US Patent 11946527 Vibration damper having a pump assembly

A vibration damper comprising a working cylinder, which is subdivided by an axially movable piston on a piston rod into a first and a second working chamber filled with a damping medium is disclosed. The vibration damper has at least one compensating reservoir for receiving the damping medium displaced by the piston rod. There is a flow connection between the two working chambers, in which connection there is incorporated a pump assembly. The pump assembly has a fluctuation in the delivery volume with a constant power supply. At least one pulsation accumulator is arranged within the flow connection, wherein the volume and spring rate of the pulsation accumulator are matched to a frequency of a fluctuation of the delivery volume of the pump assembly.