Heat exchange system having recycling fluent material receiving and discharging heat

Claim 1

A COFFEE-MAKING MACHINE COMPRISING, A DISPENSING HEAD HAVING A VALVED OUTLET COMMUNICATING WITH THE AMBIENT, A BOILER DISPOSED SPACED FROM SAID DISPENSING HEAD FOR HEATING WATER THEREIN AND HAVING A SPACE FOR RECEIVING STEAM FROM WATER HEATED THEREIN, MEANS DEFINING A WATERFLOW PATH HAVING A PORTION EXTERNAL TO SAID BOIL FOR RECIRCULATING HEATED WATER FROM SAID BOILER THROUGH SAID DISPENSING HEAD AND BACK TO SAID BOILER, SAID HEATED WATER BEING COOLED WHILE IN SAID EXTERNAL PORTION OF SAID FLOW PATH, AND HAVING A PORTION DEFINING A HEAT EXCHANGER PORTION OF SAID FLOW PATH PASSING THROUGH SAID BOILER AT AN INCLINATION TO THE VERTICAL AND BEING PARTIALLY IMMERSED IN THE BOILER WATER FOR EXTRACTING HEAT FROM THE WATER AND STEAM IN SAID BOILER, AND SAID MEANS DEFINING SAID EXTERNAL PORTION OF SAID FLOW PATH COMPRISING A FIRST CONDUIT EXTERNAL OF SAID BOILER AND COMMUNICATING BETWEEN SAID HEAT EXCHANGER PORTION AND SAID DISPENSING HEAD FOR SUPPLYING HEATED WATER FROM SAID HEAT EXCHANGER PORTION TO SAID DISPENSING HEAD AND A RETURN CONDUIT EXTERNAL OF SAID BOILER AND COMMUNICATING BETWEEN SAID HEAT EXCHANGE PORTION AND SAID DISPENSING HEAD FOR RETURNING WATER FROM SAID DISPENSING HEAD TO SAID HEAT EXCHANGE PORTION WHEN SAID VALVED OUTLET OF SAID DISPENSING HEAD IS CLOSED, SAID RETURN CONDUIT COMMUNICATING WITH SAID HEAT EXCHANGER PORTION AT A POINT SPACED ALONG SAID FLOW PATH FROM A POINT AT WHICH SAID FIRST CONDUIT COMMUNICATES WITH SAID HEAT EXCHANGER PORTION, AND MEANS FOR SUPPLYING WATER TO SAID BOILER, WHEREBY WATER IS CIRCULATED THROUGH SAID WATER-FLOW PATH AUTOMATICALLY DUE TO CONVECTION FLOW.