Patent ID: 7784300
Filing Date: 2010-08-31
Classification: F01C,F04B,F25B,Y02E

Abstract:
1. A refrigerator comprising: at least a piston and cylinder assembly including a piston reciprocatingly mounted within a cylinder space, at least an intake port and a discharge port, and at least two cooling chambers being integrally formed in a cylinder head, each said cooling chamber having a heat exchanger unit disposed therewithin, a port leading to said cylinder space and at least a cooling-chamber valve, said valve opening or closing said port to establish or block the flow of a gaseous working fluid between each said cooling chamber and cylinder space, wherein each said cooling chamber is adapted to operate on an associated cycle comprising a compression stroke wherein an amount of working fluid is compressed into each said cooling chamber, an expansion stroke wherein working fluid in each said cooling chamber expands into the cylinder space to return an amount of work to the piston and produce an amount of cooled working fluid, and before the expansion stroke a time period for heat transfer from the working fluid enclosed within said cooling chamber to a heat sink to reduce a temperature of the enclosed working fluid; wherein during said time period when said working fluid is enclosed within each said cooling chamber, said piston provides strokes for the working fluid associated with another cooling chamber.