Patent ID: 8132654

Claim:
A hydraulic damper comprising a tube filled with working fluid; a piston assembly slidably positioned inside the tube and including a compression valve assembly and a rebound valve assembly; a piston rod attached to the piston assembly and extending out a first end of the tube; a fluid compensation chamber located outside of the tube; a base valve assembly at a second end of the tube for controlling the flow of working fluid between the tube and the compensation chamber; and a compression valve module attached to the base valve assembly inside the tube; wherein said compression valve module comprises a substantially rigid disc having an outside diameter less than the inner diameter of the tube, an outer tubular member secured to the tube, an inner cylindrical member substantially coaxial with the outer tubular member, at least one radially extending bridge member securing the inner cylindrical member to the outer tubular member, an abutment surface for the disc defined by at least one of the inner cylindrical member and the outer tubular member, a bolt secured to at least one of the inner cylindrical member and the outer tubular member and including a bolt shaft passing through the inner cylindrical member and the disc and a head presenting a bottom surface defining a disc open position spaced from the abutment surface in an axial direction and an annular recessed groove that directly adjoins the outer surface of the bolt shaft, and a spring acting on the disc to bias the disc to its open position, wherein the disc is movable between the open position to allow free fluid flow through the compression valve module and the abutment surface to substantially prevent or restrict fluid flow through at least one flow passage.