Patent Description:
This invention relates to a comfort layer for bedding and seating products. More particularly, this invention relates to a pocketed spring comfort layer for use in seating or bedding products.

Comfort layers are commonly used in seating or bedding products above/below a core, which may or may not include a spring assembly. Such comfort layers may include foam, fiber and gel products. <CIT> discloses a comfort layer made of pocketed springs. Such spring assemblies may be made of strings of individually pocketed coil springs joined together or multiple coil springs joined together by helical lacing wires.

Comfort layers comprising mini pocketed coil springs have heretofore been a uniform firmness throughout. The mini pocketed coil springs have all been the same.

One desirable feature of known pocketed spring assemblies used as the core of bedding products is edge support, i.e., the perimeter of the pocketed spring assembly being firmer than a central portion of the pocketed spring assembly. Due to users sitting on the edge of a bedding or seating product, additional firmness around the perimeter of the product is desirable. Comfort layers are commonly used in seating or bedding products above/below a central core, which may or may not include a spring assembly. The central core is most commonly a pocketed or un-pocketed spring core, but the central core may be made partially or entirely of foam.

<CIT> and <CIT> each disclose a comfort layer made of pocketed mini coil springs configured to overlay a spring core of a bedding or seating product. Such comfort layers commonly have layers of fabric above below individually pocketed mini coil springs. The fabric is chosen to control air flow between pockets and into and out of the pockets.

One drawback to such pocketed spring comfort layers is that a mattress manufacturer may desire to place one or more foam or fiber layers above such a pocketed spring comfort layer so that a user does not detect or feel the pocketed spring comfort layer. In the case of a double-sided bedding or seating product, a mattress manufacturer may place one or more foam or fiber layers above one pocketed spring comfort layer and below another pocketed spring comfort layer on the opposite surface of the product.

It is therefore an objective of this invention to provide a pocketed spring comfort layer adapted to overlay a spring core of a seating or bedding product which may eliminate or reduce the need for a mattress manufacturer to place one or more foam or fiber layers above the pocketed spring comfort layer and yet obtain the effect of edge support.

It is another objective of this invention to provide a pocketed spring comfort layer adapted to overlay a spring core of a seating or bedding product which may reduce the number or thickness of foam or fiber layers a mattress manufacturer may elect to place above such a pocketed spring comfort layer, thereby reducing the cost of the finished mattress by the cost of such layers and the associated cost of applying them while still obtaining edge support.

It is another objective of this invention to provide a pocketed spring comfort layer for a seating or bedding product which has different regions or sections of different firmness.

Still another objective of this invention has been to provide a pocketed spring comfort layer for a seating or bedding product having edge support around the perimeter of the pocketed spring comfort layer.

The invention, which accomplishes these objectives, comprises a comfort layer to overlay a core of a bedding or seating product as claimed in claim <NUM>. Preferred features of the invention are set out in the dependent claims.

Any of the embodiments of comfort layer shown or described herein may be incorporated into a bedding product, such as a mattress, foundation or pillow. Further, any of the embodiments of comfort layer shown or described herein may be incorporated into a seating product, such as a vehicle seat and/or office or residential furniture, such as a recliner. Alternatively, any of the embodiments of comfort layer shown or described herein may be sold independently as a retail or wholesale item. In such an application, the comfort layer may be added to and/or removed from a bedding or seating product by a customer. Most embodiments of comfort layer are configured to overlay a core of a bedding or seating product such as a pocketed spring core, for example.

In some embodiments, the weld seams are circular and the weld segments are curved. In other embodiments, the weld seams are rectangular and the weld segments straight. In most embodiments, the weld seams and the gaps therebetween are the same size. However, the weld seams may be different sizes.

The comfort layer, whether incorporated inside a bedding or seating product or manufactured and sold as a separate product, comprises a matrix of mini coil springs, a first piece of fabric on one side of the matrix of mini coil springs and a second piece of fabric on another side of the matrix of mini coil springs. The first and second pieces of fabric are joined with weld seams comprising weld segments around each of the mini coil springs to create gaps between the first and second pieces of fabric and individual pockets which contain the mini coil springs. The comfort layer has different sections of different firmness due, at least in part, to the out-of-pocket height of the mini coil springs.

By changing out-of-pocket height and optionally the gauge of wire, number of convolutions/pitch or any combination thereof of the mini coil springs of different section of the comfort layer, a posturized comfort layer may be constructed.

These and other objects and advantages of this invention will be more readily apparent from the following drawings, in which:.

The method of changing firmness in the pairs 3A-4A and 5A-6A, respectively changing the gauge wire and the number of convolutions, is not according to the literal definition of claim <NUM> when implemented alone. However, any of those methods for changing firmness can be implemented in addition to the change of out-of-pocket height, claimed by claim <NUM>.

With reference to <FIG>, there is illustrated a single-sided mattress <NUM> incorporating one embodiment of comfort layer in accordance with this invention. This mattress <NUM> comprises a spring core <NUM> over the top of which there is a conventional cushioning pad <NUM> which may be partially or entirely made of foam or fiber or gel, etc. The cushioning pad <NUM> may be covered by a comfort layer <NUM> constructed in accordance with the invention. A second conventional cushioning pad <NUM> may be located above the comfort layer <NUM>. In some applications, one or both of the cushioning pads <NUM> may be omitted. This complete assembly may be mounted upon a base <NUM> and is completely enclosed within an upholstered cover <NUM>.

As shown in <FIG>, mattress <NUM> has a longitudinal dimension or length L, a transverse dimension or width W and a height H. Although the length L is shown as being greater than the width W, they may be identical. The length, width and height may be any desired distance and are not intended to be limited by the drawings.

While several embodiments of comfort layer are illustrated and described as being embodied in a single-sided mattress, any of the comfort layers shown or described herein may be used in a single-sided mattress, double-sided mattress or seating cushion. In the event any such comfort layer is utilized in connection with a double-sided product, then the bottom side of the product's core may have a comfort layer applied over the bottom side of the core, and either comfort layer may be covered by one or more cushioning pads made of any conventional material. Either the cushioning pad or pads, on top and/or bottom of the core, may be omitted. The novel features of the invention reside in the comfort layer.

Although spring core <NUM> is illustrated being made of unpocketed coil springs held together with helical lacing wires, the core of any of the products, such as mattresses shown or described herein, may be made wholly or partially of pocketed coil springs (see <FIG>), one or more foam pieces (not shown) or any combination thereof. Any of the comfort layers described or shown herein may be used in any single or double-sided bedding or seating product having any conventional core. This document is not intended to limit in any way the core. The core may be any conventional core including, but not limited to, pocketed or conventional spring cores.

<FIG> illustrates the components of one embodiment of comfort layer <NUM> incorporated into the mattress <NUM> shown in <FIG>. The comfort layer <NUM> comprises a first or upper piece of fabric <NUM> and a second or lower piece of fabric <NUM> with a plurality of mini coil springs <NUM>, <NUM> therebetween. The fabric pieces <NUM>, <NUM> are joined together with circular containments or seams <NUM>, each circular seam <NUM> surrounding a mini coil spring <NUM>, <NUM>. Each circular seam <NUM> comprises multiple arced or curved weld segments <NUM> with gaps <NUM> therebetween. The first and second pieces of fabric <NUM>, <NUM> are joined together along each arced or curved weld segment <NUM> of each circular seam <NUM>. The first and second pieces of fabric <NUM>, <NUM> are not joined together along each gap <NUM> between adjacent weld segments <NUM> of each circular seam <NUM>. The curved weld segments <NUM> are strategically placed around a mini coil spring <NUM>, <NUM> and create the circular seam <NUM>. The two pieces of fabric <NUM>, <NUM>, in combination with one of the the circular weld seams <NUM>, define a cylindrical-shaped pocket <NUM>, <NUM> inside of which is at least one mini coil spring <NUM>, <NUM>. See <FIG> and <FIG>.

During the welding process, the mini coil springs <NUM> may be at least partially compressed before pocket <NUM>, <NUM> is closed and thereafter. If desired, resilient members other than mini coil springs, such as foam members, may be used. Alternatively, resilient members made of resilient material, other than foam which returns to its original configuration after a load is removed from the material, may be used inside the pockets.

The size of the curved weld segments <NUM> of circular seams <NUM> are not intended to be limited by the illustrations; they may be any desired size. Similarly, the size, i.e., diameter of the illustrated circular seams <NUM>, is not intended to be limiting. The placement of the circular seams <NUM> shown in the drawings is not intended to be limiting either. For example, the circular seams <NUM> may be organized into aligned rows and columns, as shown in <FIG> and <FIG> or may be organized with adjacent columns being offset from each other, as illustrated in <FIG>. Any desired arrangement of seams may be incorporated into any embodiment shown or described herein.

The weld segments may assume shapes other than the curved weld segments illustrated. For example, the welds or seams may be circular around mini coil springs, but the weld segments may assume other shapes, such as triangles or circles or ovals of the desired size and pattern.

<FIG> illustrates the comfort layer <NUM> having a center section <NUM> and a perimeter section <NUM> surrounding the center section <NUM>. The perimeter section <NUM> has the shape of a picture frame comprising two end sections <NUM> and two side sections <NUM>. The center section <NUM> is generally rectangular shaped and located inside the perimeter section <NUM>.

The center and perimeter sections <NUM>, <NUM>, respectively, have identical pockets <NUM>, <NUM>, respectively, made of the same materials, first and second pieces <NUM>, <NUM> of non-woven polypropylene fabric in one embodiment. Each of the mini coil springs <NUM> of the center section <NUM> may be a "soft" mini coil spring <NUM>, as described below and shown in <FIG>. Each of the mini coil springs <NUM> of the perimeter section <NUM> may be a "firm" mini coil spring <NUM>, as described below and shown in <FIG>. However, the mini coil springs of the center section <NUM> may be any "soft" mini coil springs shown or described herein and the mini coil springs of the perimeter section <NUM> "firm" coil springs.

<FIG> illustrates one "firm" mini coil spring <NUM> used in the perimeter section <NUM> of the comfort layer <NUM> in a relaxed condition. In such a condition, "firm" mini coil spring <NUM> may be approximately <NUM> to <NUM> inches (<NUM>- <NUM>) tall, have a diameter of approximately <NUM> inches (<NUM>) and be made of seventeen-gauge wire. As shown in <FIG> while compressed inside one of the pockets <NUM>, each of the "firm" mini coil springs <NUM> is shorter than when out-of-pocket or in a relaxed condition. In one embodiment, each of the compressed "firm" mini coil springs <NUM> is approximately one inch (<NUM>) tall.

As shown in <FIG>, each "soft" mini coil spring <NUM> in a relaxed condition may be approximately <NUM> to <NUM> inches (<NUM> - <NUM>) tall, have a diameter of approximately <NUM> inches (<NUM>) and be made of nineteen-gauge wire. As shown in <FIG>, being compressed inside one of the pockets <NUM>, each of the "soft" mini coil springs <NUM> is shorter than when out-of-pocket or in a relaxed condition. In one embodiment, each of the compressed "soft" mini coil springs <NUM> is approximately one inch (<NUM>) tall.

As shown in <FIG>, a method of changing the firmness of the mini coil springs according to the invention is to change the out-of-pocket height of the mini coil springs rather than change the wire gauge or the number of convolutions or turns. <FIG> illustrates another mini coil spring <NUM> which, when compared to mini coil spring <NUM> of <FIG>, is a "firm" mini coil spring for use in any firm section of any comfort layer described or shown herein including perimeter section <NUM> of the comfort layer <NUM>. Mini coil spring <NUM> shown in a relaxed or uncompressed condition in <FIG> will be considered a "soft" mini coil spring for use for use in any soft section of any comfort layer described or shown herein including in the center section <NUM> of the comfort layer <NUM>. <FIG> illustrates "firm" mini coil spring <NUM> compressed inside one of the pockets <NUM>, approximately one inch (<NUM>) tall. Likewise, <FIG> illustrates "soft" mini coil spring <NUM> compressed inside one of the pockets <NUM>, approximately one inch (<NUM>) tall.

As shown in <FIG>, another method of changing the firmness of the mini coil springs is to change the number of convolutions or turns of the mini coil spring rather than change the wire gauge or the out-of-pocket height. <FIG> illustrates another mini coil spring <NUM> which, when compared to mini coil spring <NUM> of <FIG>, will be considered a "firm" mini coil spring for use in any firm section of any comfort layer described or shown herein including the perimeter section <NUM> of the comfort layer <NUM>. Mini coil spring <NUM> shown in a relaxed or uncompressed condition in <FIG> will be considered a "soft" mini coil spring for use in any soft section of any comfort layer described or shown herein including the center section <NUM> of the comfort layer <NUM>. <FIG> illustrates "firm" mini coil spring <NUM> compressed inside one of the pockets <NUM>, approximately one inch (<NUM>) tall. Likewise, <FIG> illustrates "soft" mini coil spring <NUM> compressed inside one of the pockets <NUM>, approximately one inch (<NUM>) tall.

Any of the spring characteristics such as wire gauge, number of convolutions or any combination thereof may be used to differentiate mini-coil springs, besides the out-of-pocket height the firmer mini coil springs being used in the firmer sections of any comfort layer shown or described herein and the softer mini coil springs being used in the softer sections of any comfort layer shown or described herein.

Any of the mini coil springs shown or described herein in a relaxed condition may be any desired height, have any desired shape, such as an hourglass or barrel shape, and be made of any desired wire thickness or gauge and have any number of convolutions. The drawings are not intended to be limiting.

In the embodiments in which the fabric material of pieces <NUM>, <NUM> defining pockets <NUM>, <NUM> and enclosing the mini coil springs <NUM>, <NUM> therein is semi-permeable to airflow, upon being subjected to a load, a pocket <NUM>, <NUM> containing at least one mini coil spring <NUM>, <NUM> is compressed by compressing the mini coil spring(s) <NUM>, <NUM> contained within the pocket(s) <NUM>, <NUM>.

As best illustrated in <FIG>, the individual pockets <NUM>, <NUM> of comfort layer <NUM> may be arranged in longitudinally extending columns <NUM> extending from head-to-foot of the bedding product and transversely extending rows <NUM> extending from side-to-side of the bedding product. As shown in <FIG> and <FIG>, the individual pockets <NUM>, <NUM> of one column <NUM> are aligned with the pockets <NUM>, <NUM> of adjacent columns <NUM>.

<FIG> illustrate a center section of another comfort layer <NUM> having the same pockets <NUM> and same mini coil springs <NUM> as does the embodiment of comfort layer <NUM> of <FIG>. As best illustrated in <FIG>, the individual pockets <NUM> of comfort layer <NUM> are arranged in longitudinally extending columns <NUM> extending from head-to-foot of the bedding product and transversely extending rows <NUM> extending from side-to-side of the bedding product. As shown in <FIG>, the individual pockets <NUM> of one column <NUM> are offset from, rather than aligned with, the pockets <NUM> of the adjacent columns <NUM>.

<FIG> illustrates an alternative embodiment of comfort layer <NUM> incorporated into a single-sided mattress <NUM>. Single-sided mattress <NUM> comprises a pocketed spring core <NUM>, a cushioning pad <NUM> on top of the pocketed spring core <NUM>, a base <NUM>, another cushioning pad <NUM> above comfort layer <NUM>, and an upholstered covering material <NUM>. Pocketed spring core <NUM> may be incorporated into any bedding or seating product, including a double-sided mattress, and is not intended to be limited to single-sided mattresses. As described above, at least one comfort layer <NUM> may be used in any conventional core, including a spring core made with non-pocketed conventional springs. At least one comfort layer <NUM> may be used in any single or double-sided bedding or seating product.

<FIG> illustrate the components of the comfort layer <NUM> incorporated into the mattress <NUM> shown in <FIG>. The comfort layer <NUM> comprises a first piece of fabric <NUM> and a second piece of fabric <NUM> joined together with multiple intersecting linear seams <NUM>. Each linear seam <NUM> comprises multiple linear weld segments <NUM>. These linear weld segments <NUM> are strategically placed around a mini coil spring <NUM> and create a rectangular pocket <NUM>. During the welding process, the mini coil springs <NUM>, <NUM> may be compressed. The length and/or width of the linear weld segments <NUM> of linear seams <NUM> is not intended to be limited to those illustrated; they may be any desired size. Similarly, the size of the illustrated linear seams <NUM> is not intended to be limiting. Shapes other than linear weld segments may be used to create rectangular seams. Such shapes may include, but are not limited to, triangles or circles or ovals of any desired size.

In some embodiments, the fabric material defining pockets <NUM> and enclosing the mini coil springs <NUM>, <NUM> therein is semi-permeable to airflow. In accordance with the practice of this invention, one fabric material semi-impermeable to airflow, which may be used in either of the two pieces of the pocketed spring comfort layers disclosed or shown herein, may be a multi-layered material.

As best illustrated in <FIG>, the individual pockets <NUM> of comfort layer <NUM> may be arranged in longitudinally extending columns <NUM> extending from head-to-foot of the bedding product and transversely extending rows <NUM> extending from side-to-side of the bedding product. As shown in <FIG>, the individual pockets <NUM> of one column <NUM> are aligned with the pockets <NUM> of the adjacent columns <NUM>.

<FIG> illustrates another posturized comfort layer <NUM> having three different areas or regions of firmness depending upon the airflow within each of the areas or regions. The comfort layer <NUM> has a head section <NUM>, a foot section <NUM> and a lumbar or middle section <NUM> therebetween. The size and number of segments in the seams, along with the type of material used to construct the posturized comfort layer <NUM>, may be selected so at least two of the sections may have a different firmness due to different springs within different sections. Although three sections are illustrated in <FIG>, any number of sections may be incorporated into a posturized comfort layer. Although each of the sections is illustrated being a certain size, they may be other sizes. The drawings are not intended to be limiting. Although <FIG> shows each of the segmented seams of comfort layer <NUM> being circular, posturized comfort layer <NUM> may have rectangular segmented seams, such as the rectangular segmented seams shown in <FIG>.

<FIG> illustrates another posturized comfort layer <NUM> having two different areas or regions of firmness depending upon the mini coil springs within each of the areas or regions. The comfort layer <NUM> has a first section <NUM> and a second section <NUM>. The size and number of segments in the seams, along with the type of material used to construct the posturized comfort layer <NUM>, may be selected so at least two of the sections may have a different firmness due to different mini coil springs within different sections. Although two sections are illustrated in <FIG>, any number of sections may be incorporated into a posturized comfort layer. Although each of the sections is illustrated being a certain size, they may be other sizes. The drawings are not intended to be limiting. Although <FIG> shows each of the segmented seams of comfort layer <NUM> being circular, posturized comfort layer <NUM> may have rectangular or square segmented seams, such as the seams shown in <FIG>.

<FIG> illustrates another posturized comfort layer <NUM> having two different areas or regions of firmness depending upon the mini coil springs within each of the areas or regions. The comfort layer <NUM> has two rectangular soft sections <NUM> and a firm section <NUM> therebetween. In addition, a perimeter section <NUM> extending around the perimeter is the same firmness as the firm section <NUM>. The perimeter section <NUM> comprises two end sections <NUM> and two side sections <NUM>. The size and number of segments in the seams, along with the type of material used to construct the posturized comfort layer <NUM>, may be selected so at least two of the sections may have a different firmness due to different mini coil springs within different sections. Although three sections are illustrated in <FIG>, any number of sections may be incorporated into a posturized comfort layer. Although each of the sections is illustrated being a certain size, they may be other sizes. The drawings are not intended to be limiting. Although <FIG> shows each of the segmented seams of comfort layer <NUM> being circular, the posturized comfort layer <NUM>, may have rectangular segmented seams, such as the rectangular seams shown in <FIG>.

Claim 1:
A comfort layer (<NUM>; <NUM>; <NUM>; <NUM>) configured to overlay a core of a bedding or seating product, said comfort layer (<NUM>; <NUM>; <NUM>; <NUM>) comprising:
a matrix of mini coil springs (<NUM>, <NUM>; <NUM>);
a first piece of fabric (<NUM>; <NUM>) on one side of the matrix of mini coil springs (<NUM>, <NUM>; <NUM>);
a second piece of fabric (<NUM>; <NUM>) on another side of the matrix of mini coil springs (<NUM>, <NUM>; <NUM>), the first and second pieces of fabric being joined with weld seams comprising weld segments around each of the mini coil springs (<NUM>, <NUM>; <NUM>) to create gaps between the first (<NUM>; <NUM>) and second (<NUM>; <NUM>) pieces of fabric and individual pockets which contain the mini coil springs (<NUM>, <NUM>; <NUM>);
said comfort layer (<NUM>; <NUM>; <NUM>; <NUM>) having different sections of different firmness due, at least in part, to the out-of-pocket height of the mini coil springs (<NUM>, <NUM>; <NUM>).