Patent Publication Number: US-2009222985-A1

Title: Stackable bedding foundation having pocketed topper

Description:
BACKGROUND OF THE INVENTION  
     This invention relates generally to bedding, and more particularly to a nestably stackable bedding foundation. 
     Bedding foundations or so-called box spring assemblies generally include spaced border wires between which coil or bent wire spring modules are located. As thus manufactured, these box spring assemblies are bulky and shipping them to the manufacturer for application of padding and covering thereto is costly because of space requirements. To reduce the space requirements, it is customary to compress the assemblies to reduce their individual thicknesses and to tie them in their compressed state. This involves using presses and ties which are expensive, and the extra operations of pressing and tying the assemblies also adds to their manufacturing cost. At the delivery end, the manufacturer must cut and discard the ties before applying the covering. These additional material and handling expenses increase the end cost of box spring assemblies. 
     Box spring assemblies or bedding foundations by their very nature are intended to provide a stable, firm support foundation for mattresses or other bedding placed on top thereof. Toward that end, the spring modules commonly used in the box spring assemblies are relatively firm and provide little cushioning capability. Some users find that such bedding foundations are too rigid for their liking; they would prefer a softer bedding foundation or box spring. It would be desirable for such persons to have a bedding foundation with a cushioning layer to: 1) improve mattress support; 2) improve the lifespan of the mattress; and 3) increase the user&#39;s comfort. 
     Therefore, a bedding foundation having a cushioning layer that can be stacked for shipping without having to compress and tie the assembly would be desirable. 
     Additionally, a bedding foundation having a cushioning layer, which is relatively simple to manufacture, and which may substitute for a traditional box spring assembly having no cushioning layer would also be desirable. 
     SUMMARY OF THE INVENTION  
     This invention provides a solution to these and other problems in the art. In one embodiment, this invention is a bedding foundation having nestably stackable components for use in place of the traditional box spring assembly. Bedding foundations having nestably stackable components are disclosed in U.S. Pat. Nos. 5,052,064 and 7,237,282, both of which are fully incorporated herein. This bedding foundation includes a rectangular base comprising a rectangular base frame and a plurality of intermediate transverse slats. 
     The bedding foundation further comprises a spring assembly fixedly attached atop the base. The spring assembly comprises a generally rectangular border wire having two parallel sides and two parallel ends and a plurality of transversely-spaced, parallel, and longitudinally-extending support wires parallel to the border wire sides and with ends connected to the border wire ends. These support wires are generally corrugated along their lengths, having peaks and valleys with the peaks being generally coplanar with the plane defined by the border wire and the valleys being displaced beneath and intermediate of the peaks. Longitudinally-spaced, parallel and transversely-extending upper connector wires are parallel to the border wire ends, having ends connected to the border wire sides and connected along their lengths to the flattened distal portions of the peaks of the support wires. 
     The longitudinal voids between the peaks of the support wires are of a greater dimension than the valleys of the support wires. This configuration enables one bedding foundation assembly of this invention to be nestedly stacked atop a second assembly since the support wire valleys of the first assembly fit into the voids between the peaks of the support wires of the second assembly. Such a nested and stacked arrangement results in a total height dimension which is less than the sum of the individual assembly height dimensions. 
     The bedding foundation assembly further comprises a cushioning pad overlaying the spring assembly. The cushioning pad may be hog ringed or secured in any desired manner to the spring assembly. 
     A border or edge railing is secured to the cushioning pad around the perimeter of the cushioning pad with adhesive or in any other suitable manner. This border or edge railing is preferably made of foam but may be made of any material. This border or edge railing provides containment for a pocketed spring assembly which resides inside the border or railing. The pocketed spring assembly rests on top of the cushioning pad and may be secured to the cushioning pad. The pocketed spring assembly comprises strings of individually pocketed coil springs, as is conventional in the art. The strings of springs are joined together and may extend either longitudinally (from head to foot) or transversely (from side to side). 
     One advantage of this invention is that it provides a bedding foundation assembly having a cushioning layer, the components of which may be independently shipped, some of the component being tightly nested, compacted and shipped in a minimum of space to an assembly destination, thereby reducing the ultimate cost of the unit to the assembler. 
     Yet another advantage of this invention is avoiding the need for costly presses and ties necessary to compress a conventional box spring assembly for transportation. 
     A further advantage of this invention is that bedding foundation assemblies may be rapidly unloaded without the time consuming and labor intensive tasks of clipping and discarding the tie wires used to hold conventional box spring assemblies in a compressed state. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
       The objectives and features of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG.1  is a perspective view, partially broken away, of a bedding foundation according to one embodiment of this invention; 
         FIG. 2  is an enlarged perspective view, partially broken away, of a portion of the bedding foundation of  FIG. 1 ; 
         FIG. 3  is a top plan view, partially broken away, of the bedding foundation of  FIG. 1 ; 
         FIG. 3A  is a top plan view, partially broken away, of an alternative embodiment of bedding foundation in accordance with the invention; 
         FIG. 4  is a cross sectional view, partially broken away, of the bedding foundation of  FIG. 1 ; 
         FIG. 5  is a partially exploded view of the bedding foundation of  FIG. 1 ; and 
         FIG. 6  is a view taken along the line  6 - 6  of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     Referring first to  FIG. 1 , a bedding foundation or box spring  10  according to one embodiment of this invention is illustrated. The bedding foundation has a longitudinal dimension or length L defined as the distance between end surfaces  12  of the foundation; a transverse dimension or width W defined as the distance between side surfaces  14  of the foundation and a height H defined as the distance between upper and lower surfaces  16 ,  18 , respectively, of the foundation  10 . 
     The foundation  10  has a generally rectangular base  20  including a generally rectangular base frame  22  on which transverse slats  24  are attached. The base  20  is preferably made of wood but may be made of any suitable material such as plastic. 
     A nestably stackable spring assembly or wire core  26  is atop the base  12  and particularly the transverse slats  24 . A cushioning pad  28  overlies the nestably stackable spring assembly  26 , a border  30  is fixedly secured to the perimeter of the cushioning pad  28 , a pocketed spring assembly  32  located inside the border  30  and a fabric covering  34  surrounds the base  20 , nestably stackable spring assembly  26 , cushioning pad  28 , border  30  and pocketed spring assembly  32 . 
     The nestably stackable spring assembly  26  includes a rectangular steel border wire  36  having two parallel sides  38  and two parallel ends  40 . In the illustrated embodiment, the parallel sides  38  are longer than the parallel ends  40 . However, in a square foundation, the sides  38  and ends  40  of border wire  36  would be the same length. 
     The nestably stackable spring assembly  26  further comprises a plurality of transversely-spaced, parallel, and longitudinally-extending steel support wires  42  parallel to the border wire sides  38 . Each of these support wires  42  has ends  44  which are crimped around the ends  40  of the border wire  36 . These support wires  42  are formed so as to be generally corrugatedly-shaped along their lengths, having peaks  46  and valleys  48 . These peaks  46  and valleys  48  are flattened at their respective distal portions  50  and  52 , respectively. The adjacent distal portions  50 ,  52  are joined together by connecting portions  54  of the support wire  42 . As disclosed in U.S. Pat. No. 7,237,282, which is fully incorporated by reference herein, according to various embodiments of this invention, these flattened valley distal portions  52  may be twisted relative to the plane defined by the flattened peak distal portions  50  and vertically spaced beneath and intermediate of the flattened peak distal portions  50 . 
     The nestably stackable spring assembly  26  further comprises longitudinally-spaced, parallel, and transversely-extending steel upper connector wires  56  which extend parallel to the border wire ends  40  and have ends  58  which are crimped around the border wire sides  38 . These upper connector wires  56  are welded intermediate of their ends  58  along their lengths at  60  to the flattened peak distal portions  50  of the support wires  42 . 
     The support wires  42  have flattened distal peak portions  50  and flattened distal valley portions  52 , with the support wire ends  44  being crimped around the border wire ends  40 . In the illustrated embodiment, three upper connector wires  56  per flattened distal peak portion  50  are illustrated. In other embodiments, any number of upper connector wires  56  may be welded or secured to each flattened distal peak portion  50 . The distal valley portions  52  of the support wires  42  are stapled with staples  62  to the transverse slats  24  of base  20 . However, the distal valley portions  52  of the support wires  42  may be otherwise secured to the transverse slats  24  of base  20 . 
     If desired, additional steel end wires (not shown) may be added either before or after the stackable spring assembly  26  has reached its final assembly destination. These end wires have spaced ends which are crimped around the border wire  36  and the endmost upper connector wire  56 , respectively. These end wires provide additional stiffness to the stackable spring assembly  26  in an edge most location of the ends of the assembly  26  so as to prevent the end border wires from deflecting and being permanently distorted when a person sits on the end of a bed of which the foundation forms a part. Such steel end wires are shown in U.S. Pat. No. 5,361,434, which is hereby incorporated by reference in its entirety. 
     Referring again to  FIGS. 1 and 2 , continuous longitudinal wires  64  are included in the nestably stackable spring assembly  26 . These longitudinal wires  64  have their ends  66  crimped around the border wire ends  40  and pass over upper connector wires  56 . These longitudinal wires  64  may be welded along their lengths to the upper connector wires  56  at locations  68  as desired. In the illustrated bedding foundation  10 , two longitudinal wires  64  are illustrated as being part of the nestably stackable spring assembly  26 . However, any number of longitudinal wires  64  may be incorporated into the nestably stackable spring assembly  26 . 
     As best shown in  FIGS. 2 and 5 , the bedding foundation  10  further comprises a cushioning pad  28  overlaying the nestably stackable spring assembly  26 . The cushioning pad  28  is secured to the border wire  36  with hog rings  70 . The cushioning pad  28  is preferably made of polyethylene foam or shredded fabric, but may be made of any desirable material. 
     As shown in  FIG. 5 , the bedding foundation  10  further comprises a generally rectangular border  72  having opposed end portions  74  and opposed side portions  76 , the border  72  being secured to the cushioning pad  28  around the perimeter of the cushioning pad  28 . As shown in  FIG. 3 , the border  72  has a width W 1 . Although the border  72  is illustrated as being one piece of material, it may comprises multiple pieces joined together. The border  72  is preferably adhesively secured to the upper surface of the cushioning pad  28  but may be secured to the cushioning pad  28  in any known manner. The border  72  is preferably made of polyethylene or polyurethane foam, but may be made of any desirable material. Although the border  72  may be any desired height, it is preferably between one and a half inches and four inches tall, the same height as the pocketed spring assembly  32 . The border functions as an edge reinforcement and increases the edge firmness of the bedding foundation  10 . 
     As best shown in  FIGS. 3 ,  5  and  6 , the bedding foundation  10  further comprises pocketed spring assembly  32  for supporting a mattress (not shown) and providing an additional cushioning layer to the bedding foundation  10 . Pocketed spring assembly  32  is made to fit inside generally rectangular border  72 . The pocketed spring assembly  32  may or may not be secured to the upper surface of the cushioning pad  28 . As shown in the drawings, pocketed spring assembly  32  includes a plurality of longitudinally extending strings of springs  80  joined together as shown in  FIG. 5 . Adjacent strings of springs  80  are preferably glued together but be joined to each other using any known technology such as ultrasonic welding. 
       FIG. 6  illustrates a string of springs  80  having an upper surface  82  and a bottom or lower surface  84 , the distance between which defines the height H 1  of the string of springs  80 . Each string of springs  80  comprises a row of interconnected fabric pockets  86 , each fabric pocket  86  containing a coil spring  88 . As shown in  FIG. 6 , each coil spring  88  has an upper end turn  90 , a lower end turn  92  and a plurality of central convolutions  94  between the end turns  90 ,  92 . Although one configuration of coil spring is shown, any other spring, whether a coil spring or not, may be used with the present invention. 
     Preferably, only one piece of fabric is used to form a string of springs  80 , the piece of fabric being folded over onto itself around the coil springs  88  to create a first ply  96  and a second ply  98 . As illustrated in  FIG. 6 , the first ply  96  is behind the second ply  98 . As is known in the art, opposite sides or plies of the fabric are sewn, welded or otherwise secured together to create a pair of outermost seams  1   00 , a plurality of parallel internal seams  102 , and a longitudinal top seam  104 . Although seams  100 ,  102  and  104  are illustrated as a plurality of spaced, linear segments  106 , they may comprise continuous lines or a series of dots or other arrangement without departing from the spirit of this document. 
     In one embodiment, the height Hi of the strings of springs  80  is approximately one inch. Therefore, the height of the pocketed spring assembly  32  is approximately one inch. However, the strings of springs and pocketed spring assembly may be any desired height. Heights which have proven satisfactory are between one and a half to four inches. 
     The spring assembly  26  of bedding foundation  10  is generally manufactured by a supplier, who then ships it to an assembler. The assembler adds to the spring assembly  26  the wooden base  20 , cushioning pad  28 , secures the border  30  to the cushioning pad  28 , inserts the pocketed spring assembly  32  into the opening in the border  30  and lastly sews or adds the upholstery  34  to make a completed product. In combination, the pocketed spring assembly  32  and border  30  provide a cushioning layer which gives the foundation a softer feel than known foundations. The combination may form what is known in the industry as a topper. 
       FIG. 3A  illustrates an alternative embodiment of the present invention comprising a bedding foundation  10   a  having a covering  34   a . The bedding foundation  10   a  is just like the adjustable bed  10  shown in the other drawings and described herein. However, the bedding foundation  10   a  has a pocketed spring assembly  32   a  having transversely extending strings of springs  80   a  instead of longitudinally extending strings of springs like those shown in the other drawings. In accordance with the present invention, any bedding foundation contemplated by the present invention may have a pocketed spring assembly with transversely, rather than longitudinally extending strings of springs. The pocketed spring assembly  32   a  is located inside border  30   a  as described above. 
     One of ordinary skill in the art will readily recognize that the alternative embodiments of the foundation  10  shown and/or described herein are exemplary only of a wide variety of alternative configurations that are readily possible within the scope of this invention. 
     From the above disclosure of the general principles of the present invention and the preceding detailed description of at least one preferred embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Therefore, we desire to be limited only by the scope of the following claims and equivalents thereof.