| 摘要 |
PURPOSE:To make the digital display of an output easy, with a sensor miniaturized with precision by constituting a transducer with a piezoelectric oscillator and a resonance plate. CONSTITUTION:The external circumference of a transducer 8 is sealed and fixed at one opening of a case 9 and the air layer at the inside and outside of the case 9 is completely separated. A lead 10 is connected to one surface of a piezoelectric porcelain oscillator 6 of the transducer 8 and a lead 11 is connected to one surface of a resonance plate 7. An air permeable fixed plate 12 is provided at the other open end of the case 9 and the leads 10 and 11 are fixed. According to the change in pressure exerted on the measurement plane of the transducer 8, the impedance characteristics of the transducer 8 are fluctuated, the oscillation mode position of the transducer 8 is moved and the resonance frequency on the impedance characteristics is changed. As a result, an output in a stable dynamic range can be picked up. |
