GB1593607A

GB1593607A - Ship's rudder arrangement

Info

Publication number: GB1593607A
Application number: GB4150377A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-03-05
Filing date: 1977-10-05
Publication date: 1981-07-22
Also published as: ATA132678A; DE2709666A1; JPS53109390A; JPS6044197B2; AT365529B; DE2709666C2

Description

(54) A SHIP'S RUDDER ARRANGEMENT (71) I, WILLI BECKER of Danziger StraP 14-22 2000 Hamburg 1, Germany, a German Citizen do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly de scribed in and by the following statement: The present invention relates to a rudder arrangement on a ship, including a main rudder having at least one auxiliary rudder pivotably mounted thereon.

Arrangements for controlling the attitudes of the rudders to control ships and other watercraft are known. Such arrangements serve to position a single or multipart rudder against the incident water flow so that through the resulting angle of attack, between the water flow and the rudder, transversely directed forces are induced which control the direction of movement of the ship.

Multipart rudder arrangements are known which include gear having four links. However, such an arrangement has the disadvantage that during its operation its transmission ratios cannot readily be adapted, if they may be adapted at all, to the requirements of the widely differing functions needed for the rudder in use. As a result the drive for the rudder, the rudder shaft and connecting components must all be designed for a rated horsepower and speed for the ship and for the maximum of rudder angle anticipated. Thus, the design of the rudder is such that it has high performance characteristics for all its anticipated operating conditions, even in those cases where the high performance characteristics are neither necessary nor desirable.

According to the invention, there is provided a ship including a rudder arrangement, the rudder arrangement comprising a main rudder having an auxiliary rudder pivotably mounted thereon, a first drive located within the ship's hull for controlling the attitude of the main rudder, a second drive located within the ship's hull for controlling the attitude of the auxiliary rudder relative to the main rudder and a linkage interconnecting said second drive with the auxiliary rudder and enabling the attitude of the auxiliary rudder to be maintained at a selected angle to the main rudder, said linkage including a rectilinear sliding joint located outside both the hull of the ship and the main rudder.

So as to be able to use, for example, electrohydraulic linear converters or worm gears when using the second drive, a feature of the invention provides that the relative angle between the main and auxiliary rudder is adjustable between a zero value and maximum values.

Advantageously the first drive for the main rudder is connected thereto via a rudder shaft and the second drive for the auxiliary rudder is connected thereto via a drive shaft, and said linkage which comprises a lever one end of which is fixed to the lowermost end of the drive shaft and its other end rotatably carries a stub shaft freely extending into a slot in a guide arm fixed in a cantilevered manner to the auxiliary rudder.

An embodiment of the invention will now be described with reference to the accompanying drawings which show in: Figure 1 An arrangement according to the invention represented in a diagrammatic manner herein, Figure 2 A plan view of the arrangement of Figure 1 with the main and auxiliary rudders set for high speed ship operation, Figure 3 A plan view of the arrangement of Figure 1 with the main rudder set in line with the ship and the auxiliary rudder alone being used for controlling the ship's motion, Figure 4 A plan view of the arrangement of Figure 1 with the rudders set for low speed ship operation, Figure 5 A diagrammatic illustration of the five linkages of the arrangements of Figure 1.

Figure 1 shows a hull 10 which carries in a known manner, a main rudder blade 20 connected via a rudder shaft 24 to a drive or steering motor 25 located within the hull 10.

The main rudder 20 carries an auxiliary rudder 30 pivotably connected to its trail ing edge. The pivot axis of the auxiliary rudder 30 is indicated at 21. Auxiliary rudder 30 is connected to a second, individual, drive or steering motor 35 located within the hull 10.

The auxiliary rudder 30 is connected to motor 35 by a drive shaft 34, a lever 36 (one end of which is fixed to the lowermost end of the drive shaft 34), a stub shaft 39 rotatably mounted in the free end 36b of lever 36 and extending into a slot 38 formed in a guide member 37 carried by an arm 40 fixed in cantilevered manner to the auxiliary rudder 30. Stub shaft 39 is free to slide along the slot 38.

Figures 2 to 4 show details of the use of the rudder arrangement of Figure 1.

Figure 2 shows the arrangement with the rudders 20 and 30 set for use with high speed ship operation.

Another disposition of the rudders 20 and 30 for use in high speed ship operation is shown in Figure 3, in which rudder 20 is positioned with zero angle of attack and rudder 30 alone is used to control the ship's direction.

At low ship speeds the rudders 20 and 30 may assume the positions shown in Figure 4, in which large rudder angles, and large relative angles between the main and auxiliary rudders, and provided.

Figure 5 diagrammatically illustrates the rudder arrangement described herein which the main rudder blade is shown at 20, the auxiliary rudder at 30, the guide member is at 37, the arm is at 40 and the hull is at 10. Al, A2 and A3 represent slip or sliding joints and A4 and A5 represent swivel joints.

Control of the two drive or steering motors 25 and 35, for the rudder blade 20 and the auxiliary rudder blade 30 respectively, may be combined via a control mechanism 100, which may also be arranged to control the disposition of the rudders 20 and 30 in accordance with a preselected programme of operation.

It will be seen that the described rudder arrangements provide the following advantages over known rudder arrangements: 1) As the main rudder may be made smaller for the given rated ship speed without prejudicing the safety of the ship a smaller rudder shaft diameter may be used.

2) It is also possible to fit a smaller rudder drive or steering motor, particularly as - unlike the hitherto known rudders there is a restoring torque with the present arrangement so that the drive or steering motor is more efficiently used when the ship is travelling slowly.

3) The enabling of a smaller rudder which may operate with smaller rudder angles (or may make use of the auxiliary rudder alone) means that there is a smaller effective resistance to the ship's passage through the water and therefore a reduction in the ship's fuel consumption.

4) The control of the rudder arrangement is optimised as the drives to it are accessible from within the ship.

5) The high performance characteristic of a stabilizer rudder are also available when travelling slowly, without overloading the rudder drive motor or the rudder shaft.

6) Optimum rudder action is enabled by an advantageous, adaptable and economic construction of the various parts.

7) By balancing the various parts, and the use of rudder angles approximately 45" for the main rudder it is possible, by also making use of the auxiliary rudder, to partly deflect the propeller slipstream such that the propulsive force of the propeller is used to steer the vessel.

8) The arrangement may be fitted in existing existing vessels.

9) If one of the rudder drives fails in use, it is possible to use the other rudder drive alone and so permit the ship to continue its journey.

10) Commercially available linear or rotary rudder drives may be used.

11) All the rudder control functions are accessible from within the ship.

12) Conventional materials may be used for the manufacture of the rudder drives, bearings and components of the presently described arrangement.

13) Either or both of the rudder drives may be operated manually for special installations, e.g. when used in barges, tugs and the like.

14) As in use smaller forces occur, the service life of the arrangement is increased over that of the known arrangements.

15) The operation of the arrangement is more efficient due to the smaller loadings and the rudder drives may therefore be more effectively used at a better power factor.

WHAT I CLAIM IS: 1. A ship including a rudder arrangement, the rudder arrangement comprising a main rudder having an auxiliary rudder pivotably mounted thereon, a first drive located within the ship's hull for controlling the attitude of the main rudder, a second drive located within the ship's hull for controlling the attitude of the auxiliary rudder relative to the main rudder and a linkage interconnecting said second drive with the auxiliary rudder and enabling the attitude of the auxiliary rudder to be maintained at a selected angle to the main rudder said linkage including a rectilinear sliding joint located outside both the hull of the ship and the main rudder.

2. A ship according to Claim 1, wherein the relative angle between the main and

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ing edge. The pivot axis of the auxiliary rudder 30 is indicated at 21. Auxiliary rudder 30 is connected to a second, individual, drive or steering motor 35 located within the hull 10. The auxiliary rudder 30 is connected to motor 35 by a drive shaft 34, a lever 36 (one end of which is fixed to the lowermost end of the drive shaft 34), a stub shaft 39 rotatably mounted in the free end 36b of lever 36 and extending into a slot 38 formed in a guide member 37 carried by an arm 40 fixed in cantilevered manner to the auxiliary rudder 30. Stub shaft 39 is free to slide along the slot 38. Figures 2 to 4 show details of the use of the rudder arrangement of Figure 1. Figure 2 shows the arrangement with the rudders 20 and 30 set for use with high speed ship operation. Another disposition of the rudders 20 and 30 for use in high speed ship operation is shown in Figure 3, in which rudder 20 is positioned with zero angle of attack and rudder 30 alone is used to control the ship's direction. At low ship speeds the rudders 20 and 30 may assume the positions shown in Figure 4, in which large rudder angles, and large relative angles between the main and auxiliary rudders, and provided. Figure 5 diagrammatically illustrates the rudder arrangement described herein which the main rudder blade is shown at 20, the auxiliary rudder at 30, the guide member is at 37, the arm is at 40 and the hull is at 10. Al, A2 and A3 represent slip or sliding joints and A4 and A5 represent swivel joints. Control of the two drive or steering motors 25 and 35, for the rudder blade 20 and the auxiliary rudder blade 30 respectively, may be combined via a control mechanism 100, which may also be arranged to control the disposition of the rudders 20 and 30 in accordance with a preselected programme of operation. It will be seen that the described rudder arrangements provide the following advantages over known rudder arrangements:

1) As the main rudder may be made smaller for the given rated ship speed without prejudicing the safety of the ship a smaller rudder shaft diameter may be used.

5. A ship as claimed in claim 1 and substantially as herein described with reference to the accompanying drawings.

8) The arrangement may be fitted in existing existing vessels.

10) Commercially available linear or rotary rudder drives may be used.

11) All the rudder control functions are accessible from within the ship.

2. A ship according to Claim 1, wherein the relative angle between the main and

auxiliary rudder is adjustable between a zero value and maximum values.

3. A ship according to Claim 1 or Claim 2, wherein the first drive for the main rudder is connected thereto via a rudder shaft, and the second drive for the auxiliary rudder is connected thereto via a drive shaft, and said linkage which comprises a lever one end of which is fixed to the lowermost end of the drive shaft and whose other end rotatably carries a stub shaft extending into a slot in a guide arm fixed in cantilevered manner to the auxiliary rudder.

4. A ship according to any one of the preceding claims, wherein control of the first and second drives for the main and auxiliary rudders respectively is effected via a common control mechanism.