Floor-concealed door closer

摘要

The door closer includes a hydraulic piston-cylinder system (7,8) whose piston (7) has at least one seal (43) which interacts with the inner wall of the cylinder (8) and can be mounted in a groove (47) on the piston. The groove can be arranged in a bead (46) which is enlarged relative to the piston dia..The bead has an inclined run-up face. It has at least one guide face (49) adjoining the groove and pref. extending right and left. The seal and adjoining guide faces are symmetrical to the transverse centre axis of the piston.