Oil deterioration detector.

摘要

An apparatus detects the degree of deterioration of lubricating oil used in an internal combustion engine by measuring the dielectic constant of the lubricating oil. The apparatus includes a sensor (16) having a pair of spaced apart electrodes dipped under the lubricating oil to form a sensor capacitor whose capacity varies as a function of the dielectric constant of the lubricating oil. The sensor capacitor is connected to a fixed capacitor to form a voltage divider connected across an AC voltage source (14) which generates an AC voltage of a constant frequency so that a voltage is developed across the sensor capacitor which voltage corresponds to the dielectric constant of the lubricating oil. The frequency of the AC voltage is set at a value ranging from 50 KHz to 500 KHz.