Bearing unit provided with a sealing device

A bearing unit having a central axis of rotation and comprising:

• a radially outer ring, stationary,
• a radially inner ring, rotatable, defining, with the radially outer ring, a cavity, and
• a sealing device, which is housed in the cavity and includes, in turn:
• a first shield integral with the radially outer ring and which supports a first sealing element,
• a second shield integral with the radially inner ring and which supports a second sealing element,
• the bearing unit being characterized by the fact that the first and the second sealing element are provided with respective first and second shaped surfaces which:
• are axially opposed but not in contact with each other,
• define a plurality of ridges and valleys, where on each shaped surface each ridge is radially alternated with a valley, and
• are radially staggered so that each ridge of the first shaped surface corresponds to a valley of the second shaped surface and each ridge of the second shaped surface corresponds to a valley of the first shaped surface.