| 摘要 |
PURPOSE:To make a seal effect between a piston and a cylinder improvable, by forming each skirt in both first and second plastic bands, while making these skirts stick fast to the cylinder in processes at both expanding and contracting sides. CONSTITUTION:Throttling folds of a first skirt 26a and a second skirt 34a elastically stick fast to a cylinder 1 in an assembled state, and with an increase of pressure in an A chamber 4 in time of stretching processes, the skirt 34a receives oil pressure and is deformed to the side of the cylinder 1, yet more sticking fast to the cylinder 1, thus aleak is prevented from occurring. In time of contracting processes, with an increase of pressure in a B chamber 5, the first skirt 26a is deformed to the side of the cylinder 1 and sticks fast to it, preventing a leak from occurring, thus sealability is improved. |
