Mattress which conforms to body profile

A mattress or pad that contours and conforms to the body profile of a reclining individual. The preferred embodiments contain flexible, airtight chambers, at least two of which are interconnected to allow the transfer of air or liquid. Interconnected chambers are positioned and dimensioned to conform to and support the natural curves of a reclining body. The volume of fluid, e.g., air or liquid, within all of the chambers can be easily adjusted to allow comfortable resistance and conformity to a wide range of body lengths, weights, and shapes. Preferred embodiments have insulative, self inflating elements, comprising low-density, open-celled, flexible foam in a rectangular configuration, in a thin-walled cylindrical configuration, and in an arced configuration determined by an adhered heat-reflective plastic film.

BACKGROUND 
1. Field of Invention 
This invention relates generally to mattresses, specifically to a mattress 
which conforms to the body shape of a user. The inventive mattress 
provides improved conformability to varied body sizes, weights, and 
positions. The preferred embodiments have insulative, self-inflating 
elements within the mattress. 
2. Discussion of Prior Art 
There are many types of mattresses which have been designed to give a 
reasonable degree of comfort to users. The "comfort" principle behind all 
mattresses is the same, however: the more the mattress conforms to the 
natural curves of the body which it supports, the more comfortable the 
mattress feels. 
Heretofore, mattresses have had four primary constructions. 
One of the oldest constructions is a fabric sack stuffed with a soft, 
yielding material of relatively low resilience, such as cotton or 
feathers. A principal disadvantage of this type of mattress is that the 
stuffing tends to pack, developing cavities and bumps, so that it needs to 
frequently be shaken, pummelled, and forced back into shape. 
Another, more recently developed type of construction comprises a 
relatively flat, flexible surface backed by a resilient yielding structure 
or medium which offers smoothly increasing resistance as the surface is 
deformed. Examples of this type are innerspring mattresses, flexible open 
celled foam mattresses, and various types of air mattresses. A 
disadvantage with these mattresses is that they cannot completely conform 
to body profiles, but instead have reduced support for the 
upwardly-concave areas, such as the lumbar (small-of-the-back) region, and 
overly firm support or pressure at the downwardly-convex regions, such as 
the buttocks and upper back. This necessitates offering innerspring 
mattresses, for instance, in soft, medium and firm grades to provide a 
partial compromise for the user. 
Still another type of construction comprises a mattress which is 
mechanically deformed by linkages, pneumatic, or hydraulic means, thereby 
to conform to a preferred body position. Examples of this type are 
"hospital" beds which elevate the upper body and the knees. These beds 
tend to be heavy, expensive, and only minimally comfortable to a user in 
any position other than supine. 
Yet another type of construction comprises various forms of water filled, 
water and foam filled, or liquid and floating body filled mattresses. 
These attempt to float the body on a very flexible surface backed by a 
liquid medium; this gives extremely uniform support, and has a resistance 
to deformation which increases very gradually. While the best of these 
mattresses can approach the ideal in comfortable, body profile conforming 
support, they have a number of disadvantages. They are heavy, require 
periodic maintenance, require an electrical heater, can spill if a 
puncture occurs, and tend to produce excessive wave motions which can be 
disturbing. 
The last type of construction comprises a mattress with depressions and 
slots for the abdomen, breast, and face of a prone sleeper. While the 
addition of removeable elements, or inflatable/deflatable sections, allows 
such a mattress to be used for positions other than the prone, it is 
inconvenient to adjust, and is no more conformable to body contours, in 
the supine or side positions, than are other flat, resilient mattresses. 
While the foregoing constructions can be utilized by the best designers to 
make mattresses having a degree of comfort, the resulting products, as 
stated, are usually heavy, bulky, intricate, expensive, difficult to 
fabricate, and/or easily damaged. Also, none of these mattresses offer 
adequate support of the head, with support for the neck and a comfortable 
hollow for the shoulder, when the user is lying on his or her side. Thus a 
separate pillow is required, but even this provides less-than-ideal 
support. 
OBJECTS 
Accordingly several objects of this invention are to offer a superior 
mattress for supporting the natural curves of a reclining body, to provide 
a mattress which self-adjusts to various body sizes, weights, and 
positions, to provide a mattress which supports the head while offering a 
comfortable hollow for the shoulder, and to accomplish this in a light, 
simple, and inexpensive construction. Further objects and advantages will 
become apparent from a consideration of the drawings and ensuing 
description thereof.

DESCRIPTION MATTRESS WITH SELF-INFLATING ELEMENTS--FIGS. 1-4 
The embodiment of the invention shown in FIGS. 1, 2, 3, and 4 comprises 
upper and lower sheets of heat-sealable, fluid-impermeable air tight 
fabric 10 and 12. These are sealed together to form interconnected raised 
(convex) hermetically - sealed compartments or chambers 20, 28, and 32, 
connected by passages 24, 25, 27, and 29. Chambers 22, 30, and 34 are 
isolated from the raised compartments. All chambers contain 
generally-rectangular blocks or pieces of low-density, open-celled, 
flexible urethane foam. Upper sheet 10 is cut away to show the foam at 40, 
42, 44, 46, 48, 50, 52, 54, 56, 58, 60, and 62. Four manually-operated air 
valves 14, 15, 17, and 19 are sealed to and penetrate the bottom fabric 11 
in four of the chambers, 20, 22, 30, and 34. (FIGS. 1 and 2). The valves 
consist of relatively small, flexible plastic units situated in upper 
outside corners of the chambers, where it is unlikely that a user's body 
will bear down on them. 
Head chamber 20 is 23 cm long by 10 cm thick by 58 cm wide, and has valve 
14 in an upper corner, on the underside of chamber 20. This chamber 
cushions the neck and head of a supine body (FIGS. 3 and 4). (All 
dimensions approximate.) 
Passages 24 and 25 are about 6 cm wide by 4 cm thick by 40 cm long, and 
enable air to flow from head chamber 20 to lumbar chamber 28, and 
vice-versa (FIG. 1). 
Back chamber 22 has a transverse dimension of 44 cm, a thickness of 4 cm, 
and a longitudinal dimension of 38 cm. Valve 15 is located in an upper 
corner, on the underside of chamber 22. Chamber 22 contains two pieces of 
foam 42 and 44, separated by a center seal 16. An opening 26 is provided 
around the end of this seal. This chamber supports the upper torso of a 
supine body (FIGS. 3 and 4). 
Lumbar chamber 28 is 20 cm long by 7.5 cm thick by 58 cm wide. The upper 
surface of this chamber is convex and supports the lumbar region with 
uniform pressure over substantially the entire area (FIG. 3). 
Passages 27 and 29 are 6 cm wide by 4 cm thick by 20 cm long, and enable 
air to flow from lumbar chamber 28 to thigh chamber 32, and vice versa 
(FIG. 1). 
Seat chamber 30 is 20 cm long by 7.5 cm thick by 44 cm wide, and has valve 
17 in an upper corner, on its underside. This chamber supports the 
buttocks (FIG. 3 and 4). 
Thigh chamber 32 is 20 cm long by 7.5 cm thick by 58 cm wide. This chamber 
is convex upward and supports the lower region of the buttocks and upper 
region of the thighs with uniform pressure over a substantial area thereof 
(FIG. 3). 
Leg chamber 34 is 78 cm long by 2.5 cm thick by 58 cm wide, and has valve 
19 in an upper corner, therebeneath. It contains two pieces of foam 60 and 
62, separated by a seal 35, with an opening 36 around the upper end of 
this seal. Seals 35 and 16 have enlarged, rounded terminations; these 
reduce local stresses, during pressurization, on the heat sealed fabrics. 
Chamber 34 supports the legs and feet (FIG. 3 and 4). 
Heat seal 13 runs around the entire perimeter of the mattress, and also 
separates thigh chamber 32 from leg chamber 34 (FIG. 1). 
The embodiment of FIGS. 1 to 4 is preferred as a portable mattress for 
camping or occasional use. It has the advantages of being light, 
self-inflatable, collapsible to small size, and adjustable to a wide range 
of body sizes. 
Cylindrical Self-inflating Element--FIGS. 5a, 6 
FIGS. 5a and 6 show an embodiment of an insulative self-inflating element, 
employing a thin flat sheet of low-density, open-celled, flexible urethane 
foam 64, adhered together on two edges to form a seam 66. This turns flat 
sheet 64 into a resilient, springy cylinder, which, when flattened, tends 
to return to its round shape. Such a cylindrical insulative self-inflating 
element may be used in chambers 20, 28, and 32 in lieu of foam blocks 40, 
50, and 58. These cylindrical elements are lighter and less expensive, if 
efficiently manufactured, than foam blocks. However the cylinders have 
slightly less insulative value than a solid block, and are more difficult 
to manufacture. 
Heat-reflecting Self-inflating Element--FIGS. 5b, 7 
FIGS. 5b and 7 show another insulative self-inflating element. The element 
is composed of a thin sheet of low-density, open-celled, flexible urethane 
foam 68 and an infrared radiation-reflecting bottom film 70, e. g., of 
aluminized polyethylene plastic. Film 70 is bonded to the edges of foam 
sheet 68 by adhesives such as foam bonding contact adhesive, and holds 
sheet 68 in an arc. Such an element may be used in all chambers of the 
embodiment shown in FIGS. 1 through 4. The advantages of this element over 
the cylindrical element of FIGS. 5 and 6 are lighter weight and less 
expense when manufactured efficiently. However it is more difficult to 
manufacture, and must be carefully positioned and adhered within the 
chambers of a mattress. 
Inflated and Non-inflated Chambers--FIG. 8 
FIG. 8 shows another embodiment of the invention. Two sheets of heat 
sealable, air-tight fabric are sealed together to form chambers and 
passages, as in the first-described embodiment (FIGS. 1-4). However, head 
chamber 20, lumbar chamber 28, thigh chamber 32, and passages 24, 25, 27, 
and 29 do not contain insulative, self-inflating elements, but instead are 
air-inflated through valve 14. Alternatively, these chambers and passages 
may have the insulative self-inflating elements of FIGS. 5, 6, or 7, or 
other insulative and/or self-inflating elements. For instance, an 
insulative, non-self-inflating filling, such as polyester wool, which has 
lower weight than open-celled flexible foam, may be used. Also, infrared 
radiation reflecting film may be adhered to the heat-sealable sheets 
comprising the body of the mattress. Back chamber 22 and seat chamber 30 
are not air tight, and contain 2.5 cm thick sheets of closed cell or very 
stiff open-celled foam blocks 86 and 90. Leg chamber 34 contains a 1.5 cm 
thick sheet of a softer open celled foam 94, which nonetheless has 
adequate support for the legs. Rather than valves, these chambers have 
simple grommeted openings 100, 104, and 106. 
The advantages of this embodiment over that of FIGS. 1-4 are that it has 
fewer inflated chambers and fewer inflation valves, and is therefore less 
expensive to manufacture. However the noninflated chambers cannot be 
adjusted to the specific preferences of each user. 
Mattress with Chambers Inside Foam Element--FIG. 9 
FIG. 9 shows a cross-sectional, side view of another preferred embodiment 
of the invention. A low-density, open-celled, flexible urethane foam 
self-inflating element 72 is covered by fabric or coating 70, and has 
embedded within it two sheets of heat-sealable, air-tight fabric 10 and 
12. These sheets are sealed together to form head chamber 20, passage 25, 
lumbar chamber 28, passage 27, and thigh chamber 32. Valve 83, in 
combination with self-inflating element 72, allows the chambers and 
passages to automatically fill with air or liquid. 
The advantages of this embodiment are that it has a greater range of 
adjustment than the other embodiments, is softer and thicker, and offers 
less resistance across the abdomen to a figure lying prone. The only 
disadvantages in respect to the other preferred embodiment of FIGS. 1-4 is 
that it is bulkier and more complex to manufacture. However, because of 
its greater comfort and simpler adjustability, it may be preferred as a 
conventional, or non-portable, mattress. 
Inflatable without Separated Chambers--FIG. 10 
FIG. 10 shows an inflatable mattress, without self-inflating or supportive 
foam elements, with "chambers," sections, or regions defined by straight 
bar seals, and with a single valve 14. Due to the spacing of the seals, 
the mattress has effective support regions comprising convex head region 
20, flat back region 22, convex lumbar region 28, flat seat region 30, 
convex thigh region 32, and flat leg region 34. The bar seals, and those 
in all following embodiments, have enlarged and rounded terminations, to 
reduce stresses at these points, during pressurization, on the fabrics 
which are heat sealed together. This embodiment has the advantage of being 
very light, simple, and inexpensive to manufacture. However, it is not 
self-inflating, has less effective thermal insulation and less 
adjustability than the embodiment of FIGS. 1-4, and tends to "bottom out," 
allowing the user's body to contact the ground when the mattress is not 
fully inflated. 
Inflatable Mattress with Separate Chambers--FIG. 11 
FIG. 11 shows another configuration of inflatable mattress, without 
self-inflating or supportive foam elements. This mattress has chambers and 
passages similar to the embodiment of FIGS. 1 through 4, with air valves 
14, 15, 17, and 19. Back chamber 22, seat chamber 30, and leg chamber 34 
have closely spaced seals which, under inflation, form connected tubular 
support surfaces similar to those of conventional, tubular, air 
mattresses. This embodiment has an advantage over that of FIG. 10 in 
adjustability due to the separate chambers, but similarly is not 
self-inflating, and has less thermal insulation than the embodiment of 
FIGS. 1-4. 
Mattress without Interconnecting Chambers--FIG. 12 
FIG. 12 shows yet another configuration of inflatable mattress, which may 
or may not have insulative and/or selfinflating elements. This mattress 
differs significantly from the above-detailed embodiments in that there 
are no interconnected chambers. This embodiment may be preferred if the 
mattress is to serve double duty as an emergency flotation device. In this 
use, the mattress would retain more buoyancy, in the event of one or more 
punctures, than the previously described embodiments. 
Non-inflatable with Separate Segments--FIG. 13 
FIG. 13 shows an embodiment of the invention which is not inflatable. 
Sections Segments of the mattress are interconnected by, and encased in, a 
fabric 155. Head segment 156 is relatively soft and yielding, back segment 
158 is relatively firm, lumbar segment 160 is soft and yielding, seat 
segment 162 is quite firm, thigh segment 164 is soft and yielding, and leg 
segment 166 is relatively firm. This embodiment may be preferred where 
only the supine position is assumed, and the reliability of a non-inflated 
mat or cushion is desired. The fabric 155 may be water-tight to allow use 
of the cushion as a buoyant float. 
Inflatable or Non-inflatable Mattress with Homogeneous Support 
element--FIG. 14 
FIG. 14 shows another embodiment of the invention which comprises a single 
piece of foam 170 or other resilient material, which is cut, molded, or 
otherwise shaped to provide the following respective regions: head region 
170, back region 174, lumbar region 176, seat region 178, thigh region 
180, and leg region 182. The inflatable embodiment comprises a shaped 
homogeneous core of low-density, open-celled, flexible urethane foam, with 
an air tight coating or fabric adhered to the entire surface. The 
noninflatable embodiment may or may not include a fabric cover or coating 
168. This embodiment may be preferred for a supine-only position, where a 
configuration which is simpler than that of FIG. 13 is desired. 
Operation--FIGS. 1-4 
The mattresses of this invention utilize conformable chambers which follow 
the natural curves of the body. Within the preferred embodiments, there 
are adjustable, interconnected chambers with self-inflating means. 
In the embodiment shown in FIGS. 1 through 4, three of these chambers--head 
chamber 20, lumbar chamber 28, and thigh chamber 32--are interconnected, 
and have convex upper surfaces under the neck and head, under the small of 
the back, and under the upper thighs, as shown in FIGS. 2, 3, and 4. 
Foam pieces 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, and 62 in each 
chamber serve as thermally-insulative, self-inflating elements. The foam 
pieces aid insulation by reducing the convective circulation of air from 
hot to cold, and by impeding the radiative heat losses. 
The mattress can be collapsed or reduced in volume for storage. This is 
accomplished by opening all valves and rolling the mattress into a tight 
cylinder, starting with the leg end. This collapses the contained foam 
pieces, driving the air out of them. The valves are then closed, and 
atmospheric pressure on fabric sheets 10 and 11 keeps the foam from 
re-expanding. When the mattress is to be used, the valves are opened, and 
the foam pieces will self-expand, drawing air into the chambers and 
passages, where it resides in the interstices of the foam. 
Head chamber 20, lumbar chamber 28, and thigh chamber 32 are approximately 
three times as thick or high as back chamber 22, seat chamber 30, and leg 
chamber 34. 
As shown in FIG. 1, the mattress is elongated; its length is over twice its 
width. As also shown in FIG. 1, chambers 20, 28, and 32 are each 
elongated, in a direction perpendicular to the direction of elongation of 
the mattress, so that their lengths are at least twice their widths, their 
widths being all about equal in dimension. As shown in FIG. 2, back 
chamber 22 provides a recess or concave area, between head chamber 20 and 
lumbar chamber 28, which is substantially longer (about twice as long), in 
the direction of elongation of the mattress, than the width of either head 
chamber 20 or lumbar chamber 28 so as to accommodate the upper back area 
of a user of predetermined size, as shown in FIG. 3. Seat chamber 27 
provides a recess or concave area, between lumbar chamber 28 and thigh 
chamber 32, which is about as long, in the direction of elongation of the 
mattress, than the width of either lumbar chamber 28 or thigh chamber 28 
so as to accommodate the buttocks of a user of predetermined size, as also 
shown in FIG. 3. Leg chamber 34 provides a recess or concave area, below 
thigh chamber 32, which is substantially longer (over three times as 
long), in the direction of elongation of the mattress, than the width of 
thigh chamber 28 so as to accommodate the legs of a user of predetermined 
size, as also shown in FIG. 3. As shown in FIGS. 2, 9, 13, and 14, the 
thickness of each portion of the mattress between its raised portions or 
chambers 20, 28, and 32 is less than the width of each of these raised 
portions. 
When a person using the mattress reclines on his or her back (FIG. 3), this 
height difference allows head chamber 20 to support the head and hold the 
neck supported in a natural curvature. Lumbar chamber 28 supports the 
concavity of the lower back in a natural curvature, and thigh chamber 32 
supports the thighs at a comfortable level above the buttocks. 
Air pressure in these chambers can be varied by filling or deflating them 
with valves 14, 15, 17, and 19, thereby to fit the contours of the user's 
body. The upwardly-convex chambers, comprising head chamber 20, lumbar 
chamber 28, and thigh chamber 32, together with the thinner and flatter, 
though nonetheless variable-height chambers 22, 30, and 34, effectively 
provide a "depth" equivalent to a much thicker standard or flat mattress. 
This feeling of depth is achieved by the upwardly-convex chambers 
conforming to and supporting the body's concave-up regions, coupled with 
the adjusting of air pressure in the chambers to achieve a sensation of 
equalized support or resistance for substantially the entire body. 
This sensation of equalized support is easily achieved as follows: 
Valves 14, 15, 17, and 19 are opened to allow the mattress to self-inflate. 
Back chamber 22, seat chamber 30, and leg chamber 34 self-inflate to a 
thickness which prevents an average range of users' bodies from "bottoming 
out," or contacting the ground or surface beneath the mattress. Similarly, 
head chamber 20, lumbar chamber 28, and thigh chamber 32 self-inflate to a 
height which offers support for the concave-up regions in an average range 
of user's body types. 
On first use, the user closes all valves after the mattress self-inflates, 
and lies down on it in a variety of positions to test conformity. He or 
she then adds or vents air until an optimum comfort is achieved. On 
subsequent deployments, the user will estimate an approximate addition or 
venting prior to closing each valve. In testing with users of various body 
types, the "comfort range" seems sufficiently broad to allow an easy 
estimation for re-use. 
The conformity and equalized support achieved by this configuration is a 
very significant factor for comfort. This can be especially appreciated 
when comparing a mattress of this design with a customary camper's 
mattress, which is thin and flat. 
Back chamber 22 and leg chamber 34 have test seals 17 and 35 down the 
centers, to reduce billowing and consequent loss of air pressure support 
when the user's body does not cover a substantial area of each chamber. 
Interconnection of the head chamber 30, lumbar chamber 28, and thigh 
chamber 32, by the passages 24, 25, 27, and 29, allows air to flow between 
the chambers. This offers several advantages: 
First, the interconnection allows pressure in the three chambers to 
equalize, resulting in equal support or resistance per unit of surface to 
three sensitive regions of the body, the neck and head, lower back, and 
thighs. This equalized support is a significant subjective comfort factor. 
Second, the interconnection allows adjustable support for these regions of 
the body by means of a single valve 14. By adding or venting air through 
valve 14, the user can adjust support pressure or resistance in chambers 
20, 28, and 32. 
Third, the interconnection allows the height or loft of head chamber 20 to 
change supportively as the user shifts from lying face up to lying on one 
side, as shown in FIG. 4. This is caused by the displacement of air from 
lumbar chamber 28 and thigh chamber 32 into head chamber 20. A further 
advantage of this increase in height of head chamber 20 when the user lies 
on his or her side is that, in effect, a "pocket" forms for the shoulder, 
giving a depth and resulting comfort that the we believe to be unique in 
mattress design. 
An additional advantage brought about by selective adjustment of air volume 
in the chambers of this mattress is the adjustability in length. It can be 
appreciated that the inflation of a chamber comprised of flexible 
air-tight fabric changes its cross section from flat to round. If 
inflatable mattresses have transverse inflatable chambers, as do the 
mattresses of FIGS. 1-4, and FIGS. 8, 9, 10, 11, and 12, the longitudinal 
dimension of these mattresses will decrease as air is added to one or more 
of the chambers. It can further be appreciated that selective adjustment 
of the unconnected chambers of the mattress in FIGS. 1-4 and the mattress 
in FIG. 12 can change the dimension of one section or chamber relative to 
the others. 
Operation--FIG. 6 
Thermally insulative elements are necessary in a thin mattress which is to 
be used outdoors or in unheated tents, vehicles, etc. Insulative 
self-inflating elements are provided in several embodiments of this 
invention for two reasons: they serve as thermal insulation to reduce heat 
loss from the body of a user to the ground or other cold surface, and they 
eliminate or reduce the effort required to inflate the mattress chambers. 
The insulative self-inflating element of FIG. 6 may be preferred to 
rectangular foam piece. An element of this configuration will have less 
total material than a solid foam piece for an equivalent volume of 
inflation in a chamber. We have found that a 2 cm.times.44 cm.times.58 cm 
sheet of low-density, opencelled, flexible urethane foam, when converted 
into a cylinder, expanded head chamber 20 to the same volume as a 10 
cm.times.23 cm.times.58 cm piece of solid foam. The cylindrical element of 
FIG. 6 was therefore approximately 2.5 times as effective, per unit of 
foam, as the solid foam. This element may be advantageously used in head 
chamber 30, lumbar chamber 28, and thigh chamber 32. Back chamber 22, seat 
chamber 30, and leg chamber 34 do not have sufficient thickness and 
resultant volume to make use of a cylindrical element advantageous over a 
solid sheet of foam. 
Operation--FIG. 7 
The insulative self-inflating element of FIG. 7 uses less equivalent foam 
per volume of inflation than the cylindrical element of FIG. 6. When 
tested, foam piece 68, with half the volume of foam piece 64 of FIG. 6, 
inflated head chamber 20 to approximately 2/3 the volume achieved by the 
cylindrical element. It was therefore 1.3 times as effective per unit of 
foam. This element also has an infrared radiation reflecting component, 
aluminized film 70, which causes it to have twice the insulative value of 
an equivalent thickness of foam. 
The element of FIG. 7 may be advantageously used in all chambers of the 
mattress of FIGS. 1-4. In head chamber 20, lumbar chamber 28, and thigh 
chamber 32, both inflative and insulative features are valuable. In back 
chamber 22, seat chamber 30, and leg chamber 34, the insulative feature of 
this element is valuable. 
Operation--FIG. 8 
The embodiment of FIG. 8 is similar to that of FIGS. 1-4, but is simplified 
by a reduction in the number of inflated chambers. Back chamber 22 and 
seat chamber 30 rely on very firm foams rather than air inflation to 
prevent the back and buttocks from "bottoming out." Leg chamber 34 may 
contain a softer foam, since the weight per unit area of the legs is 
normally less than that of the torso. None of these three chambers require 
an inflation valve, as they do not rely on inflation pressure. This 
embodiment does not have the range of adjustment of the embodiment of 
FIGS. 1-4, but is simpler and less expensive to manufacture. 
Operation --FIG. 9 
The embodiment shown in FIG. 9 utilizes the same principles as the mattress 
of FIGS. 1-4, although the arrangement of elements is considerably 
different. Insulative self-inflating element 72 surrounds and is bonded to 
the outside of chambers and passages formed by heat-sealing air-tight 
fabrics or films 10 and 12. While the self-inflating elements of the 
embodiment in FIGS. 1-4 are inside the chambers and passages, and function 
by expanding and being compressed, the mattress of FIG. 8 relies on 
external self-inflating element 72 to pull on the outer surfaces of the 
chambers and passages, reducing the pressure inside if they have been 
previously collapsed. Air or liquid is then drawn in through valve 83. 
In a preferred embodiment of this mattress, valve 83 automatically passes 
air or liquid into the chambers of the mattress, and passes air or fluid 
out of the chambers only when manually activated. Self-inflating element 
72 of this mattress is designed to overinflate the chambers. A user then 
lies down on the mattress, and opens valve 83. His or her weight drives 
fluid out of the mattress, and the valve is closed when a comfortable 
volume of fluid remains in the chambers. This embodiment has the 
adjustable body profile conforming elements of other embodiments, i.e., 
head chamber 20, passage 25, lumbar chamber 28, passage 27, and thigh 
chamber 32. 
Operation--FIG. 10 
The embodiment of FIG. 10 is an inflatable mattress with no foam or other 
insulative or self-inflating elements, and no separate chambers. The range 
of adjustment of such a mattress is limited by its thickness. If too thin, 
the back and buttocks tend to bottom out at lower inflation pressures. 
This mattress may be the least expensive to manufacture in large 
quantities. However, it requires a large volume of pressurized air for 
inflation and has less effective thermal insulation characteristics. 
Operation--FIG. 11 
The mattress of FIG. 11 can have a wider range of adjustment than that of 
FIG. 10, due to the separate inflatable chambers 22, 30, and 34. There is 
also less tnedency for a user to "bottom out" on this mattress. For 
instance, it can be appreciated that when a user reclines on the mattress, 
back chamber 22 and seat chamber 30 will be compressed without 
communication to the whole mattress, as occurs in the embodiment of FIG. 
10. This results in a steeper pressure gradient in these chambers than in 
equivalent regions in FIG. 10, or a greater rise in pressure/resistance 
under deformation. 
Operation--FIG. 12 
The mattress of FIG. 12 comprises six separately inflatable chambers or 
chambers. It can be adjusted for comfort in a particular reclining 
position, such as lying supine, but may not be optimum for another 
position, such as lying on one's side, without further inflation and 
deflation of various chambers. This is due to the limited volume of each 
chamber. It can be appreciated, for instance, that, due to the lack of 
interconnection between head chamber 20, lumbar chamber 28, and thigh 
chamber 32, head chamber 20 will not change volume and so height when one 
shifts from lying on one's back to lying on one's side, and vice versa. 
Also, lumbar chamber 28 may have a comfortable, supportive height when one 
is reclining supine, but may be a very uncomfortable bulge when one is 
prone. The separately inflated chambers can be useful where the user is 
generally supine, as on a lounge chair, where the lightness of an 
inflatable is desirable, or where reliable buoyancy is necessary, as in a 
mat that also serves as an emergency float. 
Operation--FIG. 13 
The mattress of FIG. 13 is similar to that of FIG. 12 in that it has 
separate compartments, but, since it has no inflatable elements, it would 
not have the adjustability of the mattress of FIG. 12. However, such a 
design is very useful where the user is generally supine, as on a chaise 
lounge, or in use as a pool float, where the buildup of resistance would 
be moderated by the tendency to sink into the supporting medium, and where 
the simplicity of a non-inflatable mattress is preferable over the 
lightness of an inflatable such as that of FIG. 12. 
Operation--FIG. 14 
The homogeneous construction of FIG. 14 can be employed in either an 
inflatable or non-inflatable embodiment. As an inflatable, a very soft, 
low-density, open-celled, flexible urethane foam 170 has air-tight coating 
or fabric 168 bonded or adhered to it. 
Adhesion of an air-tight skin to substantially the entire surface of the 
foam core is necessary to prevent "billowing." Billowing occurs when an 
air-tight covering or skin is not bonded to a contained core: when the 
inflatable is pressurized or deformed, increased air pressure causes the 
covering to separate from the core and assume a rounded contour. It can be 
appreciated that if an air-tight skin or covering surrounds a flat, 
flexible core, under inflation the skin will tend to assume a rounded 
cross-section. If the skin is not bonded to the core, an increase in 
volume of the inflatable will result. If the contained air in an 
inflatable of generally flat configuration, such as a mattress, has no 
greater volume than the unattached core, the air will furnish no 
cushioning support, due to billowing, or an unrestrained increase in the 
volume of the inflatable with very small pressure change. When the 
air-tight skin is bonded to the core, billowing does not occur, and 
support pressure within the inflatable mattress rises in direct proportion 
to the deformation of the mattress. 
Valve 167 penetrates skin or covering 168. The mattress self-inflates, and 
can be further pressurized as desired. This embodiment has the advantage 
of being simple to manufacture, has only a single inflation valve, and can 
be deflated and rolled into a cylinder for storage. The use of a soft foam 
170 improves the conformity of this mattress or pad to a variety of body 
positions, as the foam offers little resistance when deformed. However, 
head region 172 will not vary in height with various positions as with the 
mattress of FIGS. 1-4, and there may be a tendency for the back and 
buttocks to bottom out under low inflation pressures, as with the 
single-valve inflatable mattress of FIG. 10. 
As a non-inflatable mattress, pad, or cushion, a firm flexible foam or 
other resilient material 170 is enclosed by a fabric or cover 168, and has 
no valve 167. As this embodiment has limited conformity to a variety of 
body positions as do the mattresses in FIGS. 12 & 13, it is best suited 
for comfort in the supine position. Due to its simplicity, it will have a 
low manufacturing cost, and is therefore very attractive for limited 
applications, such as in a chaise lounge, where the user reclines in the 
supine position. 
While the above descriptions contain many specificities, these should not 
be construed as limitations on the scope of the invention, but rather as 
an exemplification of preferred embodiments thereof. Many other variations 
are possible, for example having single passages between chambers, having 
the seat chamber connect to the lumbar chamber, and other variations not 
limited to those mentioned here. 
For instance, a separate chamber can be provided under the knees, which 
interconnects with a chamber at the foot. When the user is supine, the 
space behind the knees is filled and supported. When the user turns on his 
or her side, fluid moves out of the knee chamber as it is pressed by the 
side of the knee or foreleg. 
Another example would be a mattress similar to that described, with an 
additional chamber at the head end. This would cradle the neck and head 
over a wider range of body types, and allow more air to transfer from the 
head and neck chambers to the small of back and thigh chambers. 
Yet another example would be the addition of further interconnected 
chambers and valves to block air flow between selected chambers. This 
could include the collapsing or expanding of chambers to vary the length 
of the mattress. 
Still another example would be the use of closed chambers and 
interconnected, dimensioned chambers in a thicker mattress, including one 
with conventional I-beam construction, longitudinal inflatable elements, 
or water compartments. 
In a thicker mattress, the chambers could be deeper and more resilient than 
those shown. There could be a contoured pad beneath the chambers, said pad 
having a concave bottom surface beneath the lumbar chamber to allow 
greater depth for the abdomen of a prone individual. Also, there could be 
a sloping depression from the calves to the feet, allow these portions of 
the body more comfort, especially when blankets or covers are draped over 
them. 
Also, it can be appreciated that an embodiment of this mattress can be used 
as a water float or as the padding or upholstery of a chair, auto seat, 
couch, chaise lounge, a convertible (sitting, lying, or lounging) 
furniture piece, etc. 
Accordingly, the full scope of the invention should be determined not by 
the embodiments illustrated, but by the appended claims and their legal 
equivalents.