Patent attributes
The derailleur has a damper that breaks the angular movements of a chain guide. Variable volume chambers in the damper are filled with a damping fluid and connected through a controlled fluid passage system so that fluid flows between chambers in response to angular movement of the chain guide. The damper comprises a dividing body in a mobile body coaxial to the axis X, mechanically constrained so that each rotation of the dividing body about the axis X is accompanied by a translation of the dividing body along the axis X. The dividing body is mechanically constrained to the chain guide and moves with it in the angular direction about the axis X. The chambers are formed in the mobile body on opposite sides of the dividing body and change volume in opposite directions when the dividing body moves along the axis X.