U.S. patent application number 15/729722 was filed with the patent office on 2018-05-10 for mattresses having a matrix core of foam elements.
The applicant listed for this patent is Denver Mattress Co., LLC. Invention is credited to Bob Rensink.
Application Number | 20180125258 15/729722 |
Document ID | / |
Family ID | 48222688 |
Filed Date | 2018-05-10 |
United States Patent
Application |
20180125258 |
Kind Code |
A1 |
Rensink; Bob |
May 10, 2018 |
MATTRESSES HAVING A MATRIX CORE OF FOAM ELEMENTS
Abstract
A mattress is constructed of a core comprising a matrix of foam
pieces that are bonded together. The core has a thickness in the
range from about 1.5 inches to about 10 inches, and more
particularly from about 3 inches to about 8 inches, a density of
about 4 pounds to 8 pounds per cubic foot, and an IFD of about 28
to 65. The core has a top surface and a bottom surface. A base
layer is coupled to the bottom surface of the core, and a cushion
layer is coupled to the top surface.
Inventors: |
Rensink; Bob; (Denver,
CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Denver Mattress Co., LLC |
Denver |
CO |
US |
|
|
Family ID: |
48222688 |
Appl. No.: |
15/729722 |
Filed: |
October 11, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13666253 |
Nov 1, 2012 |
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15729722 |
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61554413 |
Nov 1, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A47C 27/15 20130101;
Y10T 29/49826 20150115 |
International
Class: |
A47C 27/15 20060101
A47C027/15 |
Claims
1-15. (canceled)
16. A mattress comprising: a core comprising a matrix of foam
pieces that are adhesively bonded together by coating the foam
pieces with a binder or resin and compressing the foam pieces to a
desired density up to 8 pounds per cubic foot, wherein the core has
a thickness in the range from 3 inches to about 10 inches, and an
IFD of about 28 to 65, the core having a top surface and a bottom
surface; a cushion layer coupled to the top surface, wherein the
cushion layer comprises a polyurethane foam or latex, has a density
in the range from about 2 pounds per cubic foot to about 6 pounds
per cubic foot, a height in the range from 2 inches to about 6
inches and an IFD of about 6 to about 18; and a base layer coupled
to the bottom surface of the core, the base layer comprising a
support foam layer having a thickness in the range from 0.25 inch
to 2 inches with a density of about 1 pound per cubic foot to about
2 pounds per cubic foot and an IFD of about 28 to about 70.
17. The mattress of claim 16, wherein the core thickness ranges
from 4 inches to about 8 inches.
18. The mattress as in claim 16, wherein the cushion layer
comprises a visco-elastic material.
19. The mattress as in claim 16, further comprising a top layer
positioned above the cushion layer.
20. The mattress as in claim 16, further comprising a cover
enveloping the core, the base layer and the cushion layer.
21. The mattress as in claim 20, wherein the cover is quilted.
22. The mattress as in claim 20, wherein the cover has flame
retardant or flare resistant features.
23. The mattress as in claim 16, wherein the foam pieces comprise
polyurethane, urethane, or a combination thereof.
24. A mattress comprising: a core comprising a matrix of foam
pieces that are adhesively bonded together by coating the foam
pieces with a binder or resin and compressing the foam pieces to a
density of between about 4 pounds per cubic foot to about 8 pounds
per cubic foot, wherein the core has a thickness in the range from
3 inches to about 8 inches, and an IFD of about 28 to 65, the core
having a top surface and a bottom surface, wherein each of the foam
pieces ha a size in the range of about 0.25 inch by about 0,25 inch
by about 0.25 inch to about 3 inches by about 3 inches by about 1
inch; a cushion layer coupled to the top surface, wherein the
cushion layer comprises air insulated viscofoam, has a density in
the range from about 2 pounds per cubic foot to about 6 pounds per
cubic foot, a height in the range from 2 inches to about 6 inches
and an IFD of about 6 to about 18; and a base layer coupled to the
bottom surface of the core, the base layer comprising a support
foam layer having a thickness in the range from 0.25 inch to 2
inches with a density of about 1 pound per cubic foot to about 2
pounds per cubic foot and an IFD of about 28 to about 70.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 61/554,413, filed Nov. 1, 2011, titled
"Mattresses Having a Matrix Core of Foam Elements," the entire
contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to the field of mattresses.
In particular, the invention relates to mattress that utilize a
core made up of a matrix of foam elements.
[0003] Spring mattresses have been in use for over 100 years.
Existing spring mattresses use a variety of spring types to form
their inner core. Perhaps the most common is the traditional wire
spring assembly having a set of interconnected wire spring
coils.
[0004] As manufacturing processes have improved, it is becoming
more common to use other types of cores, including cores made of a
single material, such as a core constructed from a solid piece of
latex or polyurethane.
[0005] This invention relates to mattress using other types of
cores. Such cores take advantage of reclaimed or repurposed
materials that would otherwise be discarded (e.g., as being
unusable cut sizes or foam densities after foam manufacturing
runs).
BRIEF SUMMARY OF THE INVENTION
[0006] In one embodiment, the invention provides a mattress that is
constructed of a core comprising a matrix of foam pieces that are
bonded together. The core has a thickness in the range from about
1.5 inches to about 10 inches, and more particularly from about 3
inches to about 8 inches, a density of about 4 pounds to 8 pounds
per cubic foot, and an Indentation Force Deflection (IFD) of about
28 to 65. For convenience of discussion, the core may have a top
surface and a bottom surface. A base layer is coupled to the bottom
surface of the core, and a cushion layer is coupled to the top
surface. In this way, remnant foam pieces that may otherwise be
discarded may be used to form a relatively dense mattress core. For
example, the foam pieces may comprise polyurethane, urethane and
the like.
[0007] In one aspect, the cushion layer comprises a visco-elastic
material. In another aspect, a top layer is positioned above the
cushion layer. A flame or fire retardant sock (referred to as an FR
sock) may also be provided to enclose the completed mattress. Per
regulations, this provides a covering for the mattress that meets
an open flame standard. Alternatively, a flame retardant or
resistant fiber layer may be provided below quilting if desired.
Further, a cover, also known as a ticking, is typically employed to
envelope the core, the base layer and the cushion layer. The cover
may also be either quilted (to form a pillow top mattress), a plush
quilted or non-quilted.
[0008] In a further embodiment, the invention provides an exemplary
method for constructing a mattress. In one step of the process, a
loaf is formed by combining a plurality of foam pieces and a
bonding material into a generally rectangular mold and applying
heat. In this way, the resulting loaf has a top, a bottom and four
sides. To form a core, a rectangular section is cut from the loaf,
and will typically have a thickness in the range from about 3
inches to about 8 inches. The resulting core may have a density in
the range from about 4 pounds to about 8 pounds and an IFD in the
range from about 28 to about 65. A base layer is attached to a
bottom surface of the core, and a cushion layer is attached to a
top surface of the core. Typically, a cover is placed about the
mattress.
[0009] The mattresses described herein may be useful as mattresses
for conventional beds, but they may also be useful for mattresses
used with a sleeper sofa, camper beds, yacht beds, cruise-ships
beds, play mats, gym mats, camping pads, nap pads, or any other
potential use where a core with a padded surface may be desirable.
The term "mattress" as used herein is intended to encompass these
and other appropriate uses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 illustrates a schematic cross sectional side view of
one embodiment of a mattress according to the invention.
[0011] FIG. 2 is an exploded schematic top perspective view of the
mattress of FIG. 1, showing various component layers, not
necessarily to scale.
[0012] FIG. 3 illustrates a schematic cross sectional side view of
another embodiment of a mattress according to the invention.
[0013] FIG. 4 illustrates a mattress according to one of the
embodiments described herein, with a layer of ticking disposed over
the foam core, base layer, and cushion layer.
[0014] FIG. 5 illustrates a cross-sectional view of another
mattress according to one embodiment of the invention.
[0015] FIG. 6 illustrates the mattress of FIG. 5, having various
component layers rolled back at one corner.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Embodiments of the invention provide various mattress that
utilize a core made up of a matrix of foam pieces or elements that
are bonded together. The core is relatively dense, significantly
more dense than traditional polyurethane cores. This increased
density provides a stronger and more durable core while providing a
more comfortable feel. Another significant advantage of using a
matrix of foam pieces is that such foam pieces may be repurposed or
otherwise reclaimed materials. Not only is this friendly to the
environment, it also significantly reduces the cost of the
mattress.
[0017] Hence, the core may be constructed to have a high density
along with a durable construction to provide increased life. This
matrix of foam pieces is also firm and is constructed of a variety
of small urethane or other foam pieces (typically re-purposed foam
pieces, for example new foam that cannot be cut into other pieces
of the desired size or sections of foam that are not the desired
density for other purposes, allowing the foam to be re-purposed in
a new fashion) that are joined together using an adhesive, heat and
steam that tend to increase the density. One particularly useful
method for constructing cores using such a process is described
hereinafter.
[0018] Further, the core may be constructed to be relatively dense,
has an IFD in the range from about 28 to about 65 and is relatively
inexpensive. Other types of materials that may be used include
polystyrene materials, polyurethane, densified fibers and the like.
The IFD, or Indentation Force Deflection, refers to the hardness or
softness of the foam. For example, the higher the IFD, the firmer
the foam. IFD is defined as the amount of force, in pounds,
required to indent a fifty square inch, round indentor foot into a
predefined foam specimen a certain percentage of the specimen's
total thickness. IFD is specified as a number of pounds at a
specific deflection percentage on a specific height foam sample,
e.g., 25 pounds applied to 50 square inches at a 25% deflection on
a four inch thick piece.
[0019] A wide variety of optional layers may be coupled to the top
and/or bottom surface of the core. For example, another dense foam
material may be coupled to the bottom of the core. A variety of
layers may be placed on top of the core, including additional
padding layers, ticking, foam, a quilted layer, or the like.
[0020] In some embodiments, one or more cushion layers may be
placed above the core. These may be constructed of a material such
as a polyurethane or latex foam, a visco-elastic or memory foam
material, or the like. These additional padding layers may be used
to provide the mattress with additional comfort and may be used
alone or in various combinations. One or both sides of these
cushion layers may be surface modified using various machining
processes. Examples of surface modifications include convoluted,
contoured, and the like. Other materials that may be used include
fiber padding materials. Further, mattresses of the invention may
include a layer of ticking that is a piece of fabric or quilting
that envelopes the mattress as is known in the art. The ticking may
comprise essentially any type of fabric or covering and may be sewn
to form it around the core and other padding layers.
[0021] Referring now to FIGS. 1 and 2, one embodiment of a mattress
10 will be described. Mattress 10 includes a core 12 that is
constructed of a plurality of foam pieces that are bonded together
to form a matrix. Core 12 typically has a thickness in the range
from about 3 inches to about 8 inches, but may range anywhere from
1.5 inches to about 10 inches. One specific embodiment has a core
that is about 4.5 inches to about 7.5 inches. In a particular
embodiment, the core thickness may range from about 3 inches to
about 5 inches, and may specifically be about 4.5 inches. In an
alternate embodiment, the core thickness may range from about 4
inches to about 6 inches, and may specifically be about 5.5 inches.
In a further embodiment, the core thickness may range from about 6
inches to about 8 inches, and may specifically be about 7.5 inches.
The core should be thick enough to provide appropriate support for
sleeping and/or otherwise supporting one or more people, but should
be thin enough that the mattress does not become unwieldy to
transport or so large that sheets are difficult to secure in place
about the mattress.
[0022] The core may also have a density of about 4 pounds to 8
pounds per cubic foot, and an IFD of about 28 to 65. The density
may be varied based upon the size and number of foam pieces used,
as well as the type of binder used. Core 12 has a top surface 14
and a bottom surface 16. One example showing how smaller foam
pieces may be bonded to one another in order to form core 12 is
shown in FIG. 5, and such methods of manufacture are described
further below.
[0023] Coupled to bottom surface 16 may be a base layer 18. The two
may be coupled together by glue, a bonding material or the like.
Base layer 18 will typically be a piece of foam that is less dense
than core 12 and may have a thickness in the range from about 0.25
inch to about 4 inches. In a particular embodiment, the base layer
thickness may range from about 0.5 to about 2 inches, and may
specifically be about one inch. The density may be in the range
from about 1 pound per cubic foot to about 2 pounds per cubic foot,
with an IFD of about 28 to about 70. Base layer 18 in some cases
serves to help hold together the foam pieces in the matrix, thus
increasing the life of the mattress.
[0024] Secured to top surface 16 is a cushion layer 20. One
exemplary material that may be used to construct cushion layer is a
visco-elastic foam, gel viscoelastic foam, air ventilated viscofoam
with enhanced breathing properties, memory foam, down feathers,
synthetic down alternative, latex, any combination thereof, or any
other appropriate cushion-like surface that adds comfort and
padding to the mattress. The cushion layer 20 may be formed as a
combination of one or more comfort layers. The density of this
cushion layer may be in the range from about 2 pounds per cubic
foot to about 6 pounds per cubic foot. In a particular embodiment,
the density may range from about 2 pounds per cubic foot to about 5
pounds per cubic foot, and may specifically be about 3 pounds per
cubic foot or about 3.5 pounds per cubic foot. The height of the
cushion layer may be about 1 inch to about 6 inches, more
specifically from about 1 inch to about 5 inches, and more
specifically, from about 2 inches to about 4.5 inches, and even
more particularly, about 4.5 inches. The cushion layer may have an
IFD rating of about 6 to about 18. FIGS. 1 and 2 show a single
layer of visco-elastic foam, and FIGS. 5 and 6 show other
embodiments having multiple layers of visco-elastic foam or other
cushion-like material. Cushion layer may also be a combination of
air insulated viscofoam with enhanced ventilating properties so
that it breathes more and keeps the sleeper cooler.
[0025] The various layers may have different densities and or IFD
ratings. As shown in FIG. 5, in a particular embodiment with the
cushion layer formed of two layers, one layer 20 may be a
visco-elastic memory foam and another layer 24 may be a second
visco-elastic memory foam layer or a gel visco-elastic memory foam
layer. The first lower visco-elastic memory foam layer may be about
3 to about 3.5 inches thick and may have a density of about 3 to
about 3.5 pounds per cubic foot. The second upper visco-elastic
memory foam layer or gel visco-elastic memory foam layer may be
about 1 to about 1.5 inches thick. Providing two layers in the
cushion layer can add additional comfort to the mattress.
[0026] A flame or fire retardant sock (referred to as an FR sock)
may also be provided to enclose the completed mattress. Per
regulations, this provides a covering for the mattress that meets
an open flame standard. Alternatively, a flame retardant or
resistant fiber layer may be provided below quilting if desired. A
cover ticking 22 may be used to envelop the mattress. Ticking 22
comprises a fabric that is secured about the various layers. FIG. 4
shows a mattress that has been enveloped by a layer of ticking
22.
[0027] As shown in FIG. 3, various other layers may be provided on
mattress 10 to change the look and feel of the mattress. These
could be included beneath the ticking 22, such as with layer 24, or
above ticking 22, such as in the case of an independent topper 26.
These additional layers may be surface modified, such as
convoluted. Examples of materials that may be used for the
additional layers include latex, gel materials, fibrous spacer
materials, that may optionally include a gel material, and the
like. Also, various backing materials and fire resistant layers or
materials may be used as well.
[0028] To construct core 12, multiple foam pieces are used. These
may be of various shapes and sizes. Merely by way of example, these
foam pieces may have a size in the range from about 0.25 inch by
about 0.25 inch by about 0.25 inch to about 3 inches by about 3
inches by about 1 inch. Often, these may be pieces or remnants from
other applications that can be repurposed rather than discarded.
This often leads to the various sizes of pieces that may be used.
For example, various pieces of remnant foams may be collected, then
shredded down to smaller pieces. The individual pieces then need to
be coated with a binder or resin, such as a polyurethane binder.
This may be performed by feeding the pieces into a large container
where the foam pieces are sprayed or otherwise mixed with the
binder.
[0029] After the pieces are coated with the binder, they are fed
into a mold. To facilitate the construction of a core that is to be
used for a mattress, the foam pieces are placed within a
rectangular mold. This mold may have various sizes depending on the
desired size of the mattress. Merely by way of example, the mold
may have a size in the range from about 60 inches by about 80
inches, with a height of about 3 feet to 4 feet. For larger
mattresses, multiple cores may be bonded together. For example, two
cores that are the size of a twin mattress could be bonded together
at their sides to obtain the size and shape of a king sized
mattress. A compression member that may be driven by a piston is
used to compress the foam pieces to the desired density within the
mold. Also, it will be appreciated that the density of the
individual pieces will also contribute to the resulting density.
The mold is then subjected to steam to cure the binder and allowed
to cool. The resulting loaf is removed from the mold and has a
rectangular shape. This loaf may be sliced into multiple layers in
order to form separate cores. Additional timing to size may also be
performed.
[0030] Mattresses made according to the various embodiments
described herein were subjected to various tests in order to
determine the firmness and fatigue resistance of the mattresses.
The tests conducted are general protocol in the bedding industry.
First, the firmness of the mattress is scanned and measured prior
to any fatigue test. For this test, a 15'' circular plate is
depressed into the bed in about nine locations, and the pounds of
pressure required for the plate to press 75% into the mattress is
measured. The plate then moves to 25% depression, which gives the
IFD (indentation force deflection). Next, a rollator (which is a 3
foot, six-sided, 230 pounds log) rolls back and forth across center
of mattress for about 10,000 cycles. The mattress rests 24 hours
and is scanned, which electronically measures any loss/gain of
height. The IFD test is conducted again as well. Additional cycles
of 25,000 cycles, 50,000 cycles, 75,000 cycles and 100,000 cycles
are run, repeating the rest, scan & IFD test. It is believed
that about 100,000 cycles approximates 10 years of use.
[0031] Exemplary results for selected tests are outlined below.
Mattress type: Green Choice Elegant 11'' (Core: 6.5 inches +1 inch
support foam layer as base layer; cushion layer: 3.5 inches (1.5
inch air insulated viscofoam with ventilating properties+2 inches
of regular viscofoam above core)
TABLE-US-00001 Pre test 5k 10k 25k 50k 75k 100k Recovery test
Deflection 4.73 4.46 4.40 4.43 4.43 4.30 4.33 4.30 Load 175 175 175
175 175 175 175 175 Firmness (lb/in) 37.0 39.2 39.8 39.5 39.5 40.7
40.4 40.7 Height change 0.05 0.06 0.13 0.12 0.12 0.13 0.14 (in
inches) Height % change 0.4% 0.5% 1.1% 1.0% 1.0% 1.1% 1.2%
Mattress type: Green Choice Bliss 10'' (Core: 4.5'' ES Core+1''
support foam; cushion layer: 3.5'' 3 lbs ViscoElas Memory Foam+1''
ViscoElas Memory Foam topper)
TABLE-US-00002 pretest 5k 10k 25k 50k 75k 100k Recovery test
Deflection 4.76 4.8 4.7 4.6 4.5 4.6 4.7 4.5 Load 175 175 175 175
175 175 175 175 Firmness (lb/in) 37 37 38 38 39 38 38 39 Height
change 0.13 0.10 0.02 0.08 0.08 0.09 -0.01 (in inches) Height %
change 1.3% 1.0% 0.3% 0.8% 0.9% 0.9% -0.1%
Mattress type: Green Choice Relaxation 11'' (Core: 5.5'' ES
Core+1'' support foam; cushion layer: 3'' 3 lbs ViscoElas Memory
Foam+1.5'' Gel ViscoElas Memory Foam topper)
TABLE-US-00003 pretest 5k 10k 25k 50k 75k 100k Recovery test
Deflection 5.53 5.4 5.3 5.2 5.3 5.3 5.0 5.0 Load 175 175 175 175
175 175 175 175 Firmness (lb/in) 32 32 33 34 33 33 35 35 Height
change .03 -0.05 -0.01 0.04 0.04 0.01 -0.05 (in inches) Height %
change 0.3% -0.4% -0.1% 0.4% 0.4% 0.1% -0.6%
[0032] The invention has now been described in detail for purposes
of clarity and understanding. However, it will be appreciated that
certain changes and modifications may be practiced within the scope
of the appended claims.
* * * * *