Annular sealing assembly, in particualr for insertion between elements subjected to an offset positioning

A sealing assembly (1) for insertion between first and second mechanical element subjected to possible offset positioning, including a reinforcement ring (8) and at least one elastomeric sealing element (9) in which the reinforcement ring (8) is at least partially embedded, the sealing element (9) including an annular membrane (10) shaped as a truncated-cone sleeve and free from the reinforcement ring, which membrane obliquely extends so as to protrude from the reinforcement ring, towards a symmetry axis (A) of the sealing assembly and ends with at least one annular sealing lip (12) intended to slidingly cooperate with the first mechanical element; the membrane (10) has, in radial direction, a relatively thin thickness, thinner than that of the at least one sealing lip (12), so as to be highly flexible, and a plurality of stiffening ribs (19) obtained in one piece with the membrane (10), as localized thickenings of the membrane, and which extend in the axial direction, parallel to one another, spaced apart from one another to form a crown of longitudinally extending radial projections on membrane (10).