A method for conditioning a load bearing surface includes positioning an oriented polymeric membrane in a mount and applying a force to the polymeric membrane so as to create a stress in the membrane. The stressed membrane is heated to a temperature no less than about a temperature that the load bearing surface is expected endure in use. The membrane is maintained at the temperature for a first period of time sufficient to heat the entirety of the membrane and the it is cooled while maintaining the stress on the membrane. Following a predetermined cool down period, the applied stress is removed for availability of the end use product. A seating surface for use in a vehicle that is subjected to an elevated temperature is also disclosed.

A method for conditioning a load bearing surface includes positioning an oriented polymeric membrane in a mount and applying a force to the polymeric membrane so as to create a stress in the membrane. The stressed membrane is heated to a temperature no less than about a temperature that the load bearing surface is expected endure in use. The membrane is maintained at the temperature for a first period of time sufficient to heat the entirety of the membrane and the it is cooled while maintaining the stress on the membrane. Following a predetermined cool down period, the applied stress is removed for availability of the end use product. A seating surface for use in a vehicle that is subjected to an elevated temperature is also disclosed.

To realize a noble, useful seat with a simple structure designed to follow a natural movement of a seated person in front-rear and left-right directions and to support appropriately a movement of the person continuously changing its posture while the person balances a load. The seat includes the elastic support layer 3 and upper and lower base units 4 and 5 arranged to sandwich the elastic support layer 3. The upper base unit 4 includes the rolling surface 42e bulging toward the lower base unit 5 thereabove via the elastic support layer 3, is rollable in a 360° direction from the tilt reference position IRP in receiving a load of the seated person, and has a moving distal end side tilting more downward as a distance from the position IRP increases, and is configured to move while compressing the elastic support layer 3 by the rolling surface.

An adjustable chair frame with a back and seating surfaces that flex to conform to the shape, weight and movement of an occupant is disclosed. The chair form and proportions provide for a recumbent position that disperses the weight of the occupant more evenly, thereby reducing external and internal physiological point loading. The form also provides ergonomic articulation to minimize internal physiological stresses such as neck/back vertebral compression. Eccentric connections driven by a motor assembly allow positioning adjustment of the components of the chair. Additionally, an air pump assembly may be included to automatically adjust one or more air bladders provided on the interior of the chair frame.

[Problem] Provided is a chair capable of changing an operation of a movable part between allowed and suppressed states, without causing an up-down movement of a seat or without requiring a complicated structure relying on a back. [Solution] For that purpose, a weight-receiving part 50, the height position of which changes due to a person sitting on a seat surface, is provided on a seat 5, the change of the height position is mechanically transmitted to a control mechanism 8X configured to control an operation of a front-rear swing part 3 being the movable part, and the control mechanism 8X changes an operation of the front-rear swing part-3 being the movable part between allowed and suppressed states.

[Problem] Provided is a chair capable of changing an operation of a movable part between allowed and suppressed states, without causing an up-down movement of a seat or without requiring a complicated structure relying on a back. [Solution] For that purpose, a weight-receiving part 50, the height position of which changes due to a person sitting on a seat surface, is provided on a seat 5, the change of the height position is mechanically transmitted to a control mechanism 8X configured to control an operation of a front-rear swing part 3 being the movable part, and the control mechanism 8X changes an operation of the front-rear swing part-3 being the movable part between allowed and suppressed states.

A completely integrated metallic seat pan with a negative stiffness includes a seat pan base, an internal metallic lattice, and a metallic seat pan cover surrounding the metallic lattice. The metallic lattice and seat pan cover elastically deform to absorb the weight of the crewmember and provide cushioning. The seat pan cover is contoured. Portions of the contoured seat pan cover may have greater or lesser cross-sectional thickness to provide variable negative stiffness at different locations on the seat pan.

A completely integrated metallic seat pan with a negative stiffness includes a seat pan base, an internal metallic lattice, and a metallic seat pan cover surrounding the metallic lattice. The metallic lattice and seat pan cover elastically deform to absorb the weight of the crewmember and provide cushioning. The seat pan cover is contoured. Portions of the contoured seat pan cover may have greater or lesser cross-sectional thickness to provide variable negative stiffness at different locations on the seat pan.

An inflatable cushion for body support is described. The inflatable cushion can be adjusted to manually/automatically set the proper pressure distribution, remove pressure from sensitive regions, alternate pressure, facilitate moisture removal, automatically detect leakage and avoid bottom down, communicate leakage and other problems with the user/caregiver, detect wrong positioning and facilitate position correction. The inflatable cushion can be used either as a chair cushion such as for example as a cushion for wheelchair or as a bed mattress.

A portable lumbar support and ergonomic chair having a lumbar support. The lumbar support has a seat hingedly coupled to a seat back having a teardrop-shaped lumbar support seat back cushion. A rigid back support portion may be rotated forward about hinges to collapse substantially parallel to the seat frame and backward to open to a variety of angles with respect to the seat frame. The seat back freely pivots around an upper lateral axis, and the rigid back support portion is linearly adjustable to space the seat back toward and away from the hinges to enable raising or lowering the upper lateral axis and thus the seat back with respect to the lower lateral axis. This provides multiple ways of changing which part of the teardrop-shaped lumbar support curve hits your lumbar curve for proper support. Variable lumbar lordotic support is thus provided.