Energy saving seal with vacuum induced counter-balance and rocking feature

摘要

A seal includes an annular mounting portion having a bellows portion extending axially and radially inward from the mounting portion. An axial leg extends axially from the bellows portion. A lay down sealing lip extends radially inward and axially from an end of the axial leg. A dust lip extends from the end of the axial leg in a direction opposite the lay down sealing lip. When the oil side is under negative pressure and when the lay down sealing lip begins to lift radially off the shaft there is a counterbalance force applied to the axial leg through the bellows geometry which maintains the lay down sealing lip in contact with the shaft. In addition, the seal is designed to be flexible enough that the oil side vacuum “rocks” the seal bringing the dust lip into contact with the shaft and blocking airflow.