Today in 1960, US Patent 2936236 A was issued, an invention of Robert C. Gadsby, Schwaiger Joseph, and Frank H. Schwaiger, assigned to Anheuser Busch, for their “Method of Draining Off Wort From a Straining Tank.” There’s no Abstract, but the description states that the “invention relates to a straining tank or grain extractor or lauter tub, and more particularly to a new type of straining tank for use in the brewing industry to remove extract from brewers grains. This divisional application relates to the method of straining employed by said straining tank.”
These were used by AB and called a Strainmaster. These were faster than the Lauter tuns of the day but have all been replaced. Today’s Lauter tuns offer better clarity, efficiency, and speed hence the Strainmaster is not used any more.