Sealing arrangement for cylinder and piston unit, comprising different relation between inner and outer sealing ring and contact surfaces

摘要

The unit comprises at least an inner (3) and outer sealing ring (4), one of them accommodated inside a groove (1b,1c) located at the cylinder (1) and provided with a sealing lip (3a, 4a). The sealing lip (3a, 4a) has an inclined shape rising towards the open side of the cylinder (1) before the piston (2) is inserted. The diameter of the inner ring (3) is smaller than the diameter of the contact surface (2a) whereas the outer ring (4) has a bigger diameter than its contact surface (2b).