Ski Boot

Abstract

Ski-boot comprising a rigid shell shaped to accommodate the foot, and a rigid cuff which is shaped to surround the ankle and is hinged on the shell so to be rotatable about a transversal reference axis; the shell being inferiorly provided with a front sole and with a substantially duckbill-shaped front appendix which protrudes from the tip of the shell to form an extension of the front sole, and is structured so as to engaged in the front jaw of a specific ski fastening device; the front appendix having, on each lateral side, a respective side groove which starts on the appendix upper face at a distance from the appendix tip ranging between 10 and 20 millimetres, and continues by flanking the shell tip while increasing its depth, so to form a descending slope above which a corresponding prong of the front jaw of the ski fastening device is arranged.

Description

The present invention relates to a ski boot.

More in detail, the present invention relates to an alpine or Telemark ski boot, use to which the following description refers purely by way of example without this implying any loss of generality.

BACKGROUND OF THE INVENTION

As is known, more recent alpine or Telemark ski boots are made up of a rigid shell made of plastic material and which is shaped so as to accommodate the foot of the user, and is inferiorly provided with a front sole and with a rear heal usually made of non-slip elastomeric material; of a rigid cuff made of plastic material and which is C-shaped so as to surround the ankle of the user from behind, and is hinged to the upper part of the shell so as to rotate about a transversal reference axis substantially coinciding with the articulation axis of the ankle; of an inner liner made of soft and thermal insulating material and which is removably inserted into shell and cuff, and is shaped so as to surround and protect both the foot and the lower part of the leg of the user; and of a protective upper tongue made of plastic material, which has its lower end hinged to the shell, immediately above the tarsal-phalangeal area of the foot, and extends along the upper part of the shell up to beneath the cuff, so as to cover the longitudinal slit of the shell which allows the shell to be temporarily widened in order to facilitate the insertion of the foot into the liner.

The rigid shell of alpine and Telemark ski boots is also frontally provided with a substantially duckbill-shaped, protruding appendix, which protrudes from the ogival tip of the shell while remaining locally substantially coplanar to the front sole, and is structured so as to be firmly and stably coupled, though easily releasable manner, to the toepiece of the ski fastening device which in turn is firmly attached on the middle part of the downhill ski.

In the practice of Telemark skiing, it is also essential to be able to significantly lift the heal of the ski boot from the ski below, while always keeping the tip of the boot firmly anchored to the ski, whereby the front part of the shell of Telemark ski boots is provided at the top with a programmed-deformation gusseted folding which straddles the metatarsal area of the foot, so as to allow the front part of the shell to bend forwards with respect to the tip, so as to go along with the natural movement of the skier's foot.

The ski fastening device is structured instead so as to go along with both the deformations of the shell as a result of the bending of the skier's foot, and with the cyclical lifting of the boot heal from the ski below, thus always and in any event keeping the tip of the boot, or better the duckbill-shaped appendix of the shell, firmly anchored to the ski.

More in detail, the toepiece of the most recent ski fastening devices is structured so as to fix the boot above the ski, tightening the shell at the front sole or solely at the duckbill-shaped protruding appendix, thus allowing the shell to rotate, with respect to the ski beneath, about a horizontal reference axis which is arranged immediately close to the duckbill-shaped protruding appendix and is locally perpendicular to the center line plane of the boot and to the center line plane of the ski.

Unfortunately, recent studies on the kinematics of the movement of the alpine and Telemark ski boot on the ski have shown that, during the initial part of the lifting movement of the boot heal from the ski, the ski fastening devices are not able to transfer the push of the skier to the ski beneath, thus resulting in a part of the skier's movement not implying a forward push.

SUMMARY OF THE INVENTION

Aim of the present invention is to improve the kinematic interaction between the alpine or Telemark ski boot and the ski fastening device so as to increase the performance of the skier without however significantly increasing the cost of ski bindings and Telemark ski boots.

In compliance with these aims, according to the present invention there is provided a ski boot as defined in claim 1 and preferably, though not necessarily, in any one of the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the accompanying drawings, which show a non-limiting embodiment thereof, in which:

FIG. 1 shows the middle segment of a downhill ski with on top a Telemark ski boot realized according to the teachings of the present invention;

FIG. 2 is a side view of the front part of the Telemark ski boot shown in FIG. 1; and

FIG. 3 is a perspective view of the front part of the boot shown in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIGS. 1 and 2, reference number 1 indicates as a whole a ski boot, and in particular a ski boot specifically structured to do alpine or Telemark skiing.

Boot 1 is adapted to be fastened in known manner on a general alpine or downhill ski 2, by means of a ski fastening device 3 which is firmly attached on the middle segment of ski 2, immediately below the boot 1, and is structured so as to firmly fix the tip 1a of boot 1 to the body of ski 2, thus allowing, when needed, the rear part 1b of boot 1 to lift from ski 2 following an elastic deformation of the front part of boot 1 and/or following a rotation of boot 1 about a reference axis R, which is arranged immediately close to tip 1a of boot 1 and is horizontally oriented so to be locally substantially perpendicular to the center line plane of the boot and to the center line plane of the ski.

The ski fastening device 3, traditionally called ski binding, is a component which is already widely known in the field, and hence won't be further described other than to clarify that one of the most common models of the alpine and Telemark ski fastening device is shown and disclosed in European Patent EP-1790396.

In particular, in the example shown, the ski boot 1 is particularly suitable for being fastened on the back of ski 2 by means of model NTN ski bindings manufactured by Norwegian company ROTTEFELLA AS.

With reference to FIG. 1, boot 1 essentially comprises: an outer rigid shell 4 made of plastic or composite material and which is shaped so as to accommodate the foot of the user, and is inferiorly provided with a front sole 5 and a rear heal 6 both preferably, though not necessarily, made of non-slip elastomeric material; of a rigid cuff 7 made of plastic or composite material and which is substantially C-shaped so as to surround the ankle of the user from behind, and is hinged to the upper part of shell 4 so as to freely oscillate about a transversal reference axis A, which is substantially perpendicular to the center line plane of the boot (i.e. perpendicular to the sheet plane in FIG. 1), and also locally substantially coinciding with the articulation axis of the ankle of the user.

More in detail, cuff 7 is freely pivotally fixed on shell 4 by means of two connecting hinges 8, which are located on the outer and inner sides of shell 4 and of cuff 7, aligned along axis A so as to allow the cuff 7 to freely oscillate/rotate on shell 2, while always remaining locally substantially coplanar to the center line plane of the boot.

With reference to FIGS. 1, 2 and 3, shell 4 is also provided with a substantially duckbill-shaped, front protruding appendix 9, which protrudes from the ogival tip of shell 4 while remaining locally substantially coplanar to the front sole 5, and is structured so as to be coupled/engaged in the substantially horseshoe-shaped front jaw 10 of the toepiece of the ski fastening device 3.

More in detail, the front protruding appendix 9 protrudes from the tip of shell 4 so as to form an extension of sole 5 which is below shell 4, and is preferably made in a single piece with the rest of shell 4 during the injection moulding process of the latter.

Preferably, though not necessarily, shell 4 is also provided with a transversal stiffening bar 11 made of metal material and which extends coaxial to a reference axis which is locally substantially perpendicular to the center line plane of the boot. This bar is also embedded within the protruding appendix 9 of shell 4 so that the two axial ends of the bar come out of the protruding appendix 9, at the two lateral sides 9a of the same appendix.

The upper part of shell 4 is instead preferably, though not necessarily, provided with a programmed-deformation gusseted folding 4s which extends from one side of shell 4 to the other, straddling the metatarsal area of the foot, and is structured so as to allow shell 4 to bend in the metatarsal area of the foot in order to go along with the natural bending of the foot of the user when skiing.

With reference to FIG. 1, boot 1 also comprises an inner liner 12 which is preferably made of soft and thermal insulating material, is preferably, though not necessarily, accommodated within shell 4 and cuff 7 in a removable manner, and is shaped so as to surround and protect both the foot and the lower part of the leg of the user; and a protective tongue 13 which is positioned on the upper part of shell 4, in the area above the instep and the front part of the leg, to cover the longitudinal slit of the shell (not shown), which is realized at the top ridge of shell 4, i.e. above the instep and in front of the lower part of the tibia, and which allows shell 4 to be temporarily widened in order to facilitate the insertion of the foot into liner 12.

In particular, in the example shown, the protective tongue 13 preferably, though not necessarily, consists of an oblong sheet of plastic or composite material of suitable thickness, which is substantially L-bent, and is arranged to rest on the upper part of shell 4 in the area above the instep and the front part of the leg, so as to cover the longitudinal slit of the shell (not shown).

Finally, boot 1 is provided with a number of manually-operated closing members 14 which are suitably distributed on shell 4 and on cuff 7 to straddle the protective tongue 13, and are structured so as to selectively tighten shell 4 and/or cuff 7 to stably immobilize the leg of the user inside boot 1, or better, liner 12.

With reference to FIGS. 2 and 3, unlike currently known Telemark ski boots, the duckbill-shaped protruding appendix 9 of shell 4 has, on each lateral side 9a, a respective side groove 15 that starts on the upper face of the protruding appendix 9 at a distance d₁ from the tip of the protruding appendix 9 ranging between 10 and 20 millimetres, i.e. more or less above the corresponding axial end of the transversal bar 11, if any, and then continues towards the joint between protruding appendix 9 and shell 4, progressively increasing its depth so as to form a descending slope 15a, i.e. tilted towards the sole 5 beneath, above which a respective prong 10a of the front jaw 10 of the ski fastening device 3 is adapted to be arranged.

In other words, the two side grooves 15 are realized on the two lateral sides 9a of the protruding appendix 9, in a substantially mirroring position with respect to the center line plane of the boot, so as to form two descending slopes 15a which start on the upper face of the protruding appendix 9 at a distance d₁ from the tip of the protruding appendix 9 ranging between 10 and 20 millimetres, and then flank the tip of shell 4 while progressively increasing their depth, so that each prong 10a of the front jaw 10 of the ski fastening device 3 may be arranged above a respective descending slope 15a.

Each side groove 15 is also shaped so that the descending slope 15a reaches a nominal depth h ranging between 2 and 5 millimetres, and preferably, though not necessarily, equal to about 3 millimetres, at the terminal end of the corresponding prong 10a of the front jaw 10 when the protruding appendix 9 is fitted/engaged in the front jaw 10 of the ski fastening device 3.

More in detail, each side groove 15 is shaped so that the descending slope 15a reaches a nominal depth h ranging between 2 and 5 millimetres, and preferably, though not necessarily, equal to about 3 millimetres, at a distance d₂ from the tip of the protruding appendix 9 ranging between 40 and 50 millimetres.

In the example shown, in particular, each side groove 15 of protruding appendix 9 is shaped so that the descending slope 15a starts at a distance d₁ from the tip of the protruding appendix 9 preferably, though not necessarily, equal to about 14 millimetres, and then reaches a nominal depth h preferably, though not necessarily, equal to at least 3 millimetres at a distance d₂ from the tip of the protruding appendix 9 preferably, though not necessarily, equal to about 45 millimetres.

With reference to FIG. 2, in the example shown, in particular, each side groove 15 is preferably, though not necessarily, substantially triangular in shape, and ends with a substantially vertical step 15b which is located immediately downstream of the terminal end of the corresponding prong 10a of the front jaw 10 of the toepiece of the ski fastening device 3, and at a distance d₂ from the tip of the protruding appendix 9 ranging between 40 and 50 millimetres and preferably, though not necessarily, equal to about 45 millimetres. Step 15b has a nominal height h ranging between 2 and 5 millimetres and preferably, though not necessarily, equal to about 3 millimetres.

With reference to FIGS. 2 and 3, the protruding appendix 9 of shell 4 is also preferably, though not necessarily, provided with a lower flat bevel 16 which extends on a lying plane P locally substantially perpendicular to the center line plane of the boot, and is realized on the lower face of the protruding appendix 9, between the edge of sole 5 and the end of the protruding appendix 9, so as to progressively decrease the thickness of the protruding appendix 9 towards the tip of the same appendix.

In the example shown, in particular, the lower flat bevel 16 starts close to the edge of the front sole 5, at a distance d₃ from the tip of the protruding appendix 9 preferably, though not necessarily, equal to distance d₁, i.e. immediately below the end of the transversal bar 11 if any, and ends at the tip of the protruding appendix 9, thus causing a progressive reduction k in the local thickness of the protruding appendix 9 ranging between 1 and 3 millimetres.

In particular, in the example shown, the lower flat bevel 16 starts at a distance d₃ from the tip of the protruding appendix 9 substantially equal to distance d₁, where the nominal thickness s₀ of the protruding appendix 9 is equal to about 18 millimetres, and ends at the tip of the protruding appendix 9, thus causing a reduction k in the local thickness of the protruding appendix 9 of about 2 millimetres.

Finally, with reference to FIG. 1, boot 1 is preferably, though not necessarily, also provided with a manually-operated cuff locking device 17, which arranged to straddle shell 4 and cuff 7, in the rear area 1b of boot 1 immediately above the heal, and is structured so as to be able to, on choice:

• • firmly fix cuff 7 to shell 4 so as to prevent any related movement between the two components; or
  • completely release cuff 7 from shell 4 so as to allow cuff 7 to freely oscillate about axis A both forward and backward.

Operation of boot 1 is substantially equal to that of any other currently marketed Telemark ski boot, with the difference that the presence of the side grooves 15, or better of the descending slopes 15a, and of the lower flat bevel 16 at the points of contact with the front jaw 10 of the toepiece of the ski fastening device 3, significantly modifies the kinematic interaction between boot 1 and the ski fastening device 3, thus allowing the ski fastening device 3 to also transfer the push from the skier to ski 2 in the initial part of the movement of lifting heal 6 of the boot from the ski 2 below.

The advantages associated with the particular shape of the protruding appendix 9 of shell 4 are noteworthy: a few structural modifications to the protruding appendix 9 of shell 4 allow the ski fastening devices 3 to operate in a more efficient manner, thus significantly improving the performance of the skier during Telemark skiing.

Moreover, the modifications to the structure of the protruding appendix 9 may be realized with a few modifications to the moulds for the injection moulding of shell 4, at particularly low costs.

Finally, the side grooves 15 and the lower flat bevel 16 may also be easily made on the front protruding appendixes of Telemark ski boots already marketed, with all the advantages implied.

Clearly, changes and modifications may be made to the alpine or Telemark ski boot 1 as described herein without, however, departing from the scope of the present invention.

For example, in a different embodiment (not shown), rather than consisting of a sheet of plastic or composite material with semi-rigid structure, the protective tongue 13 may be replaced by a strip of synthetic fabric of suitable thickness, possibly coupled with an impermeable film, which is fixed on the upper part of shell 4, preferably though not necessarily by gluing, in order to cover the longitudinal slit of the shell.

Claims

1. Ski boot (1) comprising a rigid shell (4) shaped so as to accommodate the foot of the user, anda rigid cuff (7) shaped so as to surround the ankle of the user and which is hinged on the shell (4) so as to be able to rotate about a first transversal reference axis (A) substantially coinciding with the articulation axis of ankle of the user;the shell (4) being inferiorly provided with a front sole (5) and a rear heel (6), and having a substantially duckbilled-shaped, front protruding appendix (9) which protrudes from the tip of the shell (4) so as to form an extension of the front sole (5), and is structured so as to couple/engage in the substantially horseshoe-shaped front jaw (10) of a specific ski fastening device (3);said ski boot (1) being characterised in that the front protruding appendix (9) has, on each side (9a), a respective side groove (15) that starts on the upper face of the front protruding appendix (9) at a distance (d1) from the tip of the protruding appendix (9) ranging between about 10 and 20 millimetres, and continues flanking the tip of the shell (4) progressively increasing its depth, so as to form a descending slope (15a) above which a corresponding prong (10a) of the front jaw (10) of the ski fastening device (3) is adapted to be arranged.

2. Ski boot according to claim 1, characterised in that each side groove (15) is also shaped so that the descending slope (15a) reaches a nominal depth (h) ranging between about 2 and 5 millimetres, at the end of the prong (10a) of the front jaw (10) of the toepiece of the ski fastening device (3).

3. Ski boot according to claim 1, characterised in that each side groove (15) is shaped so that the corresponding descending slope (15a) starts at a distance (d1) from the tip of the protruding appendix (9) equal to about 14 millimetres.

4. Ski boot according to claim 2, characterised in that said nominal depth (h) is equal to about 3 millimetres.

5. Ski boot according to claim 1, characterised in that each side groove (15) ends with a step (15b) which is located immediately downstream of the end of the corresponding prong (10a) of the front jaw (10) of the toepiece of the ski fastening device (3), at a distance (d2) from the tip of the protruding appendix (9) encompassed between about 40 and 50 millimetres; said step (15b) having a nominal height (h) ranging between about 2 and 5 millimetres.

6. Ski boot according to claim 5, characterised in that the step (15b) is located at a distance (d2) from the tip of the protruding appendix (9) equal to about 45 millimetres.

7. Ski boot according to claim 1, characterised in that the front protruding appendix (9) is also provided with a lower flat bevel (16) which extends along a lying plane (P) locally substantially perpendicular to the centre plane of the ski boot, and is realized on the lower face of the front protruding appendix (9), between the edge of the front sole (5) and the end of the protruding appendix (9).

8. Ski boot according to claim 7, characterised in that the lower flat bevel (16) starts close to the edge of the front sole (5), at a distance (d3) from the tip of the protruding appendix (9) substantially equal to the distance (d1) that separates each descending slope (15a) from the tip of the front protruding appendix (9).

9. Ski boot according to claim 8, characterised in that the lower flat bevel (16) ends at the tip of the front protruding appendix (9) causing a reduction (k) of the local thickness of the front protruding appendix (9) encompassed between about 1 and 3 millimetres.

10. Ski boot according to claim 9, characterised in that the lower flat bevel (16) ends at the tip of the front protruding appendix (9) causing a reduction (k) in the local thickness of the front protruding appendix (9) of about 2 millimetres.

11. Ski boot according to claim 1, characterised in that the shell (4) is also provided with a transversal stiffening bar (11) made of metal material, which extends coaxial to a reference axis locally substantially perpendicular to the centre plane of the ski boot, and is embedded within the front protruding appendix (9) so that the two ends of the bar come out of said front protruding appendix (9) at the two sides (9a) of the appendix.

12. Ski boot according to claim 11, characterised in that each side groove (15) having a substantially triangular profile starts substantially above a respective end of said transversal stiffening bar (11).