Patent ID: 8777570

Claim:
An air cooled stator vane for a gas turbine engine comprising: an airfoil extending between an inner diameter endwall and an outer diameter endwall; an impingement cover plate secured to a backside of each endwall to form an impingement chamber for backside cooling of the endwall; a plurality of impingement cooling holes formed within the two cover plates; a diffusion slot opening onto a hot surface of each of the two endwalls; the diffusion slot having a serpentine flow channel upstream of the diffusion slot and a metering inlet hole upstream of the serpentine flow channel; the metering inlet hole is connected to the impingement chamber to supply cooling air to the diffusion slot; the diffusion slot is formed into a row of diffusion slots and serpentine flow channels each separated by a rib; and, each separated serpentine flow channel and diffusion slot having a metering inlet hole connected to supply cooling air to the diffusion slot.