| 摘要 |
The compressor contains at least one piston (5) guided in a dry-running manner which, together with a cylinder insert (33), bounds a ring gap which is open over the common longitudinal section in each case and permits a leakage flow of the compressed medium. The piston (5) is coupled via a piston rod (42) to a support part (38) which is displaceably guided in the direction of its longitudinal axis (6) and is connected to a drive device. The piston rod (42) cooperates with the piston (5) and the support part (38) via support surfaces (43) which are convex at the end faces and permit relative movements of the support part (38) with respect to the piston (5) which extend transversely to the longitudinal axis (6). Accordingly, a parallel guidance of the piston (5) in the cylinder insert (33) is achieved which is not influenced by oscillations of the driving parts. The piston (5) has a metallic basic body (61) and a sleeve member (62) made of a plastic material on which the running surface of the piston (5) is formed. The cylinder is manufactured of a material whose coefficient of thermal expansion corresponds at least approximately to a resultant coefficient of thermal expansion of the materials of the basic body (61) and of the sleeve member (62). The compressor in accordance with the invention is particularly suitable for the oil-free compression of a gas. |
