Abstract: A refrigerant flow-control valve operable between a no-flow condition and a flow condition in response to a control signal supplied thereto. The flow-control valve includes a tubular-shaped body forming a refrigerant passageway extending from an inlet to an outlet, a cylindrically-shaped restrictor secured within the tube and forming a restriction, and a cylindrically-shaped stop secured within the tube and forming a plunger valve flow passage. The stop is located downstream and spaced-apart from the restrictor and the restriction has a greater resistance to flow than the valve flow passage. A plunger is within the tube between the restrictor and the stop and carries a valve element. The plunger is movable between a first position closing the valve flow passage to generally prevent refrigerant flow therethrough and through the passageway and a second position opening the valve flow passage to permit refrigerant flow therethrough and through the passageway.

Abstract: A refrigerant flow-control valve is operable between a mid-flow condition, a low-flow condition, and a high-flow condition in response to an electronic control signal supplied thereto and a pressure drop across the valve. The valve includes a tubular-shaped body having an inlet and an outlet and forming a refrigerant passageway extending from the inlet to the outlet, a cylindrically-shaped restrictor secured within the tube and forming a first restriction, a cylindrically shaped end stop secured within the tube and spaced-apart from the restrictor, and a plunger within the tube between the restrictor and the end stop. The plunger forms a first valve-element flow passage between its outer periphery and the tube and carries a first valve element which movable between a first position closing the first valve-element flow passage and a second position opening the first valve-element flow passage. The second restriction has a greater resistance to refrigerant flow than the first restriction.

Abstract: An electronic variable orifice tube suitable for use as an expansion valve in a refrigeration system providing two flow rates in response to electronic control signals comprises a bodytube, a restrictor mounted within the bodytube and defining a first flowpath. A plunger is translatably positioned within the bodytube in proximity to the restrictor and defines a second and a third flowpath. A valve actuator is functionally coupled to the plunger to translate the plunger within the bodytube to transition between the two flow rates. A high flowpath is formed through the bodytube by the first, second, and third flowpaths, and a low flowpath is formed through the bodytube by the first and the second flowpaths to the exclusion of the third flowpath. A solenoid may be used as the valve actuator and a spring may be employed to return the plunger to its quiescent state when the solenoid is not energized.