Patent ID: 7234576
Filing Date: 2007-06-26
Classification: B60G,F16F

Abstract:
1. A damper, in particular for motor vehicles, comprising a cylinder adapted to contain a hydraulic fluid, a main piston actuated by a stem defining in the cylinder a first chamber and a second chamber, said second chamber containing the stem, a hydraulic fluid reservoir and a valve placed in the hydraulic fluid flow between the first chamber and the second chamber, said valve comprising a movable valve element cooperating with a seat and means designed to press the valve element onto its seat, filtering means being mounted in parallel with the valve, adapted to generate a filtering control pressure acting on the valve element of the valve, the control pressure depending on the pressure differential at an inlet and at an outlet of the valve, said filtering means comprising a balancing chamber divided into two parts by a movable piston, said movable piston being subjected to the action of a balancing spring means, and wherein, the two parts of the balancing chamber are respectively linked by pipes, on the one hand to the inlet of the valve, itself linked to the first chamber of the cylinder and on the other hand to the outlet of the valve, itself linked to the second chamber of the cylinder and to the reservoir, and said filtering means further compresses a filtering restriction mounted in the pipe linking one of the parts of the balancing chamber to the valve; a filtering pipe also linking said part of the balancing chamber to the valve in order to apply the filtering control pressure prevailing in said part if the balancing chamber to the movable valve element of the valve.