U.S. patent application number 10/877072 was filed with the patent office on 2005-02-10 for bed foundation.
Invention is credited to Hooper, William W. JR..
Application Number | 20050028275 10/877072 |
Document ID | / |
Family ID | 34139096 |
Filed Date | 2005-02-10 |
United States Patent
Application |
20050028275 |
Kind Code |
A1 |
Hooper, William W. JR. |
February 10, 2005 |
Bed foundation
Abstract
A bed foundation has a rectangular top panel and opposite side
and end panels depending downwardly from the top panel to form a
box-like enclosure having an open lower end, the panels being
formed integrally. A support structure of raised ribs in a
predetermined regular pattern is formed integrally on the lower
surface of the top panel. The foundation is made entirely or
substantially entirely from an expanded rigid plastic foam material
with high flame retardancy.
Inventors: |
Hooper, William W. JR.;
(Anderson, SC) |
Correspondence
Address: |
GORDON & REES LLP
101 WEST BROADWAY
SUITE 1600
SAN DIEGO
CA
92101
US
|
Family ID: |
34139096 |
Appl. No.: |
10/877072 |
Filed: |
June 24, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10877072 |
Jun 24, 2004 |
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10635973 |
Aug 7, 2003 |
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Current U.S.
Class: |
5/400 |
Current CPC
Class: |
A47C 23/05 20130101;
A47C 23/00 20130101; A47C 17/86 20130101; A47C 19/025 20130101 |
Class at
Publication: |
005/400 |
International
Class: |
A47C 019/00 |
Claims
I claim:
1. A bed foundation, comprising: a rectangular top panel having
opposite sides, opposite ends, and four corners, a pair of side
panels depending downwardly from opposite sides of the top panel,
and a pair of end panels depending downwardly from opposite ends of
the panel; the panels being formed integrally to form a unitary
box-like enclosure having an open lower end, and being of expanded
rigid plastic foam material; the top panel having an upper surface
and a lower surface; and a support structure formed integrally on
the lower surface of the top panel, the support structure
comprising raised ribs forming a predetermined regular pattern.
2. The foundation as claimed in claim 1, wherein the support
structure comprises first and second sets of parallel ribs which
intersect at an angle to one another to form a lattice.
3. The foundation as claimed in claim 1, wherein some of the ribs
are thicker than others.
4. The foundation as claimed in claim 2, wherein the lattice has a
rectangular pattern.
5. The foundation as claimed in claim 3, wherein the lattice has a
triangular pattern.
6. The foundation as claimed in claim 1, wherein the support
structure has a hexagonal pattern.
7. The foundation as claimed in claim 1, wherein the support
structure has an octagonal pattern.
8. The foundation as claimed in claim 1, wherein the foam is
selected from the group consisting of phenolic, urethane, and
poly-isocyanate rigid foam.
9. The foundation as claimed in claim 8, wherein the foam contains
at least one additive selected from the group consisting of
anti-oxidants, dyes, and mold release agents.
10. The foundation as claimed in claim 1, wherein the top panel has
a plurality of air holes extending over its entire area for
providing airflow to a mattress supported on the foundation.
11. The foundation as claimed in claim 10, wherein each air hole
has a diameter in the range from 0.5 inches to 4 inches.
12. The foundation as claimed in claim 1, wherein at least one of
the side and end panels has an opening, and a drawer is slidably
mounted in the opening for movement between open and closed
positions.
13. The foundation as claimed in claim 1, wherein the side and end
panels have outer surfaces which are textured to produce a
predetermined pattern.
14. The foundation as claimed in claim 13, wherein the pattern
simulates a quilted pattern.
15. The foundation as claimed in claim 1, wherein the top panel has
a textured, slip resistant upper surface.
16. The foundation as claimed in claim 1, further comprising a leg
adapter at each corner of the enclosure, each leg adapter having a
lower open end and a bore extending upwardly from the lower open
end for receiving the end of a support leg for supporting the
enclosure at a position raised above a floor surface.
17. The foundation as claimed in claim 16, wherein an additional
leg adapter is provided at the center of the enclosure.
18. The foundation as claimed in claim 16, wherein each leg adapter
comprises a hollow post of square cross-section extending from the
upper panel to the open lower end of the enclosure.
19. The foundation as claimed in claim 1, wherein the side panels
each have at least one opening.
20. The foundation as claimed in claim 19, wherein the openings are
rectangular.
21. The foundation as claimed in claim 20, including two drawer
units, each drawer unit being adapted for releasable slidable
engagement through the opening in a respective side panel.
22. The foundation as claimed in claim 19, wherein the openings are
circular.
23. The foundation as claimed in claim 19, wherein the openings
extend over at least 50% of the total surface area of the
respective panel.
24. The foundation as claimed in claim 1, wherein one end panel has
horizontal slots for mounting of a head board.
25. The foundation as claimed in claim 1, wherein the foam is of
the closed cell variety.
26. The foundation as claimed in claim 1, wherein the foam has a
density in the range from 5 to 20 pounds per cubic foot.
27. The foundation as claimed in claim 2, wherein the two sets of
ribs comprise a first set of spaced longitudinal ribs extending
between the opposite end panels and a second set of spaced
transverse ribs extending between the opposite side walls.
28. The foundation as claimed in claim 27, wherein at least the
transverse ribs are of varying height, the transverse ribs having a
height which increases from a minimum height at the end wall to a
maximum height at the center of the enclosure.
29. The foundation as claimed in claim 27, wherein each rib has
opposite ends at a junction with the respective opposite side or
end panels of the enclosure, each end having an extension extending
towards the open end of the enclosure for providing edge support to
the foundation.
30. The foundation as claimed in claim 1, wherein the foam material
is a composite material containing a filler material which is s
elected from the group consisting of particulate and fibrous
fillers for plastic composite materials.
31. The foundation as claimed in claim 30, wherein the filler
material is in the range from 1% by weight to 49% by weight.
32. A bed foundation, comprising: the top panel, and a pair of end
panels depending downwardly from opposite ends of the panel to form
a box-like enclosure having an open lower end, the panels being of
plastic material; at least one of the side or end panels having an
opening; and a drawer slidably mounted in the opening for movement
between an open position providing access to the drawer, and a
closed position flush with the respective panel.
33. The foundation as claimed in claim 32, wherein the box like
enclosure and drawer are formed of expanded rigid plastic foam
material.
34. The foundation as claimed in claim 33, wherein the top panel,
side and end panels each have an inner surface, and a lattice
support structure comprising first and second sets of intersecting
ribs is formed integrally on the inner surface of the support panel
and extends up to the inner surfaces of the side and end
panels.
35. The foundation as claimed in claim 32, wherein the top panel
has a plurality of air holes extending over its entire surface.
36. A bed foundation, comprising: a rectangular top panel having
opposite sides and opposite ends; a pair of side panels and a pair
of end panels depending downwardly from the sides and ends of the
top panel, respectively, to form a box-like enclosure having an
open lower end; the top panel, side panels, and end panels being
molded integrally in one piece from expanded rigid plastic foam
material; and the top panel having a plurality of openings.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part of application
Ser. No. 10/635,973 filed Aug. 7, 2003.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to bed structures, and is
particularly concerned with a bed foundation for supporting a
mattress or the like.
[0003] A conventional bed or mattress support typically consists of
a foundation unit or box spring unit placed on top of a metal bed
frame having side rails, cross members, and legs. A typical box
spring unit consists of a base having a wooden perimeter with
wooden cross slats which are nailed, glued, or stapled together,
metal spring units attached to the cross slats, and a suitable
cover. The separate metal base frame and foundation unit are
cumbersome and involve high labor costs in manufacture. Wood is
also highly flammable and current construction methods are
incapable of meeting new U.S. flammability standards.
[0004] Plastic bedding foundations to replace a conventional wood
and metal foundation have been proposed in the past. U.S. Pat. No.
5,953,775 of Mauro et al. describes a foundation which has a top
deck member, spaced side walls, and spaced end walls which may be
formed integrally or separately out of plastic material by
compression molding, injection molding, or thermo-forming. Patent
Application Publication No. 2002/0069462 of Gaboury et al.
describes a similar bed foundation made of blow-molded plastic. The
foundation is made up from separate components which can be secured
together to assemble the foundation. The multiple components may
make assembly of the foundation relatively complex.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a new
and improved bed foundation.
[0006] According to one aspect of the present invention, a bed
foundation is provided, which comprises a rectangular top panel
having opposite sides, opposite ends, and four corners, a pair of
side panels depending downwardly from opposite sides of the top
panel, and a pair of end panels depending downwardly from opposite
ends of the panel to form a box-like enclosure having an open lower
end, the panels being formed integrally and being of expanded rigid
plastic foam material, the top panel having an upper surface and a
lower surface, and a support structure formed integrally on the
lower surface of the top panel, the support structure comprising
raised ribs forming a predetermined regular pattern.
[0007] The support structure may comprise first and second sets of
parallel ribs which intersect at an angle to one another to form a
lattice. The lattice may be of square, rectangular, diamond pattern
or other geometric pattern. The lattice support structure may be
modified in order to provide the desired level of support for the
mattress. The central ribs may be made thicker or taller to provide
additional stiffness. The ribs may also be made thicker at the
edges of the top panel to fulfill the desired edge support
requirements. The support structure rib pattern may alternatively
be octagonal, hexagonal, or the like.
[0008] Expanded rigid plastic foam has not been used in the bed
foundation industry up to now, and is extremely strong while being
relatively light in weight. In an exemplary embodiment of the
invention, the foam was selected from the group consisting of
phenolic, urethane, and poly-isocyanate rigid foam for its flame
retardant properties and physical strength. The material may
include other additives such as anti-oxidants, dyes for different
color effects, particulate or fibrous fillers for added strength,
and mold release agents. A bed foundation unit of this material
will be rigid, strong, and light in weight, as well as exhibiting
high flame retardant properties which will meet current U.S.
federal standards. Another advantage in using expanded rigid
plastic foam material for the uni-body foundation is that the
material develops a dense, protective skin when molded. This skin
has inherent flame resistance and strength that allow for massive
cost reductions over conventional plastics when giving equivalent
or improved performance.
[0009] The box-like enclosure is integrally molded in one piece,
for example by reaction injection molding, to form a uni-body
foundation. In an exemplary embodiment of the invention, the top
panel has a plurality of small air holes extending over its entire
area to accommodate airflow through the mattress. These air holes
are useful in maintaining freshness of mattress sets within
enclosed spaces, by allowing air flow through the units and
discouraging development of mold and mildew.
[0010] The side and end panels may have openings, recesses or
cut-outs of predetermined shape to reduce the amount of material
required to manufacture the foundation and reduce overall weight,
while still providing a sufficiently strong load-bearing structure.
The openings may be of shapes such as elliptical, triangular,
square or other shapes which have load-bearing properties, and
there may be a single large opening in each panel or several
spaced, smaller openings and cavities. Horizontal slots may be
provided in one end panel for mounting of a conventional head
board.
[0011] In an exemplary embodiment of the invention, one or more
slide-out drawers may be mounted in a suitable opening in one or
more of the side and lower end panels, to provide storage space for
bedclothes or the like. Additionally, the outer surfaces of the
side and end panels may be textured in order to simulate a quilted
cover of the type often found on conventional bed foundation units.
A textured surface finish may also be provided on the upper surface
of the top panel. This provides a non-skid surface to resist
slipping of the mattress from its proper position centered on the
foundation.
[0012] This arrangement therefore provides a single, open box shape
foundation which can replace a previous bed frame and foundation or
box spring combination, when plastic legs are inserted in the
corner openings. Additional triangular supports with leg openings
may be provided in the center of one or more cross slats, if
provided, and may be desirable for larger size mattress
foundations. The foundation is much simpler, lighter in weight, and
less expensive than conventional bed foundations, and will have
improved flame retardant properties.
[0013] According to another aspect of the present invention, a bed
foundation is provided, which comprises a rectangular top panel
having opposite sides, opposite ends, and four corners, a pair of
side panels depending downwardly from opposite sides of the top
panel, and a pair of end panels depending downwardly from opposite
ends of the panel to form a box-like enclosure having an open lower
end, the panels being of plastic material, at least one of the side
or end panels having a rectangular opening, and a drawer slidably
mounted in the opening for movement between an open position
providing access to the drawer, and a closed position flush with
the respective panel.
[0014] The foundation is of predetermined dimensions based on the
size of the mattress to be supported, and will be provided in
different sizes to accommodate single, double, queen, king or other
standard bed dimensions. The side and end panels will also be
provided in different, standard heights, such as eight inch and
nine inch.
[0015] The bed foundation of this invention is made substantially
or entirely of expanded rigid plastic foam material, which is
exceptionally strong yet ultra light in weight. This material also
develops a dense skin when molded, which has inherent flame
resistance, unlike a conventional bed foundation which includes
wood components. The foundation exceeds all proposed and current
U.S. flammability standards for beds. The uni-body version requires
no assembly tools and can be readily installed. All of the
alternative versions are very inexpensive to produce and are of
relatively simple construction, and can completely eliminate
current metal bed frames and separate box springs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The present invention will be better understood from the
following detailed description of some exemplary embodiments of the
invention, taken in conjunction with the accompanying drawings in
which like reference numerals refer to like parts and in which:
[0017] FIG. 1 is a perspective view, partially cut away, of an
exemplary form of the bed foundation of this invention;
[0018] FIG. 2 is an enlarged sectional view taken on line 2-2 of
FIG. 1;
[0019] FIG. 3 is an end view of the bed foundation showing an
alternative arrangement of the lightening cut outs;
[0020] FIG. 4 is a side view of the bed foundation with support
legs and a mattress or box spring added;
[0021] FIG. 5 is a top plan view, partially cut away, of an
alternative knock down configuration of the bed foundation;
[0022] FIG. 6 is an enlarged view of one corner of the structure of
FIG. 5;
[0023] FIG. 7 is an enlarged sectional view taken on line 7-7 of
FIG. 5;
[0024] FIG. 8 is an end view similar to FIG. 3, but showing means
for attachment of the headboard;
[0025] FIG. 9 is a sectional view taken on line 9-9 of FIG. 8, with
a headboard secured in place;
[0026] FIG. 10 is a top plan view of a box spring base unit
according to another embodiment of the invention.
[0027] FIG. 11 is an enlarged sectional view taken on line 11 of
FIG. 10, with box springs and a cover indicated in broken line;
[0028] FIG. 12 is a side view of one end of the base of FIG. 10
with a headboard attached;
[0029] FIG. 13 is a bottom perspective view of a bed foundation
according to another embodiment of the invention;
[0030] FIG. 14 is a top perspective view of one of the drawers for
sliding engagement in a side opening in the foundation of FIG.
13;
[0031] FIG. 15 is a top perspective view of the foundation of FIG.
13, with the drawers in place;
[0032] FIG. 16 is a cross sectional view on the lines 16-16 of FIG.
14;
[0033] FIG. 17 is a cross sectional view on the lines 17-17 of FIG.
13, with a drawer in place in the drawer support;
[0034] FIG. 18 is perspective view of a leg for engaging in a leg
mounting bore in the foundation.
[0035] FIG. 19 is a perspective view similar to FIG. 14
illustrating the foundation supported on legs mounted in the
respective mounting bores.
[0036] FIG. 20 is a bottom perspective view of a bed foundation
according to another embodiment of the invention; and
[0037] FIG. 21 is a top perspective view of the foundation of FIG.
20.
DETAILED DESCRIPTION OF THE DRAWINGS
[0038] FIGS. 1 to 4 of the drawings illustrate a uni-body bed
foundation unit 10 according to a first embodiment of the present
invention, for supporting box spring and mattress, or a mattress 12
placed directly on top of unit 10 as indicated in FIG. 4. It will
be understood that the unit will be made in a range of lengths and
widths corresponding to the various standard mattress sizes, such
as single or twin, full, queen, king, California king, and in both
standard lengths and extra long lengths.
[0039] The unit 10 of FIGS. 1 and 2 is molded in one piece from an
expanded rigid plastic foam material. This material is cold-poured
into a suitably shaped mechanical mold. Expanded rigid plastic foam
materials are extremely lightweight yet durable, strong, and flame
retardant. In an exemplary embodiment the material was selected
from the group consisting of phenolic, urethane and poly-isocyanate
rigid foam of the closed cell variety, for flame retardancy, and
may be of a rating (cell density) of 90% or more.
[0040] Unit 10 has a rectangular upper panel 14 which has a
continuous, flat upper surface 15 for supporting a mattress 12 as
in FIG. 4, or a conventional box spring with a mattress placed on
top, if desired. Integral side walls 16 and end walls 18 depend
downwardly from the opposite side edges and end edges of panel 14.
This forms a box-like structure with a lower end opening. One or
more integral cross slats 20 may extend between the opposite side
walls 16 if required for additional strength. The unit also has
integral, triangular corner blocks or bosses 22 at the four corners
of the box-like structure. A mounting bore 24 extends upwardly from
the lower face of each corner block 22, for receiving the end of a
support leg 25 of the same material as unit 10. Support legs 25 are
a press fit in the respective mounting bores.
[0041] For larger size mattresses, and thus larger size foundation
units 10, one or more additional support legs may be provided along
the sides and at the center of the or each cross slat 20, for
example. In this case, triangular supports with leg mounting bores
will be formed integrally at the center of a cross slat and/or at
the junctions between cross slats and side walls. As noted above, a
mattress may be placed directly on top of foundation unit 10, as
indicated in FIG. 4, so that the unit replaces both a conventional
metal bed frame and a conventional wood and metal box spring
normally placed on a metal bed frame to provide a flexible support
for the mattress. In this case, a non-flexible support surface for
the mattress is provided. However, a flexible surface laminate 27
of the same material as unit 10 but lower density may be provided
on top of the less flexible panel 14, as indicated in dotted
outline in FIG. 2, to provide a support surface with a flexible
yield, simulating a box spring structure. This provides a dual
durometer layer construction for panel 14, comprising a lower layer
of higher rigidity and an upper layer of higher flexibility. The
two layers may be of substantially equal thickness or of different
thicknesses.
[0042] Each side wall 16, end wall 18, and cross slat 20 (if
present) has one or more openings or cut outs. In the embodiment
illustrated in FIGS. 1 and 2, each side wall has two rectangular
openings 26 and each end wall and cross slat has one rectangular
opening 28 extending across the majority of its length. These
openings have the purpose of reducing the amount of material
required, and thus the overall weight and cost of the foundation
unit, while not significantly reducing strength. Although the
openings are relatively large, rectangular openings in this
embodiment, they may be of other shapes and dimensions, such as a
plurality of circular openings 30 as illustrated in FIG. 3, or of
elliptical, square, polygonal, triangular, irregular or other
shapes, or combinations of different shape openings. The overall
effect is removal of 50% or more of the total material required for
making a solid wall of corresponding dimensions having no
openings.
[0043] As discussed above, foundation unit 10 may be manufactured
by cold-pouring the selected expanded rigid plastic foam material
into a mold with corresponding side wall openings and surface
structure. This technique generates no scrap or trimming waste and
is extremely efficient. Uni-body molding therefore allows the use
of less material and produces an inherently strong, integral
box-like structure. However, shipping costs may be relatively high
due to the overall size of the units.
[0044] FIGS. 5 to 7 illustrate an alternative, knock-down mattress
foundation unit or foundation assembly 35. This unit is of similar
structure to the one-piece or uni-body unit 10, but is made in
several separate generally flat parts which can be secured together
by suitable fasteners such as screws 36. The parts comprise at
least a flat upper panel 38, a pair of side walls 40, a pair of end
walls 42, and four corner blocks or bosses 44 forming both the
corner and the leg mounting boss at each corner of the unit 35. For
larger size mattresses, the knock-down unit also comprises one or
more cross slats 46, and optionally one or more separate,
triangular leg mounting units or bosses 48. The side walls, end
walls, and cross slat (if present) will all have openings or
cut-outs of any desired shape or combination of shapes, such as
rectangular cut-outs 26,28 as illustrated in the first embodiment.
This will reduce the overall weight of the assembly.
[0045] Each part of the foundation assembly 35 is made of the same
expanded rigid plastic foam material as the uni-body foundation
unit 10 of the previous embodiment. However, since each part other
than the corner pieces or leg mounting bosses is a flat panel, no
mold is required and the parts may be simply cut from a bun to the
appropriate dimensions. The material should be of a higher density,
suitably not less than 12 pounds per cubic foot, to enable
fastening of the parts with screws 36 and/or adhesives. The
thickness of the side and end panels will also be greater in this
embodiment than the uni-body version, to provide an adequate anchor
for the fasteners. The corner pieces will be molded in a suitable
mechanical mold of corresponding shape and dimensions.
[0046] As best illustrated in FIG. 6, each corner block 44 is
generally triangular in shape, with a rounded outer corner 50, a
flat, slanted inner face 52, and cut-outs or recesses 54 on each
side for receiving the end of the respective end wall 42 and side
wall 40. A leg mounting bore 55 extends upwardly from the lower
face of each block 44 for receiving legs 25 in exactly the same
manner as illustrated in the first embodiment. When the walls 40,42
are properly engaged in the respective recesses 54, they are
secured in position with fastener screws 36 as indicated. These may
be Phillips head tec screws or equivalent fasteners. Alternatively,
or additionally, spray adhesives may be used to secure the parts
together. The upper panel 38 is also secured to the side walls by
similar fasteners (not illustrated). The central leg mounting block
48 is a simple triangular block which also has a leg mounting bore
55 and is secured to the cross slat 46 by a screw and/or
adhesive.
[0047] The advantage of the knock down assembly over the uni-body
foundation unit 10 of the first embodiment is that shipping costs
will be lower, since the parts can be shipped prior to assembly in
a relatively small box, and then assembled on site quickly and
easily using only basic hand tools. Once assembled, the joint lines
in the knock down assembly will be nearly invisible, due to the
compression fit between the parts. The uni-body construction has
the advantage of requiring no assembly on site, but will require
larger storage space prior to installation and will be more
expensive to ship. In both cases, the product is made entirely or
almost entirely of expanded rigid plastic foam material (apart from
the fastener screws in the case of the knock down version). This
material is extremely strong, offering in excess of five times the
strength of comparable wood products, is nearly inflammable, and is
very light in weight. The foundation is very inexpensive to
produce, and completely eliminates the current unattractive and
heavy metal bed frame or bed frame and box spring combination,
replacing these parts with a single support unit and legs.
[0048] The side and end walls or panels in each of the above
embodiments will have at thickness in the range of 0.25 to 2.00
inches, with the side and end walls being thicker in the knock down
version to anchor the fasteners. The top panel thickness will be in
the range of 0.125 to 2.00 inches, again being thicker in the knock
down version. As noted above, the density will also be higher in
the knock down version, for the same reason. The height of the side
and end walls is at least 1 inch, and may be higher than this if
desired, based on the desired overall bed height. The length and
width of the top panel will be variable depending on the width and
length of the mattress to be supported.
[0049] FIGS. 8 and 9 illustrate an optional modification of one end
wall 18 or 42 of the foundation unit to allow mounting of a
headboard 56. End wall 18 or 42 is provided with two spaced pairs
of parallel, horizontal slots 58. The lower end of a headboard 56
is secured to the end wall of the foundation unit via nut and bolt
fasteners 59 extending through the slots and aligned openings in
the headboard, as illustrated in FIG. 9.
[0050] In both of the above embodiments, the foundation unit has
the general shape of a rectangular box, open at the bottom, with
all four corners radiused to the industry standard. On larger
units, typically queen size or larger, one or more transverse cross
braces may be used, depending on the sleep surface load
requirements. If necessary, longitudinal braces may be installed
between the end walls for additional strength. The corner units or
bosses have mounting bores for the plastic support legs 25, thus
eliminating the need for a separate bed frame and further reducing
cost and weight.
[0051] FIGS. 10 to 12 illustrate a box spring base unit or panel 60
according to another embodiment of the invention, for replacing a
conventional wood slat box spring base as well as the metal frame
which would normally support a conventional box spring unit. Unit
60 basically comprises a flat, rectangular panel with radiused
corners 62. The lower surface 64 of the panel may have rectangular
recesses 65 extending across a major portion of its width, as
indicated in FIGS. 10 and 11, to reduce overall weight. This also
produces a shape similar to that of a conventional wood slat box
spring, with the strips or portions 66 of material between the
recesses corresponding in position to the conventional wood slat.
The recesses may be replaced with openings extending through the
entire thickness of the panel, if desired. However, a solid panel
will exhibit better flame retardancy.
[0052] The panel or unit 60 will be made of the same expanded rigid
plastic foam material as the foundation units of the previous
embodiments, and may be made by cutting a bun slice of the foam
material of the appropriate thickness, or by molding. The foam
material selected may have a density of the order of fifteen pounds
per cubic foot. Downwardly facing leg mounting bores 68 are
provided at each corner for receiving the end of plastic support
legs 25, avoiding the need for a separate metal bed frame.
[0053] In order to complete the box spring unit, metal box springs
70 are tacked onto the upper surface 72 of the panel, as
illustrated in FIG. 11, and a suitable cover 74 is placed over the
box springs. The springs may be attached only around the periphery
of the recesses and along the strips 66 between adjacent recesses,
if desired. A mattress may then be placed on top of cover 74. A
solid panel with no openings has the advantage of higher flame
retardancy, since it will prevent flames from beneath the bed from
penetrating to the burnable materials typically used to enclose the
box springs.
[0054] FIG. 12 illustrates a headboard mounting bracket 75 for use
with the box spring flat or unit 60. Bracket 75 has a channel or
groove 76 for engaging over an end of the panel or unit 60. Bracket
75 is secured to the panel 60 via bolts 77, and has an upright
mounting flange 80 for attachment to the lower end of the headboard
56 via bolts 82 which extend through a slot in flange 80. The
bracket 75 may be made of the same lightweight and flame retardant
foam material as the box spring flat 60.
[0055] The panel 60 may have a thickness of the order of 0.125 to
2.00 inches to provide adequate supporting strength for the box
spring and mattress. The cross brace width, or width of portions 66
between adjacent recesses or openings, should be at least six
inches to provide an adequate base for the attached row of
springs.
[0056] FIGS. 13 to 19 illustrate a bed foundation 100 according to
another embodiment of the invention. The foundation is molded in
one piece from an expanded rigid plastic foam material, apart from
the drawers 102 and drawer support structures 118, 119 which are
molded separately. In one exemplary embodiment, the foam material
was a polyurethane rigid foam comprising a polyol, an isocyanate,
and optional additives such as anti-oxidants and mold release
agents. The foundation may be fabricated in one piece by reaction
injection molding, producing a unitary foundation with no seams or
joints.
[0057] The expanded rigid plastic foam material used to mold the
foundation has the property that a dense skin 101 is formed when it
is molded. This outer skin has inherent flame resistance and
strength when compared to conventional plastics materials. The
production of a protective, flame retardant skin on a bed
foundation is extremely advantageous in meeting flammability
standards. The foam material may include particulate or fibrous
fillers added to the resin, creating a composite material. Any
basic plastic composite fillers may be used, including silica and
boric oxide. Layers of fiberglass matting may be incorporated in
the foundation walls in lieu of, or in combination with, the
fillers as a structural enhancement. The matting may simply be laid
in the mold prior to blowing in the polyurethane foam material
around and over it. The use of fillers will enhance the structural
strength of the foundation unit while decreasing material costs,
since less polyurethane will be needed. The range of fiber material
in the mixture may be from 1% to 49% by eight, depending on
formulation and filler type.
[0058] The foundation is illustrated in FIGS. 13 to 19 with
optional slide-in drawer support structures 118, 119 for supporting
drawers 102, as well as leg adapters 104. However, one or both of
these options may be eliminated in alternative embodiments where
the foundation is to be mounted on a conventional bed frame and/or
where no drawers are required.
[0059] The foundation 100, as in the first embodiment above, is of
generally rectangular box-like shape, having a flat upper panel or
support 105 on which a mattress will be supported in use, and
integral, downwardly depending side walls 106 and top and bottom
end walls 108, 109. However, unlike the first embodiment, the
foundation of this embodiment has an integrally formed, lattice
support structure comprising perpendicular sets of intersecting
longitudinal and transverse ribs 110, 112 on the inner or lower
surface of the upper panel 105. Additionally, a plurality of air
holes or openings 114 are provided in the upper panel, as best
illustrated in FIGS. 13 and 15.
[0060] In the illustrated embodiment, one air hole is provided at
the center of each rectangular cell 115 formed by the intersecting
sets of ribs 110, 112, although a lesser number will be provided in
alternative embodiments. The number and size of the air holes 114
selected will be dependent on various factors. The purpose of the
air holes is to provide air flow to the mattress and maintain
freshness of the mattress, reducing the risk of mold or mildew
forming in a potentially damp environment. A secondary purpose is
to reduce the overall weight of the foundation. Typically, the air
holes will be larger where more air flow is required, for example
in smaller rooms or more enclosed environments.
[0061] A series of five leg adapters 104 are also molded into the
interior of the foundation, one at each corner of the foundation
and one at the center of the foundation, as best illustrated in
FIG. 13. Each leg adapter 104 comprises a hollow post of generally
square cross section. Legs 116 are provided for press fitting into
the respective adapter bores if the foundation is to be used
without a conventional metal bed frame, as illustrated in FIGS. 19
and 20. However, the leg adapters 104 may be eliminated if this
option is not desired. As best illustrated in FIG. 19, each leg 116
has a tapering portion 117 of square cross section which is a
frictional or interference fit into a respective bore 104, and a
shaped lower end portion 119 which acts as the support to hold the
foundation above the floor, as illustrated in FIG. 19.
[0062] The embodiment of the foundation illustrated in FIGS. 13 to
19 has two slide-in drawer units 102, one in each side wall 106. A
rectangular drawer support structure comprising a pair of side
walls 118 and an end wall 120 is secured in each side of the
foundation in alignment with a respective drawer opening 124. Each
side wall 118 of the drawer support has a slide groove 122 as best
illustrated in FIG. 17. Each drawer unit 102 has a slide rib 125 on
each side for sliding engagement in the respective groove 122 and
an outer face 126 which fits into opening 124 when the drawer is
closed, as illustrated in FIG. 15.
[0063] In the embodiment of FIGS. 13 to 19, the outer side and end
faces of the foundation, and the outer faces 126 of each drawer, if
provided, have a textured pattern 128 of wavy lines, as best
illustrated in FIGS. 13, 15 and 17. The textured pattern may be
formed in the mold. Where the foundation has drawers, the textured
pattern on the outer faces 126 is designed as a smooth continuation
of the pattern on adjacent regions of the side walls, as seen in
FIG. 15. This may be done by initially forming the side walls with
textured pattern, then cutting out a portion of each side wall to
form drawer opening 124, and using the cut out portion as the outer
face 126 of the drawer unit.
[0064] The textured pattern is provided on the outer surfaces of
the foundation which will be visible when the foundation is in use,
and is designed to simulate the quilting pattern of a more
conventional foundation with a traditional fabric cover. The
textured surface of the side and end walls may be of any desired
quilting pattern, such as lockstitch, chain stitch and "tack and
jump" patterns as known in the field, or may be of other decorative
patterns if desired. The upper surface of the upper wall 105 of the
foundation may also be provided with a slightly roughened texture
by suitable roughening or sand blasting of the corresponding mold
surface. This will produce a non-skid surface, reducing the risk of
a mattress slipping to one side in use.
[0065] The lattice support structure of longitudinal and transverse
ribs or stringers 110, 112 provides a support system for the upper
wall or horizontal platform 105, and also adjusts the level of
support provided for the mattress. The rib height and thickness can
be modified for increased or reduced support, as necessary. In the
illustrated embodiment, the longitudinal ribs 110 are of fixed
height while the transverse ribs 112 vary in height from the ends
to the center of the foundation, as illustrated in FIG. 13, with
the ribs 112 being taller at the center of the foundation where
more support is typically required. The ribs 110, 112 have tapered
extensions 130 at their ends extending towards the open bottom end
of the foundation, at the junction between the upper wall or panel
105 and the side and end walls, to provide the necessary edge
support, as best seen in FIG. 13. Although the ribs are
perpendicular in the illustrated embodiment and form a rectangular
lattice pattern, the lattice support structure may alternatively be
formed in a diamond, hexagonal, octagonal, or other regular
pattern.
[0066] Although the foundation unit in FIGS. 13 to 19 is provided
with two slide-out drawers in the side walls, additional drawers
may be provided if desired, as space permits, for example in the
end wall 109, and the drawers and drawer supports may be omitted
altogether in other alternative embodiments. The top end wall 108
of the foundation unit 100 may be modified to allow for mounting of
a headboard, in the same way as illustrated in FIGS. 8 and 9 for
the first embodiment. If desired, the side and bottom end walls may
also be provided with cut outs, as in the first embodiment, to
reduce material costs and overall weight of the unit.
[0067] FIGS. 20 and 21 illustrate a modified foundation unit 150
which is similar to the foundation unit of the previous embodiment,
but which is of simpler structure. As in the previous embodiment,
foundation unit 150 has an upper wall or panel 152 and downwardly
depending side walls 154 and end walls 155, as well as an
integrally formed lattice support structure on the lower surface of
the upper panel 152. The lattice support structure comprises two
sets of parallel, intersecting longitudinal and transverse ribs or
stringers 156, 158. As in the previous embodiment, the transverse
ribs 156 are of gradually increasing height from each end wall 155
up to the center of the foundation, where they have a maximum
height for added support and strength in this region.
[0068] The outer surfaces of the side and end walls in this
embodiment are smooth and have no textured pattern, unlike the
previous embodiment. The foundation of FIGS. 20 and 21 may be
provided with a conventional fabric foundation cover. The lower
edges of the side and end walls may be curved inwardly to provide a
convenient staple lip for attachment of the cover. There are also
no drawer openings or supports, or drawers, and no leg adapters,
although leg adapters 104 may optionally be provided in this
version. As in the previous embodiment, a series of air holes 160
are provided in the upper wall 152 for air flow to the mattress.
The air holes 160 are smaller in this case, and are of the order of
0.5 inches in diameter. This size of air hole will be used where
there will be plenty of space and ventilation in the room where the
foundation will be used. Again, airflow is provided through the
foundation to the mattress, thereby discouraging the formation of
mold and mildew. The air hole diameter will be increased for
foundations to be used in more enclosed spaces.
[0069] In each of the above embodiments, a conventional metal bed
frame and foundation or box unit or box spring is replaced by a
simple, lightweight unit or assembly of flame retardant, expanded
rigid plastic foam material. In the first two embodiments and the
last two embodiments, the foundation is of a box-like shape with an
open base, and the mattress is placed directly on top of the upper
panel of the unit. In the third embodiment, the foundation is a
flat panel for replacing a conventional box spring base or flat,
with corner openings for receiving plastic legs, and with box
springs stapled to the upper surface of the panel with a suitable
surrounding enclosure. The material chosen for the bed foundation
of this invention is a considerable improvement over conventional
bed frame and foundation construction materials, with much higher
flame retardancy, lighter weight, reduced complexity, yet
equivalent or better strength and durability. This invention
completely eliminates the need for a separate metal bed frame when
used with the leg adapters and optional plastic legs.
[0070] Molding of the foundation unit in rigid plastic foam
material such as a polyurethane rigid foam will inherently produce
an outer protective skin which has flame retardant properties,
unlike conventional plastic materials as previously used in bed
products. The air flow holes in the upper panel can be customized
for the environment in which the foundation will be used, and will
help to maintain the freshness of the mattress and reduce formation
of mold and mildew. The optional texturing of the side and end
walls of the unit can simulate the effect of a conventional fabric
foundation cover at reduced expense.
[0071] Although some exemplary embodiments of the invention have
been described above by way of example only, it will be understood
by those skilled in the field that modifications may be made to the
disclosed embodiments without departing from the scope of the
invention, which is defined by the appended claims.
* * * * *