Patent attributes
A valve structure includes a piston valve assembly, and a frequency unit including a hollow housing, a free piston and an auxiliary valve assembly. The piston valve assembly, installed at one end of a piston rod, operates with the inside of a cylinder being divided into upper and lower chambers, and generates a damping force varying according to a moving speed. The frequency unit moves together with the piston valve assembly and generates a damping force varying according to a frequency. The housing is mounted at a lower end of the piston rod such that the housing is disposed under the piston valve assembly. An inner space of the housing is partitioned into upper and lower spaces by the free piston. The free piston is disposed to be vertically movable within the housing. The auxiliary valve assembly is mounted at a lower end of the housing.
