Multiple stage seal for a bearing assembly
A flexible double lipped annular seal includes an anchor segment at a radially outermost portion thereof and having a pocket formed therein. The annular seal includes a branch segment extending axially outward and radially inward from the first leg at an angle. A first lip seal and a second lip seal extend radially inward from the branch segment and have a gap therebetween. The branch segment terminates in a stub segment. The annular seal includes a metallic shield secured to the annular seal and a portion of which seats in the pocket.
1. A bearing assembly, comprising:
an inner member having an outer engagement surface extending between a first end and second end of the inner member;
an outer race having an inner engagement surface, the inner engagement surface being positioned on the outer engagement surface of the inner member and contoured to a shape complementary to the outer engagement surface such that the outer engagement surface is slidably and rotatably engaged with the inner engagement surface;
at least one first annular groove formed in the inner engagement surface, proximate at least one of the first end and the second end;
a flexible double lipped annular seal comprising:
a first anchor segment comprising an axially extending first base defining a radially outermost portion of the first anchor segment, a first leg extending radially inward from the first base and a second leg extending radially inward from the first base, the first leg and the second leg defining a pocket therebetween;
a branch segment extending axially outward and radially inward from the first leg at a first angle relative to a first axial surface of the first leg, a first lip seal extending radially inward from the branch segment and a second lip seal extending radially inward from the branch segment, the first lip seal and the second lip seal having a gap therebetween, the branch segment terminating in a stub segment;
a metallic shield having a radially extending second base and a mid-section extending axially outward and radially inward from the second base at the first angle and a terminus segment extending radially inward from the mid-section; and
the second base of the metallic shield being seated in the pocket, the mid-section being adhered to the branch segment and a portion of the terminus segment being adhered to the stub segment,
at least one second annular groove formed in the inner engagement surface and being positioned axially outward from the first annular groove; and
a scraper seal being seated in the at least one second annular groove, wherein the scraper seal is stiffer than the first lip seal and the second lip seal, the scraper seal configured to flex to conform to a contour of the outer engagement surface to dislodge and remove particles from the outer engagement surface when the inner member is misaligned relative to the outer race.
2. The bearing assembly of claim 1 , wherein the stub segment is spaced apart from the second lip seal and the terminus segment has a radial end that is positioned radially outward from a distal end of the second lip seal and extends radially inward from the stub segment.
3. The bearing assembly of claim 1 , wherein the stub segment is spaced apart from the branch segment and defines a radially inward extending channel and a distal end of the terminus segment is seated in the channel.
4. The bearing assembly of claim 1 , further comprising a second gap located between the flexible double lipped annular seal and the scraper seal, the second gap being filled a with at least one of a lubricant and a sealant material.
5. The bearing assembly of claim 1 , wherein the first gap is filled with at least one of a lubricant and a sealant material.
6. The bearing assembly of claim 1 , further comprising a lubricious liner disposed between the outer engagement surface of the inner member and the inner engagement surface of the outer race.
7. The bearing assembly of claim 1 , wherein the scraper seal comprises a thermoplastic material.
8. The bearing assembly of claim 1 , wherein the scraper seal comprises a second anchor segment that has a shape complementary to the at least one second annular groove and has a stabilizing block extending axially away from the second anchor segment and arranged to form a shoulder with the second anchor segment, and the shoulder seating on an radially inward facing abutment surface of the outer race.
9. The bearing assembly of claim 8 , further comprising a seal leg extending at a second angle relative to an axial face of the scraper seal.
10. The bearing assembly of claim 1 , wherein:
(a) the first base, the branch segment, the first lip seal and the second lip seal are each manufactured from natural rubber, synthetic rubber, felt, PTFE, silicones or a synthetic elastomer polymer; and
(b) the scraper seal is manufactured from a metallic material or a thermoplastic material.