Multi-function fluid seal for dampers and the like

Claim 1

A fluid seal unit for use in retaining fluids within an associated sealed mechanism having first and second relatively movable parts defining at least one of a pair of fluid-receiving and retaining regions within said mechanism, said seal unit, and a first elastomeric seal body bonded to a portion of said casing unit, said first elastomeric seal body being of generally annular form, and having portions defining a primary fluid lip portion and a secondary excluder lip portion, with said primary lip portion having air and oil side frusto-conical surfaces meeting along a generally circular locus to define a seal band adapted to engage one of said first and second parts forming parts of said associated sealed mechanism in snug sealing engagement, said oil side frusto-conical surface being directed in part toward the first of said pair of fluid-retaining sealed regions within said mechanism, and a second, relief valve seal body also bonded to said casing unit at and being defined at least in part by a generally radially outwardly facing annular surface, an at least partially radially inwardly facing surface and a radially extending end face surface joined at its edges to axially inner margins of said outwardly and inwardly facing annular surfaces, said relief valve seal body being adapted to cooperate with a contoured relief valve seating surface forming a portion of said associated sealed mechanism, with said relief valve seal body surface and said seating surface being dimensioned so that said relief valve seal body surface is urged against said seating surface portion by the inherent resiliency of said relief valve seal body, said secondary excluder lip portion also including at least one annular surface adapted to define, in cooperation with one of said first and second movable parts of said sealed mechanism, a generally circular, radially inwardly acting excluder seal band.