A blocking device for mounting within a space defined within a hollow structure includes a holder and an expandable member. The holder is adapted to be mounted within the space. The expandable member is supported on the holder and is expandable by heat to form a foam member in order to block or substantially...http://www.google.fr/patents/US7422088?utm_source=gb-gplus-shareBrevet US7422088 - Blocking devices for hollow structures
