U.S. patent number 3,635,482 [Application Number 05/056,089] was granted by the patent office on 1972-01-18 for ski and method of manufacture.
This patent grant is currently assigned to AMF Incorporated. Invention is credited to Rudolph G. Holman.
United States Patent |
3,635,482 |
Holman |
January 18, 1972 |
SKI AND METHOD OF MANUFACTURE
Abstract
A new and improved snow ski and a method of making said ski. The
ski comprises a plastic foam core surrounded by one or more fiber
glass layers and a predetermined fiber glass winding. A unique top
surface assembly including a coiled spring edge and a bottom
surface assembly, the various embodiments of which are described
hereinafter, are then mounted about the core assembly to form a
finished ski.
Inventors: |
Holman; Rudolph G. (Santa Ana,
CA) |
Assignee: |
AMF Incorporated (N/A)
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Family
ID: |
10042052 |
Appl.
No.: |
05/056,089 |
Filed: |
June 29, 1970 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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705706 |
Feb 15, 1968 |
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Foreign Application Priority Data
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Mar 30, 1967 [GB] |
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14,485/67 |
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Current U.S.
Class: |
280/610; 156/242;
156/245; 273/DIG.8 |
Current CPC
Class: |
A63C
5/12 (20130101); A63C 5/048 (20130101); A63C
5/052 (20130101); Y10S 273/08 (20130101) |
Current International
Class: |
A63C
5/048 (20060101); A63C 5/052 (20060101); A63C
5/12 (20060101); A63C 5/00 (20060101); A63c
005/12 () |
Field of
Search: |
;280/11.13
;156/242,245 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1,351,207 |
|
Dec 1963 |
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FR |
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1,380,102 |
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Oct 1964 |
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FR |
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1,435,153 |
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Mar 1966 |
|
FR |
|
Primary Examiner: Hersh; Benjamin
Assistant Examiner: Smith; Milton L.
Parent Case Text
This application is a continuation of application Ser. No. 705,706
filed Feb. 15, 1968, now abandoned.
Claims
What is claimed is:
1. A snow ski comprising:
a core assembly including a lightweight and elongated preformed
inner core member having a contour including a turned-up nose and
bottom camber, and a filament positioned about the preformed core
member in a helical pattern along the length of the core
member,
a bottom surface assembly including a plastic running surface and a
metal running edge positioned along opposite edges of said running
surface, and
a layer of urethane material positioned around said filament wound
core assembly, said layer of urethane material forming at least
part of the outer surface of the ski and bonding said bottom
assembly to the filament wound core assembly.
2. A snow ski comprising:
a preformed core assembly including a lightweight inner core having
a contour including a turned-up nose and bottom camber, a layer of
matted fiber glass reinforcing positioned at least partially around
the preformed core assembly and a layer of unidirectional fiber
glass material reinforcing positioned at least partially around the
layer of matted fiber glass reinforcing, and a filament positioned
over the reinforced preformed core in a helical pattern,
a top and side assembly including an upper portion and downwardly
extending side portions positioned on the core assembly, and
a bottom surface assembly including a plastic running surface and a
metal running edge mounted along each edge of said running surface,
said bottom surface assembly being mounted on the bottom of said
ski.
3. A snow ski in accordance with claim 2 wherein:
the inner core comprises a polyurethane foam material.
4. A snow ski in accordance with claim 3 further including:
a binding plate positioned within the polyurethane foam core having
the reinforcing layer positioned thereover.
5. A snow ski in accordance with claim 2 wherein:
the filament comprises a fiber glass thread applied about the
reinforcing material in a predetermined helical winding along the
total length of the ski.
6. A snow ski in accordance with claim 5 wherein:
the helical winding is applied about the reinforcing layer at an
angle ranging from approximately 20.degree. to 45.degree. to the
longitudinal axis of the ski.
7. A snow ski in accordance with claim 2 wherein:
the bottom surface assembly comprises a polyethylene base and a
pair of metal running edges each having a pair of legs arranged in
a substantially L-shaped configuration, said running edges being
mounted along the outer edges of the base with one leg of the L
mounted along the upper surface of the polyethylene base and the
other leg extending downwardly along the edge of the base to
provide a gripping edge for the ski.
8. A snow ski in accordance with claim 7 wherein:
the metal running edge comprises a steel running edge having a
shorter lower leg and a longer upper leg, said upper leg being
mounted along the upper portion of the polyethylene base, said
upper leg including a plurality of apertures extending therethrough
and slotted portions connecting said apertures to the inner portion
of said edge to permit flexing of said metal edge.
9. A snow ski comprising:
an elongated foam core contoured in the general shape of a finished
ski,
a layer of fiber glass reinforcing mounted about at least part of
said foam core,
a bottom assembly including a pair of metal running edges and a
running surface therebetween, and
a layer of urethane plastic material at least partially enveloping
the reinforced core, said layer of urethane plastic forming at
least part of the outer surface of the ski and bonding the bottom
assembly to the reinforced core.
10. A snow ski according to claim 9, wherein the core is reinforced
with fiber glass.
11. a snow ski according to claim 10, further comprising:
a plastic top surface layer affixed to the upper surface of the
urethane layer.
12. A snow ski according to claim 10, wherein a metallic binding
plate is embedded in the reinforced core.
13. A snow ski according to claim 9, wherein said core is
reinforced with:
at least a partial layer of unidirectional fiber glass filaments,
and
at least a partial layer of matted fiber glass.
14. A snow ski according to claim 9, wherein the urethane layer
includes portions forming the sides of the ski.
15. A snow ski according to claim 9, wherein the coating of the
coated fiber glass filament is epoxy.
16. A snow ski comprising:
a bottom assembly including:
a strip of plastic providing a running surface on the bottom
thereof,
a pair of metal running edges, each having a vertical extending
portion that is positioned against the side of the strip of plastic
and a flange that lays on top of the adjacent portion of the strip
of plastic, and
an adhesive placed on the top of at least a portion of the plastic
strip for bonding the metal edges to the strip of plastic,
a core assembly, and
a layer of urethane plastic or the like at least partially
encapsulating the core assembly and forming at least part of the
outer surface of the ski, said layer of urethane plastic being in
contact with the adhesive placed on top of the bottom assembly to
bond the bottom assembly to the core assembly.
17. A snow ski according to claim 16, wherein the flanges of the
metal running edges are provided with apertures and portions of the
urethane plastic are placed in the apertures.
18. A method of making a snow ski, comprising the steps of:
forming a foam core,
winding a fiber glass filament about the reinforced foam core in a
predetermined pattern,
bonding a metal running edge to the outer edges of a plastic strip
to form a bottom surface assembly, and
bonding the bottom surface assembly to the filament wound
reinforced foam core with a layer of urethane plastic that forms
part of the outer surface of the ski.
19. A method of making a snow ski according to claim 18, further
comprising the step of reinforcing said foam core with fiber glass
before winding the fiber glass filament therearound.
20. A method of making a snow ski according to claim 18, wherein
said fiber glass filament is epoxy coated and is wound about said
reinforced foam core in a helical pattern.
21. A method of making a snow ski according to claim 18, wherein
said step of bonding the bottom surface assembly to the
filament-wound reinforced foam core comprises forming a layer of
plastic at least partially around the filament-wound reinforced
foam core.
22. A method of making a snow ski according to claim 21, wherein
said plastic is a urethane or the like.
23. A method of making a snow ski according to claim 18, further
comprising the step of curing the wound, reinforced foam core
before the bottom assembly is bonded thereto.
24. A method of making a snow ski, comprising the steps of:
placing a metal running edge on both sides of a plastic running
surface,
bonding the metal running edges to the plastic running surface with
a urethane plastic or the like, and
bonding the thus formed assembly to a core assembly by at least
partially enveloping the core assembly with a urethane plastic or
the like that forms at least part of the outer surface of the ski
and placing the thus enveloped core assembly against the urethane
plastic used to bond the metal edges to the plastic running
surface.
Description
This invention relates to a new and improved snow ski and a method
of making said ski. The growing popularity of winter sports such as
skiing caused manufacturers to devote more attention to technical
problems affecting ski performance. Considerable effort has,
consequently, been devoted to developing new ski designs which
represent a marked improvement over the prior art. However, despite
the advances which have been made, the manufacture of skis
generally requires a great number of manual operations which
necessarily increase product cost. Furthermore, the characteristics
or properties of commercially available skis are often deficient in
one or more respects as attempts are made to compromise between
various design factors.
The present invention relates to a new and improved ski which is
superior in performance to present high-quality skis and also lower
in cost. In addition, the unique ski comprising this invention
readily lends itself to mass production methods which permit
further economies.
SUMMARY OF THE INVENTION
The object of this invention is to provide a new and improved ski
and a method of manufacturing said ski. The ski thus produced is
light in weight and is of a predetermined strength and thickness.
As a further advantage, it is possible to build a ski having the
desired characteristics at a lower cost than conventional skis.
The unique ski of the present invention comprises a plastic foam
core having a predetermined fiber glass covering and a separate
fiber glass winding to produce the desired properties in the
finished product. A top assembly including a coiled spring outer
edge and a bottom assembly are then bonded to the core assembly to
form the finished ski. The invention in its various embodiments
includes a number of novel top and bottom assemblies which are
mounted about the core. Since the various manufacturing operations
may be readily adapted to mass production techniques, the subject
skis may be produced at a lower unit cost.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention will be more clearly
understood when viewed in conjunction with the accompanying
drawings wherein:
FIG. 1 is a top view of the unique ski comprising the present
invention;
FIG. 2 is a side view of the subject ski illustrating the
configuration of said ski;
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG.
1 showing the tip section of the ski;
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG.
1 illustrating the tail section of the ski;
FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG.
1 showing the construction of the ski tip portion;
FIG. 6 is a cross-sectional view taken along the line 6--6 of FIG.
1 showing the waist portion of the ski;
FIG. 7 is a cross-sectional view taken along the line 7--7 of FIG.
1 illustrating the construction of the tail portion of the ski;
FIG. 8 is a view showing the tip protector mounted on the tip
portion of the ski;
FIG. 9 shows the coil spring upper edge employed in the preferred
embodiment of the ski;
FIG. 10 is a top view of a typical L-shaped running edge employed
in the preferred embodiment;
FIGS. 11-16 illustrate the unique core structure of the subject ski
and its method of manufacture with the various views being as
follows:
FIG. 11 is a cross-sectional view of the core assembly;
FIG. 12 is a broken-away perspective view of the core assembly to
better illustrate its various elements:
FIG. 13 is a view of the molded core prior to winding;
FIG. 14 is a view of a typical binding plate;
FIG. 15 illustrates the positioning of the various core elements
within a mold for forming the polyurethane core structure;
FIG. 16 illustrates the winding operation wherein a fiber glass
thread is wrapped about the molded core in a predetermined pattern,
and;
FIGS. 17-24 illustrate various other embodiments of the invention
employing the wound fiber glass core illustrated in the foregoing
figures. The different embodiments are described at length in the
specification.
FIG. 25 is an isometric view of another embodiment of a ski
according to the invention.
FIG. 26 is a sectional view of the ski shown in FIG. 25.
FIG. 27 is an isometric view of a reinforced core for the ski shown
in FIGS. 25 and 26.
FIG. 28 is an exploded view of the ski shown in FIGS. 25 and
26.
FIG. 29 is an enlarged view of a portion of the ski shown in FIG.
28.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, the present invention comprises a
new and improved ski 10 which includes a core 11 of material such
as polyurethane foam having one or more binding plates 12 and a
plurality of fiber glass layers 13 and 14 positioned thereover and
a fiber glass winding 16 wrapped thereabout in a predetermined
pattern. The above components comprise the core assembly 17 which
remains essentially the same for the various embodiments of the
invention. This core assembly 17 is combined with a top and side
surface assembly and a bottom surface assembly to form the
completed ski shown in FIGS. 1 and 2.
The core assembly 17, which is illustrated in greater detail in
FIGS. 11-16, includes a lightweight polyurethane foam core 11
having one or more binding plates 12 mounted near the upper surface
intermediate the end portions of the core 11. The binding plates 12
may be of a fiber material or a metal such as aluminum. The binding
plates 12 are designed to anchor the connecting members or screws
which secure the ski bindings (not shown) to the ski 10. It is to
be understood, of course, that the binding plates 12 may differ
somewhat from the configuration of FIG. 14 and may comprise one or
more separate elements. In addition, a generally Z-shaped anchor
member 12' is disposed beneath one of the rear binding plates 12.
This anchor member 12' is for the purpose of receiving side screws
or the like for anchoring ski bindings from along the side edge of
the ski, whereas the plates 12 are adapted to receive top screws or
the like. This means that the ski of the invention can receive
almost any type of ski binding currently available on the
marketplace. The Z-shape imparted to the member 12' has the
additional advantage that it can be readily used with skis having
different widths. This is because the width of the member 12' can
be readily varied merely by pinching or stretching its Z-shape.
An inner layer 13 of matted glass material and an outer layer 14 of
unidirectional glass material are placed about the core 11 and over
the binding plates 12 during forming of the core 11. A treated
fiber glass winding 16 is then wrapped about the glass layers 13
and 14 in a helical winding pattern which may be varied as desired
to impart predetermined characteristics to the ski 10. The separate
elements of the core assembly 17 are bonded together in a
subsequent molding operation. Both the front and rear portions of
the core 11 include formed winding tabs 21 in order to mount the
ski 10 during the winding operation, the protruding tabs 21 being
removed at a later time.
The core assembly 17 is formed by first placing a full-length
unidirectional strip 14 of glass material in the lower half of a
mold 22 and placing a full-length strip 13 of glass mat on top of
the unidirectional layer 14, see FIG. 15. The glass mat 13 is
tucked into the corners but extends over the parting line of the
mold 22. The binding anchor members 12 and 12' are located in the
mold 22 and the components of the polyurethane foam 11 are then
mixed and immediately poured into the mold 22. A second strip 13 of
glass mat is placed over the foam 11 and a second layer 14 of
unidirectional glass is placed thereover. The mold 22 is closed and
the assembly is allowed to cure. After curing the excess of the
fiber glass mat 13 along the parting line of the mold is trimmed.
The resultant core assembly comprises a complete envelope of glass
mat enclosing the foam body 11 with the binding anchors 12 and 12'
formed in place at the inner face of the mat 13. The top and bottom
core surfaces include a full-length strip 14 of unidirectional
glass exposed at its outer surface.
The core assembly is mounted axially by means of the winding tabs
21 at each end on a winding apparatus. One or more fiber glass
threads 16, see FIG. 16, which are either pretreated or fed through
a resin bath are wrapped about the core in a helical winding
pattern along the length of the ski. Means such as not shown spaced
pins or staples inserted into the side edges of the mold formed
core may be provided to prevent thread slippage as the filament 16
is wound about the core. The thread or threads 16 are generally
wound in a long helix at an angle of approximately 20.degree. to
the longitudinal axis of the ski 10 at the waist or central portion
of the ski, and at an angle of approximately 45.degree. at the tail
and tip sections, and at an angle of from 20.degree. to 45.degree.
in the transitional areas between the waist section and the tail
and tip sections. The molded core rotates about its lengthwise axis
during the winding operation illustrated in FIG. 16, and a carriage
15 which feeds or lays the filament 16 onto the rotating ski moves
back and forth along the ski while the ski is being rotated. The
speed of rotation of the ski and the stroke of the carriage are
programmed with respect to each other so that the same winding
pattern can be successively repeated. Thus, successive skis
processed through the winding machine according to a given program
tape will all have the same characteristics in the final product.
For skis having somewhat different characteristics then a different
program tape is selected. Thus, the invention makes it possible to
repetitively produce a great variety of skis having predetermined
characteristics, and this can be done at minimal labor cost and
without the end product being subject to variations due to errors
in human judgement. For example, if two skis run according to the
same program are cut transversely at the same place, an examination
of the cut sections will show that both skis have the same number
of filament wound threads. Also, the invention makes it possible to
uniformly control the desired build of filament along the length of
the ski. This of course, is possible because the program tape can
uniformly vary the speed of the rotating ski and the lengthwise
traveling carriage with respect to each other independent of human
judgement. In the preferred embodiment of the invention the
filament 16 is resin coated just before it is deposited on the
molded ski form. After winding the filament wound molded ski form
17 is placed in a mold to cure the resin on the filament, to
permanently band the filament to each other and to the molded ski
form. This provides a ski structure which is completely enveloped
or encapsulated by a glass fiber helical winding. After curing of
the filament resin then the means, such as not shown side pins, for
temporarily holding the helical filament turns in place during the
actual winding operation can be removed.
On one preferred embodiment illustrated in FIGS. 1-10, the top
surface assembly 20 comprises a plastic material 23 such as
polyurethane which is molded in place over the sides and upper and
lower portions of the core assembly 17 so as to completely surround
and be banded thereto as well as a bottom subassembly 25 to be
described shortly. The top surface member 23 may of course, be
molded separately as a channel-shaped member and then assembled to
the core 17. In any event, the top surface assembly 20 as thus
described is a relatively simple, strong and low-cost structure.
Since there are no separate side members and the entire top surface
assembly 20 may be formed in a single-molding operation, an
additional savings in manufacturing costs results.
A protective metal edge 24 is also molded in place along the upper
edges of the top surface assembly 20 during mold-forming of the
plastic 23. The metal edge 24 is preferably a helically wound wire
or coil which prevents top edge damage and has other advantageous
characteristics such as a high-quality decorative effect.
Conventional aluminum edges having a high-tensile strength
producing a stiffer ski while the coiled spring edge 24 is
extensible and yet may be made of a tough stainless steel without
impairing the ski properties. As shown in FIG. 9, the edge 24 may
also comprise separate left-hand and right-hand coils to provide
herring bone decorative effect. In addition, the coil can extend
the full length of the ski, or be only at the front portion since
that part is more vulnerable to top edge damage.
The bottom surface assembly 25 comprises, in the embodiment of
FIGS. 3-7, a polyethylene running or skiing surface or strip 26 and
steel running edges 27 positioned along the outer edges of the
plastic strip 26. The parts 26 and 27 are bonded to each other by a
suitable material 26' such as a soft resilient urethane plastic.
The material 26' completely covers the top of skiing strip 26 to be
firmly bonded thereto. It also completely encapsulates the part 27
except for its outer running edge corner, and fills to-be-described
openings 31, 39 formed therein, so as to firmly lock the part 27 in
place with respect to the part 26. The running edges 27 may be
essentially L-shaped in cross section and may also include a
plurality of elongated apertures 39, see FIG. 10, extending
therethrough. The apertures 39 may include a slot 31, see FIG. 8,
extending to the inner portion of the edge 27 at the tip and tail
sections of the ski to facilitate bending. The apertures 39 and
slots 31 assist in anchoring the edge 27 in position. It is
entirely possible, however, to use a continuous L-shaped running
edge 27 without the refinements of FIGS. 8 and 10.
FIG. 3 discloses the tip portion 33 of the ski 10 in cross section
including the foam core 11, the epoxy-resin-filled glass filament
wound portion 34 of the molded core and the outer polyurethane
molded cover and sides 23 having the integral helically wound wire
form 24 to prevent top edge damage and the polyethylene base or
running surface 26. A bottom tip protector 36, see also FIG. 8, is
welded to the running edges 27 and bonded to the running surface 26
to form a separate subassembly which can be stored and rapidly
assembled to the core assembly 17 and top surface assembly 20
during manufacture.
FIG. 4 shows a view of the ski tail portion 41 including the
above-described elements and having a tail guard 42 formed at the
end of the ski 10. Tail guard 42 may be an integral formation on
material 23. FIGS. 5, 6 and 7 illustrate, respectively,
cross-sectional views of the nose section 33, waist section 44 and
the tail section 41 of the ski 10. The sections 41, 33 and 44 vary
both in width and in height in order to provide the ski
configuration of FIGS. 1 and 2. Additionally, the waist section 44
is shown raised above the ground 46 due to the bottom camber of the
ski 10. The shown configuration of the ski is obtained during the
mold operations formed on the ski form 17 prior to winding and
during curing of the resin on the winding.
Briefly, in practicing the invention, first the molded ski form
comprising parts 11, 12, 12', 13 and 14 is formed in mold 22. Then
the filament 16 is wound on the molded ski form and the resin on
the filament is cured in a mold. At this time the ski form 17 is
given some additional shaping to finalize its basic configuration.
The bottom subassembly 25 comprising parts 26, 26', 27 and 36 will
have been separately formed in readiness to be united with the ski
form 17 and its top assembly 20 into a finished product. This is
accomplished by positioning coil 24 in mold, then some plastic
material 23, then ski form 17, then some more material 23 on top of
ski form 17, and then finally bottom subassembly 25 over the
additional plastic material 23 and closing the mold so as to cause
the plastic material 23 to completely envelope the ski form 17 and
bond itself to the ski form and the bottom subassembly 25.
The unique ski 10 which is described above and is produced by the
method of the present invention represents a considerable
improvement over conventional skis. The subject ski is light in
weight and well dampened to minimize vibration. Furthermore, since
the winding operation can be carefully controlled, it is possible
to obtain the precise strength and thickness for particular
conditions of use. For example, it is possible to vary the
application of the winding in order to produce a ski having the
desired "flex." A low polar moment of inertia also results and
tends to improve the maneuverability of the ski since the weight
distribution can be carefully controlled during the winding
operation.
FIGS. 17-24 illustrate various embodiments of the present invention
employing the core assembly 17 in unique combinations with
different top-surface assemblies and bottom surface assemblies. The
drawings represent typical cross section views across the waist of
the ski.
For example, FIG. 17 proposes a core 17 surrounded by a shell of
soft resilient polyurethane material and a polyethylene base 48
having a pair of metal running edges 49 embedded in the corner
positions thereof. A metal member may also be embedded in the upper
corner portions of the polyurethane shell 47 as described in the
preferred embodiment. However, the particular polyurethane material
may be selected to resist top edge damage without the use of
protective metal edges.
In FIG. 18, the core assembly 17 is enclosed within a polyurethane
envelope 51. The upper protective edges 52 and the bottom running
edges 53 are embedded in the polyurethane material. The ski also
includes a polyethylene running surface 54 which is bonded to the
polyurethane envelope 51. A further modification may include a
plastic inlay 55 along the upper surface as shown in FIG. 19.
The ski shown in FIGS. 20 and 21 comprises a core assembly 17, a
top surface assembly 56 and a polyethylene base 57. The top surface
assembly 56 comprises a vacuum-formed plastic shell having aluminum
edges 58 with anchoring means 60 formed thereon. The base 57
includes steel running edges 59 which provide the necessary holding
capacity on ice or snow. The ski of FIG. 21 also includes a plastic
inlay strip 61 which may be a phenolic material bonded along the
upper surface thereof.
FIG. 22 shows an embodiment of the invention wherein the ski walls
62 are formed integral with a base portion 63 to provide a simple,
strong and low cost structure. The "box" thus formed provides an
ideal cavity for loading and curing the wound core 17. Furthermore,
the flexing of the ski is somewhat less influenced by the steel
edges 64 since they are resiliently bonded together with the base
65. The shell 62 and 63 may consist of polyethylene material which
is bonded to a polyethylene base 65. The base plastic material and
the shell plastic material may be the same or different plastic and
may be another color if desired. An upper plastic strip 76 and
metal edges 77 are also bonded over the upper portion of the
ski.
The ski of FIG. 23 comprises a soft resilient polyurethane cap 66
and a polyethylene base 67 bonded thereto in order to encapsulate
the core assembly 17. A unique running edge 68 is molded into the
base 67. The edge 68 is of smaller cross section than conventional
edges and does not impart its tensile strength to resist bending of
the ski. The edge 68 may also slide (with frictional restraint)
lengthwise within its enclosure but it is locked in and cannot be
removed laterally. It may, therefore, be readily replaced and it
also dampens the vibration of the ski and insulates the shocks from
the main body of the ski. A similar edge could also be used along
the upper portion of the ski and in several of the other previously
described ski designs.
FIG. 24 shows a ski including the core 17, upper protective edges
69, separate die-cut side strips 71, an upper plastic strip 72 and
a lower base strip 73 having running edges 74 bonded thereto, all
of which are bonded to the core 17.
In the above embodiments, a tip protector and a tail bumper may be
included in the various moldings where it proves advantageous.
Otherwise, they may be separately mounted to the ski. The overall
arrangement for the front and rear portions of the various designs
is primarily the same as the preferred embodiment with the
necessary changes to reflect the different structures.
Another embodiment of the invention shown in FIG. 18 is depicted in
FIGS. 25-29. Referring to those FIGS., a ski 75 includes a
lightweight urethane foam core 11 fabricated in the general shape
of a ski and reinforced by one or more fiber glass layers, such as
unidirectional layers 14, as most clearly shown in FIG. 27. A
binding plate 12 is embedded in the core intermediate the ends
thereof and near the upper surface thereof. The reinforced core is
then wound with a resin treated fiber glass filament 16 in a
helical winding pattern, which may be varied as desired to impart
predetermined characteristics to the ski 75.
A bottom assembly 25 which includes a pair of L-shaped running
edges 27 joined adjacent the tips thereof, as at 36, are bonded to
a polyethylene running surface 26 by a layer of soft resilient
urethane plastic. The bottom assembly is formed by laying the metal
running edges 27 over the polyethylene running surface 26. The
running edges are L-shaped in cross section (FIG. 29) such that
when laid over the running surface 26 a portion thereof will extend
on top of the sides of the running surface. A plurality of
elongated apertures 39 are formed on the top surface of the running
edges. The soft urethane material is placed completely over the top
of the assembled metal running edges and running surface assembly
with the material filling in the elongated apertures 39 to aid in
forming a secure bond between the metal and the polyethylene.
The thus formed bottom assembly is joined to the wound reinforced
core by an envelope of polyurethane 23 which, when reacting with
the urethane layer used in bonding the bottom assembly together,
forms a firm bond therebetween. This latter process is done in a
mold such that the polyurethane envelope 23 is formed to a desired
contour such as to form the sides and top of a ski. Finally, a
layer of plastic material 61 is placed on the top of the ski for
decorative and appearance purposes. The various portions of the ski
are shown in cross section in FIG. 26 and in an exploded view, FIG.
28.
What has been described above are merely illustrative examples of
the application of the principles of the invention. Numerous other
arrangements may be readily devised by those skilled in the art
which will embody the principles of the invention and fall within
the spirit and scope thereof.
* * * * *