Bidirectional meterd flow control device

A reversible vapor compression air conditioning system having a compressor, a first heat exchanger and a second heat exchanger being selectively connected to the compressor, switching means for selectively connecting the inlet and discharge side of the compressor between the exchanger and a refrigerant supply line for delivering refrigerant from one exchanger to the other, comprising:

• a flow control device mounted in the supply line between each exchanger having an elongated body having a first end wall and a second end wall defining an internal chamber therebetween;
• the first end wall having a metering orifice axially extending therein and in communication with the internal chamber and further having a bypass opening axially extending therein and in communication with the internal chamber;
• the second end wall having a metering orifice axially extending therein, in communication with the internal chamber and in axial alignment with the metering orifice of the first end wall and further having a bypass opening axially extending radially outward from the metering orifice and in communication with the internal chamber;
• a foreshortened piston disposed in the internal chamber and being slidably movable axially in response to fluid flow, the piston having a first end face parallel to the first end wall and a second end face parallel to the second end wall, and further having a passageway extending therethrough and in axial alignment with the metering orifice of each end wall;
• whereby the piston closes off the bypass opening and establishes communication through the metering orifice in the direction of the fluid flow and permits the fluid to flow into the supply line.