Ultra-low vibration split Stirling linear cryogenic cooler with a dynamically counterbalanced pneumatically driven expander

The paper deals with the theoretical study and practical implementation of a novel approach to a passive dynamic counterbalancing the pneumatically driven expander of a split Stirling cryogenic cooler. The objective is achieved by using a “spring-mass-spring” counterbalancer placed inside the spring chamber of the cold finger between the hot side of the movable displacer-regenerator and the stationary casing. The counterbalancer mass and springs rates are optimized so as to produce full cancellation of the fundamental component of the vibration export without affecting the overall cooling performance. The full-scale experimentation supports strongly the results of theoretical predictions.