Note: Descriptions are shown in the official language in which they were submitted.
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1 FIELD OF INVENTION
This invention relates to waterbeds and finds particular application
to the damping of the wa~e action of the fluid within a waterbed mattress.
BACKGROUND OF THE INVENTION
Many attempts have been made to reduce the effect of the wave
motion in a waterbed mattress generated by a user reclining on the waterbed
mattress. Particularly, many attempts have been made not only to minimize
the initial wave generating, but also the transmission of the waves through
thè fluid, and their ultimate reflection from the side walls of the mattress
10 and frame.
Additionally, for maximum damping effect, the proposed method should
reduce wave motion and attenuate its amplitude. Early attempts to damp water
wave motion propose the use of suspensions, gels, soluble viscosity increasing
agents (See U.S. Patents 3,585,356; 3,787,908 and 3,810,265); an air bag
15 anchored to the bottom of a waterbed mattress (See U.S. Patent 3,746,835);
connectors extending between the top and bottom sheets of a waterbed mattress
to tie the sheets together (See U.S. Patent 4,167,795); hanging baffles secured
to the top sheet of the waterbed mattress (See U.S. Patent 3,736,604);
floating baffles extending upwardly from the bottom sheet to provide a wiping
20 contact with the top sheet of the waterbed mattress when a user sits on it
(See U.S. Patent 5,204,289), a floating foam pad anchored to the bottom sheet
and floating upwardly proximate the top sheet (See U.S. Patent 4,247,962); a
relatively stiff peripheral cushion of foam proximate the inner peripheral walls
of the waterbed mattress together with a resilient open cell foam filling the
remainder of the cavity of the mattress (See U.S. Patent 4,245,361); and non-woven
or very loosely woven expanded fiber product, unbonded or fixed with a binder
sitting within the waterbed mattress cavity (See U.S. Patent 4,301,560).
However, these proposals are plagued with problems from the
necessity of providing watertight seams at high stress points as in the
proposal in U.S. Patent 4,1677795 being bulkiness, poor handling when stored
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1 and when drained for storage, to ineffectiveness.
In the most recent proposal, (U.S. Patent 4,301,560) the "non-woven
or very loosely woven" (words of the Patentee) fiber product, because its specific
gravity is greater than 1, sits on the bottom sheet and unless of substantial
s thickness, does not provide satisfactory damping of the wave motion.
Additionally, because the fiber product sits on the bottom sheet
over the heater, it tends to concentrate the heat produced by the heater at the
bottom of the waterbed mattress and does not permit the convection currents
normally created within the waterbed mattress to circulate the heat thus
lQ creating a potentially hazardous situation.
On the other hand, closed cell foam used by itself, either in a
freely floating pad or in pieces, floats in the fluid proximate the top sheet
and engages the undersurface of the top sheet, thereby reducing the water
support for, and thus the comfort of, the user.
It is therefore an object of this invention to provide an improved
damping structure which safely acts in the path of wave motion to effectively
damp the wave motion and attenuate its amplitude.
Further and other objects of the invention will be realized by
those skilled in the art from the following summary of the invention and de-
20 tailed description of preferred embodiments thereof.
SUMMARY OF THE INYENTION
Surprisingly, when a damping structure is incorporated into awaterbed mattress and which structure comprises vertically extending tubular
structures or "coils" secured to the bottom sheet of the waterbed mattress,
25 having secured proximate the top of each tubular structure or "coil", closed
cell light density foam material, and terminating a predetermined distance below
the top sheet of the mattress, and fiber product with loft that doesn't de-
compose in water, either unbonded or bonded with resin in situ in the space
between the top of the tubular structure and the undersurface of the top sheet
of the mattress and extending under a substantial portion of the top sheet of
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1 the mattress, the reduction of the wave motion and the attenuation of the
waves is significant, both taking place in a shorter period of time than
previously provided. The "coils" are distributed about the bottom of the
mattress and are sufficent in number to support or carry the heavier than
water fiber product (which fiber product usuall~ has a specific gravity of
about 1.2 to about 1.5). The "coils" or tubular structure may have apertures
thr~ugh their side wall for the passage of water therethrough.
By the expression fiber product with loft the inventor includes
any incompassed fiber product with height that is resilient and resists com-
10 pression.
In a queen size mattress manufactured, 48 floating coils are employedequally distributed about the bottom of the waterbed mattress and 40 denier
fiber product is disposed in the space between the top of the coils and top
sheet of the mattress.
The fiber product is preferably cut in lengths and widths from a roll
of such product. For example 100~ polyester fiber ~6 denier and 18 denier blend)
in 72" wide rolls may be cut in desired lengbhs and trimmed as required.
The invention will now be illustrated with reference to the following
drawings of the preferred embodiments of the invention.
20 BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view partly in section of a waterbed
mattress constructed according to a preferred embodiment of the invention.
Figure 2 is a close up side elevational view of part of the structure
shown in Figure 1.
Figure 3 is a close up perspective view of part of the damping struc-
ture shown in Figure 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the said Figures, there is shown queen size waterbed
mattress 10 of vinyl, comprising damping structure 12, comprising 48 vertically
e,~tending tubular structures or "coils" 14 sealed at one end to the bottom
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1 sheet 16 of the waterbed mattress, each having apertures 15 therethrough for the
oassage of the water and carrying on its upper end, discs or round pads 18 of
closed cell light density polyethylene for floating the tubular structures
upwardly. Tubular structures 14 comprise the same material as the outer sheet
material of -the waterbed mattress 10, and are dielectrically sealed to the
bottom sheet equidistant from one another in 6 rows of 8 "coils". A pad of
fib~r product with loft approximately 1~2 inches high of 40 denier Dacron (t.m.)
Fiber bonded with an acrylic adhesive and having a specific gravity of between
1.2 and 1.5 sits on the coils and, carried by the floating "coils" extending
10 under substantially all of the undersurface 19 of the top sheet. Each coil
is made of vinyl material and has a length of 6 incnes (152.4 mm) and a diameter
of 6 inches (151.4 mm) and carries a ~" (12.70 mm) thick disc of POLYFOAM (t.m.)
light density polyethylene foam.
~ith this configuration, the duration of decay of waves generated in
15 the waterbed mattress and peak amplitude of the wave is minimized and thus
is of less effect on the user of the bed than prior art proposals.
As many changes could be made to the invention without departing from
the scope of the invention, it is intended that all matter contained herein be
interpreted as illustrative of the invention and not in a limiting sense.
