Patent ID: 6082119
Filing Date: 2000-07-04
Classification: F25B

Abstract:
A Joule-Thomson refrigeration system wherein a compresses refrigerant fluid is expanded to effect cooling, said system comprising:a cryostat;said cryostat comprising an expansion valve located at the cold downstream end of said cryostat;said expansion valve having a valve core and a cooperating valve seat;a commandable actuator located at the warm upstream end of said cryostat;said actuator being coupled to said valve core such that when said actuator is energized said valve core withdraws from said valve seat to a more open position, and when said actuator is deenergized or reversed said valve core returns to its normal operating position; wherebywhen said valve core is withdrawn to its more open position, any contaminants that have accumulated in said expansion valve are dislodged and flushed from said expansion valve by the increased flow of refrigerant and when said valve core of said expansion valve is returned to its normal operating position, normal expansion of said system resumes;said actuator providing a means by which said expansion valve can be commandably controlled to clear contaminants from it, increase flow to accelerate cooldown, and modulate flow to regulate the amount of refrigeration produced.