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US 8,978,427 B2Granted
Tamper resistant security tag
AssigneeTyco Fire & Security GmbH
InventorsWing Kei Ho, Gopal Chandramowle
Life of this patent
Estimating the term…
Abstract
Security tag includes a housing and a movable locking element. A latch within the housing is resiliently biased toward the movable locking element and movable responsive to a magnetic field between a locked position and an unlocked position. A guide structure is arranged to constrain movement of the latch. The latch and the guide structure are cooperatively arranged to ensure an engagement that will disrupt a motion trajectory of the latch occurring when the housing is subjected to a physical impact. Consequently, the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to the physical impact.
Claims20
A tamper-resistant security tag comprising:
- a housing;
- a locking element movably disposed within the housing;
- a latch disposed within the housing and movable responsive to application of a magnetic field between a locked position, in which movement of the locking element is prevented by the latch, and an unlocked position, in which movement of the locking element is unrestricted by the latch;
- a resilient member arranged to resiliently bias the latch in a direction toward the locked position;
- a guide structure within the housing arranged to constrain a movement of said latch;
- a first disrupter structure formed on the latch;
- a second disrupter structure formed on a portion of the guide structure at a location in which the first and second disruptor structures are at least partially aligned with each other when the latch is in the locked position;
- wherein said first and second disrupter structures each have a respective shape and position which in combination are configured to disrupt a motion trajectory of the latch as it moves from the locked position toward the unlocked position in response to the housing being subjected to a physical impact, whereby the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to the physical impact, and to selectively facilitate at least a portion of an unlocking movement of the latch in which said latch transitions fully from the locked position to the unlocked position in response to an applied magnetic field.
5 more elements
A tamper-resistant security tag comprising:
- a housing;
- a locking element movably disposed within the housing;
- a latch disposed within the housing and movable responsive to application of a magnetic field between a locked position, in which movement of the locking element is prevented by the latch, and an unlocked position, in which movement of the locking element is unrestricted by the latch;
- a resilient member arranged to resiliently bias the latch in a direction toward the locked position;
- a guide structure within the housing arranged to constrain a movement of said latch;
- a first disrupter structure formed on the latch;
- a second disrupter structure formed on a portion of the guide structure and arranged to engage said first disrupter structure;
- wherein said first and second disrupter structure each have a respective shape and position which in combination are configured to disrupt a motion trajectory of the latch as it moves from the locked position toward the unlocked position in response to the housing being subjected to a physical impact, whereby the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to the physical impact, and to selectively facilitate at least a portion of an unlocking movement of the latch in which said latch transitions fully from the locked position to the unlocked position in response to an applied magnetic field
- wherein the guide structure includes one or more lateral restraints arranged to facilitate translational movement of the latch within a latch channel along a path from the locked position to the unlocked position by constraining movement of the latch in a lateral direction transverse to the path;
- wherein the second disrupter structure is a stop, said stop positioned and arranged to limit the translational movement of the latch in a direction of travel toward the unlocked position by engaging the first disrupter structure of the latch as said latch moves toward the unlocked position;
- and
- wherein the stop is positioned at an end of the latch channel opposed from the locking element, and wherein first disrupter structure is shaped to pivot on the second disrupter structure to facilitate rotation of the latch about a latch pivot axis when the stop has engaged the portion of the latch and the latch is subjected to the magnetic field.
9 more elements
A tamper-resistant security tag comprising:
- a housing;
- a locking element movably disposed within the housing;
- a latch disposed within the housing and movable responsive to application of a magnetic field between a locked position, in which movement of the locking element is prevented by the latch, and an unlocked position, in which movement of the locking element is unrestricted by the latch;
- a resilient member arranged to resiliently bias the latch in a direction toward the locked position;
- a guide structure within the housing which constrains a movement of said latch includes
- one or more lateral restraints which facilitate translational movement of the latch within a latch channel along a path from the locked position to the unlocked position by constraining movement of the latch in a lateral direction transverse to the path, and
- a stop positioned at an end of the latch channel opposed from the locking element, the stop disposed to limit the translational movement of the latch in a direction of travel toward the unlocked position by engaging a portion of the latch;
- wherein the stop and at least one of the lateral restraints is arranged to facilitate rotation of the latch about a latch pivot axis when the stop has engaged the portion of the latch and the latch is subjected to the magnetic field, said engaging disrupting a motion trajectory of the latch occurring when the housing is subjected to a physical impact, whereby the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to the physical impact.
5 more elements
A tamper-resistant security tag comprising:
- a housing;
- a movable locking element disposed within the housing;
- a latch disposed within the housing and resiliently biased toward the movable locking element, the latch movable responsive to application of a magnetic field between a locked position, in which movement of the locking element is prevented by the latch, and an unlocked position, in which movement of the locking element is unrestricted by the latch;
- a guide structure within the housing arranged to constrain a movement of said latch;
- a first disrupter structure comprised of a concave surface formed on the latch;
- a second disrupter structure comprised of a protrusion formed on a portion of the guide structure at a location in which the first and second disruptor structures are at least partially aligned with each other when the latch is in the locked position, where the second disrupter structure positioned to engage the concave surface of the first disrupter structure as said latch approaches the unlocked position;
- wherein the concave surface and the protrusion are sized and shaped to disrupt a motion trajectory of the latch occurring when the housing is subjected to a physical impact, whereby the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to the physical impact, and to facilitate an unlocking movement of the latch in which said latch transitions fully from the locked position to the unlocked position in response to an applied magnetic field.
4 more elements
A method for preventing defeat of a security tag, comprising:
- disposing within a housing of the security tag a latch which is resiliently biased toward a movable locking element, and movable responsive to application of a magnetic field between a locked position, in which movement of the locking element is prevented by the latch, and an unlocked position, in which movement of the locking element is unrestricted by the latch;
- providing a guide structure within the housing to constrain a movement of said latch along a translational path defined by the guide structure, where the guide structure has a first disruptor structure formed thereon at a location in which the first disruptor structure is at least partially aligned with a second disruptor structure formed on the latch;
- disrupting with the first and second disruptor structures a motion trajectory of the latch as it travels along the translational path in response to a physical impact upon the housing so that the latch is selectively inhibited from moving fully from the locked position to the unlocked position when the housing is subjected to a physical impact;
- and
- guiding an unlocking movement of the latch with the guide structure in which said latch transitions fully from the locked position to the unlocked position in response to an applied magnetic field.
2 more elements
Dependencies are inferred from the claim text.