VARIABLE COIL DENSITY ANISOTROPIC INNERSPRINGS
Variable coil density anisotropic innersprings in which the placement and density of the coils or spring units varies between one or more regions or areas of the innerspring to provide innersprings with different average spring rates in different zones or regions of the innerspring. Various anisotropic arrangements of coils in innersprings are disclosed.
There are no pending applications related to this application.
FIELD OF THE INVENTIONThe present invention is in the general field of support structures and systems and, more particularly, flexible support structures which include springs.
BACKGROUND OF THE INVENTIONSpring systems for mattress and other reflexive support structures as used in furniture and seating typically have an array of interconnected springs or other recoil devices which support a reflexive support surface. Internal springs in mattresses (“innersprings”) commonly have a plurality of interconnected individual spring units in a matrix with parallel rows and columns. In one of the most common types of mattress innersprings, which can be made by an automated wire-forming process, rows of helical wire springs or “coils” are produced and lined up for insertion into an innerspring assembler which connects adjacent rows of coils by a lacing wire which runs between the rows transverse to a length of the innerspring. The spacing between the coils in each row is uniform, and can be set by adjustment of the innerspring assembler and held in position by the lacing wire. Innersprings of different sizes are made by changing the number of coils in each row and the total number of rows. The coil density and resultant spring rate, support characteristics and feel, such as stiffness and extent of recoil, however is uniform throughout the innerspring where the coils are evenly distributed. Some innersprings also have a larger diameter border wire which is connected to the tops of the coils about a perimeter of the innerspring.
Sleeping mattresses are constructed with a wide variety of materials over and about the innerspring. Some of the materials are provided for enhancing the structural and reflexive properties of the innerspring, including support characteristics at the edges of the innerspring and mattress. For example, U.S. Pat. No. 5,787,532 discloses foam wall structures which fit with the perimeter coils of a mattress innerspring to stiffen the edges of the mattress. Regardless of the amount or different types of materials positioned about the innerspring or even connected to the innerspring, the homogeneous isotropic spring properties and support characteristics of the innerspring as a result of the even spacing and placement of the coils or spring units is not altered.
SUMMARY OF THE INVENTIONThe present disclosure is of anisotropic innersprings in which the placement and density of the coils or spring units varies between one or more regions or areas of the innerspring. As used herein, the terms “anisotropic” and “anisotropy” are used with reference to innersprings in the physical meaning, i.e., having unequal physical properties in different areas or zones or regions or in different dimensions. In the context of innersprings, the anisotropy refers to the density of springs or coils and the consequent average spring rate and/or firmness of different regions of the innerspring resulting from the density and arrangement of coils in one or more regions of the innerspring, which differs from the density and arrangement of coils and average spring rate in other regions of the same innerspring. A region of an anisotropic innerspring of the disclosure is defined by groups of a plurality of coils which are positioned relatively at a common spacing or density. The spacing of the coils within the regions is different from region to region, so that the coil density is different from region to region. The padding and upholstery materials which are combined with the innerspring to form a mattress may be selected and arranged according to the density of coils of the region of the innerspring over which the materials are positioned.
Another aspect of the disclosure and invention is an anisotropic innerspring with different numbers of coils in different regions of the innerspring, the innerspring having a plurality of interconnected coils arranged with axes of the coils parallel and ends of the coils located in common respective planes, the innerspring having multiple regions defined by groups of coils with axes of the coils spaced apart at a common distance, including a first region with coil axes spaced at a first distance and a second region with coil axes spaced at a second distance which is greater than the first distance; the coils of the multiple regions of the innerspring being interconnected by lacing wires which extend between the coils and from one region of the innerspring to another region of the innerspring.
And a further general concept of the disclosure and invention is an innerspring of the type which can be used in a mattress or other flexible support system which has a plurality of interconnected coils arranged with axes of the coils parallel and respective ends of the coils in common planes which define opposed support planes of the innerspring; a first group of coils arranged with axes of the coils of the first group spaced apart at a common first distance, the first group of coils defining a first region of the innerspring; a second group of coils arranged with axes of the coils of the second group spaced apart at a common second distance which is greater than the second fixed distance, the second group of coils defining a second region of the innerspring, whereby a density of coils in the first region is greater than a density of coils in the second region, and a coil density of the first region is greater than a coil density of the second region.
These and other concepts and aspects of the disclosure and the inventions hereof are described in further detail in the following Detailed Description made with reference to the accompanying Drawings.
As shown in the Figures, a variable coil density anisotropic innerspring, indicated in its entirety at 10, is assembled with a plurality of springs or coils 20, shown as generally helical form coils with first and second (or upper and lower) ends 21, 22 and a coil body 23, which as illustrated is in the form of a helix which extends between the coil ends. Other types and shapes of springs or coils may be used in accordance with the principles of the disclosure, which is primarily concerned with the placement and relative placement of springs or coils within an innerspring, and is therefore not limited to any particular type or shape of spring or coil. As used herein, the term “coil” means and includes all forms of springs and coils which can be used in an innerspring constructed according to the principles of the disclosure.
As shown in
In conventional innersprings, the relative lateral spacing between helical form coils in each row of coils, i.e., the lateral distance between the axes of two adjacent coils or between the outermost radii of two adjacent coils, is commonly measured and set with reference to the coil pitch, which is the linear distance from one convolution of the coil to an adjacent convolution, measured at the outer radius of the coil convolutions and parallel to the longitudinal axis of the coil. A typical uniform coil spacing in an innerspring may be, for example, two pitches, meaning that each coil is laterally spaced from adjacent coils in a row at a distance of one to two times the coil pitch. The coil spacing thus set determines the coil density and overall spring rate of the innerspring. The coil spacing between adjacent rows of coils is generally very close, even to the point of being tangent or with some overlap, as is necessary for the small diameter helical lacing wire to wrap around the adjacent convolutions at the ends of the coils. Thus the lateral spacing of the coils in each row can be adjusted and varied in accordance with the present disclosure, as for example by setting the innerspring assembler spacing. One representative example of lateral spacing of coils in the rows, as shown in
Other non-limiting examples and embodiments include closer coil spacing on one side or end of an innerspring; spacing which gradually or abruptly increases or decreases in the width or length directions of the innerspring or in both the width and length directions; variable spacing which alternates, such as pairs or groups of coils which are closely spaced or tangent with the pairs or groups separated by larger spacings; or different coil spacings from row to row, such as one row wherein the coils are closely spaced or tangent, and another row wherein the coils are at greater spacings. For automated assembly of innersprings of the disclosure, any coil spacing which the innerspring assembler can establish can be used to produce a variable coil density anisotropic innerspring of the disclosure.
The variable coil density anisotropic innersprings of the disclosure can be manufactured with the same total number of coils as in conventional isotropic innersprings of the same overall size, e.g. twin, queen, king, because the conservation of coil spaces in the more dense regions is used in the less dense regions.
Another aspect of the innerspring designs of the disclosure, wherein there are regions of the innerspring with differing coil density as a result of variable lateral spacing in the coil rows R, is that each region by itself may be isotropic so that it provides uniform spring effect and support. The boundary of one region of lesser coil density by a region of greater coil density contributes to torsional rigidity of the innerspring as a whole, laterally or longitudinally. For example, the greater coil density of the regions defined by columns C11-C31 and C1r-C3r provided mechanical resistance to any tendency of the remaining central region to deflect or compress laterally from lateral or torsional forces on the coils of the central region.
Another aspect of the disclosure, and in particular an aspect of the anisotropic nature of the innersprings of the disclosure, is the gauge of wire which is used to form the coils. The wire gauge may be varied according to the location and density (i.e., spacing) of the coils. For example, coils which are located in areas or regions of greater density, such as the coils in columns C11-C31 and C1r-C3r, may be made of wire of a different size gauge (smaller or larger) than the wire of the coils in the remaining areas where the coil density is less. For example, the coils of columns C11-C31 and C1r-C3r if made of heavier gauge wire will produce an innerspring with even greater stiffness in the perimeter regions than if all of the coils of the innerspring are made of the same gauge wire. Related to this design variable is the size and configuration of the coils. For example, the coils located in regions of greater coil density may have a different (greater or smaller) diameter to the coil ends and/or the helical coil body than that of the coils in the regions of lesser coil density. By varying these parameters, the overall spring rates of the various regions of an innerspring can be formed to close specifications. Another non-limiting design example of this aspect of the disclosure is to form the coils located at the perimeter of the innerspring from relatively heavier gauge wire to further contribute to edge support and anti-roll-off characteristics.
The foregoing descriptions are of representative embodiments of the principles and concepts of the disclosure which encompass and include other types of anisotropic innersprings with variable coil densities.
Claims
1. An anisotropic variable coil density innerspring comprising a plurality of coils interconnected in an anisotropic array wherein relative spacing between axes of the coils arranged in rows and columns in the array is not constant throughout the innerspring, and lacing wires which extend between the coils to interconnect the coils in the anisotropic array and maintain the relative spacing between the axes of the coils.
2. The innerspring of claim 1 wherein the coils in at least two columns of coils of the array located at longitudinal perimeters of the innerspring are more closely spaced than other coils in the array.
3. The innerspring of claim 1 wherein the spacing of coils in each row of the coils of the innerspring is not constant and the spacing of coils in each column of coils of the innerspring is constant.
4. The innerspring of claim 1 wherein a density of coils in the longitudinal perimeter regions of the innerspring is greater than a density of coils in other regions of the innerspring.
5. The innerspring of claim 1 wherein an average spring rate of the longitudinal perimeter regions is greater than an average spring rate of other regions of the innerspring.
6. An innerspring comprising:
- an anisotropic array of interconnected coils arranged in columns in rows with a common number of coils in each column and row;
- at least two columns of coils spaced apart at a first distance, and at least two other column of coils spaced at a second distance which is greater than the first distance;
- the coils being interconnected by lacing wires located between each row of coils and oriented transverse to the columns of coils.
7. The innerspring of claim 6 wherein perimeter longitudinal regions of the innerspring each comprise at least two columns of coils spaced apart at the first distance.
8. The innerspring of claim 6 wherein a central longitudinal region is comprised of at least two columns of coils spaced at the first distance, and columns of coils lateral to the central longitudinal region are spaced from the central longitudinal region at the second distance.
9. The innerspring of claim 6 wherein the lacing wires extend between columns of coils spaced at the first distance and columns of coils spaced at the second distance.
10. An anisotropic innerspring with different numbers of coils in different regions of the innerspring, the innerspring comprising;
- a plurality of interconnected coils arranged with axes of the coils parallel and ends of the coils located in common respective planes, the innerspring having multiple regions defined by groups of coils with axes of the coils spaced apart at a common distance, including a first region with coil axes spaced at a first distance and a second region with coil axes spaced at a second distance which is greater than the first distance;
- the coils of the multiple regions of the innerspring being interconnected by lacing wires which extend between the coils and from one region of the innerspring to another region of the innerspring.
11. The anisotropic innerspring of claim 10 wherein the plurality of interconnected coils are arranged in columns and rows.
12. The anisotropic innerspring of claim 11 wherein the first region includes at least a portion of a perimeter of the innerspring.
13. The anisotropic innerspring of claim 10 wherein the first region includes at least two adjacent rows or columns of coils.
14. The anisotropic innerspring of claim 10 wherein the second region includes at least two adjacent rows or columns of coils.
15. The anisotropic innerspring of claim 10 wherein the first region extends along a length of the innerspring.
16. The anisotropic innerspring of claim 10 wherein rows of coils of the innerspring are spaced apart at a constant distance in all regions of the innerspring.
17. The anisotropic innerspring of claim 10 wherein the lacing wires extend transversely between columns of coils and from one region of the innerspring to another region of the innerspring.
18. The anisotopic innerspring of claim 10 wherein columns of coils of the innerspring are spaced apart at a constant distance in all regions of the innerspring.
19. The anisotropic innerspring of claim 10 wherein a coil density in one region of the innerspring is at least 25% greater than a coil density in another region of the innerspring.
20. The anisotropic innerspring of claim 10 wherein a region of the innerspring with a relatively greater density of coils than another region includes at least a portion of a perimeter of the innerspring.
21. The anisotropic innerspring of claim 10 wherein a region of the innerspring with a relatively greater density of coils than another region is at least partially located in a central region of the innerspring.
22. An innerspring comprising:
- a plurality of interconnected coils arranged with axes of the coils parallel and respective ends of the coils in common planes which define opposed support planes of the innerspring;
- a first group of coils arranged with axes of the coils of the first group spaced apart at a common first distance, the first group of coils defining a first region of the innerspring;
- a second group of coils arranged with axes of the coils of the second group spaced apart at a common second distance which is greater than the common first distance, the second group of coils defining a second region of the innerspring,
- whereby a density of coils in the first region is greater than a density of coils in the second region, and a coil density of the first region is greater than a coil density of the second region.
23. The innerspring of claim 22 wherein the first region of the innerspring has a higher spring rate than the second region of the innerspring.
24. The innerspring of claim 22 wherein all of the coils of the innerspring are located in parallel rows which extend through the first region and through the second region.
25. The innerspring of claim 22 wherein all of the coils of the innerspring are located in parallel columns which extend through the first region and through the second region.
26. The innerspring of claim 22 wherein the coils are arranged in columns and rows and wherein the coils are spaced at a common distance in each row of coils of the innerspring.
27. The innerspring of claim 22 wherein the coils are arranged in columns and rows and wherein the coils are spaced at a common distance in each column of coils of the innerspring.
28. The innerspring of claim 22 wherein the coils are interconnected by lacing wires which extend between each row of coils and which extend from the first region to the second region of the innerspring.
29. The innerspring of claim 22 further comprising a third group of coils defining a third region of the innerspring wherein axes of the coils in the third group are spaced at a common third distance which is different from the spacing of coils in the first region and different from the spacing of coils in the second region.
30. The innerspring of claim 22 in a one-sided mattress.
Type: Application
Filed: Feb 5, 2008
Publication Date: Aug 6, 2009
Inventors: Larry K. DeMoss (Greensboro, NC), James A. Beamon (Jamestown, NC), Brian M. Manuszak (Thomasville, NC), Wayne Rumbaugh (High Point, NC)
Application Number: 12/025,888
International Classification: A47C 23/04 (20060101);