Hydraulic cylinder e.g. lifting cylinder, for e.g. industrial truck, has spiral groove serving as throttle element of damping device for throttling discharge of medium from one of chamber areas to end area of driving-out movement area

摘要

The cylinder has a cylinder tube (12), and a piston-piston rod-unit (18) comprising a piston rod and a piston (20). The piston divides a cylinder chamber (22) into two cylinder chamber areas (22a, 22b). A spiral groove (26) is formed in inner circumference of a piston rod guide (14) for receiving hydraulic medium. The spiral groove serves as a throttle element of a damping device for throttling discharge of hydraulic medium from one of the chamber areas to an end area of a driving-out movement area for achieving driving-out damping in the cylinder. An independent claim is also included for a method for re-tooling a hydraulic cylinder.