Patent ID: 11953058
Assignee: AKTIEBOLAGET SKF
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F  B | IPC B  F

Claim 10:
11. A sealing device, for a bearing unit, the bearing unit comprising a stationary radially outer ring and a rotatable radially inner ring, the sealing device comprising:
a first metallic, annular screen comprising a first mounting area, the first mounting area configured to contact by interference the radially inner ring in an assembled configuration;
a second metallic, stationary annular screen comprising a second mounting area, the second mounting area configured to contact by interference the radially outer ring in the assembled configuration;
an annular sealing element made of elastomeric material and integrally supported by the second annular screen, the annular sealing element comprising at least one contacting annular sealing lip projecting from the second screen towards the first screen; and
a non-contacting annular lip extending axially towards a first flange portion of the first annular screen, wherein,
the non-contacting annular lip is disposed radially between a labyrinth seal at an external end of the sealing device and the at least one contacting annular sealing lip at an internal end of the sealing device, and
the non-contacting annular lip and the first flange portion of the first annular screen define a gap between thereto, the gap has an axial dimension of less than 1.3 mm, and
the annular sealing element further comprises a sleeve portion comprising an axially projecting frustoconical spur, and
the first annular screen further comprises a sleeve portion, the sleeve portion of the annular sealing element and the sleeve portion of the first annular screen form together the labyrinth seal, and
between the frustoconical spur, the non-contacting annular lip, and the first flange portion of the first annular screen a first drainage chamber is defined, and
between the non-contacting annular lip and the at least one contacting annular sealing lip a second drainage chamber is defined, and
the first flange portion forms with a first sleeve portion of the first annular screen a step arranged radially on an inside of the first annular screen and arranged axially facing the second annular screen and the annular sealing element, wherein a connecting radius of the step is between 0.7 mm and 1.2 mm, and
the at least one annular sealing lip is a pair of annular sealing lips and wherein a first radially outer lip interacts slidingly with a fourth flange portion of the first annular screen and a second radially inner lip of the pair of annular sealing lips interacts slidingly with an inclined connecting portion of the first mounting area, the inclined connection portion being inclined axially with respect to an axis of rotation of the bearing unit, and
the annular sealing element is provided with a third sealing lip extending towards a fourth sleeve portion of the first annular screen, the fourth sleeve portion extending axially away from the inclined connection portion towards the second annular screen.