HYDRAULIC DAMPER

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic damper capable of securely showing the damping force to the external force having a very small amplitude. SOLUTION: This hydraulic damper is provided with an O-ring 27 at an inner diameter side of a seal groove 35 formed in the periphery of a piston 38, and provided with a piston seal member 29 in an outer diameter side thereof to prevent a leak of the oil of oil pressure chambers 20 and 21 provided in both sides of the piston 38 inside of a hydraulic cylinder 16 from a clearance between the inner peripheral surface in the axial direction of the hydraulic cylinder 16 and the peripheral part of the piston 38. A step part 31 is formed in the seal groove 35 in each side surface so that the outer diameter side width W1 is larger than the inner diameter side width W2 of the seal groove 35, and the piston seal member 29 is tightly fitted to the step parts 31 at the inner diameter side thereof.