Patent ID: 8664966
Filing Date: 2014-03-04
Classification: G01N

Abstract:
1. A method of evaluating a degree of degradation of a lubricating oil, comprising: using a device for evaluating a degree of degradation of a lubricating oil, the lubricating oil being free from a reference electrode, the device comprising a pH-ISFET and a first circuit for measuring a current flowing between a drain and a source of the pH-ISFET in a case where a constant voltage is applied between the drain and the source, or a second circuit for measuring a voltage between the drain and the source in a case where a constant current is caused to flow between the drain and the source; measuring the current flowing between the drain and the source of the pH-ISFET with the first circuit wherein the constant voltage is applied between the drain and the source, or measuring the voltage between the drain and the source with the second circuit wherein the constant current is caused to flow between the drain and the source by evaluating the degradation of the lubricating oil based on the measured current or based on the measured voltage.