Measuring and testing – Vehicle chassis – Steering
Reexamination Certificate
2005-10-19
2008-08-12
McCall, Eric S (Department: 2855)
Measuring and testing
Vehicle chassis
Steering
Reexamination Certificate
active
07409854
ABSTRACT:
A method and apparatus for determining the operating condition of a turbine engine. An eddy current sensor is provided having a sensing field in communication with a plurality of rotating turbine blades during a revolution of a turbine engine. A threshold point value is defined for the signature data. A plurality of positive threshold point pairs and negative threshold point pairs are identified. A plurality of positive threshold widths from a plurality of times elapsed between the positive threshold point pairs and a plurality of negative threshold widths from a plurality of times elapsed between the negative threshold point pairs are determined. A plurality of threshold ratios are determined from a plurality of pairs of positive and negative threshold widths. A variance of the threshold ratios is correlated with an operating condition of the turbine engine.
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Kim Christine
Teolis Anthony
Teolis Carole
DLA Piper (US) LLP
McCall Eric S
Techno-Sciences, Inc.
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