Abstract: A refrigerant expansion device for a refrigeration cycle comprises a housing, a passage formed penetrating the housing, an expansion means for expanding the refrigerant passing through the passage and a flow rate control means for bypassing some of the refrigerant passing through the expansion means according to the pressure of the refrigerant, for supplying to the low pressure portion of the passage, and for controlling the flow rate of the refrigerant through the expansion means.

Abstract: An air conditioner system includes internal and external heat exchangers and a compressor for refrigerant. During cooling and heating operations, one of the heat exchangers discharges a first flow of gaseous refrigerant which is to be conducted to the compressor inlet. In order to evaporate any residual liquid refrigerant in the first flow, the first flow is passed through an evaporator in heat exchange relationship with a second flow of refrigerant discharged from the other heat exchanger. The evaporator is connected by valved conduits to receive the second flow from either the indoor or outdoor heat exchanger, depending upon whether the system is in a heating mode or a cooling mode. Within the evaporator, an upper chamber which receives the first flow is recessed into a lower chamber which receives the second flow and contains a heat transfer structure for promoting an efficient heat exchange.

Abstract: In a dual-purpose cooling/heating air conditioner, refrigerant is conducted from an evaporator to an accumulator and then into a compressor. The accumulator includes an electric heater for heating the refrigerant to a desired minimum superheat level in order to promote the evaporation of liquid refrigerant.

Abstract: An air conditioning system circulates a mixture of refrigerant fluid and lubricating oil. An accumulator is disposed upstream of a compressor to separate gaseous refrigerant from liquid refrigerant and oil. The accumulator includes an outer case, an inner case, an upstanding pipe, and a baffle plate disposed in the outer case and above the inner case. Gaseous refrigerant exits the accumulator through the pipe. Oil and possibly liquid refrigerant collect in the inner case around the pipe. Liquid refrigerant and possibly oil collect outside of the inner case. Each of the pipe and inner case include vertically spaced oil-return holes.