Follower piston for e.g. pharmacy field, has anti-return units preventing displacement of piston inside shaft of fluid product tank in response to overpressure in tank, and formed with sealing lip in monoblock manner

摘要

The piston (P) has a sealing lip (11) that slides inside a shaft (2) of a fluid product tank (R) in a sealed manner, and anti-return units for preventing displacement of the piston inside the shaft in response to an overpressure in the tank. The anti-return units are formed with the sealing lip in a monoblock manner, and constituted of a locking ring (13), a flexible membrane (14), a flexible skirt (15) and an annular locking ridge (16).