Information
-
Patent Grant
-
6301805
-
Patent Number
6,301,805
-
Date Filed
Monday, July 31, 200024 years ago
-
Date Issued
Tuesday, October 16, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 036 37
- 036 28
- 036 43
- 036 44
- 036 91
- 036 92
- 036 88
- 036 145
- 036 166
- 036 173
- 036 178
- 036 181
-
International Classifications
-
Abstract
A removable insole for insertion into footwear, includes a forefoot portion extending at least to metatarsals of a foot, with a second recess at an undersurface thereof with a plurality of cylindrical protuberances in the recess; a cupped heel portion including a relatively flat central portion and a sloped side wall surrounding the relatively flat central portion; a mid-foot portion connecting together the forefoot portion and the heel portion, the mid-foot portion including a medial arch portion defined by an extension of the sloped side wall, the sloped side wall extends to lateral and medial sides of the mid-foot portion, and the forefoot portion, heel portion and mid-foot portion formed from a unitary resilient material; a shell that extends along an underside of the insole, the medial arch portion and the sloped side wall at the heel portion and the mid-foot portion, the shell having an opening beneath the relatively flat central portion of the cupped heel portion and a gap at a rearmost end of the shell so as to define flanges on opposite sides of the insole at the heel portion, the unitary resilient material extending out through the opening in the shell, and includes a recess at an undersurface thereat with a plurality of cylindrical protuberances in the recess, and the shell being made of a flexible material that is stiffer than the unitary resilient material; and a top cover secured to upper surfaces of the forefoot portion, mid-foot portion and heel portion.
Description
BACKGROUND OF THE INVENTION
The present invention relates generally to shoe insoles, and more particularly, to improved insoles particularly adapted for obese people.
According to an article “Demography, Obesity: A Growing Problem, ” The Futurist, October, 1999, approximately 22% of adults in the United States are obese, with obesity defined by the World Health Organization as a body mass index greater than or equal to 30 Kg/m
2
.
The inventors herein designed and executed an investigative gait and foot morphology study to define the gait biomechanics and foot morphology of obese men and women. It was discovered that obese people exerted more load under the arch and lateral side of their feet during gait in comparison with individuals having a body mass index less than or equal to 25 kg/m
2
. Approximately 36% of the obese women subjects provided varying degrees of pes planus (flat feet), while approximately 43% of the obese men subjects provided varying degrees of pes planus (flat feet). Further, the frequency of moderate fatigue or discomfort in the foot, leg and lower back exceeded 50% in the male and female population. Still further, overall gait speed tended to be slower than that for that part of the population having a normal weight, that is, a body mass index less than or equal to 25 kg/m
2
.
From this study, it was determined that:
a) obese people have wider feet and put more pressure on the mid-foot and forefoot portions;
b) obese people overpronate, tending to flatten or fall on the inside arch of the foot;
c) obese people have a tendency to walk with their feet wider apart, and this, in combination with the overpronation (flat feet), prevents normal foot motion during walking; and
d) obese people tend to roll their feet outward during heel strike, thereby introducing an extraneous motion to the foot, in contrast to normal weight people who do not roll their feet during heel strike. This increases the loading in the lateral arch region during gait.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an insole that overcomes the aforementioned problems.
It is another object of the present invention to provide an insole for obese people.
It is still another object of the present invention to provide an insole which reduces lower extremity, back and foot pain for obese people.
It is yet another object of the present invention to provide an insole which cushions the total foot contact area from heel strike through mid-foot stance, and during toe off (propulsion) for obese people.
It is a further object of the present invention to provide an insole which provides additional flexibility and cushioning for obese people.
It is a still further object of the present invention to provide an insole which provides control and substantial reduction of overpronation for obese people.
It is a yet further object of the present invention to provide an insole that provides a comprehensive arch and mid-foot support for obese people.
It is another object of the present invention to provide an insole that provides lateral foot support for obese people.
It is still another object of the present invention to provide an insole that will accommodate multiple heel sizes for obese people.
It is yet another object of the present invention to provide an insole that positions the fat pad under the calcaneus for obese people.
It is a further object of the present invention to provide an insole that is easy and economical to make and use.
In accordance with an aspect of the present invention, a removable insole for insertion into footwear, includes a forefoot portion extending at least to metatarsals of a foot; a cupped heel portion including a relatively flat central portion and a sloped side wall surrounding the relatively flat central portion; a mid-foot portion connecting together the forefoot portion and the heel portion, the mid-foot portion including a medial arch portion defined by an extension of the sloped side wall, and the forefoot portion, heel portion and mid-foot portion formed from a unitary resilient material; and a shell that extends along an underside of the insole, the shell extending under the medial arch portion and the side wall, the shell having an opening beneath the relatively flat central portion of the cupped heel portion and a gap at a rearmost end of the shell so as to define flanges on opposite sides of the insole at the heel portion, and the shell being made of a flexible material that is stiffer than the unitary resilient material.
The sloped side wall extends to lateral and medial sides of the mid-foot portion, and the shell extends along an underside of the sloped side wall at the heel portion and the mid-foot portion.
The unitary resilient material extends out through the opening in the shell, and includes a recess at an undersurface thereat with a plurality of first protuberances in the recess, the first protuberances forming spaced apart spring walls and the first protuberances having lower edges generally coplanar with a lower surface of the heel portion. Preferably, the first protuberances have a generally cylindrical configuration. Also, the unitary resilient material includes a second recess at an undersurface thereof at the forefoot portion, with a plurality of second protuberances in the second recess, the second protuberances forming spaced apart spring walls and the second protuberances having lower edges generally coplanar with a lower surface of the heel portion. Preferably, the second protuberances have a generally cylindrical configuration. The first and second protuberances have a height and width, and the height of the second protuberances is less than the height of the first protuberances, and the width of the second protuberances is greater than the width of the first protuberances.
A top cover is secured to upper surfaces of the forefoot portion, mid-foot portion and heel portion.
Also, at least one pattern trim line is formed at the forefoot portion for trimming the insole to fit into smaller size footwear.
Lastly, the medial arch portion has a height greater than a remainder of the mid-foot portion, and extends approximately 40% of the distance from a medial side of the insole to a lateral side of the insole.
In accordance with another aspect of the present invention, footwear includes an outer sole; an inner sole connected to the outer sole, the inner sole including a forefoot portion extending at least to metatarsals of a foot, a cupped heel portion including a relatively flat central portion and a sloped side wall surrounding the relatively flat central portion, a mid-foot portion connecting together the forefoot portion and the heel portion, the mid-foot portion including a medial arch portion defined by an extension of the sloped side wall, and the forefoot portion, heel portion and mid-foot portion formed from a unitary resilient material, and a shell that extends along an underside of the insole, the shell extending under the medial arch portion and the side wall, the shell having an opening beneath the relatively flat central portion of the cupped heel portion and a gap at a rearmost end of the shell so as to define flanges on opposite sides of the insole at the heel portion, and the shell being made of a flexible material that is stiffer than the unitary resilient material; and an upper connected to at least one of the outer sole and the inner sole.
The above and other features of the invention will become readily apparent from the following detailed description thereof which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a bottom perspective view of a left insole according to the present invention;
FIG. 2
is a bottom plan view of the left insole;
FIG. 3
is a top plan view of the left insole;
FIG. 4
is a side elevational view of the left insole;
FIG. 5
is a front elevational view of the left insole;
FIG. 6
is a cross-sectional view of the left insole, of substantially actual size, taken along line
6
—
6
of
FIG. 3
;
FIG. 7
is a cross-sectional view of the left insole, of substantially actual size, taken along line
7
—
7
of
FIG. 3
; and
FIG. 8
is a cross-sectional view of the left insole, of substantially actual size, taken along line
8
—
8
of FIG.
3
.
DETAILED DESCRIPTION
Referring to the drawings in detail, a left insole
10
according to a first embodiment of the present invention is adapted to be placed in an article of footwear, as is well known. A right insole (not shown) is identical to left insole
10
and is a mirror image thereof. Insole
10
is particularly adapted to alleviate back, hip, leg and foot pain in obese people.
Insole
10
has the shape of a human left foot and therefore includes a curved toe or forefoot portion
12
, a heel portion
14
, and a mid-foot portion
16
which connects forefoot portion
12
and heel portion
14
together. Heel portion
14
has a greater thickness than forefoot portion
12
. For example, heel portion
14
may have a thickness in the range of about 0.16 inch to 0.25 inch for men's insoles and in the range of about 0.16 inch to 0.24 inch for women's insoles, while forefoot portion
12
may have a thickness in the range of about 0.12 inch to 0.22 inch for men's insoles and in the range of about 0.12 inch to 0.20 inch for women's insoles.
Insole
10
is formed by a lower cushioning layer
18
and a top cover
20
secured to the upper surface of cushioning layer
18
, along forefoot portion
12
, cupped heel portion
14
and mid-foot portion
16
, by any suitable means, such as adhesive, RF welding, etc.
Cushioning layer
18
can be made from any suitable material including, but not limited to, any flexible material which can cushion and absorb the shock from heel strike on the insole. Suitable shock absorbing materials can include any suitable foam, such as but not limited to, cross-linked polyethylene, poly(ethylene-vinyl acetate), polyvinyl chloride, synthetic and natural latex rubbers, neoprene, block polymer elastomer of the acrylonitrile-butadiene-styrene or styrene-butadienestyrene type, thermoplastic elastomers, ethylenepropylene rubbers, silicone elastomers, polystyrene, polyurea or polyurethane; most preferably a polyurethane foam made from flexible polyol chain and an isocyanate such as a monomeric or prepolymerized diisocyanate based on 4,4′-diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI). Such foams can be blown with freon, water, methylene chloride or other gas producing agents, as well as by mechanically frothing to prepare the shock absorbing resilient layer. Such foams advantageously can be molded into the desired shape or geometry. Non-foam elastomers such as the class of materials known as viscoelastic polymers, or silicone gels, which show high levels of damping when tested by dynamic mechanical analysis performed in the range of −50 degrees C. to 100 degrees C. may also be advantageously employed. A resilient polyurethane can be prepared from diisocyanate prepolymer, polyol, catalyst and stabilizers which provide a waterblown polyurethane foam of the desired physical attributes. Suitable diisocyanate prepolymer and polyol components include polymeric MDI M-10 (CAS 9016-87-9) and Polymeric MDI MM-103 (CAS 25686-28-6), both available from BASF, Parsippany, N.J.; Pluracol 945 (CAS 9082-00-2) and Pluracol 1003, both available from BASF, Parsippany, N.J.; Multrinol 9200, available from Mobay, Pittsburgh, Pa.; MDI diisocyanate prepolymer XAS 10971.02 and polyol blend XUS 18021.00 available from the Dow Chemical Company, Midland, Mich.; and Niax 34-28, available from Union Carbide, Danbury, Conn. These urethane systems generally contain a surfactant, a blowing agent, and an ultra-violet stabilizer and/or catalyst package. Suitable catalysts include Dabco 33-LV (CAS 280-57-9,2526-71-8), Dabco X543 (CAS Trade Secret), Dabco T-12 (CAS 77-58-7), and Dabco TAC (CAS 107-21-1) all obtainable from Air Products Inc., Allentown, Pa.; Fomrez UL-38, a stannous octoate, from the Witco Chemical Co., New York, N.Y. or A-1(CAS 3033-62-3) available from OSI Corp., Norcross, Ga. Suitable stabilizers include Tinuvin 765 (CAS 41556-26-7), Tinuvin 328 (CAS 25973-55-1), Tinuvin 213 (CAS 104810-48-2), Irganox 1010 (CAS 6683-19-8), Irganox 245 (CAS 36443-68-2), all available from the Ciba Geigy Corporation, Greensboro, N.C., or Givsorb UV-1 (CAS 057834-33-0) and Givsorb UV-2 (CAS 065816-20-8) from Givaudan Corporation, Clifton, N.J. Suitable surfactants include DC-5169 (a mixture), DC190 (CAS68037-64-9), DC197 (CAS69430-39-3), DC-5125 (CAS 68037-62-7) all available from Air Products Corp., Allentown Pa. and L-5302 (CAS trade secret) from Union Carbide, Danbury Conn. Alternatively, lower layer
18
can be a laminate construction, that is, a multilayered composite of any of the above materials. Multilayered composites are made from one or more of the above materials such as a combination of polyethylene vinyl acetate and polyethylene (two layers), a combination of polyurethane and polyvinyl chloride (two layers) or a combination of ethylene propylene rubber, polyurethane foam and ethylene vinyl acetate (3 layers). Preferably, cushioning layer
18
is made from a urethane molded material.
The materials of lower layer
18
can be prepared by conventional methods such as heat sealing, ultrasonic sealing, radio-frequency sealing, lamination, thermoforming, reaction injection molding, and compression molding and, if necessary, followed by secondary die-cutting or in-mold die cutting. Representative methods are taught, for example, in U.S. Pat. Nos. 3,489,594; 3,530,489 4,257,176; 4,185,402; 4,586,273, in the Handbook of Plastics, Herber R. Simonds and Carleton Ellis, 1943, New York, N.Y., Reaction Injection Molding Machinery and Processes, F. Melvin Sweeney, 1987, New York, N.Y., and Flexible Polyurethane Foams, George Woods, 1982, New Jersey, whose preparative teachings are incorporated herein by reference. For example, the innersole can be prepared by a foam reaction molding process such as taught in U.S. Pat. No. 4,694,589.
Top cover
20
can be made from any suitable material including, but not limited to, fabrics, leather, leatherboard, expanded vinyl foam, flocked vinyl film, coagulated polyurethane, latex foam on scrim, supported polyurethane foam, laminated polyurethane film or in-mold coatings such as polyurethanes, styrene-butadiene-rubber, acrylonitrile-butadiene, acrylonitrile terpolymers and copolymers, vinyls, or other acrylics, as integral top covers. Desirable characteristics of top cover
20
include good durability, stability and visual appearance. It is also desirable that top cover
20
have good flexibility, as indicated by a low modulus, in order to be easily moldable. The bonding surface of top cover
20
should provide an appropriate texture in order to achieve a suitable mechanical bond to the upper surface of lower layer
18
. Preferably, the material of top cover
20
is a fabric, such as a brushed knit laminate top cloth (brushed knit fabric/urethane film/non-woven scrim cloth laminate) or a urethane knit laminate top cloth. Preferably, top cover
20
is made from a polyester fabric material, and preferably has a thickness of about 0.02 inch.
During use, insole
10
is placed in a shoe so that the medial side
22
containing a raised medial arch portion
16
a
of mid-foot portion
16
rests against the inside of the shoe. Forefoot portion
12
may end just in front of the metatarsals. Insole
10
is a full length insole, that is, extends along the entire foot.
Typically, insole
10
would be sized corresponding to shoe sizes and would be provided in sized pairs. Alternatively, insole
10
may be trimmed to the requirements of the user. In this regard, arcuate pattern trim lines
24
a-
24
d
may be formed on the lower surface of forefoot portion
12
of insole
10
, as shown in
FIG. 1
, and which are representative of various sizes of the human foot. For example, insole
10
may be provided for a man's shoe size of
12
, with first continuous pattern trim line
24
a
being representative of a smaller size insole for a man's shoe size
11
, second continuous pattern trim line
24
b
extending around the periphery of forefoot portion
12
indicative of another size of insole for a man's shoe size
10
, third continuous pattern trim line
24
c
extending around the periphery of forefoot portion
12
indicative of another size of insole for a man's shoe size
9
, and fourth continuous pattern trim line
24
d
extending around the periphery of forefoot portion
12
indicative of another size of insole for a man's shoe size
8
. If the user requires a size other than the original large size, the wearer merely trims the insole with a scissors or cutting instrument, using pattern trim lines
24
a-
24
d,
to achieve the proper size. The pattern trim lines may be imprinted by conventional printing techniques, silkscreening and the like. As an alternative, pattern trim lines
24
a-
24
d
may be formed as shallow grooves, or be perforated, so that a smaller size insole may be separated by tearing along the appropriate trim lines, which tearing operation is facilitated by the inclusion of perforations. Thus, forefoot portion
12
can be trimmed so that forefoot portion
12
fits within the toe portion of a shoe.
A cup-shaped arrangement is also provided for the heel and mid-foot in order to stabilize the mid-foot and heel, while at the same time, providing overall cushioning and shock absorption of the mid-foot and heel. This is because there are joints in the mid-foot area and heel. If the foot is not stabilized, that is, without undue side to side movement, there may be pain due to the excessive joint forces.
Specifically, as shown, heel portion
14
includes a relatively flat central portion
14
a,
and a sloped side wall
14
b.
Generally, when a heel strikes a surface, the fat pad portion of the heel spreads out. The cupped heel portion thereby stabilizes the heel of the person and maintains the heel in heel portion
14
, to prevent such spreading out of the fat pad portion of the heel, and to also prevent any side to side movement of the heel in heel portion
14
.
The side wall
14
b
of heel portion
14
extends forwardly to the mid-foot as a flange or side wall
16
b
on the lateral and medial sides of mid-foot portion
16
, with side wall
16
b
extending to a further extent forwardly at the medial side
22
to correspond to the medial arch portion
16
a
thereat. According to the present invention, raised arch portion
16
a
extends from the medial side
22
toward the lateral side
23
of insole
10
by a greater amount than conventional insoles, for example, 40% toward lateral side
23
. This results in a counteraction to the overpronation that normally occurs in obese people, that is, this increased arch support functions to prevent overpronation. It will also be appreciated that side wall
16
b
thereby starts at heel portion
14
and extends at least to a midpoint of insole
10
, to provide a foot cradle.
In accordance with the present invention, insole
10
is made wider than normal insoles, for example, an extra 0.25 inch wider to accommodate the wider feet of obese people. Further, forefoot portion
12
is provided with a thickness greater than conventional insoles in order to accommodate the greater pressure thereon.
More importantly, a thin shell
26
of about 0.04 inch (1 mm) thickness is provided on the underside of insole
10
. Shell
26
is made of a more rigid or stiffer material than lower cushioning layer
18
and provides extra support. Thus, while lower cushioning layer
18
is made from a resilient and deformable foam material, shell
26
is made from a flexible, stiffer thermoplastic polymer, elastic polymer, flexible thermoplastic material or the like, but is substantially not resilient. Shell
26
can be made of any flexible material including but not limited to injection molded thermoplastic elastomers such as thermoplastic urethane, thermoplastic polyethylene or other injection molded polymers, and polymers that can be thermoformed such as ethylene vinyl acetate (EVA) or nylons.
Shell
26
aids in defining a more substantial raised arch portion
16
a
so as to counter the overpronation that occurs with obese people. In this regard, shell
26
extends up side walls
14
b
and
16
b
to provide extra support. Further, shell
26
further supports raised arch portion
16
a
which extends to a further extent toward lateral side
23
of insole
10
by a greater amount than conventional insoles. Also, shell
26
further supports the heel cradle which provides extra support, that is, by extending up side wall
14
b
of heel portion
14
.
However, shell
26
does not extend along the entire heel portion
14
. Specifically, as shown best in
FIGS. 1
,
2
and
8
, shell
26
includes a substantially oval opening
28
at the center of heel portion
14
corresponding to the fat pad of the person striking heel portion
14
during a normal gait, and there is a gap
30
at the rear end of heel portion
14
in open communication with opening
28
. As a result, shell
26
forms two rear heel flanges
26
a
and
26
b
on opposite sides of opening
28
. Because of this construction, expansion of heel portion
14
is permitted when an obese person steps onto insole
10
. Specifically, this permits expansion of heel portion
14
to accommodate different size heels. This is because the heel of an obese person is wider than conventional heels, and tends to flatten out. By providing flanges
26
a
and
26
b,
the heel of the person is still supported in a cup-like manner, but a slight expansion of heel portion
14
is still permitted.
As discussed above, obese person, when walking, tend to roll outward during the heel strike, thereby providing an extraneous motion to the heel strike, in contrast to normal weight people who start rolling outward at the midpoint of the foot, that is, at a much later stage. This outward roll continues from the heel through the entire motion of the foot. Shell
26
functions to deter such roll out during the heel strike, thereby forcing the person to roll forward rather than sidewards. This is due to the stiffer material of shell
26
used therewith.
Another reason for providing oval opening
28
is to provide equally spaced apart small protuberances
32
in an oval recess
34
on the underside of heel portion
14
.
Preferably, protuberances
32
have a cylindrical configuration of approximately 0.16 inch diameter and a height of about 0.06 inch, although the present invention is not limited thereby. For example, protuberances
32
can have other dimensions and other configurations such as square, triangular or polygonal cross-sectional columnar shapes, or other shapes, such as spaced apart sinusoidal walls or the like. The lower ends of protuberances
32
are substantially coplanar with the lower surface of insole
10
. Protuberances
32
effectively form spaced apart, elastic, resilient spring walls.
In like manner, a recess
36
is provided on the underside of forefoot portion
12
, and includes a plurality of equally spaced apart protuberances
38
therein. Recess
36
occupies a substantial central area of toe portion
12
. Preferably, protuberances
38
also have a cylindrical configuration of approximately 0.30 inch diameter and a height of about 0.03 inch, although the present invention is not limited thereby. For example, protuberances
38
can have other dimensions and other configurations such as square, triangular or polygonal cross-sectional columnar shapes, or other shapes, such as spaced apart sinusoidal walls or the like. The lower ends of protuberances
38
are substantially coplanar with the lower surface of insole
10
.
The reason for providing protuberances
32
and
38
in recesses
34
and
36
of heel portion
14
and forefoot portion
12
, respectively, is that these are the areas where the major forces are exerted on insole
10
during heel impact and during push off. With this arrangement, protuberances
32
and
38
provide a quicker acting spring than the remainder of insole
10
, but with less dampening energy absorption. Thus, when a force is applied to protuberances
32
and
38
, the response is more like a spring than as a damper, while the remainder of lower cushioning layer
18
has an opposite response, that is, acting more like a damper than a spring. This combination gives insole
10
a unique feature of a fast reaction on first heel impact and a slower higher damped energy absorption as the heel recedes into insole
10
. When the heel recedes from insole
10
, the reverse action occurs, that is, protuberances
32
return some of the spring action to the heel. When the foot moves to push off, the action of insole
10
is the same. In other words, this combination gives insole
10
a unique feature of a fast reaction on first forefoot impact and a slower higher damped energy absorption as the forefoot recedes into the viscous base of insole
10
. When the forefoot recedes from insole
10
, the reverse action occurs, that is, protuberances
38
return some of the spring action to the forefoot, giving the foot a softer impact and a springy push off.
The reason for the different dimensions of protuberances
32
and
38
is due to the fact that the person applies the same force on forefoot portion
12
as on heel portion
14
, but stays over forefoot portion
12
for a longer period of time.
Protuberances
32
and
38
also function to absorb shear from any sidewards movement of the foot on insole
10
.
Although the present invention uses the term insole, it will be appreciated that the use of other equivalent or similar terms such as innersole or insert are considered to be synonymous and interchangeable, and thereby covered by the present claimed invention.
Further, although the present invention has been discussed in relation to a removable insole, it can be incorporated as a permanent inner sole in footwear, such as a shoe or the like.
Having described specific preferred embodiments of the invention with reference to the accompanying drawings, it will be appreciated that the present invention is not limited to those precise embodiments and that various changes and modifications can be effected therein by one of ordinary skill in the art without departing from the scope or spirit of the invention as defined by the appended claims.
Parts Designator
10
insole
12
forefoot portion
14
heel portion
14
a
flat central portion
14
b
sloped side wall
16
mid-foot portion
16
a
raised medial arch portion
16
b
side wall
18
lower cushioning layer
20
top cover
22
medial side
23
lateral side
24
a-d
pattern trim lines
26
thin shell
26
a
flange
26
b
flange
28
oval opening
30
gap
32
protuberances
34
oval recess
36
recess
38
protuberances
Claims
- 1. A removable insole for insertion into footwear, comprising:a forefoot portion extending at least to metatarsals of a foot; a cupped heel portion including a relatively flat central portion and a sloped side wall surrounding said relatively flat central portion; a mid-foot portion connecting together said forefoot portion and said heel portion, said mid-foot portion including a medial arch portion defined by an extension of said sloped side wall, and said forefoot portion, heel portion and mid-foot portion formed from a unitary resilient material; and a shell that extends along an underside of said insole, said shell extending under said medial arch portion and said side wall, said shell having an opening beneath said relatively flat central portion of said cupped heel portion and a gap at a rearmost end of said shell so as to define flanges on opposite sides of said insole at said heel portion, and said shell being made of a resilient material that is stiffer than said unitary resilient material, wherein said unitary resilient material extends out through said opening in said shell, and includes a recess at an undersurface thereat with a plurality of first protuberances in said recess, said first protuberances forming spaced apart spring walls and said first protuberances having lower edges generally coplanar with a lower surface of said heel portion.
- 2. A removable insole according to claim 1, wherein said first protuberances have a generally cylindrical configuration.
- 3. A removable insole according to claim 1, wherein said unitary resilient material includes a second recess at an undersurface thereof at said forefoot portion, with a plurality of second protuberances in said second recess, said second protuberances forming spaced apart spring walls and said second protuberances having lower edges generally coplanar with a lower surface of said heel portion.
- 4. A removable insole according to claim 3, wherein said second protuberances have a generally cylindrical configuration.
- 5. A removable insole according to claim 3, wherein said first and second protuberances have a height and width, and the height of said second protuberances is less than the height of said first protuberances, and the width of said second protuberances is greater than the width of said first protuberances.
- 6. A removable insole according to claim 1, further comprising a top cover secured to upper surfaces of said forefoot portion, mid-foot portion and heel portion.
- 7. A removable insole according to claim 1, further comprising at least one pattern trim line at the forefoot portion for trimming the insole to fit into smaller size footwear.
- 8. An insole according to claim 1, wherein said medial arch portion has a height greater than a remainder of said mid-foot portion, and extends approximately 40% of the distance from a medial side of said insole to a lateral side of said insole.
- 9. Footwear comprising:an outer sole; an inner sole connected to said outer sole, said inner sole including: a forefoot portion extending at least to metatarsals of a foot, a cupped heel portion including a relatively flat central portion and a sloped side wall surrounding said relatively flat central portion, a mid-foot portion connecting together said forefoot portion and said heel portion, said mid-foot portion including a medial arch portion defined by an extension of said sloped side wall, and said forefoot portion, heel portion and mid-foot portion formed from a unitary resilient material, and a shell that extends along an underside of said insole, said shell extending under said medial arch portion and said side wall, said shell having an opening beneath said relatively flat central portion of said cupped heel portion and a gap at a rearmost end of said shell so as to define flanges on opposite sides of said insole at said heel portion, and said shell being made of a resilient material that is stiffer than said unitary resilient material; and an upper connected to at least one of said outer sole and said inner sole, wherein said unitary resilient material extends out through said opening in said shell, and includes a recess at an undersurface thereat with a plurality of first protuberances in said recess, said first protuberances forming spaced apart spring walls and said first protuberances having lower edges generally coplanar with a lower surface of said heel portion.
- 10. Footwear according to claim 9, wherein said first protuberances have a generally cylindrical configuration.
- 11. Footwear according to claim 9, wherein said unitary resilient material includes a second recess at an undersurface thereof at said forefoot portion, with a plurality of second protuberances in said second recess, said second protuberances forming spaced apart spring walls and said second protuberances having lower edges generally coplanar with a lower surface of said heel portion.
- 12. Footwear according to claim 11, wherein said second protuberances have a generally cylindrical configuration.
- 13. Footwear according to claim 11, wherein said first and second protuberances have a height and width, and the height of said second protuberances is less than the height of said first protuberances, and the width of said second protuberances is greater than the width of said first protuberances.
- 14. Footwear according to claim 9, further comprising a top cover secured to upper surfaces of said forefoot portion, mid-foot portion and heel portion.
- 15. An insole according to claim 9, wherein said medial arch portion has a height greater than a remainder of said mid-foot portion, and extends approximately 40% of the distance from a medial side of said insole to a lateral side of said insole.
US Referenced Citations (13)