Today in 1934, US Patent 1951996 A was issued, an invention of Josef Schaefer, for his “Brewing Pan.” There’s no Abstract, though it’s described this way in the application:
My invention relates to improvements in brewing pans, and more particularly in the construction of the rotary liquid heater. One of the objects of the improvements is to provide a liquid heater which is simple in construction, and in which the water of condensation is readily removed from the heating coil. With this object in view my invention consists in providing the liquid heater with a single heating pipe wound into a coil having several superposed windings, each winding being preferably substantially in the form of a star. By constructing the coil from a single pipe only two openings are needed in the supply one for admitting the steam and the other for removing the water of condensation.