Patent ID: 6151956
Filing Date: 2000-11-28
Classification: G01N

Abstract:
An oil deterioration sensor which can distinguish deterioration characteristics or a liquid surface of oil by utilizing ultrasonic waves, characterized in that a deterioration sensor reflecting surface for reflecting ultrasonic waves transmitted from an ultrasonic wave transmitting portion is placed in oil so as to detect deterioration of the oil, and comprising: an oil deterioration detecting portion for detecting a transmission velocity of an ultrasonic wave in the oil by receiving ultrasonic waves from said deterioration sensor reflecting surface and for determining a base number of the oil as a measure of a degree of deterioration of oil from said transmission velocity of the oil; and an oil level detecting portion for transmitting ultrasonic waves from said ultrasonic wave transmitting portion to an air-liquid liquid surface of the oil and for detecting a height of said liquid surface by receiving ultrasonic waves from said liquid surface.