摘要 |
<p>A method and apparatus for detecting the degree of deterioration of a lubricating oil for an operating machine includes a grid-like capacitive sensor (20) that uses the lubricating oil as a dielectric medium. A magnetic field is imposed upon the oil to attract ferromagnetic wear particles into the vicinity of the sensor. Preferably, the magnetic field is generated by at least two independently controlled electromagnet windings (26, 28) aligned such that the magnetic field produced by each winding acts upon the wear particles. A plurality of capacitance measurements are taken at periodic intervals at each of several magnet operational states for respective classification and analysis. All windings may be simultaneously de-energized for release of captured particles back in to an oil circulation stream and to clean the capacitative sensor grid of accumulated particulates.</p> |