| 摘要 |
PURPOSE:To secure such a nonlubricating seal structure that lowers the extent of surface pressure acting on a piston ring, reduces an abrasive loss and makes service life improvable, by forming each ring land of the piston ring and a piston into a sectional T form. CONSTITUTION:A T-type piston ring 5 is pressed to a cylinder liner 1 by means of a pressure differential between both upper and lower spaces of a piston 6, and thereby it prevents any gas leakage due to vertical motion of the piston 6. Now, pressing force of the T-type piston ring 5 pressing the cylinder liner 1 depends on pressure receiving thickness b1 on the backside of the piston ring 5 by the vertical pressure differential of the piston 6. That is to say, since the back pressure receiving thickness b1 of the T-type piston ring is less than contact thickness b0 between the cylinder liner 1 and the T-type piston ring, the pressing force to the cylinder liner is also decreased, corresponding to that. Therefore, an abrasive loss is reduced and its service life is improvable. |
