VARIABLE DAMPING FORCE SHOCK ABSORBER WITH VARIABLE ORIFICE FOR ADJUSTING DAMPING CHARACTERISTICS

摘要

A variable damping force shock absorber has a hollow cylinder, in which is disposed a thrusting piston for defining upper and lower fluid chambers. A fluid path is defined through the piston and a piston rod for establishing fluid communication between the upper and lowr fluid chambers. A first flow restrictive orifice is provided in the fluid path which first flow restrictive orifice is variable of flow restriction characteristics according to a first variation characteristics in relation to a piston stroke speed. A second flow restrictive orifice is also provided in the fluid path. The second flow restrictive orifice is variable of magnitude of flow restriction according to a second variation characteristics in relation to the piston stroke speed, which second variation characteristics is so determined as to establish linear variation of damping force in relation to the piston stroke speed. A communication path is formed for establishing communication between the first and second flow restrictive orifices. The communication path has a first section extending radially and a second section extending axially and defined between the piston rod and the piston.