DE102007048562A1 - Water ski or surfboard has hollow core surrounded by fiber composite mantel consisting of epoxy-resin impregnated carbon fiber fabric - Google Patents

Abstract

The water ski or surfboard (10) has a hollow core (40) surrounded by a fiber composite mantel. This consists of an epoxy-resin impregnated carbon fiber fabric (31) : An independent claim is included for a method for making the water ski or surfboard comprising producing the desired flexibility and characteristics through the design, structure and materials chosen (sic).

Description

The The present invention relates to a water sports device, in particular a water ski or a surfboard, as well as the construction of a water sports equipment having the features of the preamble of the independent claim 1. Furthermore, the invention relates to a process for the preparation a water sports equipment with the characteristics of the generic term of the independent method claim.

State of the art

The first known board-shaped surfboards, water boards, Water skiing etc., which served the water sports, were stiff and heavy and often had hard outer surfaces on. Later, more and more synthetic materials became available used to make lightweight boards. For example, were Boards made of a plastic core, impregnated with resin Material is wrapped around to prevent absorption of water. The hard outer skin of the conventional, heavy Boards offered good resistance to bending forces, whereas the light boards are repeated due to water sports occurring bending and torsional forces sometimes fast are broken.

The DE 3129007 C2 describes a conventional fiberglass-reinforced synthetic water ski and a method of making the same. The cavity between the mating shells can be filled with plastic foam, for example. DE 8328489 U1 and DE 3335974 A1 show pairwise to be used so-called. Dolphin water ski, which have on its underside movably mounted large fins. The floats are fully foamed with GFK.

The FR 2638374 A1 shows an arrangement by which a board of several layers of plywood obtains advantageous qualities in terms of strength and flexibility. The board consists of 5 layers of plywood ( 1 ) and ( 2 ), which are each arranged so that the wood fibers of adjacent layers are perpendicular to each other and a layer of carbon fiber or Kevlar ( 3 ). The arrangement is preferably intended for use in skateboards (with or without sails) and snowboards, but can also be used for swimming boards.

The EP 783429 B1 discloses an improved water sports board having an elongated core made of a low density filler material (e.g., extruded polystyrene foam or the like) and enclosed by a highly stable composite skin. Between the composite outer skin and the core, an elastic, impermeable layer is arranged.

The DE 29620466 U1 describes a Wasserwanderlaufski, which consists of two non-rigidly coupled together floats. As the floating body, a hollow body made of plastic or other material is used, which may be filled. JP 11079075 AA shows a water ski coming out of a main body 2 , Bindings 3 and a Finn 4 consists. The main body 2 contains a longitudinally oriented core material 5 , consisting of a hollow body made of aluminum. The main body 2 is through a surface layer 7 enclosed, which is reinforced with carbon fiber.

From the JP 10165559 AA is a very lightweight sports board known that meets great mechanical requirements. The core material again consists of foamed plastic between a lower layer 2 and an upper layer 3 , where the layers 2 and 3 made of a textile material that was previously soaked in epoxy resin. DE 19853265 C1 shows a multilayer sliding board with a weight-saving core stretched in the direction of thickness thermoplastic. Between the running or sliding surface and the lightweight core 4 are layers of epoxy fiberglass 5 and aluminum 6 arranged.

The FR 2787088 A1 describes a surfboard that is sandwiched. It consists of a calibrated core ( 4 ) of soft foam, for example. Polystyrene and a skin ( 3 ), for example of glass fiber or carbon fiber. The skin is additionally impregnated with an epoxy resin. Subsequently, this polymerization and flattened under vacuum. In order to control the flexibility, carbon fiber reinforcements may be used which are oriented in one direction. The board is further protected with a layer of protective paint against ingress of water.

The DE 10036185 A1 describes a method for producing a composite material from a particle foam of a thermoplastic material and at least one associated with this layer.

The DE 10 2005 037 386 A1 shows a pneumatic body having a compressed air acted upon lust and gas-tight flexible cavity-forming envelope. The shell is made of plastic sheets or foils. US 20060178061 A1 describes an arrangement to be used on the water consisting of a foamed core within which a hollow structure is arranged. On the surface are structured fibers, for example. Fiberglass fibers, carbon fibers or thermoplastic materials.

Another problem with lightweight boards is a hard porous skin in that the boards are essentially very stiff. As a result, these boards are generally easily fragile, which entails an enormous risk of injury.

in the Water skiing is better for water sports Features generally "soft" water ski with one good flex value preferred. To conventional waterskis this To lend desired properties, these become common By drilling "softer" made by the flexibility of the board. However, these holes contain a big danger in itself. Because the board at the drilling sites is specifically weakened, there is an increased risk of breakage. The boards may break during use, u. z. preferably between the bonds or at the places where the bonds begin.

description

Out For this reason, the object of the present invention is to to provide a water sports device that is lightweight, one has controlled flexibility and no risk of breakage consists. Furthermore, it should be possible to use boards with certain Flexibility characteristics according to customer-specific wishes to be able to design and exactly reproduce

This The aim of the invention is with the subject of the independent Achieved. Features of advantageous developments of the invention result from the dependent claims.

The The invention relates to a water sports device, in particular a water ski or a surfboard. The invention is mainly described in terms of a water ski, but is for other board-shaped water sports equipment and sports equipment as well applicable.

One Water ski according to the invention is at least in his Sheath area essentially made with carbon fiber fabric. It is a fabric of industrially manufactured Fibers made from carbonaceous raw materials These are arranged by pyrolysis in graphite Carbon are converted. This can be isotropic and anisotropic fibers are produced. Technically significant are the Anisotropic fibers that contribute high strength and stiffness have simultaneously low elongation at break. Carbon fibers are electrically very good and thermally low conductive. she have a negative thermal expansion coefficient in the longitudinal direction. When heated, they are therefore shorter and thicker. Another advantage of carbon fiber fabric is that It is particularly light at high strength. In addition, can be define the elastic properties very precisely, by the fabric layers in terms of fiber orientation, their Density, its thickness and number are varied. These properties can be used in industrial, d. H. with automated production reproduce very precisely with precisely manufactured tissue blanks, so that mass production with very little dispersion of mechanical Properties is possible.

Of the Waterskiing generally has the conventionally known Shape up. Beispielseelse is the water skiing at the front end after bent up and has a soft rubber boot or equivalent Bindings in which the feet find support. The lead of the water ski is through a small fin ensured on the underside of the board in the rear area.

The Invention is applicable for different versions, eg. in those where the athlete on two parallel water skis stands. Preferably, the invention relates to a so-called. Monoski, where the athlete with both feet on one Board stands. The monoski consists of only one skis with fin, up behind the binding a simple loop for the second Foot is attached. Optionally, a second bond may be similar be provided the front binding. The bottom of the monoski is generally curved in the middle of the length inside.

Of the Water ski according to the invention has in contrast preferably none to the conventionally known mono-skis Foam core on, but is hollow inside. Of course Optionally, a foam core o. The like. Be present, the of a jacket area made of impregnated with epoxy resin carbon fiber fabric is enclosed. The ski can be very stable and at the same time very easy to fail. The ski can be tailored to the needs be adjusted by the customer, because the desired flex value can be adjusted individually.

The inner cavity can optionally be divided by several longitudinal webs into a plurality of hollow chambers. The bars are made of resin-reinforced carbon fiber fabric. But there are also variants without such longitudinal webs possible. Optionally, instead of closed bar profiles and open profiles with openings, individual column sections o. The like. Serve as longitudinal webs. The longitudinal webs can also be designed in each case as raised profile strips of defined height on the upper and / or lower inner side of the jacket region. These longitudinal webs thus form no connection between the top and bottom of the board. Numerous other variants are conceivable and possible. There are two, three or more such longitudinal webs conceivable. In addition, transverse webs may be provided, optionally also in closed or open embodiment. With closed longitudinal webs and closed transverse webs a plurality of each closed chambers are formed, which can reliably prevent sinking in the water in case of breakage of the board.

The mentioned bridges - whether with or without connection between the top and bottom of the board - but offer Numerous significant advantages of the invention Ski. The webs can, for example, by regularly replaced or supplemented columns, connect the top and bottom. It is also possible only on the top or only on the bottom or on both inner sides Bridges lower height to install, each not with the other side are connected and thus no closed chambers form. Such webs defined height, material thickness and fiber structure serve to increase the flexural rigidity, as this, for example, beads or stiffening webs in steel or in metal construction would allow. Not least However, the webs also serve to elasticity and the deformation behavior of the board over its length and width to define very accurately and with repeated production to reproduce as exactly as possible.

Of the Sheath area of the board may optionally be by layers of aramid fibers be strengthened. These very tear-resistant aramid fibers reliably prevent all breakthroughs of the board, For example, in its failure in case of overload. The aramid fibers can optionally in the epoxy resin and / or in the region of the fabric layers be embedded in the carbon fiber fabric.

The Production of the water sports equipment, in particular water skis can according to known prior art, for example. In take a suitable mold, the length and Form of the ski pretends. This mold can be made of different ones Materials consist, such as. From CFRP plastic material, which it is very wear-resistant. With such a mold A large number of skis can be made before that Forming tool needs to be renewed. The impregnated with epoxy resin Carbon fiber fabric is inserted into the mold. Between the Upper layer of carbon fiber fabric, which is the top of the board forms and the lower layer carbon fiber fabric can plastic hoses be inserted. Between these plastic tubes comes resin impregnated carbon fiber fabric for crossbars or longitudinal webs, with the upper and the lower fabric layer is connected and the board additional stability gives. Then comes the prepared arrangement in an oven. There the temperature and the pressure are controlled increased within the plastic tubing, so that These inflate and the soaked carbon fiber fabric attaches to the mold and thus exactly the desired shape accepts. Subsequently, the mold with the so produced ski removed from the oven and the ski cools in the form. Since preferably both the mold and the Ski made of very hard CFK material, finds no thermal expansion instead, so that a board can be reproduced exactly. This poses one of the big advantages over conventional ones Water skis. These are often cured outdoors, which can lead to a delay of the board. The preference can different and unpredictable on every board, so that no identical water skis can be made.

The Water sports board according to the invention is above all also reproducible because each item before exactly (with Cutter) in identical form (identical orientation, layers, etc.) is produced and placed in the mold only in a single position fits (comparable to a puzzle). The blanks, the order and position of the blanks when inserting into the mold and the Structure of the individual layers and layers is always complete Documentable and therefore exactly reproducible. The shape prevents then any delay, what the exact reproducibility can guarantee.

The Skiing made with carbon fiber can be in their flex value be adapted exactly to the needs of the water sportsman. For example, the webs described above in the interior of thicker or can be made thinner, as well the number of webs used to be varied accordingly. Farther the choice of carbon fiber fabric used plays a crucial Role, for example, by changing the fiber direction the location and strength of the flex value are specifically influenced can be. Another variable factor is the density of the For example, in certain areas on the top or bottom or in the side walls more or fewer layers of carbon fiber fabric are used to make the appropriate to obtain desired flexibility. It can more or less layers are used. In addition, a variation the orientation and / or the material (eg also mixed with aramid) to get voted. Thus, the flex value is on demand and customer request variable and can also be reproduced exactly.

This is particularly advantageous because many water sports professionals train at several locations and do not always want to take their sports equipment, but want to deposit devices with as exactly the same properties at these different training locations. In conventional boards, this exact reproducibility is due to the not described above during curing, so that each board has its own characteristics. Although the differences can be very small, but feels a professional even these small differences as disadvantageous.

According to one preferred embodiment of the invention, the waterski between the carbon fiber fabric layers a layer of aramid fibers or Aramid fabric on. Aramid fibers are golden yellow organic synthetic fibers. The fibers were marketed under the brand name Kevlar. The fibers are characterized by very high strength, high impact strength, high elongation at break, good vibration damping and durability against acids and alkalis. They are above In addition, very heat and fire resistant. Because of their tear or tensile strength and their low weight are aramid fibers commonly used in sports equipment, so for example for the suspension lines for paragliders, for sails of sailboats and surfboards or as strings for tennis rackets. In the context of the present invention, the layer is aramid fiber as extra security, to break the board To prevent and thus injuries when using the water sports equipment (i. d. R. only in case of overload or misuse, because normally it does not break).

To Curing the board will be the extra Components installed. These include, on the one hand, the adjustable Fin to control and fixtures for attaching the bindings. The Fin consists of a dimensionally stable, corrosion-resistant Material, for example. Of light metal or carbon and can be different Shapes have. In general, the fin has a rounded Shape up. The fins are adjustable (in the direction of travel and in the Height). The fin gets up in the back of the water attached to the bottom, for example, the fin is screwed or glued on. As a rule, a glued fin box is off Milled aluminum or made of CFRP plastic available to the the ski is glued. The fin itself is usually clamped, eg. by means of two or three screws. The fin can be misaligned or be removed from the fin box when the clamp is released is.

Farther are in the middle area fastening devices for the bindings provided. Preferably, such binding plates are not attached directly to the ski but over intermediate means, for example about Velcro, bolts or the like, for example are attached, attached. For example, a kind of Velcro (for example, dual-lock from 3M), which glued to the board and then the bindings via an appropriate Adhesive surface ("Gegenklett") are attached. Another alternative is the use of so-called "studs" or "click bonds", which also stuck on the board and with which a plate can be screwed on the the bindings are on or a thin glued on Steel plate with threaded bolt.

One Another advantage of this water sports equipment is that due to the material used, the life virtually infinite is while traditional water sports equipment generally be replaced after a certain period of use have to. Traditional water skis are more limited Time softens (see Alpinski), because the foam core crumbles. The foam core hardens - even inside, d. H. in the absence of light - with time off and tends to break or disintegrate, increasing the structural strength of the board is impaired. Under high load - eg. in professional use - that is why the boards age very much fast and are often already "softened" after less than two years and no longer usable under competitive conditions, as the properties suffer and worsen. Another disadvantage of the foam core is due to the fact that with all cracks and damages Water enters, whereby the foam core is fully sucked, considerably increases in weight and rotted after a long time.

by virtue of of the stable high quality material used the walls of the water sports equipment relatively thin be designed. Furthermore, the invention contains Water sports equipment preferably no foam core, as in used many conventional boards or water skiing becomes. As a result, a huge reduction in weight is possible.

The Invention is for a variety of variations and modifications conceivable that of the inventive concept Use and therefore also fall within the scope of protection. In particular, the invention is for the manufacture of other water sports equipment (Surfboards o. Ä.) Suitable and should include.

In the case of surfboards, for example, there is the additional requirement that they should not sink in the event of a break, crack in the wall o. Ä., As the board also serves the athlete as a survival board to which he can hold on and thus save. Boards of carbon fiber fabric impregnated with the resin of the invention and reinforced with aramid should have no breaks, cracks, etc. As an additional safeguard, however, further transverse webs can serve in the interior of the board, which allow a further subdivision into smaller hollow chambers. In the case of a crack, the area would be where water penetrates can thus be limited locally, so that not the entire board can run inside and thus go down.

figure description

Further Features, objects and advantages of the present invention will be apparent The following detailed description of a preferred embodiment of the invention, as a non-limiting example serves and refers to the accompanying drawings. Identical components basically have the same reference numerals on and are sometimes not explained several times.

1a / b generally show the shape of water ski with fin and bindings (known prior art);

2a / b / c show a cross section through a water ski constructed according to the invention;

3a / b show two embodiments of a partially cut-open surfboard 50 of inventive construction

A possible embodiment of a water ski 10 corresponds in the outer structure known from the prior art water ski and is based on 1a / b illustrated.

The water ski 10 has a board shape. The front end 20 is tapered, rounded and slightly bent upwards. In the middle area 24 The water ski has devices for attaching bindings 26 on. In the back area is a fin 22 appropriate. The back area 22 can have different shape. For example, the rear area 22 also taper to the rear and complete rounded.

The Finn 22 For example, is made of a stainless steel, for example. Of a light metal or a saltwater-resistant stainless steel material. The fin can also be made of another corrosion-resistant, dimensionally stable material, for example. From a CFRP material. The fin may have the shape indicated in the drawings or - for example, depending on the customer - be designed differently.

As bonds 26 can - as in 1b shown - the conventionally known bindings in ski boot-like form or simplified bindings in loop form o. Ä. Are used.

The 2a / b / c show a cross section of a water ski according to the invention 10 , And indeed, the water ski at the interface A (see. 1b ) cut open. The water ski 10 consists of a resin impregnated carbon fiber fabric reinforced in sections with aramid fibers 30 , The structure of the board in the area of the top and bottom is based on 2c shown. There you can see that between several layers of carbon fiber fabric 31 at least one layer of aramid fiber fabric 32 is integrated. The reinforcement by means of the layer of aramid fabric 32 serves the additional resistance to breakage, as a breakthrough of the board can be additionally prevented by the integration of the fabric layer of break and tear-resistant material.

The cross-sectional view of 2 B shows a possible distribution of longitudinally oriented aramid fiber layers 32 in the area of the top and bottom of the board. At the top, the aramid fibers are enough 32 not quite to the longitudinal edges, while at the bottom of the board the aramid fibers 32 are laid in the rounded edge sections.

The water ski according to the invention 10 is in the longitudinal direction several times in hollow chambers 40 divided. The demarcation between the different chambers 40 done with bars 36 made of resin-impregnated carbon fiber fabric 31 consist. The bridges 36 Both with the upper layer and with the lower layer aramid fibers reinforced carbon fiber fabric 30 be connected. In the chambers 40 are the remains of the plastic tubes used in the manufacture of the board (not shown), which do not interfere with the properties of the board and also lead to no significant additional weight. For this reason, the tubes do not become out of the chambers after manufacture 40 away.

The 3a and 3b show a surfboard 50 in that of resin impregnated aramid fiber reinforced carbon fiber fabric 30 was produced. According to the in 2a / b / c illustrated construction of water skiing 10 is the in 3a illustrated embodiment by means of longitudinal webs 36 into several hollow chambers 40 divided. In the 3b illustrated embodiment is also by further transverse webs 38 in several small cavities 41 divided up. The longitudinal webs 36 and the crossbars 38 each consist of resin-impregnated carbon fiber fabric 31 , This is an additional safety factor. Should the board 50 have a crack, the water would be limited only locally in the corresponding chamber 41 penetration. This will prevent the board 50 fully sucks and goes down.

In a relatively simple way, a variant with a continuous crossbar can be realized. In each case hoses are inserted from the front and from the rear, through the cross bar from each other are separated.

The The invention is not limited to the above embodiments limited. Rather, a variety of variants and Modifications conceivable that of the invention Use your thoughts and therefore also in the protection area fall.

10

Water-skiing

20

curved top

22

fin

24

Area, in which bonds are arranged

26

bonds

30

resin-impregnated Aramid reinforced carbon fiber fabric

31

resin-impregnated Carbon fiber fabrics

32

Aramid layer

36

longitudinal webs (resin impregnated carbon fiber fabric)

38

crossbars (resin impregnated carbon fiber fabric)

40

chamber

41

chamber

50

surfboard

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 3129007 C2 [0003]
• - DE 8328489 U1 [0003]
• - DE 3335974 A1 [0003]
• FR 2638374 A1 [0004]
• - EP 783429 B1 [0005]
• - DE 29620466 U1 [0006]
• - JP 11079075 AA [0006]
• - JP 10165559 AA [0007]
• - DE 19853265 C1 [0007]
• FR 2787088 A1 [0008]
• - DE 10036185 A1 [0009]
• - DE 102005037386 A1 [0010]
• US 20060178061 A1 [0010]

Claims (14)

Water sports board ( 10 . 50 ), in particular water ski or surfboard, with a core region defining the volume of the board and with a closed jacket surrounding the core region, which is essentially made of a fiber composite material, characterized in that at least the jacket region consists of a carbon fiber fabric impregnated with epoxy resin ( 31 ) and that the core area enclosed thereby is substantially hollow. Water sports board according to claim 1, characterized in that the carbon fiber fabric ( 31 ) Has reinforcements of aramid fibers. Watersporting board according to claim 1 or 2, characterized in that the mantle area is defined by one or more aramid fiber layers ( 32 ) is reinforced. Watersport board according to claim 2 or 3, characterized in that the aramid fibers in the carbon fiber fabric embedded in the cladding region. Water sports board according to one of the preceding claims, characterized in that the hollow core area by at least one longitudinal web ( 36 ) into several hollow chambers ( 41 ) is divided. Water sports board according to one of the preceding claims, characterized in that the hollow core area by at least one transverse web ( 38 ) into several hollow chambers ( 41 ) is divided. Process for the preparation of a water sports board according to one of claims 1 to 6, characterized that the elastic properties and characteristic values are determined by arrangement, Structure and material thickness of the jacket area individually are definable. Process according to claim 7, characterized characterized in that the flexibility of the water sports board through the material structure and / or density of the fabric layers used is defined variably on carbon fiber fabric. A method according to claim 7 or 8, characterized in that the flexibility of the water sports board by the number of fabric layers used on carbon fiber fabric is defined variably. Method according to one of the claims 7 to 9, characterized in that at least three different Strengths or flexibility values through variations the structure, number or thickness of the fabric layers adjustable are. Method according to one of claims 7 to 10, characterized in that the flexibility of the water sports board by the number and / or thickness and / or structure structure and / or the use of different materials of the webs used ( 36 . 38 ) is defined variably. Method according to one of the claims 7 to 11, characterized in that the carbon fiber fabric through embedded and / or aramid fibers applied to the carbon fiber layers is reinforced. Use of a water sports device according to a of claims 1 to 6 as water skiing. Use of a water sports device according to a of claims 1 to 6 as a surfboard.