PISTON JOINT STRUCTURE OF HYDRAULIC CYLINDER

摘要

PROBLEM TO BE SOLVED: To provide a piston joint structure of a hydraulic cylinder capable of improving durability of a fixing bolt and its life. SOLUTION: A fixing bolt 21 is inserted into a screw hole 20 formed in a piston rod 3 from the first penetration hole 19 bored in a piston 5 and fastened to fix the piston 5 to the piston rod 3. A piston 5 joint structure of a hydraulic cylinder 1 of which the internal body 2 is divided into a rod side chamber 4a and a bottom side chamber 4b by the above structure, is obtained. A strut bolt 25 which is inserted in the secondary penetration hole 24 bored at the radial central part of the piston 5 and fastened to bring into contact with the side end face of the fitting part 7 of the minor diameter part 13 of the piston rod 3, is provided in order to impart a reverse bending force so as to act toward the axial counter rod side at the inner peripheral part 18b of the rod side end 18 of the piston 5 to withstand a bending force acting to the axial rod side in the inner peripheral part 18b of the rod side end 18 of the piston 5. COPYRIGHT: (C)2003,JPO