HYDRAULIC CYLINDER

摘要

A hydraulic cylinder provided with: a piston for defining within a cylinder tube a driving pressure chamber and a cushion pressure chamber; an air chamber defined within a hollow piston rod; an orifice for guiding to the air chamber an operating liquid in the cushion pressure chamber which contracts in an extension operation; and a check valve for returning the operating liquid in the air chamber to the driving pressure chamber as the pressure difference between the air chamber and the driving pressure chamber rises to a level higher than or equal to a predetermined value. The piston rod is provided with a cylindrical hollow rod and a rod end cap which closes the upper opening end of the hollow rod, and the air chamber is defined between the hollow rod and the rod end cap.