Multilayered pocketed bedding or seating product

Information

  • Patent Grant
  • 6256820
  • Patent Number
    6,256,820
  • Date Filed
    Wednesday, February 9, 2000
    25 years ago
  • Date Issued
    Tuesday, July 10, 2001
    23 years ago
Abstract
A bedding or seating product comprising a spring core made up of a plurality of parallel strings of springs joined to each other. Each of the strings of springs comprises a row of interconnected pocketed coil springs. The pocket of fabric surrounding each of these coil springs is divided into at least two subpockets by at least one line of attachment of opposite sides of the fabric to each other. Each of these subpockets contains one portion of the coil spring, thus resulting in a multilayered product.
Description




FIELD OF THE INVENTION




This invention relates to spring assemblies for mattresses, cushions and other bedding or seating products.




BACKGROUND OF THE INVENTION




Strings of individually pocketed springs are known. Multiple such strings of springs have been combined in a parallel fashion to create a spring assembly. Each of the coil springs of the string is contained within an individual pocket of fabric which extends from the top to the bottom of the spring. Typically, each of the springs within the string has identical features or characteristics. Consequently, bedding or seating products made from identical strings of pocketed springs have uniform characteristics throughout the bedding or seating product.




Published PCT patent application No. WO 99/35081 discloses a mattress having two layers of pocketed springs. Each of the springs in each layer is individually pocketed, and the springs of the upper layer are directly above the corresponding springs of the lower layer. A pair of such corresponding springs, one above the other, are enclosed in an external cover and separated from one another by a generally horizontal partition wall of fabric. The springs of the upper layer are “softer” than the springs of the lower layer. Thus, this mattress is able to provide a soft upper layer and a harder lower supporting layer. By using springs having different characteristics in the different layers of the mattress, differing degrees of firmness may be imparted to the mattress.




In order to make such a mattress, a large number of coil springs must be used. For every lower spring, there must be a corresponding upper spring directly above it. Additionally, each of these springs must be individually pocketed. This large number of coil springs and the effort required to individually pocket each spring increases the cost of manufacturing the mattress, and also the time required to manufacture it. Additionally, the upper spring may move sideways relative to the lower spring, causing the springs to move out of alignment with one another and create a bump, indentation or uneven spot in the mattress. Another possibility with such a mattress is that the spring of the upper layer may rotate relative to the spring of the lower layer, reducing the ability of the mattress to function as desired.




Therefore, it has been one objective of the present invention to provide a multilayered bedding or seating product made of individually pocketed springs without using different springs for the upper and lower layers.




Another objective of the present invention has been to provide a pocketed bedding or seating product made of a plurality of similarly constructed strings of pocketed springs joined together.




Still another objective of the present invention has been to provide a pocketed bedding or seating product which may be custom manufactured for a particular application.




SUMMARY OF THE INVENTION




The invention of this application which accomplishes these objectives comprises a bedding or seating product. The bedding or seating product comprises a spring core and an upholstered covering surrounding the spring core. The spring core comprises a plurality of parallel strings of springs joined together. Each of the strings of springs comprises a row of interconnected pocketed coil springs. Each of the pocketed coil springs comprises a coil spring surrounded with a pocket of fabric, as is conventional.




However, the coil springs of the string of springs may not be conventional; i.e., they may not have uniform characteristics from top to bottom as do conventional coil springs. However, it is envisioned that coil springs utilized in the practice of this invention may in at least one embodiment be conventional coil springs having the same physical properties or characteristics, i.e. pitch, coil diameter, wire thickness (guage), heat treatment, etc., from top to bottom. In several preferred embodiments of this invention though, the coil springs have at least two distinctly different portions, each portion of which has at least one different physical characteristic than at least one other portion of the spring.




For example, in one embodiment of the present invention, each of the springs has two portions, an upper portion and a lower portion. At least one characteristic of the upper portion is different than the corresponding characteristic of the lower portion, i.e., the upper portion being a different gauge wire or a different pitch than the lower portion of the spring. Each of the springs has the same set of characteristics and is similarly oriented, resulting in a bedding or seating product with a uniform hardness or “feel” on one surface. However, when the bedding or seating product is flipped over, the bedding or seating product will have a different firmness or “feel” due to the different characteristics of the springs.




In another embodiment of the present invention, each of the springs has three portions: a pair of end portions and a middle portion therebetween. The characteristics of the ends portions are identical but yet different from the characteristics of the middle portion of the spring. A bedding or seating product made from such strings of springs has the same firmness or “feel” no matter which side of the mattress is facing up.




The concept of the present invention may also be used to posturize a bedding or seating product, i.e., make certain regions or portions firmer than other areas or portions of the bedding or seating product. This is accomplished by grouping together multiple strings of springs having identical characteristics in one region of a bedding or seating product. The strings of springs of the other regions have different characteristics so as to impart different firmnesses to the different regions.




Within a string of springs, each pocket of fabric is divided into at least two subpockets by at least one line of attachment. Each line of attachment preferably comprises at least one weld joining opposite sides or plies of the fabric to each other. The line of attachment may be a continuous or broken line. The plies may be welded, sewn or otherwise secured together. The line(s) of attachment is/are located so that each of the subpockets contains one of the portions of the coil spring. Thus the bedding or seating product is multilayered, each layer comprising a plurality of subpockets, each of the subpockets containing a portion of a coil spring.




The bedding or seating product typically has a longitudinal dimension and a transverse dimension, the longitudinal dimension being greater than the transverse dimension. However, the longitudinal dimension and transverse dimension may be identical in a square bedding or seating product. In the invention of the present application, the strings of springs may extend longitudinally or transversely, depending upon the desired effect.




Adjacent strings of springs of the bedding or seating product are preferably glued together but may be otherwise secured to each other. At least one border wire may extend around the perimeter of the bedding or seating product and is secured to select outermost pocketed coil springs. A first or lower border may be secured to the lower end turns of the coil springs of the outermost strings. A second or upper border wire may be secured to the upper end turns of the coil springs of the outermost strings or, alternatively, secured to intermediate convolutions of the coil springs of the outermost strings of springs. When secured to intermediate convolutions of the outermost coil springs, the upper border wire is spaced downwardly below the upper end turns of the springs. In either case the upper border wire is generally horizontally oriented and defines a generally horizontal plane. In the event the upper border wire is spaced below the upper surface of the strings of springs, one of the subpockets of each of the pocketed springs is located above the generally horizontal plane defined by the upper border wire. If the upper border wire is placed in such a location, the upper portions of springs located above the generally horizontal plane may be made softer or less resilient than the lower portions of the springs below the generally horizontal plane, thus providing the bedding or seating product with a cushioning, soft upper layer above the main body of the bedding or seating product. These and other objects and advantages of the present invention will be more readily apparent from the following drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

is a perspective view of a bedding product made in accordance with the invention of this application comprising a plurality of transversely extending strings of springs surrounded by a generally rectangular border wire;





FIG. 1B

is a perspective view of a bedding product made in accordance with the present invention, the strings of springs extending longitudinally and being surrounded by a generally rectangular border wire;





FIG. 2A

is a side elevational view, partially broken away, of a string of springs made in accordance with one embodiment of the present invention;





FIG. 2B

is a side elevational view, partially broken away, of a string of springs made in accordance with a second embodiment of the present invention;





FIG. 3A

is a side elevational view, partially cut away, of a portion of the string of springs of

FIG. 2A

;





FIG. 3B

is a side elevational view, partially cut away, of a portion of the string of springs of

FIG. 2B

;





FIG. 4

is a perspective view of a string of springs being joined to a portion of a spring core;





FIG. 5A

is a perspective view of a method of manufacturing a spring core made of a plurality of strings of springs joined together at least in part by upper and lower scrim sheets;





FIG. 5B

is a perspective view of an alternative method of manufacturing a spring core made up of strings of springs held together at least in part by upper and lower scrim sheets;





FIG. 6A

illustrates a method of manufacturing a spring core made up of a plurality of strings of springs held together with supplemental fabric strips, the supplemental fabric strips being perpendicular to the longitudinal dimension of the strings of springs;





FIG. 6B

illustrates an alternative method of manufacturing a spring core made up of a plurality of strings of springs held together with supplemental fabric strips, the supplemental fabric strips being perpendicular to the longitudinal dimension of the strings of springs;





FIG. 7A

illustrates a method of manufacturing a spring core made up of a plurality of strings of springs held together with supplemental fabric strips, the supplemental fabric strips being parallel the longitudinal dimension of the strings of springs;





FIG. 7B

illustrates an alternative method of manufacturing a spring core made up of a plurality of strings of springs held together with supplemental fabric strips, the supplemental fabric strips being parallel the longitudinal dimension of the strings of springs.











DETAILED DESCRIPTION OF THE DRAWINGS




Referring to the drawings, and particularly to

FIG. 1A

, there is illustrated a bedding or seating product


10


comprising a spring core


12


and an upholstered covering


14


surrounding the spring core


12


. The spring core


12


comprises a plurality of parallel strings of springs


16


.




One embodiment of the present invention is illustrated in

FIGS. 2A and 3A

. In this embodiment the spring core


12


comprises a plurality of strings of springs


16




a


, one of which is illustrated in FIG.


2


A. As illustrated in

FIG. 2A

, the string of springs


16




a


has a longitudinal dimension or length


18


and a height


20


. The string of springs


16




a


comprises a row of interconnected fabric pockets


22


, each containing a coil spring


24


. The combination of the coil spring


24


and the fabric pocket


22


is considered a pocketed coil spring


26


. One such pocketed coil spring


26


is illustrated in FIG.


3


A. As is known in the art, each string of springs


16




a


comprises a piece of fabric folded over on itself encapsulating a plurality of parallel springs


24


. Opposite sides or plies of the fabric are sewn, welded or otherwise secured together in order to create a pair of outmost seams


28


, a top seam


30


and a plurality of interior seams


32


which separate adjacent coil springs


24


from one another. Although the seams


28


,


30


and


32


are each illustrated as being a plurality of spaced, linear segments, they may comprise continuous lines or a series of dots as well without departing from the spirit of this application.




Referring to

FIG. 3A

, each of the pocketed coil springs


26


of the present invention comprises a coil spring


24


enclosed in a fabric pocket


22


. The coil spring


24


has an upper end turn


33


, a lower end turn


34


and a plurality of central convolutions


36


therebetween. In one embodiment, each of the coil springs


24


has uniform physical properties throughout. In another embodiment of the present invention, each of the coil springs


24


has a first portion


38


and a second portion


40


, each of the portions having different physical characteristics such as different thicknesses, coil pitches, coil diameters, heat treatments, etc. In the coil spring


24


illustrated in

FIG. 3A

, the first portion


38


of the coil spring


24


is located above the second portion


40


of the coil spring


24


and has a greater helical pitch than the second portion


40


. Additionally, the first portion


38


is made of a thinner gauge wire than the second portion


40


of the coil spring


24


. At location


41


the coil spring


24


changes characteristics.




As illustrated in

FIGS. 2A and 3A

, the individual fabric pocket


22


in which is located the coil spring


24


is divided into at least two subpockets


42


and


44


by a line of attachment


46


of opposed plies of the fabric pocket together. A first or upper subpocket


42


contains the first portion


38


of the coil spring. A second or lower subpocket


44


contains the second portion


40


of the coil spring. Thus, the generally horizontally oriented line of attachment


46


divides the pocketed coil spring


26


into two layers, an upper layer


48


and a lower layer


50


. In at least one embodiment of the present invention, the upper layer


48


has different characteristics than the lower layer


50


due to the nature of the spring portions


38


,


40


inside the subpockets


42


,


44


. In the product illustrated in

FIGS. 2A and 3A

, the upper layer


48


has a soft feel, whereas the lower layer


50


has a more firm, stronger feel due to the characteristics of the portions


38


,


40


of coil springs


24


located in the respective subpockets


42


,


44


.





FIGS. 2B and 3B

illustrate an alternative embodiment of the present invention. In this embodiment, each coil spring


51


within a string


16




b


of coil springs is divided into three portions: a pair of end portions


52


and a middle portion


54


therebetween. As illustrated in

FIG. 3B

, each of the end portions


52


has identical characteristics different from the characteristics of the middle portion


54


. The entire coil spring


51


is encapsulated in a fabric pocket


56


. The fabric pocket


56


is divided into three subpockets


58


,


59


and


60


by a pair of lines of attachment


62


and


64


. Line of attachment


62


separates subpockets


58


and


59


and line of attachment


64


separates subpockets


59


and


60


. End portion


52


of the coil spring


51


is located in subpocket


58


, middle portion


54


inside subpocket


59


and end portion


52


inside subpocket


60


.




A spring core made of a plurality of strings of springs


16




b


(seen in

FIG. 2B

) has the same firmness on the top and bottom surfaces of the spring core. Thus, a bedding or seating product made of a plurality of strings of springs


16




b


joined together has the same feel no matter which side of the mattress is upwardly directed or exposed.




One method of manufacturing the spring core


12


of the bedding or seating product


10


is illustrated in FIG.


4


. This method comprises joining a plurality of parallel string of springs


16


to each other.




Referring to

FIG. 4

, a string of springs


16




c


is moved in the direction of arrows


72


until it abuts an outermost string of springs


16




d


which is part of a subassembly


74


made of a plurality of strings of springs (two being shown). A sinuous-shaped glue line


76


is placed on the outer surface of the fabric of the string of springs


16




d


. When string of springs


16




c


abuts against the string of springs


16




d


, pressure is applied and the glue is allowed to dry, thus securing the string of springs


16




c


to the string of springs


16




d


. Although a sinuous-shaped line of glue is illustrated and described, the glue may assume other shapes and configurations such as individual dots or a plurality of linear segments, for example. Other attachment methods such as hog rings, welds or any other type of fastener may be used to secure adjacent strings of springs to each other.




Referring to

FIG. 1A

, the bedding or seating product


10


has a longitudinal dimension L and a transverse dimension W, the longitudinal dimension L being greater than the transverse dimension W. As illustrated in

FIG. 1A

, the strings of springs


16


may extend transversely (parallel the transverse dimension W). Alternatively, as illustrated in

FIG. 1B

, the strings of springs


16


may extend longitudinally (parallel the longitudinal dimension L).




As illustrated in

FIGS. 1A and 1B

, a least one border wire may extend around the perimeter of the spring core


12


.

FIG. 1A

illustrates a lower border wire


80


secured to the lower end turns


34


of the outermost coil springs


24


of the spring core


12


.

FIG. 1A

also illustrates an upper border wire


82


surrounding the spring core


12


. The upper border wire


82


is secured to intermediate convolutions


36


of the coil springs


24


and is spaced a distance below the upper end turns


33


of the coil springs


24


. The border wire


82


is generally horizontally oriented, defining a horizontal plane P. The upper border wire


82


is preferably at the location


41


(see

FIG. 3A

) at which the characteristics of the coil springs


24


change so that the upper or first portion


38


of coil spring


24


above the border wire having one set of characteristics is located above the upper border wire


82


, and the lower or second portion


40


of coil spring


24


having a different set of characteristics is located below the border wire


82


. The upper subpockets


42


are located above the plane P, and the lower subpockets


44


of the strings of springs are located below the border wire


82


and horizontal plane P, thus dividing the spring core


12


into upper and lower layers.





FIG. 1B

illustrates a plurality of strings of springs


16


longitudinally oriented, a lower border wire


84


and an upper border wire


86


.




The lower border wire


84


is secured to the lower end turns


34


of the outermost coil springs of the spring core, and the upper border wire


86


is secured to the upper end turns


33


of the outermost coil springs of the spring core, as is conventional. Depending on the desired effect, the upper border wire


86


may be secured to the upper end turns or the intermediate convolutions of the outermost springs regardless of which direction the strings of springs are oriented.





FIGS. 5A and 5B

illustrate alternative methods of combining multiple strings of springs of the present invention into a spring core. Referring to

FIG. 5A

, a plurality strings of springs


16




e


, each having an upper surface


88


and a lower surface


90


, are aligned. An upper scrim sheet


92


is glued or otherwise secured to the upper surfaces


88


of each of the strings of springs


16


and, similarly, a lower scrim sheet


94


is glued or otherwise secured to the lower surfaces


90


of the strings of springs


16


.




An alternative method of joining multiple strings of springs using scrim sheets is illustrated in FIG.


5


B. Using this method, one string of springs


16




f


is moved in the direction of arrows


96


until it abuts the outermost string of springs


16




g


of a partial spring core


98


. Once in such a location, the upper and lower scrim sheets


100


,


102


may be secured to the upper and lower surfaces


104


,


106


, respectively, of the string of springs


16




f


. One at a time an additional string of springs is secured to the scrim sheets


100


and


102


until the appropriate length and width of spring core is obtained. Additionally, if desired, string of springs


16




f


may be secured to the outermost string of springs


16




g


of partial spring core


98


with glue (see FIG.


4


).





FIGS. 6A

,


6


B,


7


A and


7


B illustrate alternative methods of joining together multiple strings of springs to create a spring core.

FIG. 6A

illustrates a plurality of transversely extending strings of springs


16




h


, each string of springs


16




h


having an upper surface


108


and a lower surface


110


.




A plurality of spaced parallel supplemental fabric strips


112


are secured to the upper surfaces


108


of the strings of springs


16




h


, and a plurality of parallel spaced supplemental fabric strips


114


are secured to the lower surfaces


110


of the parallel strings of springs


16




h


. In the method illustrated in

FIG. 6A

, all the strings of springs


16




h


are aligned before the supplemental fabric strips


112


,


114


are attached to the upper and lower surfaces


108


,


110


of the strings of springs


16




h.







FIG. 6B

illustrates an alternative method of creating a spring core. Using this method one transversely extending string of springs


16




i


is moved in the direction of arrows


117


until it abuts an outermost string of springs


16




j


of a partial spring core


118


. Each of the strings of springs


16




i


has an upper surface


115


and a lower surface


116


. Upper supplemental fabric strips


120


are then lowered downwardly in the direction of arrow


122


and secured to the upper surface


115


of the outermost string of springs


16




i


. Likewise, lower supplemental fabric strips


124


are raised in the direction of arrow


126


and glued or otherwise secured to the lower surface


116


of the outermost string of springs


16




i


. Utilizing this method, strings of springs are secured one at a time to the partial spring core until the desired size of spring core is created.





FIG. 7A

illustrates a spring core


128


made up of a plurality of parallel strings of springs


16




k


which are extending longitudinally. A plurality of parallel upper supplemental fabric strips


130


are secured to the upper surfaces


132


of the strings of springs


16




k


, each supplemental fabric strip


130


being joined to two adjacent strings of springs. Similarly, lower supplemental fabric strips


134


are moved in the direction of arrow


136


and secured to the lower surfaces


138


of the strings of springs


16




k.






Referring to

FIG. 7B

, a partial spring core


140


having a plurality of upper supplemental fabric strips


142


and lower supplemental fabric strips


144


securing a plurality of strings of springs


16




l


together may be increased in size by adding an additional string of springs


16




m


in the direction of arrows


146


. An additional upper supplemental fabric strip


148


is moved downwardly in the direction of arrow


150


and secured to the upper surfaces of adjacent strings of springs


16




l


and


16




m


. Similarly, lower supplemental fabric strip


152


is moved upwardly in the direction of arrow


154


and joined to the lower surfaces of strings of springs


16




l


and


16




m.






Although we have described several preferred embodiments of our invention, we do not intend to be limited except by the scope of the following claims.



Claims
  • 1. A bedding or seating product comprising:a spring core comprising a plurality of parallel strings of springs, each of said strings of springs comprising a row of interconnected pocketed coil springs, each of said pocketed coil springs comprising a coil spring surrounded by a pocket of fabric, at least selected ones of said pockets of fabric being divided into at least two subpockets by at least one line of attachment, each of said subpockets containing one portion of one of said coil springs; and an upholstered covering surrounding said spring core.
  • 2. A bedding or seating product comprising:a spring core comprising a plurality of parallel strings of springs, each of said strings of springs comprising a row of interconnected pocketed coil springs, each of said pocketed coil springs comprising a coil spring surrounded by a pocket of fabric, at least selected ones of said pockets of fabric being divided into at least two subpockets by at least one line of attachment, each of said subpockets containing one portion of one of said coil springs.
  • 3. The bedding or seating product of claim 2 wherein at least selected ones of said coil springs have at least two portions of different characteristics.
  • 4. The bedding or seating product of claim 2 wherein said product has a longitudinal dimension and a transverse dimension, said longitudinal dimension being greater than said transverse dimension, said strings of springs extending longitudinally.
  • 5. The bedding or seating product of claim 2 wherein said product has a longitudinal dimension and a transverse dimension, said longitudinal dimension being greater than said transverse dimension, said strings of springs extending transversely.
  • 6. The bedding or seating product of claim 2 further comprising at least one border wire extending around strings of coil springs, said at least one border wire being secured to select outermost pocketed coil springs.
  • 7. The bedding or seating product of claim 2 wherein a border wire is secured to said spring core and defines a generally horizontal plane, one of said subpockets of each of said pocketed coil springs being above said generally horizontal plane.
  • 8. The bedding or seating product of claim 2 wherein adjacent strings of springs are glued together.
  • 9. The bedding or seating product of claim 2 wherein each of said strings of springs is secured to at least one scrim sheet.
  • 10. The bedding or seating product of claim 2 wherein said strings of springs are held together with supplemental fabric strips.
  • 11. The bedding or seating product of claim 10 wherein said supplemental fabric strips are transversely extending.
  • 12. The bedding or seating product of claim 10 wherein said supplemental fabric strips are longitudinally extending.
  • 13. A string of springs for inclusion in a bedding or seating product, said string of springs comprising a row of interconnected pocketed coil springs, each of said pocketed coil springs comprising a coil spring surrounded with a pocket of fabric, said pocket of fabric being divided into at least two subpockets by at least one line of attachment, each of said subpockets containing one portion of said coil spring.
  • 14. The string of springs of claim 13 wherein each of said coil springs has at least two portions of different characteristics.
  • 15. The string of springs of claim 13 wherein each of said coil springs has two different portions, each of said portions being within one of said subpockets.
  • 16. The string of springs of claim 14 wherein said portions of said coil spring are of different thicknesses.
  • 17. The string of springs of claim 14 wherein said portions of said coil spring are of different pitches.
  • 18. The string of springs of claim 13 wherein said string of springs is joined to other similar strings of springs by gluing strings of springs together to create a spring core.
  • 19. The string of springs of claim 13 wherein each of said coil springs has three portions, a pair of end portions and a middle portion, each of said end portions having identical characteristics.
  • 20. The string of springs of claim 19 wherein said middle portion of said coil spring has different characteristics than the characteristics of said end portions.
  • 21. A pocketed coil spring for use in a bedding or seating product, said pocketed coil spring comprising a coil spring surrounded with a pocket of fabric, said pocket of fabric being divided into at least two subpockets by at least one line of attachment, wherein each of said subpockets contains one portion of said coil spring.
  • 22. The pocketed coil spring of claim 21 wherein said coil spring has two different portions, each of said portions being within one of said subpockets.
  • 23. The pocketed coil spring of claim 21 wherein said coil spring has at least two portions of different characteristics.
  • 24. The pocketed coil spring of claim 23 wherein said portions of said coil spring are of different thicknesses.
  • 25. The pocketed coil spring of claim 23 wherein said portions of said coil spring are of different pitches.
  • 26. The pocketed coil spring of claim 23 wherein said coil spring has three portions, a pair of end portions and a middle portion, each of said end portions having identical characteristics.
  • 27. The pocketed coil spring of claim 26 wherein said middle portion of said coil spring has different characteristics than the characteristics of said end portions.
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