Patent ID: 8201669

Claim:
An amplitude sensitive damper apparatus provided with an amplitude sensitive valve unit to vary a damping force characteristic according to a wheel stroke size of a vehicle, the apparatus comprising: a plug coupled to a piston rod to form a spring groove with the piston rod in a predetermined section wherein the spring groove is formed to be radially reduced with a predetermined depth along the piston rod; a spool member configured and dimensioned to cover the spring groove and the plug and slidably coupled to the piston rod to move up and down along the piston rod, wherein the spool member includes a supporting portion that protrudes toward and is slidably engaged with the piston rod from a middle portion of an inner surface of the spool member in the spring groove; upper and lower elastic members that are mounted inside the spring groove wherein the upper elastic member is disposed between an upper end of the spring groove and the supporting portion and the lower elastic member is disposed between a lower end of the spring groove and the supporting portion to support the supporting portion of the spool member upwards and downwards respectively along the piston rod; and an amplitude sensitive valve that is integrally mounted on an outer surface of the spool member to generate a damping force when the spool member is moving.