Turbine blade vibration detection apparatus
First Claim
1. Blade vibration detection apparatus for detecting vibration of a blade in a rotating blade row of a machine, comprising:
- (A) a plurality of sensors disposed about said blade row with each sensor being operable to provide an output signal upon relative passage of a blade;
(B) signal conditioning means responsive to said sensor output signals and operable to provide respective corresponding sensor pulse signals;
(C) means for selecting a particular blade to be monitored;
(D) means for sequentially combining all of the sensor pulse signals caused by said selected blade as it passes the respective sensors, to derive a pulse train signal modulated as a function of any vibration of said selected blade; and
(E) detection circuitry including FM detection means operable to demodulate said pulse train signal to derive a blade vibration indicative signal.
2 Assignments
0 Petitions
Accused Products
Abstract
A plurality of sensors are disposed equally about a blade row in a turbine with each sensor being operable to provide an output signal in response to a passing blade. A blade is selected for monitoring purposes by designating its degree location relative to a reference position ± some angular distance constituting a small window. As the selected blade passes a sensor, its output signal, properly conditioned to form a pulse, is gated during the time period corresponding to the window. The sequential pulses of the sensors form a pulse train which is modulated by any blade vibration. An FM detector is provided for demodulating the pulse train to derive vibration information.
82 Citations
20 Claims
-
1. Blade vibration detection apparatus for detecting vibration of a blade in a rotating blade row of a machine, comprising:
-
(A) a plurality of sensors disposed about said blade row with each sensor being operable to provide an output signal upon relative passage of a blade; (B) signal conditioning means responsive to said sensor output signals and operable to provide respective corresponding sensor pulse signals; (C) means for selecting a particular blade to be monitored; (D) means for sequentially combining all of the sensor pulse signals caused by said selected blade as it passes the respective sensors, to derive a pulse train signal modulated as a function of any vibration of said selected blade; and (E) detection circuitry including FM detection means operable to demodulate said pulse train signal to derive a blade vibration indicative signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification