Antipilferage tags having an acoustic resonator chamber
US4999609A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 27, 1989 |
| Grant date | Mar 12, 1991 |
| Priority date | — |
| Expiry date | Apr 27, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2434
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An antipilferage tag (10) includes an acoustic resonator chamber (12) which has a membrane (1,2) formed of a layer of magnetostrictive material (2) as well as a system which may incorporate such tags. The system has a generator for generating an alternating magnetic field and a tag capable of interacting with the alternating magnetic field to generate an alarm tone, characterized in that (i) the alarm tone is generated by a tag which includes an acoustic resonator; and (ii) the generator for generating an alternating magnetic field and the tag are so arranged that an audible alarm tone is generated by the tag when it is subjected to the alternating magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.