VIBRATION DAMPING STRUCTURE FOR MOVING BLADE

摘要

PROBLEM TO BE SOLVED: To eliminate a wire from a gas passage and improve aerodynamic performance and prevent the breakage of moving blades fixed to a rotor by passing a wire in the root portions of moving blades projecting from the surface of the rotor in the vibration damping structure of the rotor moving blades through which the wire is stretched. SOLUTION: A plurality of groves 3 are made on the outer surface of a rotor 1 and the root portions 4 of moving blades 2 are fitted in the grooves 3. The root portion 4 has a fitting portion 5 fitted in the groove 3 and an exposed portion 7 projecting outward in the radial direction from the surface 6 of the rotor 1. A through hole 10 is made in the exposed portion 7 of the root portion 4 and a wire 11 is passed therethrough. Since there is a small gap between the groove 3 and the fitting portion 5, the moving blade 2 is vibrated about the fitting portion 5 as a fulcrum by the centrifugal force based on the rotation of the rotor 1 and gas pressure, and the inner surface of the through hole 10 is rubbed on the wire 11 to damp the vibration of the moving blade 2 by the friction resistance.