Patent Application
20240349907
The present invention relates to spring cores having an integrated cushioning layer. In particular, the present invention relates to spring cores that include a plurality of coil springs and a cushioning layer that is positioned atop the coil springs and that extends below an upper end convolution of each coil spring.
Spring assemblies that make use of pocket coil springs, which are also known as wrapped coils, encased coils, encased springs, or Marshall coils, are generally recognized as providing a unique feel to a mattress when used as a part of a spring assembly because each discrete coil is capable of moving independently to support the body of a user, or a portion thereof, resting on the mattress. In particular, in spring cores including a plurality of pocket coil spring assemblies, each coil is wrapped in a fabric pocket and moves substantially independently of the other coils in the spring core to thereby provide individualized comfort and contouring to the body of a user. Moreover, as a result of moving substantially independently from one another, the pocket coils also do not directly transfer motion from one pocket coil to another, and, consequently, the movement of one user resting on a mattress assembly using pocket coils will not disturb another user resting on the mattress assembly. In this regard, mattress assemblies constructed with a spring core using pocket coil springs are generally recognized as providing a soft and luxurious feel, and are often more desirable than a traditional inner spring mattress. Accordingly, a spring core that makes use of pocket coil springs and that further improves the unique feel and support provided by traditional pocket coil springs would be both highly desirable and beneficial.
The present invention includes spring cores having an integrated cushioning layer. In
particular, the present invention includes spring cores that are comprised of a plurality of coil springs and a cushioning layer that is positioned atop the coil springs and that extends below an upper end convolution of each coil spring.
In one exemplary embodiment of the present invention, an exemplary spring core is provided as part of a mattress assembly, which further includes an upper body supporting layer, a lower foundation layer, and a side panel extending between the upper body supporting layer and the lower foundation layer and around the entire periphery the spring core. The spring core itself is comprised of a plurality of coil springs with each of the coils having an upper portion and a lower portion that collectively define an interior cavity of the coil spring. Each of the coil springs is encased by a fabric pocket that includes a top area, which covers the upper portion of each coil spring, as well as a bottom area, which covers the lower portion of each coil spring. The spring core further includes a continuous upper fabric layer that covers the upper portion of each coil spring and that defines a recess in the interior cavity of each coil spring, an intermediate recess between each coil spring, or both. Additionally included in the spring core is a cushioning layer that is positioned atop each of the coil springs and that includes a bottom surface extending into each recess defined by the continuous upper fabric layer and a substantially planar top surface. In this regard, the top surface of the cushioning layer thus forms the first support surface of the spring core, while the bottom area of the fabric pockets along with the lower portion of each of the coil springs forms the second support surface of the spring core.
With respect to the fabric pockets, in some embodiments, the top area of each fabric pocket is connected to the bottom area of each fabric pocket within the interior cavity of the coil spring. The top area of the fabric pocket (i.e., the portion of the continuous upper fabric layer which forms the top area of the fabric pocket) can be connected to the bottom area of the fabric pocket by any number of means, including a tuft, a staple, a weld, and the like. By connecting the top area of the fabric pocket to the bottom area of the fabric pocket within the interior cavity of a coil spring, not only is it possible to impart a desired level of pre-compression, stability, and/or stretchability to the coil spring, but the connection of the top area of the fabric pocket to the bottom area of the fabric pocket also creates an additional recess that is defined by the top area of the fabric pocket and that, in certain embodiments, extends into the interior cavity of the coil spring to about half of the total height of the coil spring. In this regard, by joining the top area of a fabric pocket to the bottom area of a fabric pocket, the additional recess provides a suitable area in which the continuous upper fabric layer can extend and thereby defines the recess that is formed by the continuous upper fabric layer and that provides a suitable area onto which a liquid foam precursor can be directly dispensed and allowed to react to form the cushioning layer.
In another exemplary embodiment of the present invention, a spring core is included in an exemplary mattress assembly and comprises a plurality of mini coil springs that are each encased by a fabric pocket. The spring core further comprises a continuous upper fabric layer that extends across an upper portion of each of the plurality of mini coil springs and defines a recess in an interior cavity of each of the coil springs. The spring core then includes a continuous lower fabric layer that extends across the lower portion of each of the plurality of mini coil springs. The continuous lower fabric layer is connected to the continuous upper fabric layer around and between each of the plurality of mini coil springs, such that the continuous upper fabric layer and the continuous lower fabric layer collectively form a plurality of intermediate recesses between each of the mini coil springs. In this regard, when a liquid foam precursor is dispensed onto the continuous upper fabric layer, the resulting bottom surface of the cushioning layer extends into each of the recesses in the interior cavity of each of the mini coil springs and into each of the intermediate recesses between each of the mini coil springs.
As an even further refinement to the spring cores of the present invention that make use of a continuous upper fabric layer and a continuous lower fabric layer, in another embodiment, an exemplary spring core is includes a plurality of mini coil springs similar to the embodiment described above, but which are each not surrounded by a fabric pocket. Instead, in the further spring core, the continuous upper fabric layer and the continuous lower fabric layer are connected to one another between each of the mini coil springs and to one another within the interior cavity of each of the mini coil springs to define both a recess in the interior cavity of each of the mini coil springs and a plurality of intermediate recesses between each of the mini coil springs.
Still further provided are methods for producing a spring core. In one exemplary implementation of a method for producing a spring core, a pocketed coil array is first provided and is covered by a continuous upper fabric layer to define a recess in the interior cavity of each coil spring. A foam precursor is then dispensed onto the continuous upper fabric layer, for example, by moving the pocketed coil array through a flowing vertical curtain of foam precursor, and the top surface of the foam precursor is subsequently smoothed. The pocket coil array with the foam precursor dispensed on the continuous upper fabric layer is then cured, such as by advancing the array through an infrared curing oven or by other means for curing the foam (e.g., humidity, ultraviolet light, etc.) where the time spent in curing the foam is predetermined to adequately cure the foam precursor into the set foam layer. After the foam precursor has reacted for an appropriate amount of time and the foam precursor has set, the edges of the set foam are then trimmed to produce the exemplary spring core of the present invention.
Further features and advantages of the present invention will become evident to those of ordinary skill in the art after a study of the description, figures, and non-limiting examples in this document.
FIG. I is a perspective view of an exemplary mattress assembly made in accordance
with the present invention, with a portion of the mattress assembly removed to show a spring core in the interior of the mattress assembly;
The present invention includes spring cores having an integrated cushioning layer. In particular, the present invention includes spring cores that are comprised of a plurality of coil springs and a cushioning layer that is positioned atop the coil springs and that extends below an upper end convolution of each coil spring.
Referring first to
With respect to each of the coil springs 20, each exemplary coil spring 20 shown in
With respect to the fabric pockets 30, in the exemplary spring core 12 shown in
With further respect to the fabric pocket 30 and referring still to
Referring still to
With respect to hardness, the flexible foam used in the cushioning layer 40 of the spring core 12 can, in some embodiments, have a hardness of at least about 10 N to no greater than about 80 N, as measured by exerting pressure from a plate against a sample of the material to a compression of at least 40% of an original thickness of the material at approximately room temperature (i.e., 21°° C. to 23°° C.), where the 40% compression is held for a set period of time as established by the International Organization of Standardization (ISO) 2439 hardness measuring standard. In some embodiments, the flexible foam used in the cushioning layer 40 included in spring core 12 of the mattress assembly 10 has a hardness of about 10 N, about 20 N, about 30 N, about 40 N, about 50 N, about 60 N, about 70 N, or about 80 N to provide a desired degree of comfort and body-conforming or supporting qualities.
With respect to density, the flexible foam used in the cushioning layer 40 of the spring core 12 can, in some embodiments, also have a density that assists in providing a desired degree of comfort and body-conforming qualities, as well as an increased degree of material durability. In some embodiments, the density of the flexible foam used in the cushioning layer 40 included in the spring core 12 of the mattress assembly 10 has a density of no less than about 30 kg/m3 to no greater than about 150 kg/m3. In some embodiments, the density of the flexible foam used in the cushioning layer 40 of the spring core 12 is about 10 kg/m3, about 20 kg/m3, about 30 kg/m3, about 40 kg/m3, about 50 kg/m3, about 60 kg/m3, about 70 kg/m3, about 80 kg/m3, about 90 kg/m3, about 100 kg/m3, about 110 kg/m3, about 120 kg/m3, about 130 kg/m3, about 140 kg/m3, or about 150 kg/m3. In some embodiments, the density of the flexible foam used in the cushioning layer 40 of the spring core 12 is about 10 kg/m3 to about 80 kg/m3. Of course, the selection of a flexible foam having a particular density will affect other characteristics of the foam, including its hardness, the manner in which the foam responds to pressure, and the overall feel of the foam. In this regard, it is also appreciated that a flexible foam having a desired density and hardness can readily be selected for a particular mattress assembly or application as desired. However, regardless of the particular properties of the cushioning layer 40, a user's body, or portion thereof, resting on the mattress assembly 10 will be supported by both the cushioning layer 40 as well as the coil springs 20, and thus, will provide a user with the contact feel of foam along with the durability and support of a spring.
Furthermore, and as indicated above, the cushioning layer 40 in the exemplary spring core 12 shown in
In other embodiments, the cushioning layer can comprise an elastomeric gelatinous material that is capable of providing a cooling effect by acting as a thermal dump or heat sink into which heat from a user's body, or portion thereof, positioned on the cushioning layer can dissipate. For example, in such embodiments, the cushioning layer can be comprised of a polyurethane-based gel made by combining Hyperlast® LU 1046 Polyol, Hyperlast® LP 5613 isocyanate, and a thermoplastic polyurethane film, which are each manufactured and sold by Dow Chemical Company Corp. (Midland, MI), and which can be combined to produce a gel having a thermal conductivity of 0.1776 W/m*K, a thermal diffusivity of 0.1184 mm2/s, and a volumetric specific heat of 1.503 MJ (/m3K) as established by the International Organization of Standardization (ISO) 22007-2 volumetric specific heat measuring standard.
Furthermore, it is appreciated that the wire gauge, spring constant, pre-compression, and overall geometry of the coil spring used in a particular mattress assembly can also be readily varied and used to impart a particular feel or characteristic in an exemplary mattress assembly without departing from the spirit and scope of the present invention.
Referring still to
In the exemplary embodiment shown in
As a refinement of the spring cores and mattress assemblies of the present invention, rather than making use of a plurality of coil springs encased by fabric pockets and then covered by a continuous upper fabric layer that only connects the upper portions of each coil spring to one another, it is also contemplated that a plurality of coil springs can be covered by both a continuous upper fabric layer and a continuous lower fabric layer that are then connected to each other to provide a more unitary spring core construction. For example, and referring now to
Referring still to
As an even further refinement to the spring cores of the present invention that make use of a continuous upper fabric layer and a continuous lower fabric layer to provide a spring core having a more unitary construction, and referring now to
In some embodiments of the present invention, however, there is no recess in the interior cavity of each coil spring and the cushioning layer extends below the upper end convolution of the coil springs only into the plurality of intermediate recessed between each of the coil springs. For instance, and referring now to
As a further refinement of the spring cores and mattress assemblies of the present invention, rather than the spring core having only one cushioning layer that is positioned atop the continuous upper fabric layer, it is contemplated that the spring core can further includes a second cushioning layer positioned below the continuous lower fabric layer such that both sides of the spring core provide suitable support and distribution of pressure from a user's body, or portion thereof, resting thereon. For example, in another embodiment of the present invention and referring now to
As shown in
As described above, and regardless of the particular configuration of the coil springs and fabric layers utilized in the exemplary spring cores described herein, each of the spring cores are generally produced by making use of a process in which a foam precursor is applied directly to the continuous fabric layer, or layers, covering each of the coil springs. In one exemplary implementation of a method for producing a spring core, such as the spring core 12 described above, and referring now to
Regardless of the particular composition of the foam precursor, by dispensing the foam precursor as a liquid onto the continuous upper layer, the liquid foam precursor is thus capable of not only evenly covering the entirety of the continuous upper fabric layer, but the foam precursor is also capable of completely filling the recesses defined by the continuous upper layer and extending below the upper end convolution of each coil spring into the interior cavity of each coil spring and/or between each coil spring. Then, once applied, a top surface of the foam precursor can be smoothed, as indicated by step 640, by making use of a knife blade edge, or other similar device, to create a planar top surface on the foam precursor and, eventually, the resultant set foam layer (i.e., the cushioning layer). After dispensing and smoothing the foam precursor onto the continuous upper fabric layer, the foam precursor is then allowed to cure and bond to the continuous upper fabric layer such that the foam precursor forms a set foam or cushioning layer, as indicated by step 650. For instance, in some implementations, the coil spring array with the foam precursor can be advanced through an infrared curing oven or can be cured via other means (e.g., humidity, ultraviolet light, etc.) where the time spent in curing the foam is predetermined to adequately cure the foam precursor into the set foam layer. After the foam precursor has reacted for an appropriate amount of time and the foam precursor has set, the edges of the set foam can then be trimmed as desired to produce an exemplary spring core of the present invention that provides the contact feel of foam with the underlying support of a coiled spring.
As a further refinement of the method for producing a spring core, in some implementations, it is contemplated that rather than smoothing the foam precursor prior to curing, the foam precursor can, in some embodiments be allowed to partially cure before rollers are applied to the upper surface of the partially cured foam to provide a smooth upper surface. The foam is then allowed to fully cure and set into the cushioning layer. Furthermore, in some other embodiments the foam precursor is allowed to fully cure and then the set foam is planarized (i.e., an upper portion of the set foam layer is removed) to leave a substantially planar top surface of the cushioning layer.
Of course, in some other exemplary methods for producing a spring core, such as the spring core 412 with a first cushioning layer 440 positioned atop the continuous upper fabric layer 450 and a second cushioning layer 444 positioned below the continuous lower fabric layer 452 described above, the first cushioning layer is formed according to the steps 610-650 outlined above. Then, the spring core with the first cushioning layer already formed is turned over and the second cushioning layer is formed by dispensing foam precursor onto the continuous lower fabric layer, substantially the same as described above with respect to step 630. Then, once applied, a top surface of the foam precursor can be smoothed, substantially the same as described above with respect to step 640. After dispensing and smoothing the foam precursor onto the continuous lower fabric layer, the foam precursor is then allowed to cure and bond to the continuous lower fabric layer such that the foam precursor forms the second cushioning layer, substantially the same as described above with respect to step 650, and the resulting spring core provides the contact feel of foam with the underlying support of a coiled spring on both sides of the spring core.
Throughout this document, various references are mentioned. All such references are incorporated herein by reference, including the references set forth in the following list:
1. U.S. Pat. No. 4,439,977 to Stumpf, issued Apr. 3, 1984, and entitled “Method and Apparatus for Making a Series of Pocketed Coil Springs.”
2. U.S. Pat. No. 4,609,186 to Thoenen, issued Sep. 2, 1986, and entitled “Mattress Spring Core with Open Ended Coils.”
3. U.S. Pat. No. 6,260,223 to Mossbeck et al., issued Jul. 17, 2001, and entitled “Pocketed Coil Spring Units.”
4. U.S. Pat. No. 7,185,379 to Barman, issued Mar. 6, 2007, and entitled “Foam Encased Innerspring with Internal Foam Components (Triple Case).”
5. U.S. Pat. No. 7,805,790 to DeMoss, issued Oct. 5, 2010, and entitled “Foam Springs and Innerspring Combinations for Mattresses.”
6. U.S. Pat. No. 7,908,693 to DeMoss, issued Mar. 22, 2011, and entitled “Coil-in Coil Springs and Innersprings.”
One of ordinary skill in the art will recognize that additional embodiments are also possible without departing from the teachings of the present invention or the scope of the claims which follow. This detailed description, and particularly the specific details of the exemplary embodiments disclosed herein, is given primarily for clarity of understanding, and no unnecessary limitations are to be understood therefrom, for modifications will become apparent to those skilled in the art upon reading this disclosure and may be made without departing from the spirit or scope of the claimed invention.
This Divisional Patent Application claims priority to and benefit of, under 35 U.S.C. § 121, U.S. Divisional patent application having Ser. No. 17/354,498, filed Jun. 22, 2021, which claims priority to and benefit of, under 35 U.S.C. § 121, U.S. Continuation-In-Part patent application having Ser. No. 15/210,780, filed Jul. 14, 2016, which claims priority to U.S. patent application having Ser. No. 14/717,245, now issued as U.S. Pat. No. 9,936,815, filed May 20, 2015, and which claims priority to U.S. Provisional Application Ser. No. 62/005,361, filed May 30, 2014, the entire disclosures of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62005361 | May 2014 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17354498 | Jun 2021 | US |
| Child | 18758771 | US | |
| Parent | 15210780 | Jul 2016 | US |
| Child | 17354498 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14717245 | May 2015 | US |
| Child | 15210780 | US |
