Today in 1967, US Patent 3302660 A was issued, an invention of Baron F. Haag, for his “Tapping Valve For Beer Keg.” There’s no Abstract, although in the description it includes this summary:

This invention relates to an improved valve. More specifically, it relates to an improved valve for tapping beer kegs. Still more specifically, this application relates to the special design of seal or gasket effective in valves of this type.