Rudder post for rudders for water vehicles

The rudder post (40) for rudders for water vehicles has end sections (41, 42) made of a metallic material, in particular of wrought iron, and a mid post section (45) made of a nonmetallic material connected with the end sections so that the rudder post has a relatively low weight even for a very big length by maintaining a high flexural strength and torsion stiffness.

This invention relates to a rudder post for rudders for water vehicles.

Rudder posts for rudders of water vehicles are mainly made of wrought iron. If rudder posts with a big length are to be forged, there are difficulties as far as only a very small number of forges with a corresponding capacity are available and the orders of rudder posts, in particular with a length over 10 m, mostly verge on the capacity of these forges. Add to this that such rudder posts which are long and often have also a big diameter have a high weight which often exceeds the 100 t limit. This requires again particular constructions of the positioning and suspension of the rudder blade on the rudder post.

Thus, the aim of this invention is to create a rudder post which has a low weight by being big and which is partly made of a metallic material, in particular of wrought iron, so that a high flexural strength and torsion stiffness nevertheless remains maintained.

This aim is achieved with a rudder post according to the above described type with the characteristics indicated in claim1.

Accordingly, the invention consists in that the rudder post has end sections made of a metallic material, in particular of wrought iron, and a mid section made of a nonmetallic material connected with the end sections.

According to a preferred embodiment of the invention, the mid section of the rudder post made of a nonmetallic material is made of a carbon fiber composite material or of carbon fibers, preferably of graphite fibers.

Moreover, the invention provides that both end sections of the rudder post made of wrought iron are provided at their front sides turned to each other with neck-type reduced journal-shaped sections, the peripheral surfaces of which are provided with structures as adhesive surfaces for the mid section made of carbon fibers which surround the journal-shaped sections in form of windings, whereby the carbon fibers are coated and filled with a cast resin in the whole winding area which extends over the length of the mid section.

Further advantageous configurations of the invention are the subject of the subclaims.

The configuration of the rudder post according to the invention brings the advantage that rudder posts with a big length, a big diameter and a high weight can be manufactured for rudders of water vehicles without a fabrication of the whole rudder post of wrought iron being necessary because only the end sections of the rudder post are made of wrought iron while the mid section of the rudder post which is situated between the end sections is made of a nonmetallic material, in particular of a carbon fiber composite material or of carbon fibers, preferably of graphite fibers, which form the mid post section of the rudder post in form of windings, whereby the windings of the carbon fiber composite material or of the carbon fibers extend into the opposite ends of the end sections of the rudder post and are fixedly connected with these end sections. In this way, a rudder post is created, the end sections of which are made of wrought iron and can thus be exposed to the highest loads. Moreover, the end sections of the rudder post made of wrought iron receive the bearings for the positioning of the rudder post in port bearing for the rudder post.

For the embodiments shown inFIGS. 1 and 2,10designates a hull,20a rudder port bearing with its ends20a,20b,30a rudder blade and40a rudder post.

The rudder port bearing20configured as cantilever beam is fixedly connected with its upper end20awith the hull10and has an inner bore25which receives the rudder post40. The rudder port bearing20penetrates into the rudder blade30which is fixedly connected with the free lower end20bof the rudder post40guided through the inner bore25of the rudder port bearing20. The preferably cylindrical taper35formed in the rudder blade30for receiving the free end20bof the rudder port bearing20is limited by a lateral planking36,37(FIG. 2).

For the positioning of the rudder post40, the rudder port bearing20has at least one bearing. For the embodiment shown inFIG. 2, two bearings70,71are provided, namely an inner bearing70and an outer bearing71, whereby the bearing70is configured on the inner wall face of the rudder port bearing20and the other bearing71on the outer wall face of the rudder port bearing or on the inner wall face of the bearing provided on the rudder blade30.

The rudder post40positioned in the rudder port bearing20is configured in such a manner that its both end sections41,42are made of wrought iron, whereas the mid post section45is made of a nonmetallic material, in particular of a carbon fiber composite material or of carbon fibers, preferably of graphite fibers (FIG. 3). By wrought iron, an iron with a carbon content below 0,6% is understood.

Different constructive configurations can be provided for the fixing of the mid post section45of the rudder post40. As the embodiment according toFIG. 4shows, the front sides opposed to each other of both end sections41,42have journal-shaped sections51,52which are preferably provided with an outer wall structure51a,52ain order to guarantee the grip and the support of the mid post section45made of carbon fibers. Preferably the carbon fibers or the carbon fiber composite material are fixed on the journals51,52of the end sections41,42by windings60, whereby the windings extend over the periphery of both journals51,52and over the whole length of the mid post section45. For increasing the strength, the carbon fibers are covered or coated with a cast resin.

The configuration of the rudder post according to the invention is particularly advantageous in so far as very big lengths of rudder posts can be produced with a lowest weight. For a rudder post having for example a length of 10 m, the weight will be reduced by more than 50% compared to a rudder post which is completely made of wrought iron.

In one embodiment of the rudder arrangement the ratio of the length of the end section (41,42) and of the mid post section (45) of the rudder post (40) is ⅙ to ⅔.

A further embodiment provides that the rudder post40placed in the rudder port bearing20has material reinforcements80in the area of the bearings70,71placed in the rudder port bearing20, whereby preferably the material reinforcements80are provided in the area of the rudder port bearing end20b. These material reinforcements80are configured on the rudder post40preferably on the end section42of the rudder post40in the area of the inner bearing70provided on the rudder port bearing20(FIG. 2).

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