Patent Application
20080172799
The disclosure is in the general field of support structures, including flexible support structures.
Mattresses, and foundations (or “box springs”) for supporting sleeping mattresses have traditionally been constructed with the basic materials of textiles, including natural and synthetic materials for padding and comfort, and wood and steel components for structural support. For foundations, wood is used to construct the frame which supports an array of steel wire springs which elevate a grid or deck above the frame to form a reflexive support surface. The grid is also commonly made of steel wire which is welded or clipped together. Conventional mattresses use a wire form innerspring, made up of hundreds of helical or other shaped coils which are interconnected by wire or fabric. Layers of padding are positioned over the support ends of the springs of the innerspring, and the innerspring and padding is encapsulated with upholstery.
These basic constructions have now been in use for well over one hundred years, and although economical and practical, do not exploit the properties of modern materials which are advantageous for use in flexible support structures including bedding. The large number of components and required manual assembly increases to the cost of these conventional designs.
The present invention is a new type of flexible support system which utilizes a suspended flexible matrix. The flexible support system can be configured and used as a mattress or mattress foundation of any size. In one embodiment, a suspended flexible matrix support system is formed by a matrix of flexible members which are supported by a frame located at a perimeter of the flexible matrix. In one form, the frame is made of foam, such as extruded or molded or sculpted foam, configured to elevate a perimeter of the flexible matrix. Ends of the flexible members of the matrix may be capped or covered by channels which also contact a supporting surface of the frame. In one exemplary embodiment, the flexible matrix is suspended by a shelf structure formed at an interior perimeter of the frame, which elevates the flexible matrix above a surface or other support structure on which the frame rests. Because the frame is constructed of compressible and resilient foam material, the frame provides reflexive support in addition to the flexible matrix. The flexible members of the flexible matrix may be arranged both longitudinally and transversely with respect to the frame, and may be bonded together or fastened at interesting regions or points, or not. The configuration of the frame, including the cross-sectional shape of the frame members and the shape of the perimeter of the frame, may be varied by design. The height of the frame, and the height at which the frame supports or elevates the flexible matrix may also be varied by design. The material of the frame may also be varied according to desired characteristics. A preferred material is foam, and in particular extruded foam. The type and density of the foam can also be varied. Other representative materials for the frame include any type of engineered plastics made of entirely synthetic materials or combinations of synthetic and organic materials. The frame members may also perform other structural functions such as for attachment of other components of a bed or other support structure, such as legs, internal material layers and upholstery. Cavities may also be formed in the frame members to accommodate or house other components, sensors or electronics which are part of a flexible support system, and which also may be incorporated or integrated into the flexible matrix.
These and other aspects of the invention are further described herein as representative embodiments of the principles and concepts of the invention, as ultimately defined by the claims and not by the foregoing Summary of the Invention.
The frame members 12 can be made in any length to create any size or shape support surface, including any of the different conventional sizes of mattresses and mattress foundations. In one form, the frame members 12 are made of extruded foam, such as polyethylene which is extruded through a die with the desired cross-section shape, and which upon expansion thereafter assumes the same cross-sectional shape of the die opening on a larger scale. By the extrusion process, the polyethylene material forms an outer skin about the cross-section which surrounds the closed cells which form in the interior. The skin is thicker than the walls of the closed cells, and serves to hold the cross-sectional shape of the extruded part. The closed-cell geometric foam structure which is thus formed has excellent compressible and resilient support characteristics, and enough structural rigidity (from the combination of the closed cells and outer skin) to serve as a support structure, such as to elevate and support and suspend a flexible matrix as a support surface. The frame members 12 are thus compressible under loads applied directly or by the flexible matrix 20, and resilient, meaning that they return to the uncompressed configuration when applied loads are removed.
Given the excellent support characteristics of the frame members 12 when fabricated in this manner, the extent to which the frame members 12 may underlie the flexible matrix 20, e.g. the width of shelf 123, can be varied by design. For example, the height of the frame member 12 and resulting elevation of the shelf 123 on which edges of the flexible matrix 20 rests can be specified according to the overall design height and width of the flexible matrix support system 10.
The flexible matrix 20 is, in one representative form, made from intersecting elongate flexible members (also referred to herein as “flexible members”) 22 and 24 of any suitable flexible material. Flexible members 22 are arranged parallel in a first direction, such as longitudinally, aligned with the length of frame 12. In this arrangement the flexible members 22 are also referred to as “longitudinal members”. Flexible members 24 are arranged generally transversely and perpendicular to members 22 and span across a width of frame 12. In this arrangement the flexible members 24 are also referred to as “transverse members”. The arrangement and intersection of the flexible members 22 and 24 does not have to be orthogonal as shown, but may be in any manner which creates a flexible support matrix capable of supporting additional materials and different types and sizes of loads. The flexible members 22, 24 are also alternatively referred to as either the “first group” or “second group” of flexible members.
The flexible members 22, 24 can be made of any type of material which provides adequate strength and a desired degree of flexibility, primarily in the vertical dimension, normal to the plane in which the flexible matrix 20 lies in an unloaded state. A general design criteria is that deflection of the matrix 20 at any one point when under a load not exceed the elevation of the matrix 20 above the bottom surface 122 of the frame members 12. In the embodiment shown, the flexible members 22 are underlying flexible members 24. In this case, the stiffness or bending modulus of the underlying flexible members 22 can be designed to be greater than that of overlying flexible members 24 in order to augment the overall stiffness of the flexible matrix 20. Alternatively, the stiffness or bending modulus of any of the flexible members of the flexible matrix 20 can be designed or selected to tune the flexibility of the matrix 20 in any particular region.
In one form, the flexible members 22, 24 can be made as molded parts or pultrusions of any suitable polymeric material, including but not limited to the classes of polypropylene, polyethylene, nylon or ABS and with fiber reinforcement. For example, glass or synthetic fibers may be integrated with epoxy or vinyl or polyesters, high density plastic such as polyethylene, high density plastic foam, encapsulated steel or steel alloys, or any other materials and combinations of materials which have the desired flex modulus and cycle strength when formed in the described shapes of the flexible members 22, 24. When made of fiber-reinforced composite material, the flexible members may be compound molded or compression molded into the elongate shapes, or by a pultrusion process, wherein continuous strands of fiber such as fiberglass or other material (which may constitute anywhere from 20% to 80% of the volume of the finished product) are saturated with a resin system by pulling through a vat of epoxy or vinyl ester. The combined materials are then compression molded into the desired shapes, such as any of the various described shapes of the flexible members 22, 24 and variations thereof.
As shown in
As further shown in
One or more internal or external components 30 may be provided within frame 12 and above or below the flexible matrix 20, such as a foam pad within the perimeter defined by the frame members 12 and underneath the flexible matrix, as shown in phantom in
As shown in
External components include exterior layers of padding or cushioning, “active layers” such as air or water chambers or bladders, sensors such as in the form of smart cloth or other instrumented materials or devices, heating or cooling elements, and insulating and upholstery materials.
