Arrangement of piezoelectric elements in passive glass breakage detectors

摘要

In the arrangement of piezoelectric elements in passive glass breakage detectors, the invention proposes that in each case at least two piezoelectric elements are attached arranged at a specific angle relative to one another in accordance with their privileged direction and with reference to their sensitivity to mechanical vibrations. This angle is chosen such that upon the occurrence of vibrations characteristic of glass breakage at least one of the piezoelectric elements emits an output power sufficient to raise an alarm independently of the direction of said vibrations. The interconnection of the piezoelectric elements arranged in such a way means that the output powers add together, so that even in the event of an unfavourable occurrence of mechanical vibrations at the glass breakage detector a reliable raising of the alarm is ensured.