Patent attributes
There is provided an expansion valve which, by moving the sub-valve in a valve housing, controls the flow rate of a refrigerant in a first flow direction and releases the refrigerant to flow in a second flow direction, wherein the sub-valve is reduced in weight and a valve port is provided with high accuracy. The sub-valve includes a guide member formed by press work and a valve seat member formed by cutting. The sub-valve is seated on a sub-valve seat of a valve seat ring when the pressure in a main valve chamber is high, and is moved away from the sub-valve seat when the pressure in the main valve chamber is low. The sub-valve is reduced in weight by forming the guide member by press work, and the valve port is formed with improved accuracy by forming the valve seat member by cutting.