Today in 1976, US Patent 3933282 A was issued, an invention of Frederick F. Stevens, Jr., and assigned to Hoff-Stevens, Inc., for his “Universal Tavern Unit for Keg Tapping Device.” Here’s the Abstract:

A universal tavern unit for a keg tapping device comprises a basic tavern unit for connection to a keg unit permanently or semi-permanently connected to a keg. The basic tavern unit is adapted to cooperate with the keg unit to provide inlet and outlet passageways which communicate with the interior of the keg for the introduction of gas under pressure into the keg and the discharge of beer or other liquid therefrom. The universal tavern unit further includes a pressure relief check valve adaptor assembly for connection to the basic tavern unit to adapt it to the requirements of an associated beer or liquid distribution system.