This Personal Floatation Device concept is a solution seeking to use forces already at work upon the jacket to inflate itself. This was a submission to the Innovations in Life Jacket Design competition sponsored by BoatUS. The idea is to eliminate the bulk of the foam that gets in the way when you are not in the water, yet give adequate bouyancy when it is needed. The solutions that enable this are: 1) Using bouyancy to create vacuum 2) Front and Rear Expansion Pockets 3) Air Flow Valve. As illustrated below, the jacket starts out slim and expands into a very bouyant device. Upon submersion, the foam-padded flaps on the chest and back want to rise to the surface. This force is harnesed and put to work. To reach the surface, these hinged flaps must inflate to an air-tight expansion chamber, as an accordian is filled by pulling the ends apart.
