Patent ID: 7942145

Claim:
A rechargeable food heating system comprising: a food container, said food container including an opening for receiving a rechargeable heating element; and, a rechargeable heating element insertable into said food container, said heating element including a supersaturated salt solution contained within said rechargeable heating element; and a trigger in fluid contact with said supersaturated salt solution, said trigger comprising: an impermeable flexible membrane disposed within a surrounding rigid plug flange; a first trigger element holder having a first side attached to the inside of said flexible membrane and second side retaining a first trigger element, said first trigger element consisting of a ceramic ball, said first trigger element holder movable with said flexible membrane; and, a second trigger element holder comprising a rigid bridge portion connected at opposing ends to and spanning said plug flange and a trigger face, said trigger face rigidly retaining a second trigger element spaced apart from and directly facing said first trigger element, said second trigger element consisting of a ceramic ball; such that when said flexible membrane is pressed said first trigger element contacts said second trigger element, thereby causing nucleation within said supersaturated salt solution and triggering crystallization of said supersaturated salt solution.