Capacitance liquid level detector

摘要

An electric liquid level detector for detecting the remaining quantity of liquid stored within a liquid container, comprising a pair of helically coiled electrodes extending vertically in the container and being fixed at their one ends to the upper portion of the container and at their other ends to the bottom of the container, the electrodes being submerged into the liquid stored within the container; and an oscillator circuit of the resistance capacity type including a variable condenser which consists of the electrodes, the oscillator circuit being arranged to oscillate at a frequency in dependence upon variation of the electrostatic capacitance between the electrodes so as to indicate the level of the stored liquid.