Today in 1971, both US Patent 3591057 A and US Patent 3591058 A was issued, both inventions of Mack S. Johnston, assigned to the Republic Corp., for his “Tapping Device For Beer Kegs and the Like.” There’s no Abstract, although in the description for the first one it includes this summary:

The present device comprises a keg tapping unit which is connected about a Peerless type keg opening by insertion through the side filling opening of the keg.

Similarly, for the second patent there’s also no Abstract, although in the description for it includes this summary:

The present invention relates to a new, improved tapping device for drawing fluid such as beer from containers such as beer kegs or barrels, using a gas to drive the fluid from the container. In particular, the invention relates to a new, improved tapping device usable with conventional beer kegs and comprising a subunit, called a “keg adapter, which constantly seals the keg, and a subunit, called a coupler, which is attached to the beer dispensing apparatus in a restaurant or tavern and is readily connected to the keg adapter so that the tapping device is automatically in operating condition.