Patent ID: 7198275

Claim:
An annular sealing and replenishment cup with axis Δ, which is intended to be positioned between a hydraulic cylinder ( 3 ) and piston ( 4 ) and which has a <<U>> axial section comprising: a static branch ( 10 ) defining a static sealing annular lip ( 11 ), a dynamic branch ( 12 ) defining a dynamic sealing annular lip ( 13 ), and a core ( 14 ) connecting the static ( 10 ) and dynamic ( 12 ) branches and defining an annular bead ( 15 ) opposite the lips, wherein the core ( 14 ) includes a rotation area and a stiffness area, rotation area defined by a first connecting surface ( 24 ) adjacent the static branch ( 10 ), located opposite the bead ( 15 ), and having a concave shape corresponding to a local reduction in the thicknesses of the static branch ( 10 ) and of the core ( 14 ) at the connecting region between the static branch ( 10 ) and the core ( 14 ), the stiffness area having a core thickness greater than the rotation area and a second connecting surface between the first connecting surface ( 24 ) and the dynamic branch ( 12 ), the rotation area ( 21 ) allowing the dynamic branch ( 12 ) and the core ( 14 ) as a whole to be displaced relative to the static branch.