Dynamic fin comprising coupled fin sections

Abstract

A dynamic or aerodynamic fin comprising at least two parallel arranged fin sections. At least one fin section comprises a rotational axis for installing the fin section by a rotation shaft. An end stop is provided for stopping the rotational movement of the fin section to define an extreme position. In the extreme position the fin sections provide a substantially cambered shape to the fin. The dynamic fin is improved in that it comprises a pair of coupling elements. A first fin section is coupled to a second adjacent fin section by a pair of a first and second coupling elements. The first coupling element is complementary to the second coupling element. The first coupling element is part of, preferably integral, with the first fin section and the second coupling element is part of, preferably integral, with the second fin section.

Description

BACKGROUND OF THE INVENTION[0001]The present invention relates to a dynamic fin which comprises at least two parallel arranged fin sections. An orthogonal coordinate system including a first, second and third axis can be defined, wherein the fin sections extend in a direction of the first axis. Generally, this first direction is also regarded as the longitudinal direction. At least one fin section comprises a rotational axis for installing the fin section by a rotation shaft in for example a mounting box. The rotational axis extends in the direction of the fin section and enables a rotational movement of the fin section. An end stop is provided for stopping the rotational movement of the fin section to define an extreme position. In the extreme position the fin sections provide a substantially cambered shape to the fin. This cambered shape improves the hydro- or aerodynamic properties of the fin. In the other extreme position the fin may foam a mirrored cambered shape in comparison ...

AI Technical Summary

Benefits of technology

[0008]A dynamic fin according to the invention comprises at least two parallel arranged fin sections. An orthogonal coordinate system including a first, second and third axis can be defined, wherein the fin sections extend in a direction of the first axis. Generally, this first direction is also regarded as the longitudinal direction, wherein the fin sections extend away from a base which may define a base plane including the second and third axis. The base plane may be flat. The third axis is generally regarded as an outward direction which extends away from the substantially smooth and flat outer surfaces of the fin. At least one fin section comprises a rotational axis for installing the fin section by a rotation shaft to for example a mounting box. The rotational axis extends in the direction of the fin section and enables a rotational movement of the fin section. An end stop is provided for stopping the rotational movement of the fin section to define an extreme position. In the extreme position the fin sections provide a substantially cambered shape to the fin. This cambered shape improves the hydro- or aerodynamic properties of the fin.

[0022]Further the invention relates to a watercraft, e.g. sailing ship or surfboard, provided with a dynamic fin according to the invention. The fin may be a keel, a rudder or a tunnel thruster. Generally, the fin according to the invention may be useful for applications, wherein the fin is susceptible to a interchanging positive or negative dynamic load. The fin according to the invention may typically replace conventional symmetrical fins. The fin according to the invention may provide the same effectiveness for opposite hydrodynamic loads.

Problems solved by technology

Such a pin-hole hinge construction between adjacent fin sections brings some problems.

A first problem relates to the manufacturing of the fin sections.

Especially, in an embodiment of the dynamic fin for a surfboard, wherein the pin-hole hinge has to be very small, it may be a major problem to manufacture the hinge because of a limited available space for machining tools to access the fin.

The construction of the pin-hole is rather detailed which complicates the manufacturing and the assembling of the components.

Those further operations increase production efforts and costs.

Another problem of the known hinge-construction is that it is susceptible for contamination.

An environment with dirt, sand or salt may cause a failure of the pin-hole hinge construction.

No springs or elastic materials are provided which would substantially increase the resistance from a nominal position to an extreme position.

Images