Free piston Stirling engine

Abstract

A free piston Stirling engine includes a displacer fitted in a cylinder so as to be able to reciprocate and defining an expansion chamber and a compression chamber in the cylinder, an operational sealing area leading from the expansion chamber to the compression chamber and interposed a heater, a regenerator and a cooler in order, a free piston disposed so as to be able to reciprocate toward a direction which crosses a direction of the reciprocation of the displacer and defining an operational chamber which is communicated with the compression chamber and a buffer chamber at its both ends and a linear generator disposed around the free piston and connected with a storage battery at its output terminal via an AC/DC converter having one or more transformation ratios. According to this constitution, even though the load is larger than the output of the linear generator transitionary, it is possible to supply stable electric power by use of the storage battery. In the opposite direction, it is possible to store the surplus energy in the storage battery when the load is smaller than the output of the linear generator. Accordingly, even though the output of the free piston Stirling engine is under the unbalance condition with regard to the load quantity, especially when the load quantity is larger than the output of the free piston Stirling engine, the free piston Stirling engine can be stably operated.

Dependencies are inferred from the claim text.