Running surface for a ski and cross-country ski

Abstract

A running surface for a ski having a running surface profile that has slideback prevention elements with sliding surfaces which slope up counter to a sliding direction and merge into push-off flanks. The slideback prevention elements have at least one first ramp element having a longitudinally convexly curved sliding surface with a first radius of curvature (r1) and at least one second ramp element. The the second ramp element has a longitudinally convexly curved sliding surface with a second radius of curvature (r2) which is greater than that of the first ramp element.

Claims

1. A running surface for a ski having a running surface profile which has slideback prevention elements with sliding surfaces which slope up counter to a sliding direction and transition into push-off flanks, wherein the slideback prevention elements have at least one first ramp element having a sliding surface convexly curved in longitudinal direction with a first radius of curvature (r1) and at least one second ramp element, wherein the second ramp element comprises a sliding surface convexly curved in longitudinal direction with a second radius of curvature (r2) which is larger than that of the first ramp element.

2. The running surface according to claim 1, wherein the radius of curvature (r2) of the second ramp element is at least 4 times as large as the first radius of curvature (r1).

3. The running surface according to claim 1, wherein the first radius of curvature (r1) of the first ramp element is between 10 and 40 mm.

4. The running surface according to claim 1, wherein the second radius of curvature (r2) of the convexly curved second ramp element is between 200 and 500 mm.

5. The running surface according to claim 1, wherein each of the first and second ramp elements extends over 2 to 10 mm in the longitudinal direction.

6. The running surface according to claim 1, wherein the share of the extension of the sliding surface of the first ramp element with respect to the surface comprising a running surface profile having slideback prevention elements is between 3% and 60%.

7. The running surface according to claim 1, wherein the second ramp element adjoins the first ramp element directly in the longitudinal direction of the running surface.

8. The running surface according to claim 1, wherein the slideback prevention elements comprise first ramp elements and second ramp elements alternating in the longitudinal direction of the running surface.

9. The running surface according to claim 1, wherein the slideback prevention elements have at least one first ramp element and at least one second ramp element in the transverse direction of the running surface.

10. The running surface according to claim 1, wherein a ramp element is concavely curved in the transverse direction of the running surface according to a third radius of curvature (r3), wherein the third radius of curvature (r3) is between 100 and 200 mm.

11. The running surface according to a claim 1, wherein a ramp element is concavely curved in the transverse direction of the running surface according to a fourth radius of curvature (r4), wherein the fourth radius of curvature (r4) is between 100 and 200 mm.

12. The running surface according to claim 1, wherein the radii of curvature (r3, r4) of the ramp elements provided in the transverse direction of the running surface are substantially equal.

13. A cross-country ski having a sliding element comprising a running surface, wherein the running surface is designed according to claim 1.

14. The running surface according to claim 1, wherein the ski is a cross-country ski.

15. The running surface according to claim 1, wherein the running surface profile is in a central longitudinal portion of the running surface.

16. The running surface according to claim 1, wherein the radius of curvature (r2) of the second ramp element is at least 10 times as large as the first radius of curvature (r1).

17. The running surface according to claim 1, wherein the radius of curvature (r2) of the second ramp element is between 15 and 20times as large as the first radius of curvature (r1).

18. The running surface according to claim 1, wherein the first radius of curvature (r1) of the first ramp element is about 20 mm.

19. The running surface according to claim 1, wherein the second radius of curvature (r2) of the convexly curved second ramp element is about 360 mm.

20. The running surface according to claim 1, wherein each of the first and second ramp elements extends over 3 to 7 mm in the longitudinal direction.

21. The running surface according to claim 1, wherein each of the first and second ramp elements extends over about 5 mm in the longitudinal direction.

22. The running surface according to claim 1, wherein the share of the extension of the sliding surface of the first ramp element with respect to the surface comprising a running surface profile having slideback prevention elements is between 5 and 50%.

23. The running surface according to claim 1, wherein the share of the extension of the sliding surface of the first ramp element with respect to the surface comprising a running surface profile having slideback prevention elements is about 20%.

24. The running surface according to claim 1, wherein the slideback prevention elements have at least one first ramp element and at least one second ramp element in the transverse direction of the running surface, which transition directly into one another.

25. The running surface according to claim 1, wherein the second ramp element is concavely curved in the transverse direction of the running surface according to a third radius of curvature (r3), wherein the third radius of curvature (r3) is between 100 and 200 mm.

26. The running surface according to claim 1, wherein the second ramp element is concavely curved in the transverse direction of the running surface according to a third radius of curvature (r3), wherein the third radius of curvature (r3) is about 155 mm.

27. The running surface according to claim 1, wherein the first ramp element is concavely curved in the transverse direction of the running surface according to a fourth radius of curvature (r4), wherein the fourth radius of curvature (r4) is between 100 and 200 mm.

28. The running surface according to claim 1, wherein the first ramp element is concavely curved in the transverse direction of the running surface according to a fourth radius of curvature (r4), wherein the fourth radius of curvature (r4) is about 155 mm.

Description

(1) In the individual drawings:

(2) FIG. 1 shows a view of a portion of a cross-country ski which has a running surface including slideback prevention elements on the bottom face, which are composed of two types of convexly curved ramp elements, seen in the longitudinal direction of the ski, with different radii of curvature;

(3) FIG. 2 is an enlarged sectional view along line II-II of FIG. 1;

(4) FIG. 3 is an enlarged sectional view along line III-III of FIG. 1;

(5) FIG. 4 is an enlarged sectional view along line IV-IV of FIG. 1;

(6) FIG. 5 is an alternative design of the slideback prevention elements;

(7) FIG. 6 is an enlarged sectional view along line VI-VI of FIG. 5;

(8) FIG. 7 is a view of a cross-country ski having a further alternative design of the running surface;

(9) FIG. 8 is an enlarged sectional view along line VIII-VIII of FIG. 7;

(10) FIG. 9 is an enlarged sectional view along line IX-IX of FIG. 7; and

(11) FIG. 10 is an enlarged sectional view along line X-X of FIG. 7.

(12) FIG. 1 shows a section of a cross-country ski 1 having a sliding element 2 formed in a known manner which has a running surface 3 on the bottom face. In the illustrated region, which is beneath a ski binding (not shown), the running surface 3 has a running surface profile 4 for preventing slideback during cross-country skiing. The running surface profile 4 comprises slideback prevention elements 5 having sliding surfaces 10 sloping up counter to a sliding direction 6. At the rear end with respect to the sliding direction 6, the sliding surfaces 10 slope down to form push-off flanks 8 which extend substantially perpendicular to the longitudinal direction of the running surface 3. In the embodiment shown, the slideback prevention elements 5 are formed by ramp elements 9.

(13) As can be seen from FIGS. 1 to 3, the slideback prevention elements 5 comprise two types of ramp elements 9, in particular, with first ramp elements 9a and second ramp elements 9b being provided. The first ramp elements 9a have convexly curved sliding surfaces 10a, i. e. bent outside with respect to the running surface 3, with a first radius of curvature r1 of approx. 20 mm. In the design shown, the second ramp elements 9b also comprise convexly curved sliding surfaces 10b, however formed with a second radius of curvature r2 many times larger than that of the first ramp elements 9a. In the design shown, the second radius of curvature r2 is approx. 360 mm, resulting in substantially even sliding surfaces 10b.

(14) As can be seen from FIG. 1 in particular, in which the sliding surfaces 10a are illustrated shaded for better visibility, the share of the area of the sliding surfaces 10a with respect to the total area of the running surface profile 4 including slideback prevention elements 5, 5′ and/or a repeat unit of the running surface profile 4 (50 mm in the exemplary embodiment shown) is substantially 20%. In this way, the push-off behaviour of the cross-country ski may be improved while obtaining a particularly good sliding ability of the cross-country ski.

(15) As can further be seen from FIGS. 1 to 3, the first 9a and second ramp elements 9b are arranged in groups 12. The groups 12 of ramp elements 9 have a first 9a and a second ramp element 9b one after another in the longitudinal direction. In the transverse direction, alternating first 9a and second ramp elements 9b are provided as well.

(16) Between the groups 12 of ramp elements 9, further slideback prevention elements 5′ are provided. The further slideback prevention elements 5′ are composed of rows of stepped ramps that are formed sawtooth-like in their longitudinal section. The stepped ramps include a secondary step having push-off edges of its own, which is positioned lower than the push-off edges of the stepped ramps. Such a running surface profile 4 is known from EP 0 592 384 B1.

(17) FIG. 4 shows the design of the ramp elements 9 in the transverse direction of the running surface 3. In the exemplary embodiment shown, the second ramp element 9b has a concave curvature in transverse direction with a third radius of curvature r3, wherein the third radius of curvature r3 is 155 mm in the design shown. In this design, the sliding surface 10a of the first ramp element 9a has a concave curvature in transverse direction with a fourth radius of curvature r4, wherein the fourth radius of curvature r4 is also 155 mm in the design shown. Here, the concave radii of curvature r3, r4 are overlaid, advantageously resulting in a corrugated structure in the transverse direction of the running surface.

(18) Such a design prevents forming too small ramp elements 9 while not removing too much from the running surface when cutting the ramp elements 9 in a preferred manner, either. Of course, however, the radii of curvature r3, r4 may also be chosen to be different.

(19) FIGS. 5 and 6 show another exemplary embodiment in which each of the second ramp elements 9b adjoins the first ramp element 9a directly in the longitudinal direction of the cross-country ski. According to this, first ramp elements 9a and second ramp elements 9b are provided alternating longitudinally in the embodiment shown. In the transverse direction of the running surface, alternating first ramp elements 9a and second ramp elements 9b are provided as well, with adjacent ramp elements 9a, 9b directly transitioning into one another.

(20) Due to this, a significantly increased share of the area of the sliding surfaces 10a with respect to the total area of the running surface profile 4 including slideback prevention elements 5 and/or a repeat unit of the running surface profile 4 (50 mm in the exemplary embodiment shown) is obtained in this exemplary embodiment in contrast to the design according to FIGS. 1 to 4. Because of the alternating design in the longitudinal and the transverse directions, a share of the area of approx. 50% is obtained.

(21) A further exemplary embodiment according to the invention is shown in FIGS. 7 to 10.

(22) Here, a running surface profile 4 is shown, including mainly stepped ramps, each having a secondary step with a push-off edge of its own which is positioned lower than the push-off edges of the stepped ramps; such secondary steps are known from EP 0 592 384 B1 in particular.

(23) As can be seen from FIG. 8, ramp elements 9b having a radius of curvature r2 of approx. 360 mm are provided as part of these stepped ramps having a secondary step.

(24) In addition, however, regions are provided in the running surface profile 4 in which—as can be seen from FIG. 9—a ramp element 9a having a comparably small radius of curvature of approx. 20 mm seen in the longitudinal direction directly adjoins a ramp element 9b having the comparably large radius of curvature r1 of approx. 360 mm.

(25) Due to this, a significantly decreased share of the area of the sliding surfaces 10a with respect to the total area of the running surface profile 4 including slideback prevention elements 5 and/or a repeat unit of the running surface profile 4 (50 mm in the exemplary embodiment shown) is provided in this exemplary embodiment in contrast to the above statements. Substantially, a share of the area of approx. 8% is obtained, resulting in excellent push-off properties, in particular, for this exemplary embodiment.