| 摘要 |
A hydraulic cylinder is provided to simplify a structure thereof by assembling a piston nut and a cushion ring through a plurality of fixing units and a set screw. A hydraulic cylinder(10) includes a hollow cylinder(12), a head cover(14), a rod(20), a piston(16), a piston nut(30), and a cushion ring(40). The head cover has a male screw unit on an outer periphery of one end and reciprocates in a longitudinal direction of the cylinder. The piston is coupled with the male screw unit of the rod to move with the rod during reciprocation of the rod. The piston nut is coupled with the male screw unit of the rod and in contact with the piston to prevent the piston from being separated from the rod. One end of the cushion ring is arranged between an outer peripheral surface of the rod and an inner peripheral surface of the piston nut, and the other end thereof is protruded from the piston nut so as to generate buffering pressure for preventing sudden collision between the piston nut and the head cover when the piston moves to the head cover. The hydraulic cylinder further includes a fixing device to fix the cushion ring and the piston nut to each other. The fixing device includes a first fitting groove formed on the inner peripheral surface of the piston nut, a second fitting groove formed on an outer peripheral surface of the cushion ring, a plurality of fixing units(45) received in the first and second fitting grooves to be arranged along an outer periphery of the cushion ring, and a set screw(50) passing through the first fitting groove and an outer peripheral surface of the piston nut to be in contact with one of the fixing units. |
