ELECTRONIC ARTICLE SURVEILLANCE TAG WITH TAMPER RESISTANT MAGNETIC LOCK

摘要

Method for operating a magnetically controlled lock in an EAS tag (100) involves the application of a magnetic field to a plunger (322) within a housing (102) of the EAS tag. The applied magnetic field is used to cause a translational movement of the plunger in a first direction. The method can further involve causing a latch (320) to pivot about a pivot axis (807) by using the translational motion (1002) of the plunger to apply a torque (1004) to the latch. Rotation of the latch in this way causes it to move to an unlocked position which releases a locking pin (106).

主权项

1. A magnetic lock that is resistant to defeat caused by forceful impacts, comprising
a housing formed of a rigid material; a pin channel defined within the housing, the pin channel arranged to removably receive therein a locking pin along a channel axis; a latch assembly disposed within the housing, the latch assembly including
a latch disposed adjacent to the pin channel, the latch pivotally mounted within the housing, the latch configured to lockingly engage the locking pin when in a first pivot position, and to release the locking pin in a second pivot position,a plunger formed of material responsive to an applied magnetic field, the plunger including an engagement face;a plunger guide channel formed in the housing, the plunger guide channel arranged to facilitate translational movement of the plunger along a guide channel axis from a first position to a second position when the plunger is exposed to the applied magnetic field;a resilient member arranged to resiliently urge the engagement face of the plunger into contact with a base of the latch; wherein the latch is responsive to the translational movement of the plunger from the first position to the second position to cause the latch to move from the first pivot position to the second pivot position.