SEALING DEVICE FOR HYDRAULIC CYLINDERS

摘要

The invention relates to a sealing device to prevent dust and dirt from penetrating into lubricated surfaces and hydraulic oil seals of a hydraulic cylinder. The hydraulic cylinder includes a piston (11) and a cylinder (12) and a protective cover (20) that is rigidly connected with the piston rod of the piston (11). The invention is characterised in that the protective cover (20) is coaxially placed around the cylinder and is arranged to form a gap seal (21) around the mantle surface of the cylinder (12), and has an extension enabling it to essentially cover all of the cylinder (12) when the hydraulic cylinder is in its compressed condition. A ring-shaped seal (22) is placed on the cylinder (12) at the mantle surface between this and the protective cover (20), where the ring-shaped seal is brought along by the cylinder in its motion. The ring-shaped seal (22) is placed on the cylinder (12) in the vicinity of its opening for the piston rod, where the ring-shaped seal is covered by the protective cover (20) for the whole cylinder (12) stroke.