Claims
- 1. Apparatus for measuring the distance between a blade in a rotating row of blades and a reference position comprising:
- (A) sensor means located at said reference position and operable to provide an output signal indicative of blade proximity;
- (B) said output signal including positive and negative peak portions as a result of the passage of said blade past said sensor;
- (C) means responsive to said output signal for obtaining an indication of the positive to negative peak-to-peak value of said output signal;
- (D) means responsive to said indication for obtaining a signal indicative of said peak-to-peak value; and
- (E) means responsive to said signal indicative of said peak-to-peak value for providing an indication of said distance.
- 2. Apparatus according to claim 1 wherein:
- (A) said output signal includes cyclical positive and negative peak portions as a result of the passage of said blades of said row, past said sensor means; and which includes
- (B) means for obtaining an average value of two successive peaks of the same polarity and subtracting therefrom the value of the intervening peak of opposite polarity, to obtain a peak-to-peak value.
- 3. Apparatus according to claim 1 wherein:
- (A) said blade row is subject to movement perpendicular to the general plane of said blade row; and which includes
- (B) means for modifying said peak-to-peak value as a function of any said movement.
- 4. Apparatus according to claim 1 which includes:
- (A) a plurality of said sensors disposed about said blade row.
- 5. Apparatus according to claim 4 wherein:
- (A) said blades are steam turbine blades surrounded by a steam flow guide; and
- (B) said sensors being disposed within said flow guide.
Parent Case Info
This is a division of application Ser. No. 413,638, filed Aug. 31, 1982, now U.S. Pat. No. 4,518,917.
US Referenced Citations (14)
Foreign Referenced Citations (2)
Number |
Date |
Country |
515912 |
Aug 1955 |
CAX |
204463 |
Dec 1982 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
413638 |
Aug 1982 |
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