WO2009154449A1

WO2009154449A1 - Assembly comprising a rudder and a propeller

Info

Publication number: WO2009154449A1
Application number: PCT/NL2009/050349
Authority: WO
Inventors: Christiaan Bernhard Maat; Edwin Simon Van Buren
Original assignee: MARIFIN BEHEER BV
Current assignee: MARIFIN BEHEER BV
Priority date: 2008-06-17
Filing date: 2009-06-16
Publication date: 2009-12-23
Anticipated expiration: 2010-12-17
Also published as: CN102066193A; NL2001693C2; EP2285669A1; JP2011524307A; KR20110017909A

Abstract

An assembly for propelling and steering a vessel comprises a propeller as well as a rotor which is situated in the flow emanating from the propeller, which rudder comprises a rudder blade, a trim blade which is rotatably mounted on the rudder blade and control devices for the rudder blade and the trim blade. At the propeller hub, the rudder blade has a thickening in which at least part of the control device of the trim blade is accommodated.

Description

Assembly comprising a rudder and a propeller

The invention relates to an assembly for propelling and steering a vessel, comprising a propeller as well as a rudder which is situated in the flow originating from the propeller, which rudder comprises a rudder blade, a trim blade which is mounted rotatably on the rudder blade, and control devices for the rudder blade and the trim blade.

Such an assembly is known from EP-A- 170,919. Therein, the control device for the trim blade is provided on the upper side of the rudder. To this end, the rudder is provided with a housing which accommodates the control device, protected against the surrounding water. Since the control device is provided with two levers, which are coupled to one another by means of a steering rod, the housing has to be of a considerable width, which is greater than the width or thickness of the rudder blade. These relatively large dimensions of the housing impact negatively on the performance of the rudder, and increase the drag thereof.

It is therefore an object of the invention to provide an assembly of the type mentioned above which is of a more efficient design. This object is achieved in that the rudder blade is provided with a thickening at the propeller hub, which thickening accommodates at least part of the control device of the trim blade.

The assembly according to the invention also makes use of a thickened housing. However, this housing is situated in the wake of the propeller hub, and not in the flow emanating from the propeller blades. This location of the relatively thick housing in the wake of the propeller hub results in relatively low drag and even has a positive effect on the propulsion supplied by the propeller.

A further advantage from a structural engineering point of view can be obtained by rotatably mounting the rudder blade on a rudder shank which is fixedly connected to the hull of the vessel. Such a rudder shank is also known from the abovementioned European patent application. A rudder shaft is rotatably supported in this rudder shank. At the bottom end, the rudder shaft is attached to the rudder blade so as to operate the latter. According to the invention, the rudder shank is embodied to extend into the internals of the rudder blade. There, the lever of the rudder blade is coupled to the rudder shank.

The advantage of this embodiment is that the relatively rigid rudder shank extends approximately along half the height, or if desired over a greater height, through the rudder blade and thus contributes greatly to the stability of the rudder blade. The rudder blade itself, as well as the rudder shaft, can thus be relatively light without the desired strength and stiffness being compromised.

In this connection, the rudder blade is preferably embodied in such a manner that it is rotatably supported with respect to the rudder shank by means of an upper bearing on the upper side of the rudder blade and a lower bearing near the centre, viewed in the direction of the rudder shank, of the rudder blade. This lower bearing is preferably situated at the thickening.

The control device for the trim blade may comprise a lever which is connected to the rotary shaft of the trim blade as well as an operating rod which is coupled to the free end of the lever. The other end of the lever is coupled to the rudder shank, at an eccentric position with respect to the axis of this rudder shank.

The thickening preferably comprises a streamlined body. This streamlined body may extend into the trim blade. The thickening can have many different shapes, but is preferably torpedo-shaped. The thickening may project with respect to the longitudinal side of the rudder blade.

The invention also relates to a rudder for an assembly as described above, comprising a rudder blade, a rudder shank which can be attached to the hull of the ship, a rudder shaft which runs through the rudder shank and is rotatably mounted in the rudder shank by means of bearings, which rudder shaft is attached to the rudder blade by its bottom end, a trim blade which is rotatably mounted on the rudder blade and an operating mechanism of the trim blade which is coupled to the rudder shank, which rudder shank extends into the interior of the rudder blade.

A rudder of this type is also known from EP-B-170,919. According to the invention, the rudder blade is provided with a thickening which is situated between the top end and the bottom end of the rudder and which accommodates the operating mechanism of the trim blade.

Reference is made to the rudder which is disclosed in German patent application DE-A- 3,101,042. In this known rudder, the operating mechanism of the trim blade is also located between the upper side and the lower side of the rudder. However, the rudder is not provided with a thickening, so that the space for said operating mechanism is limited. There is also no rudder shank which extends into the rudder blade, so that the rudder shaft is subjected to great loads.

According to a further embodiment of the assembly, the curvature of the rudder blade on one side of the thickening thereof may be embodied in such a manner that it is opposite to the curvature of the rudder blade on the other side of the thickening, which curvatures are adapted to the direction of rotation of the propeller. By suitably choosing these curvatures, it is possible to achieve a reduction of the drag of the water flowing past the rudder. In addition, these curvatures may contribute to preventing cavitation.

The invention will be described below with reference to an exemplary embodiment which is illustrated in the figures: Fig. 1 shows a rudder according to the invention.

Fig. 2 shows an assembly according to the invention with the rudder from Fig. 1.

The rudder shown in Fig. 1 has a propeller blade 2 which can be operated by the rudder shaft 7. This rudder shaft 7 is rotatably mounted on the rudder shank 5 by means of an upper bearing 3 and a lower bearing 4, which rudder shank 5 is fixedly connected to the hull 6. The rudder trunk or rudder shank 5 is a rigid structural element which firmly supports the rudder blade 2 by means of the upper bearing 3 and the lower bearing 4 against transverse forces and the like. The propeller blade 2 as well as the rudder shaft 7 can thus be of a relatively light design with respect to such a load.

The top end of the rudder shaft 7 is connected to the steering machine 8 and the bottom end thereof is connected to the force introduction 9 in the rudder blade 2. Thus, the rudder blade 2 can be turned into the desired position by means of the steering machine 8.

On the rear side of the rudder blade 2, the trim blade 10 is mounted so as to be rotatable about the shaft 11. A lever 12 is connected to the shaft 11. By means of the operating rod 13, this lever 12 is coupled to the eccentric 14 which is fixedly connected to the rudder shank 5. These operating means 12-14 of the trim blade 10 are largely situated in the torpedo-shaped thickening 15 which is located approximately in the centre of the height of the propeller blade 2.

Fig. 1 also shows the propeller 16. This propeller 16 has a propeller hub 17 and propeller blades 18. The propeller hub is at the same level as the thickening 15 of the propeller blade 2, so that the performance of the combination consisting of the propeller 16 and the rudder 1 is as good as possible.

In the cross section from Fig. 2, the embodiment of the control device 12-14 of the trim face 10 is illustrated at various angular positions. Due to this embodiment, the trim face 10 has a larger angular deflection than the rudder blade 2, and thus significantly reinforces the action of the rudder. The control device 12-14 of the trim blade 10 is situated in the torpedo-shaped thickening 15 which is aligned with respect to the propeller hub 17, so that the thickening 15 causes hardly any flow losses. The thickening 15 projects with respect to the longitudinal sides of the rudder blade 2, and continues into the trim blade 10 at reference numeral 19.

Claims

1. Assembly for propelling and steering a vessel, comprising a propeller (16) as well as a rudder (1) which is situated in the flow emanating from the propeller (16), which rudder (1) comprises a rudder blade (2), a trim blade (10) which is mounted rotatably on the rudder blade (2) and control devices (7, 8; 12-14) for the rudder blade (2) and the trim blade (10), characterized in that the rudder blade (2) has a thickening (15) at the location of the propeller hub (17), said thickening (15) accommodating at least part of the control device (12-14) of the trim blade (10).

2. Assembly according to Claim 1, wherein the control device (12-14) for the trim blade (10) comprises a lever (12) which is connected to the rotary shaft (11) of the trim blade (10) as well as an operating rod (13) which is coupled to the free end of the lever (12).

3. Assembly according to Claim 2, wherein the rudder (1) comprises a rudder shank (5) which is attached to the hull (6) of the vessel and with respect to which the rudder blade (2) is rotatably mounted, a rudder shaft (7) which runs through the rudder shank (5), said rudder shaft (7) being attached to the rudder blade (2) at its bottom end, wherein the rudder shank (5) extends into the rudder blade (2) and the operating rod (13) of the trim blade (10) is eccentrically coupled to the rudder shank (5).

4. Assembly according to Claim 3, wherein the rudder shaft (7) is rotatably supported with respect to the rudder shank (5) by means of an upper bearing (3) on the upper side of the rudder shank (5) and a lower bearing (4) near the lower side of the rudder shank (5).

5. Assembly according to one of the preceding claims, wherein the lower bearing (4) is situated at the thickening (15).

6. Assembly according to one of the preceding claims, wherein the thickening (15) comprises a streamlined body.

7. Assembly according to Claim 6, wherein the streamlined body (15) extends into the trim blade (10).

8. Assembly according to one of the preceding claims, wherein the thickening (15) is torpedo-shaped.

9. Assembly according to one of the preceding claims, wherein the thickening (15) projects with respect to the longitudinal sides of the rudder blade (2).

10. Assembly according to one of the preceding claims, wherein the curvature of the rudder blade (2) on one side of the thickening (15) thereof is opposite to the curvature of the rudder blade (2) on the other side of the thickening, said curvatures being adapted to the direction of rotation of the propeller (16).

11. Rudder (1 ) for an assembly according to one of the preceding claims, comprising a rudder blade (2), a rudder shank (5) which can be attached to the hull (6) of the ship, a rudder shaft (7) which runs through the rudder shank (5) and is rotatably mounted in the rudder shank (5) by means of bearings (3, 4), which rudder shaft (7) is attached to the rudder blade (2) at its bottom end, a trim blade (10) which is rotatably mounted on the rudder blade (2) and an operating mechanism (12-14) of the trim blade (10) which is coupled to the rudder shank (5), said rudder shank (5) extending into the interior of the rudder blade (2), characterized in that the rudder blade (2) has a thickening (15) which is situated between the top end and the bottom end of the rudder and which accommodates the operating mechanism (12- 14) of the trim blade (10).

12. Rudder (1) according to Claim 11, wherein the curvature of the rudder blade (2) on one side of the thickening (15) thereof is opposite to the curvature of the rudder blade (2) on the other side of the thickening.