Valve structure of shock absorber

摘要

Provided is a valve structure of a shock absorber which is capable of controlling respective damping forces according to a frequency in compression and rebound motions of a piston valve, thereby satisfying both the ride comfort and the control stability. The valve structure of the shock absorber, which has a cylinder filled with a working fluid and a piston rod having one end located inside the cylinder and the other end extending outward from the cylinder, includes: a main piston valve assembly installed at one end of the piston rod and configured to operate in a state that the inside of the cylinder is divided into an upper chamber and a lower chamber, and generate a damping force varying according to a moving speed; and a frequency unit configured to move together with the main piston valve assembly and generate a damping force varying according to a frequency. The frequency unit includes: a hollow housing mounted at a lower end of the piston rod such that the housing is disposed under the main piston valve assembly; and a free piston disposed to be vertically movable within the housing.

主权项

1. A valve structure of a shock absorber including a cylinder filled with a working fluid and a piston rod having one end located inside the cylinder and the other end extending outward from the cylinder, the valve structure comprising:
a main piston valve assembly installed at one end of the piston rod and configured to operate in a state that the inside of the cylinder is divided into an upper chamber and a lower chamber, and generate a damping force varying according to a moving speed; and a frequency unit configured to move together with the main piston valve assembly and generate a damping force varying according to a frequency, wherein the frequency unit comprises: a hollow housing mounted at a lower end of the piston rod such that the housing is disposed under the main piston valve assembly; a free piston disposed to be vertically movable within the housing; an auxiliary valve assembly mounted at a lower end of the housing; an elastic member configured to elastically support the free piston within an inner space of the housing; and a mount portion concavely formed on a bottom surface of the free piston, wherein the inner space of the housing is partitioned into an upper space and a lower space by the free piston, in which the free piston has a through-hole that is opened during a low-frequency compression to allow the working fluid to flow from the lower space to the upper space, and wherein the free piston includes a valve body that is stacked on an upper surface of the free piston in the upper space so as to move together with the free piston and maintains the through-hole in a closed state when no external force is applied.