A soda machine was a type of vending machine that dispensed a selection of sodas in containers.
In 1957, Johnnies Market in Carbon Creek had a wheeled soda machine on its front porch which sold Pepsi-Cola. (ENT: "Carbon Creek")
The Griffith Observatory also had a soda machine. In 1996, Rain Robinson directed a supposedly lost Tuvok and Tom Paris past the machine towards the building's lobby. (VOY: "Future's End")