Fin stabilizer, vibration damping member, and watercraft

Abstract

Disclosed are a fin stabilizer for roll stabilization of a watercraft, whose drive unit is connected to a ship structure in a vibration-damping manner, a vibration damping element and a watercraft.

Description

[0001] The invention relates to a fin stabilizer according to the preamble of claim 1, a vibration damping element and a watercraft.

[0002] Fin stabilizers are used to stabilize a watercraft while underway, at anchor, and / or to influence its course. Common fin stabilizers, such as pivoting stabilizers, have a stabilizer fin that, when at rest, is swung into a fin box. With fixed stabilizers, the stabilizer fin is always located outside the hull. In both types, the stabilizer fin can move up and down around its longitudinal axis when in operation.

[0003] Fin stabilizers, especially on larger watercraft, are typically electro-hydraulically driven. Purely electrically driven fin stabilizers are less common and invariably use mechanical gearboxes. The mechanical gearbox reduces the high speed of the electric motor to the low output speed required to drive the fin stabilizers, thus enabling the high output torques necessary for their operation.

[0004] Besides the drive unit (actuator) itself, the respective mechanical transmission also transmits vibrations into the ship's hull, which can put stress on the ship's structure. Furthermore, depending on the sector of the shipping industry, for example in yacht building, requirements regarding structure-borne noise levels caused by the rotating components of the ship's stabilizers are very high.

[0005] Furthermore, the stabilizer fin exerts forces on the other components of the stabilizer. These forces include bending moments, shear forces, normal forces, and torsional forces. However, components such as gearboxes require high precision with regard to, for example, alignment, component manufacturing, installation tolerances, and protection against such external loads.

[0006] The invention is therefore based on the objective of creating a fin stabilizer that enables at least a reduced transmission of vibrations into a ship's structure and also at least a reduced transmission of loads from the stabilizer fin into components in operative connection with the stabilizer fin. Furthermore, the invention aims to create a vibration damping element for such a fin stabilizer and a watercraft with at least a reduced level of structure-borne noise in the area of ​​its fin stabilizer.

[0007] This problem is solved by a fin stabilizer with the features of claim 1, by a vibration damping element with the features of claim 8, and by a watercraft with the features of claim 9. Advantageous embodiments are set forth in dependent claims 2 to 7.

[0008] A fin stabilizer according to the invention for stabilizing the roll of a watercraft has a stabilizer fin rotatably mounted about its longitudinal axis. The fin stabilizer has a drive unit for rotating the stabilizer fin or changing its angle of attack. The drive unit has a mounting section that can be attached to a hull wall in a rotationally secure manner via a corresponding connecting section. According to the invention, at least one vibration damping element is arranged between the drive-side mounting section and the hull-side connecting section, such that the mounting section is physically spaced apart from the connecting section. Thus, there is no direct physical contact between the mounting section and the connecting section, but rather indirect contact via the at least one vibration damping element.

[0009] A vibration damping element according to the invention for such a fin stabilizer has an outer part for connection to a drive-side mounting section and an inner part for connection to a ship's hull-side connection section, wherein one of the parts has vibration damping properties.

[0010] A watercraft according to the invention is equipped with such a fin stabilizer.

[0011] The at least one vibration damping element decouples the mounting section from the connection section, thus preventing or reducing structure-borne noise from the drive unit (actuator) from being transmitted into the ship's structure. Furthermore, the at least one vibration damping element reduces the stress on the components that are in operative contact with the stabilizer fin.

[0012] In a preferred embodiment, a plurality of vibration damping elements are provided. This measure creates redundancy, ensuring the performance and safety of the fin stabilizer in the unlikely event of a defect or failure of one of the vibration damping elements. For example, the vibration elements are evenly distributed around the circumference of the mounting section and the connection section.

[0013] In particular, each vibration damping element can have an outer part that is detachably connected to the mounting section and an inner part that is detachably connected to the connection section. This allows each part to be optimally adjusted with regard to its material and shape.

[0014] In a preferred embodiment, the outer part is made of a harder material than the inner part. For example, the outer part can be a metal ring that surrounds the inner part, which may be elastomer-based, and is firmly embedded within it.

[0015] Preferably, each vibration damping element is positioned in a receptacle of the mounting section. This allows for optimal design and connection of each vibration element to the mounting section, as collisions with adjacent vibration damping elements are prevented. The receptacles are, for example, through-holes or bores that can be easily integrated into the mounting flange during manufacturing. The alignment of the mounting section to the connection section can be simplified if the connection section has a corresponding number and orientation of mating receptacles.

[0016] Replacing vibration damping elements, for example during maintenance or inspection, can be simplified if they can be individually removed without disassembling the assembly section.

[0017] In particular, the outer parts of the vibration damping elements and the openings can have a rotationally asymmetrical outer or inner contour, so that the vibration damping elements can only be positioned in or removed from the openings by a rotary-sliding motion. For this purpose, the outer parts can, for example, have an oval or diamond-shaped outer contour. The openings of the mounting section then have a corresponding oval or diamond-shaped inner contour, so that after insertion and rotation of the vibration damping elements, their outer parts overlap the mounting section in sections. The vibration damping elements are then connected to the mounting section in the area of ​​overlap.

[0018] Preferred embodiments of the fin stabilizer according to the invention will be explained in more detail below with reference to highly simplified figures. These show Figure 1: a partial longitudinal section through a fin stabilizer of a watercraft according to the invention, Figure 2: a perspective front sectional view of a first embodiment of the fin stabilizer, Figure 3: a perspective rear sectional view of a first embodiment of the fin stabilizer, and Figure 4: a sketchy representation of a partial overlap of an inserted vibration damping element with a mounting section receiving it of a second embodiment of the fin stabilizer.

[0019] In Figure 1 Figure 1 shows a longitudinal section of a fin stabilizer 1 according to the invention. The fin stabilizer 1 is used to stabilize the roll of a watercraft such as a cargo ship or yacht while underway or at anchor.

[0020] The fin stabilizer 1 essentially comprises a stabilizer fin 2 with a fin shaft 4 and a drive unit 6. Furthermore, the fin stabilizer 1 includes a coupling (not shown), a locking device for securing the stabilizer fin in its current angle of attack, and a control and regulating device (not shown).

[0021] The stabilizer fin 2 is connected to an output shaft of the drive unit 6 via the fin shaft 4 and the coupling by positive, force, and / or frictional engagement. The coupling is, for example, a clamping coupling or a steel multi-plate clutch, and the output shaft, in the example shown here, is a gearbox output shaft of a gearbox 8 of the drive unit 6. The drive of the drive unit 6 can be, for example, hydraulic or purely electric, such as an electric motor. The gearbox 8 is interposed between the drive and the drive. However, it is also conceivable to dispense with the gearbox 8 entirely, for example, if the electric motor is a high-torque synchronous motor with a high number of poles.

[0022] The fin shaft 4 is guided through a tube 10 and rotatably mounted within it about its longitudinal axis by means of bearings (not shown). An example of such a bearing is a rolling element bearing and a watertight sliding bearing. The rolling element bearing is, for example, a double-row skewed barrel bearing and is located away from the water, i.e., near the coupling. The sliding seal is located near the water, i.e., away from the coupling. It prevents seawater from penetrating an unnumbered annular space between the tube 10 and the fin shaft 4 and thus protects the rolling element bearing from water.

[0023] The hull tube 10 itself is guided axially through a support tube 12, which penetrates a section of an outer skin or hull wall 14 on the water side and is securely connected to it in a rotationally fixed manner, in particular by welding. With its end facing inwards, the support tube 12 forms a flange 16 to which the hull tube 10 is connected by an outer shoulder 18, for example by bolting.

[0024] To connect the drive unit 6, here the gearbox 8, to the rotationally secured tube 10, the latter has a connection flange 20 at its inner end. The gearbox 8 has a corresponding mounting flange 22. The connection is made via a multitude of two-part screw connections.

[0025] According to the invention, the assembly section 22 and the connection section 20 are not in direct contact with the body, but rather via a plurality of vibration damping elements 24 arranged between them, as spacers. Each screw connection is assigned a vibration damping element 26.

[0026] Exemplary vibration damping elements 26 including the screw connections are shown in the Figures 2 and 3 depicted.

[0027] The vibration damping elements 26 are identical in design. Each vibration damping element 26 has an outer part 28, which rests against the mounting flange 22 from the rear (first screw connection part), and an inner part 28, which axially penetrates the openings 30 (here circular bores) of the mounting flange 22 and is penetrated by an axial fastening screw 32, which engages in a corresponding internal threaded bore 34 of the connecting flange 20 (second screw connection part). In the screwed-in state, each vibration damping element 26 is clamped via the threaded engagement between the fuselage-side connecting flange 20 and a respective screw head 36, so that the vibration damping elements 26 are pressed against the connecting section 20 with their respective inner part 28.Preferably, washers (not shown) are arranged under the screw heads 36 to ensure uniform application of a screw force, completely covering the inner parts 28 on the front side.

[0028] The respective outer part 26 is in the Figures 2 and 3 In the illustrated embodiment, a ring flange is attached to the rear of the mounting flange by means of a plurality of screws (not shown). Preferably, the outer part 26 is made of a harder material than the inner part 28. Examples of hard or harder materials are metals or metallic alloys.

[0029] The inner part 28, viewed from front to back (from the mounting section 22 towards the connecting flange 20), has a conically widened shape. The outer parts 26 are arranged at its radially widest point. The outer parts 26 each surround the inner parts 28 and are integrally connected to them, for example, by gluing or casting. The inner parts 28 are made of a softer material than the outer parts 26. The material of the inner parts 28 has a damping effect. Examples of rubber-like materials are elastomers such as rubber.

[0030] To enable the screw connection of the vibration damping elements 24 to the mounting flange 22, their respective outer part 26 (ring flange) has an outer diameter that is larger than the inner diameter of the circular openings 30. To disassemble individual vibration damping elements 24, the following applies: Figures 2 and 3In the illustrated embodiment, for example during an inspection, the entire mounting flange 22 and thus the entire gearbox must be removed. This means that in order to remove one vibration damping element 24, all vibration damping elements 24 must be removed.

[0031] An embodiment in which the vibration damping elements 24 according to the invention can be individually removed and installed from the front with the mounting section 22 (mounted gearbox) already installed, is shown in Figure 4 hinted at.

[0032] The passages 30 in the assembly section 22 and the outer parts 26 of the vibration damping elements 24 do not have a rotationally symmetrical contour (as in the embodiment according to the Figures 2 and 3), but rather contours such that the outer parts 26 can only be inserted axially through the openings 30 in a specific first orientation and can only be brought into rear contact with the mounting flange 22 in a specific second orientation, which differs from the first orientation. In other words, after the outer parts 26 have been inserted through the openings 30, the outer vibration damping elements 24 must be rotated about their longitudinal axis to achieve an overlap between the outer parts 26 and the mounting section 22, so that screwing can take place in the area of ​​overlapping body sections. In the embodiment shown here, the openings 30 have an oval inner contour and the outer parts 26 have a corresponding oval outer contour. Exemplary alternative contours are diamond-shaped contours.

[0033] Disclosed are a fin stabilizer for roll stabilization of a watercraft, whose drive unit is connected to a ship structure in a vibration-damping manner, a vibration damping element and a watercraft. Reference symbol list

[0034] 1 Fin stabilizer 2 Stabilizer fin 4 Fin shaft 6 Drive unit 8 Gearbox 10 Cooler tube 12 Support tube 14 Fuselage wall 16 Flange (cooler tube) 18 Outer shoulder (support tube) 20 Connection flange / section (fuselage side) 22 Mounting flange / section (drive side) 24 Vibration damping element 26 Outer part 28 Inner part 30 Passage 32 Mounting screw 34 Internal threaded hole 36 Screw head

Claims

1. Fin stabilizer (1) for roll stabilization of a watercraft, comprising a rotatably mounted stabilizer fin (2) and a drive unit (6) for changing an angle of attack of the stabilizer fin (2), wherein the drive unit (6) has a mounting section (22) which can be attached to a connection section (20) on a hull wall, characterized by the fact that between the drive-side mounting section (22) and the fuselage-side connection section (20) at least one vibration damping element (24) is arranged such that the mounting section (22) is physically spaced away from the connection section (20).

2. Fin stabilizer according to claim 1, wherein a plurality of vibration damping elements (24) are provided.

3. Fin stabilizer according to claim 2, wherein the vibration damping elements (24) are detachably connected to the mounting section (22) with an outer part (26) and to the connecting section (20) with another inner part (28).

4. Fin stabilizer according to claim 3, wherein the outer part (26) is made of a harder material than the inner part (28).

5. Fin stabilizer according to claim 2, 3 or 4, wherein the vibration damping elements (24) are inserted through openings (30) of the mounting section (22).

6. Fin stabilizer according to one of claims 2 to 5, wherein the vibration damping elements (24) are individually removable when the mounting section (22) is installed.

7. Fin stabilizer according to claim 6, wherein the outer parts (26) of the vibration damping elements (22) and the passages (30) have a rotationally asymmetric outer and inner contour, respectively.

8. Vibration damping element (24) for a fin stabilizer (1) according to one of the preceding claims, comprising an outer part (26) for connection to a drive-side mounting section (22) and an inner part (28) for connection to a ship-hull-side connection section (20), wherein one of the parts (28) has vibration damping properties.

9. Watercraft with a fin stabilizer (1) according to any one of claims 1 to 7.

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