Patent ID: 11897283
Assignee: AKTIEBOLAGET SKF
Field: Mechanical elements (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 13:
14. A bearing unit, comprising:
a flanged first radially inner, rotatable, ring;
a radially outer, stationary, ring;
a second radially inner ring, rotatable, mounted on, and integral with the flanged radially inner ring;
a plurality of rolling bodies interposed between the radially outer ring and both the first and second radially inner rings; and
a sealing device disposed in a cavity defined by the flanged first inner ring and the outer ring, the sealing device comprising:
a first metal screen affixed to the radially outer ring, comprising:
an annular shaped portion; and
a cylindrical portion, the cylindrical portion being radially external with respect to the annular shaped portion;

an elastomer coating comprising:
an annular shaped elastomeric portion;
a cylindrical elastomeric portion;
a contacting lip radially internal with respect to the cylindrical elastomeric portion and axially external with respect to the annular shaped portion; and
a non-contacting lip extending radially and internally from the cylindrical elastomeric portion wherein the elastomer coating is co-moulded on the first screen and positioned radially external and axially external with respect to the first metal screen;

a c-Shaped second metal screen comprising a radially outer wing and affixed to the flanged first radially inner ring,
wherein the contacting lip is configured to make sliding contact with a surface of the c-shaped second metal screen,
the radially outer wing of the second metal screen and the non-contacting lip define between them a first radial labyrinth seal,
an annular surface of the flanged inner ring, a cylindrical surface of the flanged inner ring, a connecting radius connecting the annular surface of the flanged inner ring the cylindrical surface of the flanged inner ring, the c-shaped metal screen, and the cylindrical elastomer portion define between them a cavity configured to contain and expel contaminants by subjecting the contaminants to vertical motion during use, and
a volume of the cavity is proportional to a length of the connecting radius.