 , when the mini-card  12  occupies its electrical connection position in the housing  32 , or connection position. 
     Each connecting pad  35  is electrically connected to an associated conductive area  28  of the adaptor  10 . 
     According to the first embodiment depicted here, considering in particular  FIG. 2 , the body  22  comprises a series of conductive metallic blades  38  which each comprise a first end section  40  constituting a conductive area  28  and a second end portion  42  constituting an associated connecting pad  36 . 
     The first end section  40  of each blade  38  extends substantially longitudinally on the top face  26  of the body  22  in the vicinity of the connecting edge  30  of the adaptor  10 , and the second end section  42  extends substantially longitudinally below the connecting wall  34  of the housing  32 . 
     Advantageously, the body  22  is moulded around the conductive blades  38 . 
     Each blade  38  comprises, between the first  40  and second  42  end sections, an intermediate section  44  which extends here in a roughly vertical direction, and which is embedded in the plastic body  22 . 
     Advantageously, the connecting wall  34  of the housing  32  comprises, opposite the contact strips  14  of the mini-card  12 , a cavity  46  in which the second end section  42  of each blade extends roughly longitudinally, forming a protrusion  48  projecting inside the housing  32 . 
     The cavity  46  has here the form of a rectangular window which opens out at the top in the connecting wall  34  of the housing  32  and at the bottom in the bottom main face  50  of the body  22 . 
     Such an arrangement of the blades  38  in the cavity  46  makes it possible to exploit their elastic properties in order to ensure electrical contact between each connecting pad  36  and the associated contact strip  14  of the mini-card  12 . This is because, when a mini-card  12  is fitted in the housing  32 , it comes into abutment, through its contact strips  14 , against the protrusions  48  of the blades  38 , which causes the downward flexing of the second end section  42  of each blade  38 , counter to the elastic return force which forces the second end section  42  upwards. 
     Advantageously, the conductive metallic blades  38  are produced from formed and cropped grilles, according to a technology similar to that used in the field of chip cards. 
     In accordance with the teachings of the invention a movable cover  52  is mounted on the body  22  of the adaptor  10 . 
     The cover  52  is able to occupy a closed position on the body  22 , in which it at least partially closes off the housing  32 , so as to hold the mini-card  12  in the connection position, or the position of electrical connection by contact, in the housing  32 , and so as to stiffen the overall structure of the adaptor  10 . 
     The cover  52  is preferably mounted for sliding in a longitudinal direction on the body  22 . 
     Naturally, according to variant embodiments (not shown) of the invention, the cover  52  can be mounted on the body  22  differently, for example by fitting in or “snapping in”, by adhesive bonding, by hooking by means of locking elements manipulated by the user. 
     According to the embodiment depicted here, the cover  52  has overall the form of a profile in an inverted U comprising a transverse main plate  52  and two longitudinal lateral rings  56 ,  58 , which are substantially parallel to the longitudinal vertical faces  60 ,  62  of the body  22 . 
     Each lateral ring  56 ,  58  is provided, at its bottom end, with a return  64 ,  66  which is contained in a substantially transverse longitudinal plane and which comes into abutment against a portion of the bottom main face  50  of the body  22 , so as to guide the cover  52  in longitudinal sliding with respect to the body  22 . 
     According to the embodiment depicted here, the bottom main face  50  of the body  22  comprises two longitudinal shoulders  68 ,  70  substantially complementary to the returns  64 ,  66  on the cover  52 , so as to facilitate the longitudinal guiding and the holding of the cover  52  on the body  22 , and so that the external size of the adaptor  10 , taking account of the cover  52 , corresponds to the external size of an MMC card. 
     The cover  52  stiffens the structure of the adaptor  10  at the same as it holds the mini-card  12  in abutment against the connecting pads  36 , that is to say in the connection position in the housing  32 . 
     The stiffness of the cover  52  in particular compensates for the flexibility of the body  22  and of the mini-card  12 , which are produced from plastics material. 
     The cover  52  is preferably produced from metal, which confers adequate stiffness on it. 
     According to a variant embodiment (not shown) the cover  52  can be produced from a non-metallic material having appropriate stiffness characteristics. 
     Advantageously, the cover  52  is not smooth or planar on the surface but is “profiled” so as to increase its stiffness, which confers on it improved properties of mechanical strength and abutment against the mini-card  12 . 
     For example, the main plate  54  of the cover  52  can comprise embossings (not shown), convex towards the housing  32 , which increases the stiffness of the cover  52  and therefore the stiffness of the vertical abutment of the main plate  54  against the mini-card  12 , so as to keep the mini-card  12  in abutment towards the connecting wall  34  with a view to ensuring good electrical connection by contact between the connecting pads  36  and the contact strips  14 . 
     Advantageously, the main plate  54  forms, with at least one of the lateral wings  56 ,  58 , an angle slightly less than the angle formed by the corresponding edge of the body  22 , which creates a stress line in the cover  52  which reinforces its stiffness. 
     The functioning of the adaptor  10  is as follows. 
     The mini-card  12  is first of all fitted in the housing  32 , in a direction substantially perpendicular to the plane of the body  22 . The mini-card  12  then occupies its connection position in the adaptor  10 , each of its contact strips  14  being electrically connected to a conductive area  28  of the adaptor  10 . 
     At the time of this fitting, the main face  18  of the mini-card  12  comprising the contact strips  14  is arranged opposite the connecting face  34 . 
     In the embodiment depicted here, no other positioning of the mini-card  12  in the housing  32  is possible, because of the presence of the locating cant  16  on the mini-card  12 , by virtue of the shape of the housing  32 , which comprises a locating cant  72  complementary to that of the mini-card  12 . 
     After the mini-card  12  is fitted, the cover  52  is moved in longitudinal sliding on the body  22  as far as a closed position in which the main plate  54  covers the opening in the housing  32 , which holds the mini-card  12  in the housing  32  in vertical abutment against the connecting wall  34 . 
     The assembly formed by the adaptor  10  and mini-card  12  in the connection position can then be inserted in a connector designed for an MMC card, which enables the connector to process the data stored in the mini-card  12 . 
     It will be noted that a mini-card  12  generally comprises at a maximum eight contact strips  14 , so that it can be mounted only in an adaptor  10  of the type which comprises at a maximum eight active conductive areas  28  corresponding to the contact strips on the mini-card  12 . 
     Naturally the electrical connection between the conductive areas  28  and the contact strips  14  is necessary only for the contact strips  14  which are active and which are necessary for the connector to allow the processing of the data stored in the mini-card  12 . 
       FIG. 3  depicts a second embodiment of an adaptor  10  according to the teachings of the invention. 
     The adaptor  10  according to the second embodiment is distinguished from the first through the embodiment of the conductive areas  28  and the connecting pads  36 , as well as through the embodiment of the electrical connection between the areas  28  and the pads  36 . This is because the conductive areas  28  and the connecting pads  36 , as well as the electrical connections between the areas and the pads, are implemented using a known technology for the production of printed circuits. 
     Thus the conductive areas  28  are produced, on the top main face  26  of the body  22 , by deposition and etching of a layer of conductive material, for example based on copper. 
     Each conductive area  28  is arranged in line with a vertical connecting well  74  or conductive via, which extends between the top main face  26  and the bottom main face  50  of the body  22 . 
     The wall of each connecting well  74  is coated with a layer  76  of conductive material, for example the same material as that which is used for producing the conductive areas  28 , so as to electrically connect each conductive area  28  with the bottom main face  50  of the body  22 . 
     Each connecting pad  36  is arranged in line with a vertical connecting well  78  which extends between the connecting wall  34  of the housing  32  and the bottom main face  50  of the body  22 . 
     A film  80  of conductive elastic material or conductive adhesive, for example silicon containing metallic particles, is deposited in each connecting well  78 . The conductive adhesive forms a “heap” in each connecting well  28  and “overflows” on the connecting wall  34  side so as to form a protrusion  28 , protruding inside the housing  32 , which constitutes a connecting pad  36 . 
     The wall of each connecting well  78  associated with a connecting pad  36  is here coated with a layer  84  of conductive material, for example the same material as that which is used for producing the conductive areas  28 . 
     As the conductive adhesive  80  forming each connecting pad  36  is in contact with the layer  84  of conductive material lining the wall of the associated connecting well  78 , each connecting well  78  electrically connects the associated pad  36  with the bottom main face  50  of the body  22 . 
     The bottom main face  50  of the body  22  comprises a series of conductive strips  86  which are connected for example in the same way as the conductive areas  28 , by deposition and etching of a layer of conductive material based on copper. 
     These conductive tracks  86  are arranged on the bottom main face  50  of the body  22  so as to electrically connect the bottom end of each connecting well  74 , associated with a conductive area  28 , to the bottom end of each connecting well  78 , associated with a corresponding connecting pad  36 . 
     The conductive tracks  86  and the connecting wells  74 ,  78  therefore electrically connect each conductive area  28  to the corresponding connecting pad  36 . 
     The elasticity of the conductive adhesive  80  forming each connecting pad  36  guarantees the electrical connection by contact between each connecting pad  36  and the associated contact strip  14  of the mini-card  12 , here despite any lack of co-evenness between the connecting face  34  of the housing  32  and the opposite face  18  of the mini-card  12 . This is because, when the mini-card  12  is placed in the housing  32 , the contact strips  14  come into abutment vertically against the associated connecting pads  36 , causing a slight crushing of these pads  36 , by elastic deformation, which compensates for the defects in co-evenness. 
     The functioning of the adaptor  10  according to the second embodiment is similar to the functioning of the adaptor  10  according to the first embodiment. 
       FIGS. 4 to 7  depict several intermediate steps of an example of a method for manufacturing the adaptor  10  according to the second embodiment. 
     During a first step, which is illustrated by  FIG. 4 , the body  22  is produced from insulating material, for example by plastic moulding. 
     The connecting wells  74 ,  78  can be produced during this first step, for example by drilling. 
     During a second step, which is illustrated by  FIG. 5 , a layer of conductive material, for example copper, is deposited on the top  26  and bottom  50  faces of the body  22 , as well as on the walls of the connecting wells,  74 ,  78 . 
     This layer of conductive material is etched so as to form the conductive areas  28  on the top face  26  of the body  22  and a series of conductive tracks  86  on the bottom face  50  of the body  22 . 
     During a third step, which is illustrated by  FIG. 6 , the housing  32  is machined in the top face  26  of the body  22 . 
     During a third step, which is illustrated by  FIG. 7 , the connecting pads  36  are formed by the deposition of a “heap” of conductive adhesive  80  in the connecting well  78  associated with the connecting wall  34 . 
     The adaptor  10 , which is depicted in  FIG. 3 , is then obtained. 
     According to a third embodiment of the invention, which is depicted in  FIG. 8  and which is similar to the second embodiment, the conductive tracks  86  are arranged on the top main face  26  of the body  22 , and the housing  32  emerges in the bottom main face  50  of the body  22 . 
     In this embodiment, only the connecting pads  36  comprise associated connecting wells  78 . 
     The top opening of each connecting well  78  is here blocked by the end portion  88  of a conductive strip  86 , so as to facilitate the filling of the connecting well  78  with the conductive adhesive  80  forming a connecting pad  36  in the housing  32 . 
     The internal walls of the connecting well  78  are not coated with conductive material, so that each connecting pad  36  is electrically connected with the associated conductive track  86  by contact between the conductive adhesive  80  and the end portion  88  of the track  86  which blocks the top opening of the well  78 . 
     According to a fourth embodiment of the invention, which is depicted in  FIG. 8  and which is similar to the second embodiment, the connecting pads  36  are metallic domes  90  arranged in complementary cavities  92  produced in the connecting face  34  of the housing  32 . 
     The conductive tracks  86 , which electrically connect the metallic domes  90  with the corresponding conductive areas  28 , are here arranged on several layers, here two layers. 
     The body  22  of the adaptor  10  is therefore produced in the form of two layers of plastic  94 ,  96  superimposed vertically, in accordance with the technology used for producing chip cards with a support of the “laminated” type. 
     A first part of the connecting pads  36  is connected to the corresponding conductive areas  28  by a first series Si of conductive tracks  86  which are arranged between the two layers of plastic  94 ,  96 , in accordance with the example depicted in  FIG. 9 . 
     It will be noted that, for this first series Si of conductive tracks  86 , the connecting wells  74  associated with the conductive areas  28  do not need to pass through the bottom layer  96  of the body  22 . 
     The conductive tracks  86  of this first series Si extend here into the bottom of each cavity  92  associated with a metallic dome  90 . 
     A second part of the connecting pads  36  is connected to the corresponding conductive areas  28  by a second series S 2  of conductive tracks  86  which are arranged on the bottom main face  50  of the body  22 , in accordance with the second embodiment depicted in  FIG. 3 . This second series S 2  of conductive tracks  86  is not depicted in  FIG. 9 . 
     For this second series S 2  of conductive tracks  86 , the connecting wells  74  associated with the conductive area  28  must pass through the two layers  94 ,  96  of the body  22 , and each metallic dome  90  comprises a connecting well  78  which extends vertically between the associated cavity  92  and the bottom main face  50  of the body  22 .