Loading patent…
AssigneeSiemens Aktiengesellschaft
InventorViktor Bodlaj
Estimating the term…
A method and apparatus for measuring the height of a blade of a turbine rotor as the rotor is being rotated characterized by deflecting a laser beam at a given deflection frequency across the path of the moving blade so that a portion of the deflected beam will be reflected by the end of the blade, sensing the reflected portion to produce a reflected signal, synchronizing the speed of rotation of the rotor with the frequency of deflection so that the end of the blade and the deflected beam reach the same point simultaneously and applying the reflected laser signal and a reference signal from the laser beam to an electronic analysis system to determine the height of the individual blade. Preferably, the synchronizing is accomplished by sensing the blade frequency, converting it to a converted blade frequency, comparing the converted blade frequency with the frequency of deflection to obtain an error signal and using the error signal to control the speed of rotation of the rotor. By including a counter circuit in the electronic analysis circuit and by sensing a mark on the rotor during each rotation of the rotor, adjustments can be made to either determine the height of each blade in a stage of blades during one revolution or to determine the height of a single individual blade of the stage.
A method for automatic, contactless measurement of the height of individual blades on a rotating turbine rotor comprising rotating the turbine rotor having the blades arranged thereon, deflecting a laser beam from a given path at a known frequency of deflection to move the deflected beam across the path of the moving blade to have a portion of the beam reflected from an end of the blade, sensing the portion of the beam reflected from the end of the blade to create a reflected signal, sychronizing the speed of rotation of the rotor with the frequency of deflection so that the end of the blade and deflected beam reach the same point simultaneously, and applying the reflected signal and a reference signal from the beam to an electronic analysis system to determine the height of the individual blade.
An apparatus for measuring the height of individual blades of a stage of blades of a rotating turbine rotor, comprising means for rotating the rotor, a laser projecting a laser beam, means for obtaining a reference signal from the laser beam, means for deflecting the laser beam across the path of moving blades at a given frequency of deflection, means sensing a portion of the deflected laser beam reflected by an end of the blade to obtain a reflected signal, means synchronizing the speed of rotation of the rotor and a deflecting frequency so that the deflected beam and end of the blade reach the same point simultaneously, and means analyzing the reflected signal and the reference signal to determine the height of the individual blade.
Dependencies are inferred from the claim text.