| 摘要 |
PURPOSE:To make it possible to detect easily a discontinuity of a piezoelectric element by a method wherein a resistance value between signal lead-out parts provided on both ends of each of electrode materials, which are respectively affixed on both surfaces of a piezoelectric material, is detected. CONSTITUTION:A piezoelectric element is constituted of a high-molecular piezoelectric material 6, such as a PVDF material, electrode terminals 7 and 8, which are respectively affixed on both surfaces of the material 6, and signal lead-out parts 9 and 10 and 11 and 12, which are respectively provided on both ends of each of the materials 7 and 8. A discontinuity of the electrode 7 can be detected by detecting a resistance value between the lead-out terminal parts 9 and 10 and a discontinuity of the material 8 can be detected by detecting a resistance value between the lead-out terminal parts 11 and 12. In the case where the body movement characteristics of the human body are detected, a resistance value is led out from between the lead-out parts 9 and 11, for example, or between the lead-out parts 10 and 12. Thereby, in the case where the piezoelectric element provided at a seat, for example, is cut and torn by a sharp edged tool or the like by mistake, a discontinuity of the element can be easily detected. |
