US 5,203,673 A · Tip clearance control apparatus for a turbo-machine blade

Abstract

An apparatus is provided for controlling rotating blade tip clearance in a turbo-machine utilizing conical tipped blades. The apparatus comprises an approximately conical blade ring mounted for axially sliding displacement in the turbo-machine cylinder. The conical blade ring encircles the tips of the rotating blades and forms a blade tip clearance therebetween. The tip clearance is controlled during operation of the turbo-machine by axially displacing the conical blade ring. Piston cylinders, actuated by pressurized fluid extracted from the turbo-machine, are used to displace the blade ring. Springs, adapted to bias the blade ring into a position of increased tip clearance, oppose the piston cylinder so that failure of the piston cylinder will not result in a loss of tip clearance. A blade tip clearance sensor transmits information on the tip clearance to a controller that automatically adjusts the blade ring axial position to continuously maintain the optimum tip clearance by regulating the pressure of the fluid supplied to the piston cylinders.

Claims19

Dependent claims

A turbo-machine, comprising:

a) a centrally disposed rotor having a row of rotating blades extending radially therefrom, each of said blades having an approximately conical tip portion;
b) a stationary cylinder enclosing said rotor and containing a pressurized working fluid flowing therethrough, an approximately conical blade ring mounted for axially sliding displacement in said cylinder, said conical blade ring encircling said blade tips and forming a blade tip clearance therebetween;
and
c) means for continuously adjusting said tip clearance during operation of said turbo-machine so as to maintain said tip clearance within a predetermined range, said tip clearance continuous adjusting means including:
(i) first force generating means for generating a force for axially displacing said conical blade ring relative to said cylinder in response to the pressure of said working fluid supplied to said first force generating means, and
(ii) means for extracting said pressurized working fluid and supplying said fluid extracted to said first force generating means for operation thereof, whereby said tip clearance automatically responds to changes in said pressure of said working fluid.

3 more elements

A turbo-machine, comprising:

a) a centrally disposed rotor having a row of rotating blades extending radially therefrom, each of said blades having an approximately conical tip portion;
b) a stationary cylinder enclosing said rotor;
c) a blade ring having an approximately conical surface encircling said blade tips and forming a blade tip clearance therebetween;
d) means for mounting said blade ring in said cylinder so that said blade ring is capable of axial displacement relative to said cylinder, said mounting means including:
(i) an approximately radially extending rib attached to said conical blade ring and having a plurality of holes formed therein, and
(ii) a plurality of approximately axially oriented support members attached to said cylinder, a respective one of said support members disposed in each of said holes;
and
e) means for continuously adjusting said tip clearance by axially displacing said blade ring during operation of said turbo-machine, thereby maintaining said tip clearance within a predetermined range, said tip clearance continuous adjusting means including:
(i) a plurality of springs for generating an axial force biasing said blade ring in a first axial direction, and
(ii) a piston cylinder supplied with pressurized fluid for applying an axial force in a second axial direction opposing said springs, whereby said tip clearance is adjusted by balancing said piston cylinder and spring forces.

7 more elements

Dependencies are inferred from the claim text.

Tip clearance control apparatus for a turbo-machine blade

Life of this patent

Tip clearance control apparatus for a turbo-machine blade

Life of this patent

Abstract

Claims19