Throttle valve for the expansion of the coolant in the coolant circuit of the barrel of a motor vehicle - air conditioning system

摘要

A multiple stage expansion valve for use in an air conditioning system for an automotive vehicle including multiple stage flow control orifices located between a refrigerant condenser and a refrigerant evaporator, the high pressure side of the refrigerant gas compressor being in fluid communication with the inlet side of the condenser, the low pressure side of the compressor being connected to the outlet side of the evaporator through a suction throttling valve device, said expansion device comprising multiple stage orifice valves defined in part by a movable piston that responds to the pressure differential across the expansion device to establish optimum refrigerant flow through the air conditioning system during operation at high load, for establishing a relatively high fluid flow restriction during operation at low and moderate loads, and for establishing a moderate fluid flow restriction during operation at high loads and low compressor speeds.