| 摘要 |
PURPOSE:To measure the specific gravity of liquid irrespectively of oscillations or the movement of the liquid by providing an ultrasonic oscillator and a receiver immersed into liquid to be measured by leaving a constant spacing between each and measuring the position difference of ultrasonic waves between the receiver and the oscillator. CONSTITUTION:A transmission element 3 and a reception element 4 are covered respectively with thin films 9, 10 of polyethylene and are mounted to the inside surface of a casing 8 made of a resin. The leads 11 of the element 3 are connected to an oscillator 5 and the leads 12 of the element 4 to an amplifier 6. The relations between the specific gravity of electrolyte and output voltage at the case in which the oscillation frequency of the oscillator 5 is defined as 50kHz and the distance between the elements 3, 4 as 2cm are as shown in the figure, wherein the output when specific gravity is changed changes roughly linearly. The hydrometer by this invention does not receive the influence of the oscillation during measurement and the movement of the liquid and is suited for conversion to electric signals. |
