Today in 1947, US Patent 2430774 A was issued, an invention of Frederick E. Lynn, for his “Liquid Cooler.” There’s no Abstract, although in the description it includes these claims:

My invention relates more particularly to a beverage serving system and apparatus, and especially to means for cooling or chilling beverages such as beer during flow thereof from a container can be maintained in service while ‘other faucets or pipes supplying the same are being replaced or repaired.

A further object of my invention is to provide an arrangement wherein danger of leakage of refrigerant liquid into the beverage pipes or leakage from the beverage pipes into the refrigerant conduit or expansion chamber is minimized, without substantial detraction from the effectiveness of the heat transfer as between the beverage pipes and the refrigerant.

Still another object of my invention is to provide a refrigerating or cooling system that can conveniently be expanded to care for more than one group of dispensing faucets.