GB1461545A - Air conditioning system - Google Patents

Abstract

1461545 Refrigeration FORD MOTOR CO Ltd 23 May 1975 [10 June 1974] 22611/75 Heading F4H In an air conditioning system for a vehicle, comprising a compression-condensation refrigeration circuit, a thermal expansion valve in the circuit has a calibrated fixed flow passage in parallel with a variable flow orifice whereby a small amount of refrigerant flows through the valve when the variable orifice is closed, the variable flow orifice of the thermal expansion valve being controlled by both the refrigerant pressure immediately downstream of the expansion valve and the refrigerant temperature intermediate the evaporator and a suction throttling device 18. As shown, Fig. 2, the thermal expansion valve comprises inlet and outlet ports 22, 23 connected by an opening 24 controlled by a ball valve 26 which is coupled by stems 32 to a diaphragm 30, a chamber above the diaphragm being connected by a passage 34 to a thermal bulb 31 in thermal communication with a point 4 between the evaporator and the suction throttling valve, and the chamber below the diaphragm communicates with the outlet 23 by means of the clearance between the stems 32 and the passages 25 therefor. The valve also includes a by-pass orifice 36 in parallel with the valvecontrolled opening 24.