Anti-theft alarm device for e.g. tarpaulin, on truck, has electronic alarm device connected to and controlled by pressure sensors, where device is triggered by detection of variation of pressure converted and transmitted by sensors

摘要

The device has a sealing enclosure, which is in the form of double wall (2) and pressurized with gas e.g. air, with pressure higher than atmospheric pressure. The enclosure is integrated to a tarpaulin (1) and covers a surface of the tarpaulin. Pressure sensors (3) are connected to the enclosure to detect variation of sign pressure of security violation or an attempt of violation on the enclosure. Electronic alarm device is connected to and controlled by the sensors, where the device is triggered by the detection of variation of pressure converted and transmitted by the sensors.