Contoured foam mattress

A foam mattress having a crown area with cored-out areas therein to modify the harshness of feel of said mattress.

This invention relates generally to a cushion. More particularly, it 
relates to a high comfort mattress having a smartly tailored look. 
The foam rubber or plastic cushion generally has a foam core with a cover 
thereon or enclosed therein. These foam rubber or plastic cushions and 
especially those made from polyurethane foam have a feeling of hardness 
when the load is low, such as when the cushion is first encountered by the 
body. Thus, when sitting down or lying down on such a cushion or mattress, 
the occupant has the sensation of first encountering a hard shell and then 
suddenly breaking through. This sensation can be varied by changing the 
density of the foam but this effects the comfort factor after the initial 
encounter. 
It is accordingly an object of this invention to provide a novel mattress 
construction of foam which is of light weight and yet constitutes a medium 
on which one can rest with comfort and without the above-mentioned 
physical sensations.

Referring to FIG. 2, the rectangular foam mattress 3 of the crown type is 
enclosed in a decorative mattress cover and the crown 4 of the mattress 
rises in the normal manner to give a gradual slope upward of one to about 
10 degrees from the corner 5 of the longitudinal edges 6 of the mattress 
to the center thereof. The depth, length and width of the mattress is more 
or less conventional, depending on whether the mattress is for a single, 
double or king size bed. 
The perspective view of FIG. 1 shows the center portion 7 lying between the 
border strips 7A in the top portion 8 of the mattress which has a series 
of interconnected grooves creating a hexagonal pattern 9 therein. These 
interconnected grooves being about one to eight inches and preferably 
three inches from the longitudinal edges 5 to leave a border strip 7A 
between the edge and the grooves. This arrangement of the grooves in the 
top portion of the core gives the mattress added strength in the outer 
edges and reduces the tendency to roll off the mattress due to the crown 
effect. Also, the hexagonal pattern of the grooves prevents the cover 11 
of the mattress from tucking into the grooves and presenting an unsightly 
appearance of the cover over or enclosing the foam pad. Furthermore, when 
the diagonal grooves run at a bias to the border strips, they give the 
mattress a unique appearance and avoid the weight of two people lying on 
the mattress being concentrated in the same horizontal row. 
Preferably the grooves have a tapered or V-shape 12, as seen best in FIG. 
2. For instance, the grooves preferably are one and one-fourth inches deep 
and vary from about five-sixteenths to about nine-sixteenths inch wide at 
the top of the mattress to about one-sixteenth to about three-sixteenths 
inch at the bottom of the groove. Also, the hexagonal figures are 
preferably one to seven-sixteenths inch on a side. In general, it is 
desired that the length of the grooves in the groove pattern in the crown 
portion of the foam core be in short nonparallel lengths which are 
continuous for no more than four inches and preferably one to two inches 
before the groove changes directions. Thus, where the grooves run in short 
lengths before changing directions, the noncored-out portion can yield 
readily to loading to give a soft feed initially and as the raised 
portions are compressed can progressively resist compression to give a 
mattress having the ability to fit the body contour and giving a very 
pleasing feeling and yet the cover has a pleasing appearance. 
As the number of sides to the raised portions increases it becomes a circle 
and in some aspects a nested circular pattern resists the cover tucking 
into the coredout grooves as well as the hexagonal pattern. The grooves 
can describe any geometric pattern so long as they intersect and the 
straight lengths are less than four inches and the noncored or raised area 
can be deflected initially as independent units. 
EXAMPLE 
A mattress mold 15 of rectangular shape fitted with raised members or gates 
16 to give a hexagonal cored out or grooved effect in the crown area was 
used to cast a mattress. The mattress was poured by the pouring head 17 
that gives a fan-shaped pour pattern 18. Preferably two or more pouring 
heads are utilized as necessary dependent on the size of the article, that 
can pour a fan-shaped pattern. In FIG. 3 three pouring heads are shown, 
each head being of the type described in U.S. Pat. No. 3,927,162. These 
three puring heads pour a fan-shaped pattern that yields a crown-shaped 
mattress having the desired hexagonal grooved pattern with no air 
entrapment or large bubbles obtained with other pouring heads. 
Once the polyurethane foamable reaction mixture of polyether polyol and an 
organic polyisocyanate and sufficient water to give a foam preferably of 
2.5 to 3.5 density is poured into the mold, it is closed with a suitable 
lid. The foamable reaction mixture is allowed to foam and cure before the 
mattress core is stripped from the mold. The mattress core has a geometric 
pattern of grooves or cored-out areas having lengths no more than about 
four inches before it terminates or changes directions. Thus, the 
noncored-out portion of the crown area can be compressed individually for 
at least 10 percent of its height before adjacent noncored-out areas begin 
to deflect. 
This method of making a foam mattress permits it to be made with relatively 
high crowns, usually one-half to one inch in the center, without the 
person lying on the mattress feeling he is rolling off of it. 
To recapitulate, this method of making the mattress core comprises 
effecting relative movement between a pour means, preferably two or more 
pour heads, and a mold having a cavity with a mattress crown configuration 
in the bottom thereof. This curvature of the cavity to achieve the 
mattress crown configuration is divided by suitable gates or raised 
portions to give a cored-out pattern in the crown of the molded product, 
for instance, a series of truncated pyramids or hexagonal members. The 
polyurethane mattress type foam reaction mixture is distributed in a 
fan-shaped arc in response to the relative movement between the pouring 
means and the mold to distribute the mixture from one end and over the 
gates to the other end of the mold. This relative movement may be achieved 
by manually moving the mold or the pouring means relative to each other or 
by apparatus such as described in U.S. Pat. No. 3,247,295 of J. E. 
Burwell. After the formable liquid polyurethane reaction mixture of the 
mattress grade is distributed over the mold the mold is closed and the 
mixture allowed to foam full and cure within the mold before removing the 
molded core from the mold. 
While certain representative embodiments and details have been shown for 
the purpose of illustrating the invention, it will be apparent to those 
skilled in this art that various changes and modifications may be made 
therein without departing from the spirit or scope of the invention.