EP2590154A1

EP2590154A1 - Secure sealing device

Info

Publication number: EP2590154A1
Application number: EP11187485.5A
Authority: EP
Inventors: Sameer Mubarak
Original assignee: Nafith Logistics Psc
Current assignee: Nafith Logistics Psc
Priority date: 2011-11-02
Filing date: 2011-11-02
Publication date: 2013-05-08

Abstract

The present invention concerns a secure sealing device (101) comprising a radiofrequency transceiver (105) with a first antenna (106), a closure element (102), a second antenna (107) with a higher gain than the first antenna (106) at a transmission frequency of the radiofrequency transceiver (105). The closure element (102) presents an electrically conductive path (108) for connecting the radiofrequency transceiver (105) to the second antenna (107) in a closed state of the secure sealing device (101). The present invention also relates to a secure sealing method wherein access to a sealed content is prevented by the closure element (102), so that breaking said closure element (102) to gain access to the sealed content will disconnect the radiofrequency transceiver (105) from the second antenna (107), substantially reducing the range of the radiofrequency transceiver (105).

Description

TECHNICAL FIELD

The invention relates to the domain of secure sealing devices and methods, in particular those involving radiofrequency transceivers.

BACKGROUND

It has been a long-standing human necessity to seal access to certain assets, in particular assets in transit. In order to prevent smuggling, for instance, customs authorities routinely seal in-transit cargo vehicles and shipping containers with tagged sealing devices. Such tagged sealing devices may also be used by cargo owners or logistics providers to protect cargo against theft or other unauthorized tampering. While the physical protection offered by such tagged sealing devices may be limited, their main purpose is to clearly reveal whether they have been breached and the cargo potentially accessed. By regularly checking the tagged sealing devices, the cargo can be tracked and, if the sealing device has been breached, it is possible to identify the transit segment during which the breach has taken place. Such tagged sealing devices can thus be very efficient deterrents against unauthorized access, diversion and/or tampering of assets in transit.
Different types of tagged sealing devices are known to the skilled person. In one of its simplest forms, such a tagged sealing device may be a plastic tag with a ratchet strap. More elaborate tagged sealing devices take the form of a metal lock with a wire strap, a tagged metal strip seal, or a tagged bolt seal. To prevent false alerts, it is also important to prevent accidental breaches of such tagged sealing devices. To this purpose, the International Standard Organization (ISO) has issued the ISO 17712 standard for Tensile, Shear, Bend and Impact Resistance certification for sealing devices.
One inconvenient of most such tagged sealing devices is that checking and identifying them requires close visual inspection of the tags. When large numbers of containers have to be tracked, for instance in important customs checkpoints or transshipment facilities, this can be extremely tedious and time-consuming. Moreover, agents visually inspecting large numbers of seals may easily overlook individual seal breaches.
For this reason, several different types of secure sealing devices have been proposed incorporating radiofrequency identification (RFID) technology. Such RFID devices incorporate a radiofrequency transceiver for wirelessly communicating identification data to a remote reader. Moreover, the radiofrequency transceiver may also transmit a specific signal if the sealing device has been breached. For instance US Patent Application Publications US 2005/0231365 A1 and US 2007/0103310 A1 and US Patent US 6,265,973 B1 each disclose a secure sealing device with an electronic circuit configured to transmit a specific signal in case of breach. However, the secure sealing devices disclosed in these documents require active radiofrequency transceivers, and thus a power supply. Ensuring such a power supply increases the complexity and cost of these sealing devices and reduces their reliability.
Alternative, secure sealing devices have also been proposed that only require a passive radiofrequency transceiver, that is, a transceiver that can be powered solely by the energy of incoming radio signals. One such device is disclosed in US Patent Application Publication US 2006/0145868 A1 . In this secure sealing device, the connection between the radiofrequency transceiver and its antennas is broken if the seal is breached. Such a breach can therefore be easily detected. However, no other means for reading information stored in the radiofrequency transceiver are disclosed, so that such potentially useful information may be lost after the breach, or at least require close inspection of the sealing device. Moreover, this device has a significant mechanical complexity.
Similarly, US Patent Application Publication US 2006/0087431 A1 discloses a secure sealing device comprising a radiofrequency transceiver with an antenna, and a closure element. The radiofrequency transmitter is passive and the closure element presents an electrically conductive path for connecting the radiofrequency transceiver to the antenna, so that, if the closure element is severed, the connection between the radiofrequency transceiver and the antenna is interrupted, and communication with the radiofrequency transceiver no longer possible. While this facilitates remote detection of a seal breach, it does not provide for an easy extraction of potentially useful data from the radiofrequency transmitter after this breach.

SUMMARY

A first object of the disclosure is that of providing a simple secure sealing device which can be wirelessly inspected for breaches and still provide useful tracking information after the breach.
Accordingly, in at least one illustrative embodiment, this secure sealing device comprises at least a radiofrequency transceiver with a first antenna, a closure element, and a second antenna with a higher gain than the first antenna at a transmission frequency of the radiofrequency transceiver, wherein that the closure element presents an electrically conductive path for connecting the radiofrequency transceiver to the second antenna in a closed state of the secure sealing device.
Consequently, since breaking the closure element will interrupt the electrically conductive path connecting the radiofrequency transceiver to the second, higher gain antenna, the range of the radiofrequency transmitter is substantially reduced. A breach of the secure sealing device will thus be easily detected by long-range readers, while it will still be possible to communicate with the radiofrequency transmitter at a closer range. So, for instance, when such a secure sealing device is used to seal the cargo doors of a truck or shipping container, routine inspections can be carried out using portal readers, and, if the secure sealing device fails to respond to the portal reader because of a breach, a handheld reader can still be used to extract detailed tracking data from the secure sealing device. Furthermore, a final visual inspection can also take place before an authorized person breaks the closure element to open the secure sealing device.
In particular, the secure sealing device may further comprise a locking body containing the radiofrequency transceiver and the first and second antennas, and adapted to irreversibly connect a first and a second end of the closure element. This particular configuration helps ensure that the secure sealing device can only be breached at the closure element, which will interrupt the connection of the radiofrequency transceiver to the second antenna. At least the radiofrequency transceiver and first antenna may be encapsulated within the locking body for protection, so that the close-range communication with the radiofrequency transceiver can be preserved.
In a particularly simple arrangement, the first end of the closure element may be fixedly connected to the locking body. To close the secure sealing device, it will thus be enough to connect the second end of the closure element to the locking body, which facilitates handling the secure sealing device. In this particular case, the closure element may even be integrally formed with the locking body, which also facilitates production of the secure sealing device.
In particular, the locking body may comprise an electric connector for connecting said electrically conductive path to the second antenna in said closed state of the secure sealing device. Closing the secure sealing device thus closes the connection of the radiofrequency transceiver to the antenna.
According to a first alternative, the electrically conductive path may form a loop on said closure element that starts and ends at the same end of the closure element. In particular if the closure element is integrally formed with a locking body containing the radiofrequency transceiver and both the first and second antennas, this helps dispense with electric connectors. However, according to a second alternative, the electrically conductive path may start at a first end of the closure element and end at a second end of the closure element. With this second alternative, said electrically conductive path may be formed by the whole of the closure element, for instance when the closure element is a metallic cord, or may comprise a conductive coating on an outer surface of the closure element.
However, the electrically conductive path may instead be printed on a non-conductive substrate of the closure element, which facilitates production. To prevent the repair of any tampering, the electrically conductive path may in particular be embedded in the closure element.
In particular, the closure element may be elongated and flexible. For instance, it may be a plastic ratchet strap or a cord. This would give the secure sealing element a great flexibility of use, making it adaptable for sealing a variety of closures.
In particular, the radiofrequency transceiver may comprise a processor and a memory. Tracking data may thus be stored in this memory, and both an incoming signal from a reader and the stored data may be processed before replying to the signal, for instance to ensure confidentiality of the tracking data using access authorization and encryption techniques. Said memory may be a read-only or a rewritable memory, in which second case the tracking data may be regularly updated.
In particular, the radiofrequency transceiver may be a passive radiofrequency transceiver, that is, powered only by the energy of incoming radiofrequency signals. An independent power supply can thus be dispensed with, increasing the reliability and reducing the cost of the secure sealing device. However, in certain circumstances, the use of active radiofrequency transceivers, that is, battery-powered radiofrequency transceivers that may broadcast or beacon a signal independently of incoming signals, or of battery-assisted passive radiofrequency transceivers, which only broadcast or beacon a signal in response to a corresponding incoming signal, may alternatively be considered. In this context, other power sources, such as, for example, photovoltaic cells, may also be considered alternatively or in combination with batteries.
Besides the radiofrequency transceiver, the secure sealing device may also comprise a visible identification marking, such as, for instance, an identification code, in the form of a laser-printed alphanumeric sequence and/or bar code, or a hologram. This visible identification marking can thus supplement the information transmitted by the radiofrequency transceiver upon close visual inspection.
Another object of the disclosure is that of providing an affordable and reliable secure sealing method. In this secure sealing method, access to a sealed content is prevented by a closure element presenting an electrically conductive path, and a radiofrequency transceiver connected to a first antenna is also connected, through said electrically conductive path, to a second antenna having a higher gain than the first antenna at a transmission frequency of the radiofrequency transceiver. Breaking the closure element to gain access to the sealed content will interrupt the electrically conductive path between the radiofrequency and the second antenna, substantially reducing the range of the radiofrequency transceiver.
The above summary of some example embodiments is not intended to describe each disclosed embodiment or every implementation of the invention. In particular, selected features of any illustrative embodiment within this specification may be incorporated into an additional embodiment unless clearly stated to the contrary.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which :

FIG. 1A is a perspective view of a secure sealing device according to a first embodiment of the present invention ;
FIG. 1B is a cutaway perspective view of the secure sealing device of FIG. 1A ;
FIG. 2A is a perspective view of a secure sealing device according to a second embodiment of the present invention ;
FIG. 2B is a cutaway perspective view of the secure sealing device of FIG. 2A.

While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.
As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.
The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The detailed description and the drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the invention. The illustrative embodiments depicted are intended only as exemplary. Selected features of any illustrative embodiment may be incorporated into an additional embodiment unless clearly stated to the contrary.
A secure sealing device 101 according to a first embodiment of the present invention is illustrated in FIGS. 1A and 1B. As can be seen in FIG. 1A, this secure sealing device 101 comprises a closure element 102 in the form of a plastic ratchet strap, and a locking body 103 integrally formed with the closure element 102. The locking body 103 is fixedly connected to a first end 102a of the closure element 102, and presents an orifice 104 for receiving the opposite second end 102b of the closure element 102 in order to close the secure sealing device 101. The orifice 104 and the ratchet teeth 102c on the surface of the closure element 102 are shaped so as to allow the introduction of the closure element 102 into the orifice 104 in one direction, but then prevent its retreat in the opposite direction. As illustrated in FIG. 1A, the area around the orifice 104 can be reinforced to ensure that, under a pulling force, the closure element 102 will break before this irreversible connection between the lock body 103 and the second end 102b of the closure element 102.
In the illustrated embodiment, the lock body 103 forms a tag which can present visible markings (not shown), in the form, for instance, of alphanumeric codes, bar codes, or other human- or machine-readable codes, printed or embossed, or of other authentication or identification markings, such as, for instance, holograms.
However, as illustrated in the cutaway view of FIG. 1B, the secure sealing device 101 also comprises, embedded within the locking body 103, a radiofrequency transceiver 105 with at least one transmission frequency, a first antenna 106, and a second antenna 107. The radiofrequency transceiver 105 is a passive radiofrequency transceiver in the form of a passive RFID microchip, compliant with ISO/IEC 18000, and comprising a processor and a memory. The transmission frequencies of this passive RFID microchip may be, for instance, 2.45 GHz, as specified under ISO/IEC 18000-4, 860-960 MHz, as specified under ISO/IEC 18000-6, and/or 433 MHz, as specified under ISO/IEC 18000-7. The memory can be a read-only or a rewritable memory, wherein a rewritable memory could store information received by the radiofrequency transceiver 105, such as, for instance, itinerary information collected at each reading of the radiofrequency transceiver 105. The first and second antennas are flat meander antennas, wherein the first antenna 106 is directly connected to the radiofrequency transceiver 105, but the second antenna 107, on the other hand, is connected to the radiofrequency transceiver 105 through an electrically conductive path 108 in the closure member 102. This second antenna 107 has a higher gain, at said transmission frequency of the radiofrequency transceiver 105, than the first antenna 106. The electrically conductive path 108 forms a loop starting and ending at said first end 102a of the closure member 102.
Both antennas 106,107 and said electrically conductive path 108 can be printed together on a non-conductive substrate of the secure sealing device 101. This non-conductive substrate can be produced, for instance, in a first injection molding step, and the antennas 106, 107, electrically conductive path 108 and radiofrequency transceiver 105 can be safely encapsulated in a subsequent second injection molding step.
In use, the elongated, flexible closure member 102 can be threaded and looped around two adjacent elements closing an access to a content to be sealed, such as, for instance, lugs attached to respective wings of a door of a shipping container. The second end 102b of the closure member 102 is then threaded through the orifice 104, irreversibly connecting it to the locking body 103, and preventing the separation of the abovementioned two adjacent elements, so that access to the sealed content is effectively prevented unless the closure member 102 is broken.
As long as the closure member 102 remains intact, the radiofrequency transceiver 105 remains connected to the second, higher-gain antenna 107. The gain of this second antenna 107 at a transmission frequency of the radiofrequency transceiver 105 is such that the radiofrequency transceiver 105 can communicate with readers at several meters' distance. This allows, for instance, rapid wireless inspection of the seals of shipping containers and trucks by driving them through reader portals. If, however, the closure member 102 has been broken, the connection of the radiofrequency transceiver 105 with the second antenna 107 is interrupted, and the range of the radiofrequency transceiver 105 drastically reduced. In the abovementioned example, the portal reader will no longer be able to detect a response of the radiofrequency transceiver 105.
It must be noted that, because the electrically conductive path 108 is embedded within the closure member 102, it will normally not be possible to reliably re-establish this electrically conductive path 108 by repairing the broken closure member 102. If the radiofrequency transceiver 105 thus fails to respond to a reader at the normal long range, the sealed container may be pulled aside for closer inspection of the secure sealing device 101. Since the connection of the radiofrequency transceiver 105 to the first, lower-gain antenna 106 remains safely encapsulated within the locking body 103, it will still be possible to wirelessly extract information from the radiofrequency transceiver 105, using, for instance, a handheld reader. The visible markings in the locking body 103 can complement this information of the radiofrequency transceiver 105.
In some applications, a more robust secure sealing device may be desirable. In a secure sealing device 201 according to a second embodiment illustrated in FIGS. 2A and 2B, the closure element 202 is a cord, such as can be produced by winding together several strands of filaments, including at least one electrically conductive filament, and eventually consolidated with an adhesive. The locking body 203 presents a first part 203a comprising an electrically non-conductive substrate, and a metallic second part 203b. A first channel 211 and a second channel 212 each traverse both the first part 203a and the second part 203b. A first end 202a of the closure element 202 is fixed within the first channel 211, whereas the second channel 212 forms, within the second part 203b, an irreversible connector 204 with non-return spikes 204a for receiving a second end 202b of the closure element 202 to close the secure sealing device 201. Please note that in FIGS. 2A and 2B the secure sealing device 201 is shown in its closed state, unlike the secure sealing device 101 which was illustrated in an open state in FIGS. 1A and 1B.
As in the first embodiment, the lock body 203 can also present visible markings (not shown), in the form, for instance, of alphanumeric sequences, bar codes, or other human- or machine-readable codes, printed or embossed, or of other authentication or identification markings, such as, for instance, holograms.
As illustrated in the cutaway view of FIG. 2B, the secure sealing device 201 also comprises, embedded within the first part 203a of the locking body 203, a radiofrequency transceiver 205 with at least one transmission frequency, a first antenna 206, and a higher-gain second antenna 207. These radiofrequency transceiver 205, first antenna 206 and second antenna 207 are similar to those of the first embodiment, and the first antenna 206 is also directly connected to the radiofrequency transceiver 205. The first part 203a also contains a first electric connector 209 and a second electric connector 210, wherein the first electric connector 210 connects the radiofrequency transceiver 205 to the fixedly connected first end 202a of the closure element 202, and the second electric connector 209 is adapted to connect the second end 202b of closure element 202 to the second antenna 207 when it is irreversibly connected to the locking body 203. In the closed state of the secure sealing device 201, the at least one electrically conductive filament of this closure element 202 thus forms an electrically conductive path 208 between the first and second electric connectors 210,209, thus connecting the radiofrequency transceiver 205 to the second antenna 207. To improve the connection of this conductive path 208 to the first and second electric connectors 210,209, the closure element 202 may present a conductive coating at least locally. Both antennas 206,207 and both electric connectors 209,210 can be printed simultaneously on a non-conductive substrate of the secure sealing device 201.
As in the first embodiment, as long as the closure member 202 remains intact, the radiofrequency transceiver 205 remains connected to the second, higher-gain antenna 207. The radiofrequency transceiver 105 can thus communicate with readers at several meters' distance, allowing, as in the first embodiment, rapid wireless inspection of the seals of shipping containers and trucks by driving them through reader portals. If, however, the closure member 202 has been broken, the connection of the radiofrequency transceiver 205 with the second antenna 207 is interrupted, and the range of the radiofrequency transceiver 205 is also drastically reduced. If the radiofrequency transceiver 205 thus fails to respond to a reader at the normal long range, the sealed container may be pulled aside for closer inspection of the secure sealing device 201. Since the connection of the radiofrequency transceiver 205 to the first, lower-gain antenna 206 remains safely encapsulated within first part 203a of the locking body 203, it will still be possible to wirelessly extract information from the radiofrequency transceiver 205 from a smaller distance. As in the first embodiment, the visible markings in the locking body 203 can complement this information of the radiofrequency transceiver 205.
In an alternative embodiment, not illustrated and otherwise analogous to this second embodiment, the positions of the first and second parts 203a, 203b of the locking body 203 are switched, so that, in the closed position, the closure element 202 exits and reenters the locking body 203 through the first part 203a, rather than the second part 203b. This shortens the electrically conductive path 206 between the electric connectors 209,210, improving its conductivity and increasing the reliability of the secure sealing device 201.
Those skilled in the art will recognize that the present invention may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departure in form and detail may be made without departing from the scope of the present invention as described in the appended claims.

Claims

Secure sealing device (101,201) comprising at least :
a radiofrequency transceiver (105,205) with a first antenna (106,206) ; and

a closure element (102,202) ;
the secure sealing device (101,201) being characterized in that it further comprises a second antenna (107,207) with a higher gain than the first antenna (106,206) at a transmission frequency of the radiofrequency transceiver (105,205), and in that the closure element (102,202) presents an electrically conductive path (108,208) for connecting the radiofrequency transceiver (105,205) to the second antenna (107,207) in a closed state of the secure sealing device (101,201).
Secure sealing device (101,201) according to claim 1, further comprising a locking body (103,203) containing the radiofrequency transceiver (105,205) and the first and second antennas (106,206;107,207), and adapted to irreversibly connect a first and a second end (102a,102b) of the closure element (102,202).
Secure sealing device (101,201) according to claim 2, wherein the first end of the closure element (102,202) is fixedly connected to the locking body (103,203).
Secure sealing device (201) according to any one of claims 2 or 3, wherein said locking body (203) comprises an electric connector (209) for connecting said electrically conductive path (208) to the second antenna (207) in said closed state of the secure sealing device (201).
Secure sealing device (101) according to any one of the previous claims, wherein said electrically conductive path (108) forms a loop on said closure element (102) that starts and ends at the same end of the closure element (102).
Secure sealing device (201) according to any one of claims 1 to 4, wherein said electrically conductive path (208) starts at a first end of the closure element (202) and ends at a second end of the closure element (202).
Secure sealing device (201) according to claim 6, wherein said electrically conductive path (208) comprises a conductive coating on an outer surface of the closure element (202).
Secure sealing device (101) according to any one of the previous claims, wherein said electrically conductive path (108) is printed on a non-conductive substrate of the closure element (102).
Secure sealing device (101,201) according to any one of the previous claims, wherein the closure element (102,202) is elongated and flexible.
Secure sealing device (101) according to claim 9, wherein the closure element (102,202) is a plastic ratchet strap.
Secure sealing device (201) according to claim 9, wherein the closure element (202) is a cord.
Secure sealing device (101,201) according to any one of the previous claims, wherein said radiofrequency transceiver (105,205) comprises a processor and a memory.
Secure sealing device (101,201) according to any one of the previous claims, wherein said radiofrequency transceiver (105,205) is a passive radiofrequency transceiver.
Secure sealing device (101,201) according to any one of the previous claims, further comprising a visible identification marking.
Secure sealing method, wherein access to a sealed content is prevented by a closure element (102,202) presenting an electrically conductive path (108,208), and a radiofrequency transceiver (105,205) connected to a first antenna (106,206) is also connected, through said electrically conductive path (108,208), to a second antenna (107,207) having a higher gain than the first antenna (106,206) at a transmission frequency of the radiofrequency transceiver (105,205).