Abstract: A vehicle seat assembly is provided having a inflatable bag positioned within its seat cushion. The bag comprises first and second fabric members joined by a rib fabric member. Each first and second member is a laminate consisting of a meshed middle fabric sandwiched between two thermoplastic resin layers adhered to one another via the meshes. Only the outer peripheries of the two resin layers are in direct sealing contact with one another. An air port is sealingly connected to the first or second member to allow air to be supplied or removed from the bag to change its contour.

Abstract: A support cushion has a flexible, airtight casing having a support layer on one side defining a support surface for being engaged by a portion of a body to be supported. A resilient layer of foam is disposed within the casing generally coextensive with the casing support layer support surface for normally urging the casing toward an expanded condition. A fluid-filled pad is positioned within the casing adjacent the additional foam material. A valve is mounted to the casing for communicating with the interior of the casing and is operable for preventing or permitting flow of air through the valve into and out of the casing.

Abstract: A lumbar frame is arranged, movable up and down, in a lower frame through second air mats which is attached to the seat back frame of a seat to correspond to the lumbar of a person who is seated on the seat, support brackets are attached, movable forward and backward, to both ends of the lumbar frame through link mechanisms and first air mats, a lumbar support member such as the zigzag or wave-formed spring is stretched between the support brackets, and an air supply and discharge means is used to supply and discharge air to and from the air mats to adjust the lumbar support member upward, downward, forward and backward.

Abstract: In a vehicle seat, particularly a motor vehicle seat, the back rest of which includes at least one forwardly projecting side wing in the area supporting the shoulders of the user. The side wing is provided with at least one recess in which an air bag and actuating device is located. Upon lateral impact the air bag inflates to protect the sideways movement of the user's head.

Abstract: A body-supporting device forming the seat (1) and/or the backrest (15) of a chair and adapted to avoid sweating caused by the thermal insulation of the chair includes at least those sections (2) of the exterior surface of the device that form the support surfaces for parts of the body of a person sitting in the chair made of air-permeable material, an internal bag member (6) having air opening (11) to the exterior of the device arranged to communicate with the interior side of the air-permeable sections (2) through holes (7) and a suction device capable of producing a negative air pressure connected to the opening.

Abstract: A seat assembly with an inflatable bladder for adjustable seat support having an air delivery system for both inflating and deflating the bladder. The air delivery system includes a single, one-directional pump and valve means selectively operable to communicate the pump outlet with the bladder and the pump inlet with atmosphere for inflating the bladder and selectively operable to communicate the pump inlet with the bladder and the pump outlet with atmosphere to deflate the bladder.

Abstract: The present device relates to a couch, which is comprised of a flexible material (Poly Vinyl Chloride) completely filled with water. The inside of the couch (all the pillows and cushion) is sectioned off by many walls of partitions, some are situated vertically affixing the upper surface to the lower surface from the front edge to the back edge and some are situated longitudinally affixing the left side edge to the right side edge. These walls are made of the same flexible material as the couch. They keep the water at minimum motion. Thus enabling a human body to sit on the couch without excess movement of water. A person can lean on the couch or sit on the edge of the couch without the water escaping that particular pressure point.

Abstract: The present invention entails a seat structure including a water bladder that serves to support an individual disposed on the seat structure. In particular, the seat structure is contoured so as to form a well cavity intermediately between a leg support area and an inclined back. Formed in the well cavity is a displaceable water well. When an occupant sits on the water well the water therein is displaced upwardly along the inclined back and provides a padding and support structure about the back of the individual occupying the seat.

Abstract: A bed pad, an automobile seat pad, a pillow or a similar cushionlike item having therapeutic effects similar to those of finger pressure therapy, a good airing function and an improved adaptability to the head or waist of the user is provided. A cushionlike item according to the present invention has a series of continuously arranged bag portions containing a large number of stuffing elements of synthetic resin.

Abstract: A portable self-contained pneumatic cushion device containing a multiple cell hermetically sealed thermoplastic air bladder within a fabric cover. A pneumatic charging valve is located in one bladder cell which acts as a plenum and a contour control valve is located within another cell. The contour control valve is connected by flexible conduits with the cells and may be opened to circulate air freely between all cells or closed to pneumatically isolate the individual cells. The contour control valve is operated by a finger-pressure squeezing action placed on valve indicators located on the surface of the fabric cover. The cushion can be instantly and simultaneously asymmetrically contoured on both faces by the user to conform to and support an irregularly shaped load applied to both faces of the cushion.

Abstract: A multiple inflatable/deflatable seat cushion bladder system has bladders arranged to receive pressurized air from one source without having fluid communication between the separate bladders when they are deflated or when an external load increases the pressure in one of the bladders. Input tubes are connected to the bladders and an inflation valve is connected to the input tubes for permitting fluid flow into the bladders while preventing fluid flow out of each of the bladders. An output tube is connected to the each bladder, and a deflation valve is connected to the output tubes for permitting fluid flow out of each bladder while preventing cross flow between the bladders. A switch assembly connected to the inflation valve and to the deflation valve allows the pressure in the bladders to remain constant or to be selectively increased or decreased.

Abstract: The present invention pertains to a structure resistant to the transmission of forces of impact which is useful in the fabrication of articles subjected to impact forces by the user of the articles. The structure includes a double plush-like open mesh structure having first and second layers of interlaced stretch-resistant flexible strand material positioned adjacent each other, and defining an intermediate space therebetween. A plurality of elongated partitions are disposed between the first and second layers and divide the intermediate space into a plurality of elongated generally parallel channels. The partitions each comprise a plurality of pile stretch-resistant strand material connecting with the first and second layers in a plane generally perpendicular to the first and second layers.

Abstract: An inflatable article comprises a peripheral inflatable member adapted to be folded on itself about a line, defining two generally similar parts, thereof; and a cushion member attached to the peripheral member along the inside of one of the parts. When folded, the article can be in the form of a chair.

Abstract: An inflatable seat cushion is positioned on a firm support on which a user is seated for assisting the user in rising from a seated position. The cushion is in the form of a ring-shaped inflatable tube having a front and rear area in which the front area is restricted during inflation with respect to the rear area. The ratio of inflation being between the rear and front areas is in the range of three to seven times greater. The inflatable cushion is inflated under the control of the user or attendant whereby the thighs of the user are supported and are elevated by the inflation of the front area of the cushion while the user's buttocks which is seated on the cushion is simultaneously elevated about 3-7 times higher than the user's thighs thereby raising the user slowly from a sitting to a standing position in front of the support in which the cushion is positioned.

Abstract: An inflatable and deflatable cushion comprising an inflatable chamber to receive an inflating fluid and further including a plurality of folding means positioned on the cushion for providing a plurality of hinge lines is disclosed. Upon deflation of the cushion, the cushion collapses to enable folding along the hinge lines to enhance the flattening of the deflated cushion and to enable the repeated folding of the cushion into a defined configuration and a small size for easy storage. A valve means permits fluid communication into the chamber to define an inflated cushion and further permits fluid communication out of the chamber in order to provide a collapsed and deflated cushion. The valve means further includes a sound generating means activated by the inflating medium when the cushion is being deflated.

Abstract: An air supply and control apparatus has an air pump to supply air under pressure to air mattresses of an air bed. A hand control having a pair of valves functions to control the operation of the air pump to supply air to the air mattresses and vent air from the air mattresses. A second embodiment of the air supply and control apparatus has a motor driven impeller for supplying air under pressure to air mattresses. Solenoids having two coils operate valves to allow air to flow to the air mattress or vent air from the air mattress to adjust the firmness of the mattress. A normally closed switch is opened when the solenoid opens the valve. The switch turns off one coil of the solenoid. The other coil remains energized to hold the valve open. Hand controls having switches are electrically coupled to the motor and solenoids to control the operation thereof.

Abstract: A seat for a vehicle, aircraft or the like includes a seat part and a backrest whereby the backrest is provided with an integrated headrest. In order that, on the one hand, the area of the cervical spinal column-lordosis of the respective seat user is effectively supported during the driving operation and, on the other, injuries of the cervical spinal column are at least reduced in case of an impact, a continuously changeable vacuum cushion is arranged at the backrest within the area of the headrest which is adapted to be individually matched to the cervical vertebrae column-lordosis of the respective seat user by means of an extraction pump and at least one valve.

Abstract: Furniture which resides in one of a levitated position and a sunk position is disclosed. The furniture includes a bladder which is shaped to remain stable when placed on a floor and which is shaped to support a body. The bladder contains a lighter-than-air gaseous substance, such as helium, confined therein. The gaseous substance operates in conjunction with the bladder to define the furniture shape. The bladder is dimensioned to contain a sufficient quantity of the gaseous substance so that buoyancy in the atmosphere causes it to rise to a ceiling of a room when the furniture is out of use. The furniture additionally includes a tether attached to a bottom surface thereof. The furniture is moved from a levitated, out-of-use, position to a sunk, in-use, position by grasping the tether and pulling the furniture downward from the ceiling. The furniture may then be maintained in the sunk position, wherein it rests on a floor of the room, by using the furniture in a conventional manner to support a body.

Abstract: A device for assisting invalids into and from a seated position, e.g., over a toilet. The device has a frame and a seat hingedly attached at the front thereof to a support member which is vertically slidable on the frame. A stop is associated with the hinge to prevent the seat from pivoting below the horizontal attitude. An extendable arm is connected at one end to the frame and, at the other end thereof, to the seat between the hinge and the center of gravity. Control means selectively activates extension of the arm to initially vertically elevate the seat in the horizontal attitude, and then to pivot the seat upwardly to assist an individual seated thereon into a standing position; or activates retraction of the arm to initially pivot the seat into a horizontal attitude, and then to vertically lower the seat in a horizontal attitude to assist an individual into a seated position.

Abstract: A headrest for an automotive seat which comprises a head contact portion, a stretchable rear portion which includes an elastic webbing, and an air bag disposed within those two portions, all of them being fixed upon the top of seat back of the seat. The expansion or shrivelling of the air bag, by using an air pump, causes the headrest to raise for turning upright the head contact portion, or permits the air bag to be compressed by the contracting force of the webbing, thereby lowering the headrest.

Abstract: A pneumatic cushion having preinflated sealed cells with pressure compensators for distributing air between cells in response to loads placed thereon, the pneumatic cushion having a mid sheet with top and bottom surfaces, a top layer of preinflated sealed cells attached to the top surface of the mid sheet, a bottom layer of preinflated sealed cells attached to the bottom surface of the mid sheet, and pressure compensators affixed to the mid sheet and in communication with each top and bottom cell whereby upon uneven loading of the sealed cells air is stepwise transferred by the pressure compensators from a cell of high pressure on a first layer to a cell on a second layer and then to another cell on the first and so on to smooth out the uneven pressure.

Abstract: A cushion body of a seat for vehicles is disclosed which comprises a main pad portion, front and back portions foldably, integrally connected with the corresponding forward and back edges of the main pad portion, and left and right side portions foldably, integrally connected with the corresponding left and right side edges of the main pad portion. All the pad portions are made of a foam material, and the front and back portions as well as the right and left side portions have superimposing surfaces for being superimposed on the upper surface of the main pad portion when each of those portions are folded over on to the main pad. A recessed portion is formed in one of the upper surface of the main pad portion and the superimposing surfaces of those front and back portions as well as left and right side portions, or both of all the upper surface and superimposing surfaces thereof, whereby an air bag is stored in the cavity formed by the recessed portion(s).

Abstract: A light-weight, low-profile seat cushion is attached to a body engaging sling. The cushion includes a foam base having a dished out central portion, and an envelope, partially filled with fluid, positioned over the dished out portion of the base. In the preferred embodiment, a self-supporting back support is attached to the rear of the seat cushion.

Abstract: An inflatable cushioned seating assembly and method is disclosed, which assembly and method alternates the areas of supporting contact of inflatable portions of the assembly with the body of a user seated in the seating device while providing continuous overall cushioned support to the user to thereby reduce or alleviate medical problems and/or fatigue caused by prolonged seating. The assembly includes a plurality of first and second alternating sets of elongated inflatable compartments that extend across both the seat and backrest of a seating device, with each set substantially independently supporting the user when pressurized to a pressure greater than that of the other set. Selected compartments of each set may be varied in size and/or material for support of selected contours of the user's body, for example, the lumbar region of the spine, and the compartments extend beyond the front edge of the seat portion of the seating device.

Abstract: A water chair which is particularly suitable for use by convalescent or geriatric persons and which comprises a frame having a seat portion and a backrest portion, a plurality of bag-like slings secured by their upper edges to the backrest portion, and a water impermeable bag located wholly within each sling. The bag within each sling is partially filled with water and the space within each bag which is not occupied by the water is substantially free of air whereby the bag and its containing sling will function as a cushion which supports and adapts to the shape of a user of the chair. The bag within each sling is secured to and suspended within the sling so that it does not collapse upon itself when partially filled with water.

Abstract: A booster seat is provided having an inflatable lower portion which can be generally donut-shaped and an inflatable upper portion which can be generally U-shaped. The lower portion and the upper portion are hinged together whereby the inflated upper portion is folded over and is secured against the upper surface of the inflated lower portion to provide a seat pocket in which a child can sit.

Abstract: A seat cushion is disclosed which comprises a rectangularly extending frame having opposed side portions; a flat sheet member arranged within a space defined by the rectangular frame; connecting devices for connecting each side portion of the flat sheet member to one of the opposed side portions of the frame; a plastic panel member having side portions raised, the plastic member being disposed on the flat sheet member leaving between each of the raised side portions and corresponding one of the opposed side portions of the frame a generally wedge-shaped clearance; a cushion structure tightly mounted on the plastic panel in such a manner that side portions of the cushion structure are raised by the raised side portions of the plastic panel; and two cushion pad units respectively received in the wedge-shaped clearances defined below the raised side portions of the plastic panel member.

Abstract: An apparatus for controlling air pressure of an onboard air support system of a vehicle comprising a pump connected to the air support for supplying or discharging the air to or from the air support, a pressure sensor in association with the air support for detecting the pressure thereof, a memory for storing present pressure values for the air support, a controller for generating pump operation control data on the basis of data derived from the detection output of the pressure sensor and data of the preset pressure value stored in the memory means, and a timer for determining the period during which the pump is to be operated on the basis of control data available from the controller, and producing a control signal supplied to said pump.

Abstract: An air supply and control apparatus has an air pump to supply air under pressure to air mattresses of an air bed. A hand control having a pair of valves functions to control the operation of the air pump to supply air to the air mattresses and vent air from the air mattresses. A second embodiment of the air supply and control apparatus has a motor driven impeller for supplying air under pressure to air mattresses. Solenoids having two coils operate valves to allow air to flow to the air mattress or vent air from the air mattress to adjust the firmness of the mattresses. A normally closed switch is opened when the solenoid opens the valve. The switch turns off one coil of the solenoid. The other coil remains energized to hold the valve open. Hand controls having switches are electrically coupled to the motor and solenoids to control the operation thereof.

Abstract: A positioning device is used for the positioning of a chair seat as to its inclination, or for positioning a back-rest member of a chair. The positioning device is constructed such as usual hydropneumatic springs which can be locked by closing a passage connected to working chambers on both sides of a piston. The working chambers are filled with an operating liquid. In order to adapt the biasing force of such a positioning device, one of the working chambers is conneced with a force-measuring device, which force measuring device is provided within the force transmission path of the respective chair column. The force measuring device comprises a measuring space filled with operating liquid, and this operating liquid is in liquid connection with one of the working chambers.

Abstract: A thin inflatable elastomeric vehicle seat comprised of a pair of elastomeric sheets which are heat sealed together to define a peripheral manifold and discrete horizontal sections, pressurized with a gas to stretch the elastomeric material into its hysteresis range and then attached to a frame to provide a cushioned seat.

Abstract: A system for assisting a fighter pilot in checking the six-o'clock position. By differentially inflating bladders placed under the seat cushion of the ejection seat of a fighter, the seat cushion can be rotated to the pilot's left or right to aid the pilot in checking the space directly behind the fighter. A system controller, responsive to actions by the pilot, causes the differential inflation of the bladders and controls the rotation of left and right harness straps. The system controller can actuate solenoid valves to control the bladder inflation or can mechanically rotate a fluid valve to control the bladder inflation. The bladders can be fabricated from a resilient material so that they automatically deflate when they are vented to the ambient atmosphere and their size can be limited by placing the bladders inside a resilient casing that has a non-resilient web connecting the opposed surface of the casing.

Abstract: An air-controlled lumbar support apparatus for a vehicle seat having a base member and a backrest is provided and includes an inflatable chamber, a valve mechanism, and a pneumatic tube. The inflatable chamber is mounted within the backrest and includes at least one partition disposed across a substantial portion of the at least one inflatable chamber. The valve mechanism receives and discharges a flow of pressurized fluid. The pneumatic tube interconnects the valve mechanism and the inflatable chamber for transferring the flow of pressurized fluid. A pump is attached to the valve mechanism for injecting fluid through the valve mechanism and the pneumatic tube to inflate the inflatable chamber. A switching mechanism allows for the release of fluid out of the valve mechanism, thereby deflating the inflatable chamber, as desired.

Abstract: A vehicle seat is provided with an elastic membrane which may be selectively tensioned by a bladder. In a preferred embodiment the frequency of the seat may be selectively modified by selective inflation of the bladder. The bladder also allows the membrane to be wrapped to a frame of the seat in such a manner to increase the predicted life cycle of the seat membrane utilized.

Abstract: An improved support system for a person in a sitting attitude to vary pressures produced on affected body areas adequate to improve blood perfusion thereat. A first, primary resilient support element is provided that defines a generally centrally located opening with a second, inflatable fluid support element received therein. The inflatable support element is located to receive the ischial tuberosities thereover and is normally deflated whereby minimal pressures are generated on body areas thereover. Fluid may be supplied to the second support element to inflate same, thereby supporting a greater proportion of the body weight and lowering pressures generated on the portions contacting the first support element. A valve controllably inflates and deflates the second element. A timer may be employed to activate an air compressor to inflate the second support element after a predetermined interval.

Abstract: A seat cover for an automotive vehicle which has inflatable, transversely extending columnar portions for providing support to the seated individual, especially to the lumbar region, and heat-retaining portions, filled with a heat-retaining agent such as polyethylene glycol, interspersed among the inflatable columnar portions for accumulating ambient heat derived from sunlight and for giving off said heat when the ambient temperature drops. Means for inflating the columnar portions manually are provided.

Abstract: An inflatable cushion for motor cars, vans, recreational vehicles and the like, and which has general application to provide comfortable seating on rough, hard, cold or hot surfaces. The cushion includes an inflatable member mounted in the back section and positioned to provide support at the lower lumber region of the back of the individual seated on the cushion, and which is adjustable to the particular needs of that individual.

Abstract: A portable stadium seat for use over existing bleachers or stadium seats has a rigid frame on which an inflatable cushion is provided. The seat frame may have pivotally connected leg and head rest portions. The seat cushion may have a head rest, a lumbar support, a back rest, a seat portion and armrests all formed as separate compartments selectively connectable by a manifold valve to a footpump which is carried in a compartment in the seat cushion. A "U" shaped seat hook is pivotally connected to the underside of the seat frame and in one position, it is used to attach the seat frame over an exisiting stadium seat or bleacher, and in another position, it is received in a catch formed on the back of the seat frame to be used as a handle for transportation of the portable stadium seat.

Abstract: A field portable dental chair, collapsible to suitcase size, with pivotable outriggers for support, the chair including a bellows arrangement with a telescopic internal structure for raising and lowering the seat of the chair. The apparatus is formed, in part, of rigid members and, in part, flexible members contained within the rigid members for portability. Inflatable cushion members are provided for support of the head, back, seat and legs of a patient.

Abstract: A folding boat chair formed by a molded plastic seat member and a molded plastic back member. An integral boss on the underside of the seat member presents a socket which fits on the top end of an upright post mounted in the boat. The seat can turn on the post and can be locked in place by a clamp mechanism. Pins which are integral with the sides of the back member fit in passages in sides of the seat member to pivotally connect the members without the need for separate hinge components.

Abstract: An automobile seat having an infinitely adjustable thigh support is disclosed. The seat includes an air operated bladder mounted between a rigid extension on the seat bottom frame and a padded thigh support member pivotably mounted to the seat bottom frame at the thigh location of an occupant of the seat. The thigh support member is positionable at any of an infinite number of intermediate support positions with the thigh support cushion maintained in contact with the seat cushion at all positions of the thigh support.

Abstract: An inflatable and deflatable cushion comprising an inflatable chamber to receive an inflating fluid and further including a plurality of folding means positioned on the cushion for providing a plurality of hinge lines is disclosed. Upon deflation of the cushion, the cushion collapses to enable folding along the hinge lines to enhance the flattening of the deflated cushion and to enable the repeated folding of the cushion into a defined configuration and a small size for easy storage. A valve means permits fluid communication into the chamber to define an inflated cushion and further permits fluid communication out of the chamber in order to provide a collapsed and deflated cushion. The valve means further includes a sound generating means activated by the inflating medium when the cushion is being deflated.

Abstract: A seat has an inflatable seat base member, a back rest member and attachments for securing the seat to rigid structure of a vehicle in which it is installed. A top seating surface of the seat base member is further supported by support panel members attached one to each side end wall of the seat base member and extending upwardly to connect with vehicle rigid structure so that a supported seating surface is available for use when the seat base member is deflated.

Abstract: A water cushion assembly for a chair, constructed either as an integral assembly or as an attachment, has a plurality of horizontally-arranged vertically-spaced sections; and each of the casings is provided with an inner casing and respective valves for filling the casings with water (or other liquid) to a predetermined level. Each of the sections has a substantially oval cross-section, wherein the external surfaces of the sections are convex, yet are joined together. The front of the chair has a corresponding plurality of horizontally-arranged vertically-spaced scalloped recesses for supporting the respective sections. The assembly is removably secured to the chair by suitable straps provided with "VELCRO" fibrous fasteners (or other suitable means). Water cushion assemblies for the arm rests are also provided.

Abstract: A passive exercise cushion for alleviating and preventing back pain includes a plurality of air inflatable component members encased within a fabric covering. The covering includes a strap member for securement to a backrest of a chair. A pillow member within the casing is positioned in confronting relationship for cradling the back when sitting in the chair. A support mat within the casing provides cushion firmness. A pouch placed between the pillow member and the support mat is adjustably positionable at preselected areas, the locus of which extends between the lower limit of the scapula and the fourth lumbar vertebrae of the back. The volume of air within the pouch is controlled so that when the reclining back assumes a comfortable position in the chair, a forwardly directed force is exerted by the pouch. Bodily equilibrium is passively maintained by counterbalancing contraction of the muscles supporting the spinal system and thus provide a strengthened and conditioning action.

Abstract: An inflatable cushion is provided to be embedded in the upholstery of a motor vehicle seat. The cushion has one inflatable compartment and is typically placed near an exterior edge of a back support or seat cushion. As the inflatable cushion is inflated, the contours of the back support or seat cushion can be changed. The longitudinal interior edge of the cushion has a wave-like configuration which faces toward the central portion of the back support or seat cushion.

Abstract: An inflatable article includes at least one first gas impervious flexible sheet formed into an inflatable envelope having at least one heat-sealed edge by heat sealing, and at least one second sheet heat sealed to the first sheet to form an additional air compartment, wherein the second sheet has at least one marginal edge which is heat sealed along the heat sealed edge or along a seam adjacent to the heat sealed-edge with an adjacent portion thereof extending over the heat-sealed edge. The additional air compartment expands over and conceals the heat-sealed edge upon inflation.

Abstract: A headrest apparatus comprising at least one support member mounted on a seat, a high cushioning elastic base provided on said support member, a low cushioning elastic support wall provided on said elastic base, an empty room formed in front of said elastic support wall, a head resting part formed at the front side of this empty room and a gel material layer formed by filling said empty room with gel material, wherein a load to be applied to said head resting part is applied to said gel material layer.

Abstract: The water-filled chair or couch of the present invention includes a frame, and a bladder positioned on the frame. The bladder has a seat portion, a back portion, and a channel extending substantially across the width of the bladder so as to provide communication between the seat and back portions. The bladder is partially filled with water and is void of air such that, as a person sits down into the chair, water is forced substantially instantaneously from the seat portion through the channel and upwardly into the back portion of the bladder which expands to provide support to the person's lower back. The channel has a depth substantially less than that of the seat or back portions. A restrictor bar extends across the channel to maintain the shape thereof as water passes therethrough. A dam is provided at least on the front edge of the bladder to provide support thereto. A heating element and vibrator are provided for additional comfort.

Abstract: A product for recreational beach use is comprised of a beach-blanket type of sheet of generally rectangular shape, and an inflatable chair positioned upon the upper surface of the sheet at a site closer to the rear edge than the front edge. The chair, having a seat and an adjustable backrest portion, can be inflated either by water or by air at a pressure in the range of 5-20 psi. In preferred embodiments, the chair is removably attached to the sheet.