Magnetomechanical tag used in electronic article surveillance and method of manufacturing a magnetomechanical tag

• US 7,623,039 B2
• Filed: 07/25/2006
• Issued: 11/24/2009
• Est. Priority Date: 07/25/2006
• Status: Active Grant

• Current Assignee: Sensormatic Electronics LLC (Johnson Controls International plc)
• Original Assignee: Sensormatic Electronics Corporation (Johnson Controls International plc)
• Inventors: Liu, Nen-Chin
• Primary Examiner(s): La; Anh V
• Application Number:
  US11/493,410
• Publication Number:
  US 20080030338A1
• Time in Patent Office: 1,218 Days
• Field of Search: 340/572.1, 340/572.8, 340/572.5, 340/572.6, 340/551, 340/572.7, 296/021, 29/253.5
• US Class Current: 340/572.6
• CPC Class Codes: G08B 13/2408 using ferromagnetic tags
• CPC Class Codes: G08B 13/2437 Tag layered structure, processes for making layered tags

Abstract

A magnetomechanical tag for use in an electronic article surveillance (EAS) system and a method of manufacturing the magnetomechanical tag may be provided. The EAS may include at least one resonator, a housing configured to allow vibration therein of the at least one resonator and a cover heat sealed to the housing at a heat sealing temperature. The EAS tag further may include a powder lubricant within the housing. The powder lubricant may have a melting temperature less the heat sealing temperature.

Claims

1. An electronic article surveillance (EAS) tag comprising:

at least one resonator;

a housing having a sealing portion, the housing being configured to allow vibration therein of the at least one resonator;

a cover heat sealed to the sealing portion of the housing at a heat sealing temperature; and

a powder lubricant within the housing, the powder lubricant applied to the sealing portion of the housing and to the at least one resonator, the powder lubricant having a melting temperature less than the heat sealing temperature.

2. An EAS tag in accordance with claim 1 wherein the sealing portion is a flange.

3. An EAS tag in accordance with claim 1 wherein the powder lubricant forms a heat sealed bond sealing the cover to the sealing portion.

4. An EAS tag in accordance with claim 1 wherein the sealing portion comprises a flange having a bonding layer formed from a material having a melting temperature greater than the melting temperature of the powder lubricant and less than or about equal to the heat sealing temperature.

5. An EAS tag in accordance with claim 1 wherein the cover further comprises a bonding layer formed from a material having a melting temperature greater than the melting temperature of the powder lubricant and less than or about equal to the heat sealing temperature.

6. An EAS tag in accordance with claim 1 wherein at least one of the sealing portion and cover comprises a bonding layer formed from a low density polyethylene (LDPE) material.

7. An EAS tag in accordance with claim 1 wherein the cover includes the powder lubricant on at least a portion of the cover.

8. An EAS tag in accordance with claim 1 wherein the powder lubricant comprises one of a low density polyethylene (LDPE) material, a medium density polyethylene (MDPE) material, a high density polyethylene (HDPE) and a polyethylene (PE) oxide material.

9. An EAS tag in accordance with claim 1 wherein the heat sealing temperature is substantially 110 degrees Celsius.

10. An EAS tag in accordance with claim 1 wherein the sealing portion is a flange and the powder lubricant is applied to the housing by a lubricant dispenser.

11. An EAS tag in accordance with claim 10 wherein the powder lubricant is applied evenly to the flange.

12. A method for sealing an electronic article surveillance (EAS) tag, the method comprising:

applying a powder lubricant to a sealing portion of the EAS tag and to at least one resonator to lubricate the at least one resonator, the powder lubricant having a melting temperature less than a heat sealing temperature; and

heat sealing the sealing portion by melting the powder lubricant.

13. A method in accordance with claim 12 further comprising applying a powder lubricant within a housing portion of the EAS tag.

14. A method in accordance with claim 12 wherein the sealing portion comprises a bonding layer and the heat sealing comprises applying heat at a temperature to melt the bonding layer, with the melting temperature of the powder lubricant less than the melting temperature of bonding layer.

15. A method in accordance with claim 12 wherein the heat sealing comprises applying heat at a temperature of substantially 110 degrees Celsius.

16. A method in accordance with claim 12 further comprising applying a powder lubricant to a cover portion of the EAS tag.

17. A method in accordance with claim 12 wherein the applying comprises dispensing the powder lubricant from a lubricant dispenser directly on the EAS tag.

18. A method for assembling an electronic article surveillance (EAS) tag, the method comprising:

positioning a lidstock cover over a coverstock housing such that an edge of the lidstock cover aligns with an edge of a flange of the coverstock housing;

applying a powder lubricant to the flange of the coverstock housing and to at least one resonator inside the coverstock housing, the powder lubricant having a melting temperature less than a heat sealing temperature; and

heating the flange of the coverstock housing wherein a bonding layer comprising the powder lubricant melts to seal the lidstock cover and the coverstock housing.

19. A method in accordance with claim 18 wherein the bonding layer comprises a heat sealing material, and wherein the powder lubricant has a melting temperature lower than the melting temperature of the heat sealing material.

20. A method in accordance with claim 18 wherein the powder lubricant comprises a low density polyethylene (LDPE) material.