Tamper detection mechanism
US6774807B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1999 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Mar 2, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B29/046
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
System and method for detecting an unauthorized movement of a communications or meter device, such as a meter that monitors and communicates a measure of use of energy or some other metered quantity (electrical, gas, water, etc.), to prevent meter tampering or removal. A bolt, screw, nail or other attachment mechanism, used to attach the device to a selected stationary or movable object, is provided with a permanent magnet having a selected magnetic field direction that can be transverse to, a selected attachment mechanism direction (e.g., transverse to a bolt shaft direction). A field-activated magnetic switch, such as a reed switch or a Hall effect switch, having a selected switch direction is located near the permanent magnet. If a user attempts to remove, or tamper with the position of, the communications device, by rotating or translating the attachment mechanism, the direction and/or magnitude of the magnetic field changes sufficiently to switch the switch from a first state (normal) to a second state (alarm), and an alarm signal is generated. In a second embodiment, a plunger connected to a micro switch is moved by a contact portion of an attachment mechanism as the attachme…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.