U.S. patent application number 10/236783 was filed with the patent office on 2004-03-11 for footwear traction assist.
Invention is credited to Gould, Anne C., Gould, David B., Washburn, David K..
Application Number | 20040045190 10/236783 |
Document ID | / |
Family ID | 31990700 |
Filed Date | 2004-03-11 |
United States Patent
Application |
20040045190 |
Kind Code |
A1 |
Washburn, David K. ; et
al. |
March 11, 2004 |
Footwear traction assist
Abstract
Winter boots and shoes can be equipped with a removable traction
attachment that facilitates easy non-slip motion on ice, snow,
dirt, gravel, etc. The traction attachment can include an
elastomeric panel fitting the sole of the boot or shoe, an integral
front strap system fitting over the toe of the boot, and an
integral rear strap system fitting snugly on the heel of the boot.
The panel and strap systems have controlled elasticity, so that a
given size attachment can fit a range of different size boots or
shoes. Replaceable metal cleats are carried on downwardly
protruding sections of the elastomeric panel, to provide traction
assistance.
Inventors: |
Washburn, David K.;
(Portland, ME) ; Gould, David B.; (Kennebunk,
ME) ; Gould, Anne C.; (Kennebunk, ME) |
Correspondence
Address: |
Frederick R. Cantor, Esq
Post Office Box 87
SOUTH FREEPORT
ME
04078
US
|
Family ID: |
31990700 |
Appl. No.: |
10/236783 |
Filed: |
September 7, 2002 |
Current U.S.
Class: |
36/7.6 ;
36/7.3 |
Current CPC
Class: |
A43C 15/162 20130101;
A43C 15/061 20130101 |
Class at
Publication: |
036/007.6 ;
036/007.3 |
International
Class: |
A43B 001/10 |
Claims
What is claimed
1. A traction attachment for footwear, wherein the footwear
comprises a sole that includes a toe section, a heel section, and
an arch section connecting said toe and heel sections; said
traction attachment comprising: a flexible panel adapted to fit
against the footwear sole; a front strap means carried by said
panel for fitting around a toe of the footwear; and a rear strap
means carried by said panel for fitting around a heel of the
footwear; said flexible panel comprising a frontal area, heel area,
and shank area connecting the frontal area and heel area; said
shank area having a lesser vertical thickness than the frontal area
or the heel area, so that the shank area is stretchable while the
frontal and heel areas are substantially non-stretchable heel areas
are substantially non-stretchable, whereby the spacing between the
front strap means and the rear strap means can be varied to
accommodate a range of different footwear sizes.
2. The traction attachment of claim 1, wherein said panel has a
longitudinal axis; the frontal area, heel area and shank area of
said panel having differing width dimensions measured transverse to
the panel longitudinal axis; the width dimension of said shank area
being substantially less than the width dimension of said heel
area, whereby said shank area is stretchable along the panel
longitudinal axis.
3. The traction attachment of claim 2, wherein the width dimension
of said shank area is approximately thirty-five millimeters.
4. The traction attachment of claim 3, wherein said shank area has
a thickness of approximately 0.16 inch.
5. The traction attachment of claim 2, wherein said shank area has
concave side edges that merge smoothly with transverse edges of the
frontal area and heel area.
6. The traction attachment of claim 1, wherein said panel is a dual
density multi-layer assembly that includes a single upper
lamination, and two separate lower laminations; one of the lower
laminations being secured to the frontal area of the upper
lamination, the other lower lamination being secured to the heel
area of the upper lamination: said upper lamination forming the
shank area of the flexible panel.
7. The traction attacahment of claim 6, wherein said upper
lamination is formed of an elastomeric material having a relatively
low durometer, and each said lower lamination is formed of an
elastomeric material having a relatively high durometer.
8. The traction attachment of claim 7, wherein the durometer of
said upper lamination is approximately thirty-seven, and the
durometer of each said lower lamination is approximately
seventy.
9. The traction attachment of claim 1, and further comprising
plural replaceable cleats extending downwardly from said flexible
panel at spaced points along the panel peripheral edge; said plural
cleats including five cleats located on the frontal area of the
panel, and four cleats located on the heel area of the panel; the
shank area of said panel being devoid of cleats.
10. The traction attachment of claim 9, and further comprising
plural drainage grooves formed in the peripheral edge of said
flexible panel; said drainage grooves being located between the
cleats in the frontal area and heel area of the panel.
11. The traction attachment of claim 10, wherein each drainage
groove has a configuration in the plan view.
12. A traction attachment for footwear, wherein the footwear
comprises a sole that includes a toe section, a heel section, and
an arch section connecting said toe and heel sections; said
traction attachment comprising: a flexible panel adapted to have a
tension fit against the footwear sole, a front strap means carried
by said panel for fitting around a toe of the footwear, and a rear
strap means carried by said panel for fitting around a heel of the
footwear; said flexible panel comprising a frontal area, heel area,
and shank area connecting the frontal area and heel area; said
shank area having a lesser vertical thickness than the frontal area
or the heel area, so that the shank area is stretchable while the
frontal and heel areas are substantially non-stretchable, whereby
the spacing between the front strap means and the rear strap means
can be varied to accommodate a range of different footwear sizes;
said panel being a multi-layer assembly that includes a single
upper lamination, and two separate lower laminations; one of the
lower laminations being secured to the frontal area of the upper
lamination, the other lower lamination being secured to the heel
area of the upper lamination; said upper lamination forming the
shank area of the flexible panel; said upper lamination being
formed of an elastomeric material having a relatively low
durometer, and each said lower lamination being formed of an
elastomeric material having a relatively high durometer; each lower
lamination having plural protruding islands located at spaced
points along the panel peripheral edge; a threaded socket embedded
in each said island; and an externally threaded cleat, replaceably
secured within each said socket.
13. The traction attachment of claim 12, wherein said upper
lamination has plural openings aligned with the aforementioned
threaded sockets; said lower laminations having protuberances
extending into said openings, whereby the elastomeric material
surrounding each socket is reinforced against tearing or
rupture.
14. The traction attachment of claim 13, and further comprising
plural drainage grooves formed in the peripheral edge of said
flexible panel.
15. The traction attachment of claim 14, wherein each drainage
groove has a V configuration in the plan view.
16. The traction attachment of claim 12, wherein said rear strap
means is integral with the heel area of said flexible panel, said
front strap means and said rear strap means being individually
stretchable; the shank area of said flexible panel being
stretchable independently of the front strap means or the rear
strap means.
17. A traction attachment for footwear, wherein the footwear
comprises a sole that includes a toe section, a heel section, and
an arch section connecting said toe and heel sections; said
traction attachment comprising: a flexible elastomeric panel
adapted to fit against the footwear sole, a front strap means
carried by said panel for fitting around a toe of the footwear, and
a rear strap means carried by said panel for fitting around a heel
of the footwear; said flexible panel comprising a frontal area,
heel area, and shank area connecting the frontal area and heel
area; said flexible panel having plural downwardly protruding
islands located in the frontal area and heel area of the panel; a
threaded socket embedded in each said island; an externally
threaded cleat having a replaceable screw fit in each socket; and
plural drainage grooves formed in the peripheral edges of said
frontal area and said heel area.
18. The traction attachment of claim 17, wherein said drainage
grooves are interspersed with the cleats so that each drainage
groove is located between two cleats.
19. The traction attachment of claim 18, wherein each drainage
groove has a V configuration in the plan view.
20. The traction attachment of claim 17, wherein each said cleat
has an annular sharpened edge 60, designed to bite into icy
terrain.
Description
FIELD OF THE INVENTION
[0001] This invention relates to a traction attachment for
footwear, especially a traction attachment for use under wintry or
arctic conditions on icy or snow covered terrain.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] The invention concerns a traction device that can be readily
installed on a person's boot or shoe to provide improved traction
on snowy or icy terrain. The device can be likened to snow tires
for the feet. An important object of the invention is to provide a
traction attachment that is rugged and stable on the person's boot,
but is at the same time very light in weight. Typically, the
attachment weighs only about six ounces, such that it offers no
measurable hindrance to each foot movement.
[0003] A typical prior art traction attachment is shown in U.S.
Pat. No. 5,813,143, issued on Sep. 29, 1998 in the name of Michael
Bell. That patent shows an integral one piece unit molded out of
resilient material, e.g. rubber or polyvinyl chloride, and adapted
to fit onto a person's footwear (boot or shoe) to provide improved
traction for the person.
[0004] The molded unit includes a sole, toe encirclement at the
front end of the sole, and a heel encirclement at the rear end of
the sole. The heel encirclement includes side straps that are
stretchable, so that the molded unit can fit more than one size
boot or shoe. The shank area (or arch area) of the sole has a large
rectangular opening, apparently for reducing the resistance of the
molded unit to longitudinal stretching (while the unit is being
placed on the footwear). Several spikes, or cleats, are secured to
the bottom surface of the molded sole, to provide an improved
traction on snow or ice.
[0005] The present invention relates to a footwear traction
attachment that includes a flexible molded panel adapted to fit
against the footwear sole, an integral front strap means for
fitting around the toe of the footwear, and an integral rear strap
means for fitting around the heel of the footwear. The flexible
panel includes a shank area that is of reduced thickness and width
(compared to the heel and toe areas), such that the shank area is
stretchable longitudinally to vary the spacing between the toe and
heel areas of the panel. The panel construction enables the
traction attachment to be readily stretched, so as to fit a range
of different footwear sizes. Typically, four half sizes can be
accommodated with a single traction attachment size.
[0006] The front strap means and the rear strap means are formed of
a stretchable (elastomeric) material, so as to be stretchable
independently of the aforementioned panel. Therefore, the strap
means can fit snugly on differently shaped footwear toes or heels,
without regard to stretch or non-stretch of the flexible panel.
[0007] The traction attachment includes multiple metal cleats
replaceably secured to the flexible panel in the frontal area and
heel area of the panel (but not in the shank area). Each cleat has
a threaded post section that threads into a threaded socket
embedded in a raised (or protruding) island integrally formed on
the panel.
[0008] Each metal cleat can include an annular hollow cup-shaped
traction configuration having a sharpened annular edge designed to
bite deeply into ice or snow. Each metal cleat can be replaced
should it become worn or damaged.
[0009] In preferred practice of the invention, the flexible panel
(covering the sole of the footwear) is formed of two separate
layers of elastomeric material, i.e. an upper layer is preferably a
low durometer material, e.g. an elatomer having a durometer of
approximately thirty-seven. The lower layer is a high durometer
material, e.g. an elastomer having a durometer of about 70. The
upper layer material is selected primarily for its ability to
stretch (for achieving a snug fit on a range of different footwear
sizes and shapes). The lower layer material is selected primarily
for durability and abrasion resistance.
[0010] Upper and lower panel layers are bonded together along their
facing surfaces. Additionally, mechanical interlocking connections
are employed between the two elastomeric layers, to provide a
laminated panel resistant to delamination forces. In one preferred
arrangement, the lower panel is molded to have multiple
protuberances designed to fit into mating openings in the upper
layer, whereby the two layers are mechanically locked together so
as to resist shear forces that might tend to produce delamination
of the two layers.
[0011] The protuberances on the lower layer are vertically aligned
with the raised islands that anchor the aforementioned cleats.
Therefore, the cleat anchorages are reinforced against terrain
forces that might tend to disturb or tear the cleats from the
laminated panel. The cleats have improved resistance against
wobbling or shifting relative to the panel while the person's foot
is exerting a traction force on ice or frozen terrain.
[0012] The number of cleats employed on the traction attachment can
vary. In a preferred embodiment of the invention nine cleats are
employed. Five cleats are mounted on the frontal area of the
flexible panel, and four cleats are mounted on the heel area of the
panel. In order to minimize build up of ice or snow between the
traction attachment panel and the sole of the footwear, the panel
is molded to include drainage notches or grooves at spaced points
along the panel edge. As the person's foot applies downward
pressure on the traction attachment panel, any snow or ice
accumulations in the interface between shoe sole and attachment
tend to be squeezed into the drainage grooves and out onto the
terrain. The drainage grooves allow any ice, snow or water to drain
out of the interface between the footwear sole and traction
attachment, thus reducing the overall loading on the person's
foot.
[0013] As stated earlier, an important object of the invention is
to provide a traction attachment that is rugged and stable on the
person's foot, but is at the same time very light in weight. In one
particular embodiment of the invention, the traction attachment
weighs about six ounces. The low weight is attributable, at least
in part, to the fact that the traction panel is a laminated two
layer construction in which the upper layer is a low durometer
elastomer that is stretchable to conform to the footwear, while the
lower layer is a high durometer elastomer that is tough and
resistant to abrasion forces. By using two different elastomers it
is possible to optimize the wall thickness of each layer for its
intended function, while at the same time holding the overall
weight within reasonable limits.
[0014] Specific features and advantages of the invention will be
apparent from the attached drawings and description of an
illustrative embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a side elevational view of a traction attachment
constructed according to the invention. The footwear, on which the
attachment is installed, is shown in dashed lines.
[0016] FIG. 2 is a top plan view of the traction attachment
depicted in FIG. 1.
[0017] FIG. 3 is a sectional view taken on line 3-3 in FIG. 2.
[0018] FIG. 4 is a bottom plan view of FIG. 3 construction.
[0019] FIG. 5 is an enlarged cross sectional view taken on line 5-5
in FIG. 4.
[0020] FIG. 6 is a fragmentary view taken in the direction of arrow
6 in FIG. 5.
[0021] FIG. 7 is a bottom plan view of an elastomeric panel
component employed in
[0022] FIG. 8 is a top plan view of two other panel components used
in combination with the FIG. 6 component, to produce a multi-layer
panel, according to the invention.
[0023] FIG. 9 is a view taken in the same direction as FIG. 3, but
showing another form that the invention can take. FIG. 3 represents
a preferred embodiment of the invention.
DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
[0024] Referring to FIGS. 1 and 2, there is shown a traction
attachment 10 constructed according to the invention. The
attachment is shown in an installed position on a person's shoe or
boot 12, shown in dashed lines. The term "footwear" will be used
herein as a generic description for a person's boot or shoe of a
type that is worn by a person when walking, climbing or hiking on
snow or icy terrain. The traction attachment 10 is designed to
provide increased traction on snow or icy surfaces, as well as dirt
or gravel.
[0025] The traction attachment includes a flexible panel 14 adapted
to fit flatwise against the sole of footwear 12, a front strap
means 16 carried by the panel for fitting around the toe of the
footwear, and a rear strap means 18 carried by the panel for
fitting around the heel of the footware. Each strap means 16 or 18
is formed of a low durometer elastomer, so that the strap means can
stretch to a limited extent for snugly fitting differently sized or
differently shaped toes and heels of footwear.
[0026] Flexible panel 14 carries nine downwardly projecting steel
cleats 44 that provide traction in ice, snow, dirt, gravel, etc.
FIG. 4 is a bottom view of panel 14, showing the cleat 44 pattern.
Five cleats are mounted on the frontal section 31 of the panel.
Four cleats 44 are mounted on heel section 32 of the panel. Shank
area 33 of the panel is devoid of cleats.
[0027] FIG. 5 shows a mechanism for anchoring each metal cleat 44
to panel 14. Each cleat includes a threaded post that threads into
a metal socket 42, embedded or encapsulated, within a thickened
section of panel 14, whereby the socket is precluded from tearing
away from the panel. Each metal cleat can be replaced should it
become worn or damaged.
[0028] As indicated earlier, the flexible panel 14 is secured to
the footwear (boot or shoe) 12 by a front strap means 16 and a rear
strap means 18.
[0029] Strap means 16 is a low durometer elastomer that includes a
front central strap element 19 located on the longitudinal axis 20
of the footware attachment, and two side strap elements 21 and 22
connected to each side edge of panel 14. The strap elements merge
together to form a central bridge 24 that is adapted to overlie the
upper surface of the toe on footware 12. The strap elements are
elastic so as to fit snugly on a range of different footwear toe
sizes and styles.
[0030] Strap means 18 includes a cross piece 26 adapted to fit
against a rear central surface of the footware heel, and two strap
elements 27 and 28 extending downwardly and forwardly from each end
of the cross piece to connect with edge areas of panel 14. The
cross piece and associated strap elements 27 and 28 are formed of a
low durometer elastomer, such that the cross piece can stretch to a
limited extent for conforming to differently dimensioned footwear
heel surfaces. Plural ridges 29 (FIG. 3) are formed on the front
surface of cross piece 26, to ensure an improved grip of the cross
piece on the footwear heel surface.
[0031] The cross sectional dimensions of the cross piece and strap
elements are selected, in conjunction with the durometer of the
elastomer, to achieve a desired elasticity of the front strap means
16 and rear strap means 18, whereby the strap mechanisms are
enabled to snugly fit a range of different footwear toe and heel
styles and sizes. The durometer of the elastomer used for strap
means 16 and 18 is preferably about thirty-seven.
[0032] Panel 14, is a dual density multi-layer laminated
construction formed out of two different elastomers. FIGS. 7 and 8
show the panel components in plan view. The upper layer (or
lamination) 30 is show in FIG. 7; it includes a frontal section 31,
heel section 32 and shank 33 connecting the frontal and heel
sections. The upper layer is formed of a relatively soft elastomer
having a durometer of about thirty-seven. The vertical thickness of
layer 30 is preferably about 0.16 inch. Nine toothed openings 34
are formed in layer 30 to mate with similarly shaped protuberances
36 formed on two lower layers 38 and 40 (when the lower layers are
bonded to the upper layer).
[0033] Lower layer 38 has a shape that conforms to the shape of
frontal section 31 of the upper layer, so that when layer 38 is
bonded to the undersurface of layer section 31, protuberances 36
fit snugly into the mating openings 34 to form a mechanical
interlock between layers 30 and 38.
[0034] Lower layer 40 has a shape that conforms to the shape of
heel section 32 of layer 30. Four protuberances 36 on the upper
surface of lower layer 40 fit into the aligned toothed openings 34
on heel section 32 to form a mechanical interlock between layers 30
and 40 (when layer 40 is bonded to layer 30).
[0035] Protuberances 36 are vertically aligned with certain
internally threaded metal sockets 42 that serve as anchorages for
hardened steel cleats 44 (FIG. 5), such that protuberances 36
transfer a fraction of the traction force from the cleats to upper
layer 30 of panel 14, while at the same time reinforcing the
elastomeric material in contact with sockets 42. Protuberances 36
absorb shear loadings on the interfaces between layers 38 and 40,
and upper layer 30, thereby protecting the laminated panel from
delamination forces that occur when the person exerts a pushing or
pulling force on icy terrain.
[0036] Lower layers 38 and 40 are formed of an elastomer having a
relatively high durometer, e.g. an elastomer having a durometer of
about seventy. The layer material is selected primarily for
toughness and abrasion resistance. The aim is to preclude the metal
cleats 44 from exerting oblique forces on the elastomeric material
in contact with sockets 42, which could eventually tear the sockets
out of the elastomer. The nominal thickness of each layer 38 or 40
is only about 0.16 inch. However, protuberances 36 effectively
increase the layer thickness in those areas that are used to mount
the cleat sockets.
[0037] By comparing FIGS. 7 and 8, it will be seen that the
laminated panel 14 is relatively thick in the frontal section of
the panel and in the heel section of the panel. The shank area 33
of the panel is formed solely by upper layer 30, such that the
shank area is relatively thin in the vertical (thickness )
direction.
[0038] Shank area 33 has a cross sectional dimension that enables
the shank area of the laminated panel to stretch longitudinally,
while the frontal section and heel section of the panel are
substantially non-stretchable. In this regard, the high durometer
layers 38 and 40 tend to add stretch resistance to the panel, while
the low durometer shank area 33 has the desired elasticity needed
for localized longitudinal stretching of the panel, e.g. for
stretching the panel to fit a range of different footwear sizes.
Panel 14, is a dual density panel, that is adapted to have a
tension fit binding on a range of different size footwear.
[0039] In FIG. 5 the longitudinal axis of panel 14 is referenced by
numeral 20. Shank area 33 of the panel has a width dimension 52
(transverse to axis 20) that is substantially less than the
corresponding width dimension for the frontal section or heel
section of the panel. Typically, width dimension 52 will be about
thirty-five millimeters. The cross sectional dimension of the shank
area 33 (thickness and width) is selected, along with the durometer
of panel lamination (layer) 30, so that the panel stretch action is
confined to shank area 33.
[0040] As viewed in FIG. 5, edges 53 of shank area 33 are concave
so that the shank width dimension is increased where the shank area
connects with the transverse edges 54 and 55 of the panel frontal
section and heel section. The increased width dimension strengthens
those parts of the shank area most likely to tear or rupture when
the panel is subjected to a longitudinal stretching force, i.e. the
anchored ends of the shank that cannot relieve the stress in the
form of strain.
[0041] Although not readily apparent from the drawing the front
strap means 16 and rear strap means 18 are integral with upper
layer 30 of panel 14, preferably by molding the panel layer 30 and
strap means together in a single step molding operation. The panel
layer 30 and both strap means are formed of the same low durometer
elastomer so as to have a desired elasticity.
[0042] In adapting a given size traction attachment to fit a range
of different footwear sizes and shapes, there are two independent
stretching actions that can take place. First, panel 14 can be
stretched longitudinally in shank area 33 to vary the spacing
between the front strap means 16 and rear strap means 18. Second,
the front strap means 16 can be independently stretched to have a
snug fit on various different footwear toe sizes and styles.
Similarly, the rear strap means 18 can be independently stretched
to fit a range of footwear heel configurations. In this regard,
cross piece 26 curls around a substantial length of the heel
surface so as to be capable of substantial changes in cross piece
length.
[0043] Referring to FIGS. 4 and 5, it will be seen that the steel
cleats 44 are located at spaced points along the peripheral edge of
panel 14, giving the traction attachment a wide stance tractive
action for improved footware stability. The central area of panel
14 proximate to the longitudinal centerline 20 is occupied by two
sets of chevron type treads 57 and 58 extending downwardly from
frontal layer 38 and heel layer 40. Chevrons 57 have rearwardly
facing ve rtical surfaces that stabilize the panel against slippage
in the rearward direction, whereas chevrons 58 have forwardly
facing vertical surfaces that stabilize the panel against slippage
in the forward direction. The chevrons augment the tractive action
of cleats 44.
[0044] As stated earlier, each metal cleat 44 is threadably mounted
in a metal socket 42 encapsulated within one of the lower layers 38
or 40 of the laminated elastomeric panel. Each metal cleat includes
an annular cup-like protrusion that has an annular sharpened edge
60 designed to bite into icy terrain so as to achieve a tractive
action. The annular wall of the hollow cup-like protrusion has a
screw driver slot 62 therein that facilitates installation or
removal of the cleat from the associated socket 42. All of the
cleats are similarly constructed.
[0045] Each metal socket 42 is encapsulated within an island 64
protruding from the laminated panel 14, to provide lateral support
for the socket. As shown in FIG. 5, the side surface of the
protruding island is stepped to provide some traction in soft
terrain. The islands are molded integrally with elastomeric
laminations (layers) 38 and 40.
[0046] As previously noted, metal sockets 42 are vertically aligned
with protuberances 36 on elastomeric layers 38 and 40. Therefore,
the elastomeric material encircling each socket 42 is reinforced by
the associated protuberance 36. Shear loadings on the metal cleats
44 tend to be resisted by the associated protuberances 36 that are
mechanically locked to the upper lamination 30 of the cleat-support
panel. Protuberances 36 tend to resist panel delamination
forces.
[0047] The laminated panel 14 is provided with plural drainage, and
is provided with plural drainage grooves 66 interspersed with metal
cleats 44 at spaced points along the peripheral edge of the panel.
As shown in FIG. 4, there are four V-shaped drainage grooves 66 in
the frontal portion of the laminated panel, and two drainage
grooves 66 in the heel portion of the panel. Each drainage groove
is located between two cleats, so as to be capable of shedding snow
or water that might accumulate in the spaces between cleats. The
drainage grooves extend through the entire panel thickness, so that
water or ice accumulations in the crack interface between the
footwear sole and upper surface of panel 14, can migrate easily
into the drainage grooves.
[0048] The apex of each V-shaped drainage groove 66 forms a
potential weak point that could lead to tearing or rupture of the
elastomeric materials. To strengthen the panel against such
rupture, each lower layer 38 or 40 has molded reinforcement ribs 68
that provide local reinforcements at the apex of each V-shaped
drainage groove, as well as longitudinal rigidification of layers
38 and 40.
[0049] The traction attachment is designed to achieve a combination
of useful properties, including localized elasticites enabling a
given size attachment to fit a range of different footwear sizes, a
good stable support for each metal cleat, drainage for ice of snow
accumulations, and a relatively low overall weight.
[0050] As shown in FIG. 4, the longitudinal centerline 20 is a
straight line, such that the traction attachment is capable of
fitting on either a left boot or a right boot. In actual practice
the attachment is made in two versions, i.e. for a left shoe or a
right shoe; the longitudinal centerline is slightly curved.
[0051] FIG. 3 shows a preferred embodiment of the invention. FIG. 9
shows an alternate construction that can be employed. In the FIG. 9
version panel, 14 is a single molded elastomer having a durometer
of approximately fifty. The FIG. 9 panel represents a compromise
between elasticity and durability.
[0052] The drawings show specific forms that the invention can
take. However, it will be appreciated that the invention can be
practiced in various forms and configurations.
* * * * *