Abstract: Present embodiments provide various open coil spring assemblies which perform like an encased spring assembly. The embodiments have elastic lacings or connections which connect springs to springs or springs to lacings. Various spring embodiments are provided as well as various arrangements for the elastic lacings. All of these features improve compliance and stability while reducing motion transfer.

Abstract: A pocketed spring assembly comprises a plurality of parallel strings of springs, each string joined to at least one adjacent string, each string comprising first and second opposed plies of fabric and a plurality of pockets formed along a length of the string by transverse seams joining the first and second plies. At least one spring is positioned in each pocket. Exterior strings have identical springs in their pockets. Interior strings have two different springs along their length, the outermost springs being firmer than the interior core springs. The pocketed spring assembly has increased firmness or edge support along all four sides due to the different coil springs of the assembly.

Abstract: A support structure and vertical isolation structure may include a plurality of spring coils and a mesh network. Each spring coil of the plurality of spring coils includes a spring, a cap, and a floating connector. The cap is configured to engage the spring. The floating connector is disposed in a middle of the spring. The mesh network secures a first spring coil of the plurality of spring coils to a second spring coil of the plurality of spring coils by passing through the floating connector of each of the first spring coil and the second spring coil.

Abstract: A coil-in-coil spring is provided that exhibits a variable and non-linear loading response. The spring includes a first spring portion having a first spring constant, a second spring portion having a second spring constant less than the first spring constant, and a third spring portion having a third spring constant less than the first spring constant and less than the second spring constant. The first spring portion forms an outer coil of the coil-in-coil spring and the second spring portion, the third spring portion, or both the second spring portion and the third spring portion are positioned within the first spring portion and form an inner coil of the coil-in-coil spring. A multi-coil spring is also provided that includes an outer coil, an intermediate coil positioned within the outer coil, and an inner coil positioned with the intermediate coil.

Abstract: A spring is provided that exhibits a variable and non-linear loading response upon compression. The spring comprises a continuous wire having a lower end convolution, an upper end convolution, and a plurality of helical intermediate convolutions. The upper end convolution, the lower end convolution, and the helical intermediate convolutions each have a respective diameter, with the continuous wire further defining a pitch between the various convolutions. In the spring, one or more of the diameters of the convolutions or one or more of the pitches varies along the length of the continuous wire such that the spring exhibits a non-linear loading response upon compression. A mattress is further provided and includes a plurality of the springs arranged in a matrix.

Abstract: A pocketed spring assembly comprises a plurality of parallel strings of springs, each string joined to at least one adjacent string, each string comprising first and second opposed plies of fabric and a plurality of pockets formed along a length of the string by transverse seams joining the first and second plies. At least one spring is positioned in each pocket. Exterior strings have identical springs in their pockets. Interior strings have two different springs along their length, the outermost springs being firmer than the interior core springs. The pocketed spring assembly has increased firmness or edge support along all four sides due to the different coil springs of the assembly.

Abstract: An article of protective equipment includes a one-piece body. The body includes a first region, an edge, and a second region. The first region is formed from a first composite material having a first matrix component and a first reinforcement component. The second region extends between the first region and the edge. The second region is formed from a second composite material having a second matrix material and a second reinforcement component. One of the first reinforcement component and the second reinforcement component has a plurality of first items arranged randomly. The other of the first reinforcement component and the second reinforcement component has a plurality of second items arranged in a predetermined arrangement. The body is configured to protect the wearer from an input load, and the second region is configured to flex under the influence of the input load.

Abstract: A seat support assembly supports a cushion of a furniture member. The seat support assembly may include a frame, at least two seat springs, a support spring, and a coil spring. The support spring may be positioned between two seat springs, and the seat springs and the support spring may extend across the frame. A coil spring may be positioned on and attached to the support spring. The coil spring may extend to and bias against the two seat springs positioned on either side of the support spring.

Abstract: A cover system includes a first layer providing a top surface over a patient support structure. A layer of spacer material is provided beneath the first layer. An air mover moves air through the layer of spacer material to remove moisture adjacent a person supported by the patient support.

Abstract: Disclosed herein is a method of making a spring core (12) for a bedding or seating product (10). The spring core (12) has coil springs (26) having unknotted end turns (72, 74) made from high tensile strength wire. In each embodiment, the end turns (72, 74) of the coil springs (26) are generally U-shaped having one arcuate leg (76) longer than the other (78), the legs (76, 78) being joined by a connector (80) having an arcuate bump (81) therein. The springs (26) are oriented in the spring core (12) such that a long leg (76) of one end turn (72) abuts a short leg (78) of the adjacent end turn (72) prior to being wrapped in helical lacing wire (32). The high tensile wire enables the coil springs (26) to be manufactured using less wire than heretofore possible.

Abstract: The invention relates to the field of furniture, and in particular to a cushion or mattress suspension element 101, 201, . . . , 901 comprising a compressible core 102, 202, . . . , 902 of flexible material and presenting at least one compression axis Z, and also comprising two bearing parts 103, 203, . . . , 903 of material that is substantially more rigid than the material of the compressible core 102, 202, . . . , 902, with at least a first bearing part being connected to one end of the compressible core 102, 202, . . . , 902 and at least one second bearing part being connected to an end of the compressible core 102, 202, . . . , 902 that is opposite along the compression axis Z, and with each bearing part presenting an outer bearing area 103a, 203a, . . . , 903a that is substantially perpendicular to said compression axis Z and, in at least one direction perpendicular to the compression axis Z, that is substantially larger than the compressible core 102, 202, . . . , 902 in its relaxed position.

Abstract: A fuel cell stack and a compression system for providing compressive force to a fuel cell stack having first and second ends is provided. The compression system includes asymmetric leaf springs operatively connected to first and second ends of the fuel cell stack. Each leaf spring includes a slot having first and second connector positions. The compression system also includes tension members connected to the leaf springs. The tension members compress the leaf springs to provide a compressive load to the fuel cell stack.

Abstract: Encased coil units with advance conforming properties have various interconnections and structures between individually encased or wrapped coils. In the various embodiments, encasement structures between coils such as closure or attachment of sheet material or fabric, which encase the coils, are configured to allow and enhance independent movement of coils with respect to adjacent coils and remote coils of the unit. Modifications in the sheet material or fabric which encases the coils include variations in the points of connection or disconnection between adjacent coils, such as slits in the material proximate to top ends of the coils in a continuous string, or the absence of welds or glue points between adjacent encasements or strings of encasements, proximate to top ends of the coils to allow more freedom of movement of the top or upper ends of the coils and with respect to adjacent coils, and to reduce load transfer or cratering of the coil springs about the locus of the force vector.

Abstract: The invention describes a coated spring for mattresses that comprises a helical compression spring and a wrapping in the form of a bag containing the spring, wherein the bag containing the spring is injected with a polymeric reaction mixture, which after reacting or curing produces a polymeric foam, preferably of flexible polyurethane up to a desired volume in order to cause the spring to change its flexion or compression properties, as well as the method for its manufacturing and its use in the manufacturing of mattresses of different kinds.

Abstract: Encased coil units with advance conforming properties have various interconnections and structures between individually encased or wrapped coils. In the various embodiments, encasement structures between coils such as closure or attachment of sheet material or fabric, which encase the coils, are configured to allow and enhance independent movement of coils with respect to adjacent coils and remote coils of the unit. Modifications in the sheet material or fabric which encases the coils include variations in the points of connection or disconnection between adjacent coils, proximate to top ends of the coils to allow more freedom of movement of the top or upper ends of the coils and with respect to adjacent coils, and to reduce load transfer or cratering of the coil springs about the locus of the force vector.

Abstract: A bedding or seating product comprising a spring core including upper and lower border wires. Each of the border wires is generally rectangular in cross-section to reduce wire costs without compromising beam strength of the border wire. Each row of springs of the spring core may be made of a single piece of wire. The rows of springs may be arranged in side-by-side rows and columns and be connected with each other by helical lacing wires.

Abstract: An apparatus is provided for applying adhesive to a string of pocketed coil springs during manufacture of an innerspring assembly, which apparatus comprises a plurality of independently actuatable adhesive applicators, each having a different transverse position relative to a longitudinal axis of the string of pocketed coil springs, and means for causing relative movement between the string of pocketed coil springs and the plurality of adhesive applicators, along a longitudinal axis of the string. The apparatus is adapted to apply adhesive to the string of pocketed coil springs, during relative movement between the first string of pocketed coil springs and the plurality of adhesive applicators, in a pattern that varies between at least some pockets of the string of pocketed coil springs.

Abstract: A resilient unit suitable for providing comfort, convenience, support or protection is described. The unit typically takes the form of a pad comprising a plurality of pocketed coil springs arranged in an array, each spring being substantially encased in an individual pocket, and the unit being compressible in the axial direction of the springs, wherein each spring comprises a number of coils, and in respect of at least some springs the coils at opposed ends are of different diameter.

Abstract: A mattress assembly may include a foam frame, an inner assembly within the foam frame, the inner assembly including a foam core and a pocketed coil assembly. The pocketed coil assembly can include a plurality of individual pocketed coil springs having a height. Each coil spring may be joined together to a neighboring coil spring such that at least a majority of the height of each coil spring is configured to vertically deflect without deflecting the joined neighboring coil spring.

Abstract: A drop-in grid base for coil units is provided. A plurality of extruded plastic tubes, plastic-covered wire profiles, and cross wires are arranged in substantially the same plane to form a grid foundation. The cross wires intersect the extruded plastic tubes and wire profiles. Base wires having a series of shallow, v-shaped notches are interwoven in substantially the same plane as the grid foundation. The ends of the base wires are looped for attachment inside the seating cavity of a framed furniture product. A coil unit may be attached directly to the drop-in grid base. Alternatively, the drop-in grid base may be separately installed into a seating cavity frame, for later installation of a coil unit on top of the drop-in grid base.

Abstract: A bedding or seating product comprising a spring core including upper and lower border wires. Each of the border wires is generally rectangular in cross-section to reduce wire costs without compromising beam strength of the border wire. Each row of springs of the spring core may be made of a single piece of wire. The rows of springs may be arranged in side-by-side rows and columns and be connected with each other by helical lacing wires.

Abstract: Encased coil units with advance conforming properties have various interconnections and structures between individually encased or wrapped coils. In the various embodiments, encasement structures between coils such as closure or attachment of sheet material or fabric, which encase the coils, are configured to allow and enhance independent movement of coils with respect to adjacent coils and remote coils of the unit. Modifications in the sheet material or fabric which encases the coils include variations in the points of connection or disconnection between adjacent coils, proximate to top ends of the coils to allow more freedom of movement of the top or upper ends of the coils and with respect to adjacent coils, and to reduce load transfer or cratering of the coil springs about the locus of the force vector.

Abstract: Device, system, and method of injected padding. A seating assembly comprises: a support surface associated with an assembly base via at least partially two or more injection molded elastic elements; wherein said elastic elements are composed of a raw plastic material; wherein said two or more elastic elements are formed concurrently as part of a single injection molding.

Abstract: A spring mattress includes a plurality of strings interconnected side by side, each string including a continuous casing material with a plurality of pockets, said pockets being defined by at least one longitudinal connecting line extending parallel to the longitudinal direction of the string and a plurality of transverse connecting lines extending transversely to the longitudinal direction of the string, and coil springs arranged in the pockets of the string. For at least one of the springs, casing material portions arranged at the ends of the spring are moved towards each other, through the spring, and connected to each other. The connecting lines are arranged at the side of the springs and, thus, between neighboring springs. The interconnected casing material portions are thus at the ends of the springs essentially free of other connections.

Abstract: A spare tire dynamic damper for a vehicle comprises a mounting frame, at least one support plate, and a moveable spare tire attachment plate spaced between the at least one support plate and the mounting frame, wherein the spare tire attachment plate is configured to move in the space between the mounting frame and the at least one support plate. In this embodiment, the spare tire dynamic damper comprises a pair of coil springs, wherein each coil spring is extended from opposite faces of the spare tire attachment plate, and one or both of the coil springs is configured to oscillate upon the movement of the spare tire attachment plate.

Abstract: Package (10) of flat-packing multiple pocketed spring core assemblies (12) wherein a stack of multiple pocketed spring assemblies (12) are trapped between a pair of wooden frames (16). After compression of the stack including the wooden frames (16), bands (28) are tightly wrapped around the compressed stack. Loops of wire (32) are then inserted through the stack and wrapped about at least one cross element (34) of the frame (16) on each side of the stack. Each loop of wire (32) is pulled taut and its opposite ends connected together so as to prevent the center portion of the stack from ballooning outwardly after removal of compression forces on the rigid frames.

Abstract: Innerspring coils for innersprings for mattresses and other reflexive support structures, have generally helical coil bodies and at least one non-helical segment or step which extends between one or both axial ends of the coil body and one or both of the coil ends. The step or steps may be linear or non-linear, and parallel to or angularly disposed with respect to a longitudinal axis of the coil body. When located proximate to a coil end, the step extends out of the plane in which the coil end lies. One or more steps may alternatively be formed intermediate to helical turns of the helical coil body.

Abstract: Disclosed herein is a bedding or seating product (10) having a spring core (12) comprising coil springs (26) having unknotted end turns (72, 74) made from high tensile strength wire. In each embodiment, the end turns (72, 74) of the coil springs (26) are generally U-shaped having one arcuate leg (76) longer than the other (78), the legs (76, 78) being joined by a connector (80) having an arcuate bump (81) therein. The springs (26) are oriented in the spring core (12) such that a long leg (76) of one end turn (72) abuts a short leg (78) of the adjacent end turn (72) prior to be wrapped in helical lacing wire (32). The high tensile wire enables the coil springs (26) to be manufactured using less wire than heretofore possible.

Abstract: Asymmetric spring components for mattress and other flexible support structures, in the form of helical coil springs with turns in the coil body having varying pitch angles and radii, and a single support end for use in a one sided innersprings in one-sided mattresses. The coil springs are asymmetric about an axis of the coil or a horizontal reference plane, or both, and with ends of the coil springs shaped and sized differently to accommodate different mounting and support arrangements. Asymmetric coil springs can be contained in individual pockets or strings of pockets and arranged together to form an asymmetric pocketed coil innerspring for use in a one-sided mattress.

Abstract: The invention concerns a mattress spring structure that includes multiple spring assemblies. Each spring assembly comprises an array of open-ended spring coils. The spring assemblies are arranged in superimposed relationship with the individual spring coils of the respective assemblies registering in vertical alignment with one another. A membrane extends between each pair of superimposed assemblies and the assemblies are connected to one another to form a unitary structure.

Abstract: A spring mattress comprising a plurality of interconnected coil springs (1) enclosed in covers (2), known as a pocket-spring mattress, is described, wherein at least two springs that are located adjacent to one another are spaced apart by an interjacent separation distance (SA), said separation distance exceeding approximately 10% of the diameter of the largest one of the spiral turns of the adjacent springs. Also described is a method of manufacturing a corresponding mattress.

Abstract: The invention concerns inner spring assemblies for mattresses, typically bed mattresses. The invention proposes an inner spring assembly having open-ended coil springs arranged in first rows and second rows transverse to the first rows and a connecting arrangement which connects the coil springs to form a unitary assembly. For ease of manufacture all the coil springs in the assembly are of the same hand, those in the first rows are oriented similarly to all other springs in the same first row and in at least some of the second rows there are springs which are oriented oppositely to other coil springs in the same second row.

Abstract: A mattress comprises a support plate having a plurality of mounting holes, a plurality of independent spring assemblies individually mounted to the support plate, and a cover enclosing the support plate and the plurality of spring assemblies. Each of the spring assemblies includes a tubular mounting member fixed to the support plate preferably by snap-fit through a mounting hole in the support plate, a sliding cap axially movable relative to the mounting member, and a spring acting between the mounting member and the sliding cap, wherein the spring is axially compressible when the sliding cap is forced in an axial direction toward the support plate. A spacer of chosen length can be provided to set preload on the spring. In a “flippable” embodiment, the mounting member includes a mid-portion snap-fitted to the support plate and upper and lower portions each having a sliding cap associated therewith, wherein the spring acts between the two sliding caps.

Abstract: A spring coil assembly having a first row of coils arranged in a first spacing pattern and a second row of coils adjacent the first row and arranged in a second spacing pattern that is different from the first spacing pattern. The spring coil assembly can be assembled using an apparatus comprising a main conveyor adapted to convey a plurality of coils along an axis, an assembler which is operable to intertwine a plurality of coils into a spring coil assembly, and a transfer station operable to move a plurality of coils from the main conveyor into the assembler. The transfer station includes a plurality of pusher arms each of which include a gripper which is operable to grasp an individual coil, a carriage supporting the gripper arms and means for shifting the carriage axially relative to the axis so that a plurality of coils carried by the gripper arms are displaced in the direction of travel of the conveyor.

Abstract: A pocketed coil spring unit and associated method of assembly combines top and bottom sheets with bonding of the sidewalls of adjacent rows of pocketed coil springs. With this combination, a posturized spring unit is produced in a commercially efficient manufacturing process. The top and bottom sheets extend perpendicularly to the rows of pocketed coil springs and the adjacent rows of pocketed coil springs are bonded on the sidewalls of the fabric pockets in the absence of the top and bottom sheets. As such, the spring unit can be customized for posturization to provide a firmer supporting foundation at the locations of the top and bottom sheets and a more individualized flexible construction in the regions of the inter-row sidewall bonding.

Abstract: A coil spring assembly for use in the manufacture of bedding and seating products or the like comprising a plurality of bands of coil springs joined together with helical lacing wires. Each of the bands of coil springs is made of one piece of wire formed into a row of coil springs. The helical lacing wires are spaced inwardly from the end turns of the coil springs, thereby creating a cushioning affect on at least one surface of the product.

Abstract: The invention relates to a spring mattress comprising a plurality of interconnected coil spring elements, whereby the mattress includes at least two layers extending in parallel with the plane on the mattress and each exhibiting different properties of resilience. The feature characterizing the mattress in accordance with the invention are that the same coil springs extend across both the layers and that these coil springs exhibit a higher degree of bias only along part of their extension, thus forming the layers exhibiting different properties of resilience.

Abstract: A pocketed coil spring assembly for use in the manufacture of mattresses or cushions or the like comprising a plurality of strips of integrally connected closed fabric pockets each containing one helically coiled wire compression spring having its axis disposed transversely of the strip, and wherein each of the strips contains a single band of interconnected springs formed from a single length of wire into a plurality of interconnected helical coil springs. The springs of the bands may contain inserts such as foam cylinders or pocketed coil springs to impart differing degrees of firmness to different strips. Adjacent coil springs may be separated by multiple transverse lines of attachment in order to posturize the product.

Abstract: Spring sets each include a pair of coil springs joined together by a connecting wire and are encased in individual fabric pockets such that the connecting wire joining the coil springs spans an otherwise empty fabric pocket. A spring unit, mattress or the like includes a number of such pocketed spring sets with the connecting wire being alternately positioned near a top face or a bottom face of the spring unit. The pocketed coil spring unit can be used to form a mattress or other spring assembly of pocketed coil springs wherein every third pocket is left empty. The connecting wire spreads the load across the empty pocket and distributes the load to the adjacent springs. The absence of one-third of the springs that are normally in a mattress drastically reduces material costs without diminishing performance.

Abstract: A pocketed coil spring assembly for use in the manufacture of mattresses or cushions or the like comprising a plurality of strips of integrally connected closed fabric pockets each containing one helically coiled wire compression spring having its axis disposed transversely of the strip, and wherein each of the strips contains a single band of inter-connected springs formed from a single length of wire into a plurality of interconnected helical coil springs. The springs of the bands may contain inserts such as foam cylinders or pocketed coil springs to impart differing degrees of firmness to different strips. Adjacent coil springs may be separated by multiple transverse lines of attachment in order to posturize the product.

Abstract: Disclosed are pocketed upholstery springs in strip form characterized by placement of the closing seam midway between the ends of the springs of the strip, with the marginal flaps of the pocket strip fabric outwardly of the closing seam folded over as a two-ply belt and incorporated into the cross seams which define the pockets about the springs. Adjacent rows of such strips are joined together by tacking through their respective belts at the cross seams to form two-row modules for ease of mattress/cushion assembly, or to form full-size mattress/cushion constructions by joining row upon row.

Abstract: A seating suspension assembly provides efficiency in the manufacture of upholstered furniture such as chairs, sofas or the like. The preferred form of the invention comprises a pair of flexible, durable fabric straps having coil springs fixedly positioned therebetween. The fabric can be attached to a rigid wooden chair seat frame and the suspension assembly stapled or tacked thereto. The coil springs are thus suspended between the front and back of the frame. Upon upholstering, the suspension assembly provides a comfortable, crowned seat for the user. A method of forming the seating suspension assembly is also disclosed.

Abstract: A device for connecting springs together to define a support surface includes four arms each which extend in an outward radial direction from a center of the connecting device, the length of each arm defined by two sides extending in spaced relation to one another. Each arm includes a stiffening portion extending in a widthwise direction between the sides of the arm and extending from an end thereof towards the center of the connecting device only partially along the length of the arm. The straight sides of each arm have identical height dimensions and the stiffening portion has a lesser height than the height of the sides. The sides and the stiffening porting of each arm together define a planar surface of the arm and a finger portion extends from the end of the arm to define with the planar surface a U-shaped recess for gripping a top coil of a coil spring.

Abstract: A bed coil spring unit comprises a plurality of joined and interconnected spring cell units and a method of manufacturing the same. Each spring cell unit comprises a plurality of coil springs within long legs which long legs are used to form the coil springs. Each spring cell unit has a generally vertical axis. The coil springs which make up each spring cell unit are positioned symmetrically about the central axis. The plurality of coil springs in each spring cell unit conveniently numbers four(4).

Abstract: An innerspring assembly, such as for use in a mattress, comprises a plurality of coil springs defining upper and lower terminal convolutions and body portions therebetween. Adjacent coil springs are attached together at the body portions thereof with the terminal convolutions being unattached to one another, so that the terminal convolution can move independently of one another.

Abstract: A mattress inner spring core comprising a plurality of coil springs arranged in longitudinally extending columns and transversely extending rows. Each coil spring has an identically configured upper and lower end turn between which are a plurality of central convolutions defining a spring axis. Each end turn comprises first and second offset legs connected by a linear base web. A portion of a first leg of one end turn overlaps a portion of a second leg of an adjacent end turn in an overlapping region. Helical lacing wires encircle the legs of adjacent end turns to connect rows of springs. Each helical lacing wire has multiple revolutions encircling the overlapped legs of adjacent end turns with the same number of revolutions of the lacing wire encircling the overlapped portions of the legs and at least one complete revolution encircling a non-overlapped portion of the first and second legs of the end turns.

Abstract: A mattress spring core having a plurality of zones of differing firmnesses due to different characteristics of helical lacing connectors within the particular zones. The spring core has a plurality of identical coil springs arranged in side-by-side transversely extending rows and columns. The coil springs are connected together at the upper and lower ends of the springs with helical lacing connectors which encircle a portion of the upper and lower faces of the springs. The helical lacing connectors may be of a heavier gauge wire in one or more zones of the mattress spring core thus causing that particular zone to be of an increased firmness relative to the other zones of the mattress. Alternatively, the helical lacing connectors within a zone may comprise two or more co-axial lacing wires to impart greater strength or rigidity to one or more zones of the mattress.

Abstract: A spring core for a mattress consisting of a plurality of side-by-side rows of identically configured helical coil springs each made of a single piece of wire having a central portion of a first radius defining a central spring axis and terminating at opposing ends with unknotted upper and lower end turns disposed in planes substantially perpendicular to the spring axis. The springs are connected with each other at their upper and lower turns by connecting lacing wires. The upper and lower turns are each substantially U-shaped, having a longer relatively straight leg and a shorter arcuate leg located at the free end of each end turn, the legs connected to each other by a base web. The radius of the shorter arcuate leg is substantially less than the first radius of the central portion of each coil spring. All the coil springs are oriented in the same direction, except along an edge region of the spring core.

Abstract: Described is a spring core for a mattress, consisting of a multiplicity of identically shaped spiral springs with in each case two end rings lying diametrically opposite each other, which change to a spring coil part arranged centered between them, whereby the end rings are shaped approximately circular and consist essentially of two assembly legs, one transition leg and one additional leg and are opened on one side, whereby the leg lying opposite the respective open side of the upper or lower end ring is bent radially outward with respect to the longitudinal axis of the spring.

Abstract: A support device having a plurality of support units, each comprising a plurality of flexible, substantially vertical support columns, with the bottoms of the support columns attached at equidistant intervals to a base member and the tops of the support columns attached at equidistant intervals to a substantially perpendicular support platform. The support columns provide directional flexibility to the columns, upon compression, to provide a substantially uniform counter-force through a range of flexion of the support columns and corresponding downward deflection of said support device. Such uniform counter-force during compression simulates a fluid-like support system. The support columns may be comprised of a solid, synthetic foam such as high density polyurethane or springs made of metal or other material. The support units preferably are arranged in a matrix to provide collective support.