Hydraulic cylinder

Abstract

An object of the present invention is to provide a hydraulic cylinder enabling a reduction in a stress generated by the pressure of hydraulic fluid at a welded portion of a case containing a damping valve. A piston (5) coupled with a piston rod (6) is slidably inserted in a cylinder (2, 3) sealingly containing hydraulic fluid. A joint (17) is attached to the side wall of an outer cylinder (3) of the cylinder. A damping force is generated by controlling a flow of the hydraulic fluid caused by a sliding movement of the piston in the cylinder by a damping force generating mechanism (19) contained in the joint (17). A valve case (18) of the joint (17) has a reduced diameter at a connection portion (23) welded to the outer cylinder (3). The reduced diameter is smaller than the diameter of the damping force generating mechanism (19) contained in the valve case (18). The reduction in the diameter of the connection portion (23) which is a welded portion results in a reduction in a stress generated at the connection portion (23) by the pressure of the hydraulic fluid, whereby the strength against the pressure applied to the welded portion can be increased.

Dependencies are inferred from the claim text.