LIQUID LEVEL DETECTION METHOD, LIQUID LEVEL DETECTION DEVICE, AND MACHINE TOOL PROVIDED WITH SAID LIQUID LEVEL DETECTION DEVICE

摘要

Provided is a liquid level detection device such that calibration is not necessary each time a measurement is performed, even if the type of liquid to be measured, or the mixture state with foreign matter, changes. A liquid level detection device is provided with: a level sensor (11) comprising a plurality of detection sensors arranged in a line, said detection sensors being capacitance-type detection sensors each having a pair of electrodes, wherein the output value of the detection sensors changes in accordance with the permittivity of the substance present around the electrodes; a parameter storage unit (17) in which is stored a correlation parameter that defines a correlation between output values respectively outputted from the detection sensors when the level sensor (11) is immersed in a liquid (C) and the actual level of the liquid relative to the level sensor (11); and a liquid-level estimation unit (16) that receives the output from each detection sensor in the level sensor (11) and estimates the level of the liquid (C) relative to the level sensor (11) on the basis of the output values received from each detection sensor and the correlation parameter stored in the parameter storage unit (17).