APPARATUS FOR DETECTING LEAKAGE OF LIQUID IN TANK

摘要

An apparatus for detecting leakage of a liquid in a tank, where erroneous detection is suppressed and which is capable of fine and accurate display and warning that depend on the degree of increase and decrease in the quantity of the liquid. The apparatus performs a first liquid quantity variation detection for detecting liquid quantity variation based on a flow rate corresponding value that is calculated using an output of a flow rate sensor section and also performs a second liquid quantity variation detection for detecting liquid quantity variation based on a time variation rate of a liquid level that is measured by the pressure sensor. When it is determined in a first stage (S1) that an absolute value of the liquid quantity variation obtained by the second liquid quantity variation detection does not exceed a first predetermined value (C1), then, in a second stage (S2) after an intermediate stage (Si), an average absolute value of liquid quantity variation is obtained from liquid quantity variations that are obtained by the second liquid quantity variation detection of plural times. After that, when it is determined that the average absolute value exceeds a second predetermined value (C2) that is smaller than the first predetermined value, an average value of liquid quantity variation relating to the average absolute value of liquid quantity variation is outputted as a liquid quantity variation, and when it is determined that the average absolute value does not exceed the second predetermined value (C2), the liquid quantity variation obtained by the first liquid quantity variation detection is outputted.