Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.
Referring to
Near the ends of the ski, the undersurface 18 is a distance 22a, 22b above a plane 24 parallel to the planar portion 20 due to the convexity of the undersurface 18. The distance 22b at the forward end of the ski 10 is preferably less than the distance 22a at the rearward end. For example, a 185 cm ski may have a distance 22a of 2 cm and a distance 22b of 1.5 cm.
Raised tail and tip portions 26a, 26b are formed at the rearward and forward ends of the ski 10, respectively. A fore-body portion lies between the tip portion 26b and the mid-portion 16, while an aft-body portion lies between the tail portion 26a and the mid-portion of the ski. The raised portions 26a, 26b typically have a slope substantially greater than the remainder of undersurface 18. For example, a 185 cm ski may have a tail portion 26a having a length of 18.45 cm and a height of 5.98 cm. The tip portion 26a of such a ski 10 may have a length of 18.45 cm and a height of 5 cm.
In some embodiments, the tail portion 26a is higher than the tip portion 26a. Increasing the height of the rearward tail portion enables a skier to more easily ski and land jumps backwards. Inasmuch as a skier normally has much better balance and control when skiing and landing facing forward, increasing the height of the tail portion 26a helps the skier avoid burying the tail portion 26a in the snow.
Referring to
The sidewalls 28a of the aft-body portion are separated by a width 32 near the tail portion 26a that is substantially less than a separation width 34 near the boundary between the straight or convex sidewalls 28a and the concave sidewalls 30 of the mid-portion 16. In a like manner, the sidewalls 28b of the fore-body are separated by a width 36 near the tip portion 26b that is substantially less than the width 38 near the boundary between the fore-body and the mid-portion 16.
In the preferred embodiment, the width 38 is greater than the width 34. The width 36 is also preferably greater than the width 32, such that the shovel of the ski 10 is wider than the tail. For example, in a 185 cm ski the width 38 may be 135 mm whereas the width 34 is 134 mm. In the same ski, the width 36 may be 125 mm whereas the width 32 is 120 mm.
The concave sidewalls 30 of the mid-portion 16 are separated by a waist width 40 generally at a narrowest point 42 of the ski (or at the deepest sidecut) along the concave sidewalls 30. The concave sidewalls 30 may describe an arcuate path or may describe straight lines from endpoints 44a, 44b of the concave sidewalls to the narrowest point 42. In any case, the waist has a width less than the average of the widths 38 and 34, such that a sidecut is formed.
The concave sidewalls 30 along the mid-portion 16 have a length 46 that is substantially less than the entire length of the ski 10. In some embodiments, the length 46 is between about 20% and about 60% of the total length of the ski 10. In other embodiments, the length 46 is between about 25% and about 40% of the total length of the ski 10. In still other embodiments, the concave portion forms about 32% of the total length of the ski. For example, in a 185 cm ski, the concave portion may have a length of 60 cm centered on the middle of the ski 10. The length 46 of the concave sidewalls 30 may also be chosen to be substantially equal to a length of the binding 12 secured to the ski 10.
The waist width 40 of the concave sidewalls 30 is typically between 1% and 20% less than either the width 38 at the boundary between the sidewalls 28b and the concave sidewalls or the width of the widest point of the ski. In other embodiments, the waist width 40 is between 1.2% and 5% less than the widest point of the ski or the width 38. In still other embodiments, the waist width 40 is about 1.5% less than the widest point of the ski or the width 38. For example, in a 185 cm ski, the width 40 may be 133 mm whereas the width 38 is 135 mm.
In any of the ski regions, the width may increase with a constant slope as shown by plot 54 or have variable slope as shown in plot 56 such that the sidewalls 28a, 28b, the concave sidewalls 30, or both, are arcuate in shape. There may be inflection points within the sidewalls 28a, 28b such that the rate at which the width increases with distance along the ski varies. Where the onvex sidewalls 28a, 28b contain inflection points, portions of the sidewalls 28a, 28b may be concave. For example, the rate at which width increases may be less near the raised portions 26a, 26b than near the concave sidewalls 30 or at another point along the sidewalls 28a, 28b.
The novel sidewalls of the ski 10 disclosed herein provide a ski that is suitable for skiing on both powder and hard snow. The concave sidewalls 30, although relatively short (compared to a conventional ski) and having a relatively slight concavity, enable a skier to use the edge of the ski to turn on hard snow. At the same time, the relatively small extent of the concave sidewalls 30 does not detract significantly from the performance of the ski in powder. The area of the ski located under the foot of the user is not greatly reduced resulting in a broad support surface when landing jumps. A broad support area is beneficial in reducing the extent to which a skier sinks into the snow on landing or downwardly pressuring the ski and therefore reducing the likelihood that the edge of the ski will catch on the snow to throw the ski sideways and cause the skier to fall.
Referring to
Alternatively, the cable running along the fore-body of the ski is independently adjustable from the cable running along the aft-body of the ski. Preferably, this is accomplished by fixing the cable fore and aft of the binding. Then the adjustment mechanisms can independently adjust the tension. This may be desirable for fine tuning the ski based on the terrain (e.g., a stiffer aft-body for steep powder skiing). The cable may alternatively be fixed under the binding or separate fore and aft cables may be used.
A homing device broadcasting a signal detectable to pinpoint the location of the ski may also be secured to the ski. It may be part of the structure of the ski or attached with other systems, such as the binding or tensioning system. In the event the ski binding releases in deep snow, the ski often becomes buried and lost. The homing device enables the skier to locate the ski.
While the preferred embodiments of the invention have been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.