COMBINED GREASE SEAL-DIRT SHIELD

• US 3,838,898 A
• Filed: 07/30/1973
• Issued: 10/01/1974
• Est. Priority Date: 07/30/1973
• Status: Expired due to Term

• Current Assignee: Melvyn R. Bird
• Original Assignee: Melvyn R. Bird
• Inventors: Bird, Melvyn R.
• Primary Examiner(s): Antonakas, Manuel A.
• Assistant Examiner(s): Susko, Frank
• Application Number:
  US05/384,142
• Time in Patent Office: 428 Days
• Field of Search: 308/187.1,187.2,277
• US Class Current: 384/487
• CPC Class Codes: F16C 33/7873 with a single sealing ring of generally L-shaped cross-section

Abstract

A combined grease seal-dirt shield for an antifriction bearing or the like comprises a unit-handled assembly which includes a scraper ring for cooperation with a land of the inner race ring to protect the grease seal from dirt and other deleterious matter. The scraper ring is radially floatable thus permitting a close running fit with the inner race land. The scraper ring is also flared and axially movable into an operative association with the grease seal to increase the lip sealing pressure responsive to dirt build-up between the scraper ring and the case.

Claims

1. A combined grease seal-dirt shield for an antifriction bearing having relatively rotatable inner and outer race rings radially spaced by antifriction elements disposed therebetween comprising, an annular case having a cylindrical wall adapted to engage a land of an outer race ring with a press fit and a generally radial inwardly extending end wall contiguous with an end of said cylindrical wall, an annular L-shaped insert having a flange and a rim secured in a nesting relationship in said outer annular case with said rim engaging a surface of said end wall and spacing said flange from said end wall of said annular case, an elastomeric grease seal having a body disposed between said flange and said end wall and a thinner, depending annular flexible lip adapted to sealingly engage a land of an inner race ring. said body portion having an outer peripheral surface bonded to an inner face of said rim, a first end surface bonded to a face of said flange contiguous with said inner face, and a second end face abutting said surface of said end wall, said body having a plurality of radial slots in said second end face extending from an inner circumferential surface of said body, and a scraper ring having an inner circumferential surface adapted to encircle and engage a land of an inner ring with a close running fit, said scraper ring having a plurality of radial, outwardly extending fingers disposed in said radial slots, said fingers having free ends and root ends spaced radially inwardly of the outer ends of said slots and said inner circumferential surface of said body respectively when said scraper ring is concentric with said body whereby said scraper ring is substantially non-rotatable with respect to said case while being radially adjustable with respect to said case to compensate for eccentricities and run out between an outer race ring land of an antifriction bearing on which said case is mounted and an inner race ring land of said antifriction bearing which said inner circumferential surface of said scraper ring engages.

2. A combined grease seal-dirt shield as defined in claim 1 wherein said scraper ring has a flared inner marginal portion angled away from said lip of said grease seal and wherein said inner circumferential surface of said scraper ring which is adapted to encircle and engage a land of an inner race ring with a close running fit is a cylindrical surface of said inner marginal portion.

3. A combined grease seal-dirt shield as defined in claim 2 wherein said end wall of said annular case terminates with an inner peripheral surface having a diameter slightly larger than the diameter of said inner circumferential surface of said scraper ring whereby said end wall is adapted to cooperate with a land of an inner race ring to prevent larger particles of dirt traveling along the land from reaching said scraper ring.

4. A combined grease seal-dirt shield as defined in claim 3 wherein said end wall of said annular case has a flat portion contiguous with said cylindrical wall which extends radially inwardly of the root ends of said fingers on said scraper ring sufficiently to overlap said root ends when said scraper ring is eccentrIcally located with respect to said end wall up to an amount limited by said inner peripheral surface of said end wall and said cylindrical surface of said scraper ring being tangentially aligned.

5. A combined grease seal-dirt shield as defined in claim 4 wherein said end wall of said annular case has a flared inner marginal portion angled away from said scraper ring and forming a wedge-shaped space with said flared inner marginal portion of said scraper ring which decreases in width in the radially outward direction.

6. In an antifriction bearing or the like having relatively rotatable inner and outer race rings radially spaced by antifriction elements disposed therebetween, a combined grease seal-dirt shield comprising, an outer annular case having a cylindrical wall adapted to engage a land of said outer race ring with a press fit and a generally radial inwardly extending end wall contiguous with an end of said cylindrical wall, said end wall having an inner circumferential edge encircling and lying in close proximity to a land of said inner race ring, an annular L-shaped insert having a flange and a rim secured in a nesting relationship in said annular case with said rim engaging a surface of said end wall and spacing said flange from said end wall of said outer annular case, an elastomeric grease seal having a body disposed between said flange and said end wall and a thinner, depending annular flexible lip in a lightly biased sealing engagement with said land of said inner race ring, said body portion having an outer peripheral surface bonded to an inner face of said rim of said insert along its entire length, a first end surface bonded to a face of said flange contiguous with said inner face, and a second end face abutting said surface of said end wall, said body having a plurality of radial slots in said second end face extending radially completely through said body from an inner circumferential surface thereof to said outer peripheral surface, and a scraper ring having a flared inner marginal portion terminating in an inner cylindrical surface having a diameter less than the diameter of said edge of said case end wall, said cylindrical surface encircling and engaging said land of said inner race ring with a close running fit, said scraper ring having a plurality of radial, outwardly extending fingers disposed in said radial slots, said fingers having free ends and root ends spaced radially inwardly of the outer ends of said slots and said inner circumferential surface of said body respectively when said annular scraper ring is concentric with said body whereby said scraper ring is substantially non-rotatable with respect to said outer race ring and radially adjustable with respect thereto to compensate for eccentricities and run out between said race rings during operation of said anitfriction bearing.

7. In an antifriction bearing or the like having relatively rotatable inner and outer race rings radially spaced by antifriction elements disposed therebetween, a combined grease seal-dirt shield as defined in claim 6 wherein said end wall of said annular case has a flat portion contiguous with said cylindrical wall which extends radially inwardly of the root ends of said fingers on said scraper ring sufficiently to overlap said root ends when said scraper ring is eccentrically located with respect to said end wall up to an amount limited by said inner peripheral surface of said end wall and said cylindrical surface of said scraper ring being tangentially aligned.

8. A combined grease seal-dirt shield as defined in claim 7 wherein said end wall of said annular case has a flared inner marginal portion angled away from said scraper ring and forming a wedge-shaped space with said flared inner marginal portion of said scraper ring which decreases in width in the radially outward direction and wherein said scraper ring is axially movable into operative relationship with said annular flexible lip to increase the sealing engagement witH said land of said inner race ring responsive to dirt build-up in said wedge-shaped space.