WO1999054004A1

WO1999054004A1 - Downhill ski device

Info

Publication number: WO1999054004A1
Application number: PCT/NO1999/000126
Authority: WO
Inventors: Egil Railo; Willy Railo
Original assignee: Egil Railo; Willy Railo
Priority date: 1998-04-17
Filing date: 1999-04-19
Publication date: 1999-10-28
Also published as: AU3446899A; NO305013B1; NO981756D0; NO981756A

Abstract

A downhill ski device, particularly for slalom, giant slalom and snowboarding, where, in an area at the foot point of the user, up to or in the ski sole, a pair of downwardly directed or outwards sloping blades (19) are arranged, which cover a length of 10-80 cm, and protrude 1-5 mm relative to snow surface.

Description

Downhill ski device

The present invention relates to a downhill ski device, particularly for slalom and giant slalom, according to the preamble of claim 1.

Background of the invention

A downhill ski device should slide with as little friction as possible with respect to a ground surface. Problems which arise too often with today's downhill ski devices include 1) unnecessarily long frictional skids with friction when decelerating and 2) backslide at the outer or inner ski: The latter is due to a side grip that is too weak, ie. the gripping power is too low aganst the snow. Slalom and giantslalom skis are particularly exposed in sudden curves. The time margins in high-level competitions are very small, possibly from 1/100 sec to several tenths of a second, ie. from mere centimeters to 3-4 meters in ordinary skiing.

In the majority of the curves constituting a part of a slalom course, the skier has to make use of his body in a backward manner, to gain enough pressure to make the skis turn. However, weight at the back gives friction against the snow surface and consequently braking effect. The lateral movements of the skier will also be unduly large because the weak grip at the side requires higher gravitational power/couple to get a grip that "sticks" to the ground surface.

Steel edges have been used for a long time to provide the skis with better grip on hard and icy courses. However, an edge with a right angle will provide a bad grip, regardless of the material.

From the German publication no. 24 03 944 (Naujoks) it is known to provide grooves lengthwise at some edge sections of the ski, which are limited outwards with a guide groove or a bevel. The purpose of these edges and the guide grooves are to give lead for 2 cross-country skis used in sloping ground. This provision of grooves is unsuitable in connection with alpine skis.

From German patent publication 41 19 816 (Kehl) "skating skis" with longitudinal ribs 5 in sloping lateral surfaces are known. The purpose of these ribs is to provide racing skis with course safety and directional stability as well, in a course that is mainly straightforward. These patterns made for course safety are unsuitable for alpine skis and particularly for slalom skis.

10 To maintain the grip of an edged slalom ski German publication 21 17 716 (Imgram) suggests putting a sloping protruding rib into the edge of the ski. There are corresponding ribs along the edges of the skis suggested in German patent publication 2 140 703 (Lorenzer).

15 It is common for these types of solutions, including the ones described above, in certain situations, to provide control so effectively that they prevent an effective turn around a geometric turningpoint, which is a requirement to be able to turn fast in slalom and giant slalom. Thus, the known solutions with ribs on the edges made of metal or another rigid material have a negative turning value. For the solution from German publication 24 03

20 944 it applies that this tracking will increase the friction considerably and in that way make these skis unsuitable for competitions.

Object

25

The main object of the present invention is to provide a ski particularly for slalom, giant slalom and snowboard competitions which gives the highest possible force and pressure in the direction of the dip and as little skid/friction laterally and backwards as possible. Furthermore, the ski should give the opportunity for a lower body

30 position, which reduces the air resistance, and at the same time make a reduction in the deflections of the body movements which must be carried out to master curves. The 3 physical strain on the skier will, in addition, be reduced such that he can make the most of his strength to master greater speed and create greater turn efficiency.

The ski required is one with strong/optimal lateral grip/turn grip, particularly in tougher/steeper courses, without sacrificing increased friction in the longitudinal direction due to the ski's grip efficiency. There is a special object to provide a ski which is suitable for use in more demanding courses, so the user can risk to increase his speed without losing the grip against the snow surface and without losing speed on the distances between the curves. The skier is forced to reduce speed, particularly in the curves, due to the risk of backsliding, and time is lost compared to the physical/technical chance, due to the unspecified safety margin he/she has to deal with. As a result, the skiing is also less offensive in the direction of the dip that is as straight as possible.

Furthermore, the ski provided must be able to be used during changing conditions like: different snow qualities, different speeds, abruptness in the elevation, curvature between the gates, the technique of the athlete, the size and weight of the skier, etc.

The invention

The invention is described in claim 1. Additional features of the invention is defined by claims 2-7.

An embodiment as described hereinafter, with grip irons along the ski, achieves a considerably improved lateral grip, which increases the possibility to turn faster. This is possible without any significant increase in friction caused by the edge groove in the direction of dip, compared with known skis designs. The edge groove is a combination of the grip iron and the hollow key on the inside. The depth of the edge groove from

0.5mm to 10mm, and its width from 1mm to 25mm.

The edge groove can preferably be designed in two alternative ways (depending on the varying racing conditions): 4

1) Sideways opening at the end of the edge groove, (see Fig. 5) that lead the snow. Snow and ice guided through the groove can then relatively easy be removed sideways.

2) Hollow key grooves that lead the snow backwards into the hollow key and out gradually under the ski.

The chosen solution will be dependent on different parameters, ie. the character of the course and the characteristics of the skier. The grip irons are mounted with the centre close to the central point of gravity of the user, measured at the foot of the skier. Displacements in relation to this point, will further on depend on the following parameters:

Course -abruptness -curvature -hardness/looseness in snowconditions/slide

Skier

-skiing technique -strength -weight -height

To adapt the ski to the above parameters the following variables are utilized/manipulated: - blade length

- placing of blade

- length, depth and width of groove

- the location of the groove pairs related to the foot of the athlete

- the radius of the inward bend of the ski - width of the blades

- the angle between blade and ski 5

The specific combination of the above-mentioned technical variables has to be adapted to the parameters described above. All these parameters can be used as a means to adapt the skis to the varying requirements. The design of the skis and the parameters will vary depending on the different conditions described above. The industrial design of the skis will therefore become "standardized custom-made" (as the golfclubs of today). However, all the variants will be made in terms of the main principle being that:

1) There is a grip iron or blade established along the outer edges of the ski

2) There is an edge groove established along the inner side of the grip iron of limited length

This combination yields a considerable increase in grip and turn power over today's established inventions. The edge groove that can be found at both edges of each ski has a limited length of 3-80cm (preferably 10-50cm). This limited length and design makes the skier capable of controlling/manipulating the blade in a curve, even if the blade gets a considerably stronger grip with the support than todays skis.

Such an improved side grip/turn grip means that a greater speed can be maintained, and consequently a better flow/share through the curve. This will force the strength downwards in the direction of the dip (not in the lateral or backwards direction) and thereby lead to an acceleration of the ski in the curves, producing a boosting effect. Less backweight is required from the skier to turn because the blade gets a better grip with the snow. The blade has, in addition, an inward bend which causes a turning effect made by the blade (in addition to the turning effect that the skier creates himself by weight transfer broadwise). Further, this will contribute to a shorter racing distance, by less distance to the gates, and in addition lead to less turn in between the gates.

Examples

The invention is described more precisely with reference to the drawings, where Fig. 1 illustrates a schematic view from the underside of a left ski that is designed according to the invention, with edge grooves on both sides, 6

Fig. 2-4 illustrate a cross section through a ski with different alternatives of the blade, while

Fig. 5 illustrates an enlarged section of the ski in Fig. 1 as seen from below.

Fig. 1 illustrates a ski with a relatively broad tip 11, an inwardly bending, tackled central part 12 and an outwardly bending rear part 13. Space for mounting of a ski binding (not shown) in the central part for fastening of a ski boot is provided at foot point 14, corresponding to the leg of the user, placed slightly behind a central point 15. The position of the foot point 14 can be adjusted in the longitudinal direction of the ski, for example approximately 30-100 mm, to the requirements of the user regarding centre of gravity, racingstyle etc. Grooves 16 and 17 are made in the ski sole 18 (Fig. 3) on each side (left and right side) of the ski in front of and behind the center point 15. The grooves 16 and 17 are embedded in the sole material, which can consist of plastic, or a composite of two or more materials, like laminated wood, plastic, glass fibre steel and aluminium. A sidewall or blade 19 made of steel or a similar cutting, smooth material, preferably of the same quality as in speed skates, is embedded to limit the grooves 16 and 17 broadwise outwards. The thickness of the blade 19 can be 1-3 mm, preferably 2 mm, with a relatively straight ground contacting edge. The length of the grooves and the sidewall can be from 3-80 cm. Depending on the range of use, the edges 19 of the blade can alternatively have a convex or concave bend.

The convex or concave bend of the blade can get close to zero at both ends in one embodiment. The blades 19 can follow the outward bend or tackling of the skis. The exterior blade 19 on the ski is in the example curved with larger radius than the interior blade to adapt the different turn radius for the inner ski and the outer ski.

Fig. 2 illustrates an embodiment of the blades 19 and how they can be integrated into the construction of the ski. The blades 19 can be made of an "L" shaped steel element with a leg 20 which can be embedded or adhered into the ski structure, either by original production or by inserting into milled slit 21. The cutting height is, in this example, lower than the ski thickness in such a way that the blade edge 22 in the topical area stays 7 retracted in a distance in the length of the blade groove, from 0.1-5 mm compared with the ski sole 18. The blade groove is shaped with a curved base (concave).

An alternative embodiment is illustrated in Fig. 3, where the blade edge 22 is level with the ski sole 18, while a further embodiment, where the edge 22 protrudes a distance of 0.1-5 mm from the ski sole 18, is illustrated in Fig. 4. This will vary with the length of the blade when a nonlinear solution is not selected, i.e. convex or concave, as above.

Both the lateral side of the ski and the blade make a substantial right angle (90°) with the ski sole in all of the examples. In an alternative embodiment the blades can differ from 90° in both directions (dependent on the racing condition). The blades 19 can alternatively be mounted as additional parts on the exterior of the ski or protrude at the crossing between the ski side and the ski sole in such a way that an edge groove is formed towards the ski sole.

An embodiment of the rear end of groove 16, where the edge groove approaches zero in the area 24, is illustrated in Fig. 5. The embodiment shown in the examples above can be modified in different ways. The grooves 16 and 17 can have a different shape than the one illustrated, for example with a V-shape formed between the ski sole 18 and the interior side of the blade. The blades 20 can also be integrated in a V-profile which forms a groove independent of the core material in the skis. The depth of the edge grooves can gradually appraoch zero at the rear edge.

Claims

Claims:

1) A downhill ski device, particularly for slalom, giant slalom and snowboards, which is supplied with a longitudinal rib on at least one of the sides, protruding at the crossing between the ski sole and the side to increase the side grip on smooth snow and ice surfaces, characterized in that in the ski sole in an area adjacent a skiers foot point, longitudinal edge grooves (16, 17) are arranged, situated in the ski core or externally, wherein downwardly extending blades (19) are arranged from said edge grooves.

2) Downhill ski device according to claim 1, characterized in that the blades expand over a distance of 10-80 cm and protrude 1-5 mm with reference to an adjacent sliding surface.

3) Downhill ski device according to claim 1 or 2, characterized in that the blades (19) are curved transversely equivalent to the inward bend of the skis, and wherein the outer blade has a larger radius of curvature than the inner blade.

4) Downhill ski device according to any one of the claims 1-3, characterized in that the rear end of the edge groove (16-17) is open sidewards to ease the removal of snow from the groove or approaches zero under the ski sole.

5) Downhill ski device according to any one of the claims 1-4, characterized in that the blade (19) on the inner edge of the skis is longer than the blade on the outer edge of the skis.

6) Downhill ski device according to any one of the claims 1-5, characterized in that the exterior blade (19) relatative to the skis makes an angle with the ski sole.

7) Downhill ski device according to any one of the claims 1-8, characterized in that the blades (19) are made of steel, with a straight, convex or concave curved bottom edge, a maximum height of 8 mm, preferably 2-5 mm, and with a blade edge width of

1-3 mm, preferably 2 mm.