Patent Publication Number: US-2011072587-A1

Title: Foam cushion having reduced cross-section area foam profiles forming hollow portion(s) for deformation

Description:
PRIORITY CLAIMS 
     The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/246,772, filed Sep. 29, 2009, titled “CLOSE CELL FOAM CUSHION,” which is incorporated herein by reference in its entirety. 
     The present application also claims priority to U.S. Provisional Patent Application Ser. No. 61/293,289, filed Jan. 8, 2010, titled “CLOSE CELL FOAM CUSHION,” which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     1. Field of the Disclosure 
     The technology of the disclosure relates to cushioning, which may be used, for example, in cushioning applications such as mattresses, seats, foot support, back support, and protection pads. 
     2. Technical Background 
     Cushions and materials providing cushioning are used in numerous environments and applications, for example, in the home, hotels, transportation, hospitals, sport facilities, etc. In terms of cushion material and structure, metal spring and open cell polyurethane foam planks have been popularly employed. Convoluted open cell polyurethane foam, latex foam, and inversely convoluted foam cushion have also been employed in lieu of using metal springs. In comparison with open cell foam, close cell foam at the same density can show higher compression modulus. In other words, one may use much lighter weight close cell foam to reach similar firmness of open cell foam. This can reduce carbon release of a cushioning product, providing environmental protection and energy savings. 
     Open channel crossing a foam cushion has been widely used to improve cushioning performance. Cushion surfaces may have different indentation patterns for better touch, feel and appearance. In addition, a cushion can be made from various types of repeating units, such as half moon shapes and big bubbles as examples. However, in these examples, the cushion does not easy bend or curl for transportation or storage. One could provide a cushion pad that is more easily bent or curled by providing a thin cushion pad in which a foam pad is indented with spanned folding lines to provide bend lines for easier bending and curling of the pad. However, it may be desirable to provide a thicker cushion that can be easily bent or folded for transportation while still retaining the cushioning performance provided by the indentation patterns provided in the cushioning surface. 
     SUMMARY OF THE DETAILED DESCRIPTION 
     Embodiments disclosed in the detailed description include cushions, which may be used in mattresses, bedding, seats, and mats as non-limiting examples. Non-limiting features of these cushions are to effectively support a compression force with much less usage of material, to adapt to large deformations without bottoming out as seen for some spring coils, to curl up for easy shipping and storage, and/or to have light weight and good buoyancy. 
     In this regard, in one embodiment, a cushion is comprised of a plurality of foam profiles. Each of the plurality of foam profiles has a top surface and a bottom surface, and a geometry of reduced cross-section area from the top surface to the bottom surface in a vertical projection. The plurality of foam profiles are arranged such that the top surfaces of the plurality of foam profiles are disposed in or substantially in a first plane, and the bottom surfaces of the plurality of foam profiles are disposed in or substantially in a second plane parallel or substantially parallel to the first plane. In this manner, hollow portions can be formed between adjacent foam profiles. At least one sheet of material is affixed to at least one of the top surface and the bottom surface of the plurality of foam profiles. The sheet of material assists to maintain the integrity of the cushion and to distribute an imposed force to the plurality of foam profiles. When a compression force is imposed on the cushion, the hollow portions allow the plurality of foam profiles to change their shapes to adapt to the deformation. As the compression force is removed, the plurality of foam profiles can return to their original shapes. Further, by providing the hollow portions, the cushion can more easily be rolled or wrapped for transport or storage. 
     In another embodiment, a method of providing a cushion is provided. The method comprises providing a plurality of foam profiles each having a top surface and a bottom surface, and a geometry of reduced cross-section area from the top surface to the bottom surface in a vertical projection. The method also comprises arranging the plurality of foam profiles such that the top surfaces of the plurality of foam profiles are disposed in or substantially in a first plane, and the bottom of the plurality of foam profiles are disposed in or substantially in a second plane parallel or substantially parallel to the first plane. The method also comprises affixing at least one sheet of material to at least one of the top surface and the bottom surface of the plurality of foam profiles. 
     Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description that follows, the claims, as well as the appended drawings. 
     For example, wherein the plurality of foam profiles can be comprised of foamed material comprised from the group consisting of polypropylene, polypropylene copolymer, polystyrene, polyethylene, ethylene vinyl acetate (EVA), polyolefin, metallocene catalyzed low density polyethylene, thermoplastic olefin (TPO), thermoplastic polyester, thermoplastic vulcanizates (TPVs), polyvinyl chlorides (PVCs), chlorinated polyethylene, styrene block copolymers, ethylene methyl acrylates (EMAs), ethylene butyl acrylates (EBAs), polyurethane, natural rubber, synthetic rubber, latex, silicone, ethylene propylene diene Monomer (M-class) rubber (EPDM), isoprene, chloroprene, neoprene, melamine-formaldehyde, and polyester. The foam can include closed cells, open cells, or a combination of both. Any density of the foam profiles is possible. Different zones of firmness can be provided in the cushion. The sheet of material can be comprised of either a woven or non-woven sheet of material. The cross-section shape of the plurality of foam profiles can be provided in a variety of shapes. Edges pieces can be disposed on ends of the plurality of foam profiles for the cushion. The plurality of foam profiles can include hollow sections that may or may not include filler material. The cushion can be used in any application desired, including but not limited to a mattress, a bed, a seat, furniture, a mat, a beach mat, a camping mat, an athletic mat, padding, and a protection pad. 
     It is to be understood that both the foregoing general description and the following detailed description present embodiments, and are intended to provide an overview or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  illustrates a side perspective view of an exemplary cushion comprised of a plurality of adjacent exemplary foam profiles having a geometry of reduced cross-section area from top to bottom in a vertical projection, with sheets affixed to the foam profiles; 
         FIG. 2A  illustrates a side view of an exemplary foam profile in  FIG. 1  in an uncompressed state; 
         FIG. 2B  illustrates a side view of an exemplary foam profile in  FIG. 1  in a compressed state; 
         FIGS. 3A-3F  illustrate side views of exemplary alternative foam profiles that can be employed in a cushion, including the cushion in  FIG. 1  as an example, and according to the embodiments disclosed herein; 
         FIGS. 4A-4C  illustrate side views of exemplary foam profiles for building up the edge portion of a cushion, including the cushion in  FIG. 1  as an example, and according to the embodiments disclosed herein; 
         FIG. 5  illustrates a side view of the cushion of  FIG. 1  partially rolled up; 
         FIGS. 6A-6C  illustrate exemplary filler material disposed in a hollow portion of the foam profile in the cushion of  FIG. 1 ; 
         FIGS. 6D-6F  illustrate side views of exemplary filler material disposed in a hollow portion of an alternative foam profile that may be provided in a cushion, including the cushion of  FIG. 1  as an example; 
         FIG. 7  illustrates a top view of a cushion comprised of a plurality of adjacent exemplary foam profiles having a geometry of reduced cross-section area from top to bottom in a vertical projection, with sheets affixed to the foam profiles, which also employs end foam profiles on ends to provide intensified firmness at edge portions of the cushion; 
         FIG. 8  illustrates a side perspective view of a cushion comprised of a plurality of adjacent exemplary foam profiles having a geometry of reduced cross-section area from top to bottom in a vertical projection, with sheets affixed to the foam profiles, wherein the foam profiles are melted down on a top surface before a sheet is applied thereto to create pattern of islands and grooves in the cushion; 
         FIG. 9  illustrates a side perspective view of a cushion comprised of a plurality of adjacent exemplary foam profiles having a geometry of reduced cross-section area from top to bottom in a vertical projection, and further comprising an open cell layer disposed on top of the foam profiles with strips of re-closable fastener disposed on the bottom of the foam profiles; 
         FIG. 10  illustrates a side perspective view of a cushion comprised of a plurality of adjacent exemplary foam profiles comprised of multiple pieces of long and specially shaped close cell foam profiles having a geometry of reduced cross-section area from top to bottom in a vertical projection; 
         FIG. 11  illustrates a side view of the foam profile provided in the cushion of  FIG. 10 ; and 
         FIGS. 12A and 12B  illustrate perspective and side views, respectively, of the foam profile provided in the cushion of  FIG. 10  with optional cuts disposed in the foam profile. 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments set forth below represent the necessary information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the embodiments and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims. 
     Embodiments disclosed in the detailed description include cushions, which may be used in mattresses, bedding, seats, and mats as non-limiting examples. Non-limiting features of these cushions are to effectively support a compression force with much less usage of material, to adapt to large deformations without bottoming out as seen for some spring coils, to curl up for easy shipping and storage, and/or to have light weight and good buoyancy. 
     In this regard, in one embodiment, a cushion is comprised of a plurality of foam profiles. Each of the plurality of foam profiles has a top surface and a bottom surface, and a geometry of reduced cross-section area from the top surface to the bottom surface in a vertical projection. The plurality of foam profiles are arranged such that the top surfaces of the plurality of foam profiles are disposed in or substantially in a first plane, and the bottom surfaces of the plurality of foam profiles are disposed in or substantially in a second plane parallel or substantially parallel to the first plane. In this manner, hollow portions can be formed between adjacent foam profiles. At least one sheet of material is affixed to at least one of the top surface and the bottom surface of the plurality of foam profiles. The sheet of material assists to maintain the integrity of the cushion and to distribute an imposed force to the plurality of foam profiles. When a compression force is imposed on the cushion, the hollow portions allow the plurality of foam profiles to change their shapes to adapt to the deformation. As the compression force is removed, the plurality of foam profiles can return to their original shapes. Further, by providing the hollow portions, the cushion can more easily be rolled or wrapped for transport or storage. 
       FIG. 1  illustrates a side perspective view of an exemplary cushion  11  comprised of a plurality of adjacent exemplary foam profiles  12  having a geometry of reduced cross-section area from top to bottom in a vertical projection, with sheets  13  affixed to the plurality of foam profiles  12 . As examples only, the cushion  11  may be used in any application desired, including but not limited to a mattress, a bed, a seat, furniture, a mat, a beach mat, a camping mat, an athletic mat, padding, and a protection pad. In this example, the plurality of foam profiles  12  includes multiple pieces of hollow, long, and specially shaped close cell foam. However, the plurality of foam profiles  12  could also be open cell, or a combination of both open and close cells. 
     In this embodiment, the plurality of foam profiles  12  each have a top surface  14  and a bottom surface or edge  15 , and a geometry of reduced cross-section area from the top surface  14  to the bottom surface  15  in a vertical projection. In this example, the cross-section outskirt of plurality of foam profiles  12  is a triangle, which may be an isosceles triangle, but other geometries are possible that provide this reduced cross-section area feature. Non-limiting examples include circles, ellipses, other triangles, rectangles, trapezoids, and other polygons that have more than four (4) sides. In this example, each of the plurality of foam profiles  12  also contains a hollow portion  17  to allow for deformation when a force is imparted thereon, as described below in more detail. 
     In this embodiment, the plurality of foam profiles  12  are disposed between two sheets  13 . The sheets  13  can serve to maintain the integrity of the cushion  11  when a force is imparted on the cushion  11 . The sheets  13  are comprised of a material or materials. The plurality of foam profiles  12  are arranged such that the top surfaces  14  are disposed in or substantially in a first plane P 1 , and the bottom surfaces  15  are disposed in or substantially in a second plane P 2  parallel or substantially parallel to the first plane P 1 . The sheets  13  are affixed to the plurality of foam profiles  12  from its top surface  14  and bottom surface  15 . In this manner, as discussed in more detail below, voids V are created between adjacent foam profiles  12  at the top surfaces  15  of the plurality of foam profiles  12  due to the reduced cross-section area disposed in the plurality of foam profiles  12  to allow for easy bending and rolling of the cushion  11 . 
     The sheets  13  may be made from any material desired, and may be woven or non-woven. The sheets  13  may be affixed to the plurality of foam profiles  12  using an affixation means comprised from the group consisting of thermal welding and ultrasonic welding. Multiple levels, such as three (3) or more layers of sheets enclosing two (2) or more layers of foam profiles  12 , may be provided. The sheets  13  could be pieced together instead of providing the sheets  13  as one single piece of material. The sheets  13  could be made of materials that are flexible or materials that do not stretch. 
     An edge piece  16  is a long rectangular piece of foam used to build an edge portion of cushion  11 , and it is also bonded to non-woven sheets  13 . There is a much larger bonding area between the plurality of foam profiles  12  and the non-woven sheet  13  on a top surface of the cushion  11  than that on a bottom surface of the cushion  11 . Because of strong bonding of the plurality of foam profiles  12  as well as the edge pieces  16  with the non-woven sheets  13 , the cushion  11  has good integrity. 
     As examples, the plurality of foam profiles  12  can be comprised of foamed material comprised from the group consisting of polypropylene, polypropylene copolymer, polystyrene, polyethylene, ethylene vinyl acetate (EVA), polyolefin, metallocene catalyzed low density polyethylene, thermoplastic olefin (TPO), thermoplastic polyester, thermoplastic vulcanizates (TPVs), polyvinyl chlorides (PVCs), chlorinated polyethylene, styrene block copolymers, ethylene methyl acrylates (EMAs), ethylene butyl acrylates (EBAs), polyurethane, natural rubber, synthetic rubber, latex, silicone, ethylene propylene diene Monomer (M-class) rubber (EPDM), isoprene, chloroprene, neoprene, melamine-formaldehyde, and polyester. The plurality of foam profiles  12  can include closed cells, open cells, or a combination of both. Any density of the plurality of foam profiles  12  is possible. The plurality of foam profiles  12  could be separated along the extrusion direction like blocks to provide independent movement in the extrusion direction. 
     The plurality of foam profiles  12  can be made of various foam materials such as cross-linked or non-cross-linked polyolefin, rubber, or other polymers which have a glass transition temperature below room temperature around 25 degrees C., as examples. The plurality of foam profiles  12  may have a density, for example, in a range of 8 kg/m 3  to 100 kg/m 3 , preferably 16 kg/m 3  to 48 kg/m 3 . The plurality of foam profiles  12  may have a cell size in a range of 0.01 mm to 10 mm, preferably 0.3 mm to 3 mm, as examples. The plurality of foam profiles  12  may have a close cell content of more than 80% as an example. The plurality of foam profiles  12  may also contain various additives such as a flame retardant, a smoke suppressant, an antimicrobial agent, a fragrance, a color, etc., as examples. 
     Also, because the sheet  13  is attached to the bottom surface  15  of the plurality of foam profiles  12 , when a compression force is imposed on the cushion  11 , the plurality of foam profiles  12  are deformed while the integrity of the cushion  11  is maintained. The sheet  13  also plays a role in keeping each individual foam profile  12  maintained into a proper position in the cushion  11 . In this regard,  FIG. 2A  illustrates a side view of a foam profile  12  in  FIG. 1  in an uncompressed state.  FIG. 2B  illustrates a side view of a foam profile  12  in  FIG. 1  in a compressed state. More particularly,  FIGS. 2A and 2B  show schematically a change in cross-section of the plurality of foam profiles  12  before and after compression (e.g., 50% compression). Because the hollow portion  17  is disposed in the foam profile  12 , the foam profile  12  is also capable of adapting to large deformation. Once a compression force is removed, the foam profile  12  can return to its original shape. 
     There could be many alternative shapes for the plurality of foam profiles  12 . In this regard,  FIGS. 3A-3F  illustrate side views of exemplary alternative foam profiles  12  that can be employed in a cushion, including the cushion  11  in  FIG. 1  as an example. As shown in  FIGS. 3A and 3B , hollow foam profiles  10  and  18  can have concave and convex side surfaces. A hollow foam profile  19  can have an outskirt of isosceles trapezoid and inner elliptical channel as shown in  FIG. 3C . A hollow foam profile  20  can represent an isosceles trapezoid with arc bottom as shown in  FIG. 3D . The cross-section of a hollow foam profile  22  can have grooves on its top surface, as shown in  FIG. 3E , to have better air convection on the profile surface. In order to speed up air flow in and out of a hollow foam profile, holes  21  can be drilled through the hollow foam profile wall, as shown in  FIG. 3F . 
       FIGS. 4A-4C  illustrate side views of exemplary foam profiles for building up the edge portion of a cushion, including the cushion  11  in  FIG. 1  as an example. The cushion  11  can have the rectangular edge piece  16 , as shown in  FIGS. 1 and 4A  as an example. As alternatives, a solid right angle trapezoid foam profile  23  and a hollow right angle trapezoid foam profile  24  can be used as shown in  FIGS. 4B and 4C , as another example. 
       FIG. 5  illustrates a side view of the cushion  11  of  FIG. 1  partially rolled up. Since the sheet  13  is soft and flexible, the cushion  11  can be bent as shown in  FIG. 5 . Also, the plurality of foam profiles  12  in this example are arranged in parallel and distanced from each other with a space or void V between them, which allows easy bending and curling of the cushion  11  as well. When the cushion  11  is bent or curled, the voids V formed in the cushion  11  between adjacent foam profiles  12  provide for the ability for the cushion  11  to be easily bent or curled. The voids V between the foam profiles  12  in the cushion  11  are reduced and eventually closed if the adjacent foam profiles  12  are brought together during bending or curling of the cushion  11 . The greater the void V between adjacent foam profiles  12 , the more the cushion  11  can be rolled with less radius. 
     It may also be desired to have greater firmness for the edge portion of the cushion  11  than the middle portion of the cushion  11 . For example, in a mattress application, this may assist in preventing a person from falling off the mattress. Firmness in the edge portion can be intensified by inserting a short piece of solid foam into the end of a corresponding hollow foam profile. In this regard,  FIG. 6A  illustrates the foam profile  12  with the hollow portion  17  disposed therein.  FIGS. 6B and 6C  illustrate exemplary filler material  25  disposed in the hollow portion  17  of the foam profile  12  in the cushion  11  of  FIG. 1 .  FIGS. 6D-6F  illustrate side views of exemplary filler material  27  disposed in a hollow portion  40  of the hollow foam profile  19  that may be provided in a cushion, including the cushion  11  of  FIG. 1  as an example. For example, as illustrated in  FIGS. 6A-6C , the filter material  25  may be a triangle-shaped foam insert that can be put in the end of the hollow portion  17  of the foam profile  12  to form a combined profile  26 . As another example, as illustrated in  FIGS. 6D-6F , the filler material  27  in the form of an elliptical-shaped foam insert can be put in the end of the hollow foam profile  19  to form a combined profile  28 . 
       FIG. 7  illustrates a top view of the cushion  11  of  FIG. 1  which employs solid right angle trapezoid foam profiles  23  on ends of the cushion  11  to provide intensified firmness at edge portions of the cushion  11 .  FIG. 8  illustrates a side perspective view of the cushion  11  of  FIG. 1  comprised of the plurality of adjacent exemplary foam profiles  12  melting down on the top surface  14  in a desired pattern, such as having islands  29  and grooves  30 . The resulting cushion  11  may have a more rugged feel and appearance. 
       FIG. 9  illustrates a side perspective view of the cushion  11  of  FIG. 1 , modified by adding an open cell foam layer  31  on the top of the cushion  11 . On the bottom surface of the cushion  11 , strips of re-closable plastic fasteners can be used along the edge of the cushion  11  to lock the position of the bottom non-woven sheet  13  to a supporting surface, specifically using a pair of fasteners  32 , which may be re-closeable, in a lateral direction and a pair of fasteners  33  in a longitudinal direction, as shown in  FIG. 9 . Matching parts of the pairs of fasteners  32 ,  33  on the supporting surface underneath the cushion  11  are not shown in  FIG. 9 . 
       FIG. 10  illustrates a side perspective view of a cushion  34  composed of multiple pieces of long and specially shaped close cell foam profiles  35  between two non-woven sheets  13 . Each of the foam profiles  35  has geometry of reduced cross-section area from top to bottom in terms of its vertical projection, as shown in  FIG. 11 . In this embodiment, the foam profile  35  contains an opening  41 . The non-woven sheets  13  are affixed to the foam profile  35  to cover the top and bottom of the foam profiles  35 . All of the pieces of the foam profiles  35  are in parallel and distanced from each other with a small space. Because of the strong bonding of the foam profiles  35  with the non-woven sheets  13 , the cushion  34  has good integrity. Since the non-woven sheets  13  are soft and flexible, the cushion  34  can be bent. When a compression force is imposed on the cushion  34 , the foam profile  35  changes its shape to adapt to a large deformation. The non-woven sheets  13  play a role of keeping each individual foam profile  35  locked in a proper position in the cushion  34 . Once a compression force is removed, the foam profiles  35  return to their original shapes. 
       FIGS. 12A and 12B  illustrate perspective and side views, respectively, of a foam profile  35  employed in the cushion  34  of  FIG. 10  with optional cuts  42  disposed therein. Providing the optional cuts  42  may serve to provide a desired cushioning effect and may also reduce the weight of the cushion  34 . With the optional multiple cuts  42  cut from the bottom to trim out a portion of the foam profile  35 , the foam profile  35  becomes foam profile  36 , as shown in  FIGS. 12A and 12B . 
     Many modifications and other embodiments of the embodiments set forth herein will come to mind to one skilled in the art to which the embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the description and claims are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. It is intended that the embodiments cover the modifications and variations of the embodiments provided they come within the scope of the appended claims and their equivalents. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.