| 摘要 |
PURPOSE:To provide a plate wave ultrasonic device in which the velocity of a plate wave varies in compliance with the viscosity of liquid. CONSTITUTION:When rf pulses are fed to a reed-screen-shaped electrode 2, SH wave is energized in the direction of another reed-screen-shaped electrode 3. The SH wave is transmitted in a piezo ceramic 1 where a liquid is loaded on a metal thin film 4. Because the transmitted speed of the SH wave is related to the viscosity of liquid, the viscosity of a specimen to be measured can be calculated from the speed difference in the loaded state between the reference specimen and the specimen to be measured. Thereby a viscosity sensor can be achieved which presents measurability for specimen even through it is in a minute quantity, ensures simple handling and shortened measuring time, allows being constructed light and small, eliminates electric and mechanical affections on the specimen, and presents good sensitivity to permit sensing even fine change of viscosity. |
