US 3724106 A
An insole structure for footwear comprised of upper and lower surfaces which form one or more internal cavities within the body of the structure, the cavities so formed containing a fluid such as water, air or a gel, providing thereby a durable and comfortable means for cushioning and supporting the feet inside footwear such as shoes, sandals, slippers and/or boots. The present invention may find embodiment in (i) a flexible contoured insole designed for insertion into conventional footwear or (ii) in footwear having the invented insole structure built into and made and integral part thereof. The shape, location, height, etc., of the cavities can be designed to achieve particular therapeutic objectives such as the support of weak arches.
Description (OCR text may contain errors)
United States Patent [191 Magidson I 51 Apr. 3, 1973 54] INSOLE STRUCTURE  Appl. No.: 158,018
 US. Cl ..36/44  Int. Cl. ..A43b 13/38  Field of Search ..36/44, 29
 References Cited UNITED STATES PATENTS 3,120,712 2/1964 Menken ..36/29 2,084,517 6/1937 Vogel ..36/29 X 2,477,588 8/1949 Dumm.... .....36l44 UX 1,869,257 7/1932 I-Iitzler.... ..36/29 X 3,449,844 6/1969 Spence... ..36/44 2,677,906 5/1954 Reed ..36/44 X 3,589,037 6/1971 Gallagher ..36/44 2,221,202 11/1940 Ratcliff ..36/44 UX 2,762,134 9/1956 Town ..36l44 UX 1,712,387 5/ 1929 Kajiyama ..36/44 FOREIGN PATENTS OR APPLICATIONS 856,622 12/1960 Great Britain. ..36/44 Primary ExaminerAlfred R. Guest Attorney-Spensley, Horn & Lubitz [5 7] ABSTRACT and lower surfaces which form one or more internal cavities within the body of the structure, the cavities so formed containing a fluid such as water, air or a gel, providing thereby a durable and comfortable means for cushioning and supporting the feet inside footwear such as shoes, sandals, slippers and/or boots. The present invention may find embodiment in (i) a flexible contoured insole designed for insertion into conventional footwear or (ii) in footwear having the invented insole structure built into and made and integral part thereof. The shape, location, height, etc., of the cavities can be designed to achieve particular therapeutic objectives such as the support of weak arches.
4 Claims, 9 Drawing Figures PATENIEDAPRB ms 3.724.106
SHEET 1 BF 3 HEPEK/Qr MAG/060M INVENTOR.
INSOLESTRUCTURE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to the field of footwear, and more particularly to insoles and innersoles for foot cushioning and/or supporting structures.
2. Prior Art The use ofinsoles for enhancing the comfort of footwear is not new. The prior art shows a number of such structures. One type of insole disclosed by the prior art is the foamed rubber thermoplastic insole designed to be inserted into the wearers footwear. This type of insole is typically comprised of a sheet of cushioning material (e.g., foamed rubber) layered with one of a pair of relatively thin outer sheets of suitable material. In another structure of this type the cushioning material may be fully enclosed within an outer structure. Regardless of their variations, insoles of this type all suffer from the Same disadvantage, to wit: the deterioration and/or compression of the cushioning material and the resultant loss of resilience thereof. In some cases the cushioning material may even desintegrate, rendering the insoles useless as well as uncomfortable due to lumps and voids therein.
Another type of prior art insole is the medicated insole having encapsulated within an outer structure one or more medicating materials such as (i) foot powder or (ii) rupturable plastic capsules containing scented, cooling, germicidal and/Or fungicidal substances. Insoles of this type typically have an upper section made of a porous material in order to allow the powder or other appropriate substance to pass through to the users feet. These insoles have the disadvantage of higher cost because of the necessary inclusion therein of the consumable material. The prior art discloses means for replenishing the supply of powder or other consumable material in this type of insole. As a result, however, the user must bear the cost of continual replacement of the material in order to continue to use the insoles. On the other hand, some of the structures disclosed by the prior art provide no means for replenishing the consumable material. In these cases, when the consumable is depleted, the entire insole becomes useless and must be replaced.
A further disadvantage of medicated insoles is they provide little cushioning of the feet. This is because they are conceived and designed primarily as dispensers of powder or other medicated substances and not as foot cushioners. In the first place, powders and small plastic capsules have little resilience; secondly, because of internal shear forces, powder and plastic capsules cannot rapidly and uniformly distribute the pressure applied by the weight of the user. As a result, insoles of this type lack good cushioning characteristics.
The present invention overcomes these shortcomings of the prior art by disclosing a novel structure which utilizes a fluid, such as, for example, water, as the cushioning medium encapsulated within one or more cavities within the body of the structure. Unlike the prior art insoles which use foamed rubber or foamed thermoplastic material, the fluid used in the present invention does not deteriorate or compress under the temperature, pressure, and Moisture conditions to which insoles aresubjected. In addition, unlike the medicated insoles, the Present invention does not utilize or rely upon relatively expensive and consumable materials in order to have a comforting effect upon the feet. And, further, the use of a fluid as the cushioning medium results in a more comfortable insole than that which is possible when powder or small plastic capsule-s are used. This result is attributable to the well knoWn physical property Of fluids under pressure, to wit: the property of distributing the applied pressure uniformly and almost instantlythroughout the fluid. Thus, the encapsulated fluid immediately redistributes itself within its cavities so that (i) the upper section of the insole conforms to the contour of the bottom surface of the users foot where these surfaces are in contact; and (ii) the supporting force provided by the fluid is applied uniformly over the contacting surface of the users foot. As a result of this property of fluids, the present invention provides a highly comfortable sensation to the user, a sensation which has heretofore not been achievable.
SUMMARY OF THE INVENTION The present invention is a novel insole structure which cushions and supports the users feet during the wearing of footwear such as shoes, sandals, an integral and/or boots. The present invention insole can either be an integral part of the item of footwear or a separate structure designed for insertion into footwear.
The present invention is comprised of upper and lower contoured surfaces which together form one or more internal cavities within the body or the structure. The cavities so formed contain a suitable fluid, such as water, which serves as the cushioning and supporting medium of the insole. The fluid within the cavities is entrapped; since it is normally unable to escape, the fluid lasts for the life of the insole structure. The fluid filled cavities can be located so as to provide support to particular portions of the foot.
The invention insole structure achieves its unique cushioning and supporting effect by utilizing the well known property of fluids; i.e., the property of distributing applied pressure uniformly and almost instantly throughout the fluid. Thus, when the users weight is applied to the invented structure the fluid in the cavities immediately redistributes itself therein causing the upper surface of the insole to conform to the bottom contour of the users foot where these surfaces are in contact, while, at the same time, supporting the foot with uniform pressure over its contacting surface. The effect is a pleasantly cushioned but firm sensation of comfort While wearing footwear.
The benefits of the present invention are not limited to providing comfort to wearers of footwear. The invented insole structure can also have a therapeutic effect upon feet which are not healthy in one or more respects. The shape, location, contour and height of the cavities, and the elasticity of the insole material can be selected so as to provide the-degree of cushioning and support which is desired'to those portions of the foot where it is needed. For example, the invented insole can readily be configured to provide support to weak arches.
In practicing the present invention embodiments thereof can be either structurally independent of the item of footwear or anintegral part of it. In the former case the invented insole is contoured to be inserted into and to fit properly in a corresponding sized shoe, slipper, etc.
Embodiments of the present invention which are structurally independent of the footwear are comprised of relatively thin upper and lower contoured surfaces made of a flexible non-porous material, such as polyethylene, vinyl or elastomeric plastic. In some embodiments of this type, the upper surface is flat and has an outer contour which conforms to the contour and style of the footwear into which it is to be inserted. The lower surface also has an outer contour conforming to that of the footwear. However, the lower surface is not flat, but configured to provide one or more raised (three-dimensional) regions. It is the raised regions of the lower surface which in combination with the upper surface, form the internal cavities of the invented insole structure. In other structurally independent embodiments of the present invention the lower surface is flat while the upper surface provides one or more raised regions which, together with the lower surface, form the internal cavities. One application of the latter embodiment would be found in an insole structure configured to provide support to the arch of the foot.
The present invention also contemplates structurally independent embodiments which can be characterized as partial insoles; i.e., insoles configured to cushion and support only one portion of the wearers foot such as the heel, arch, or ball. Typically such partial insoles have a single fluid-filled cavity and an outer contour which conforms to the portion of the foot for which they are adapted.
Those embodiments of the present invention which are configured to fit within an item of conventional footwear must necessarily be relatively thin. A preferred overall thickness is about /8 inch; however, this constraint is not necessarily applicable in the vicinity of the arch of the foot.
With respect to embodiments of the present invention which are structurally part of the footwear, there are two which are preferred. The first is comprised of upper and lower surfaces of a flexible non-porous plastic, such as polyethylene, vinyl or elastomeric plastic, each surface being cemented and/or sewn into the structure of the item of footwear during the construction process. The two surfaces form one or more cavities with the body of the structure in which a suitable fluid is contained to provide the desired cushioning and support. In a second preferred embodiment of the type, the inner sole of the item of footwear is utilized as the lower surface of the invented insole structure. Accordingly, the inner sole has formed in its upper region one or more compartments which, in combination with the upper surface, form the fluid-containing cavitiesof the structure. The compartments are typically located so that the cushioning and support provided by the fluid is applied to one or more portions of the foot-as I porous material such as elastomeric plastic.
The users foot interfaces with the top of the upper surface of the structure. Consequently, in order to enhance the comfort of using the invented insole, preferred embodiments include a' moisture-absorbing fabric or other suitable covering secured to the top of the upper surface for the purpose of reducing the buildup ofa moisture during use.
The fluid which is encapsulated in the cavities within the body of the structure is a suitable non-compressible fluid such as water, air or a gel. The viscosity of the fluid is a variable, the selection of which enables the designers to achieve a range of effects relative to the feel of the insole. The cavities are typically filled with the fluid up to the ambient barometric pressure; i.e., without causing any stretching of the flexible plastic material comprising the surfaces of the structure. Stretching of this material does occur, however, when the users weight is applied to the insole, since there must be a redistribution of the fluid within the cavities.
in some applications, such as where support of the arch is sought, increased firmness may be required at a particular area of the insole structure. To achieve greater firmness, the fluid in a particular cavity can be maintained at a no-load pressure which is greater than the ambient air pressure. As a result, the elastic material comprising the structural surfaces will be stretched somewhat, even under no-load conditions. When the users weight is applied to the insole, there will be less elasticity and, consequently, greater firmness.
It can be seen therefore, that by selecting the viscosity of the fluid, the pressure of the fluid in the cavities, and the elasticity of the material comprising the'surfaces of the structure, the designer can achieve a broad range of support and cushioning effects in practicing this invention. In addition, the shape, contour, location and height of the cavities are variables which, by appropriate selection, enable a wide range of design objectives to be achieved.
Embodiments'of the present invention can be made by plastic forming and footwear construction techniques which are known in the art. Plastic forming techniques suitable for making the flexible plastic surfaces of the invented insole structure include injection molding, vacuum molding and blow molding processes.
polyethylene vinyl or Insertion of the fluid into the cavities can be accomcomfortably cushions and supports the users feet when wearing footwear.
It is still another object of the present invention to provide an insole structure which can be configured to have a therapeutic effect upon the feet of the user.
It. is still yet another object of the present invention to provide a structure which is adapted for insertion into conventional footwear.
A further object, of this invention is to provide a structure which is built into and made an integral part of footwear.
Other objects novel features and advantages of the present invention will become apparentupon making reference to the following detailed description and the accompanying drawings. The description and the drawings will also further disclose the characteristics of this invention, both as to its structure and its mode of operation. Although preferred embodiments of the invention are described hereinbelow, and shown in the accompanying drawing, it is expressly understood that the descriptions and drawings thereof are for the purpose of illustration only and do not'limit the scope of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings in which are illustrated preferred embodiments of the present invention:
FIG. 1 is a top perspective view of a flrst'embodiment of the present invention, showing an insole which is configured to be inserted into conventional footwear.
FIG. 2 is a cross-sectional view of the insole structure of FIG. 1 taken along lines 22 of FIG. 1.
FIG. 3 is a cross-sectional view of the insole structure of FIG. 1 taken along lines 33 of FIG. 1.
FIG. 4 is a longitudinal cross-sectional view of another embodiment of the present invention, showing a therapeutic shoe adapted to support the wearers arches.
FIG. 5 is a transverse cross-sectional view of the shoe of FIG. 4 taken along lines 5-5 of FIG. 4.
FIG. 6 is a longitudinal cross-sectional view of still another embodiment of the present invention, showing a shoe having fluid filled compartments in its inner sole.
FIG. 7 is a top perspective view of a further embodiment of the present invention showing a single cavity insole partial insole adapted to cushion and support the ball of the foot.
FIG. 8 is a top perspective view of another embodiment of the present invention showing a single cavity partial insole adapted to cushion and support the arch of the foot.
FIG. 9 is a top perspective view of a further embodiment of the present invention showing a single cavity insole partial insole adapted to cushion and support the heel of the foot.
DESCRIPTION OF THE PREFERRED EMBODIMENTS materials. However, it should be understood that the present invention also contemplates embodiments wherein the upper and lower surfaces 10 and 12 comprise a continuous and integral structure. The upper surface 10 and the lower surface 12 have outer contours which comform to the contour and style of the footwear into which embodiment 8 is to be inserted during use. Upper surface 10 is a flat piece of material, while lower surface 12 has raised contoured regions 12a, 12b, 12c and 12d. When joined together surfaces 10 and 12 form cavities 14a 14d in which a suitable non-compressible fluid 14' is contained (FIG. 2). Thus,
' tions and of different shapes and contours. In addition,
this invention also contemplates embodiments having a flat lower surface and a raised upper surface, the reverse of embodiment 8, as well as embodiments whose upper and lower surfaces each have raised regions. An embodiment of the latter type is depicted in FIG. 4 and described more fully hereinbelow.
A suitable moisture-absorbing fabric covering 16,.
preferably cotton, is disposed over the entire top of upper surface 10. Thus, during use, the users feet come into contact with covering 16 instead of the plastic material comprising upper surface 10. Covering 16 absorbs the moisture normally generated in footwear and thereby, enhances the comfort to be derived from use of the invented insole. Covering 16 may be cemented to the top surface of section 10 or joined by other suitable techniques known in the art. FIGS. 2 and 3 depict the covering 16 cooperatively engaged by a lip 18 extending around the periphery of upper surface 1 0 and is similar to that described in applicants US. Pat. No. 3,599,353 issued on Aug. 17, 1971. Lip 18 is an integral part of upper surface 10 and provides additional means for securing the covering 16 to the top of surface 10. Lip 18 will also prevent the edge of covering 16 from fraying or otherwise becoming disengaged. The extent to which the covering 16 is secured by the lip 18 is best seen by reference to FIGS. 2 and 3. The
. preferred length of lip 18, that is, the extent to which it overlaps covering 16, is about 1/32 inch. Although covering 16 can be any suitable moisture-absorbing fabric, it is preferable that .the fabric have a backing of flexible plastic on the side interfacing with the top of upper surface 10. Such backing would enhance the adhesion of covering 16 to surface 10.
Walls 13a, 13b, 13c,-and 13d of raised regions 12a 12d respectively are configured at an angle, with reference to the vertical, which ensures that they collapse under the weight of the wearers feet; i.e., by configuring the walls 13a 13d at such an angle, they are prevented from providing their own rigid structural support. As the angle of the walls 13a 13d approaches the vertical, the walls 13a 13d tend to act increasingly as rigid support members. At the proper angle, typically in the region of 45, the walls smoothly give way under the users weight and enable the insole support to be provided by the fluid 14'.
Since embodiment 8 is adapted for insertion into conventional footwear, an overall thickness of about I/18 of an inch is preferred.
The fluid 14 can be water or other appropriate liquid, air or a gel having a suitable viscosity. The fluid 14 is the cushioning and supporting medium of the inventedinsole. When the weight of the users foot is applied to the upper section 10, fluid 14' in the cavities 14a-14 immediately redistributes itself therein until .the upper surface 10 conforms to the contour of the bottom surface of the users foot whenever these surfaces are in contact. In addition, since it is a property of fluids to distribute applied pressure uniformily throughout the fluid, uniform support is applied to the users foot over its contacting surfaces. As a result the users weight is supported uniformly over a greater area of his feet than is the case with non-fluid supporting means. Thus, a firm, but pleasantly cushioned sensation of comfort is achieved while wearing footwear.
The viscosity of fluid 14' and the elasticity of the plastic material comprising surfaces 10 and 12 determine to a great extent the feel of the invented insole; in addition, the no-load pressure at which fluid 14' is maintained in cavities 14a 14d is a variable which has an effect upon the firmness, and therefore the feel, of the insole. As the no-load pressure of fluid 14' increases above the ambient atmospheric pressure, the flexible plastic material comprising surfaces 10 and 12 is stretched. To the extent there is such non-load stretching, there is a corresponding decrease in the ability of the material to stretch further when the users weight is applied to the insole. Consequently, the users weight is supported at a higher pressure applied over a smaller area of his feet, resulting in a firmer feeling of support. In some applications in which this invention may be practiced, greater firmness at a particular portion of the insole is desirable, such as where the insole is used to support the users arches. Such an application is more fully described hereinbelow with respect to a second embodiment of the invention.
The benefits of the present invention are not limited to enhancing the comfort of conventional footwear. The invention can be practiced so as to provide a therapeutic benefit for certain foot problems. For example, consider a user who has a sensitive area on the sole of his foot due to a callous or a cut. Since the present invention is better adapted than conventional insoles to uniformly distribute the applied pressure over a larger area of the foot, there is an immediate benefit to such a user by virtue of the fact that less pressure is applied to the sensitive area. In addition, an embodiment of the present invention can be designed which even further reduces the pressure applied to the sensitive area. For example, by providing a donutshaped raised region on the upper surface of the insole structure, a region coming into contact only with the area of the user's sole surrounding the sensitive area, the pressure on the sensitive area can be reduced substantially.
Another therapeutic application of the present invention relates to the support of weak arches. With reference to FIGS. 4 and 5, a second embodiment, a therapeutic shoe 30 configured for use by persons with weak arches, is described. In this embodiment the insolestructure is an integral part of the shoe 30 and is incorporated therein during the process of shoe construction. The insole structure is comprised of an upper surface 32, having a raised contoured region 32c in the vicinity of the arch, and a lower surface 34 having raised regions 34a, 34b, and 34d. Surface 34 is disposed upon the inner sole 35 and is secured thereto, as well as to thestructure of shoe 30, by conventional techniques knownjn the art. Surfaces 32 and 34 are made of a flexible plastic material such as those disclosed hereinabove. When joined, they form cavities 36a 36d which contain a fluid 36 in the same manner as described above with reference to the embodiment shown in FIG. 2. Of particular interest in this, second embodiment 30 is the raised region 32c of surface 32 which forms cavity 360. It is shaped to conform to the normal contour of the arch of a human foot and is located with respect thereto. The fluid 36' in cavity 36c is preferably one having a high viscosity. The no-load pressure of fluid 36' in cavity 360 and the elasticity of the plastic material comprising surface 32 can be selected by those skilled in the art so that the insole structure in the vicinity of the users arch provides firm support thereto.
A moisture-absorbing covering 38 is preferably disposed upon the top of surface 32 and secured thereto, as well as to the structure of shoe 30 by means known in the art.
The manner in which the insole structure of this second embodiment 30 provides cushioning and support to the users feet is the same as that described above with respect to the first embodiment. As is the case with respect to the first preferred embodiment described hereinabove, walls 37a, 37b and 37d of raised regions 34a, 34b and 34d are at an angle with respect to the vertical, typically 45, which ensures that they smoothly give way under the users weight and thereby not provide their own rigid structural support.
A third preferred embodiment, of the present invention is shown in FIG. 6, the insole being disposed within shoe structure 40. In this embodiment, as in the second embodiment, the present invention insole structure is an integral part of the shoe 40 and is incorporated therein during the process of manufacturing the shoe 40.
An inner sole 42 of the shoe 40 is utilized to provide the lower surface of the insole structure. Compartments 44a 44d are configured in the upper region of the inner sole 42 to a depth of about A; of an inch. The area, shape and location of the compartments 44a 44d are selected to provide cushioning and support to particular portions of its foot. In this preferred embodiment of the present invention 40, four compartments are depicted so that cushioned support is provided to the toes, ball, instep and heel respectively. An upper surface 46 is disposed over the inner sole 42 and secured thereto, as well as to the structure of shoe 40, by methods known in the art. Surface 46 is made of a flexible plastic material, preferably of one of the kinds described above. The joining of surface 48 to inner sole 42 seals the compartments 44a 44d which become the internal fluid 44' filled cavities characteristic of the invented insole structure. The manner in which the above described structure provides cushioned support to the user s feet is the same as has been described with respect to the first embodiment.
A moisture-absorbing covering 48 is preferably disposed upon the top of surface 46 and secured thereto, as well as to the structure of the shoe 40.
An additional feature which is preferable in the embodiments of the present invention is the presence of air holes or channels in the insole structure at locations which do not effect the structure's capability to contain the fluid in the cavities therein. The purpose of such air holes or channels is to enable the circulation of air within the item of footwear; i.e., to enhance the ventilation of its inner regions.
The present invention also contemplates embodiments, structurally independent of the footwear, which can be characterized as partial insoles; i.e., insoles configured to cushion and support only one portion of the users foot. These partial insoles are inserted into the item of footwear at the locations at which they are adapted for use. With reference to FIGS. 7-9 those preferred forms of the partial insole embodiments of this invention are shown. In FIG. 7 insole 50, adapted to support and cushion the ball of the foot, is shown. It has a single fluid-filled cavity formed, as in the other embodiments, by upper and lower surfaces, the lower surface having a single raised region 52 with sloping walls 54. In FIG. 8 an insole 60, adapted to support and cushion the arch of the foot, is shown. It too has a single fluid-filled cavity similar in construction to that of insole 50. FIG. 9 depicts a similar single cavity insole 70 adapted to support and cushion the heel. These three embodiments also contemplate the addition of a moisture-absorbing fabric, secured to the top of the upper surface, to enhance the users comfort by reducing the build-up of excess moisture.
The plastic surfaces which comprise the invented insole structure can be produced by conventional plastic forming techniques such as injection molding, vacuum molding or blow molding. When either injection molding or vacuum molding processes are utilized, the
upper and lower surfaces are typically separate elements and must be joined together with leakproof bond. This can be accomplished by methods and materials known in the art. The fluid which is encapsulated in the cavities formed within the body of the insole structure can be encapsulated during the process of joining the upper and lower section of the structure, or afterwards, by known fluid injection and sealing techniques.
With reference to FIGS. l-3, a fabric covering 16 p was described, secured to the top of upper surface 10 hereabove. Prior to injecting the plastic material into the mold, the covering 16 is inserted into the mold, the outer edge of which extends approximately 1/32 of an inch into the area that will be permeated with the injected plastic. Thus, when the plastic material is injected, the lip 18- will form around the outer edge of the covering 16, thereby securing it to the top of the upper surface 10.
The insole structure which is structurally independent of the item of footwear, i.e., the first preferred embodiment disclosed above, lends itself to production by the techniques of blow molding. By this method, an integral-structure is formed. This has the advantage of eliminating the steps'of bonding separate upper and lower surfaces; and further, it eliminates the risk of fluid leakage due to defective bonding. Blow molding an insole adapted for insertion-into footwear, of course, is done while the plastic material is in a semi-molten state. After the structure is molded, and while the plastic is still semi-molten, the, upper and lower surfaces are joined in the areas between the raised regions by the application of heat and pressure. In this manner separate sealed internal cavities are formed. The fluid is injected into the cavities by means of an appropriate injection apparatus, after which the hole caused during injection is heat sealed.
Other embodiments, modifications and extensions of this invention will become apparent to those skilled in the art. All such variations which basically rely on the teachings which this invention has advanced are considered within the spirit and scope of this invention.
1. An insole adapted for insertion into a conventional article of footwear comprising:
a. a single integral structure having an upper and a lower surface, said lower surface having at least one raised region defining an internal cavity between said upper and lower surfaces, said raised region depending downwardly and having side walls lying at an angle of approximately 45 with reference to the vertical, said structure being fabricated of a flexible non-porous plastic selected from a group consisting of polyethylene, vinyl and elastomeric plastic and having an overall thickness of approximately 4; inch;
. water disposed within said cavity and encapsulated therein at ambient atmospheric pressure in a noload condition; and
c. a moisture-absorbing fabric disposed upon and fixedly secured to the top side of said upper surface, said fabric having a backing of flexible plastic on its side which is in contact with said upper surface, whereby, when said insole is inserted into said article of footwear, it provides cushioning and support to the foot of a wearer of said article, and said fabric absorbs moisture inside said article.
2. The insole of claim 1 wherein said structure has a plurality of perforations located in portions thereof displaced from said internal cavity, said perforations being adapted to enable the circulation of air through said structure.
3. In an article of footwear, and integral thereto, an insole comprising:
a. a structure having an upper and a lower surface, said upper surface having a first raised region defining a first internal cavity between said upper and lower surfaces, said first raised region being located and contoured upwardly to cooperatively engage the arch of a human foot, said lower surface having at least one raised region defining a second internal cavity between said surfaces, said latter raised region depending downwardly and being displaced from said first raised region in the longitudinal direction of said structure, said structure being fabricated of a. flexible non-porous plastic selected from a group consisting of polyethylene, vinyl and elastomeric plastic; fluid of suitable viscosity disposed within said first and second cavities and encapsulated therein, the pressure of said fluid in said first cavity being sufficient to provide firm support to said arch, the pressure of said fluid in said second cavity, being ambient atmospheric pressure in a no-load condition; and
c. a moisture-absorbing fabric disposed upon and fixcontain water therein;
edly secured to the top side of said upper surface, whereby said insole provides cushioning and support to the foot of a wearer of said article of footwear, and said fabric absorbs moisture inside said article.
. a thin, substantially flat upper member made of a flexible non-porous plastic selected from a group consisting of polyethylene, vinyl and elastomeric plastic, said upper member being disposed over and fixedly secured to said inner sole so as to seal 4. In an article of footwear having an inner sole, an insole providing cushioning and support to the foot of a wearer comprising:
a. a plurality of suitably contoured cavities formed in said cavities; c. a moisture-absorbing fabric disposed upon and fixedly secured to the top side of said upper member;
the upper region of said inner sole to a depth of approximately /8 inch, said cavities being separated from one another by ribbed members disposed thereinbetween, said cavities being adapted to and lated therein.
' UNITED STATES PATENT OFFICE l CERTIFICATE OF CQRRECTION Inventor) Herbert Magidson It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
Column 6, line 68, "section" should read surface Column 8, line 45, delete the word "its" and substitute the wearer's Column 8, line 55 delete the numerical design ation +8" and substitute thedesignation A6 Signed and sealed this 3rd day of December 1974.
MCCOY M. GIBSON JR. I C. MARSHALL DANN Attesting Officer Commissioner of Patents USCOMM-DC 60376-P69 us. sovznnmin l PRINTING OFFICE l9! 0-366-334.
FORM PO-105O (10-69)