| 摘要 |
<p>The invention relates to a vapor compression refrigeration system for cooling air, particularly for use in automobiles, having a closed circuit for refrigerant fluid incorporating an expansion device in the form of an orifice tube (12) supplying expanded refrigerant fluid to an evaporator (13) for cooling the air, wherein the system comprises electrical heating means such as a resistive wire winding (17) or film resistor to supply heat to the refrigerant fluid within the orifice tube, and control means (18) for controlling the heating means so as to achieve desired mass flow rates of the expanded fluid in the evaporator. The control means may operate in response to signals from a pressure sensor (19) downstream of the evaporator and from further sensors sensing the temperature and speed of the air to be cooled as it enters the evaporator. <IMAGE></p> |
