Blast attenuation seat

Abstract

A seat supports an occupant of a vehicle and absorbs a force between the occupant and the vehicle created by relative movement between the occupant and the vehicle. The seat includes a seat back and a seat bottom frame supporting the seat back and extending from the seat back along an axis. A seat pan is moveably coupled to the seat bottom frame and an energy absorbing device is coupled to the seat bottom frame and the seat pan. The energy absorbing device is configured to absorb at least a portion of the force between the occupant and the vehicle when the seat pan moves relative to the seat bottom frame. A link is pivotably coupled to the seat pan and to the seat bottom frame and guides movement of the seat pan relative to the seat bottom frame away from the seat back along the axis when the seat pan moves relative to the seat bottom frame.

What is claimed is: 
     
         1 . A seat for supporting an occupant of a vehicle and absorbing a force between the occupant and the vehicle created by relative movement between the occupant and the vehicle, said seat comprising:
 a seat back;   a seat bottom frame supporting said seat back and extending from said seat back along an axis;   a seat pan moveably coupled to said seat bottom frame;   an energy absorbing device coupled to said seat bottom frame and said seat pan and configured to absorb at least a portion of the force between the occupant and the vehicle when said seat pan moves relative to said seat bottom frame; and   a link pivotably coupled to said seat pan and to said seat bottom frame and guiding movement of said seat pan relative to said seat bottom frame away from said seat back along said axis when said seat pan moves relative to said seat bottom frame.   
     
     
         2 . The seat as set forth in  claim 1  wherein said link includes a first pivot point pivotably coupled to said seat pan and a second pivot point pivotably coupled to said seat bottom frame, said first pivot point being spaced a first distance from said seat back along said axis and said second pivot point being spaced a second distance from said seat back along said axis greater than said first distance. 
     
     
         3 . The seat as set forth in  claim 2  wherein said second pivot point is spaced above said first pivot point. 
     
     
         4 . The seat as set forth in  claim 1  wherein said energy absorbing device is coupled to said link for absorbing at least a portion of the force between the occupant and the vehicle when said link pivots relative to said seat pan and said seat bottom frame. 
     
     
         5 . The seat as set forth in  claim 1  further comprising a support disposed below and moveably supporting said seat bottom frame. 
     
     
         6 . The seat as set forth in  claim 5  further comprising a second energy absorbing device coupled to said support and said seat bottom frame and configured to absorb energy at least a portion of the force between the occupant and the vehicle during relative movement of said seat bottom frame and said support. 
     
     
         7 . The seat as set forth in  claim 6  wherein said second energy absorbing device supports said energy absorbing device and wherein said energy absorbing device is configured to absorb at least a portion of the force when the magnitude of the force reaches a first magnitude and wherein said second energy absorbing device is configured to absorb at least a portion of the force when the magnitude of the force reaches a second magnitude greater than the first magnitude. 
     
     
         8 . The seat as set forth in  claim 7  further comprising a third energy absorbing device supporting said second energy absorbing device and configured to absorb at least a portion of the force when the force reaches a third magnitude greater than the second magnitude. 
     
     
         9 . The seat as set forth in  claim 8  further comprising a base for connecting to the vehicle with said third energy absorbing device supporting said second energy absorbing device on said base. 
     
     
         10 . The seat as set forth in  claim 9  wherein said third energy absorbing device extends between said base and said second energy absorbing device and wherein said second energy absorbing device extends between said third energy absorbing device and said first energy absorbing device. 
     
     
         11 . The seat as set forth in  claim 8  wherein said third energy absorbing device is configured to plastically deform to absorb at least a portion of the force when the force exceeds the third magnitude. 
     
     
         12 . The seat as set forth in  claim 11  wherein said third energy absorbing device and said second energy absorbing device each resiliently move when absorbing at least a portion of the force. 
     
     
         13 . The seat as set forth in  claim 6  wherein said second energy absorbing device includes a linkage coupled to said seat bottom frame and said support and a resilient member operatively coupled to said linkage. 
     
     
         14 . The seat as set forth in  claim 13  further comprising a base for connection to the vehicle and a third energy absorbing device supporting said support on said base. 
     
     
         15 . The seat as set forth in  claim 14  wherein said energy absorbing device is configured to absorb at least a portion of the force when the magnitude of the force reaches a first magnitude and wherein said second energy absorbing device is configured to absorb at least a portion of the force when the magnitude of the force reaches a second magnitude greater than the first magnitude and wherein said third energy absorbing device is configured to absorb a least a portion of the force when the force reaches a third magnitude greater than the second magnitude. 
     
     
         16 . The seat as set forth in  claim 14  wherein said third energy absorbing device extends from said base to said support and wherein said second energy absorbing device extends from said support to said frame. 
     
     
         17 . The seat as set forth in  claim 1  further comprising an inflatable device disposed on said seat pan and configured to selectively inflate for cushioning between the occupant and said seat pan. 
     
     
         18 . A seat for supporting an occupant of a vehicle and absorbing a force between the occupant and the vehicle created by relative movement between the occupant and the vehicle, said seat comprising:
 a seat back;   a seat bottom frame supporting said seat back and extending from said seat back along an axis;   a seat pan moveably coupled to said seat bottom frame;   an energy absorbing device coupled to said seat bottom frame and said seat pan and configured to absorb at least a portion of the force between the occupant and the vehicle when said seat pan moves relative to said seat bottom frame; and   a link including a first pivot point pivotably coupled to said seat pan and a second pivot point pivotably coupled to said seat bottom frame, said first pivot point being spaced a first distance from said seat back along said axis and said second pivot point being spaced a second distance from said seat back along said axis greater than said first distance.   
     
     
         19 . The seat as set forth in  claim 18  wherein said second link is spaced above said first link. 
     
     
         20 . The seat as set forth in  claim 18  wherein said energy absorbing device is coupled to said link for absorbing at least a portion of the force between the occupant and the vehicle when said link pivots relative to said seat pan and said seat bottom frame.