Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Patent
1990-05-29
1992-11-24
Wieder, Kenneth A.
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
324683, G01R 2726
Patent
active
051666260
ABSTRACT:
A hot gas turbine engine capacitive probe clearanceometer is employed to measure the clearance gap or distance between blade tips on a rotor wheel and its confining casing under operating conditions. A braze sealed tip of the probe carries a capacitor electrode which is electrically connected to an electrical inductor within the probe which is inserted into a turbine casing to position its electrode at the inner surface of the casing. Electrical power is supplied through a voltage controlled variable frequency oscillator having a tuned circuit in which the probe is a component. The oscillator signal is modulated by a change in electrical capacitance between the probe electrode and a passing blade tip surface while an automatic feedback correction circuit corrects oscillator signal drift. A change in distance between a blade tip and the probe electrode is a change in capacitance therebetween which frequency modulates the oscillator signal. The modulated oscillator signal which is then processed through a phase detector and related circuitry to provide an electrical signal is proportional to the clearance gap.
REFERENCES:
patent: 2842738 (1958-07-01), Warnick
patent: 3805150 (1974-04-01), Abbe
patent: 3826980 (1974-07-01), Diechelmann et al.
patent: 4063167 (1977-12-01), Duly
patent: 4329644 (1982-05-01), Libertini et al.
patent: 4568873 (1986-02-01), Oyanagi et al.
patent: 4804905 (1989-02-01), Ding et al.
patent: 4806848 (1989-02-01), Demers
patent: 4813273 (1989-03-01), Parsons
patent: 4818948 (1989-04-01), Dooley
patent: 4823071 (1989-04-01), Ding et al.
Electronics, p. 147, May 1953.
Hester Norbert J.
Hornbeck Charles E.
Young Joseph C.
General Electric Company
Regan Maura K.
Shay Bernard E.
Squillaro Jerome C.
Wieder Kenneth A.
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