US Patent 7091455 Electric thermos jug

An electric thermos jug comprises generally from the top to the bottom a lid assembly, a spout assembly, a double-layer vacuum body, a heating element, an underbody, and a base. An insulating plate and an insulating material layer are provided under the heating element inside the underbody of the jug. The lid is two-layer structure comprising an upper lid and lower lid with an air plenum in between. The electric thermos is convenient for use and effective in heat insulation due to the excellent air tightness of the components. The temperature inside the jug can be maintained for a long time without the need of repetitive heating. As a result, it can maintain a good water quality and is energy efficient. A safety valve is also employed.