Magnetic security tag assembly

• US 7,750,806 B1
• Filed: 08/08/2007
• Issued: 07/06/2010
• Est. Priority Date: 08/08/2007
• Status: Expired due to Fees

• Current Assignee: Johan Skjellerup, Pu Chen
• Original Assignee: Johan Skjellerup, Pu Chen
• Inventors: Chen, Pu, Skjellerup, Johan
• Primary Examiner(s): Nguyen; Tai T
• Application Number:
  US11/891,039
• Time in Patent Office: 1,063 Days
• Field of Search: 340/568.1, 340/551, 340/572.1, 340/572.3, 340/572.9, 340/825.54, 340/5.6, 70/571, 703/91, 704/16
• US Class Current: 340/568.1
• CPC Class Codes: E05B 73/0017 Anti-theft devices, e.g. tags or monitors, fixed to articles, e.g. clothes, and to be removed at the check-out of shops
• CPC Class Codes: G08B 13/2408 using ferromagnetic tags
• CPC Class Codes: G08B 13/2434 Tag housing and attachment details
• CPC Class Codes: G09F 3/0305 characterised by the type of seal used
• CPC Class Codes: G09F 3/0323 having clamp-like sealing means
• CPC Class Codes: Y10T 70/5004 For antitheft signaling device on protected article
• CPC Class Codes: Y10T 70/778 Operating elements
• CPC Class Codes: Y10T 70/7915 Tampering prevention or attack defeating

Abstract

A security tag assembly structured to discourage unauthorized removal of merchandise comprising a base including at least one magnetomechanical member normally operatively oriented in an armed mode. The armed mode is at least partially defined by the magnetomechanical member demonstrating a vibration or mechanical resonance when exposed to a predetermined resonant frequency, such as when passing through or otherwise disposed in proximity to a monitoring alarm assembly. A stabilizing assembly comprising at least one stabilizing magnet is disposed and structured to expose said magnetomechanical member to a stabilizing magnet field sufficient operative characteristics to facilitate restoration or maintenance of the armed mode of the magnetomechanical member even when exposed to a disruptive magnetic field, such as when the magnetomechanical member is attempting to be disarmed by an unauthorized source.

Claims

1. A security tag assembly structured to discourage unauthorized removal of merchandise from a given area, said security tag assembly comprising:

a base structured to be removably connected to the merchandise,

an alarm activating assembly comprising at least one magnetomechanical member operatively oriented in an armed mode,

said armed mode defined by a mechanical resonance of said one magnetomechanical member when exposed to a predetermined resonant frequency,

a stabilizing assembly comprising at least one stabilizing magnet disposed on said base in spaced relation to said alarm activating, and

said one stabilizing magnet disposed and structured to expose said one magnetomechanical member to a magnetic field of sufficient strength to restore or maintain said one magnetomechanical member in said armed mode upon exposure of said one magnetomechanical member to a disruptive magnetic field.

2. A security tag assembly as recited in claim 1 wherein said disruptive magnetic field is generated at a frequency other than said predetermined resonant frequency.

3. A security tag assembly as recited in claim 1 wherein said at least one stabilizing magnet, is disposed and structured to substantially continuously influence said magnetomechanical member into said armed mode.

4. A security tag assembly as recited in claim 3 further comprising a shielding assembly associated with said stabilizing assembly and structured to restrict a derogatory influence of a disruptive magnetic field on said one stabilizing magnet.

5. A security tag assembly as recited in claim 4 wherein said disruptive magnetic field is generated at a frequency other than said resonant frequency.

6. A security tag assembly as recited in claim 1 further comprising an attachment member removably connected to said base and a connector member disposed and structured to removably interconnect said base and said attachment member to the merchandise in an operative position.

7. A security tag assembly as recited in claim 6 further comprising a locking assembly disposed on said attachment member in locking engagement with said connector when said base and said attachment member are in said operative position.

8. A security tag assembly structured to discourage unauthorized removal of merchandise from a given area, said security tag assembly comprising:

a base structured to be connected to the merchandise,

an alarm activating assembly comprising at least two magnetomechanical members operatively oriented into an armed mode,

said armed mode defined by a mechanical resonance of said two magnetomechanical members when exposed to a magnetic field at a natural resonant frequency of said magnetomechanical members,

a stabilizing assembly including at least one stabilizing magnet connected to said base within a spaced, influencing range of said two magnetomechanical members of said alarm activating assembly, and

said one stabilizing magnet disposed and structured to expose said magnetomechanical members to a magnetic field having sufficient operative characteristics to facilitate maintenance of said two magnetomechanical members in said armed mode when exposed to a disruptive magnetic field.

9. A security tag assembly as recited in claim 8 further comprising said two magnetomechanical members each defined by an elongated flexible ribbon formed of a magnetorestrictive, ferromagnetic material.

10. A security tag assembly as recited in claim 9 wherein said magnetorestrictive ferromagnetic material comprises an amorphous metal.

11. A security tag assembly as recited in claim 8 wherein said disruptive magnetic field is generated at a frequency other than said predetermined resonant frequency.

12. A security tag assembly as recited in claim 8 further comprising a protective structure associated with said stabilizing assembly, said protective structure disposed and structured to restrict a derogatory influence of a disruptive magnetic field on said one stabilizing magnet.