FR2889756A1 - Safety arrangement for protecting electrical connector, has conducting element connected to detection circuit such that attempt of drilling element using drilling part, to attain contact strips, causes state change in detection circuit - Google Patents

Abstract

The arrangement has an electrical conducting element (34) connected to a detection circuit such that an attempt of drilling the conducting element using a drilling part such as a metal drill, for attaining electrical contact strips (32, 32a), causes a state change in the detection circuit. The conducting element has conductor paths (36) arranged to constitute a protection network (40) and extends with respect to a zone (Z) of the contact strips to be protected, without electrical contact with the contact strips.

Description

"Security arrangement against fraud for

  FIELD OF THE INVENTION The present invention relates to a security arrangement against fraud for an electrical connector for a smart card.

  The invention more particularly relates to a security arrangement for an electrical connector for connecting an electrical memory card with contacts, called smart card, comprising in one of its large horizontal faces, a plurality of ranges of electrical contacts, the connector comprising a generally rectangular block of insulating material which has an upper face, for example flat and horizontal, and a plurality of elastically deformable contact blades disposed parallel to a longitudinal direction is horizontal.

STATE OF THE ART

  Among the different contact blades arranged parallel to one another, in one or more groups of several blades - for example in two groups of four blades aligned longitudinally in pairs - the connector comprises at least a first contact blade called signal.

  Among the so-called signal contact blades, there is for example the so-called input / output contact blade or I / O blade, which is for example in contact with a corresponding range of the smart card and which can produce an I / O signal when the smart card is in position.

  Among the different contact blades, the connector also comprises at least one second so-called ground contact blade which is intended to be in contact with a corresponding range of the card and which is connected to a ground circuit of the read / write device. equipped with the connector.

  The various fraud attempts on read / write devices equipped with such a connector includes a step to reach said contact blade I / O.

  Such a maneuver is decisive to allow fraud of the smart card.

  For this purpose, a fraudster may for example drill a hole in the insulating block carrying the contact blades and / or in the printed circuit board which, on its upper face, is equipped with the connector.

  It is known to use arrangements for improving the general security of read / write devices by providing means for detecting and preventing fraud attempts.

  French Patent Application No. 04.51974 filed on 07.09.2004, discloses an electrical connector comprising a metal plate forming a protective cage which extends opposite a portion vis-à-vis the contact blade I / O, and which is electrically connected to a ground plate of the connector.

  Thus, any attempt to reach the contact blade I / O by means of a metal object, and for example by means of a metal drill, results in establishing an electrical connection between the protective plate which is connected to the mass and the first contact blade.

  There is then a short circuit, by grounding the first contact blade, which constitutes a signal representative of an attempted fraud.

  However, such an arrangement does not effectively protect attempts of fraud by intrusion by the upper and / or side faces of the connector thus protected. It also has the disadvantage of not being concealed and it is thus possibly easier for a fraudster to circumvent such an arrangement.

  Fraud detection occurs only "through" the connector blades, which can cause deterioration of the signal processing circuitry to which the connector is connected.

  In addition, the connection of the plate to the mass plate results in complex structures and arrangements.

  The aim of the invention is to provide a particularly more discreet arrangement, protecting a larger area of the contact blades, in particular an area vertically above the contact blades and making it possible to detect a fraud before there is a contact between the piercing member and the target contact blade.

  SUMMARY OF THE INVENTION For this purpose, the invention proposes an electrical connector of the type mentioned above, characterized in that the arrangement comprises at least one electrically conductive element, for example substantially plane, which extends through example horizontally, facing an area of contact blades to protect, without electrical contact with the latter, and which is adapted to be connected to a detection circuit so that an attempt to intrude through the conductive element , for example by means of a member, in particular in order to reach a contact blade, causes a change of state in the detection circuit.

  According to other features of the invention: the conductive element comprises at least one conductive track is arranged in a serpentine to constitute a protection network; the protection network comprises several distinct conducting tracks; the conductive element comprises two conductive layers insulated from one another by an insulating element; one of the two conductive layers comprises at least one conductive track arranged in a coil to form a protection network; the arrangement comprises a protective cover comprising an upper plate and lateral faces and which surrounds the insulating block and the contact blades; - The protective cover is a cover for guiding the smart card and whose inner face of the plate is facing said area of the contact blades; the conductive element is carried by the upper plate and / or at least one side of the lid; the conductive element is in the form of a film attached to at least the top plate and / or at least one side of the lid; the conductive element is deposited on the upper plate and / or at least one side of the lid by a deposition technique using an ink or a conductive paint; is - the conductive element constitutes an insert which is embedded in the lid during the manufacture by molding of the latter.

BRIEF DESCRIPTION OF THE FIGURES

  Other features and advantages of the invention will become apparent on reading the following detailed description for the understanding of which reference will be made to the appended drawings in which: FIG. 1 is a rear three-quarter perspective view and of an exemplary embodiment of an electrical connector for a smart card which is produced according to a first embodiment of the invention; FIG. 2 is an exploded perspective view of three-quarter rear and bottom view according to FIG. 1; FIG. 3 is a view from above on a very large scale of the protective conductive element of FIG. 2; FIG. 4 is a simplified partial diagram of a detail of the connector of FIG. 1; - Figure 5 is a diagram of an electrical connector according to a second embodiment of the invention; FIG. 6 is a plan view in its expanded form of the protective conductive element of FIG. 5; - Figure 7 is a sectional diagram along the plane 7-7 of the conductive element of Figure 6 on a larger scale; - Figure 8 is an exploded schematic view of a protective cover and a connector.

DETAILED DESCRIPTION OF THE FIGURES

  In the following description, identical, similar, or like components will be designated by the same reference numerals.

  Without limitation, to facilitate understanding of the description and claims, we will adopt the terms vertical, is horizontal, lower, upper, upper, lower, transverse, longitudinal, etc. with reference to the trihedron L, V, T indicated in the figures.

  There is shown in Figure 1 a connector 10 which is constituted essentially by a body or housing 12 which is made for example of insulating plastic material made by molding.

  The general design of the connector 10 with its insulating body 12 is here of the type described and shown in US-A-5,775,949.

  The body 12 is constituted essentially by an upper cover 14 here generally horizontal and by a lower horizontal plate 16 which once nested, delimit between them a slot 18 of longitudinal introduction, back forward in the direction indicated by arrow "z" in Figure 1, a smart card (not shown). The smart card here comprises in its underside oriented facing an upper face 20 of the horizontal plate 16, conductive areas arranged in a standardized manner.

  As can be seen in particular in Figure 2, the cover 14 consists of a horizontal plate 22, two vertical side plates 24 and 26 which extend in the longitudinal direction "L" and a vertical bottom plate 28 which extends in the transverse direction "T". The two side plates 24 and 26 are opposite and allow lateral guidance of the chip card in the longitudinal direction "L" by limiting its transverse displacement. The bottom plate 28 is perpendicular to the side plates 24 and 26 and delimits the bottom of the slot 18.

  The plates or walls 22, 24, 26 and 28 of the cover 14 have inner faces facing the slot 18 respectively 221, 241, 261 and 281, and comprise outer faces respectively 22E, 24E, 26E and 28E.

  As can be seen in FIG. 2, in its central part, in the transverse direction "T", the plate 16 constitutes an insulating contact block 30 which carries, in known manner, here two groups of four contact blades. electric 32.

  The lower plate 16 also makes it possible to assemble and fix the connector 10 in a read / write device (not shown), in this case using four hooks 33.

  The general design of the contact block 30 with its blades 32 is for example described and shown in detail in US-A-6.447. 338.

  The aim of the invention is to protect all the contact strips 32 against an attempted intruder fraud, for example by establishing an electrical contact with the contact blades 32 by means of a metal object, piercing the connector 10.

  For this purpose, the horizontal plate 22 of the cover 14 has, here on its inner face 221, facing the insulating block 30 of contact blades 32, an electrically conductive element 34 fixed for example by an adhesive tape or an adhesive film or glue.

  The conductive element 34 of protection is in the form of a planar element as illustrated in FIG. 3. It is a film 38 or a sheet of insulating material which serves as a support for a series of conductive tracks 36.

  In this exemplary embodiment, the film 38 carries on one of its large faces an array of four thin continuous conductive tracks 36.

  As can be seen in FIG. 3, the four tracks 36 snake without crossing over a zone Z to be protected, above the contact blades 32, to constitute a network 40 of finely clamped tracks 36.

  The free ends of the four tracks 36 grouped into bundles form an exit layer 42 and an inlet layer 44 which here extend in a transverse direction.

  Each of the plies 42 and 44 may be connected to a detection circuit (not shown), for example each passing through a slot 45 located at the connection of the plate 24 and the plate 22.

  When a fraudster tries to pierce the cover 14 using for example a metal drill, in a first hypothesis, he cuts off at least one of the tracks 36, as illustrated by the point P1 in FIG. case, the current no longer circulates in the interrupted track 36 and the detection circuit detects the discontinuity of the sectioned track 36 and emits a signal representative of an attempted fraud. This detection mode has the advantage of being effective even if the body used to drill is not a conductive material.

  In a second hypothesis, the drill damages one or more track (s) 36 and reduces its section at the point of drilling, as illustrated by point P2 in FIG. 3. It is known that the resistance of a wire, or track 36 here, is inversely proportional to the area of its section. In this case, the resistance of the damaged track 36 is lower than its initial resistance, which allows the detection circuit to detect a fraud by measuring the variation of the resistance of the damaged track (s) 36. (s).

  In a third hypothesis, the fraudster drills a hole with a metal drill between two separate tracks 36, as illustrated in point P3 in FIG. 3. The two drilled tracks 36 come into electrical contact via the metal drill, io this allows the detection circuit to detect a short circuit between the two tracks 36 and to emit a signal representative of an attempted fraud.

  In these three detection cases, all communication between the smart card and the read / write device is then prevented to avoid possible fraud or possible piracy.

  In this embodiment, the conductive element 34 protects only one zone Z of the contact blades 32, in particular a zone Z situated vertically of the contact blades 32.

  To increase this protection zone, it is of course conceivable to use a detection circuit covering a larger area, extending for example to the side plates 24 and 26 and the bottom plate 28 of the cover 14.

  According to another embodiment, illustrated in Figures 5, 6 and 7, the conductive element 34 is a flexible sheet 38 which comprises an upper layer 46 and a lower layer 48, which are here two conductive layers, for example copper, and which are insulated from each other by an intermediate layer 38 of insulating material.

  The conductive element 34 has fold zones shown in dashed lines in FIG. 6, enabling it to match the shapes of the cover 14, for example forming right angles between the different faces of the cover 14 on which the conductive element 34 is installed.

  Side portions 54 of the conductive element 34 are folded on the side plates 24 and 26 of the connector 10 so as to extend facing the faces 24E and 26E respectively.

  A portion 56 at the front of the conductive element 34 is folded over the bottom plate 28 facing the face 28E of the cover 14.

  In this embodiment, the conductive element 34 has on its periphery two front fixing lugs 52 and two rear fixing lugs 53, each having a fixing hole 57. The four lugs 52 and 53 extend transversely. starting from the lateral portions 54 of the conductive element 34.

  The fixing lugs 53, located at the rear of the conductive element 34, are bent approximately at right angles, so as to extend below the horizontal plate 16 of the connector 10 and so that the two holes 57 are each crossed by a hook 33 to secure the conductive element 34.

  The fixing lugs 52, located at the front of the conductive element 34, are folded a first time approximately at right angles, and clamped between the cover 14 and the horizontal plate 16 so as to extend below the latter. The fastening tabs 52 are then folded a second time approximately at right angles, and are inserted into a slot 58 cut in a longitudinal direction in the plate 16 and extend after a last folding at right angles under the outer face of the plate. 16 so that the two holes 57 are each traversed by a hook 33 to secure the conductive element 34.

  This fastening principle is nonlimiting, it is for example possible to glue the conductive element 34 on the lid 14. i0

  The connector 10 is mounted on the read / write device on a printed circuit board (not shown), which is equipped with four connection pads with which the fastening tabs 52 are in contact. Thus, the upper layer 46 of the front mounting tabs 52 and the lower layer 48 of the rear mounting tabs 53 are electrically connected to the detection circuit via the printed circuit board.

  The two layers 46 and 48 thus connected are not at the same potential. According to this embodiment, the layer 46 is for example connected to ground, and the layer 48 is at a higher potential, for example two volts.

  Thus, the method of fixing the two rear legs 53 makes it possible to limit the risk of fraud by moving the cover 14 and the horizontal plate 16 apart to directly access the contact blades 32, because here, the cover 14 and the plate 16 are connected by the conductive element 34.

  When a fraudster attempts to drill the cover 14 vertically using a metal drill 60 according to FIG. 7, he puts the two layers 46 and 48 of the conductive element 34 into contact with each other. The two layers 46 and 48 being at the same potential, the drill causes a short circuit that the detection circuit connected to the two layers 46 and 48 can detect and then produces a signal representative of the attempted fraud.

  Thus, any communication between the smart card and the reading / writing device is prevented to avoid possible fraud or possible piracy.

  As can be seen in FIG. 8, it is possible to arrange the conductive element 34 on an independent part of the electrical connector 10, both for a conductive element according to the first embodiment and for a conductor according to the second embodiment. of realization. ii

  Said independent part is for example a protective cover 62 overlapping or surrounding the connector 10. Said protective cover 62 comprises a plate, here planar and substantially horizontal, which extends opposite the cover 14 of the connector 10, as well as three side faces 66, 68, 70 facing the sides 24, 26, 28 of the cover 14 respectively.

  The protective cover 62 can be arranged on a read / write device, for example already having a connector 10.

  The invention is not limited to the previously described embodiments.

  By way of non-represented variants, the invention is applicable to all types of connectors comprising an insulating contact-carrying block 30, independently of the design of the means for guiding the card, which can be put in place. in any orientation relative to the insulating block contact carrier 30.

  The conductive element 34 may be incorporated in the cover or the protective cover 62 during its manufacture by molding in the form of an embedded insert, to increase the discretion of the security arrangement.

  Similarly, it is possible to combine the embodiments described above, by applying on the outer faces of the cover 14 or the protective cover 62, a conductive element 34 comprising a circuit forming a network described according to the first embodiment and in applying on the inner faces 221, 241, 261 and 281 of the cover 14 or the protective cover 62 a conductive element 34 comprising several layers such as that described according to the second embodiment, or vice versa.

  Similarly, it is possible to qualify the second embodiment of the security arrangement by replacing one of the conductive layers 46 or 48 by a conductive track 36 such as that described according to the first embodiment.

  It is also possible to multiply the conductive elements 34 of the same type to increase safety, for example by arranging a conductive element 34 described according to the first embodiment on each face of the cover 14 or the protective cover 62.

  Similarly, the conductive element 34 may be formed by deposition techniques such as pad printing or screen printing using an ink or conductive paint.

  For example, the conductive element 34 comprising several tracks 36 described above according to the first embodiment is deposited on the cover 14 or the protective cover 62, advantageously on its inner face 221 to increase discretion. Similarly, the conductive element 34 according to the second embodiment comprising two conductive layers, can also be deposited on the cover 14 or the protective cover 62, the latter acting as an insulator between the two conductive layers 46 and 48.

  Advantageously, the plies 42 and 44 of the conductor 34 according to the first embodiment, can be arranged transversely each on one side of the connector 10. Such an arrangement further limits the risk of fraud by attempting to separate the cover 14 and the horizontal plate 16 to directly access the contact blades 32 because the layers 42 and 44 bind the cover 14 and the plate 16 between them, so their spacing requires the rupture of at least one layer 42 and / or 44, which would cause a signal representative of a fraud.

  The connection of the conductive elements 34 to a detection circuit can also be effected by means of some of the connecting tabs of the contact blades 32.

Claims (12)

  1. Safety arrangement for an electrical connector (10) for connecting an electrical memory card with contacts, called "smart card", comprising in one of its large horizontal faces, a plurality of electrical contact pads, the connector (10) comprising a generally rectangular block (30) of insulating material which comprises an upper face (20) and a plurality of elastically deformable contact blades (32, 32a) arranged parallel to a longitudinal horizontal direction, characterized in that the arrangement comprises at least one conductive element (34) of electricity which extends opposite a zone (Z) of the contact blades (32, 32a) to be protected, without electrical contact with the latter.   1s 2. Safety arrangement according to claim 1, characterized in that the conductive element is connected to a detection circuit so that an attempt to intrude, in particular piercing, through said conductive element (34) by means of an organ, in particular with a view to reaching a contact blade (32, 32a), causes a change of state in the detection circuit.   3. Security arrangement according to one of claims 1 or 2, characterized in that the conductive element (34) comprises at least one conductive track (36) is arranged in a serpentine to form a network (40) of protection.   4. Safety arrangement according to the preceding claim, characterized in that the network (40) of protection comprises a plurality of separate conductive tracks (36).   5. Safety arrangement according to one of claims 1 or 2, characterized in that the conductive element (34) comprises two conductive layers (48, 46) insulated from each other by an insulating member (38).   6. Safety arrangement according to the preceding claim, characterized in that one of the two conductive layers (48, 46) comprises at least one conductive track (36) arranged in a serpentine to form a network (40) protection.   7. Safety arrangement according to the preceding claims, characterized in that it comprises a protective cover (62) comprising an upper plate (64) and side faces (66, 68, 70) and which surrounds the insulating block (30). ) and the contact blades (32, 32a).   8. Safety arrangement according to the preceding claims, characterized in that the protective cover (62) is a cover (14) for guiding the chip card and whose inner face (221) of the plate (22) is facing said zone 1s (Z) contact blades (32, 32a).   Security arrangement according to one of the preceding claims, characterized in that the conductive element (34) is carried by the upper plate (22) and / or at least one side (24, 26, 28) of the cover. (14).   Safety arrangement according to claims 1 to 8, characterized in that the conductive element (34) is in the form of a film attached to at least the upper plate (22) and / or at least one side ( 24, 26, 28) of the cover (14).   11. Safety arrangement according to claims 1 to 8, characterized in that the conductive element (34) is deposited on the upper plate (22) and / or at least one side (24, 26, 28) of the cover (14). ) by a deposition technique using an ink or a conductive paint.   12. Safety arrangement according to claims 1 to 8, characterized in that the conductive element (34) is an insert which is embedded in the cover (14) during the manufacture by molding thereof.