Fluid transfer seal for transferring fluid across a rotating boundary

Claim 1

A fluid transfer system for a gas turbine engine, the engine having a stator and a coaxial rotor positioned for rotation about at least a portion of an axial extent of the stator, the fluid transfer system comprising: at least one annular channel formed about a circumference of the axial extent of the stator adjacent the rotor; means coupled to the stator for supplying pressurized fluid to said channel; an annular seal carrier disposed within said channel, said carrier having an outer circumferential slot facing the rotor and an inner circumferential slot facing the stator and a plurality of spaced apertures extending through said carrier from said inner slot to said outer slot, an annular land formed on each axially opposite side edges of said carrier, each land facing a corresponding radial wall of said channel, said carrier having an edge-to-edge dimension such that spacing between each land and its adjacent channel radial wall is such as to restrict fluid flow past each land to a predetermined minimum rate; first and second outer circumferential grooves formed about said carrier on opposing sides of said outer circumferential slot; first and second annular sealing rings, each of said rings being positioned in a corresponding one of said grooves; means for coupling fluid from said outer circumferential slot to each of said grooves, the fluid pushing each ring into sealing relationship with a side of its corresponding groove and into sealing relationship with the rotor for containing fluid within boundaries defined by said rings; and means in the rotor adjacent said carrier for receiving fluid from said outer circumferential slot.