EP0411478B1 - Ski with a holding plate for holding the ski binding - Google Patents

Abstract

In order to avoid stiffening of a downhill ski due to the ski boot and the ski binding in the binding region, the binding is mounted by means of spacers (17) on a thin metal plate (3) which is provided separately in the ski and which is mounted on the ski core (1) so that it floats in the ski via interposed thin layers of rubber (11, 12). The spacers (17) hold the binding elements (8) with spacing from the surface of the ski and do not transfer forces from the torsional frame (2) of the ski onto the binding and vice-versa. <IMAGE>

Description

The invention relates to a ski with a core made of light material, such as. As poplar wood, fir wood or foam plastic, with upper and lower layers of high-strength material, such as z. B. fiber-reinforced epoxy resin and / or light metal, which are preferably combined to form a torsion box surrounding the core, and with a parallel to the top of the ski essentially only in the binding area extending holding plate assembly into which holes can be made for receiving screws, which the heel and can bind the tip of the ski boot holding parts with the ski, the holding plate arrangement inside the ski body via elastomeric intermediate layers, such as. B. rubber or silicone rubber is stored, which are integrally (so firmly adhering, z. B. by gluing) connected to both the mounting plate assembly and the ski body.

In conventional skis, in which the normally two-part binding holds both the heel and the tip of the ski boot, as is the case above all with so-called alpine skis or skis for downhill skiing, there is a major problem in that the screws that hold the binding hold, must be firmly anchored in the ski body and therefore find their hold in the ski body primarily in the upper layer made of high-strength material. As a result, the corresponding binding parts and the ski boot are connected to the ski to form a rigid unit. This robs the ski of its original elasticity in its central area and makes it stiffer than is desired.

This undesirable effect also occurs with another type of ski, in which a retaining plate in the ski core (AT-B-214 326) or between the ski core and the upper part extends sideways over the majority of the width of the ski core and in the longitudinal direction of the ski over the length of the binding region high-strength layer (US-A-3 635 482) is arranged. The sheet lies directly on the material of the core or the high-strength layer. It is used to hold the screws that hold the binding. When the binding is installed, the screws tighten the upper one high-strength layer firmly to the binding, so that the original elasticity of the ski center is lost here too. The bracket itself also has a stiffening effect.

The same effects occur with another known ski (CH-A5-575 768), in which narrow aluminum sheet strips extend in the longitudinal direction of the ski in grooves on the core top side, which abut the upper high-strength layer at the top. The metal strips are also used to hold the screws holding the binding.

In another known construction (FR-A1-2 431 868), a flat frame-like insert extends in the middle of the ski height in the binding area, from which threaded bushes protrude to the ski surface and serve to receive the screws holding the binding. Instead of the threaded bushes, pins can also protrude from the insert, which carry heads at a distance from the ski surface.

Appropriate recess-bearing base plates of the binding are then to be pushed and locked under these heads. Here, too, the binding and thus the boot are firmly clamped against the ski by the heads of the screws or pins, whereby the original elasticity of the ski center is lost. The predetermined position of the pins or threaded bushings also limits the ski to a specific type of binding.

The disadvantageous stiffening in the binding area is avoided in the construction according to EP-A2-0 354 379, which belongs to the prior art in accordance with Article 54, Paragraph 3 EPC. In this case, the fastening screws, which hold the two binding parts at a distance from the ski via spacer elements, can be screwed into two narrow metal strips, each of which is embedded in an elastomer block that runs in a groove in the ski core. With this construction, the ski can spring well regardless of the ski boot and binding, since the elastomer blocks are large. However, this construction also offers technical problems.

The grooves with a large cross-section affect the strength of the ski body.

Furthermore, the holding plates in the ski are not only movable in the longitudinal direction of the ski as desired, but also to a certain extent in the transverse direction of the ski.

The invention solves the problem of creating a new type of ski which has the advantages of the construction described above without the disadvantages thereof, that is to say a ski in which the binding can be fastened without disturbing weakening of the ski core in such a way that neither the binding nor the ski boot is one has a significantly stiffening effect on the binding area of the ski. The binding should be connectable to the ski with little effort. Furthermore, and this is essential, the connection of the binding parts to the ski should be such that the flexibility of the connection exists only in the longitudinal direction of the ski, but not in the transverse direction of the ski. This leads to optimal guidance. Finally, the entire binding area should be suitable for receiving the screws for holding the binding.

The invention solves the stated problem by the training according to claim 1.

The plate is preferably formed from an aluminum sheet. A thickness of approximately 1 mm has proven itself for this. The plate can also consist of a high-quality fiber-reinforced plastic material, or also be a composite panel made of at least one thin metal layer and optionally fiber-reinforced plastic.

Characterized in that the holding plate above and below, i.e. with its two large surfaces via thin elastomer layers cohesively connected to the ski body, the shifts required for deflection or spring deflection of the ski between plate parts and corresponding parts of the ski body take place with deformation of the elastomer layers without that the stiffening forces of the binding and the ski boot significantly counteract this. The large-area connection between the holding plate and the ski body over the entire binding length ensures perfect lateral guidance of the ski through the binding.

The elastomer layers will usually be rubber layers. The elastomer layers can advantageously have thicknesses on the order of 0.5 to 1 mm. You should be highly elastic, such as. B. the rubber of the tread of motor vehicles.

In order to guide the plate laterally in the ski body particularly firmly, the side edges of the plate can lie directly against the side walls of the fiber-reinforced plastic torsion box, which surrounds the ski core, which is made of wood, for example. The plate can be supported laterally against the torsion box or corresponding other fixed parts of the ski body, but also via narrow elastomer strips. These elastomer strips, which are then advantageously integrally connected to the upper and lower elastomer layer, allow a longitudinal displacement between the ski body and the plate, but counteract a transverse displacement between the ski body and the plate.

The fact that the plate extends in the longitudinal direction of the ski only under the binding area, ie only as far beyond the screw-in points in question for the binding forward and backward as this to hold the screws even the longest binding is necessary, it has no disruptive influence on the other parts of the ski.

As a rule, the length of the plate for a ski of customary length will be around 60 cm.

The invention allows the holding plate with its elastomer layers between the small thickness of the holding plate and elastomer layers, which together in practice will not be much thicker than about 2 mm, without or almost without weakening the core or increasing the ski in the binding area Arrange the core and the upper high-strength layer.

A ski that is provided with a plate for receiving the binding fastening screws in the manner described can easily be provided with a binding. For this purpose, when drilling the holes for receiving the fastening screws, these holes are drilled wider in the upper area, so that the plate is exposed upwards. Then it is sufficient if the binding parts are supported directly or indirectly on the plate when fastening by means of the screws.

Accordingly, a ski with screwed-on binding parts according to the invention is characterized in that the binding parts are screwed against the plate by means of spacers extending through recesses in the upper layer of high-strength material. Since the spacers in the recesses of the upper, high-strength layer can shift towards the latter, the ski boot with the binding and the plate can form a relatively rigid body, which is guided in the ski in a flexible manner via the elastomer layers surrounding the plate, without the ski bending to significantly influence the rigidity of the plate, the ski boot and the binding.

The binding parts must therefore not clamp the upper, high-strength layer between themselves and the plate. So you should sort of like resting on the pillars on low columns, which protrude through the high-strength layer with air. The binding parts can be flat sheets in the usual way. These can be used as "supporting pillars" with downwardly pressed bowls which have through holes for the screws in the middle. However, a construction is preferred in which the spacer elements are formed by flat washers in the manner of washers, which surround the screws and are so thick that there is still a slight amount of air between the surface of the ski and the binding parts. The spacer elements can hold the binding parts, for example, at a distance of a few tenths of a millimeter from the ski surface.

The front and rear end faces of the plate should lie opposite the most flexible parts of the ski body, for example corresponding end faces of the wood or foam core. Small cavities can also be provided here. These can be kept free in the manufacture of skis, for example, by gluing small foam cords with a cross section of, for example, one square millimeter to the front and rear end faces of the plate or partial plate before the ski is manufactured. However, the front and rear end faces of the plate or partial plate are preferably supported against the ski body via volume-variable elastomer parts. This is in turn preferably effected in that the elastomer layers covering the plate at the top and bottom are simply brought together here without the front and rear edges of the plate being sharpened accordingly. This creates small voids here. These are already sufficient to absorb the slight displacements that occur when the ski bends without correspondingly changing the length of the plate.

An exemplary embodiment for alpine skis designed according to the invention is described below with reference to the drawings.

Fig. 1 shows the top view of a ski according to the invention.

FIG. 2 shows the section II-II from FIG. 1 on an enlarged scale.

FIG. 3 shows the section III-III from FIG. 2 on an even larger scale.

The ski shown has a wooden core 1, which is surrounded in the usual way by a torsion box 2, which consists of a fiber-reinforced layer of epoxy resin. The upper and lower walls of the torsion box form the upper and lower layers of high-strength material. Under the upper wall of the torsion box 2 runs a thin light metal layer 3 reinforcing this wall, which is not shown in FIG. 2 for the sake of simplicity. The ski is surrounded on the outside by a cover layer 4. At the bottom he has an outsole 5 and steel edges 6. The base plates 8 of the automatic heel unit and the front jaw of the ski binding, which are only shown schematically, are fastened to the top of the ski body by means of screws 7. Otherwise the ski binding is not shown.

As far as previously explained in the description of the example, the structure of the ski is known.

According to the invention, an aluminum plate 10 extends below the light metal layer 3 belonging to the upper side of the torsion box 2 and, as can be seen from FIGS. 2 and 3, is covered at the top and bottom by rubber layers 11 and 12. The rubber layers 11 and 12 extend over the entire width of the ski and are integrally connected to the aluminum sheet 3 and the aluminum plate 10 or the wooden core 1 and the aluminum plate 10, for example by vulcanization or by gluing with hardened epoxy resin. As can be seen from Fig. 3, which shows only one half of the cross section of the ski, both rubber layers extend over the full width of the ski kerus 1. As can be seen from Fig. 2, the upper rubber layer 12 extends forwards and backwards somewhat over the Length of the aluminum plate 10. Extends further to the front and rear, the lower rubber layer 11, which extends in the manner shown in FIG. 2 at the front and rear end in the recess of the wooden ski core 1 receiving the two rubber layers and the aluminum plate 10 up to the surface of the core. This recess can be made in a simple manner by milling. As can best be seen in FIG. 2, the invention allows a very flat cutout to be used, so that the bending behavior of the ski is only slightly influenced. The ski can also be made without milling. Then the plate arrangement with its elastomer layers lies between the un weakened core and the upper layer 2. In this case, the front and rear edges of the sheet metal plate 10 and possibly also the elastomer layers can be sharpened, so that the resulting approximately 2 mm high increase in the middle of the ski their ends steadily fall down. Because the two rubber layers, as can be seen in FIG. 2, extend beyond the blunt front and rear ends of the aluminum plate 10, they enclose small air spaces between them and the aluminum plate, which are not completely filled with adhesive even when the ski is pressed. This allows the front and rear ends of the aluminum plate 10 to move relative to the ski if this becomes necessary when the ski bends.

The aluminum plate 10 is supported on the sides against the side walls of the torsion box 4 by means of narrow elastomer strips, as can best be seen from FIG. 3. The side walls of the aluminum plate are also blunt, as can also be seen in FIG. 3. However, the aluminum plate 10 can also extend up to the side walls of the torsion box 2, or, if this is not present, up to the side covering of the ski body.

In the form described so far, but of course without the plates 8 and the screws 7 representing the binding parts, the ski comes on the market. Usually, it is only the binding that is provided by the dealer. For this purpose, four screw holes are drilled through to the aluminum plate 10 for each of the two plates 8 in the exemplary embodiment. For drilling the screw holes, a drill with a countersink is used, which at the same time as drilling the threaded hole for the screw in the sheet 10 has an enlarged hole 16 through it upper high-strength layer 2 and the upper rubber layer 12 countersinks down to the upper surface of the aluminum plate 10.

To fasten the binding, the binding parts 8 are then screwed to the aluminum sheet 10 with the aid of washers 17 shown exaggeratedly high in FIG. 3 and the screws 7. The washers 17 are so high that they carry the binding plates 8 at a short distance from the surface of the upper cover layer 4. In this way, as can best be seen from Fig. 2, the bond through the high-strength upper layer of the torsion box is directly connected to the aluminum plate 10, without the binding being able to exert disruptive forces on the upper high-strength layer of the torsion box when the ski springs through . If the aluminum plate 10 is guided directly on the side walls of the torsion box 2, the lateral end face of the aluminum plate 10 can be coated with a separating agent before the ski body is pressed in, so that it is not connected to the torsion box 2 in a materially integral manner.

It can be seen from FIG. 2 that when the binding area springs down, the top of the torsion box 2 is shortened without the holding of the binding with the aluminum plate 10 substantially counteracting such a shortening. The air between the washers 17 and the holes in the high-strength layer 2 is sufficient for this. The resulting longitudinal differences between the aluminum plate 10 and the top of the torsion box 2 are absorbed by corresponding shear deformations of the upper rubber layer 12. The same applies to relative changes in length between the ski core and the aluminum plate 10.

Claims (6)

1. Ski comprising a core (1) of light material
having upper and lower layers (2) of high-strength material connected in material-locking manner to the core,
and a holding plate (10) which extends parallel to the ski upper side substantially only beneath the binding and into which holes can be introduced for receiving screws (7) which can connect binding members (8) holding the heel and the toe of the ski boot to the ski,
the holding plate (10) being mounted in the ski body via elastomeric intermediate layers (11, 12) which are connected in material-locking manner both to the holding plate and to the ski body,
characterized in that
the holding plate (10) is a thin plate,
the holding plate (10) and the elastomeric intermediate layers (11, 12) extend sidewards substantially over the entire width of the ski core (1) and in the ski longitudinal direction over the entire length of the binding region,
and the holding plate (10) and the elastomeric layers (11, 12) lying between the upper high-strength layer (2) and the holding plate (10) and between the core (1) and the holding plate (10) form a layer thin compared with the height of the ski core.

2. Ski according to claim 1, in which the upper and the lower high-strength layers are connected by high-strength side layers to form a torsion-stiff hollow box surrounding the core,
characterized in that
the holding plate is supported laterally against the side layers of the torsion box.

3. Ski according to claims 1 or 2,
characterized in that
the holding plate (10) extends between the ski core (1) and the upper high-strength layer (2).

4. Ski according to claims 1, 2 or 3,
characterized in that
the holding plate consists of one piece.

5. Ski according to any one of claims 1 to 4,
characterized in that
the thickness of the holding plate and that of the two elastomeric intermediate layers are each of the order of magnitude of 1 mm.

6. Ski with screwed-on binding according to any one of claims 1 to 5,
characterized in that
the screws holding the binding parts extend through spacer elements supported against the holding plate,
that the spacer elements hold the binding parts a slight distance from the ski surface,
and that the cutouts provided in the upper high-strength layers of the ski for the spacer elements surround the latter with clearance.

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