Patents Assigned to Commtest Instruments Limited
  • Patent number: 7805281
    Abstract: The present invention relates to vibration analysis and in particular, but not limited to, the derivation of multiple types of vibration signals from one vibration signal for vibration analysis. In the preferred method of the invention the vibrations of an object are measured using at least one vibration sensor, wherein the vibration sensor converts vibrations into an electrical vibration signal. The electrical vibration signal is digitized based on a first frequency, wherein the first frequency is selected from a plurality of possible frequency values. A first type of vibration signal is derived from the digitized vibration signal. A second type of vibration signal is then derived from the digitized vibration signal based on a second frequency. The second frequency is rationally determined from, and lower than, the value selected for the first frequency. The invention also provides apparatus for deriving multiple types of vibration signals from one measured vibration signal for vibration analysis.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: September 28, 2010
    Assignee: Commtest Instruments Limited
    Inventor: Nigel Leigh
  • Patent number: 7493220
    Abstract: The present invention relates to a vibration signal processing method and system that can be used to account for situations where impact or impulse events are hidden in a normal vibration reading by low frequency vibrations and high frequency noise. In one preferred form, the method of the present invention comprises the steps of obtaining electrical vibration signals that represent mechanical vibrations of a machine (102-106), converting the electrical vibration signals into digital vibration samples (108), dividing the digital vibration samples into equal time intervals and determining the average absolute amplitude of the digital vibration samples for each time interval (110), generating a time waveform comprising the determined average amplitudes (112, 114), and processing the time waveform as if it were an independently-detected signal (116-120).
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: February 17, 2009
    Assignee: Commtest Instruments Limited
    Inventors: Nigel Leigh, Carl Omundsen