Hydrodynamic rotary seal

An annular hydrodynamic sealing assembly comprising:

• A. a first machine component (109) defining at least a portion of a lubricant chamber containing a lubricating fluid (121);
• B. a second machine component (118) having a relatively rotatable surface (115);
• C. an annular hydrodynamic seal (103) defining a sealed partition between said lubricating fluid (121) and a fluid environment (124), comprising:
• i. at least one resilient annular dynamic sealing lip (127) having at least one annular sloping dynamic sealing surface (140) and having a generally circular dynamic exclusionary intersection (139) facing the fluid environment (124) for preventing intrusion of the fluid environment (124) into said lubricating fluid (121);
• ii. an annular static sealing surface (131) defining a static sealing interface with the first machine component (109);
• iii. at least one energizer feature (163);
• D. Said at least one energizer feature (163) compressing at least a portion of said at least one annular sloping dynamic sealing surface (140) into sealing relation with said relatively rotatable surface (115), said at least a portion of said at least one annular sloping dynamic sealing surface (140) being deformed by and assuming the configuration of said relatively rotatable surface (115) and defining a dynamic sealing interface establishing an interfacial contact footprint having varying width (W) throughout the circumference thereof, said interfacial contact footprint having a first footprint edge (157) facing the lubricant chamber and the lubricating fluid (121) and having a second generally circular footprint edge (160) facing the fluid environment (124);
• E. said at least one resilient annular dynamic sealing lip (127) defining a hydrodynamic wedging angle with respect to said relatively rotatable surface (115) proximate said first footprint edge (157);
• and
• F. said at least one resilient annular dynamic sealing lip (127) hydrodynamically wedging a lubricating film of the lubricating fluid (121) into said dynamic sealing interface in response to relative rotational velocity, causing said lubricating film to migrate within said dynamic sealing interface toward said second generally circular footprint edge (160) and into the fluid environment (124).

An annular hydrodynamic seal (103) for sealing between a first machine component (109) and a second machine component (118) having a relatively rotatable surface (115) and defining a sealed partition between a lubricant chamber of the first machine component (109) having a first fluid (121) and an environment having a second fluid (124), comprising:

• A. an annular seal body (104) having a first seal end (133) and a second seal end (136);
• B. at least one resilient annular dynamic sealing lip (127) having an at least one annular sloping dynamic sealing surface (140) and having at least one dynamic exclusionary intersection (139 for facing and preventing intrusion of the second fluid (124);
• C. upon compression of said at least one resilient annular dynamic sealing lip (127) against the relatively rotatable surface (115) at least a portion of said at least one annular sloping dynamic sealing surface (140) being deformed by and assuming the configuration of the relatively rotatable surface (15) and defining a dynamic sealing interface establishing an interfacial contact footprint having varying width (W) throughout the circumference thereof and having a first footprint edge (157) facing the first fluid (121) within the lubricant chamber and a second footprint edge (160) facing the second fluid (124);
• D. an annular static sealing surface (131) defining a static sealing interface with the first machine component (109);
• E. said second seal end (136) defining an annular recess (167) intermediate said at least one resilient annular dynamic sealing lip (127) and said annular static sealing surface (131);
• and
• F. said at least one resilient annular dynamic sealing lip (127) defining a hydrodynamic wedging angle with respect to the relatively rotatable surface (115) for hydrodynamically wedging a lubricating film of the first fluid (121) into said dynamic sealing interface in response to relative rotational velocity, causing the lubricating film to migrate within said dynamic sealing interface toward the second footprint edge (160) and into the second fluid (124).