| 摘要 |
A cylinder and piston construction for a compressor or vacuum pump has a cylinder defined by co-axial cylinder and guideway sleeves. The guideway sleeve is larger in diameter than the cylinder sleeve and the cylinder sleeve extends axially into the guideway sleeve. A piston has a cylindrical base which is guided via skirt bearings in the guideway and a head which extends from the base into the compression chamber defined by the cylinder sleeve and has a piston ring which forms a sliding seal with the cylinder sleeve. An annular cavity is defined between the piston head and the piston base into which the cylinder sleeve extends so that the top skirt bearing is positioned closer to the top of the piston head and further away from the bottom skirt bearing so as to steadily guide the piston head in the cylinder sleeve, thereby reducing wear and increasing the life of the pump. |
