February 28, 2006

A hydrodynamic face seal 100 for sealing between the cylinder head 300 and rotating sleeve 200 of a rotating liner engine. The face of the face seal provides a sealing zone 130 for maintaining a lubricant layer of about 2 micrometers between the face seal and the sleeve; and a loading zone 132. The loading zone includes hydrodynamic lift features such as inclined pads 150 or recessed step pads 152. Oil is supplied to annular oil supply passage 142 between the sealing zone and the loading zone, and flows from the annular oil supply passage to radial passages 144 located between the step pads. A spring pre-load is provided to the seal. An outer secondary seal 190 is provided to contain the lubricant. One or more inner secondary seals is provided to contain lubricant and combustion gases. Spiral oil pumping grooves may be provided.

24

February 28, 2006

10/821,672

April 9, 2004

123/43R   123/190.12 123/190.17 123/314 123/59.3 123/65VS 123/80C 277/399 277/400

F01L   7/02   (20060101)  

RELATED APPLICATIONS This application is related to and claims priority from applicants' U.S. Provisional Patent Application No. 60/461,496 filed Apr. 9, 2003.

123/43R-43C   123/59.3   123/65V   123/65VA   123/65VS   123/312   123/313   123/314   123/8   123/193.2   123/193   123/41.83   123/41   123/196V   277/399   277/400   277/401   277/408