Scientific Generics Limited

Other

Meadwestvaco Corporation

Michael D Crossfield

Ross Jones

Peter Antony Farrar

Robert M Pettigrew

Stefan Alexander Pijanowski

Dafydd G Davies

Robert Johnston

Stephen H Chambers

Anthony H J Fraser

A security device for attachment to a container having external walls such that a transponder thereon is located externally of or adjacent to one of said external walls so as to avoid being shielded by a metal layer within the container (e.g. the metal layer within a disk such as a CD or DVD). The security device is arranged to trigger an alarm signal if the container is moved within the range of an alarm unit with the security device attached thereto, and has a releasable locking mechanism to secure it to the container such that release of the locking mechanism requires the use of authorized release means. In one embodiments the transponder is located in the vicinity of a window in a metal layer, e.g. at the centre of the disk.

Security device and transponder

An attachment device for a security or antipilferage tag, and a combination of such a device with the tag. The attachment device comprises a cap having an upper surface and a lower surface, and a pair of electrically conductive pins depending from the lower surface, and an electrical conductor within the body of said cap which makes an electrical connection between the pair of pins. The tag forming one element of the combined tag and attachment device includes a first opening adapted to receive one of the pins and to permit electrical contact between the one pin and a first part of the electrical circuit within the tag, and a second opening adapted to receive the other of the pair of pins and to permit electrical contact between the other pin and a further part of the electrical circuit within the tag. Unauthorised removal of the attachment device from the tag results in the generation of an alarm signal.

Security tag attachment

An antipilferage system for the detection of magnetic tags comprises an assembly (2) of spirally wound emitter (1) and/or detector (3a, 3b) coils. This arrangement enables a tag to be detected regardless of its orientation.

Antipilferage systems

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.

Antipilferage tags having an acoustic resonator chamber

A housing contains a pick-up coil for detecting an external magnetic field; a power supply; a tone generator; and an electric circuit powered by said power supply and arranged to activate said tone generator in response to an output from said magnetic field pick-up including a piezoelectric material surrounded about its circumference by a thin layer of magnetostrictive material. Since the electrical output of the piezoelectric material is dependent on the stress imparted to it by the magnetostrictive material, and since the dimensional change in the magnetostrictive material is proportional to the magnetic field in the environment in which the magnetostrictive material is located, the electrical output of the piezoelectric material provides a measure of magnetic field strength.

Growing community of inventors

Brackley, United Kingdom

Michael D Crossfield