| 摘要 |
<p>Method and apparatus for improving the superheat control of a thermostatic expansion valve metering refrigerant into a refrigeration system evaporator coil is disclosed in one exemplar embodiment having a superheat setting means (48) for establishing a required superheat, superheat determination means for measuring the superheat of the valve across the evaporator coil (32 and 34), differential means for comparing the measured superheat with the established superheat (56 or 66), and heating means (40) cooperating with the differential means for applying heat to the fluid-charged bulb of the valve when the measured superheat exceeds the established superheat. A heating control means (38) may also be included to control the heating means for increasing the rate of heating by the heating means when the measured superheat exceeds the required superheat, and for decreasing the rate of heating by the heating means when the required superheat exceeds the measured superheat.</p> |
