EP0993325B1 - Planks used for sliding on snow - Google Patents

Abstract

The invention relates to planks used for sliding on snow, having a central part (1) situated between a lower and upper flange. The central part (1) contains areas (11, 13) made of light materials and areas (12.1, 12.2,..., 14, 15) made of reinforcing materials. As a result, the board has the following properties: low empty weight, high transversal strength and high resistance to pressure.

Description

The invention relates to a snow sliding board and a method for the same Production according to the preambles of the independent claims.

There are different types of snow sliding boards, such as B. Alpine, cross-country, telemark or jump skis, big feet, snowboards, etc. The latter differ in their structure and use from most other snow sliding boards. Snowboards are wider than that other snow sliding boards. While most skis individually on one leg of the skier and therefore for use in pairs only one snow gliding board is needed to drive, which, unlike other snow sliding boards, has two binding attachment areas having. These binding attachment areas in turn point in contrast to other snow sliding boards, integrated shots of the Binding on, so-called inserts.

Most snow sliding boards have a proven and consistent one Building on. These are sandwich constructions, with a core load-bearing cover straps made of fiber-reinforced flexible plastic laminates is plastic coverings and side panels made of plastic or steel elements are made.

A disadvantage of known snow sliding boards is their relatively high mass density of over 900 kg / m ³ and the resulting high weight. For snowboards with typical dimensions such as 1500 mm length, 290 mm maximum width and 10 mm maximum thickness, this results in dead weights of over 3.2 kg. Such heavy snowboards are tedious to carry, they have to be driven with great effort and they are slow to react when changing direction. For this reason, snow sliding boards with a low weight are aimed for, so-called light boards or light boards.

A solution for the construction of light boards is disclosed in the patent specification CH-686 028. When using a light core with a density of not more than 400 kg / m ³ , light snowboards with average densities of at most 850 kg / m ^{3 are obtained} . Honeycomb materials or fiber-reinforced rigid foam are proposed as light core materials.

A first disadvantage of such light snow sliding boards concerns the absorption capacity of shear stresses between the outer layers and a low one Shear stiffness and the relatively poor damping behavior Vibrations and blows. Shear stresses arise, for example the bending of the snow sliding board caused by shear stress and affect its resistance to deformation or breaking and the driving properties. Vibrations and impacts come from external disruptive factors such as Uneven slopes and bumps and reduce the smoothness and the Kantensriff. Light core materials have low shear strength and a low thrust module, so that there is an imminent risk of breakage and cracking consists. Furthermore, (unreinforced) light boards dampen impacts badly from.

A second disadvantage of light snow sliding boards concerns the pressure resistance. Light core materials have a low compressive strength, they are compressible. In particular, the compressive strength of honeycomb structures is high deflection of the component is greatly reduced. As a result, it changes the distance of the straps from each other, which in turn has a negative impact has the rigidity, the strength and the bending strength.

A third disadvantage of light snow gliding boards concerns power transmission on the snow. A high power transmission from the feet to the shoes, Bindings and straps in the steel edges enable precise steering and Steering and rapid maneuvers. For this reason, snow sliding boards sought with high strength.

As a solution, document WO 97/06864 discloses a ski in which the binding carrier in a shell construction, it grips the core laterally, so that it such mechanically decoupled binding carrier twists and forces Resist in the longitudinal and transverse directions of the snow sliding board. In the top chord Viscoelastic damping layers are provided to prevent vibrations and dampen blows quickly. This mechanically decoupled binding carrier also allows high power transmission in the treads.

This solution with a mechanically decoupled binding carrier that the The core grips laterally, can only be used for relatively narrow skis. snowboards on the other hand are much wider than skis, typically at least twice as wide. The side laminates that absorb the thrust are too small for snowboards; they would have to be reinforced what to Leads to thickness and weight problems.

The document FR-2 667 536 discloses a snow sliding board in a layered construction with a core which contains a zone with a honeycomb structure which extends over its entire thickness and the rest of which is formed by a polymer mixture. This snow sliding board also has the disadvantages described above - in particular low absorption capacity of shear stresses, low shear and pressure resistance. The core is produced separately by placing the honeycomb structure in a mold and overmolding with the polymer mixture. After the core has been manufactured, the snow gliding board must be assembled from the core and other components. This multi-stage manufacturing process is complex and costly.
DE 295 16 548 on the side of the preamble of claim 1 report and DE 196 04 016 show two further snow sliding boards. These also have the disadvantages inherent in the prior art described above.
It is an object of the invention to solve these disadvantages in a simple construction. In particular, it should provide snow sliding boards with a low weight, high shear strength and high pressure resistance. A high control force transmission is also sought. It is also an object of the invention to provide a manufacturing method for snow sliding boards. The invention relates to snow sliding boards such as skis, big feet, snowboards, etc., but in particular to snowboards.

This object is achieved by the invention defined in the claims.

The idea according to the invention consists in the development of lightweight components for static and dynamic types of loads such as those for Snow sliding boards occur. There is a core matrix between the lower and upper chord from very light core materials as well as from reinforcement materials arranged with higher strength, preferably high-strength materials. This sandwich composite lightweight construction allows high dynamic Withstand bending and compressive loads. The reinforcement materials higher strength are in areas of very light core materials admitted. It is advantageous to form a core matrix, in which mainly take on very light core materials and with locally attached reinforcement materials of higher strength Bending, compressive and shear loads are stabilized.

The resulting very light snow sliding board is characterized by a high shear and pressure resistance, because the reinforcement materials of higher strength are embedded in recesses of the very light core materials in accordance with the main directions of stress, in order to increase the core shear modulus, the core shear strength, the core pressure resistance, the component rigidity and the component strength increase. A combination of very light core materials such as honeycomb materials such as phenolic resin-impregnated aramid paper (Nomex), polyetherimide (PEI) tubular honeycomb, or foamed plastics, with reinforcing materials of higher strength such as thermoplastic plastics, e.g. B. poyamides, polyimides or polystyrenes, fiber-reinforced plastics, for. B. glass fiber reinforced plastics (GRP) or carbon fiber reinforced plastics (CFRP), acrylonitrile butadiene styrene (ABS), or wood or metals. The following table gives typical strength values for some of the above materials. Accordingly, the reinforcement materials used have strikingly higher strengths than the light materials used; So it makes sense to call them higher strength materials. use as material Compressive strength (MPa) Shear strength (MPa) Shear modulus (MPa) Density (kg / m ³ ) light material Nomex honeycomb 3.9 2.0 63 64 reinforcing material Wood (average value in grain direction) 140 40 1200 650 reinforcing material GRP laminate in the grain direction 500 200 15000 1850

In the method according to the invention for producing a snow sliding board areas of reinforcement materials by gluing with areas made of light materials. The individual components of the core are preferably in one with all other parts of the snow sliding board Formed and glued to the finished product in a single step. The Functional kernel is therefore not preceded by a separate process manufactured, but the components only have to be pre-assembled accordingly become. The individual areas have proven to be particularly suitable with each other and the areas with ends and with cover straps by means of to glue the known prepreg process.

Figur 1

zeigt schematisch Kräfte und Drücke, welchen ein (in Seitenansicht dargestelltes) Schneegleitbrett bei Belastung ausgesetzt ist.

Figuren 2-5

zeigen Längsschnitte durch beispielhafte Ausführungsformen des erfindungsgemässen Schneegleitbrettes.

Figur 6

zeigt einen Querschnitt durch eine weitere beispielhaften Ausführungsform der Erfindung.

Figur 7

zeigt eine teilweise offengelegte Ansicht eines Wabenmaterials zwischen zwei Deckgurten.

The invention is explained in detail with reference to the following figures.

Figure 1

shows schematically forces and pressures to which a snow sliding board (shown in side view) is exposed under load.

Figures 2-5

show longitudinal sections through exemplary embodiments of the snow sliding board according to the invention.

Figure 6

shows a cross section through a further exemplary embodiment of the invention.

Figure 7

shows a partially exposed view of a honeycomb material between two cover belts.

For a more general representation of the problem, a snow gliding board, for example a snowboard, is shown in side view under a typical load in FIG . A snowboarder (not shown) exerts two forces F1, F2 on the snowboard with his two feet. A bending of the snowboard leads to a pressure s1 on an upper side 2 and a pull s2 on a lower side 3 of the snowboard. A thrust s3 can also act.

FIGS. 2 to 5 show longitudinal sections parallel to the base surface 3 of the snow sliding board through parts of exemplary embodiments of the present invention. All of these embodiments have in common that they relate to a snow sliding board in the embodiment of a snowboard. Of course, the idea according to the invention, even if not explicitly shown, can also be applied to other snow sliding boards such as skis or big feet, etc. Figures 2 to 7 show longitudinal sections through the snow sliding board and through its core 1 , which consists of several areas of different materials.

FIGS. 2 to 5 show a core matrix, comprising areas 11, 13 made of light material and a large number of more or less symmetrically arranged, more or less large and more or less mosaic-like inner areas 12.1, 12.2 ... and delimiting outer webs 14, 15 made of reinforcing material. The areas can be more or less large, they can, but do not have to be connected to one another and they can be of any shape. With knowledge of the present invention, the person skilled in the art has almost unlimited design options for a core matrix. It is generally the case that areas of reinforcement material are selectively attached in terms of size and orientation so that the orientation of the reinforcement materials corresponds to the loading directions of the snow sliding board.

The dimensioning, ie the relative size of the individual areas 11, 12.1, 12.2, ..., 13, 14, 15 and the front ends 45 and rear ends 54 is freely adjustable. Figures 2, 4 and 5 show relatively narrow outer webs 14, 15 and relatively short front ends 45 and rear ends 54 , while the intermediate regions 11, 13 occupy relatively large areas or volumes. In Figures 4 and 5 , the inner area is practically reduced to binding bases 12.1, 12.2 . These variations in dimensioning take into account user wishes and lead to snow sliding boards that are differently stiff, more or less light and differently spritzig and maneuverable. Furthermore, these variations in dimensioning take into account the light and strengthening materials used. Particularly high-strength materials require smaller areas or volumes than normal high-strength materials. Depending on the ratio of the light to the high-strength materials, the weight reduction is approximately 20-40% compared to snowboards with a standard construction with conventional core materials such as wood with an average density of approx. 600 kg / m ³ .

The high-strength reinforcing materials do not necessarily have to be laid flat or two-dimensionally in recesses of the very light core materials, as described previously, but they can also be looped three-dimensionally as tabs through slotted core materials. An exemplary embodiment of this is shown in FIG. 9 . The material of the straps 20, 30 can be high-strength reinforcing material. Tabs 20.1, 20.2 made of high-strength belt material allow a direct connection from the tension belt 30 to the compression belt 20.

The reinforcing materials serve to absorb forces acting between the tension belt 30 and the compression belt 20 . In particular, areas 12.1, 12.2, ..., 14, 15 made of reinforcing materials enable the snow sliding board to be subjected to high bending loads. The areas 12.1, 12.2, ..., 14, 15 made of reinforcing materials also serve as local reinforcements for application-specific purposes, for example to form binding bases 12.1, 12.2 and to support the steel edges 40 . Other possible uses, not listed here, of locally reinforcing materials are of course possible. The areas made of reinforcing materials stabilize the areas made of light materials when the snow sliding board is subjected to dynamic bending stress. As is known, the shear and compressive strength of the light materials, such as honeycomb materials, drastically decrease under bending stress, for example because the cell walls of a honeycomb are no longer perpendicular to the load plane during bending and shear displacement. This low shear characteristic of the load-bearing lightweight materials is avoided by local integration of the reinforcement materials, which are resistant to shear even under bending stress; the honeycombs are thus stabilized even under high bending loads. This core matrix, which is reinforced and stabilized in a mosaic-like manner according to the loading directions of the snow sliding board, only enables the successful use of light materials with low shear characteristics.

According to FIGS. 2 to 5 , areas 12.1, 12.2,..., 14, 15 made of reinforcing materials are connected to one another with high strength via front and rear ends 45, 54 made of reinforcing materials. This makes it possible to reinforce the highly stressed edge zones of the snow sliding board in a highly rigid manner. Areas 12.1, 12.2, ..., 14, 15, 45, 54 made of high-strength reinforcing materials can be connected together in a closed manner. However, this is not a requirement. In general, this sandwich composite structure has a high shear modulus in the longitudinal direction, it is very pressure and bending resistant. In particular, this snow sliding board has a high torsional rigidity and it has a high damping behavior. Its component rigidity and component strength are increased. Glass fiber reinforced plastics (GRP), carbon fiber reinforced plastics (CFRP), acrylonitrile butadiene styrene (ABS), wood, etc. are advantageously used as reinforcing materials. This list is not exhaustive. With knowledge of the present invention, the person skilled in the art can also use other reinforcing materials such as metals, for example steel and / or aluminum.

The light core materials serve to keep the weight of the snow sliding board low. Materials with cavities such as honeycomb materials with typical cell diameters of 3 to 10 mm or closed cells with a density of not more than 400 kg / m ³ are advantageously used as light materials. With a snow gliding board in the form of a snowboard with typical dimensions such as 1500 mm in length, 290 mm in maximum width and 10 mm in maximum thickness, this results in dead weights of around 2.3 kg, which represents a weight reduction of approximately 20-40% compared to snowboards with standard construction , This variation in weight reduction is a result of the proportion of (slightly heavy) high-strength reinforcement materials on the snowboard.

FIG. 7 shows a partially disclosed view of a honeycomb-shaped light core material 6 between a tension belt 30 and a compression belt 20 . The honeycomb material 6 consists of a plurality of preferably prismatic cells 6.1, 6.2, ... with, for example, hexagonal or round cross-section, the axes a of which are preferably perpendicular to the longitudinal axis A of the snow sliding board. Various honeycomb materials 6 made of metallic materials such as aluminum, or of non-metallic materials such as plastics such as polypropylene (PP), polycarbonate (PC), polyetherimide (PEI) or phenolic resin-impregnated aramid paper (Nomex) etc. are commercially available. Honeycomb materials 6 are preferred not only because of their low density, but also because of their extraordinary weight-specific compressive strength. In the direction of the cell axes a, the honeycomb materials are hardly compressible, that is to say highly pressure-resistant, but have a relatively low shear modulus or a relatively low shear strength compared to conventional core materials. This also applies to alternative light materials, such as foamed, non-reinforced plastics.

The exact processing of honeycomb materials 6 , but also of other light materials such as plastics, synthetic fibers, prepregs, etc., is carried out, for example, by ultrasonic cutting. Other processing methods of honeycomb materials and light materials as well as other ultrasonic cutting methods are of course applicable. A CNC-controlled ultrasonic cutting with CAD interface is advantageous, which allows a quick and economical cutting and which allows rapid changes for cutting variations. The precision of the cut in series production is, for example, with a contour accuracy of approximately +/- 0.2 mm. It is also advantageous that there is no heat and media exposure during cutting, which is disadvantageous in other cutting methods such as laser and water jet cutting, since cut edges can be deformed, damaged and contaminated.

The lightweight and reinforcing materials mentioned in the present invention cannot be fully listed, there are too many of them. Those skilled in the art can, with knowledge of the present invention, further materials and add combinations. For example, honeycomb materials are also usable with higher density or they are also honeycomb materials usable with smaller or larger cell diameters.

Cavities of the light materials, such as honeycomb materials 6 , can also be filled locally with strengthening materials so as to act locally as a reinforcing material in the sense of the invention. Examples of strengthening materials are foams and pastes made of plastic, such as polyurethane (PUR) or GRP, ABS or metal, wood, etc. Finally, cavities of the light materials, such as honeycomb materials 6 , can be locally filled with viscoelastic materials so as to be locally viscoelastic and to dampen vibrations and impacts quickly.

The permanent stable connection of the individual areas 11, 12.1, 12.2, ..., 13, 14, 15 with each other, as well as with front and rear ends 45, 54 , and with cover straps 20, 30 is advantageously by gluing, for example by means of the known prepreg -Procedure carried out. Prepregs are reinforcing materials that are soaked with pre-reacted thermosets or thermoplastics before being joined. For example, thermosetting thermosetting epoxy resins are used as the prepreg matrix. Flat sandwich components can be manufactured relatively economically, for example in the pressing process. Sandwich components consist of relatively thin outer layers and a relatively thick but light core. The cover layers are mostly high-strength belt materials that are glued to the core materials with high compressive strength and low weight. The tough, elastic prepreg matrix and the use of a formable bedding matrix open up a wide range of component design options.

For the production of the very light, shear and pressure resistant according to the invention Snow gliding boards for dynamic bending loads are preferred known prepreg method used. The prepreg process stands out due to low process costs and is economical because all materials and parts fully automatically with epoxy resin contained in the prepreg can be glued without using additional adhesives. For example is used as a tough elastic prepreg matrix epoxy resin in the B-state. When heat is applied, the resin viscosity is reduced and the resin can Wet components with resin flow. In the variant of the used here Prepreg processes are massive, milled to the contour of the workpiece Tools are used that are spatially constructed according to the requirements are. Walls that are at an angle to the press plane can be frictionally engaged be pressurized. The polyaddition of Resin and hardener is strong on the temperature level, the pressing pressure and depending on the exposure time. The use of prepreg ensures uniform resin content in the sandwich composite and high reproducibility the connection. Flexibility is also important. So can on a press simultaneously different molded parts with accordingly milled tools.

In the prepreg process used here occurs immediately after the Curing of practically finished parts; it is characterized by a low manufacturing effort in part preparation and post-processing such as deburring, Smoothing, painting, etc. In particular, graphically designed Surfaces can be glued without additional effort. The one used here Prepreg process is not different on joining Light materials and reinforcement materials to a flat (two-dimensional) Sandwich components limited, but also allows one economical sandwich lightweight construction of three-dimensional parts. For example a combination with the pressure bag method is possible, so that a Pressure bag is either integrated in the molded part or locally in the tool and an even pressure transfer in three dimensions (on all levels) he follows.

The person skilled in the art can of course also know the present invention use other known connection techniques and other connection means. Examples include wet lamination, reaction injection molding (RIM) technology, Resin Transfer Molding (RTM) process or a Gluing with adhesive films, adhesive films, adhesive-coated laminates made of plastics or fiber-reinforced plastics such as GRP, CFRP, ABS, PFK made of metals such as aluminum etc. listed. When combined with an injection process, an expanded system is injected into the molded part, the activation of the foaming system subsequently by heat, can take place during the pressing process. By means of such connection techniques light materials and reinforcement materials as well as cover straps connect to break-resistant flexible snow sliding boards.

Claims (7)

1. Snowboard comprising a core (1) between a base sheet and a top sheet (20, 30), the core (1) having at least one region of light materials (11, 13) and at least one region of reinforcing materials (12.1, 14, 15) and fastening means (12.1) for the binding, characterized in that in the region of the front and rear ends of the snowboard, regions (12.21, 12.22, 12.31, 12.32, 12.41, 12.42, 12.51, 12.52, 12.5, 12.6, 12.71, 12.72, 12.81, 12.82, 12.9) locally limited to these regions and comprising reinforcing materials are arranged and are surrounded by light material.
2. Snowboard according to Claim 1, characterized in that regions (12.21, 12.22, 12.31, 12.32, 12.41, 12.42, 12.51, 12.52, 12.5, 12.6, 12.71, 12.72, 12.81, 12.82, 12.9) consist of reinforcing materials and that at least one intermediate region (11, 13) consists of light materials, the light materials performing load-bearing functions and the reinforcing materials stabilizing the light materials to shear stress and compressive stress.
3. Snowboard according to Claim 1 or 2, characterized in that regions (12.21, 12.22, 12.31, 12.32, 12.41, 12.42, 12,51, 12.52, 12.5, 12.6, 12.71, 12.72, 12.81, 12.82, 12.9) comprising reinforcing materials are mounted specifically in terms of size and alignment so that the orientation of the reinforcing materials corresponds to the main stress directions of the snowboard.
4. Snowboard according to any of Claims 1 to 3, characterized in that the light materials have a density of not more than 400 kg/m³ and that the light materials are honeycomb materials (6) whose cells (6.1, 6.2) are aligned perpendicular to the longitudinal axis (A) of the snowboard.
5. Snowboard according to any of Claims 1 to 4, characterized in that the reinforcing materials are high-strength glass fibre-reinforced plastics and/or carbon fibre-reinforced plastics and/or metals and/or wood.
6. Snowboard according to any of Claims 1 to 5, characterized in that tabs (20.1, 20.2) of sheet material are looped through slotted light materials (13) and base sheet (30) and top sheet (20) are directly connected.
7. Snowboard according to any of Claims 1 to 6, characterized in that in accordance with the ratio of light materials to reinforcing materials, the snowboard is 20% to 40% lighter than a comparable standard construction.

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