| 摘要 |
PURPOSE:To eliminate the effect of vibrations and inclination by a method wherein the buoyancy proportional to the density of liquid to be measured which is applied to a float is transduced into an electric signal which is taken out through the intermediary of a filter. CONSTITUTION:When the liquid to be measured is made to flow from an inlet pipe 5 toward a discharge pipe 6, it applies no acting force to the float 7 and flows freely, since openings 7c are formed throughout the entire periphery of the base part 7a of the float 7. When a float chamber 4 is filled up with the liquid, the float 7 is given the buoyancy corresponding to the density of the liquid and a piezoelectric transducing element 8 located at the tip of a rod part 7b transduces this buoyancy into a voltage signal and delivers the same. From this output signal a high frequency is removed by the filter 9 and the constituent of a density signal alone is taken out to be compared with a reference value by a comparator 10 and then to drive a solenoid valve and the like for performing a control of the density. By this constitution, the effect of vibrations and the pulsation of the liquid is eliminated and the effect of the inclination of a sensor part 1 is also eliminated nearly at all. |
