Patent ID: 7688081

Claim:
An apparatus for determining a clearance between a rotor and a stator, the rotor having a plurality of rotor blades mounted on the rotor and the rotor blades have rotor blade tips, the stator having a stator casing and a stator lining, the stator lining is mounted on the stator casing, the stator lining is movable relative to the stator casing, the stator lining having an abradable material, the apparatus comprising at least one probe to measure the clearance between the rotor blade tips and the stator lining, a first portion of the at least one probe is arranged within the stator lining, a tip of the first portion of the at least one probe is arranged flush with the surface of the abradable material, the tip of the first portion of the at least one probe comprises an abradable material, a second portion of the at least one probe is secured to the stator casing, a wire-less and connector-less coupling to transmit a measurement signal from the first portion to the second portion of the at least one probe to allow movement of the stator lining relative to the stator casing.