Low-friction sealing device and rolling bearing equipped therewith

A rolling bearing having a sealing device between a first and a second bearing part for forming a wheel hub assembly, the bearing parts being rotatable relative to each other around an axis of symmetry (A) of the sealing device and forming therebetween both an axial space and a radial space with respect to the axis of symmetry, the sealing device comprising:

• a first annular shield having a first mounting section for attachment to the first bearing part, the first annular shield rotating around the symmetry axis;
• a second annular shield coaxial with the first shield and having a second mounting section for attachment to the second bearing part, the second annular shield being stationary;
• and
• an annular sealing element made of an elastomeric material and integrally carried by second annular shield, the annular sealing element having at least a first and a second annular sealing lip axially and radially projecting from the second shield toward the first shield;
• wherein
• the first annular shield provides a peripheral section radially opposite to the first mounting section and having a first and a second axially extending sleeve portions connected to each other by a radially extending first flange portion, the first sleeve portion being radially closer to the first mounting section than the second sleeve portion and the first flange portion forming with the first sleeve portion a step arranged radially inside the first annular shield and facing the second annular shield and the annular sealing element, which is supported by the second shield on a first side thereof facing the first shield;
• the first sleeve portion is housed within the axial space while the second sleeve portion extends radially on the outside of the second bearing part;
• the second annular shield provides a carrier section radially opposite to the second mounting section, the carrier section comprising a second flange portion radially extending towards the first mounting section and carrying the first and second annular sealing lip and a conically truncated intermediate portion connecting the second flange portion to the second mounting portion and radially and axially projecting from the second mounting portion towards the first mounting portion within the axial space, the intermediate portion being arranged partially radially inside of the first sleeve portion, directed radially inwards and axially positioned at the step formed by the first flange portion and the first sleeve portion, arranged radially between the step and the second flange portion;
• and
• the second mounting section being arranged radially on the inside of the second sleeve portion and partly within the second sleeve portion, the second mounting section comprising a third flange portion extending radially from the intermediate portion and a third sleeve portion extending axially from the third flange portion on the side opposite to the first shield and arranged radially adjacent to the second sleeve portion;
• a corresponding sleeve portion of the annular sealing element covering the third sleeve portion on the side facing the first shield and forming with the second sleeve portion a radial gap defining along the whole length of axially superimposed stretches of the second and third sleeve portion an axially oriented labyrinth seal.