Thermostat control valve

Claim 1

IN COMBINATION: A SOURCE OF LIQUEFIED GAS; A VAPORIZER RECEIVING LIQUEFIED GAS FROM SAID SOURCE; A CARBURETOR RECEIVING VAPORIZED GAS FROM SAID VAPORIZER; A HEAT EXCHANGER IN OPERATIVE RELATIONSHIP WITH SAID VAPORIZER SO AS TO SUPPLY HEAT THERETO; A SOURCE OF HEATED FLUID SUPPLYING SAID FLUID TO THE HEAT EXCHANGER; AND A THERMOSTAT CONTROL VALVE CONTROLLING THE DISCHARGE OF FLUID FROM THE HEAT EXCHANGER, SAID THERMOSTAT CONTROL VALVE COMPRISING: A BODY HAVING AN INTERNAL CHAMBER AND AN INLET PORT AND AN OUTLET PORT OPENING INTO SAID CHAMBER; A VALVE PORT IN THE CHAMBER BETWEEN THE INLET AND OUTLET PORTS; A VALVE ELEMENT IN SAID CHAMBER, SAID VALVE ELEMENT HAVING AN AXIS OF MOTION, AND BEING AXIALLY MOVABLE RELATIVE TO THE VALVE PORT SO AS TO ADJUST THE FLOW RATE THERETHROUGH; A RETURN SPRING AXIALLY OPPOSED TO THE VALVE ELEMENT AND BIASING IT TOWARD A VALVE-OPEN POSITION; AND A TEMPERATURE-RESPONSIVE AXIAL-FORCE ACTUATOR OPPOSED BETWEEN THE BODY AND THE VALVE ELEMENT ON THE OPPOSITE SIDE OF THE VALVE ELEMENT FROM THE RETURN SPRING, THE INLET PORT AND THE ACTUATOR BEING IN FLUID COMMUNICATION WITH EACH OTHER, INCREASING TEMPERATURE CAUSING EXPANSION OF SAID ACTUATOR TO MOVE THE VALVE ELEMENT AGAINST THE RETURN SPRING, THEREBY TO CAUSE THE VALVE MEMBER TO REDUCE THE FLOW RATE THROUGH THE OUTLET PORT OVER AT LEAST A PORTION OF THE PATH OF THE VALVE ELEMENT.