Multiple-use deactivation device for electronic article surveillance markers
US6011474A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Apr 28, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2411
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A single deactivation device is used to deactivate both harmonic type EAS markers and magnetomechanical type EAS markers. The deactivation device includes a housing, and a permanent magnet and a coil disposed within the housing. The coil is circular and is arranged concentrically with, and outside of, the permanent magnet. The permanent magnet forms a DC magnetic field for deactivating the harmonic type marker by magnetizing control elements thereof. The coil is driven to generate an AC magnetic field that deactivates the magnetomechanical type marker by degaussing a control element thereof. The maximum amplitude of the AC magnetic field is lower than the level of the DC magnetic field, and is substantially below the coercivity of the control elements of the harmonic type marker. The coercivity of the control element of the magnetomechanical type marker is low enough to be degaussed by the AC magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.