Sealing device for Stirling engine piston rod in which no separation of oil and gas is necessary

摘要

In Stirling engines the high pressure of the cycle requires special seals on the piston rod to prevent leakage of gas out of the high pressure cylinder into lower pressure regions such as a crankcase. A liquid oil seal is developed in a chamber around the piston rod by movement of the piston rod to carry oil into the chamber which is limited by an upper scraper member and a lower sealing gland. The chamber leads to a membrane operated pressure comparison valve releasing oil from the chamber when its pressure exceeds that of the gas in the high pressure cylinder. No gas need be pumped back into the high pressure chamber and thus no separation of gas and oil is necessary.