FREE-PISTON STIRLING MACHINE IN AN OPPOSED PISTON GAMMA CONFIGURATION HAVING IMPROVED STABILITY, EFFICIENCY AND CONTROL

摘要

An opposed piston gamma type Stirling machine has its displacer driven by a linear electromagnetic transducer that is drivingly linked to the displacer and is located on the opposite side of the power piston's axis of reciprocation from the displacer preferably in the bounce space. The linear transducer is controlled by an electronic control as a function of sensed inputs of Stirling machine operating parameters. In addition to allowing improvements in stability and efficiency, such a Stirling machine operated as a cooler/heat pump can also be controlled so that its displacer can be driven at (1) a phase angle that pumps heat in one direction through the machine or (2) at another phase angle that pumps heat in the opposite direction through the machine and allows selectively switching between the heat pumping directions.