WO1991007889A1

WO1991007889A1 - Device for cross-country ski boot

Info

Publication number: WO1991007889A1
Application number: PCT/NO1990/000184
Authority: WO
Inventors: Arild T. Karlsen; Emil Abry; Halldor Skard
Original assignee: Alfa Skofabrik A/S
Priority date: 1989-12-05
Filing date: 1990-12-05
Publication date: 1991-06-13
Also published as: AU6894691A; NO168744B; NO894860L; NO894860D0; NO168744C; NO170314B; NO913950D0; NO913950L; NO170314C

Abstract

A cross-country ski boot (1) provided with a detachable ankle support (2) which is rotatable about a rotational axis (B) disposed transversely to the longitudinal direction (A) of the ski boot by means of joints (3a, 3b) secured to the outer side (1a) and the inner side (1b), respectively, of the ski boot (1). The ankle support (2) is capable of limited movement transversely to, i.e. toward and away from, the rotational axis (B) at the inner side (1b) of the ski boot (1).

Description

DEVICE FOR CROSS-COUNTRY SKI BOOT

The present invention relates to an improvement on a cross- country ski hoot to adapt the hoot for use in both classical and freestyle skiing (ski-skating). In connection with the development of cross-country skiing in recent years, resulting in the emergence of two different competitive styles within cross-country racing — namely classical and freestyle — there have also been developed both skis and boots that are suited to each of the mentioned styles/events.

In other words, from the equipment used for classical skiing there have been developed skis and cross-country boots that are adapted to the special technique used in freestyle/ski- skating. This means that the skiers must possess two sets of skiing equipment in order to be able to do their best in each of these two branches of skiing.

This leads to considerable expense, which is accepted in top- level athletics, but must be regarded as a heavy financial burden on the broader level of sports participation, par¬ ticularly among children and youth who are training in both styles of skiing.

With the change that has taken place in connection with selection of the course/terrain for ski trails, which as a result of increased competition have become more difficult in that the trails now have harder and steeper downhill runs including turns by which to distinguish among the skiers, it is now popular to use different designs/embodiment forms of cross-country boots with and without ankle support. This has to do with the snow conditions, also, since heavier, more sluggish snow reduces the speed of the downhill runs, in which case a cross-country boot with little or no ankle support may be used instead of a cross-country boot having an ankle support. A ski boot without ankle support will of course be lighter than a boot having such support, and is preferable on heavy snow.

There is a known ski boot in which the actual leg portion which constitutes an ankle support is articulately joined to the lower part of the boot in order to permit a rotational movement back and forth in the boot's longitudinal direction. This boot, which is shown in Norwegian design application no. 890155, seems to be constructed particularly for ski-skating and thus provides ankle support during the performance of the ski-skating technique.

The purpose of the present invention is to provide a cross¬ country ski boot where the above mentioned disadvantages are eliminated, which cross-country boot may be adapted to both of the mentioned styles of skiing, namely classical cross¬ country skiing and freestyle/ski-skating. This is achieved according to the invention by means of the characteristic features specified in the characterizing clause of the following claim 1 and in the subsequent dependent claims.

There is provided in accordance with the invention a cross¬ country boot equipped with a detachable ankle support which is rotatable about a joint on each side of the ankle in a forward/backward direction.

The cross-country boot can thus be used for, respectively, classical style skiing when the ankle support is removed, and freestyle (ski-skating) with the ankle support attached.

In performing the ski-skating technique, the ski is placed with its outer edge in the snow, whereafter the ski is turned or twisted over on the sole plate thereof until only the inner edge rests against the snow surface. This is to achieve a maximal glide and kick-off. Such a technique could be inhibited by the ankle support if this were permanently fixed relative to its rotational points or fulcrum. To achieve maximum interaction between an ankle support and the skier's leg when practicing said technique, it is important that the ankle support permit a limited bending latitude across the foot, or optionally an adjustable bending latitude.

This is achieved by means of the characteristic features recited in the following dependent claims.

An embodiment example of a cross-country boot — hereafter in this description referred to simply as a ski boot -- with an ankle support in accordance with the invention will be explained more fully in the following, with reference to the figure, where: the single figure shows in perspective a ski boot with removable ankle support.

The ski boot 1 is provided with a detachable ankle support 2 which is rotatable about a rotational axis B disposed transversely to the longitudinal direction A of the ski boot 1 by means of joints 3a,3b secured to the outer side la and the inner side lb, respectively, of the ski boot 1. The ankle support 2 is capable of limited movement transversely to — i.e., toward and away from — the rotational axis B at the inner side lb of the ski boot 1.

The ankle support 2 comprises a leg 4a,4b projecting upwards from each joint 3, which legs are connected to one another at their upper ends by means of a leg band 5 adapted to encircle and be securely fastened onto a user's leg above the ankle, said band 5 being equipped with a fastening means 6.

The illustrated fastening means is a strap buckle disposed on one of the sides of the leg band, which buckle engages with a strap secured to the other side of the leg band 5. Instead of such a buckle there may also be used a Velcro fastener, where the inside of the strap is provided with one set of gripping means and the front part of the leg band 5 is provided with the other complementary set of gripping means, which on being pressed together hold the leg band 5 securely about the user's lower leg above the ankle.

The joint 3b on the ankle support 2 at the inner side lb of the ski boot 1 is designed to permit, in addition to the rotational movement, a limited radial movement in order to attain the ankle support's limited movement transverse to the rotational axis B. This will be explained further in the following.

Each of the joints 3a,3b comprises a pivot bolt 7 which projects out of and is connected with the sides la,lb of the ski boot 1 for engagement with bearing holes 8a,8b at the opposing lower side sections 2a,2b of the ankle support 2. The bearing hole 8b at the inner side section 2b of the ankle support 2 is elongated in order to permit the above mentioned radial movement and thereby the ankle support's limited movement transversely to the rotational axis B. In this embodiment form of the inner joint 3b, the inner leg 4b of the ankle support 2 is securely fastened to the leg band 5.

In an alternative embodiment form, the inner leg 4b of the ankle support 2 comprises a telescopic structure, such that the length of the inner leg 4b may be altered with the inclination of the foot. In this way the mentioned slot 8b in the joint 3b may be omitted.

A further alternative embodiment form of the ankle support, as shown in the figure by solid lines, consists of the inner leg 4b of the ankle support 2 being attached slidably in its longitudinal direction to the leg band 4. This is achieved as shown in the figure by the leg band's having a transverse groove 11 in which the inner leg 4b is slidably disposed. Said groove may be undercut, with a complementary configura¬ tion of the side edges of the leg 4b for slidable securing of the inner leg 4b. To limit the sliding movement of the leg 4b, a slot 12 is provided at the upper section of the leg 4b, which slot is longitudinal relative to the longitudinal direction of the leg 4b, and which engages with a screw 13 screwed into a threaded hole or sleeve in the leg band 5.

The length of the slot 12 determines the flexibility or bending potential of the ankle support 2 transversely to the longitudinal direction of the ski boot.

Through insertion of small rubber buffers at one or both ends of the slot 12, the length of the sliding movement may be reduced or regulated, while there is also achieved a mild braking effect of the sliding movement at the end/ends of the slot 12.

Through this sliding movement of the leg band 5 of the ankle support 2 relative to the inner leg 4b, said leg will be subjected to a bending strain, which means that the inner leg 4b must be somewhat flexible. This can be achieved as shown in the figure, for example, by means of transverse attenuation grooves 14 in the inner leg 4b.

The legs 4a,4b should both consist of a somewhat flexible, non-splintering material such as, for example, slightly flexible artificial materials. It is, however, conceivable to produce the legs 4a,4b from other rigid materials, such as aluminum, but then there must be special arrangements with the inner leg 4b for the attainment of the requisite flexibility.

The ankle support 2 should be capable of being rotated forward with as little resistance as possible during use. On the other hand, it may be relevant to limit the backward rotation of the ankle support 2. This is particularly the case in downhill runs where the skier thereby can attain a certain degree of support from the ankle support 2 against the leg when the skier stands with his legs parallel while skiing downhill. The leg will in this way be held at a desired angle in relation to the foot and thus the ski, and when the skier crouches down and leans his weight backward, the forward part of the sli is lifted slightly to achieve better glide and increased speed.

A blocking means for attaining the aforementioned limitation of the backward rotation of the ankle support 2 may be provided by mounting an adjustable stop means 9 at one or preferably both of the joints 3a,3b.

The stop means 9 comprises, as shown in the figure, a finger 9a on the lower side section 2a,2b of the ankle support, for engagement with a boss 9b releasably fastened into one of a plurality of apertures 10 provided at the side/sides la,lb of the ski boot.

By screwing the boss or the finger 9a out of one of the apertures 10 and fastening it into a different hole, one may regulate the backward rotation of the ankle support.

Claims

P a t e n t C l a i m s

1.

A cross-country ski boot (1) provided with an ankle support (2) which is rotatable about a rotational axis (B) disposed transversely to the longitudinal direction (A) of the ski boot (1), by means of joints (3a,3b) secured to the outer side (la) and the inner side (lb), respectively, of the ski boot (1), c h a r a c t e r i z e d i n that the ankle support (2) is detachably fastened at the joints (3a,3b).

2.

The ski boot according to claim 1, c h a r a c t e r i z e d i n that the ankle support (2) is capable of limited movement transversely to — i.e., toward and away from — the rotational axis (B) at the inner side (lb) and/or the outer side (la) of the ski boot (1).

3.

The ski boot according to claim 1 or 2, c h a r a c t e r i z e d i n that the ankle support (2) comprises a leg (4a,4b) projecting upwards from each joint (3), which legs are connected with one another at their upper ends by means of a leg band (5) adapted to encircle and be securely fastened onto a user's leg above the ankle, said band (5) being equipped with a fastening means (6).

4.

The ski boot according to claim 1 and/or 2, c h a r a c t e r i z e d i n that each of the joints (3a,3b) comprises a pivot bolt (7) which projects out of and is connected with the sides (la,lb) of the ski boot (1) for engagement with bearing holes (8a,8b) at the opposing lower side sections (2a,2b) of the ankle support (2), and where the bearing hole (8b) at the inner and/or outer side section (2a,2b) of the ankle support (2) is elongated for the attainment of said radial movement.

5.

The ski boot according to claim 2, c h a r a c t e r i z e d i n that the inner side section (2b) of the ankle support (2) has alterable length.

6.

The ski boot according to claim 5, c h a r a c t e r i z e d i n that the inner side section (2b) of the ankle support (2) is flexible.

7.

The ski boot according to claim 3, 5 or 6, c h a r a c t e r i z e d i n that the inner leg (4b) of the ankle support (2) Is attached slidably in its longitu¬ dinal direction to the leg band (5).

8.

The ski boot according to claim 3, 5 or 6, c h a r a c t e r i z e d i n that the inner leg (4b) of the ankle support (2) is flexible.

9.

The ski boot according to any one of the preceding claims, c h a r a c t e r i z e d i n that at least one of the joints (3a,3b) is equipped with an adjustable stop means (9) for limiting the backward rotation of the ankle support.

10.

The ski boot according to claim 9, c h a r a c t e r i z e d i n that the stop means (9) comprises a finger (9a) on the lower side section(s) (2a,2b) of the ankle support for engagement with a boss (9b) releasably fastened into one of a plurality of apertures (10) provided at the side/sides (la,lb) of the ski boot.