Patent ID: 8074997
Filing Date: 2011-12-13
Classification: F01D,F16J,Y02T

Abstract:
1. An air-riding seal system comprising: (a) a cylindrical-shaped carrier disposed about a rotatable shaft with a seal runner extending therefrom; (b) a primary seal assembly including at least two arcuate seal segments which form a ring-shaped seal, each said arcuate seal segment contacts said cylindrical-shaped carrier and is movable thereon, each said arcuate seal segment having a cross section that is substantially L-shaped and a surface with a step face and an arcuate dam, said surface disposed opposite of a sealing surface along said seal runner, each said arcuate seal segment having an arcuate support arm disposed at one end thereof and having a tooth disposed at another end adjacent to an outermost circumferential surface along said seal runner, each said tooth and said outermost circumferential surface separated by a gap; (c) a secondary seal ring disposed between and contacting said primary seal assembly and a housing structure so as to form a bore seal and a face seal therewith; (d) a structure along each said surface of said primary seal assembly which increases stiffness of a thin film between each said surface and said sealing surface, said structure being at least one hydrodynamic pocket disposed along said arcuate dam or at least two radial dams disposed along said surface in an outward radial arrangement with respect to said arcuate dam; (e) a first coil spring disposed between each said arcuate seal segment and a portion of said housing structure, said first coil spring urges said arcuate seal segment away from said seal runner in response to pressure condition adjacent to said air-riding seal system; and (f) a second coil spring disposed between each said arcuate seal segment and said cylindrical-shaped carrier, said second coil spring biases said arcuate seal segment toward said seal runner.