Electronic locking seal

Information

  • Patent Grant
  • 6778083
  • Patent Number
    6,778,083
  • Date Filed
    Tuesday, August 27, 2002
    22 years ago
  • Date Issued
    Tuesday, August 17, 2004
    20 years ago
Abstract
A tamper-resistant remotely monitorable electronic seal including a shaft portion, a socket arranged to engage the shaft portion in a monitorable manner, whereby disengagement of the socket and the shaft portion results in a monitorable event, and a wireless communicator associated with at least one of the shaft portion and the socket and being operative to provide a remotely monitorable indication of the monitorable event.
Description




FIELD OF THE INVENTION




The present invention relates to electronic seals generally and more particularly to tamper-resistant electronic seals.




BACKGROUND OF THE INVENTION




The following U.S. Patents are believed to be representative of the prior art:




U.S. Pat. Nos. 4,750,197, 5,056,837; 5,097,253, 5,127,687; 5,169,188; 5,189,396; 5,406,263, 5,421,177, 5,587,702; 5,656,996 and 6,069,563.




SUMMARY OF THE INVENTION




The present invention seeks to provide an improved electronic seal




There is thus provided in accordance with a preferred embodiment of the present invention a tamper-resistant remotely monitorable electronic seal including a shaft portion, a socket arranged to engage the shaft portion in a monitorable manner, whereby disengagement of the socket and the shaft portion results in a monitorable event, and a wireless communicator associated with at least one of the shaft portion and the socket and being operative to provide a remotely monitorable indication of the monitorable event. Preferably, the wireless communicator is a transceiver. Additionally, the shaft portion includes at least one conductive path which is interrupted in response to disengagement of the socket and the shaft portion and wherein the wireless communicator is operative to provide a remotely monitorable indication of the monitorable event.




In accordance with another preferred embodiment of the present invention, the shaft portion includes a frangible shaft portion having a press-fit tip, the socket includes a press-fit socket arranged to engage the press-fit tip in a destructably removable manner, whereby disengagement of the socket and the shaft portion results in breakage of the shaft portion, the at least one conductive path extends at least through the shaft portion and is breakable in response to breakage of the shaft portion, and the wireless communicator is associated with at least one of the shaft portion and the press-fit socket and is operative to provide a remotely monitorable indication of the integrity or lack of integrity of the at least one conductive path. Preferably, the at least one conductive path is defined by conductors extending through the shaft portion which are in electrical contact with a conductor formed in the press-fit socket when the shaft portion and the socket are in press-fit engagement. Additionally, the press-fit tip includes a toothed tip. Alternatively, the at least one conductive path includes at least one reed switch which is operated by a magnet associated with the socket whereby when the shaft portion is separated from the socket for any reason, the at least one conductive path is broken.




In accordance with yet another preferred embodiment of the present invention, the shaft portion includes a frangible shaft portion having a lockable portion, the socket includes a locking element arranged to engage the lockable portion in a destructably removable manner, whereby disengagement of the locking element and the shaft portion results in breakage of the shaft portion, the at least one conductive path extends at least through the shaft portion and is breakable in response to breakage of the shaft portion, and the wireless communicator is associated with at least one of the shaft portion and the socket and is operative to provide a remotely monitorable indication of the integrity or lack of integrity of the at least one conductive path. Preferably, the shaft portion includes a groove adaptable for lockable engagement with the locking element. Additionally, the at least one conductive path includes at least one reed switch which is operated by a magnet associated with the socket whereby when the shaft portion is separated from the socket for any reason, the at least one conductive path is broken.




In accordance with a further preferred embodiment of the present invention, the communicator is located in a sensing circuitry and communicator housing integrally formed with the shaft portion. Preferably, the frangible shaft portion includes at least one frangible location having relatively weak mechanical strength as compared with other portions of the shaft portion.











BRIEF DESCRIPTION OF THE DRAWINGS




The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:





FIGS. 1A and 1B

are simplified pictorial illustrations of two stages in the assembly of a press-fit electronic seal constructed and operative in accordance with a preferred embodiment of the present invention;





FIGS. 2A and 2B

are simplified pictorial illustrations of two different types of breaks produced in the press-fit electronic seal of

FIGS. 1A and 1B

;





FIGS. 3A and 3B

are simplified pictorial illustrations of two stages in the assembly of a lockable electronic seal constructed and operative in accordance with a preferred embodiment of the present invention;





FIGS. 4A and 4B

are simplified pictorial illustrations of two different types of breaks produced in the lockable electronic seal of

FIGS. 3A and 3B

;





FIGS. 5A and 5B

are simplified pictorial illustrations of two stages in the assembly of a press-fit electronic seal constructed and operative in accordance with another preferred embodiment of the present invention;





FIGS. 6A and 6B

are simplified pictorial illustrations of two different types of breaks produced in the press-fit electronic seal of

FIGS. 5A and 5B

;





FIGS. 7A and 7B

are simplified pictorial illustrations of two stages in the assembly of a lockable electronic seal constructed and operative in accordance with another preferred embodiment of the present invention; and





FIGS. 8A and 8B

are simplified pictorial illustrations of two different types of breaks produced in the lockable electronic seal of

FIGS. 7A and 7B

.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




Reference is now made to

FIGS. 1A and 1B

, which are simplified pictorial illustrations of two stages in the assembly of a press-fit electronic seal constructed and operative in accordance with a preferred embodiment of the present invention.




As seen in

FIGS. 1A and 1B

, there is provided a tamper-resistant electronic seal which preferably comprises a shaft portion


10


, which is integrally formed with or fixed to a sensing circuitry and transceiver portion


12


Shaft portion


10


preferably has a generally cylindrical configuration and terminates in a press-fit tip


14


, preferably formed with a series of circumferential teeth


16


which are adapted for press-fit engagement with corresponding tooth-like recesses formed in a socket


18


. The press-fit engagement between tip


14


of shaft portion


10


and socket


18


is preferably such that it is impossible to remove the tip


14


from the socket


18


without breaking the shaft portion


10


.




Shaft portion


10


preferably includes a weakened frangible portion


20


, located intermediate the sensing circuitry and transceiver portion


12


and the tip


14


. Frangible portion


20


is preferably located closer to sensing circuitry and transceiver portion


12


than to tip


14


and typically has a lesser thickness than the remainder of the shaft portion


10


.




A conductive loop


22


preferably extends through shaft portion


10


through to the tip


14


thereof and is configured and mounted in shaft portion


10


, such that breakage of the shaft portion


10


produces a disconnection or significant change in the electrical properties of the conductive loop


22


.




In accordance with a preferred embodiment of the present invention, sensing circuitry


23


and an RF transceiver


24


are housed within sensing circuitry and transceiver portion


12


Sensing circuitry


23


is electrically coupled to conductive loop


22


and senses the integrity thereof Receiving an output from sensing circuitry


23


is transceiver


24


, which is operative to provide transmitted information indicating whether the conductive loop


22


is intact. Conventional wireless monitoring circuitry (not shown) may be employed to receive information which is transmitted by RF transceiver


24


and indicates tampering with the seal which results in breakage of the shaft portion


10


.




Reference is now made to

FIGS. 2A and 2B

, which are simplified pictorial illustrations of two different types of breaks produced in the press-fit electronic seal of

FIGS. 1A and 1B

. As noted above, application of force to the seal of

FIGS. 2A and 2B

in an attempt to separate shaft portion


10


from socket


18


will not cause tip


14


to be disengaged from socket


18


, without first breaking the shaft portion


10


.

FIG. 2A

shows such a break at a location along the shaft portion


10


which lies just above the tip


14


. It is seen that this break produces a disconnection or significant change in the electrical properties of the conductive loop


22


.





FIG. 2B

shows such a break at the frangible portion


20


along the shaft portion


10


It is seen that this break also produces a disconnection or significant change in the electrical properties of the conductive loop


22


.




Reference is now made to

FIGS. 3A and 3B

, which are simplified pictorial illustrations of two stages in the assembly of a lockable electronic seal constructed and operative in accordance with a preferred embodiment of the present invention.




As seen in

FIGS. 3A and 3B

, there is provided a tamper-resistant reusable lockable electronic seal which preferably comprises a shaft portion


30


, which is integrally formed with or fixed to a sensing circuitry and transceiver portion


32


Shaft portion


30


preferably has a generally cylindrical configuration and terminates in a lockable tip


34


, preferably formed with an undercut groove


36


which is adapted for lockable engagement with a corresponding locking element


38


forming part of a lock


40


, defining a socket, which includes a magnet


41


. Lock


40


is here shown to be a key-operated lock, it being appreciated that any other suitable type of lock may be employed. The locking engagement between tip


34


of shaft portion


30


and locking element


38


Is preferably such that without first unlocking the lock, it is impossible to remove the tip


34


from engagement with the locking element


38


without breaking the shaft portion


30


.




Shaft portion


30


preferably includes a weakened frangible portion


42


, located intermediate the sensing circuitry and transceiver portion


32


and the tip


34


. Frangible portion


42


is preferably located closer to sensing circuitry and transceiver portion


32


than to tip


34


and typically has a lesser thickness than the remainder of the shaft portion


30


.




A conductive loop


44


, including a series connected reed switch


45


which is closed by magnet


41


when shaft portion


30


is in lockable engagement with lock


40


, preferably extends through shaft portion


30


through to the tip


34


thereof and is configured and mounted in shaft portion


30


, such that breakage of the shaft portion


30


produces a disconnection or significant change in the electrical properties of the conductive loop


44


.




In accordance with a preferred embodiment of the present invention, sensing circuitry


46


and an RF transceiver


48


are housed within sensing circuitry and transceiver portion


32


. Sensing circuitry


46


is electrically coupled to conductive loop


44


and senses the integrity thereof. Receiving an output from sensing circuitry


46


is transceiver


48


, which is operative to provide transmitted information indicating whether the conductive loop


44


is intact. Conventional wireless monitoring circuitry (not shown) may be employed to receive information which is transmitted by RF transceiver


48


and indicates when the shaft portion


30


is located in lockable engagement with lock


40


and when the shaft portion


30


is separated from lock


40


due to either tampering with the seal, which results in breakage of the shaft portion


30


, or disengagement of shaft portion


30


and lock


40


by using a key to unlock lock


40


It is appreciated that the provision of reed switch


45


and magnet


41


enables sensing circuitry


46


to sense when the shaft portion


30


is located in lockable engagement with lock


40


and when the shaft portion


30


is separated from lock


40


for any reason, and allows for recording of engagements and disengagements of shaft portion


30


and lock


40


.




Reference is now made to

FIGS. 4A and 4B

, which are simplified pictorial illustrations of two different types of breaks produced in the lockable electronic seal of

FIGS. 3A and 3B

As noted above, application of force to the seal of

FIGS. 4A and 4B

in an attempt to separate shaft portion


30


from locking element


38


will not cause tip


34


to be disengaged from locking element


38


, without first breaking the shaft portion


30



FIG. 4A

shows such a break at a location along the shaft portion


30


which lies just above the tip


34


. It is seen that this break produces a disconnection or significant change in the electrical properties of the conductive loop


44


.





FIG. 4B

shows such a break at the frangible portion


42


along the shaft portion


30


. It is seen that this break also produces a disconnection or significant change in the electrical properties of the conductive loop


44


.




It is appreciated that the reed switch and magnet shown in the illustrated embodiments of

FIGS. 3A-4B

can also be used in the embodiments of

FIGS. 1A-2B

.




Reference is now made to

FIGS. 5A and 5B

, which are simplified pictorial illustrations of two stages in the assembly of a press-fit electronic seal constructed and operative in accordance with another preferred embodiment of the present invention.




As seen in

FIGS. 5A and 5B

, there is provided a tamper-resistant electronic seal which preferably comprises a shaft portion


50


, which is integrally formed with or fixed to a sensing circuitry and transceiver portion


52


Shaft portion


50


preferably has a generally cylindrical configuration and terminates in a press-fit tip


54


, preferably formed with a series of circumferential teeth


56


which are adapted for press-fit engagement with corresponding tooth-like recesses formed in a socket


58


. The press-fit engagement between tip


54


of shaft portion


50


and socket


58


is preferably such that it is impossible to remove the tip


54


from the socket without breaking the shaft portion


50


.




Shaft portion


50


preferably includes a weakened frangible portion


60


, located intermediate the sensing circuitry and transceiver portion


52


and the tip


54


. Frangible portion


60


is preferably located closer to sensing circuitry and transceiver portion


52


than to tip


54


and typically has a lesser thickness than the remainder of the shaft portion


50


.




A pair of elongate conductors


62


and


64


preferably extends through shaft portion


50


through to the tip


54


thereof and is configured and mounted in shaft portion


50


, such that breakage of the shaft portion


50


produces a disconnection or significant change in the electrical properties of at least one and preferably both of conductors


62


and


64


. Preferably, conductors


62


and


64


communicate with respective contacts


66


and


68


which are exposed at the end of tip


54


and are arranged to electrically engage an electrical shorting contact


70


at the corresponding interior surface of socket


58


when shaft portion


50


is fully press-fit mounted into socket


58


, thereby defining a conductive loop.




In accordance with a preferred embodiment of the present invention, sensing circuitry


71


and an RF transceiver


72


are housed within sensing circuitry and transceiver portion


52


. Sensing circuitry


71


is electrically coupled to conductors


62


and


64


and senses the integrity of a conductive loop which is defined by conductors


62


and


64


when the shaft portion


50


is fully seated in socket


58


. Receiving an output from sensing circuitry


71


is transceiver


72


, which is operative to provide transmitted information indicating whether the conductive loop is intact. Conventional wireless monitoring circuitry (not shown) may be employed to receive information which is transmitted by RF transceiver


72


and indicates tampering with the seal which results in breakage of the shaft portion


50


.




Reference is now made to

FIGS. 6A and 6B

, which are simplified pictorial illustrations of two different types of breaks produced in the press-fit electronic seal of

FIGS. 5A and 5B

As noted above, application of force to the seal of

FIGS. 6A and 6B

in an attempt to separate shaft portion


50


from socket


58


will not cause tip


54


to be disengaged from socket


58


, without first breaking the shaft portion


50



FIG. 6A

shows such a break at a location along the shaft portion


50


which lies just above the tip


54


. It is seen that this break produces a disconnection or significant change in the electrical properties of the conductive loop defined by conductors


62


and


64


.





FIG. 6B

shows such a break at the frangible portion


60


along the shaft portion


50


. It is seen that this break also produces a disconnection or significant change in the electrical properties of the conductive loop.




Reference is now made to

FIGS. 7A and 7B

, which are simplified pictorial illustrations of two stages in the assembly of a lockable electronic seal constructed and operative in accordance with another preferred embodiment of the present invention.




As seen in

FIGS. 7A and 7B

, there is provided a tamper-resistant lockable electronic seal which preferably comprises a shaft portion


80


, which is integrally formed with or fixed to a sensing circuitry and transceiver portion


82


. Shaft portion


80


preferably has a generally cylindrical configuration and terminates in a lockable tip


84


, preferably formed with an undercut groove


86


which is adapted for lockable engagement with a corresponding locking element


88


forming part of a lock


90


, defining a socket, which includes a magnet


91


. Lock


90


is here shown to be a key-operated lock, it being appreciated that any other suitable type of lock may be employed. The locking engagement between tip


84


of shaft portion


80


and locking element


88


is preferably such that without first unlocking the lock, it is impossible to remove the tip


84


from engagement with the locking element


88


without breaking the shaft portion


80


.




Shaft portion


80


preferably includes a weakened frangible portion


92


, located intermediate the sensing circuitry and transceiver portion


82


and the tip


84


. Frangible portion


92


is preferably located closer to sensing circuitry and transceiver portion


82


than to tip


84


and typically has a lesser thickness than the remainder of the shaft portion


80


.




A pair of elongate conductors


94


and


96


, at least one of which includes a series connected reed switch


98


which is closed by magnet


91


when shaft portion


80


is in lockable engagement with lock


90


, extends through shaft portion


80


through to the tip


84


thereof and is configured and mounted in shaft portion


80


, such that breakage of the shaft portion


80


produces a disconnection or significant change in the electrical properties of at least one and preferably both of conductors


94


and


96


. Preferably, conductors


94


and


96


communicate with respective contacts


102


and


104


which are exposed at the end of tip


84


. Contacts


102


and


104


are arranged to electrically engage an electrical shorting contact


106


at the corresponding interior surface of lock


90


when shaft portion


80


is in lockable engagement with lock


90


. This electrical engagement, together with the closing of series connected reed switch


98


by magnet


91


, thereby defines a conductive loop.




In accordance with a preferred embodiment of the present invention, sensing circuitry


108


and an RF transceiver


110


are housed within sensing circuitry and transceiver portion


82


. Sensing circuitry


108


is electrically coupled to conductors


94


and


96


and senses the integrity of a conductive loop which is defined by conductors


94


and


96


when the shaft portion


80


is in lockable engagement with lock


90


. Receiving an output from sensing circuitry


108


is transceiver


110


, which is operative to provide transmitted information indicating whether the conductive loop is intact. Conventional wireless monitoring circuitry (not shown) may be employed to receive information which is transmitted by RF transceiver


110


and indicates when the shaft portion


80


is located in lockable engagement with lock


90


and when the shaft portion


80


is separated from lock


90


due to either tampering with the seal, which results in breakage of the shaft portion


80


, or disengagement of shaft portion


80


and lock


90


by using a key to unlock lock


90


It is appreciated that the provision of reed switch


98


and magnet


91


enables sensing circuitry


108


to sense when the shaft portion


80


is located in lockable engagement with lock


90


and also enables sensing circuitry


108


to sense when the shaft portion


80


is separated from lock


90


for any reason, and allows for recording of engagements and disengagements of shaft portion


80


and lock


90






Reference is now made to

FIGS. 8A and 8B

, which are simplified pictorial illustrations of two different types of breaks produced in the lockable electronic seal of

FIGS. 7A and 7B

As noted above, application of force to the seal of

FIGS. 8A and 8B

in an attempt to separate shaft portion


80


from locking element


88


will not cause tip


84


to be disengaged from locking element


88


, without first breaking the shaft portion


80



FIG. 8A

shows such a break at a location along the shaft portion


80


which lies just above the tip


84


It is seen that this break produces a disconnection or significant change in the electrical properties of the conductive loop defined by conductors


94


and


96


.





FIG. 8B

shows such a break at the frangible portion


92


along the shaft portion


80


It is seen that this break also produces a disconnection or significant change in the electrical properties of the conductive loop defined by conductors


94


and


96


.




It is appreciated that the reed switch and magnet shown in the illustrated embodiments of

FIGS. 7A-8B

can also be used in the embodiments of

FIGS. 5A-6B

.




It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove as well as variations and modifications which would occur to persons skilled in the art upon reading the specification and which are not in the prior art.



Claims
  • 1. A tamper-resistant remotely monitorable electronic seal comprising;a shaft portion including at least one conductive path; a socket arranged to engage said shaft portion in a monitorable manner, whereby disengagement of said socket and said shaft portion results in a monitorable event; and a wireless communicator associated with at least one of said shaft portion and said socket and being operative to provide a remotely monitorable indication of said monitorable events, said at least one conductive path being interrupted in response to disengagement of said socket and said shaft portion, and said shaft portion and said at least one conductive path being breakable in response to disengagement of said socket and said shaft portion.
  • 2. A tamper-resistant remotely monitorable electronic seal according to claim 1 and wherein:said shaft portion comprises a frangible shaft portion having a press-fit tip; said socket comprises a press-fit socket arranged to engage said press-fit tip in a destructably removable manner, whereby disengagement of said socket and said shaft portion results in breakage of said shaft portion; said at least one conductive path extends at least through said shaft portion and is breakable in response to breakage of said shaft portion; and said wireless communicator is associated with at least one of said shaft portion and said press-fit socket and is operative to provide a remotely monitorable indication of the integrity or lack of integrity of said at least one conductive path.
  • 3. A tamper-resistant remotely monitorable electronic seal according to claim 2 and wherein said at least one conductive path is defined by conductors extending through said shaft portion which are in electrical contact with a conductor formed in said press-fit socket when said shaft portion and said socket are in press-fit engagement.
  • 4. A tamper-resistant remotely monitorable electronic seal according to claim 2 and wherein said communicator is located in a sensing circuitry and communicator housing integrally formed with said shaft portion.
  • 5. A tamper-resistant remotely monitorable electronic seal according to claim 2 and wherein said frangible shaft portion comprises at least one frangible location having relatively weak mechanical strength as compared with other portions of the shaft portion.
  • 6. A tamper-resistant remotely monitorable electronic seal according to claim 2 and wherein said press-fit tip comprises a toothed tip.
  • 7. A tamper-resistant remotely monitorable electronic seal according to claim 2 and wherein said at least one conductive path comprises at least one reed switch which is operated by a magnet associated with said socket whereby when said shaft portion is separated from said socket for any reason, said at least one conductive path is broken.
  • 8. A tamper-resistant remotely monitorable electronic seal according to claim 1 and wherein:said shaft portion comprises a frangible shaft portion having a lockable portion; said socket comprises a locking element arranged to engage said lockable portion in a destructably removable manner, whereby disengagement of said locking element and said shaft portion results in breakage of said shaft portion; said at least one conductive path extends at least through said shaft portion and is breakable in response to breakage of said shaft portion; and said wireless communicator is associated with at least one of said shaft portion and said socket and is operative to provide a remotely monitorable indication of the integrity or lack of integrity of said at least one conductive path.
  • 9. A tamper-resistant remotely monitorable electronic seal according to claim 8 and wherein said at least one conductive path comprises at least one reed switch which is operated by a magnet associated with said socket whereby when said shaft portion is separated from said socket for any reason, said at least one conductive path is broken.
  • 10. A tamper-resistant remotely monitorable electronic seal according to claim 8 and wherein said at least one conductive path comprises at least one reed switch which is operated by a magnet associated with said socket whereby when said shaft portion is separated from said socket for any reason, said at least one conductive path is broken,and is defined by conductors extending through said shaft portion and which are in electrical contact with a conductor formed in said socket when said shaft portion and said socket are in lockable engagement.
  • 11. A tamper-resistant remotely monitorable electronic seal according to claim 8 and wherein said communicator is located in a sensing circuitry and communicator housing integrally formed with said shaft portion.
  • 12. A tamper-resistant remotely monitorable electronic seal according to claim 8 and wherein said frangible shaft portion comprises at least one frangible location having relatively weak mechanical strength as compared with other portions of said shaft portion.
  • 13. A tamper-resistant remotely monitorable electronic seal according to claim 8 and wherein said shaft portion comprises a groove adaptable for lockable engagement with said locking element.
  • 14. A tamper-resistant remotely monitorable electronic seal according to claim 1 and wherein said wireless communicator is a transceiver.
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