VENTILATED TRICKLE SEAL

摘要

A seal (30) is provided around a shaft (20) extending through a cavity (12) in a hydrogen cooled generator. The seal (30) includes a plurality of brush seal (130) (230) structures adapted to reduce flow to/from the cavity to a level where the risk of creating an explosive mixture of gases is minimized. In an embodiment of the invention, a series of brush seals are provided to interface with the rotary shaft (20) so as to define a seal of minimizing the flow of hydrogen out of the cavity. In one preferred embodiment, the seal (30) is composed of first (130) and second brush seal assemblies (230), each of which is comprised of a plurality of brush seal structures (32). In another embodiment, spring(s) (56) (156) are provided to urge the brush seal structures (52) (54) into sealing engagement with the rotor. If deemed necessary or desirable, a vent outlet (52) is provided in a cavity wall remote from the hydrogen atmosphere, to remove hydrogen that has leaked through the brush seals.