Reclining seat to mitigate the effects of mine blast load on spine and lower leg injuries

A seat assembly for installation in a vehicle and operative to tilt to a reclined position in response to an upward acceleration of the vehicle, the seat assembly comprising:

• a seat frame for supporting an occupant, the seat frame comprising a seat bottom having a front edge and a rear edge, and further comprising a seat back connected with the seat bottom adjacent the rear edge and extending upward therefrom;
• an energy absorbing mechanism configured to be operatively positioned between a floor of the vehicle and the seat frame to absorb energy transferred to the seat frame by the upward acceleration of the vehicle, an upper end of the energy absorbing mechanism being connected to the seat frame by a pivotal connection nearer the front edge of the seat bottom than the rear edge;
• a stop mechanism incorporated in the pivotal connection, the stop mechanism preventing rearward tilting of the seat assembly about the pivotal connection when less than a predetermined amount of tilting force acts on the seat assembly;
• a dog-leg lever adapted to be pivotably connected to the floor at a location rearward, relative to the seat frame, of the energy absorbing mechanism, the dog-leg lever having a foreleg configured to be positioned adjacent to a zone of the floor forward of the front edge of the seat bottom and an aft leg configured to extend rearward from the foreleg;
• and
• a strut extending between the aft leg and the seat frame rearward of the pivotal connection between the energy absorbing mechanism and the seat frame such that, when the seat assembly is installed in the vehicle, an upward force applied to the foreleg by the floor causes a pivoting motion of the dog-leg lever wherein the aft leg and the strut move downward and urge the seat frame to a reclined position.

An energy absorbing seat assembly for installation in a vehicle, the energy absorbing seat assembly comprising:

• a seat frame for supporting an occupant, the seat frame comprising a seat bottom having a front edge and a rear edge, and further comprising a seat back connected with the seat bottom adjacent the rear edge and extending upward therefrom;
• a compressible energy absorbing mechanism operatively configured to be positioned between a floor of the vehicle and the seat frame to absorb energy transferred to the seat frame by an upward acceleration of the vehicle when installed therein, an upper end of the energy absorbing mechanism being connected to the seat frame by a pivotal connection disposed nearer the front edge of the seat bottom than the rear edge;
• a stop mechanism operative to prevent rearward tilting of the seat assembly about the pivotal connection when less than a predetermined amount of tilting force acts on the seat assembly, wherein the stop mechanism provides controlled resistance to tilting of the seat assembly through a range of rearward tilting movement after the predetermined amount of tilting force is exceeded;
• a dog-leg lever adapted to be pivotably connected to the floor at a pivot location rearward, relative to the seat frame, of the energy absorbing mechanism, the dog-leg lever having a foreleg configured to be positioned adjacent to a floor zone forward of the front edge of the seat bottom and an aft leg configured to extend rearward from the foreleg;
• and
• a strut extending between the aft leg and the seat frame rearward of the pivotal connection between the energy absorbing mechanism and the seat frame such that, when the seat assembly is installed in the vehicle, upward movement of the floor zone relative to the pivot location urges the foreleg upward and the aft leg downward and places the strut in tension to apply a force to the seat frame tending to pull the seat frame to a reclined position.

A combination of a seat assembly and associated structure configured to be installed in a vehicle and to recline the seat assembly in response to an upward acceleration of the vehicle so as to mitigate injury to a human occupant when seated in the seat assembly, the combination comprising:

• a seat assembly frame;
• a back frame portion of the seat assembly frame;
• a lower frame portion of the seat assembly frame extending forward from the back frame portion;
• a means for absorbing energy applied to the seat assembly frame from the upward acceleration;
• a seat pivotal connection between the lower frame portion and the energy absorbing means;
• a dog-leg lever having a foreleg and an aft leg and a junction between the foreleg and the aft leg;
• a pivot connection configured to couple the junction and a floor of the vehicle, the pivot connection being disposed more rearward relative to the seat assembly frame than the energy absorbing means;
• wherein the foreleg is configured to extend forward relative to the seat assembly frame and to be disposed over the floor forward of the pivot connection when the combination is installed in the vehicle;
• and
• a strut pivotally connected between the aft leg and the back frame portion of the seat assembly frame, the strut being under tension when the seat assembly frame is in an unreclined position.

A seat assembly for installation in a vehicle and operative to tilt to a reclined position in response to an upward acceleration of the vehicle, the seat assembly comprising:

• a seat frame for supporting an occupant, the seat frame comprising a seat bottom having a front edge and a rear edge, and further comprising a seat back connected with the seat bottom adjacent the rear edge and extending upward therefrom, the seat bottom and the seat back being rigid and fixed relative to one another;
• an energy absorbing mechanism configured to be operatively positioned between a floor of the vehicle and the seat frame to absorb energy transferred to the seat frame by the upward acceleration of the vehicle, an upper end of the energy absorbing mechanism being connected to the seat frame by a pivotal connection nearer the front edge of the seat bottom than the rear edge;
• a dog-leg lever adapted to be pivotably connected to the floor at a location rearward, relative to the seat frame, of the energy absorbing mechanism, the dog-leg lever having a foreleg configured to be positioned adjacent to a zone of the floor forward of the front edge of the seat bottom and an aft leg configured to extend rearward from the foreleg;
• and
• a strut extending between the aft leg and the seat frame rearward of the pivotal connection between the energy absorbing mechanism and the seat frame such that, when the seat assembly is installed in the vehicle, an upward force applied to the foreleg by the floor causes a pivoting motion of the dog-leg lever wherein the aft leg and the strut move downward and urge the seat frame to a reclined position.

A seat assembly for installation in a vehicle and operative to tilt to a reclined position in response to an upward acceleration of the vehicle, the seat assembly comprising:

• a seat frame for supporting an occupant, the seat frame comprising a seat bottom having a front edge and a rear edge, and further comprising a seat back connected with the seat bottom adjacent the rear edge and extending upward therefrom;
• an energy absorbing mechanism configured to be operatively positioned between a floor of the vehicle and the seat frame to absorb energy transferred to the seat frame by the upward acceleration of the vehicle, an upper end of the energy absorbing mechanism being connected to the seat frame by a pivotal connection nearer the front edge of the seat bottom than the rear edge;
• a dog-leg lever adapted to be pivotably connected to the floor at a location rearward, relative to the seat frame, of the energy absorbing mechanism, the dog-leg lever having a foreleg configured to be positioned adjacent to a zone of the floor forward of the front edge of the seat bottom and an aft leg configured to extend rearward from the foreleg;
• and
• a strut extending between the aft leg and the seat frame rearward of the pivotal connection between the energy absorbing mechanism and the seat frame such that, when the seat assembly is installed in the vehicle, an upward force applied to the foreleg by the floor causes a pivoting motion of the dog-leg lever wherein the aft leg and the strut move downward and urge the seat frame to a reclined position;
• and wherein
• at least one of the energy absorbing mechanism and the strut is a plastically deformable element.