Patent ID: 7407369

Claim:
A zero running clearance system for gas turbine engines, comprising: one or more first rotor assemblies of a gas turbine engine compressor rotatable around an axially extending rotational axis, each first rotor assembly having a plurality of blades with each blade having a tip; one or more first stator assemblies of said gas turbine engine compressor disposed adjacent said one or more first rotor assemblies; one or more first shroud segments having blade seal surfaces disposed radially outside of said one or more first rotor assemblies; one or more second rotor assemblies of a gas turbine engine turbine rotatable around said axially extending rotational axis, each second rotor assembly having a plurality of blades with each blade having a tip; one or more second stator assemblies of said gas turbine engine turbine disposed adjacent said one or more second rotor assemblies; one or more second shroud segments having blade seal surfaces disposed radially outside of said one or more second rotor assemblies; wherein said blade tips and said blade seal surfaces have mating geometries and a clearance distance extending between said blade tips and said blade seal surfaces; and an actuator selectively operable to axially move said first rotor assemblies and said second rotor assemblies to alter said clearance distance; wherein said actuator includes a screw thread device, wherein said screw thread device is mounted such that both said first rotor assemblies and said second rotor assemblies move axially in unison when at least a portion of the screw thread device rotates.