近年来美国的各种制冷机都取得了重大的发展。着重讨论了在布雷顿、焦耳一汤姆逊、斯特林、脉管以及磁制冷机方面的一些进展。可靠性已成为新的研究领域的主要推动力。回顾了近几年在改进制冷机可靠性方面的一些探讨,比较了不同循环的优点和弊端,还讨论了每种制冷机的最新改进。 In recent years, various refrigerators in the United States have made significant progress. Some of the developments in Breton, Joule-Thomson, Stirling, Vascular and Magnetic Chillers are highlighted. Reliability has become a major driver of new research areas. In the last few years, some discussions on improving the reliability of chillers are reviewed. The advantages and disadvantages of different cycles are compared. The latest improvements of each chiller are also discussed.