Radio frequency identification (RFID) security tag for merchandise and method therefor

• US 6,043,746 A
• Filed: 02/17/1999
• Issued: 03/28/2000
• Est. Priority Date: 02/17/1999
• Status: Expired due to Term

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Microchip Technology Incorporated
• Inventors: Sorrells, Peter
• Primary Examiner(s): Lee, Benjamin C.
• Application Number:
  US09/251,374
• Time in Patent Office: 405 Days
• Field of Search: 340/572.7, 340/572.8, 340/572.1, 340/573.3, 340/573.4, 340/573.1, 343/718, 343/878, 343/867, 343/873, 455/100
• US Class Current: 340/572.7
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card

Abstract

A Radio Frequency Identification (RFID) security tag for attachment to a small article of merchandise to monitor the tagged item. The security tag uses a thin flexible strip. An RFID tag device is coupled to the thin flexible strip and is used for storing data related to the small article of merchandise to be monitored. A plurality of conductors are laid on the thin flexible strip. The plurality of conductors are coupled together to form a multiple turn coil for providing energy to the RFID tag device when a first end of the thin flexible strip is coupled to a second end of the thin flexible strip to form a loop.

Claims

1. A security tag for attachment to a small article of merchandise comprising, in combination:

a thin flexible strip;

a Radio Frequency Identification (RFID) tag device coupled to said thin flexible strip for storing data related to said small article of merchandise; and

a plurality of conductors laid on said thin flexible strip wherein said plurality of conductors are coupled together to form a multiple turn coil for providing energy to said RFID tag device when a first end of said thin flexible strip is coupled to a second end of said thin flexible strip to form a loop.

2. A security tag for attachment to a small article of merchandise in accordance with claim 1 wherein each of said plurality of conductors are laid parallel to one another on said thin flexible strip.

3. A security tag for attachment to a small article of merchandise in accordance with claim 2 wherein a first of said plurality of conductors and a last of said plurality of conductors are coupled to said RFID tag device.

4. A security tag for attachment to a small article of merchandise in accordance with claim 2 wherein at least three of said plurality of conductors are coupled to said RFID tag device.

5. A security tag for attachment to a small article of merchandise in accordance with claim 3 wherein each of said plurality of conductors is coupled to a directly succeeding conductor and said last conductor is directly coupled to said first conductor to form a single continuous conductor.

6. A security tag for attachment to a small article of merchandise in accordance with claim 5 wherein said single continuous conductor forms a multiple turn coil when said first end of said thin flexible strip is coupled to said second end of said thin flexible strip to form a loop.

7. A security tag for attachment to a small article of merchandise in accordance with claim 6 wherein said single continuous conductor forms a make/break connection with said RFID tag device to energize said RFID tag device.

8. A security tag for attachment to a small article of merchandise in accordance with claim 5 wherein each of said plurality of conductors has at least one connector for coupling each of said plurality of conductors to a directly succeeding conductor and for coupling said last conductor to said first conductor.

9. A security tag for attachment to a small article of merchandise in accordance with claim 8 wherein one of said connectors is a conductive adhesive for coupling said first end of said thin flexible strip to said second end of said thin flexible strip to form said loop.

10. A method of providing a security tag for attachment to a small article of merchandise comprising the steps of:

providing a thin flexible strip;

providing a Radio Frequency Identification (RFID) tag device coupled to said thin flexible strip for storing data related to said small article of merchandise; and

providing a plurality of conductors laid on said thin flexible strip wherein said plurality of conductors are coupled together to form a multiple turn coil for providing energy to said RFID tag device when a first end of said thin flexible strip is coupled to a second end of said thin flexible strip to form a loop.

11. The method of claim 10 wherein said step of providing a plurality of conductors further comprises the step of laying each of said plurality of conductors parallel to one another on said thin flexible strip.

12. The method of claim 11 further comprising the step of coupling a first of said plurality of conductors and a last of said plurality of conductors to said RFID tag device.

13. The method of claim 11 further comprising the step of coupling at least three of said plurality of conductors to said RFID tag device.

14. The method of claim 12 further comprising the steps of:

coupling each of said plurality of conductors to a directly succeeding conductor; and

coupling said last conductor directly to said first conductor to form a single continuous conductor.

15. The method of claim 14 wherein said single continuous conductor forms a multiple turn coil when said first end of said thin flexible strip is coupled to said second end of said thin flexible strip to form a loop.

16. The method of claim 15 wherein said single continuous conductor forms a make/break connection with said RFID tag device to energize said RFID tag device.

17. The method of claim 14 further comprising the step of providing at least one connector for each of said plurality of conductors for coupling each of said plurality of conductors to a directly succeeding conductor and for coupling said last conductor to said first conductor.

18. The method of claim 17 wherein said step of providing at least one connector for each of said plurality of conductors further comprises the step of providing a conductive adhesive as at least one of said connectors for each of said plurality of conductors for coupling said first end of said thin flexible strip to said second end of said thin flexible strip to form said loop.