Films with stress relief intra-chamber seals

Abstract

The present disclosure relates to an inflatable cushion including a first film ply and a second film ply that is sealed to the first ply. The first and second plies can define an inflation chamber therebetween that can be inflatable with a fluid and operable to contain the fluid. An interior seal can be disposed within the inflation chamber attaching the first and second plies together. The interior seal can include a perimeter seal that encloses an inner portion in which the first and second plies are unattached from one another.

What is claimed is: 
     
         1 . An inflatable flexible structure, comprising:
 a first film ply;   a second film ply that is sealed to the first ply to define an inflation chamber therebetween that is inflatable with a fluid and operable to contain the fluid; and   an interior seal disposed within the inflation chamber attaching the first and second plies together, the interior seal including a perimeter seal that encloses an inner portion in which the first and second plies are unattached from one another.   
     
     
         2 . The inflatable flexible structure of  claim 1 , wherein the perimeter seal entirely encloses the inner portion, separating the inner portion from the inflation chamber. 
     
     
         3 . The inflatable flexible structure of  claim 1 , wherein the interior seal is disposed within the inflation chamber. 
     
     
         4 . The inflatable flexible structure of  claim 3 , wherein the interior seal is disposed entirely within the inflation chamber. 
     
     
         5 . The inflatable flexible structure of  claim 1 , wherein the interior seal includes a first elongated portion extending from the perimeter seal. 
     
     
         6 . The inflatable flexible structure of  claim 5 , wherein the interior seal includes another perimeter seal, and wherein the first elongated portion extends from the perimeter seal to the other perimeter seal. 
     
     
         7 . The inflatable flexible structure of  claim 5 , wherein the interior seal includes an intersection between the perimeter seal and the elongated portion, such that the intersection has three leg portions which are part of the perimeter seal and the elongated portion, the interior seal having an increased width at the intersection compared to the perimeter seal and elongated portion, thereby forming a gusset that resists localized stresses in the sealed film plies. 
     
     
         8 . The inflatable flexible structure of  claim 7 , wherein the interior seal includes a second intersection between the perimeter seal and a second elongated portion, such that the second intersection has three second leg portions which are part of the perimeter seal and the second elongated portion, the interior seal having an increased width at the second intersection compared to the perimeter seal and second elongated portion, thereby forming a second gusset that resists localized stresses in the sealed film plies. 
     
     
         9 . The inflatable flexible structure of  claim 8 , wherein the first elongated portion extends from the perimeter seal to a second perimeter seal, and wherein the second elongated portion extends from the perimeter seal to a third perimeter seal. 
     
     
         10 . The inflatable flexible structure of  claim 5 , wherein the inner portion is at least 10 times wider than the elongated portion. 
     
     
         11 . The inflatable flexible structure of  claim 1 , comprising a plurality of said interior seals. 
     
     
         12 . The inflatable flexible structure of  claim 1 , wherein the first and second plies are sealed to one another to define a plurality of inflation chambers therebetween, the plurality of inflation chambers including the inflation chamber and a second inflation chamber. 
     
     
         13 . The inflatable flexible structure of  claim 12 , wherein the second inflation chamber includes a second interior seal attaching the first and second plies together, the second interior seal including a second perimeter seal that encloses a second inner portion in which the first and second plies are unattached from one another. 
     
     
         14 . The inflatable flexible structure of  claim 1 , wherein the inner portion is configured to remain uninflated when the inflation chamber is inflated with the fluid. 
     
     
         15 . The inflatable flexible structure of  claim 1 , wherein the first and second plies are heat sealed together to form the interior seal. 
     
     
         16 . The inflatable flexible structure of  claim 1 , wherein the first and second plies are sealed together with an adhesive to form the interior seal.