Closure for hot beverage container

Claim 1

A closure having anti-evaporation and spill-resistant features for use on a multi-serving capacity container for hot beverages, said closure incorporating therein a filling passageway formation through which hot beverage can be introduced into said container while said closure occupies its closing position thereon; said filling passageway formation comprising conduit means providing a filling passageway through said closure and having an outer foraminous opening at one end lying in the exposed outer surface of said closure through which hot beverage may be poured and an inner foraminous opening at the opposite end of said passageway lying in the exposed inner surface of said closure, said passageway having an apertured baffle positioned intermediate said outer and inner openings; a relatively light-weight floatable ball trapped with freedom to move in an axial direction in said passageway between said outer opening and one side of said baffle; a relatively heavy-weight ball trapped with freedom to move in an axial direction in said passageway between said inner opening and the opposite side of said baffle; said relatively light-weight floatable ball automatically assuming a seated position on said baffle closing the aperture therein when a container closed by said closure is in its upright position and lifting from said seated position and opening said aperture to relieve excess pressure in said container; and said relatively heavy-weight ball normally resting in a non-passageway-closing position when a container closed by said closure is in its upright position and automatically assuming a seated position against said baffle closing said aperture therein when said container is overturned thereby preventing the contents of said container gushing therefrom.