Abstract:
The invention relates to a seal device, including a locking pin and a sleeve, the locking pin having a head and a stem having a groove which interacts with a locking ring disposed in the sleeve to lock the sleeve onto the pin by insertion. The sleeve also includes a first transponder housed in the upper portion of the sleeve at a depth that is greater than the height of the stem and the locking pin also comprises a second transponder disposed on the outer periphery of the stem. Each transponder includes storage means for storing at least one unique identification code. Thus, any unauthorized handling of the seal device may be detected even if the latter is completely replaced after breakage.

Description:
TECHNICAL FIELD OF THE INVENTION 
   The present invention relates to a seal device for closing and marking objects. More particularly, the invention relates to the seal devices that use electronic identification means. 
   BRIEF DESCRIPTION OF RELATED ART 
   Many types of seals are currently used for inspecting the routing or storage of products or materials that have more or less important security or inspection requirements, such as, for example, freight merchandise of any kind, nuclear materials, certain types of waste or money. 
   The technologies employed to produce the seals are extremely varied and depend mainly on the usage and degrees of security required. 
   Thus, when the requirement is simply to check on the integrity of an object, such as a bag or a container, the function of the seal is to guarantee that the object has not been opened without authorization. In this case, low cost devices, such as simple plastic or metal collars affixed to the opening members of the object may be used. A visual inspection of the integrity of the collar structure then suffices to check whether or not the seal has been violated. 
   On the other hand, there is an increasing number of fields, such as international transport, in which the seals are required not only to fulfill their basic function, which is to be able to certify the inviolability of the object, but also to be able to supply information during and after their transportation. Thus, devices currently exist that comprise mechanical means of sealing with which are associated electronic or optical means that can be used to store and transmit information. 
   However, the current seal devices that comprise electronic means are complex and costly. They are usually designed for a specific use and cannot be used with just any type of object. In addition, they have a fragile mechanical structure which makes them very sensitive to handling and transportation operations which further restricts their use. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention aims to remedy the aforementioned disadvantages and to produce a low cost multiple use seal device that is mechanically robust and that contains information that can be read simply and quickly. The device must also allow a secure and easy inspection of the integrity of the seal. 
   These objects are achieved thanks to a seal device, comprising a locking pin and a sleeve, the locking pin comprising a head and a stem comprising a groove which interacts with a locking ring disposed in the sleeve to lock said sleeve onto the pin by insertion, characterized in that the sleeve also comprises a first transponder housed in the upper portion of the sleeve at a depth that is greater than the height of the stem and in that the locking pin also comprises a second transponder disposed on the outer periphery of the stem, each transponder comprising a substrate on which are formed an electronic circuit and an antenna, said electronic circuit comprising storage means for storing at least one unique identification code. 
   Thus, thanks to the seal device according to the invention, it is possible to mark any object with a unique identity, so that the object can be inspected and monitored during and after its transportation. In addition, the integrity inspection of the seal device is carried out by interrogation of a second transponder, which requires no dismantling of the seal and can be used in any location to inspect the conformity of the identity information contained in the transponder. 
   According to a particular aspect of the invention, the sleeve also comprises a third transponder held inside the latter at a depth that is less than the height of the stem, the transponder comprising a substrate on which are formed an electronic circuit and an antenna, said electronic circuit comprising storage means for storing at least one unique identification code. 
   Thanks to this third transponder placed at intermediate depth in the sleeve, it is possible to verify that the device has been correctly installed, that is to say that the sleeve has been correctly locked onto the pin making it impossible to open the object without destroying the seal device. 
   To ensure a complete destruction of the third transponder when the seal device is installed, it is held in the sleeve by an annular element which covers at least a portion of the antenna of said transponder. Thus, during an interrogation, the absence of a response from the third transponder indicates a correct installation. 
   The first transponder may contain, in addition to a unique identification code, data relating to the date and location at which the seal device was installed, or information on inspections made on the object during its transportation. The storage means of the first transponder may comprise data encryption means. 
   A further object of the invention is a system of inspecting and monitoring an object, said object comprising at least one seal device as described above, characterized in that it comprises a signal transmission device to read or write information in the transponders of the seal device, processing means and data storage means for entering the information stored in the transponders. 
   Thus, thanks to the system of the invention, the installation and integrity of the seal device may be inspected by remote interrogation of the transponders with no handling of the device. In addition, the information stored in the first transponder, with the exception of the identification code, may be consulted and updated in real time. The data storage means of the system can also be used to store important information, such as the identification code, to allow a subsequent comparison with the codes read on the device in order to detect any unauthorized handling of the device. 
   According to a particular feature, the data storage means can be accessed remotely via a network link. This makes it possible to carry out inspections in any location and at any time by having a reference remotely accessible on the original data associated with the seal device. For example, it is possible to read a code of a transponder during a stage in the transportation of the object marked with the seal device and compare the code read with that originally entered to detect an unauthorized replacement of the seal device. 
   For this purpose, the processing means may comprise software means for confirming the installation of the seal device by interrogation of the third transponder and/or for detecting an unauthorized handling of the seal device by interrogation of the second transponder. The processing means may also comprise a software means for detecting an unauthorized replacement of the seal device by reading the seal device transponder codes and by comparing said codes with the original codes previously entered in the data storage means. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the invention will emerge from the following description of particular embodiments of the invention, given as nonlimiting examples, with reference to the appended drawings, in which: 
       FIG. 1  is a view in perspective of a seal device according to one embodiment of the invention, 
       FIG. 2  is a schematic view of a seal device in locked position and of an interrogation and processing system according to the invention, 
       FIG. 3  is a schematic view of the type of transponder used in the seal device of the invention, 
       FIG. 4  is a schematic view in section showing the seal device during the opening of an object marked with the device, 
       FIGS. 5A and 5B  show the installation steps of the seal device according to the invention, 
       FIG. 6  is a view in perspective of an exemplary application of the invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  shows the seal device  1  according to the invention. The device  1  is formed of a locking pin  10 , and a sleeve  20  intended to be locked onto the pin  10 . The pin  10  and the sleeve  20  form a single-use self-locking mechanical system that is used to mark the closure of any object. For this purpose, the pin  10  comprises a head  11  and a stem  12 , the stem  12  comprising a locking groove  13  which interacts with a locking ring  24  held inside the sleeve  20  by means of a recess  25  that is made in the body  21  of the sleeve. Thus, as illustrated in  FIG. 2 , when the stem  12  of the pin  10  is inserted into the sleeve  20 , the latter is locked onto the stem by means of the portion of the ring  24  extending beyond the recess  25  which then engages in the groove  13  to hold the sleeve on the stem. 
   For example, as illustrated in  FIG. 2 , the device  1  may be used for marking the closure of an object by installing the closure system for the object on two elements  5  and  6  in which a hole  4  has been made. The pin  10  is inserted into the hole  4  and held by the head  11  which has dimensions greater than those of the hole  4 . Then, the sleeve  20  is placed on the stem  12  of the pin, which is used to lock the elements  5  and  6  together. In order to make the device easier to install, the body  21  of the sleeve  20  may comprise a portion  22  adjusted to the dimensions of the hole  4 . Consequently, once the seal device  1  has been installed, the object will not be able to be opened without cutting or breaking the device  1  ( FIG. 4 ). 
   The seal device according to the invention comprises several electronic components of the transponder type. A first transponder  30  is used as a permanent means of storing information relating to the seal device and to the object with which it is associated. The nature of this information and its use will be described in detail hereinafter. Since the transponder  30  is a permanent transponder, it is disposed in a portion of the device in which it will be protected from any damage. For example, as illustrated in  FIG. 1 , the transponder  30  is housed in the top portion of the sleeve  20  at a depth P that is greater than the height H of the stem  12  which corresponds to the maximum penetration distance of the stem into the sleeve. The transponder  30  is held against a cap  23  which closes off the top portion of the body  21  of the sleeve  20 . The transponder  30  may be bonded onto the cap  23 . 
   A second transponder  40  is disposed on the periphery of the stem  12  of the pin  10 . The transponder  40  may be bonded onto the stem  12  to hold it in place on the latter. 
   Finally, a third transponder  50  is held inside the sleeve  20  at an intermediate depth P′, less than the height H of the stem, by a clamp ring  26  placed between the transponder  50  and the transponder  30 . 
     FIG. 3  illustrates the general structure of the transponders  30 ,  40  and  50  that are used in the present invention. As shown in  FIG. 3 , a transponder  100  is formed of a substrate  101  onto which are placed an electronic chip  102  and an antenna  103 . The antenna  103  is formed by a winding which extends all around the periphery of the substrate. One end of this winding is connected to the chip  102 . The chip  102  mainly comprises an electronic circuit for storing data which can be accessed in read and write mode as necessary. Each transponder contains at source a unique permanent code which constitutes the identity of the transponder and which cannot be modified. 
   The data in the memory circuit is read, and where necessary written, by radio frequency transmission thanks in particular to the antenna  103 . If the winding that constitutes the antenna  103  is broken, the latter becomes inoperative and transmission between the chip  102  and the outside can no longer be achieved, thus providing evidence that the component  100  has been damaged. 
   The transponder model described is of the passive type, that is to say that the antenna is used not only for data transmission but also for receiving an activation field for supplying the electronic circuit of the chip with electrical power. It is also possible to use transponders that comprise their own means of supply, such as a battery, the latter being connected to the chip  102  to supply it with power. 
   The type of transponder described above is particularly suitable for the present invention. Specifically, such components have a very small space requirement which makes it possible to house them easily in seal devices such as that of the invention. In addition, the substrate of the component being made of a fragile material such as silicon, it may be easily broken and thus allow the component or at least the antenna of the latter to be broken with little resistance. However, depending on its function in the device of the invention, the shape, the dimensions and the material of the substrate may be adapted as described hereinafter. For example, for the substrate of the transponder  40  that is intended to be placed on the periphery of the stem  12 , preference is given to choosing a flexible material which makes it easier to install the transponder on the stem. In addition, the transponder shown in  FIG. 3  has a square shape. However, with respect to the transponders  30  and  50  in particular, the latter may also have a circular shape to make them easier to integrate into the sleeve. 
   A more detailed description will now be given of the various functions of the transponders that are used in the seal device of the invention. 
   The permanent transponder  30  is used for storing all the pertinent information that will make it possible to identify the object whose closure has been marked with the seal device of the invention. As an example, the object in question may be a container intended to transport an item of merchandise. In this case, the information stored in the transponder  30  may correspond to the date and location of loading and closure of the container, to the nature of the merchandise transported, to the various customs inspections carried out, to the names or the identification of the parties responsible for these inspections, etc. 
   The transponder  40  that is placed on the stem  12  of the pin  10  is used as evidence of the integrity of the seal device. Specifically, as illustrated in  FIG. 4 , any attempt to open the sealed object causes the breakage of the seal device  1  and of the transponder  40  which can consequently no longer be interrogated. To attempt to hide an unauthorized opening, two solutions may be envisaged. The first consists in repairing the cut stem and repositioning it in the seal device. The second solution consists in entirely replacing the seal device with a new one. In both cases, the unauthorized handling can be detected. Specifically, in the first case, in addition to the traces on the sleeve that may provide evidence of such handling, the fraudulent handling will be detected at the time of the next interrogation which will reveal that the transponder  40  does not respond and that, consequently, the seal device has been violated. In the second case, in which the device has been entirely replaced, the read operation will reveal that the transponder identification code has changed and that it does not correspond to that entered on departure. 
   An explanation will now be given of the role of the third transponder  50  of the seal device of the invention. The transponder  50  is used as evidence of the correct installation of the seal device. Specifically, as illustrated in  FIG. 1 , the transponder  50  is kept inside the sleeve  20  at a depth P′ that is less than the height H of the stem  12  of the pin  10  corresponding to the penetration distance of the stem in the sleeve. Consequently, as illustrated in  FIG. 5A , when the sleeve  20  is placed on the pin  10 , the end  14  of the stem  12  will come to butt against the transponder  50 . Consequently, to bring the sleeve to its final position, that is to say to the position in which the ring  24  is locked in the groove  13  of the stem, it will be necessary to break the transponder  50 . More precisely, with reference to  FIGS. 2 and 5B , when the seal device has been correctly installed, the transponder  50  is in two pieces  50 A and  50 B. The piece  50 A corresponds to the portion of the transponder that has been detached by the stem  12  while the piece  50 B corresponds to the portion that is held between the body of the sleeve  21  and the clamp ring  26 . It is necessary to ensure that the clamp ring  26  which holds the piece  50 A of the transponder  50  covers at least a sufficient portion of the transponder to ensure that the transponder is destroyed. As shown in  FIG. 3 , the clamp ring  26  covers at least a portion of the antenna  103  to ensure that the latter breaks when the device is installed. 
   Therefore, so long as the transponder  50  responds to a remote interrogation, it means that it is intact and that the sleeve is not correctly positioned on the pin. 
   Data may be read from and/or entered in the transponders for example with the aid of a radio frequency transmission device  60  shown in  FIG. 2 . The transmission between the device  60  and the transponders is carried out by radio frequency signals RFin and RFout which correspond respectively to the signals received and the signals sent by the device  60 . Thus, with the device  60 , it is possible to read and/or write in the memory of the transponders. 
   As an example, the device  60  may be a portable reader that can be used to read and write data in a transponder. Such a reader comprises a display screen  61 , a keypad  62  and/or means of storing the interrogated data. The reader drives the transponder by radio frequency (RF), for example at a frequency of 13.56 MHz. This wave charges a capacitor present in the circuit of the transponder. When the latter discharges, it sends the reader a code or an item of information written in the memory of the transponder. This type of portable reader can be used to interchange data with the transponders over a distance of approximately 30 cm. Alternatively, it is possible to use various types of non-portable readers which have antenna geometries allowing a serial read/write operation at a greater distance. 
   The code and/or the information of each interrogated transponder is thus sent to the device  60 . In the case of a portable reader, these data may be displayed on its screen  61  and/or stored in its memory. The device  60  may also comprise integrated processing means specially programmed to carry out the inspections described here. 
   Alternatively, the processing means, such as a computer  70 , may be used to process the data from the transponders. In this case, as illustrated in  FIG. 2 , the computer is connected to the device  60 , via a serial link  67 , so that it can interchange data with each transponder memory. In any case, the processing means comprise and run software that can be used to perform all kinds of inspection and monitoring functions based on the data of the transponders. 
   For example, depending on the case, the device  60  or the computer  70  may comprise software means for inspection, at the start, the installation of the device by interrogating the transponder  50 . The information concerning breakage of the transponder  50 , which is therefore evidence that the seal device has been correctly installed, may be used as starting information by the processing means in order, for example, to store the identification codes of one or more transponders for the purposes of future inspections. The software may also be used to establish the correlation between the identification number of one of the transponders and various data such as the location and/or the name of the inspector who installed the seal device, and/or the date on which the latter was installed. The software may also be used to write or update data in the transponders (except for the identification code which cannot be modified). 
   Information, such as the identification codes, may be stored in a database  80  ( FIG. 2 ) which may be accessed on line, via a network link  78  such as an Internet link for example. The transmission device  60 , the computer  70  and the database  80  constitute a system that can be used to inspect and monitor in real time any object that is marked by one or more seal devices of the invention. This can be used to monitor and inspect the merchandise throughout its journey. The integrity of the device may be checked at any time. Specifically, the interrogation of the transponder  40  can be used to determine initially whether the latter is intact and, where appropriate, to compare the code read in the latter with the code originally entered in the database  80  which may be accessed remotely via the network link  78 . 
   Finally, the permanent transponder  30 , which may contain all sorts of information that is added to during the stages of the object&#39;s transportation, thus builds up the history of the seal device which may be consulted in real time by interrogating the transponder  30  at an inspection location. 
   According to the principle of the seal, the latter may be affixed only once without harming its integrity. The seal device according to the invention satisfies the same requirements. It may have many applications. As shown in  FIG. 6 , a plurality of devices  1  are used to mark the closure of a cover  2  on an enclosure  3 . In this case, the elements  5  and  6  correspond to collars in which through-holes of the devices  1  have been made. The integrity of the system thus formed is guaranteed and may be easily inspected as described hereinabove. 
   The seal according to the invention has the following advantages. 
   It allows a secure identification for each object to which it is affixed. 
   The installation of the seal device may be validated by interrogation of a transponder. 
   The sealed object and its merchandise may be monitored throughout the journey by interrogation of the transponders and transmission of the information. Specifically, the information, such as the identification codes, may be read as many times as necessary since this is done without removing or damaging the seal device and, consequently without harming its integrity. 
   The integrity of the device may be inspected at any location, either directly when the transponder does not respond, or by comparison with the identification code or codes read on site and compared with those originally entered in a database that can be accessed on line when the device has been replaced without authorization. It is then possible, by analyzing the data entered in the permanent transponder, to determine, where necessary, the person responsible, the location and the date of the unauthorized handling. 
   When the transponder circuit comprises programmable or encryptable means, it is possible to encode or encrypt the data stored in the seal, thereby providing an enhanced level of security. 
   The seal device has a low production cost. 
   The seal device has a good mechanical strength which means that it can be used with objects being transported such as containers that are often handled without particular care.