U.S. patent application number 09/742126 was filed with the patent office on 2001-07-19 for bed construction with reduced sagging.
Invention is credited to Gladney, Rick F., Kinde, Douglass D., Llng, Kurtis.
Application Number | 20010008030 09/742126 |
Document ID | / |
Family ID | 27047336 |
Filed Date | 2001-07-19 |
United States Patent
Application |
20010008030 |
Kind Code |
A1 |
Gladney, Rick F. ; et
al. |
July 19, 2001 |
Bed construction with reduced sagging
Abstract
A bed construction having a one-sided mattress assembly
supported on a rigid foundation. The one-sided mattress assembly
includes a core of pocketed coil springs having a layer of
resiliently compressible material covering the upper surface
thereof and having a bottom surface constructed of a substantially
rigid material without a compressible layer. The core of coil
springs is attached to the bottom surface around its periphery. The
foundation has a rigid inner construction and a noncompressible top
layer. The bed construction reduces the amount of compressible
padding in the mattress by one-half and consequently the mattress
is capable of exhibiting a substantial reduction in the amount of
permanent deflection in use.
Inventors: |
Gladney, Rick F.; (Fairburn,
GA) ; Llng, Kurtis; (Alpharetta, GA) ; Kinde,
Douglass D.; (Alpharetta, GA) |
Correspondence
Address: |
SMITH, GAMBRELL & RUSSELL, LLP
SUITE 3100, PROMENADE II
1230 PEACHTREE STREET, N.E.
ATLANTA
GA
30309-3592
US
|
Family ID: |
27047336 |
Appl. No.: |
09/742126 |
Filed: |
December 22, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09742126 |
Dec 22, 2000 |
|
|
|
09482591 |
Jan 13, 2000 |
|
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Current U.S.
Class: |
5/720 |
Current CPC
Class: |
A47C 27/05 20130101;
A47C 23/0431 20130101; A47C 27/056 20130101; A47C 27/064
20130101 |
Class at
Publication: |
5/720 |
International
Class: |
A47C 023/04 |
Claims
What is claimed is:
1. A one-sided inner spring mattress assembly comprising: a central
core comprising a wire spring assembly; an upper padding layer
extending over a top surface of the core; and a lower relatively
rigid layer underlying the core, wherein the lower layer is a high
density foam that is resistant to compaction by the central core of
springs.
2. The mattress assembly of claim 1 wherein the lower layer has a
firmness of greater than 30 ILD.
3. The mattress assembly of claim 2 wherein the lower layer has a
density of approximately 1.85 lbs./cu. ft. and a firmness of
approximately 55 ILD.
4. The mattress assembly of claim 1 wherein the central core
comprises pocketed springs.
5. The mattress assembly of claim 1 wherein the core is surrounded
by a lower border wire and is secured to said lower layer by
attaching said border wire to said lower layer.
6. A one-sided inner spring mattress assembly comprising: a central
core comprising a wire spring assembly; an upper padding layer
extending over a top surface of the core; and a lower relatively
rigid layer underlying the core, wherein the lower layer is a solid
plastic material that is resistant to compaction by the central
core of springs and wherein the core is surrounded by a lower
border wire and is secured to said lower layer by attaching said
border wire to said lower layer.
7. The mattress assembly of claim 6 wherein the lower layer has a
firmness of greater than 30 ILD.
8. The mattress assembly of claim 7 wherein the lower layer has a
density of approximately 1.85 lbs./cu. ft. and a firmness of
approximately 55 ILD.
9. The mattress assembly of claim 6 wherein the central core
comprises pocketed springs.
10. A bed construction comprising: a one-sided inner spring
mattress assembly comprising: a central core comprising a wire
spring assembly; an upper padding layer extending over a top
surface of the core; a lower relatively rigid layer underlying the
core; wherein the lower layer is a high density foam that is
resistant to compaction by the central core of springs, and a rigid
foundation for supporting the mattress.
11. The mattress assembly of claim 10 wherein the lower layer has a
firmness of greater than 30 ILD.
12. The mattress assembly of claim 11 wherein the lower layer has a
density of approximately 1.85 lbs./cu. ft. and a firmness of
approximately 55 ILD.
13. The mattress assembly of claim 10 wherein the central core
comprises pocketed springs.
14. The mattress assembly of claim 10 wherein the core is
surrounded by a lower border wire and is secured to said lower
layer by attaching said border wire to said lower layer.
15. A bed construction comprising: a one-sided inner spring
mattress assembly comprising: a central core comprising a wire
spring assembly; an upper padding layer extending over a top
surface of the core; a lower relatively rigid layer underlying the
core; wherein the lower layer is a solid plastic material that is
resistant to compaction by the central core of springs and wherein
the core is surrounded by a lower border wire and is secured to
said lower layer by attaching said border wire to said lower layer,
and a rigid foundation for supporting the mattress.
16. The mattress assembly of claim 15 wherein the lower layer has a
firmness of greater than 30 ILD.
17. The mattress assembly of claim 16 wherein the lower layer has a
density of approximately 1.85 lbs./cu. ft. and a firmness of
approximately 55 ILD.
18. The mattress assembly of claim 15 wherein the central core
comprises pocketed springs.
Description
[0001] Related Applications
[0002] This application is a continuation in part of Ser. No.
09/482,591, filed Jan. 13, 2000, which is incorporated herein by
reference in its entirety.
BACKGROUND OF THE INVENTION
[0003] The present invention relates generally to a bed
construction, and more particularly to a bed construction having a
one-sided mattress assembly supported on a rigid foundation that
offers significant reduction in the amount of permanent deflection
or sagging of sleeping surface of the mattress.
[0004] A conventional inner spring mattress as known in the bedding
industry generally comprises a resilient construction consisting of
two sleep surfaces (a top layer and a bottom layer) enclosing an
assembly of wire springs. The wire springs are typically covered
with padding layers on the top and bottom surfaces, and the whole
assembly is encased within a ticking, often quilted, that is sewn
closed around its periphery to a border or boxing. For many years,
one form of spring assembly construction has been known as Marshall
construction. In Marshall construction, individual wire coils are
each encapsulated in fabric pockets and attached together in
strings which are arranged to form a closely packed array of coils
in the general size of the mattress. Examples of such construction
are disclosed in U.S. Pat. No. 685,160, U.S. Pat. No. 4,234,983,
U.S. Pat. No. 4,234,984, U.S. Pat. No. 4,439,977, U.S. Pat. No.
4,451,946, U.S. Pat. No. 4,523,344, U.S. Pat. No. 4,578,834, U.S.
Pat. No. 5,016,305 and U.S. Pat. No. 5,621,935, the disclosures of
which are incorporated herein by reference in their entireties.
[0005] Conventionally, inner spring mattresses, with either
pocketed coils or open coils, have had identical top and bottom
layers. During normal life of such conventional mattresses some
degree of permanent deflection, or sag, can develop in the mattress
surfaces due to compaction of the component padding materials in
the top and bottom layers. This permanent deflection can interfere
with the mattresses' intended function of providing a supportive
and resilient sleep surface. Inner spring mattress manufacturers
recommend periodically rotating and turning over the mattress
thereby utilizing the top and bottom sleep surfaces in order to
counteract, minimize, and/or delay the aforementioned permanent
deflection or sag. Under continued use, this compaction or sag
becomes more permanent. The degree of permanent deflection is
directly related to the type and amount of padding installed both
over and under the wire spring core assembly. To remedy this
shortcoming, manufacturers utilize materials that produce less
permanent compaction. These materials are generally more dense but
can be less comfortable and more expensive.
[0006] Conventional foundations, such as box springs, often
contributed to the problem of sagging by providing a compressible
top layer. Any additional compaction of the top layer of the
foundation contributes to the overall sagging of the sleeping
surface of the mattress.
[0007] Accordingly, it is desirable to provide a bed construction
having an inner spring mattress assembly which exhibits a reduced
amount of permanent deflection due to compaction of padding
materials while at the same time exhibiting substantial comfort in
use. It is further desirable to provide a mattress assembly that
can be constructed by conventional known manufacturing techniques.
Still further, it is desirable to provide a mattress assembly that
is cost-effective to produce.
SUMMARY OF THE INVENTION
[0008] The present invention improves over the prior art by
providing a bed construction with a one-sided mattress assembly
supported on a rigid foundation. The one-sided mattress assembly
includes a core of wire springs including, but not limited to,
pocketed or open coil springs. The spring core of the mattress is
covered by a layer of resiliently compressible material covering
the upper sleeping surface thereof. The spring core of the mattress
is supported on a bottom layer constructed of a substantially rigid
material that is not generally compressible. The core of coil
springs is attached to the bottom layer around its periphery. The
rigid bottom layer of the mattress assures firm support for the
coil springs and thereby reduces sagging that may result from the
springs being poorly supported by the compressible padding under
the springs of a conventional two-sided mattress.
[0009] In connection with the present invention, the padding for
the top layer is selected to resist permanent compaction or
deflection. Moreover, padding is only needed on the top layer of
the mattress thereby reducing by one-half the amount of padding
required. Consequently, the mattress construction of the present
invention with a padded top layer and a rigid bottom layer
necessarily reduces the amount of material that is subject to
permanent compaction and therefore reduces the amount of permanent
deflection of the mattress overall. Maintenance of the mattress of
the present invention by rotating or turning the mattress over is
also avoided.
[0010] In order to further reduce sagging of the sleeping surface
of the mattress, a rigid foundation is provided to give further
support to the rigid bottom layer of the one-sided mattress and
therefore the spring core.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing and other novel features and advantages of the
invention will be better understood upon a reading of the following
detailed description taken in conjunction with the accompanying
drawings wherein.
[0012] FIG. 1 is an exploded cross-section view of a conventional
two-sided inner spring mattress;
[0013] FIG. 2 is an exploded cross-sectional view of a one-sided
inner spring mattress constructed according to the principles of
the invention;
[0014] FIG. 3 is a schematic plan view of a complete assembly of
Marshall coils for use in the mattress construction according to
the present invention illustrated in FIG. 2;
[0015] FIG. 4 is a partial perspective view, partly broken away, of
the Marshall coil assembly illustrated in FIG. 3; and
[0016] FIG. 5 is a partially exploded elevation view of a
foundation used in connection with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] Referring now to the drawings, and initially to FIG. 1, a
conventional two-sided mattress is illustrated in exploded
cross-section and designated generally by the reference numeral 10.
The conventional mattress 10 includes as a principal component a
wire spring assembly 12 of Marshall spring coils, as will be
described in detail hereinafter and which comprises the central
core of the mattress 10. The mattress 10 could also incorporate an
assembly of open coil springs or other wire inner springs. The
mattress 10 has an upper sleep surface 14 and a lower sleep surface
16, and therefore, is of a conventional type intended to be turned
over periodically to help minimize compaction of its padding
material and the resulting sagging of the mattress 10. Padding
material 18, which is identical on both sides 14 and 16 includes a
layer of closed-cell foam such as polyurethane. Covering the
material 18, on both sides of the mattress, is a ticking layer 20
which may be quilted and which may include additional foam in a
manner well-known in the art. The ticking layers 20 are fastened
such as by sewing to a border 22 which extends around the entire
periphery of the core 12 of coil springs.
[0018] Turning now to FIG. 2, a mattress 30 constructed according
to the invention is shown in exploded cross-section. The mattress
30, like the conventional mattress 10 illustrated in FIG. 1, has a
central core 12 of the Marshall coils. The mattress 30, however,
may have a central core 12 comprising open coil springs or other
wire springs. An upper sleep surface 34 is formed over the central
core 12 by a layer of foam padding 18 and a layer of ticking 20. In
accordance with the invention, however, the mattress 30 has an
underside 36, positioned under the central core 12 and which
comprises a substantially rigid layer 38 of material covered by a
thin layer 40 of a non-woven sheeting. A border 42 connects the
ticking 20 and sheeting layer 40 and extends around the periphery
of the coil spring assembly 12. A lower border wire 44 is secured
to the coil spring assembly 12 around its periphery as well as to
the layer 38 such as by hog rings 46.
[0019] FIGS. 3 and 4 illustrate one form of mattress core 12 of the
aforementioned Marshall coil construction. In this construction,
closely positioned coil springs are aligned in a string assembly 50
(FIG. 4) wherein individual springs 52 are each encapsulated within
a pocket of 54 of fabric material 56 which may be sewn or
ultrasonically welded to create the pockets 54 and to create a
unitary Marshall coil type assembly 12. An example of such
construction is more fully disclosed in U.S. Pat. No. 5,621,935
which is commonly assigned herewith and the disclosure of which is
incorporated herein by reference in its entirety. A person of
ordinary skill in the art will appreciate that opened coil springs
or other wire springs may be used for the mattress core 12 as well
as Marshall coil springs.
[0020] As previously described, the sleeping surface 34 comprises a
layer of foam padding 18 and a layer of ticking 20. The ticking 20
is of conventional construction. In accordance with the present
invention, however, the foam padding 18 is specifically selected to
provide comfort yet minimize compaction. Particularly, the foam
padding 18 is a high density polyurethane foam having a density
from about 1.0 lbs./cu. ft to 2.5 lbs./cu. ft. The foam layer 38
also has a firmness in a range of between 10 and 55 ILD, where
"ILD" refers to the standard Indented Load Deflection test. Within
the ranges specified, the foam padding 18 for the sleeping surface
34 is selected to provide varying degrees of firmness or softness
to accommodate individual preferences.
[0021] The relatively rigid bottom layer 38 is a high density
polyurethane foam having a density of approximately 1.85 lbs./cu.
ft. The foam layer 38 also has a firmness above 30 ILD. In
practice, an ILD above 55 has proven to be most effective based on
considerations of cost and durability. Other rigid materials may be
used in place of the foam layer 38. Such materials may include
solid plastic, wood, or other nonyielding rigid materials. To the
extent such materials for the layer 38 yield to pressure, such
materials must have at least a high degree of recoverability once
the pressure has been removed so that the materials are not
compacted.
[0022] Turning to FIG. 5, there is shown a foundation 60 for use in
connection with the construction of a bed in accordance with the
present invention. The most important aspect of the foundation 60
for the present invention is providing a rigid top surface 62 to
support the mattress 30 (FIG. 2). Rigid support of the mattress 30
by the foundation 60 further reduces the amount of sagging of the
sleeping surface 34. In order to achieve rigid support of the
mattress 30, the foundation 60 is constructed in accordance with
the disclosure of commonly assigned U.S. Pat. No. 5,940,908, and
particularly FIG. 6 of that patent.
[0023] The foundation 60 has a structural frame 64. The structural
frame 64 has a rectangular border including a pair of side rails
(only rail 66 is shown in FIG. 5). The side rails may be formed
from standard lumber of construction grade in nominal 1.times.3
size, connected at a head end of the frame 64 by a head end rail 68
and at the foot end of the frame 64 by a foot end rail 70. The end
rails 68 and 70 may be formed, for example, from a lower 1.times.2
end filler slat which butts the side rails in the plane thereof.
Cross slats 72, 74, 76, 78, 80, 82, and 84 are positioned on the
upper surfaces of the side rails and extend laterally to span the
transverse distance between the side rails. Optionally, a
longitudinally extending center support rail may be attached to an
undersurface of the head and foot rails 68 and 70 and secured to an
underside of each of the cross slats 72-84 to provide additional
structural integrity and strength for the frame 64.
[0024] As further illustrated in FIG. 5, it will be seen that cross
slats 80, 82, and 84 are centrally positioned along the length of
the frame 10 and have an L-shaped cross-section configuration.
However, it should be noted that the L-shaped cross slats may be
positioned elsewhere along the length of the frame 64 or be
employed in a lesser or a greater number. The L-shaped cross slats
80, 82, and 84 act as reinforcing braces or beams to reduce
deflection of the frame 64.
[0025] As illustrated in FIG. 5, the non-resilient bedding
foundation 60 has a mattress support assembly 86. The mattress
support assembly 86 comprises a plurality of wire support members
88 supported on and attached to the cross slats 68, 70, 72, 74, 76,
78, 80, 82, and 84. In this embodiment, a top layer 63 is applied
over the assembly 86 and a cover or ticking 90 is provided to form
the exterior surface for the entire foundation 60. The top layer 63
is similar in construction and performance to the bottom layer 68
of the mattress 30. Particularly, the top layer 63 is designed to
provide a rigid support surface for the mattress 30 with a firmness
above 30 ILD and specifically above 55 ILD.
[0026] The one-sided inner spring mattress 30 constructed according
to the invention offers considerable advantages over prior art
conventional two-sided mattresses in terms of reducing the amount
of permanent deflection of the sleeping surface due to undesirable
compaction of padding materials. Because the mattress 30
essentially has a 50 percent reduction in padding due to the rigid
bottom layer 38, the coil assembly 12 does not settle into and
compact a lower padding layer as would happen with a two-sided
mattress of conventional construction having identical padding
layers on both sides. The addition of a rigid foundation beneath
the one-sided mattress 30 also provides additional support for the
coil springs of the mattress 30 and thus helps further reduce
sagging.
[0027] The one-sided mattress 30 of the invention also offers the
advantage of eliminating maintenance of the mattress by
periodically turning it over as is recommended for conventional
two-sided mattresses. Accordingly, the one-sided mattress 30 is
more convenient for the consumer to use. Further, the Marshall coil
construction or open spring construction use conventional materials
so that the one-sided mattress 30 may be readily manufactured by
techniques that are well known in the industry. The foundation 60
likewise can be constructed using conventional manufacturing
techniques.
[0028] While the present invention has been described in connection
with certain embodiments thereof, it will be apparent to those
skilled in the art that many changes and modifications can be made
without departing from the true spirit and scope of the present
invention. Accordingly, it is intended by the appended claims to
cover all such changes and modifications as come within the scope
of the invention.
* * * * *