The invention relates to a ski binding intended for a flexible ski shoe. More specifically, the invention relates to a ski binding intended for attachment of a ski shoe having a shoe tip that is flexible in the longitudinal direction and equipped with a transverse rod or locking pin at the front part of the shoe tip, and which is somewhat wider than the shoe tip such that the locking pin protrudes some way on each side of the shoe tip. The ski binding is suitable for cross-county skiing, classic style, skating/freestyle, touring and telemark skiing.

Background of the invention

The inventor of this invention has previously developed a new type of sole for a ski shoe which allows the skier to utilise the foot' s natural movement on push-off or kick without compromising his steering ability and control of the skis. The ski shoe sole is described in WO 2013/008079.

This ski shoe sole is characterised in that it uses carbon and/or glass fibre layers to give the sole the necessary mechanical properties in the longitudinal and transverse direction, and the required torsional rigidity, and in that the attachment portion to the ski binding is configured as a plate-like flat tip with a transverse elevation at the very front part of the sole tip, as illustrated in Figures 5 a) and 5 b), which are a facsimile of Figures 2 and 3 in WO 2013/008079. The figures show a ski shoe 1 1 with a fibre sole 12. The sole' s attachment area to the binding is indicated by the reference numeral 20 and consists of a flat plate-like part 21 which protrudes in front of the ski shoe 11 and which has a transverse extension 15 that has a markedly larger thickness and a slightly larger width than the part 21, such that it protrudes on both sides of the plate-like part 21 and forms a hammer head-like profile.

In an exemplary embodiment of this sole construction, the transverse extension 15 consists of a cylindrical metal rod and the fibre layers in the forward part of the sole 12 are folded around and envelope the metal rod as is indicated in Figure 5 a). In this embodiment it is the "inner" part of the metal rod 15 that is enveloped. The "hammer head projections" on the sides are bare, i.e., the metal is exposed there. Experience has shown that this construction is very robust and wear resistant, in particular if the shoe sole is allowed to rotate about the centre axis of the metal rod 15 in the last stage of the kick.

The present invention is a ski binding that is suitable for this type of ski shoe sole and which allows rotation of the ski shoe sole over the centre axis of the front locking pin. It will be appreciated that the ski binding is not inseparably bound to this exemplary embodiment of a ski shoe sole. The present invention will be suitable for any ski sole construction which has a plate-like front portion that is flexible in the longitudinal direction and has a transverse locking pin that forms a similar hammer head profile.

Prior art

From FR 2 577 428 is known a ski binding intended for randonee skiing where the ski sole 15 has a dovetail- shaped projection 17 with transverse projecting parts 18 that fit into a groove in a stirrup 9 pivotally attached to the ski via a transverse shaft 11 through the upper part of the ski. After the projecting parts 18 have been placed in the groove in the stirrup 9, the ski sole can be locked to the stirrup 9 by means of a pivotal locking mechanism 20, 21 that clamps the projection 17 down against the stirrup 9 as illustrated in Figures 4 and 5 in the document. The ski shoe is thus pivotally attached to the ski in that the whole ski binding and shoe rotate over the transverse shaft 11 , as shown in Figure 6 in the document.

US 4 613 150 refers to a ski binding intended for cross-country skiing. This binding is designed for attachment of a ski sole that has a plate-like projection 6 with a transverse rod or locking pin 7, both parts are made of metal. The ski binding consists of a rectangular block 11 with an impressed T-shaped groove intended for receiving the projection 6 with locking pin 7. The T-shaped groove is formed by making a transverse linear recess 12 and a rectangular recess 13 in the block 11. The outer ends of the locking pin 7 will enter into a transverse groove 12 in the block 11 when the ski shoe tip is inserted into the T-shaped groove. Inside the rectangular block 11 lies a U-shaped metal rod 28 that is slidable back and forth inside the block such that the ends of the metal rod 28 will project from the block 11 above the ends 7 of the locking pins down in the groove 12 and form an overlying barrier such that the locking pin cannot come out of the groove 12. See Figure 2 in US 4 613 150. The metal rod 28 is pushed back and forth with the aid of a spring-tensioned locking mechanism 18, 19, 22 placed at the front end of the block 11.

WO 2013/008079 refers to a ski binding comprising a base plate 31 which, together with a substantially laterally oriented side wall 33 on each side of the base plate and a front transverse wall 24, forms a guide channel 22 for receiving the plate-like flat tip 21 of a ski shoe sole of the type shown in Figures 5 a) and 5 b) in the present application. In an embodiment intended for the "hammer head variants" of the ski shoe sole, the side walls 33 of the ski binding are equipped with transverse slots 32 for receiving the "projection" of the transverse extension 15. Attachment of the ski shoe sole to the binding is obtained in that a transverse clamping bar 27 is pressed down against the extension 15 along the whole width of the extension, clamps it down against the base plate 31 and locks the "projections" in the slots 32. Object of the invention

It is an object of the invention to provide a ski binding that can be used with a low- profile sole and shoe, where the whole structure is minimally exposed to icing and that it is easy to get to and thus remove snow and ice, which may nevertheless have become lodged in the binding.

It is a further object of the invention that the binding' s fastening device should not come into contact with the side walls of the ski track, which would give a braking effect.

Similarly, it is an object of the invention to provide a ski shoe sole and a ski binding that provide a robust and reliable connection between ski binding and ski shoe sole.

It is also an object of the invention to reduce the weight of the ski binding and ski shoe.

Description of the invention

The objects of the invention are achieved with a ski binding according to claim 1. Additional embodiments of the invention are defined in dependent claims 2- 10.

Compared to the ski binding referred to in WO 2013/008079, the attachment principles are substantially changed, in that there is a departure from the principle of clamping the shoe tip in place in the binding for a hold/lock principle on the ends of the attachment bar, thereby being able to maintain a rotation of the ski shoe on completed kick or push-off. This gives less stress on the fibres in the shoe sole, and will thus be able to prevent any cracks or breaks on long-term use.

The operating mechanism of the binding is new and very robust, such that it no longer needs to be operated manually, but can easily be operated by the foot/skis or using the ski poles, even in an upright position, which makes entering and exiting the binding much easier, as it can be done without having to bend down. This new method can be compared with the standardised and problem-free way in which a slalom ski binding is entered and exited.

These objects are solved by a ski binding according to claim 1. Additional embodiments of the invention are defined in dependent claims 2- 10.

The innovation of the invention gives the ski binding a weight reduction in the range of from 10 to 40 %, compared with today' s known commercial solutions.

The present invention provides options for a laterally and torsionally steady and stable attachment of a ski shoe to the ski, where the ski shoe has a sole that is almost as flexible in the longitudinal direction as a running shoe in the toe portion and the metatarsal region of the sole. Ergo, a far more effective push-off is achieved that engages the calf muscles fully, but which at the same time gives sufficient torsional and transverse stability to give the skier good control of the skis under all conditions and in particular on downhill slopes. The present invention also means that the binding' s fastening device preferably lies in front of the toes and holds the sole in place against the ski, such that the foot will always press against the surface throughout the execution of a push-off. The invention' s combined design of sole and binding ensures that the foot always presses down against the ski throughout the push-off phase, which permits a more powerful and more effective push-off.

Altogether, the changes in the description make a more robust and simple

connection between the ski shoe, ski and ski binding, where also the possibility of fatigue fractures is reduced to a minimum without reducing the sole' s flexibility in the longitudinal direction and rigidity in the transverse direction.

The ski binding according to the invention can advantageously be integrated with a ski plate which will lie between the binding and the ski. An object of the ski plate is to permit a releasable attachment of the binding without screwing screws or in some other way engaging in the ski itself. Another object is to give the end user a more flexible solution in that the ski binding can easily be transferred from one pair of skis to another. A further object is to form an "add-on layer" on the ski that lifts the ski binding and the ski shoe a little way above the ski. This can be especially advantageous when the ski binding is used together with ski shoes of the type referred to in WO 2013/008079, as these ski shoes have a very low profile which follows the flat sole (lacks relatively thick longitudinal ribs/grooves under the sole like those that today' s commercial cross-country ski shoes have), which can easily result in the ski shoe butting against the edge of the ski track.

In an alternative embodiment, the binding can be included in a new fastening system against a fixed flat ski plate that is fastened to the ski in that the underside of the binding' s base plate is provided with a groove complementary to a groove in the ski plate which allows an attachment of the ski binding to the ski plate in several positions with the aid of the complementary grooves and a stop screw that locks the binding to the ski plate without any screws entering into the ski. The groove on the underside of the ski binding can advantageously be configured to form a tongue and groove type connection with the groove in the ski plate that is fastened to the ski. The underside of the ski plate, i.e., the side facing down towards the ski, may be flat and have no grooves, and will thus be suitable for all types of skis. Alternatively, the underside of the ski plate can be configured such that it will grip and hold securely fast to existing solutions for ski plates that are often supplied ready mounted on the skis from the ski factory when they are delivered to sales outlets. In another alternative, it is only possible to use one or more grooves that are

complementary to the grooves on the underside of the ski binding base plate without a ski plate. In this case, the one or more grooves will be fastened directly on the ski by gluing, screwing or in some other suitable manner. The height that this fastening system builds above the ski allows a somewhat wider binding platform because it comes higher up in the standardised ski track, and it gives a larger contact face between binding and shoe, which will give better stability during the execution of the push-off. List of figures

The scope and nature of the invention will now be described in more detail with reference to the attached drawings, wherein:

Fig. 1 illustrates a ski binding according to an exemplary embodiment of the invention with overlying bar and locking groove seen in perspective in the closed state.

Fig. 2 illustrates a ski binding according to a first exemplary embodiment of the invention with overlying bar seen from the side in the closed state.

Fig. 3 illustrates a ski binding according to a first exemplary embodiment of the invention with overlying bar and locking groove seen in perspective in the open state.

Fig. 4 a) illustrates the ski binding shown in Figures 1 - 3 when it has been released from the ski plate.

Fig. 4b) illustrates schematically the tongue and groove connection of the ski plate and the ski binding according to a first exemplary embodiment of the invention. Fig. 4 c) illustrates schematically the same connection as in Fig. 4 b), but for the exemplary embodiment where the grooves are fastened directly on the ski.

Figs. 5 a) and b) are a facsimile of Figures 2 and 3 in WO 2013/008079 and illustrate an example of a ski shoe sole suitable for use together with the present invention.

Fig. 6 a) illustrates a ski binding according to a second exemplary embodiment of the invention seen in perspective in the closed state.

Fig. 6 b) illustrates the same exemplary embodiment as Figure 6 a), but now seen from immediately above.

Fig. 6 c) illustrates the same exemplary embodiment of the ski binding as in Figure 6 a) in the closed state.

Fig. 6 d) illustrates the same exemplary embodiment as Figure 6 c), but now seen from immediately above.

Fig. 7 a) illustrates a cross-sectional full side view of the same exemplary embodiment as Figures 6 a) and 6 b) along the axis A - A shown in Figure 6 b). Fig. 7 b) illustrates a cross-sectional full side view of the same exemplary embodiment as in Figure 6 c) and 6 d) along the axis A - A shown in Figure 6 d). Exemplary embodiments of the invention

The invention will now be described in greater detail with reference to Figures 1 to 4 c) and 6 a) to 7b), which illustrate exemplary embodiments of the invention adapted to be integrated with a ski plate that is to be fastened to the ski. These exemplary embodiments should not be understood as a limitation of the scope of the invention, as embodiments are also conceivable where the binding is fastened directly onto the ski by screwing, gluing or in some other suitable manner.

Reference is made to Figure 1 which shows an exemplary embodiment of a ski binding with a fastening device which in its entirety is positioned in front of the toes. The ski binding according to this exemplary embodiment consists typically of two components: a base structure and an overlying bar (1), which may have a protrusion as shown in Fig. 1 or be a rod-shaped body etc. These parts can be constructed of any suitable metal, plastic or composite material. Examples of suitable materials include, but are not limited to, aluminium, carbon fibre plastic, polycarbonate, polyoxymethylene (POM), polyethylene terephthalate (PET).

As illustrated in Figures 1 to 3, the base structure of the binding comprises a base plate (14) with a front wall (8) and two side walls (5) that project up from the binding base plate (14) and enclose a surface/area that constitutes a guide channel (2) on the upper side of the base plate (14). The guide channel (2) will receive the plate-like front portion of the ski shoe sole and should thus be given a shape complementary to the plate-like front portion to ensure that the front portion of the ski shoe sole cannot be displaced sideways relative to the ski binding. Apart from this, there are no limitations to the shape of the guide channel (2), it may be conical, parallel or have any other complementary shape to the front portion of the ski shoe sole.

The side walls (5) have a transverse recess (9) which ends in a lower groove (7) intended for receiving the end pieces ("projections") of the ski shoe sole locking pin. When these "projections" of the ski shoe sole locking pin have been placed in the side grooves (7), the grooves (7) will ensure that the ski shoe sole is prevented from being displaced forwards or backwards relative to the ski binding.

The front part, i.e., the part of the side wall (5) that is in front of the recess (9), has a throughgoing opening in the longitudinal direction and forms a housing (11) for receiving a torque arm (4). The torque arm is fastened pivotally via a transverse pivot 15 to the housing (1 1) as is indicated in broken lines in Figure 2, and is given a shape and a length such that it will always project some way out from the housing (11) in the forward direction (towards the ski tip) regardless of whether the ski binding is in the locked or open state. The torque arms (4) in each side wall (5) are connected to each other by means of a transverse bar (1) at the front end of the torque arms as illustrated in Figures 1 and 3, which show the binding in respectively the open and the closed state. At the rear end, i.e., the end pointing towards the ski shoe, the torque arm (4) is given a length and configuration such that it will alternate between being withdrawn into the housing (11) when the binding is in the open state (see Figure 3), and projecting out of the housing and pressing down against the groove (7) (as shown in Figures 2 and 3) when the binding is in the locked state. Opening and locking of the binding is thus achieved by rotating the torque arms (4) by pushing the bar (1) forwards and backwards between the positions shown in respectively Figure 1 and Figure 3. The ski shoe sole locking pin, in this exemplary embodiment, will be secured/fastened to the groove (7) by means of the end pieces of the torque arms (4) which come out of the forward part of the binding housing (11) and grip about and secure the locking pin' s "projections" when the overlying bar (1) is lifted up against the front wall (8), as shown in Figure 1 and Figure 2 (the figures do not show the locking pin or other parts of the ski shoe/ski sole). The edges of the side walls (5) are so high that they provide a lateral support to the attachment of the sole when push-off has been completed. This contributes to a robust connection between sole and binding.

Reference is now made to Figure 3 where the overlying bar (1) is shown in the open position, whereby the cooperating torque arms (4) are withdrawn into the ski binding housing (11). In this open position, the "hammer head projections" of the ski shoe sole (the ends of the locking pin) are lowered into the locking groove (7) and supported by both the guide channel (2) and the guiding edges (5). As mentioned above, moving the bar (1) up from the ski will cause the torque arms (4) to rotate such that their rear ends come out of the housing and press down against the end pieces of the ski shoe sole locking pin, as shown in Figures 1 and 2. By equipping the front wall (8) with an elevated portion of adapted height such that the end edge of this portion will come into engagement with the overlying bar (1) when lifted into the locking position (see Figure 1) and butt against the bar with a suitable tension, it is possible, by including a recess (10) in the upper end of the front wall (8), to obtain that the tension in the bar (1) locks it securely to the recess (10) with a "click". This is a very simple and robust self-locking mechanism that can be opened and closed by means of skis, poles or shoes without bending down.

The ski binding can advantageously include an elastic body on the rear of the front wall (8), i.e., be positioned such that the body will be compressed between the front wall (8) of the ski binding and the ski shoe tip when the skier is in the final phase of a push-off and lifts the ski in order to move the foot forwards to the next push-off. This will give enhanced control of the ski during this part of the push-off or kick.

The tolerance of the distance between the binding' s guide channel (2) and the complementary shape of the sole tip is preferably between 0.01mm and 3mm.

An exemplary embodiment of the ski binding according to the invention is intended to be fastened to a ski plate (3) which is attached to the ski, preferably by gluing or in some other manner that does not include screwing screws into the ski. The ski binding according to the exemplary embodiment will thus obtain advantages in that the binding can easily be replaced or transferred to another ski with corresponding ski plate (3), and in that the thickness of the ski plate (3) lifts the binding and the ski shoe up from the upper side of the ski.

Reference is made to Figure 4 a). The figure shows a ski binding with base plate (14) which, on its underside, has two "female grooves" (12) and a ski plate (3) with two "male grooves" (13) having a complementary shape such that they can be passed into each other and form a tongue and groove type connection. The ski binding base plate (14) has a depression or recess (6) that is throughgoing in the longitudinal direction and passes through the ski binding base plate (14) to receive a screw where the head is sunk into the base plate and where the position of the screw can be changed in the longitudinal direction to vary the ski binding' s attachment relative to the ski plate (3) or the ski. Similarly, there is a threaded hole (16) in the ski plate (3) for receiving the fixing screw. This hole can advantageously not be throughgoing such that the screw will not penetrate down into the ski. This permits shop mounting without drilling into the ski, and allows adjustment of the ski binding' s position in the longitudinal direction as desired by the skier without having to drill.

Figure 4 b) is a schematic side view of an example of the complementary shape of the grooves (12, 13) for forming a tongue and groove type connection of the binding to the ski plate. The recess (6) and the threaded groove (16) are illustrated in broken lines in the figure.

The recess for screw (6) in the guide channel (2) is, in this exemplary embodiment, constructed for a locking screw to fasten a ski binding to the ski plate (3). Any other way of fastening the ski binding to the ski plate (3) can also be utilised.

In another exemplary embodiment, it is possible to use only the groove (13) without using a ski plate (3). In this case, the groove (13) is fastened directly to the ski by gluing, screwing or in some other suitable manner. This exemplary embodiment is illustrated schematically in Figure 4 c). The figure illustrates the fastening of the groove 13 on the upper side of the ski (not shown) by means of one or more screws (23). Other attachment methods are also conceivable, either alone or in combination with the screws.

A second exemplary embodiment of the ski binding has the same basic structure as the first exemplary embodiment in that it uses the same base plate (14) with the same guide channel (2) and side walls (5) with a transverse recess (9) that ends in a lower groove (7) intended for receiving the end pieces (the "projections") of the ski shoe sole locking pin. In the same way as in the first exemplary embodiment, the part of the side wall (5) that is in front of the recess (9) has a throughgoing opening in the longitudinal direction for receiving a torque arm (4). The torque arm is fastened pivotally via a transverse pivot to the housing (11) as indicated in broken lines in Figures 7 a) and 7 b), and is given a shape and a length such that it will always project some way out of the housing (1 1) in a forward direction (towards the ski tip) regardless of whether the ski binding is in the locked or open state. The torque arms (4) in each side wall (5) are connected to each other by means of a transverse bar (1) at the forward end of the torque arms.

What distinguishes the second exemplary embodiment from the first is that the bar (1) in the second exemplary embodiment is a rod-shaped body with cylindrical symmetry and further that the front part of the side walls (5) extends forwards along the whole periphery of the front part of the base plate (14) until they meet and are integrated in each other and that the front wall (8), together with the side walls (5), forms a housing (1 1) that surrounds the whole of the front part of the binding base plate and "closes in" the locking mechanism in order to protect it from snow and any debris lying in the ski tracks. Further, in the second exemplary embodiment a cover (18) is fastened pivotally via a pivot (21) to the ski binding' s side walls (5) at the very front edge of the ski binding.

The second exemplary embodiment is illustrated in Figures 6 a) to 7b). Figures 6 a) and 6 b) show the binding in the closed position, seen respectively obliquely from above and immediately from above. Figure 7 a) shows a cross-section of the binding seen in full side view along the plane indicated in the broken line designated A - A in Figure 6 b). Figures 6 c) and 6 d) show the binding in the open position, seen respectively obliquely from above and immediately from above. Figure 7 b) shows a cross-section of the binding seen in full side view along the plane indicated in the broken line designated A - A in Figure 6 d).

In Figures 6 a) and 6 b) the cover (18) is closed. In this position, the torque arm (4) has been rotated such that it projects from an, in the longitudinal direction, through- going opening (17) in the housing (11) and presses down against a lower transverse groove (7) in the transverse slot (9), and will fasten a locking pin that has been placed into the groove (7) in exactly the same way as in the first exemplary embodiment shown in Figures 1 to 3. In Figures 6 c) and 6 d), the cover (18) has been put in the open position. In this position, the torque arm (4) has been rotated so as to draw it into the longitudinal opening (17), thereby enabling a locking pin in the groove (7) to be freely lifted up.

As in the first exemplary embodiment referred to above, this exemplary

embodiment also comprises a torque arm (4) in each side wall (5) that is fastened pivotally via a transverse pivot (15) to the housing (11) and given a shape and a length such that it will always project some way out of the housing (11) in the forward direction (towards the ski tip) regardless of whether the ski binding is in the locked or open state. The torque arms (4) in each side wall (5) are connected to each other by means of a transverse bar (1) at the front end of the torque arms, which is not shown in Figures 6 a) to 6 d) as this part of the binding' s locking mechanism lies inside the housing (11). Figure 6 c) shows, however, that the mechanical connection between the torque arm (4) and the cover (18) comprises an underlying (pointing down towards the base plate (14)) fastening device (19) and a torque transfer arm (20) which at one end is pivotally fastened to the cover' s locking attachment device (19). At the second end, the torque transfer arm (20) is pivotally fastened to the transverse bar (1), which also cannot be seen from Figures 6 a) to 6 d) as this part of the locking mechanism, too, lies inside the housing (1 1).

Figure 7 a) shows the ski binding according to the second exemplary embodiment in closed position in full side view over a vertical cross-section along the broken line shown in Figure 6 b) to illustrate the closing mechanism in greater detail. In this position, the binding is closed in that the cover (18) has been rotated over the shaft (21) such that it butts against the housing (11) (the figure shows only the upper part, the "roof of the housing). In this position, the shaft (22) via which the torque transfer arm (20) is pivotally fastened to the cover's locking attachment device (19) is located such that the torque transfer arm (20) has rotated the torque arm (4) via shaft (15) such that its projection projects from the longitudinal opening (17) (not shown) in the housing and presses down against the groove (7). The torque transfer arm (20) is pivotally fastened to the torque arm (4) at the shaft/bar (1). The length between shaft (22) and (1) on the torque transfer arm (20) can advantageously be adapted such that when the cover is in this position, a tension is obtained that locks it in place butting down against the "roof of the housing (11).

Figure 7 b) shows the same cross-section as in Figure 7 a) in the open position. In this figure it can be seen that now the cover' s locking attachment device (19) has drawn the torque transfer arm (20) forwards such that the torque arm (4) is rotated back inside the longitudinal opening (17) (not shown) in the housing (1 1).

The second exemplary embodiment is illustrated in Figures 6 a) to 7 b) with two parallel torque transfer arms (20) and two locking attachment devices (19). This should not be interpreted as obligatory for the invention. Embodiments are conceivable which utilise only one torque transfer arm (20) and one locking attachment device (19), or three or more torque transfer arms (20) and three locking attachment devices (19).