Patent ID: 7766137

Claim:
A shock absorber including a cylinder, a piston displaceable within the cylinder, a piston rod connected to said piston, and a nonreturn valve, said piston dividing said cylinder into a first chamber including said piston rod and a second chamber, said nonreturn valve comprising: an elastically flexible valve plate; a valve seat plate having an opening, the opening having an edge defined by the valve seat plate, the valve seat plate being less flexible than the valve plate; and a spacer between the valve plate and the valve seat plate that keeps the valve plate spaced from the valve seat plate when the nonreturn valve is open, wherein at a first flow velocity through said nonreturn valve, the nonreturn valve substantially does not close, at a second flow velocity higher than the first flow velocity from the first chamber to the second chamber through the nonreturn valve, the nonreturn valve closes in a first closing state, wherein the valve plate contacts the edge of the opening of the valve seat plate at a first position, at a third flow velocity higher than the second flow velocity from the first chamber to the second chamber through the nonreturn valve, the nonreturn valve closes in a second closing state, wherein the valve plate contacts the edge of the opening of the valve seat plate at both the first position and a second position, and in the first and second closing states, the valve plate does not contact the edge of the opening of the valve seat plate at a third position immediately adjacent the spacer.