Patent ID: 8608430

Claim:
A turbine stator vane having an airfoil comprising: a main support spar having an inner surface forming a cooling air supply cavity and an outer surface having a series of interconnected chordwise extending impingement chambers that extend from a leading edge region to a trailing edge region; a collection chamber connected to each impingement chamber through a plurality of impingement cooling air holes; a downstream collection chamber connected to an upstream impingement chamber through a return air slot; a first cooling air feed hole connected to the cooling air supply cavity and to a first in a series of the collection chambers located on a pressure side wall of a leading edge of the airfoil; a second cooling air feed hole connected to the cooling air supply cavity and to a first in a series of the collection chambers located on a suction side wall of the leading edge of the airfoil; a first exit hole opening on the pressure side wall of the airfoil in the trailing edge region and connected to a last in the series of impingement chambers located on the pressure side wall; and, a second exit hole opening on the suction side wall of the airfoil in the trailing edge region and connected to a last in the series of impingement chambers located on the suction side wall.