Abstract A shaft seal having converging frusto-conical faces defining an annular sealing edge for contacting a rotatable shaft and thereby preventing leakage of oil from the oil side of the sealing edge to the atmospheric side of the sealing edge, the frusto-conical face on the atmospheric side of the sealing edge being formed with oblique pumping ribs having helical crests lying on a cylinder of substantially the same diameter as the sealing edge, said pumping ribs being operative to sweep oil leakage past the sealing edge back to the oil side. Preferably the pumping ribs are miniscule in size so that they will wear away and disappear during a fraction of the useful life of the seal when the sealing edge has worn itself to a leak-proof fit on the shaft to thus eliminate, at a predetermined wear-in point, the pumping action of such ribs so that dirt and dust is not carried from the atmospheric side to the oil side.
A seal for a rotating shaft comprising an elastomeric sealing ring having converging frusto-conical faces defining an annular sealing edge therebetween; one face on one side of said sealing edge having a circumferential series of oblique pumping ribs having helical crests lying on a cylinder of substantially the same diameter as said sealing edge and merging therewith to define wedge shaped pumping spaces operative during rotation of a shaft contacted by said sealing edge and crests to pump oil leaking past said sealing edge from the other side thereof back to said other side; said pumping ribs being in the form of triangular pyramids whose lateral edges merge with said sealing edge, one of the lateral edges of said pyramids constituting said crests.
Claim 2
Dependent Claim
123 words
A seal for a rotating shaft comprising an elastomeric sealing ring having converging frusto-conical faces defining an annular sealing edge therebetween; one face on one side of said sealing edge having a circumferential series of oblique pumping ribs having helical crests lying on a cylinder of substantially the same diameter as said sealing edge and merging therewith to define wedge shaped pumping spaces operative during rotation of a shaft contacted by said sealing edge and crests to pump oil leaking past said sealing edge from the other side thereof back to said other side; said pumping ribs being in the form of triangular pyramids whose lateral edges merge with said sealing edge, one of the lateral edges of said pyramids constituting said crests.
Claim 3
Dependent Claim
50 words
The seal of claim 1 wherein one lateral face of said pyramids constituting a wall of the respective wedge-shape spaces is inclined at an acute angle with respect to the shaft surface to tend to sweep leakage oil radially toward the shaft as well as axially toward such other side.