| 摘要 |
PURPOSE:To enable highly versatile and easy liquid detection by detecting a capacity current or an oxidation-reduction current occurring between two electric conductors as pair when the pair are in contact with liquid, thereby detecting pressure of the liquid. CONSTITUTION:A liquid detection system 1 comprises a liquid reservoir vessel 2 for detecting the presence of liquid, a pair of electric conductors 4,4 inserted in the vessel 2, an external DC supply 5 for supplying a specific DC voltage between the electric conductors 4,4 and an amplifier 6 and a galvanometer 7 for measuring a current occurring between the electric conductors 4,4. When the electric conductors 4,4 get in contact with water by introducing it, charges(minus) therebetween migrate so as to maintain electrical neutrality in the interface between the liquid and the electric conductor by neutralizing the surface charge (plus) of the electric conductor, and the capacity current gradually attenuates in the process of forming an electric double layer. The capacity current, however, does not become zero due to such as a charge fluctuation on the side of liquid up to attainment of electrical neutrality, so that there flows a specific current. Accordingly, by detecting presence/absence of this steady capacity current, it is decided whether there is liquid, or not, within the vessel 2. |
