GUARDING ALARM DEVICE Russian patent published in 1998 - IPC

FIELD: magnetic-contact continuous operation detectors. SUBSTANCE: device breaks circuit in case of mechanical interaction of intruder and guarded surface (such as room or shop windows, doors, walls and so on) and outputs alarm signal. In addition device outputs locking signal when external magnet or by-pass attempts using jumpers in electric circuit are detected. Device has permanent magnet unit and unit of magnetically controlled contacts (sealed reed contacts) which are mounted in separate housings. Housing contains two sealed reed contacts which are split by magnetic screen. Invention describes reed contact connection circuit and device design. EFFECT: continuous operations, increased reliability. 2 cl, 1 tbl, 3 dwg