Patent ID: 8560266

Claim:
A turbine machine comprising: a rotor having a plurality of rotor blades; a rotor housing surrounding the rotor and the rotor blades and thereby defining a rotor gap d therebetween at least in sections; a gap measuring system operatively connected to a capacitive sensor device for determining of the measured capacitance values characterized by the rotor gap d; the capacitive sensor device including an electrode and a counterelectrode; wherein the rotor and the rotor blades are connected as the electrode of the sensor device; and wherein at least one part of the rotor housing is connected as the counterelectrode; wherein the rotor housing further includes at least one inner coating or liner made of an electrically conducting material that is disposed on a wall of the rotor housing facing the rotor and the rotor blades at least in segments and said at least one inner coating or liner is connected as the counterelectrode; and a cladding disposed between the inner coating or the liner and the rotor housing, the cladding being galvanically insulated from the inner coating or liner and the rotor housing by insulation; and wherein the gap-measuring system is additionally coupled to the cladding and is designed to determine the capacitance values C between the cladding and the rotor housing.