U.S. patent number 3,922,801 [Application Number 05/379,726] was granted by the patent office on 1975-12-02 for liquid filled orthopedic apparatus.
Invention is credited to Patrick Thomas Zente.
United States Patent |
3,922,801 |
Zente |
December 2, 1975 |
Liquid filled orthopedic apparatus
Abstract
An apparatus and method of making it is provided whereby a
liquid-filled shoe insole is produced. The insole comprises
discreet internal liquid-filled ampules which are strategically
placed between upper and lower laminae and sealed in place to
provide separate support for various parts of the foot.
Inventors: |
Zente; Patrick Thomas (West
Orange, NJ) |
Family
ID: |
23498428 |
Appl.
No.: |
05/379,726 |
Filed: |
July 16, 1973 |
Current U.S.
Class: |
36/44 |
Current CPC
Class: |
A43B
13/20 (20130101) |
Current International
Class: |
A43B
13/18 (20060101); A43B 13/20 (20060101); A43B
013/40 () |
Field of
Search: |
;36/44,29,3R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Guest; Alfred R.
Claims
I claim:
1. An apparatus for treating foot defects and for promoting foot
comfort which comprises:
flexible, liquid-filled ampules, at least one separate ampule being
provided and positioned to support each of (a) the toes, (b) the
metatarsal, (c) the arch, and (d) the heel; and
a flexible upper lamina and a flexible lower lamina, the laminae
containing the ampules, and the laminae being sealed at their
periphery and around the perimeter of each of the ampules, thereby
permanently positioning the ampules and forming the apparatus.
2. The apparatus of claim 1 in which the liquid is mineral oil.
3. The apparatus of claim 1 in which (a) 2 ampules are provided for
the toes, (b) 3 ampules are provided for the metatarsal, (c) 2
ampules are provided for the arch, and (d) 2 ampules are provided
for the heel.
4. The apparatus of claim 3 in which one of the ampules provided
for the heel is substantially toroidal in shape, the other being
substantially cylindrical and positioned centrally inside said
toroidal ampule.
5. The apparatus of claim 1 in which one ampule is provided for the
heel, said ampule being substantially toroidal in shape.
6. The apparatus of claim 1 in which two ampules are provided for
the metatarsal.
7. The apparatus in claim 1 in which the liquid is water.
Description
Orthopedic researchers have over the years developed numerous ways
to modify shoes for both remedial and preventative reasons. Arch
supports, for example, have long been known to enhance the support
a shoe affords persons with weak arches. Pads can be placed in
shoes to enhance the comfort of a wearer who suffers pain at the
metatarsal. Wedges can be placed in the inside or outside edges of
soles or heels to afford a variety of canting to counter many
abnormalities of the foot such as "toeing in" or "toeing out", and
the like.
Also widely employed are various types of shoe insoles which can be
purchased separately from the shoes and installed by the wearer.
Generally, such insoles are of two types, those sold by retail
merchants and those purchased in accordance with medical
prescription. The former usually consist of no more than a soft
foam synthetic or rubber and are employed to soften or cushion the
feel of the shoe. Although these have enjoyed a reasonable amount
of success in the marketplace, the purchaser soon learns of serious
disadvantages inherent in such devices. Soon after he begins to
wear them he finds that, for reasons including heat, perspiration
and wear fatigue, the foam material in the insole compresses and
loses its cushioning ability, thereby becoming useless. In
addition, these devices have a tendency to absorb moisture without
dissipating it. The cellular nature of the foam contains this
moisture. Thus precluding rapid drying during periods of non-use.
Consequently, the wearer often finds himself wearing damp shoes, a
situation which enhances the probability of such disadvantages as
odiferousness and a fungus infection closely akin to ringworn known
as "athlete's foot."
Prescription insoles, on the other hand, are expensive and rarely
confortable, being generally constructed on a rigid backing,
usually leather-covered metal. Because they lack an inherent
flexibility, the wearer experiences chafing and pressure,
especially in the areas of the heel, arch and metatarsal.
Many attempts have been made to avoid these prior art limitations,
including the use of liquid fillers, but all have been plagued by
one or more undesirable flaws. Indicative of such attempts are U.S.
Pat. Nos. 532,429; 1,069,001; 1,193,608; 1,148,376; 1,517,171;
2,546,296; and 2,549,343. These patents teach the use of
interconnected fluid compartments filled with air or liquids, foam
soles and insoles, honeycomb sole structures, and air-filled outer
soles. However, none of these references suggest either the unique
structure and method of making the present invention nor the
unexpectedly superior results which have been achieved by the
present invention.
Despite these and other numerous attempts at enhancing orthopedic
therapy and comfort, there has yet to be devised a method of
satisfactorily combining all of the desirable features into a
single durable insole. To solve this problem, a comprehensive
research and development program was engaged in to devise such an
insole, taking into consideration the specific sources of
discomfort which are common to most sufferers of foot maladies. In
the course of this work, the present invention was discovered.
Briefly stated, this discovery comprises encasing a liquid medium
in a soft, flexible material such that the liquid is encased in
strategically located, mutually exclusive, discrete compartments or
ampules. These ampules are contained between flexible laminae to
provide a shoe insole shaped to substantially conform to the inside
bottom of a shoe. More specifically the invention comprises a
flexible upper lamina and a flexible lower lamina which are joined
at their periphery to form a flexible shoe insole. Inside or
between the laminae are flexible, liquid-filled ampules which are
fixed in position to support various parts of the foot. At least
one separate ampule is provided to support each of (a) the toes,
(b) the metatarsal, (c) the arch, and (d) the heel.
Specific embodiments of this invention are shown in the Figures.
FIG. 1 is provided to show an insole of the present invention
containing 11 ampules in a preferred spatial arrangement to provide
maximum support for the toes, metatarsal, arch and heel. FIG. 2
depicts the separate ampules utilized in a preferred embodiment and
their individual shapes. FIG. 3 illustrates the formation of the
bottom lamina during manufacture of the insole. FIGS. 4a and 4b are
cross-sectional views of the heel portion of FIG. 1 along the line
4--4. FIG. 5 shows a die or template which can be used in making
the ampules and lower lamina.
FIG. 1 shows a preferred embodiment in which ampules 1 and 2 are
provided to cushion the toes, ampules 3, 4, and 5 are provided for
metatarsal support, ampules 6 and 7 render arch support and ampules
8 and 9 cushion and support the heel. In another preferred
embodiment, ampules 17 and 18 are provided to further support the
arch and outside edge of the foot.
The construction of the insole is illustrated by FIG. 4a and 4b
which are cross-sectional views of the heel section along lines
4--4 of FIG. 1. Upper lamina 10 is joined and sealed to lower
lamina 11 at points 12, 13, and 14. Point 12 is the junction
between the outer edges or periphery of the laminae whereas
junctions at points 13 and 14 serve to permanently place and seal
the heel ampules 8 and 9. Hence, ampule 8 is substantially toroidal
in shape, whereas 9 is substantially cylindrical. Of course, ampule
9 may take on equivalent shapes such as ovoid. Alternatively,
ampule 9 may be omitted as shown in FIG. 4b. In this embodiment,
toroidal ampule 8 is sealed between junctures of the upper and
lower laminae 12 and 15, the latter seal defining a circular area
central to the toroidal ampule 8.
All of the ampules are substantially filled with liquid 16
illustrated in FIGS. 4a and 4b. The liquid filler may be selected
from numerous media including water; alcohols such as ethanol,
isopropanol, n-hexanol, cyclohexanol, trichloroethanol, lauryl
alcohol, n-octanol, and n-decanol; esters such as ethyl acetate,
isopropyl formate, methyl and ethyl propionate, and isopropyl
acetate; halogenated compounds such as dichloroethylene,
chloroform, and carbon tetrachloride; and oils such as mineral oil
and silicon oil. It will be appreciated by a skilled artisan that
the choice of liquid filler is dictated by the specific parameters
of intended use and materials of construction. Hence, depending on
the hydrodynamics desired for a particular use, a liquid of
relatively low viscosity may be chosen. Alternatively, it may be
desirable to use a liquid of relatively high viscosity such as a
mineral oil or a higher alcohol or ester. Of course, any liquid
mixture may be employed which satisfies the requirements of
viscosity and compatibility with materials of construction. For
example, if the insole is constructed of polyvinyl chloride (PVC),
one would not employ as a filler a liquid which is a solvent for
PVC or which would leach out the plasticizer in the PVC. Although
the range of usable liquids is practically limitless, it is
preferred to use water or mineral oil because of (a) their low cost
and (b) their harmless nature with respect to human skin should the
construction material fail and the liquid contact the wearer's
foot.
Equally broad is the selection of material from which the laminae
and ampules are constructed. This material should be soft and
pliant. It should be strong enough to withstand constant flexing
under the weight of the wearer. Illustrative of these are rubber,
foamed rubber, ABS copolymers, polyethylene, foamed polyethylene,
polyvinyl choride and its copolymers, polyurethane, foamed
polyurethane, polyisobutylene, and polyisoprene. Also of use are
various resin mixtures and copolymers which fall within the
framework of softness, strength and compatibility with the filler
liquid. In addition, the construction material must lend itself to
sealability so that permanent seals between laminae can be
achieved.
Broadly, the insole is made by first forming liquid-filled ampules
of the shape desired for the specific orthopedic functions desired.
These ampules are then placed between two outer laminae which are
shaped to conform to the insole of a shoe. The laminae are then
sealed together to permanently position the ampules.
A particular method for making the invention is described as
follows:
A die such as that illustrated in FIG. 5 is fabricated from brass
and mounted in an aluminum base 20. The die 21 is shaped in
accordance with a particular shoe size which is defined by raised
ridge 22 which extends peripherally around the insole outline.
Inside the raised periphery portion are other ridges or raised
portions such as 23, 24 and 25 which define concave sections which
correspond generally to the desired ampule shapes. At the bottom of
each concave section, a hole is drilled completely through the die
and its base. The purpose of these holes are to enable vacuum
forming as will become evident, infra.
To form the ampules, a first lower lamina of flexible material
impervious to the liquid to be employed as a filler is placed over
the die. A heat source sufficient to soften the material is applied
from above while simultaneously, a vacuum is drawn from the bottom
of the die. Upon removal of the heat source and cooling, the first
lower lamina now conforms to the shape of the die having raised
ridges defining first concave sections congruent to those of the
die. Such a formed lamina is depicted by FIG. 3.
Next, the concave sections are filled with the liquid to be
employed and the first lower lamina, while still in place on the
die, is covered by a first upper lamina. The two laminae are then
sealed at their periphery and at the raised portions, utilizing any
of the numerous known methods such as heat fusion, pressure
sealing, cement, high frequency sound waves, etc. One preferred
method is by use of a 11/2 kilowatt high frequency generator
manufactured by Sealomatic Electronics Corporation of Brooklyn,
N.Y. The finished ampules are then removed from the die and are
left intact as a unitary structure or separated from each other by
seal tearing. Hence, the first laminae may be sealed to facilitate
tearing to separate the ampules.
A second lower lamina is then formed in the same way as the first
lower lamina. The same or a slightly larger die can be used for
this purpose and the finished second lower lamina is shaped to
provide raised ridges defining second concave sections which
conform substantially identically to the ampules and to the first
concave sections. The ampules are then placed on the second lower
lamina such that each ampule fits into its respective second
concave section. The emplaced ampules are then covered with a
second upper lamina which is sealed to the second lower lamina at
their periphery and at the raised portions thereby completely
enclosing the ampules and permanently positioning them.
The following example is provided to further illustate the present
invention.
EXAMPLE
A sheet of polyvinyl chloride manufactured by Union Carbide
Corporation under the trademark "Krene", specification No.
KDA-2088, which is pinhole-free and having a thickness of 8-20 mils
was laid over a die as described supra and shown in FIG. 5. Heat
sufficient to soften the material was applied from above and a
partial vacuum was applied to the base of th4 die. After the
softened PVC had conformed to the die, the heat source was removed
and the shaped PVC was cooled by spraying it with compressed air at
ambient temperature. The molded sheet was then flooded with water
to fill the concave sections formed in it.
Another sheet of the same material was then placed over the
water-filled sheet and die and sealed in a 11/2 kilowatt high
frequency generator manufactured by Sealomatic Electronics
Corporation. Upon removal from the sealing generator, the sealed
ampules produced were separated from each other. The separated
ampules conformed in shape substantially to FIG. 2 which depicts
the separated ampules.
Next, a sheet of the same PVC material was placed over the same
die, and formed by application of heat and vacuum substantially as
above. After cooling this formed sheet with compressed air, the
separated ampules were each placed in their correspondingly shaped
concave sections and covered by another sheet of the same PVC. The
ampules were then sealed between the PVC sheets using the above
high frequency generator. After sealing, the finished insole was
removed from the sealing unit and excess PVC was trimmed from the
insole periphery.
Other features and embodiments of the present invention will be
apparent in light of the foregoing discussion. The foregoing
example is presented as merely illustrative of a preferred
embodiment and is in no way meant to limit the invention.
* * * * *