Patent ID: 8671677
Filing Date: 2014-03-18
Classification: F02G

Abstract:
1. An improved free piston Stirling machine having a gamma configuration and including a displacer having an inner end and reciprocatable within a displacer cylinder along a displacer axis and separating a workspace into a compression space and an expansion space, the improvement comprising: (a) at least two power pistons, the pistons arranged in a balanced configuration for canceling their momentum vectors, each piston having an inner end and being reciprocatable within a piston cylinder having an inner end, each piston cylinder having an unobstructed opening at the respective inner end into a common volume of the workspace, the common volume being defined by intersection of inward projections extending from each of the displacer cylinder and the piston cylinders, such that the displacer and the pistons each have a range of reciprocation extending into the common volume; and (b) a displacer drive rod reciprocatable in a drive rod cylinder, the displacer drive rod and the drive rod cylinder positioned outside the common volume and on the opposite side of the common volume from the displacer, the displacer being connected to the displacer drive rod by a displacer connecting rod.