Patents Assigned to Lubrigard Limited
  • Electrical measurement of oil quality
    Patent number: 6459995
    Abstract: Method and apparatus for measuring oil quality based on the permittivity of the oil comprising a capacitive or radiative sensor for exposure to the oil, and an oscillator circuit including the sensor, wherein the oscillator circuit comprises a LC or crystal oscillator which provides an output signal, the amplitude of which is dependent upon the lossiness of the Tan &dgr; of the oil, and a measuring device that responds to the amplitude of the output signal as a measure of oil quality.
    Type: Grant
    Filed: May 4, 2000
    Date of Patent: October 1, 2002
    Assignee: Lubrigard Limited
    Inventor: Christopher John Collister