Air conditioning system employing non-condensing gas with accumulator for pressurization and storage of gas

摘要

An air conditioning system for an enclosed space employing a unitary compressor and expander of the positive displacement type, each having an inlet port and an outlet port, with a primary heat exchanger connected between the compressor outlet port and the expander inlet port and a secondary heat exchanger connected between the expander outlet port and the compressor inlet port to complete a closed loop having a charge of gas, the gas being non-condensing at the temperatures and pressures encountered in the unit. An accumulator holds an auxiliary charge of the pressurized gas at a pressure which is lower than the pressure existing in the primary heat exchanger and higher than the pressure existing in the secondary heat exchanger. A first intermittently operated valve couples the accumulator to the secondary heat exchanger for injection of auxiliary gas into the closed loop to raise the pressure in the secondary heat exchanger substantially above the atmospheric level to increase the heat rate of the system. A second intermittently operated valve couples the accumulator to the primary heat exchanger so that air is bled from the primary heat exchanger to decrease the heat rate of the system. The valves have a common operator arranged to operate the valves alternatively. It is one of the distinctive characteristics of the present invention that the loop is free of any intentional restriction in the form of a capillary or the like, or any change of phase, so that the system may be switched between high and low heat rates without risk of the "slugging" or "starvation" encountered in conventional air conditioning systems.