| 摘要 |
PROBLEM TO BE SOLVED: To prevent breakage of a piezoelectric element due to an ambient environmental temperature change in a glass breakage sensor detecting an invader. SOLUTION: This glass breakage sensor is provided with a disk-shaped piezoelectric element 2 fixed inside a molded housing 1, which is attached to a glass pane G by a double-sided adhesive sheet, to convert vibration of the glass pane G into a voltage signal. The glass breakage sensor outputs an alarm if amplitude of an output signal from the piezoelectric element 2 is larger than an alarm threshold value. The piezoelectric element 2 is stuck to the housing 1 by means of an adhesive 3 with a Shore hardness A≤40. COPYRIGHT: (C)2004,JPO&NCIPI
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