IL125644A - Electronic sack seal - Google Patents

Abstract

An electronic seal comprising: a portable housing (12); alarm circuitry which when actuated provides an alarm signal; a wire (16) extending from said housing and in electrical communication with said alarm circuitry, whereby tampering with said wire causes actuation of said alarm circuitry; a locking element (40) which selectively lockingly engages said wire to said housing; and a wireless communication device (44) for wirelessly communicating the alarm signal. 669 כ" א באייר התשס" ד - May 12, 2004

Description

ELECTRONIC SACK SEAL Hi - G - Tek Ltd. o'oa pv> .»n C: 31349 FIELD OF THE INVENTION The present invention relates to electronic seals generally, and particularly to electronic seals for tying sacks and the like.

BACKGROUND OF THE INVENTION It is very common to close sacks, bags and the like by tying them with rope, cord: string, wire, etc., and then seal the tie with some type of inspector's seal which provides an indication of tampering with the seal. Such seals are generally mechanical in nature, such as the familiar lead seal lug on electrical meters, or quality assurance decals on the lids of electronic equipment.

It is known to attach to an object an electronic tag that can be monitored, sensed, or interrogated for purposes of preventing theft of or tampering with the object. For example, applicant/ ssignee's U. S. Patent No . 6 , 002 , 343 , the disclosure of which is incorporated herein by reference, describes a battery-operated electronic tag that, when tampered with, communicates via a transceiver to a detection system for providing an alarm signal or other indication, and thereby detect the tampering and/or removal of the tag from a tagged object.

However, electronic seals have not been used in the an for sealing sacks. Although one of the electronic seals described in U.S. Patent No . 6 , 002 , 343 employs resistive wires which when tampered with provide an indication of such tampering, nevertheless these wires are not readily applicable for providing a tampering indication when tied to a sack. One of the reasons is that the wires have a fixed length and after tying there is a portion of the wires which is inevitably left loose or dangling. If any portion of the wire is tampered with, dangling or not, an alarm will be sounded. However, in general, the alarm will be indicative of an actual attempt to break into the sack only if the part of the wire that is wrapped around and actually sealing the sack is tampered with. On the other hand, tampering with the dangling part is not necessarily indicative of an attempt to pilfer or tamper with the contents of the sack, and thus would constitute a false alarm.

There is thus a need for an electronic seal which can be used to seal a sack and the like and provide a true tampering indication thereof.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved electronic seal which can be used to seal a sack and the like and provide a true tampering indication thereof.

There is thus provided in accordance with a preferred embodiment of the present invention an electronic seal including a housing including alarm circuitry, the alarm circuitry when actuated providing an alarm signal, a wire extending from the housing and in electrical communication with the alarm circuitry, the wire being attached at a first point and at a second point thereof to the housing, a portion of the wire between the first and second points, called a tying portion, being suitable for tying an object, wherein tampering with the tying portion actuates the alarm circuitry, and an adjustment device for adjusting a length of the tying portion.

In accordance with a preferred embodiment of the present invention the adjustment device includes a yoke for wrapping therearound the tying portion.

Further in accordance with a preferred embodiment of the present invention an electrical element is disposed through the yoke, the electrically element being in electrical communication with the alarm circuitry, wherein a change in an electrical parameter of the electrical element is communicated to the alarm circuitry for actuation thereof.

Still further the adjustment device includes a tightening device to which the wire is attached, the tightening device permitting the wire to be drawn out of and to be pulled into the housing, and substantially fixing the wire at the second point thereof. Preferably the tightening device includes a locking element which selectively lockingly engages the wire.

Additionally in accordance with a preferred embodiment of the present invention the tightening device includes a bobbin around which the wire is wound and a locking element which selectively lockingly engages the bobbin.

In accordance with a preferred embodiment of the present invention a portion of the wire forms part of a Wheatstone bridge, in electrical communication with the alarm circuitry, for measuring changes in electrical resistance of the wire.

Additionally in accordance with a preferred embodiment of the present invention the first point is attached to an electrical connector in electrical communication with the alarm circuitry.

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: Fig. 1 is a simplified pictorial illustration of an electronic seal constructed and operative in accordance with a preferred embodiment of the present invention and comprising a yoke for wrapping therearound a wire; Fig. 2 is a simplified pictorial illustration of an electronic seal constructed and operative in accordance with another preferred embodiment of the present invention and comprising an extender yoke for wrapping therearound a wire; Fig. 3 is a simplified pictorial illustration of an electronic seal constructed and operative in accordance with yet another preferred embodiment of the present invention and comprising a locking element which selectively lockingly engages the wire; and Fig. 4 is a simplified pictorial illustration of an electronic seal constructed and operative in accordance with still another preferred embodiment of the present invention and comprising a bobbin around which the wire is wound.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Reference is now made to Fig. 1 which illustrates an electronic seal 10 constructed and operative in accordance with a preferred embodiment of the present invention.

Electronic seal 10 preferably includes a housing 12 including alarm circuitry 14, which when actuated provides an alarm signal. Alarm circuitry 14 is preferably constructed in accordance with the circuitry disclosed in U.STPatent No. 6 ,002 ,343 A wire extends from housing 12 and is in electrical communication with alarm circuitry 14. Wire 16 is attached at a first point 18 and at a second point 20 thereof to housing 12. In the illustrated embodiment, first and.second points 18 and 20 are electrical connectors mounted on an external surface of housingT2. For convenience, a jack 19 may be attached to one end of wire 16 which fixedly mates with on of these electrical connectors. A tying portion 22 of wire 16 is defined between first and second points 18 and 20 which is suitable for tying an object, such as a sack or hasp, for example. Tampering with any portion of wire 16 actuates alarm circuitry 14. For example, as taught in U.S. Patent . No . 6 , 002 ,343 .wire 16 may be a frangible element, such as a shielded wire, which when broken provides an output indication of tampering with seal 10. Alternatively, wire 16 may comprise electrically resistive wire, and tampering with wire 16 causes a change in electrical resistance of the wire, which change is communicated to alarm circuitry 14 for actuation thereof.

In order not to have an unwanted dangling portion of wire 16 after tying the object, an adjustment device 24 is provided for adjusting a length of tying portion 22. In the embodiment of Fig. 1, adjustment device 24 comprises a yoke 26 for wrapping therearound tying portion 22. Typically a user ties an object with wire 16, jack 19 being the free end of wire 16 during tying, and wraps any extra wire around yoke 26. Thereafter, jack 19 is fixedly connected to housing 12 at first point 18, and seal 10 is ready for monitoring any tampering with the object. An electrical element 28, such as an electrically resistive element or a conductive wire, is disposed through yoke 26, electrical element 28 being in electrical communication with alarm circuitry 14. Tampering with yoke 26, or with the windings of wire 16 therearound, causes a change in electrical resistance, capacitance or any other electrical parameter, of electrical element 28, which change is communicated to alarm circuitry 14 for actuation thereof.

Reference is now made to Fig. 2 which illustrates an alternative version of seal 10 wherein yoke 26 is replaced by an extender yoke 29. In this embodiment, first and second points 18 and 20 are electrical connectors mounted on an external surface of extender yoke 29. In this embodiment, electrical element 28 is routed through the entire inner structure of extender yoke 29. Except for the aforementioned differences, the embodiment of Fig. 2 operates identically to the embodiment of Fig. 1.

Reference is now made to Fig. 3 which illustrates an electronic seal 30 constructed and operative in accordance with yet another preferred embodiment of the present invention. Electronic seal 30 is preferably similar in construction to seal 10, with like elements being designated by like numerals. Electronic seal 30 differs from seal 10 in that seal 30 includes an adjustment device 32 which comprises a tightening device 34 to which wire 16 is attached. Tightening device 34 preferably includes a conduit 36 through which wire 16 can be drawn out of and pulled into housing 12 (in the directions generally indicated by arrows 38), and a locking element 40 which selectively lockingly engages wire 16 so as to substantially fix wire 16 at a second point 42 thereof. Locking element 40 may be in electrical communication with alarm circuitry 14 and may comprise a solenoid which clamps down on wire 16, for example. In this embodiment, wire 16 is preferably an unshielded resistive wire whose resistance can be measured from the outside, such as a conductive elastomer, e.g., an elastomeric RF gasket material. The skilled artisan will appreciate that other types of locking elements may be readily employed as well. In Fig. 3, it is seen that alarm circuitry 14 may include an antenna 44 for wirelessly communicating the alarm signal.

In accordance with a preferred embodiment of the present invention, a portion of wire 16 can be used to form part of a Wheatstone bridge 37, in electrical communication with alarm circuitry 14, for measuring changes in electrical resistance of wire 16.

Reference is now made to Fig. 4 which illustrates an electronic seal 50 constructed and operative in accordance with yet another preferred embodiment of the present invention. Electronic seal 50 is preferably similar in construction to seal 10, with like elements being designated by like numerals. Electronic seal 50 differs from seal 10 in that seal 50 includes an adjustment device 52 which comprises a tightening device 54 to which wire 16 is attached. Tightening device 54 preferably includes a bobbin 56 around which wire 16 is wound and a locking element 58 which selectively lockingly engages bobbin 56. Bobbin 56 may include a gear, in which case locking element 58 may include a tongue which engages the teeth of the gear so as to substantially fix wire 16 at a second point 59 thereof. Locking element 58 may be in electrical communication with alarm circuitry 14 and may comprise a solenoid, for example. The skilled artisan will appreciate that other types of locking elements may be readily employed as well. In addition, it is appreciated that locking element 58 may be manually or automatically locked and unlocked, as well as by remote control. Preferably the angular position and/or rotation of bobbin 56 is measured by a measuring device 60, such as an encoder. The initial angular position of bobbin 56, i.e., after sealing the object with seal 50, is fed to the alarm circuitry 14. Any angular change in the position of bobbin 56 is then used as a criterion for detection of tampering.

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 features described hereinabove as well as modifications and variations thereof which would occur to a person of skill in the art upon reading the foregoing description and which are not in the prior art. 125644/3

Claims (15)

1. An electronic seal comprising:. a portable housing; alarm circuitry which when actuated provides an alarm signal; a wire extending from said housing and in electrical communication with said alarm circuitry, whereby tampering with said wire causes actuation of said alarm circuitry; a locking element which selectively lockingly engages said wire to said housing; and a wireless communication device for wirelessly communicating the alarm signal .

2. The electronic seal according to claim 1, wherein said alarm circuitry detects an open circuit in a circuit comprising said alarm circuitry and at least one of said wire and said locking element .

3. The electronic seal according to claim 1, wherein said locking element comprises a solenoid which selectively lockingly engages said wire.

4. The electronic seal according to claim 3, wherein said solenoid comprises a tongue which selectively protrudes from said solenoid and fixedly clamps said wire.

5. The electronic seal according to claim 3, wherein said wire is wound around a bobbin and said solenoid selectively fixedly clamps said bobbin, thereby also claraping said wire.

6. The electronic seal according to claim 1, wherein said wire which extends from said housing is attached at a first point and at a second point thereof to said housing, and a portion of 125644/3 said wire between said first and second points, called a tying portion, is suitable for tying an object, wherein tampering with said wire actuates said alarm circuitry, and the seal further comprises an adjustment device for adjusting a length of said tying portion.

7. An electronic seal comprising: a housing comprising alarm circuitry, said alarm circuitry, when actuated providing an alarm signal; a wire extending from said housing and in electrical communication with said alarm circuitry, whereby tampering with said wire causes actuation of said alarm circuitry, said wire being attached at a first point and at a second point thereof to said housing, a portion of said wire between said first and second points, called a tying portion, being suitable for tying an object, wherein tampering with said wire actueites said alarm circuitry; a locking element which selectively lockingly engages said wire to said housing; a wireless communication device for wirelessly communicating the alarm signal; and an adjustment device for adjusting a length of said typing portion.

8. The electronic seal according to claim 7, wherein said adjustment device comprises a yoke for wrapping thersaround said tying portion.

9. The electronic seal according to claim 8, wherein an electrical element is disposed c rcugh said yoke, said electrical element being in electrical ormiu ioa ion with said alarm circuitry, wherein a change in an electrical parameter of said electrical element is communica ed zo said, alarm circuitry for actuation thereof . 125644/3

10. The electronic seal according to claim 7, wherein said adjustment device comprises a tightening device to which said wire is attached, said tightening device permitting said wire to be drawn out of and to be pulled into said housing, and substantially fixing said wire at said second point thereof.

11. The electronic seal according to claim 10, wherein said tightening device comprises a locking element which selectively lockingly engages said wire..

12. The electronic seal according to claim 10, wherein said tightening device comprises a bobbin around which said wire is wound and a locking element which selectively lockingly engages said bobbin.

13. The electronic seal according to claim 10, and further comprising a measuring device that measures a change in angular position of said bobbin, said measuring device using said change to actuate said alarm circuitry.

14. The electronic seal according to claim 7, wherein a portion of said wire forms part of a Wheatstone bridge in electrical communication with said alarm circuitry for measuring changes in electrical resistance of said wire.

15. The electronic seal according to claim 7, wherein said first point is attached to an electrical connector in electrical communication with said alarm circuitry. For the Applicant, Sanford T. Colb i Co. c : 31349 3