Patent attributes
A vibration damper, e.g. for damping retraction or extension springing forces on motor vehicles, includes a pressure medium cylinder in which a piston with a piston rod is axially slidably arranged. The piston divides the cylinder into first and second chambers which contain an electrorheological or magnetorheological fluid as a pressure medium. The two chambers are connected with one another through a throttle gap with at least one field generating element arranged adjacent thereto. The length of the throttle gap is divided by a gap intersection point into a first throttle gap section connected with the first chamber, and a second throttle gap section connected with the second chamber. A non-return check valve is arranged in a bypass gap connected parallel to the first throttle gap section between the gap intersection point and the first chamber.