WO2017212041A1

WO2017212041A1 - Surfboard

Info

Publication number: WO2017212041A1
Application number: PCT/EP2017/064166
Authority: WO
Inventors: Stefan KLUG
Original assignee: Waterrebels Ug (Haftungsbeschränkt)
Priority date: 2016-06-10
Filing date: 2017-06-09
Publication date: 2017-12-14
Also published as: DE102016110761A1

Abstract

The invention relates to a surfboard (10) which comprises an underside (12), a top side (14), a rear-side surface (22) and a trailing edge (20) lying substantially vertically relative to a longitudinal extension direction of the surfboard (10). The trailing edge (20) is formed by an intersecting edge between the underside (12) and the rear-side surface (22). The top side (14) of the surfboard (10) extends, in a rear portion of the surfboard (10), at least partially beyond said trailing edge (20).

Description

surfboard

The invention relates to a surfboard with a spoiler edge.

The speed achievable with a surfboard is highly dependent on the construction of the underside of the surfboard, which is in contact with the water and thus accounts for most of the water resistance of the surfboard. Typically, surfboards are at rest and slow ride displacer, that is, they displace exactly the volume of water whose weight corresponds to the weight of the surfboard and the driver. With increasing speed, the surfboards become gliders, meaning they rise at least partially out of the water and slide on the water surface. An advantage for this is a flat hull with a large sliding surface.

When gliding due to the lower water resistance greater speeds can be achieved. However, here too the hull shape is decisive for the sliding friction on the water surface. There are different approaches to reduce water resistance at higher speeds.

EP 0 059 345 A1 discloses a high-speed surfboard which, due to its special underside construction, achieves low water resistance at both low and high speeds. This is made possible by a concave profiling in the longitudinal direction, a negative concave curvature in the transverse axis and laterally arranged buoyancy bodies.

Conventional surfboards are due to their hull construction unable to achieve at low speeds in a simple and comfortable way, a low sliding friction of the water and thus a low water resistance, since the water flowing along the trunk, especially in the back of the surfboard creates turbulence.

The invention is therefore an object of the invention to provide a robust surfboard available, which can achieve high speeds in a simple and comfortable way.

The object is achieved by a surfboard according to claim 1. Advantageous embodiments are specified in the subclaims 2 to 15.

A first aspect of the invention relates to a surfboard, which comprises a lower side, an upper side, a rear side surface, as well as a spoiler edge lying substantially perpendicular to a longitudinal extension direction of the surfboard. The tear-off edge is formed by a cutting edge between the bottom and the rear surface and the top of the surfboard extends in a rear part of the surfboard at least in sections beyond the spoiler edge. The underside, when used as intended, faces the water and has a sliding surface at its rear for sliding surfboard at higher speeds. Opposite, the upper side is arranged, which is typically designed to accommodate a lying, sitting and / or standing person and when used as intended faces away from the water and points substantially upwards.

The front part of the surfboard is the front part when used as intended in the direction of travel. This can be curved upwards and / or bent to avoid immersion of the front part into the water. When gliding, at higher speeds, the front of the surfboard can rise out of the water and stick out.

The back of the surfboard is the rear part in the direction of travel. At standstill and lower speeds, substantially the entire underside is in contact with the water and partially submerged.

The rear surface is aligned against the direction of travel when used as intended, thus facing backwards. The back surface and thus the trailing edge are straight in the plan view. You can also, for example, slightly curved outward. They are arranged substantially vertically and in particular exactly perpendicular to the longitudinal axis of the surfboard.

The back surface extends substantially over the entire width and in particular over the entire width of the surfboard. The tear-off edge forms its lower edge and also runs essentially over the entire width of the surfboard. It is possible that, for example, in the region of laterally arranged rear extensions, these exceed the width of the tear-off edge and / or the rear surface towards the outside.

The portion of the surfboard located above the rear surface extends at least in sections beyond the rear surface, thus projecting at least in sections beyond the trailing edge and the rear surface to the rear, thus forming a rear extension. The top of the surfboard thus protrudes at least in sections beyond the spoiler edge.

In this case, the part of the upper side, which extends beyond the tear-off edge, also further edges and / or surfaces, such as rear surfaces, have. In particular, it may have a transverse to the longitudinal direction of the surfboard edge with another at least partially facing back surface, so that in the rear area, the top of the surfboard is lower than in the front area. The trailing edge is suitable for the defined and efficient separation of the water from the sliding surface on the underside of the surfboard, since significantly less turbulence occurs. Thus, the sliding friction is reduced when sliding. The main advantage is that higher speeds are possible with the same drive power.

In one embodiment of the invention, the trailing edge is rounded and the radius of the rounding is in a range of 1 mm to 3 mm, in particular from 1, 2 mm to 2 mm. Typically, the radius of curvature is in the range of 1, 3 mm to 1, 8 mm.

By a relatively small radius of curvature, the surface tension of the water is disturbed and a clean demolition of the water from the sliding surface on the underside of the surfboard is made possible. The function of the spoiler edge is significantly improved. The fact that the radius of the trailing edge is greater than 1 mm, there is the additional advantage that a potential risk of injury by cuts on sharp edges is prevented.

In a further embodiment of the invention, the surfboard has a height H 1 and the rear surface has a height H2. The height H1 of the surfboard is measured in the side view in the region of the spoiler edge as the maximum, perpendicular to the longitudinal direction of the surfboard lying distance between the underside of the surfboard and the top of the surfboard.

The height H2 of the back surface is measured in the side view as lying perpendicular to the longitudinal direction of the surfboard distance between the bottom of the back extension of the surfboard, so the bottom of the over the spoiler edge backward extending portion of the surfboard, and the lowest point of the spoiler edge ,

The height H2 of the back surface extends in a portion of the over the spoiler edge extending beyond the top of the surfboard over 25% to 75%, in particular about 35% to 65%, the height H1 of the surfboard. In one embodiment, H2 in this section extends over 40% to 60% of H 1.

In a further embodiment of the surfboard, the upper side of the surfboard extends at least in sections by a length X beyond the trailing edge, wherein X is in a range of 5 cm to 50 cm, in particular 10 cm to 35 cm. The top may extend beyond the trailing edge in the entire width of the surfboard or in one or more sections. For example, Fishtails can be arranged on the rear of the surfboard right and left, which protrude beyond the back surface. These form then in the back area the surface of the surfboard. In between, the back surface forms the farthest point of the surfboard.

The length X, also referred to as the back supernatant, may in one embodiment be in the range of 15 cm to 25 cm.

In a further embodiment of the surfboard, this comprises two rear extensions, which extend beyond the spoiler edge at the top of the surfboard in its rear part.

The back extensions present in this embodiment are referred to as fishtails as described. They are in particular designed such that they can be immersed in lateral weight shift by tilting the surfboard about its longitudinal axis into the water and there generate additional water resistance. Thus, a change in direction for controlling the surfboard can be achieved.

In particular, the fishtails are formed substantially mirror-symmetrically to the longitudinal axis of the surfboard. Their width can be between 10% and 40% of the width of the surfboard and they can, for example, taper pointedly to the rear and be rounded at the edges.

In a further embodiment of the surfboard, the rear surface and the underside form a common angle β, which is in a range of 70 ° to 100 °, in particular 80 ° to 95 °. In one embodiment, the angle β may be substantially and in particular exactly a right angle.

The angle ß is the angle between the back surface and the underside of the surfboard at the trailing edge. A forwardly inclined surface can have a positive effect on the effectiveness of the spoiler lip, but under certain circumstances is more difficult to implement in terms of manufacturing technology.

In one embodiment, the angle β is between 90 ° and 100 °, in particular 90 °, and the main body of the surfboard is produced in a negative mold. This has the advantage that in addition to the function of the tear-off edge, the surfboard can be removed from it during manufacture without destroying the mold.

In one embodiment of the surfboard, this comprises on the underside, on both sides of a longitudinal axis of the surfboard in the longitudinal direction of the surfboard, at least one first guide surface and at least one first intermediate surface, wherein the first intermediate surface lies between the central longitudinal axis and the first guide surface. Furthermore, the surfboard comprises on the underside, on both sides of the central longitudinal axis, at least one first leading edge extending substantially parallel to the central longitudinal axis of the surfboard, the first leading edge having a cut edge of the first guide face with the first intermediate face is. The first guide surface and the first intermediate surface form a first angle γ which lies in the range of 50 ° to 150 °, in particular 70 ° to 140 °. In one embodiment, the angle γ is between 75 ° and 135 °.

The first leading edge lies between the first guide surface and the first intermediate surface. The described surfaces are arranged on the underside of the surfboard. They form a common cutting edge, which is the first leading edge. The first leading edge thus lies between the first guide surface and the first intermediate surface on the underside of the surfboard.

There are on each side of the underside of the surfboard, so on the intended use in the direction of travel right and left side of the central longitudinal axis, at least one guide surface, at least one Zwischenfiäche and arranged at least one leading edge.

Typically, but not necessarily, the guide surface and the leading edge are arranged such that no undercut occurs with respect to the vertical extension direction of the surfboard.

The leading edge and the adjacent guide surface are arranged in a part of the total length of the surfboard. In particular, they extend over 30% to 90% of the total length of the surfboard and in one embodiment over 40% to 70% of the total length of the surfboard.

It is possible for the guide surfaces and / or interfaces to taper or shrink forward so that the shape of the underside of the surfboard approximates to a smooth underside. The leading edges can experience towards the front, for example, an upward curvature.

The tear-off edge typically extends beyond the end faces of the guide surfaces, which form part of the rear surface, thereby encompassing the ends of the guide edges. It is not excluded that one or more leading edges and / or guide surfaces do not extend to the tear-off edge.

The leading edges are outer edges, so protruding edges. The edges delimiting the guide surfaces on the opposite sides of the guide edges are accordingly formed as inner edges.

In particular, the guide surfaces are arranged such that they limit the surfboard on the underside to the outside and at least with a vertical component of their orientation laterally inflowing water can be discharged to the outside. The surface normals of the guide surfaces face away from the central axis of the surfboard and typically obliquely downward. If the surfboard is used as intended the leading edges are typically oriented at an angle of 0 ° to 50 ° to the vertical.

The guide surfaces typically have a width between 1 cm and 30 cm, in particular between 2 cm and 20 cm. A longitudinally aligned corrugation or a fine structuring of the surface in particular does not provide any guide surfaces or guide edges in the sense of the invention.

Of course, further guide edges and / or guide surfaces can be arranged on the surfboard beyond. In addition, the underside of the surfboard can also be subdivided further, resulting in further surfaces and / or edges.

By the early discharge of water to the outside, on the one hand, a lighter and faster transition from displacement at slow speeds to gliding at higher speeds is possible. On the other hand, straight-ahead driving is stabilized without the use of overhanging elements such as fins. This is made possible by the vertical component of the guide surfaces. This has the property to convert laterally inflowing water in a forward movement

Since the surfboard has no fin, it has significant advantages during transport, since Finns often experience damage as cantilevered and particularly delicate elements. Furthermore, a surfboard without fin again has less water resistance.

In a further embodiment of the surfboard, this comprises on both sides between the first guide surface and the respective outer edge of the surfboard at least one second guide surface and at least one second intermediate surface, wherein the second intermediate surface lies between the first guide surface and the second guide surface. Furthermore, the surfboard comprises on both sides between the first guide surface and the respective outer edge of the surfboard at least one second leading edge, wherein the second leading edge is a cutting edge of the second guide surface with the second intermediate surface. The second guide surface and the second intermediate surface form a second angle γ ', which is in the range of 50 ° to 150 °, in particular 70 ° to 140 °. In one embodiment, the angle γ 'is between 75 ° and 135 °.

The second leading edge with the angle γ 'and the second guide surface are formed in particular analogous to the first leading edge with the angle γ and the first guide surface on the underside of the surfboard. Of course, the angles and the dimensions of the surfaces can be different.

Of course, further guide edges and / or guide surfaces can be arranged on the surfboard beyond. A significant advantage is that the second guide surface and the second leading edge further increase the tracking stability of the surfboard and divert water to the sides, which reduces the sliding friction and allows higher speeds.

In a further embodiment of the surfboard, this comprises on both sides between the second guide surface and the respective outer edge of the surfboard arranged at least a third guide surface and at least a third intermediate surface, wherein the third intermediate surface between the second guide surface and the third guide surface. Furthermore, the surfboard comprises on both sides between the first guide surface and the respective outer edge of the surfboard at least a third leading edge, wherein the third leading edge is a cutting edge of the third guide surface with the third intermediate surface. The third guide surface and the third intermediate surface form a second angle γ "which lies in the range of 50 ° to 150 °, in particular 70 ° to 140 °. In one embodiment, the angle γ 'is between 75 ° and 135 °.

The third leading edge with the angle γ "and the third guide surface are formed in particular analogously to the first and / or second leading edge with the angles γ and / or γ 'and to the first and / or second guide surface on the underside of the surfboard Of course, dimensions of the surfaces can be different.

Of course, further guide edges and / or guide surfaces can be arranged on the surfboard beyond.

The essential advantage is that the third guide surface and the third leading edge further increase the tracking stability of the surfboard, even earlier to divert the inflowing water to the sides and prevent flow of laterally inflowing water under the surfboard or implement them in propulsion. This allows even higher speeds in curves.

In a further embodiment, the first guide surface has an angle 51 to a vertical and the second guide surface has an angle 52 to the vertical and the first intermediate surface has an angle ε1 to a horizontal and the second intermediate surface has an angle ε2 to the horizontal on. Here, the angle 52 is smaller than the angle 51 and / or the angle ε2 is greater than the angle ε1.

In other words, the second guide surface, viewed in cross-section and when used as intended, is steeper than the first guide surface and / or the second intermediate surface is steeper than the first intermediate surface.

In one embodiment, the angle 52 is smaller than the angle 51 and the angle ε2 is greater than the angle ε1. This allows an increase in efficiency in the discharge of water to the side.

In a further embodiment, the third guide surface has an angle 53 to the vertical and the third intermediate surface has an angle ε3 to the horizontal. Here, the angle 52 is smaller than the angle 51 and the angle 53 and / or the angle z2 is greater than the angle ε1 and the angle ε3.

In other words, the second guide surface, viewed in cross-section and when used as intended, is steeper than the first guide surface and the third guide surface and / or the second intermediate surface is steeper than the first intermediate surface and the third intermediate surface.

In one embodiment, the angle 52 is smaller than the angle 51 and the angle 53 and the angle ε2 is greater than the angle ε1 and the angle ε3.

Thus, the outer edges are flatter and thus favor a good handling of the surfboard.

The underside of the surfboard can be divided into four consecutive zones in the direction of travel, with the typically protruding from the water front, also referred to as Nose, is not counted. This covers about 10% to 30% of the total length of the surfboard. The first zone, behind the nose, covers about 8% to 20% of the total length and serves the directional stability and, together with the second zone, the early planing, ie the transition from displacement into gliding. The second zone comprises about 10% to 20% of the total length and here z. B. raise the leading edge from the bottom. The third zone is the main sliding area at high speeds, ie the area that touches the water. This covers about 30% to 50% of the total length and is bounded at its rear end by the spoiler lip. This is followed by the fishtails, zone 4, which make up about 3% to 10% of the total length and are used as described for shifting weight, tilting the surfboard and dipping the fishtails into the water for steering.

In a further embodiment of the surfboard, this has a total length L which is in the range of 1.80 m to 2.50 m, in particular 2.10 m to 2.49 m. In one embodiment, the total length L is between 2.30 m and 2.48 m.

A significant advantage of this design is that surfboards under 2.50 m total length in many areas do not require regulatory approval.

In a further embodiment of the surfboard, the underside comprises two partial surfaces arranged at an angle α, which form a common edge aligned along the longitudinal axis of the surfboard, the angle α being in the range of 130 ° to 180 °, in particular 160 ° to 179 °, is located. The angle may be in an embodiment in the range of 170 ° and 178 °.

In other words, the underside of the surfboard is subdivided into two parts which are essentially mirror-symmetrical and, in particular, exactly mirror-symmetrical with respect to the central longitudinal axis, forming an angle at their cutting edge which causes or reinforces a convex basic shape of the trunk.

A significant advantage is the position stabilization of the surfboard in the water. Furthermore, thus can be derived even easier and early water to the outside, which allows a lighter and faster transition from displacement into sliding.

In a further embodiment of the surfboard, this comprises a motor-driven drive.

The engine may in particular be an electric motor. However, an internal combustion engine, such as a gasoline engine, or any other engine is possible.

In particular, the drive may be configured as a jet drive, also called a water jet drive. However, for example, a marine propeller, also referred to as a propeller, possible.

In a further embodiment of the surfboard of the motor-driven drive is designed as a water jet drive, wherein in particular two water jet engines are arranged on the rear surface and substantially mirror-symmetrical to the longitudinal axis of the surfboard.

It is at least a jet propulsion, which sucks in water and expels accelerated again, arranged on the surfboard. In particular, two jet engines are arranged in mirror symmetry, because this stabilizes the straight ahead compared to the central arrangement of a single jet engine.

In particular, the jet engine is electrically operated, but also any other engine is possible. In an electrically operated motor, the surfboard includes in particular the battery or the rechargeable battery, which is protected in a suitable manner from penetrating water.

The suction region or the suction regions of the jet drive are arranged in particular in the rear region of the underside at this. Thus, even at higher speeds, when the front part of the surfboard protrudes from the water, water can be sucked. With the combination of two mirror-symmetrically arranged water jet drives with the described underside subdivided in sub-areas, another advantage is that, due to the angled arrangement of the sub-areas, the intake areas of the jet drives are further apart or have less overlapping areas. In this case, the jet engines have a higher efficiency.

The invention is not limited to the alternatives presented here. All described embodiments and examples can be combined with each other.

The invention will be explained below with reference to the embodiments illustrated in the accompanying drawings.

Show it

1 is a plan view of the underside of the invention surfboard,

Fig. 2 shows a cross section of a surfboard according to the invention in the region of the rear surface, as well

Fig. 3 is a side view of the rear portion of a surfboard according to the invention.

Figure 1 shows a plan view of the bottom 12 of the surfboard 10 according to the invention with its main movement direction 16. The tear-off edge 20 is arranged in the rear region of the surfboard 10, which is shown on the right in the image. It forms the conclusion of the bottom 12 of the surfboard 10. Above the tear-off edge 20, the rear surface extends 22. In addition, to the rearmost point of the surfboard 10, two rear extensions extend 24 in the form of two fishtails. These can be immersed in lateral weight shift by tilting the surfboard 10 into the water and there generate additional water resistance. Thus, a change in direction for controlling the surfboard 10 can be achieved.

The underside 12 is divided into two symmetrically arranged right and left along the central longitudinal axis partial surfaces forming an angle α (not shown here). Furthermore, a first guide edge 30, a second guide edge 30 'and a third guide edge 30 "are arranged in the rear area of the underside 12 of the surfboard 10. These are arranged on both sides of the central longitudinal axis in the direction of the outer edges and run essentially along the longitudinal extension direction of the Surfboards 10. They have a slight curvature towards the outer edge of the surfboard 10 and extend over about half of the Total length of the surfboard 10. In the direction of the central longitudinal axis adjacent to the first guide edge 30, the first intermediate surface 33 is arranged.

Furthermore, flow paths 60 of the water are shown. It is clear that under the middle part of the bottom 12 of the surfboard 10, the water flows straight through. On the other hand, water flowing laterally from the central axis is directed outwardly from the inclined first intermediate surface 33. Further inflowing water is discharged by means of the guide edges 30, 30 'and 30 "very quickly to the outside.

2 shows a cross-section of a surfboard 10 according to the invention in the area of the rear surface 22. As can be seen, the rear surface 22 makes up a large part of the cross-sectional area of the surfboard 10. Centrally arranged and mirror-symmetrical with respect to a central longitudinal axis two water jet engines 50 are arranged, which allow a stable straight ahead in this arrangement.

Right and left at the top 14 rear extensions 24 are shown, executed as fishtails.

The underside 12 has a central edge 42, on which the abutting partial surfaces form an angle α. This is about 174 °.

On both sides, a first guide edge 30 is arranged, which forms the cutting edge of a slightly curved executed first intermediate surface 33 with the first leading edge 32. The angle γ present here is an obtuse outer angle and is approximately 1 10 °. The first guide surface 32 has obliquely outside and below, so that they can dissipate laterally inflowing water.

A second intermediate surface 33 'adjoins the first guide surface 32 at an inner angle, which forms a common cutting edge, namely the second leading edge 30', with a second guide surface 32 '. The angle γ 'present here is an acute external angle and is approximately 75 °.

To the second guide surface 32 'includes in an inner angle in each case a third intermediate surface 33', which is oriented approximately horizontally. This forms with a further outward third guide surface 32 "a common cutting edge, namely the third leading edge 30". The angle γ "applied here is an obtuse outer angle and is approximately 135 °.

The tear-off edge 20 lies in the intersection region of the underside 12 with the rear-side surface 22 and here comprises all guide surfaces, guide edges and intermediate surfaces. It covers about 90% of the width of the surfboard. The third guide surface 32 "protrudes almost to the outer edge of the surfboard and is in their width only by the Fishtails surpassed. The height H2 of the rear surface 22 extends in about more than 50% of the height H1 of the surfboard 10.

3 shows a side view of the rear region of a surfboard 10 according to the invention with its main movement direction 16. In this illustration, the tear-off edge 20 can be seen, which forms the cut edge between the underside 12 and the rear surface 22. The surfaces mentioned abut each other here at an angle β of 90 °. On the right in the image, the rear extensions 24, executed as fishtails, can be seen, which extend beyond the tear-off edge 20 and the rear-side surface 22. The top 14 of the surfboard 10 extends in the region of the rear extensions 24 to the rearmost point of the surfboard 10th

On the underside 12 are the first leading edge 30, the second leading edge 30 ', the third leading edge 30 "and the first guide surface 32, the second guide surface 32' and the third guide surface 32" visible.

LIST OF REFERENCE NUMBERS

Surfboard 10

Bottom 12

Top 14

Principal movement 16 tear-off edge 20 rear surface 22 rear extension 24 first leading edge 30 second leading edge 30 'third leading edge 30 "first angle Y second angle Y ^' third angle Y" first guide surface 32 second guide surface 32 'third guide surface 32 "first interface 33 second interface 33 ^' third intermediate surface 33 "angle Q angle ß common edge of the partial surfaces 42nd

Waterjet engines 50

Flow paths 60

Claims

Patent claims

1 . Surfboard (10), comprising a bottom (12), a top (14), a rear surface (22), and a tear-off edge (20) lying essentially perpendicular to a longitudinal direction of the surfboard (10),

wherein the tear-off edge (20) is formed by a cutting edge between the underside (12) and the rear surface (22),

characterized in that the top (14) of the surfboard (10) extends at least in sections beyond the tear-off edge (20) in a rear part of the surfboard (10).

2. Surfboard (10) according to claim 1, characterized in that the tear-off edge (20) is rounded and the radius of the rounding is in a range of 1 mm to 3 mm, in particular 1.2 mm to 2 mm.

3. Surfboard (10) according to at least one of claims 1 and 2, wherein the surfboard (10) has a height H1 and the rear surface (22) has a height H2, characterized in that the height H2 of the rear surface (22 ) in a section of the top (14) of the surfboard (10) extending beyond the tear-off edge (20) over 25% to 75%, in particular over 35% to 65%, of the height H 1 of the surfboard (10).

4. Surfboard (10) according to at least one of claims 1 to 3, wherein the top (14) of the surfboard (10) extends at least in sections by a length X beyond the tear-off edge,

characterized in that X is in a range from 5 cm to 50 cm, in particular 10 cm to 35 cm.

5. Surfboard (10) according to at least one of claims 1 to 4, comprising two rear extensions (24), in particular fishtails,

characterized in that the rear extensions (24) extend beyond the tear-off edge (20) on the top side (14) of the surfboard (10) in its rear part, in particular symmetrically to the longitudinal axis of the surfboard (10).

6. Surfboard (10) according to at least one of claims 1 to 5, wherein the rear surface (22) and the underside (12) form a common angle β, characterized in that β in a range of 70 ° to 100 °, in particular 80° to 95°.

7. Surfboard (10) according to at least one of claims 1 to 6, comprising on the underside (12), on both sides of a longitudinal axis of the surfboard (10) lying centrally in the longitudinal direction of the surfboard (10),

at least one first guide surface (32),

- at least one first intermediate surface (33), the first intermediate surface (33) lying between the central longitudinal axis and the first guide surface (32), and

at least one essentially parallel to the central longitudinal axis of the

Surfboard (10) extending first guide edge (30), the first guide edge (30) being an intersection edge of the first guide surface (32) with the first intermediate surface (33),

characterized in that the first guide surface (32) and the first intermediate surface (33) form a first angle γ, and γ is in the range from 50° to 150°, in particular 70° to 140°.

8. Surfboard (10) according to claim 7, comprising at least one second guide surface (32 ') arranged on both sides between the first guide surface (32) and the respective outer edge of the surfboard,

- at least one second intermediate surface (33'), the second intermediate surface (33') lying between the first guide surface (32) and the second guide surface (32'), and

at least one second leading edge (30'), wherein the second leading edge

(30') is an intersection edge of the second guide surface (32') with the second intermediate surface (33'),

characterized in that the second guide surface (32) and the second intermediate surface (33') form a second angle γ', and γ' is in the range from 50° to 150°, in particular 70° to 140°.

9. Surfboard (10) according to claim 8, comprising at least one third guide surface (32") arranged on both sides between the second guide surface (32 ') and the respective outer edge of the surfboard,

- at least one third intermediate surface (33 ^" ), the third intermediate surface (33") lying between the second guide surface (32') and the third guide surface (32"), and - at least one third guide edge (30"), the third guide edge (30") being an intersection edge of the third guide surface (32") with the third intermediate surface (33"),

characterized in that the third guide surface (32") and the third intermediate surface (33") form a second angle γ", and γ" is in the range from 50° to 150°, in particular 70° to 140°.

10. Surfboard (10) according to claim 8, wherein the first guide surface (32) has an angle 51 to a vertical and the second guide surface (32) has an angle 52 to the vertical and the first intermediate surface (33) has an angle ε1 to a has horizontal and the second intermediate surface (33) has an angle z2 to the horizontal,

characterized in that the angle 52 is smaller than the angle 51 and/or that the angle z2 is larger than the angle ε1.

1 1 . Surfboard (10) according to claim 10, wherein the third guide surface (32") has an angle 53 to the vertical and the third intermediate surface (33") has an angle ε3 to the horizontal,

characterized in that the angle 52 is smaller than the angle 51 and the angle 53 and / or that the angle ε2 is larger than the angle ε1 and the angle ε3.

12. Surfboard (10) according to at least one of claims 1 to 11, wherein the surfboard has a total length L,

characterized in that L is in the range from 1.80 m to 2.50 m, in particular 2.10 m to 2.49 m.

13. Surfboard (10) according to at least one of claims 1 to 12, wherein the underside (12) comprises two partial surfaces arranged at an angle α, which form a common edge (42) aligned along the longitudinal axis of the surfboard (10), characterized that α is in the range from 130° to 180°, in particular 160° to 179°.

14. Surfboard (10) according to at least one of claims 1 to 13, characterized in that the surfboard (10) comprises a motor-driven drive.

15. Surfboard (10) according to claim 14, characterized in that the motor-driven drive is designed as a water jet drive, in particular two water jet engines (50) being arranged on the rear surface (22) and essentially mirror-symmetrically to the longitudinal axis of the surfboard (10).