Patent ID: 8925927
Filing Date: 2015-01-06
Classification: F16J

Abstract:
1. A dynamic seal comprising: a lubricant side; a non-lubricant side; an elastomeric sealing portion operable to engage with and seal against a shaft, said elastomeric sealing portion including an active surface communicating with said non-lubricant side and a seal lip at an end thereof, said seal lip facing said lubricant side, said seal lip defining an opening in which a shaft can be disposed, and said active surface operable to engage with and seal against a shaft disposed in said opening; and a plurality of non-intersecting grooves each extending along said active surface and stopping short of said seal lip, said grooves each having a beginning point and a termination point adjacent said seal lip and operable to capture lubricant that leaks past said seal lip and pump said lubricant toward the associated termination point and back into said lubricant side due to relative rotation between said active surface and a shaft, wherein each of said grooves has an induction zone characterized as having a constant cross-sectional area as said groove extends along said active surface and operable to increase a fluid pressure of a lubricant therein as a function of distance toward said lubricant side at a first rate, each of said grooves has a booster zone characterized as having a reducing cross-sectional area as said groove extends along said active surface and operable to increase a fluid pressure of a lubricant therein as a function of distance toward said lubricant side at a second rate greater than the first rate, said cross-sectional area of said grooves in said booster zone diminishes as said grooves extend toward said termination point and away from said induction zone, and said booster zone is located between said seal lip and said induction zone; and a dam disposed between said seal lip and said termination points of said grooves, said dam sealing against a shaft disposed in said opening, and a portion of said dam is dislodged from the shaft when lubricant is pumped into said lubricant side by said grooves.