CN102625763A

CN102625763A - Rudder device

Info

Publication number: CN102625763A
Application number: CN2010800432306A
Authority: CN
Inventors: J-O·福斯特罗姆
Original assignee: Rolls Royce AB
Current assignee: Kongsberg Maritime Sweden AB
Priority date: 2009-08-27
Filing date: 2010-08-23
Publication date: 2012-08-01
Also published as: WO2011025444A1; KR20120046324A; WO2011025444A9; EP2470421A1

Abstract

This invention relates to a rudder device (1) for a sea-going vessel, comprising a first larger rudder portion (2) pivotally mounted around a first axis (4), and a second smaller rudder portion (3) pivotally mounted about a second axis (5) that extends substantially parallel to the first axis (4), wherein said second axis (5) is positioned in front of said first axis (4).

Description

Rudder gear

Technical field

The rudder gear that is used for the oceangoing voyage ship has the rudder gear that comprises two rudder portions.

Background technology

In maritime affairs industry, that the corrosion phenomenon on the seagoing vessel rudder that is caused by cavitation erosion particularly mainly moves in seawater is large-scale, be a well-known problem in the field of high speed vessel.In the use of the rudder of the high speed seagoing vessel of the screw propeller that is provided with high capacity, the cavitation erosion of generation often causes the infringement of rudder, and more specifically, has caused the infringement towards the leading edge of the rudder of the bow of ship.

In patent DE202004021223, disclosed a kind of rudder, it has the blade part of two stacks, and one is positioned at top and one and is positioned at the bottom, and this rudder is provided with two shape of cross sections thus.Above-mentioned rudder structure is designed to reduce cavitation erosion, but this minimizing mode is not enough to effectively provide significant an improvement.Do not avoid corrosion phenomenon through this structure yet.

Therefore significant need is applied to cavitation erosion and the improved method of etching extent on the rudder gear of oceangoing voyage ship in order to minimizing.

Summary of the invention

The objective of the invention is to address the above problem or reduce to minimum to major general's the problems referred to above.This purpose realizes through the rudder gear according to claim 1.

Because described device, near the propeller race that the first rudder portion avoids producing any screw propeller that water body that the oceangoing voyage ship passes and ship use have a strong impact on.Thus, the corrosion phenomenon in the first rudder portion will become avoid easily and certain degree prevented cavitation erosion.

In addition; This structure will make the first rudder portion and the second rudder portion can be around they rotational separately; Make two parts be oriented relative to one another to an angle; The advantage of its generation is: the shape that the angle of attack of the propeller race in the second rudder portion and the first and second rudder portions form together will improve the lift of rudder gear considerably, reduce the cavitation erosion that rudder gear suffers simultaneously and measure.This makes can use littler and/or lighter rudder gear, and still can obtain and bigger rudder gear identical functions and effect.Can also use the rudder gear of the normal size of the ship that is used for being discussed, realize that thus higher levels of ship handles control.

The possible deflection of the second rudder portion is no more than 35 ° usually, preferably is no more than 20 °, and more preferably in ± 5-15 ° scope.

Preferably, the axis of the axis of the first rudder portion and the second rudder portion can rotate in a synchronous manner.Perhaps, rudder portion can reach independently of one another individually and move.

According to an aspect of the present invention, the distance between the first rudder portion and the second rudder portion can change, as the placement of the axis separately of two parts can change.Preferably, control rudder gear of the present invention operate machine be dimensioned to all modification with remodeling compatible.Preferably, the second rudder portion will be preferably 10-20% less than 25% of total chord length of rudder gear.

According to another aspect of the present invention, the first rudder portion and the second rudder portion can control and in hull, operate through independent maneuvering system individually.Can provide mechanical gear that two parts are connected.The second rudder portion can preferably programme and automatic guidance by this way, promptly based on the angle of the first rudder portion or individually or combine one or more other parameters, confirms moving of the second rudder portion like the speed of ship and/or the speed of screw propeller etc.Preferably, the second rudder portion can not manual manipulation in operation mode, but can programme with the various situation of automatic coupling.

According to another aspect of the invention, the first rudder portion and the second rudder portion will control through the electronic or HM Hydraulic Motor that is arranged on the first rudder portion and second rudder portion place respectively individually.

Description of drawings

To describe the present invention in detail with reference to accompanying drawing now, wherein:

Fig. 1 shows the lateral plan of rudder gear according to a preferred embodiment of the invention,

Fig. 2 shows along the viewgraph of cross-section of seeing from the top of the rudder gear of the II-II line intercepting of Fig. 1,

Fig. 3 shows and is in the viewgraph of cross-section of seeing from the top to the rudder gear of Fig. 2 of the maximum deflection position that a lateral deviation is changeed,

Fig. 4 shows and is in the viewgraph of cross-section of seeing from the top to the rudder gear of Fig. 2 of the maximum deflection position of opposite side deflection,

Fig. 5 shows the perspective side elevation view according to another embodiment of rudder gear of the present invention,

Fig. 6 is the transparent view along the VI-VI line intercepting among Fig. 5.

Fig. 7 shows the transparent view of rudder gear according to another embodiment of the present invention,

Fig. 8 shows the perspective side elevation view according to the embodiment of rudder gear of the present invention, and this rudder gear has the spherical shell (bulb) that connects with the propeller boss that has end cap.

Fig. 9 shows according to the transparent view of an embodiment more of the present invention, and

The view of Figure 10 for seeing from the top of embodiment shown in Figure 9.

Figure 11-14 shows according to the different views of an embodiment more of the present invention, and

Figure 15-18 shows according to the different views of an EXAMPLE Example more of the present invention.

The specific embodiment

Among Fig. 1, can see the lateral plan of rudder gear 1 according to a preferred embodiment of the invention.Rudder gear 1 is the form of flat rudder (spade rudder), and comprises rudder portion 2, can be attached to the hull 6 of ship (for example ship) around the rudder portion 2 that first axle 4 pivots through minor axis 40.The position apart X of second axis 5 and first axle 4, the second rudder portion 3 is provided with around second axis 5 pivotally.

Axis

4 and 5 is parallel basically.The length of the second rudder portion 3 is preferably less than 25% of chord length B, and is preferred in the interval of 10-20%.

Fig. 2 shows along the cross sectional drawing of the rudder gear 1 of Fig. 1 of II-II line intercepting, wherein can find out the relation between the first rudder portion 2 and the second rudder portion 3.In the inside 20 of the first rudder portion 2, show first axle 4 with said minor axis 40 with aliging.The leading edge 23 of the first rudder portion 2 is pointed to the direction of the bow of ship, and trailing edge 24 points to the direction of stern.The starboard surface 21 of rudder portion 2 is pointed to starboard and larboard direction respectively with larboard surface 22.

The second rudder portion 3 is positioned at the direction of the bow of ship with respect to the first rudder portion 2, make the trailing edge 32 of the second rudder portion 3 be positioned over the first rudder portion 2 leading edge 23 near.Inside 30, the second rudder portions 3 that second axis of rotation 5 extends through the second rudder portion 3 also are connected to hull through minor axis 50.The second rudder portion 3 also comprises leading edge 31, starboard surface 34 and the larboard surface 33 of the bow that points to ship.Trailing edge 32 has the shape with the opposite shape of the leading edge 23 of the first rudder portion 2; Make trailing edge 32 can be arranged at least in part around leading edge 23; And terminate in the relatively bight 35,36 of point,

bight

35,36 has formed the border between trailing edge 32 and starboard side surface 34 and the port side surface 33 respectively.Bight 35,36 can be formed for the device that moves of the first rudder portion 2 that limits, and perhaps can be processed by elastomeric material, or be positioned in the risk that maximum deflection place does not contact with the first rudder portion.

The first rudder portion 2 and the second rudder portion 3 relative to each other are provided with by this way like this, make the second rudder portion, 3 parts surround the first rudder portion 2, and leading edge 23 is protected by trailing edge 32 on the ship's head of ship.

First axle 4 can be placed on diverse location along chord length, and therefore can regulate and move the needed power of rudder.Usually useful is, locatees first axle 4 to the stern direction apart from 1/3 ± 10% of the length of leading edge 23 about rudder portions 2.Second axis 5 can be positioned closer to the middle part of the second rudder portion 3.Two

minor axises

40,50 are controllably located/are moved to allow moving of expectation to move/location through any suitable mechanism/means (not shown).

Fig. 3 shows two the

rudder portions

2,3 that are in the maximum deflection position that deflects to a side together.The first rudder portion 2 rotates so that its trailing edge 24 deflects to port side around its axis 4 now, and its leading edge 23 deflects to starboard side simultaneously.On the other hand, the deflection on the contrary of the second rudder portion 3 is so that its trailing edge 32 astarboard lateral deviations are changeed its leading edge 31 lateral deviation commentaries on classics aport simultaneously.This result who controls is, attached the mobile of ship on it of

rudder portion

2,3 is changed, and makes ship port topside.Because the design of rudder portion, increase from the effect application force aboard ship of rudder, thereby can obtain to be used to bigger power that ship is turned to.

Shown in the position, rudder portion is turned to their maximum deflection position towards a side, makes the bight 36 of the second rudder portion 3 move more near first axle 4, and the front portion on larboard surface 22 moves more near starboard side, and is a kind of L shaped with common formation.Can be created in stronger propeller race and the influence of ambient water behind the screw propeller of ship when therefore, leading edge 23 is not received ship to move through water by protection.These current possibly cause cavitation erosion on the other hand in the front portion of the first rudder portion 2, but can be weakened by substantial through these influences of design of novelty.In addition, because the second rudder portion 3 points to different directions, current will lead with the mode that reduces the whole resistance to water-flow on the rudder gear 1 around two

parts

2,3 of being regarded as one unit.Can lead the position of rudder portion 3 to obtain the lowest possible angle of attack that water gets into rudder.To the performance of rudder gear 1 useful be that bight 36 stopped before the actual contact first rudder portion when moving in the second rudder portion 3.

Because the effect through this structure rudder kick is greater than the situation through conventional rudder deflection, so

rudder portion

2,3 itself can make forr a short time and lighter, but with regard to the control ship, still produced identical application force.On the contrary, the size of the ship that is generally used for specific dimensions can be processed by

rudder portion

2,3, but has produced bigger application force and to the stronger control of ship, this will be useful in certain embodiments.

The rudder skew opposite with Fig. 3 has been shown among Fig. 4, and wherein the leading edge 23 of the first rudder portion 2 is pointed to port side, and the leading edge 31 of the second rudder portion 3 is pointed to starboard side simultaneously.Now, another bight 35 is more near the first rudder portion 2, and leading edge 23 is thus by the second rudder portion 3 " protection ".The result that rudder gear 1 is in this position realizes ship topside rotation to the right.

Rudder portion can be controlled such as the independent motor of electricity or HM Hydraulic Motor and rotated (not shown) independently of one another, perhaps can connect through the mechanical attachment that is fit to kind so that the second rudder portion 3 is driven in the first rudder portion 2 or opposite.Like this, single-motor and simple relatively control system just are enough to be used in two

rudder portions

2,3 of rotating rudder device 1.Rudder gear 1 can also be by more complicated control circuit control, and this control circuit programming is to adapt to each

rudder portion

2,3 moving to realize the maximum efficiency of each deflection with respect to another.A beneficial method of control rudder gear 1 is: for control unit is programmed to mate the deflection of the first rudder portion 2 through the angle that makes the second rudder portion 3 move predetermined quantity.This program can be modified sometimes, to allow mating different situations through the different deflection of the second rudder portion 3, realizes the high-caliber control to rudder gear 1 operation thus.

Like Fig. 2-shown in Figure 4; According to being preferably designed for like this of this embodiment, promptly moving of

rudder portion

2,3 limited by their mutual action, makes second portion 3 only can in limited range of deflection, move around its

axis

4,5; For example+30 °, be preferably+20 ° to-20 ° to-30 °.

Fig. 5 and Fig. 6 show according to another embodiment of the present invention, wherein only use a pivot minor axis 40 that

rudder gear

2,3 is attached to the hull 6 of ship, this 40 also formed the first rudder portion 2 that is used for first pivot axis 4.Cross sectional drawing from Fig. 6 can be found out; The second rudder portion 3 is connected to the first rudder portion 2 through

lever arm

35,56; And the position at pivot axis 5 is attached to second rudder 2 pivotally, and this pivot axis 5 coaxially extends in first pivot axis 4 in the main body of the first rudder portion 2 and contiguous its leading edge in the inside 25 of the hollow of the first rudder portion 2.First lever arm 56 is attached to axle 40 regularly and vertically stretches out from axle 40, and this first lever arm 56 is connected to the end of second lever arm 35 pivotally.Through rotation primary shaft 40, the pivot that pivotal arm 56 will be arranged for lever arm 35 moves, and it will cause the second rudder portion 3 to move in opposite direction around its pivot axis 5 conversely.

Fig. 7 shows the perspective schematic view according to another embodiment of rudder gear 1 of the present invention.This rudder provides a kind of design at this; Wherein the first rudder portion 2 and the second rudder portion 3 are connected (not shown) and connect through being combined in hinge in the second rudder portion 3, make be used to the to

pivot axis

4,5 of the first rudder portion 2 and the second rudder portion 3 coaxial and extend in the second rudder portion 3.Here, the second rudder portion 3 is mounted to axle 50, and this 50 extends in the hull 6 of ship (not shown) through suitable attachment arrangement.The coaxial axle 50 that is provided with in above-mentioned axle 50, it also extends through hull to be used for the first rudder portion 2.Two axles can pivot independently.Therefore, this scheme drawing has presented an attachment point that is attached to hull and can be enough to control independently two rudder portions 2,3.Through suitable driving device (not shown); " follower " can be used to make the direction deflection in the opposite direction of the first rudder portion, 2 edges and 3 deflections of the second rudder portion, therefore can realize the moving of expectation of

rudder portion

2,3 and need not to be used for the independent control system of the first rudder portion 2.

The perspective side elevation view that is provided with the rudder gear 1 of spherical shell (bulb) 25,37,90 according to of the present invention has been shown among Fig. 8.Two

rudder portions

2,3 are depicted as and are arranged on screw propeller 7 rears, and prop shaft 8 provides power for screw propeller 7.In order to optimize flow condition, the spherical shell device that provides becomes to comprise three parts.Rise from behind, at first be positioned at size that the spherical shell 25 in the bigger rudder portion 2 has along continuously reducing from the direction of leading edge 23 to trailing edge 24.The position that spherical shell 25 has is coaxial basically with respect to the axis of prop shaft 8.The second rudder portion 3 also is provided with spherical shell portion 37, spherical shell portion 25 in-lines of this spherical shell portion 37 and bigger rudder portion 2.In addition, middle spherical shell portion 90 is arranged between the leading edge of the end of screw propeller/hub (hub) 7 and the second rudder portion 3.The 3rd spherical shell portion 90 is attached to tubular bracket 9, and this tubular bracket 9 is attached to the hull (not shown), and the 3rd spherical shell portion 90 provides the passage 91 that is used for cable and/or hydraulic pipe etc.In addition, tubular bracket 9 can be used to the pivot axis 5 of the second rudder portion 3 that is provided for (and the possible first rudder portion 2 that is used for) and possible (not shown) such as driving device.Tubular bracket 9 can also be provided with movably, with

movable part

2,3 mutual actions of rudder gear 1.Yet the locomotivity of tubular bracket 9 can not need as other part big, for example preferably is only approximately ± 5 °.If use the screw propeller 7 with variable-pitch, tubular bracket 9 can connect through the rotation in the rear end that is arranged on the propeller boss (not shown) so provides hydraulic pressure and/or cable to propeller boss.Obviously, the above-mentioned principle that has such central support 9 can not have spherical shell ground to use yet.

In addition, Fig. 8 shows and can be divided into bottom 31 and top 32 so that the second rudder portion 3 of other function to be provided.Through by this way separately and each

part

31,32 itself controlled, can obtain additional advantage.A benefit is that

part

31,32 can make and realize more favourable flow pattern (less resistance) when (at least basically) keeps straight on forward when promoting ship along the less relatively angle of a deflection in each direction (for example 3-10 °) with the turbulent flow of compensation from screw propeller like this.Predetermined inflection point (for example 5 °) in the first rudder portion 2 is located, and the

part

31,32 of the second rudder portion 3 is same moved further as above Fig. 1-4 is described once more.

Fig. 9 and 10 shows another embodiment according to the embodiment of the invention with transparent view.Here the first rudder portion 2 is divided into main 2A of portion and rear portion 2B.The first rudder portion 2 is attached to hull rotatably through axle 40, and axle 40 is attached to the 2A of main rudder portion conversely regularly.Coaxially being arranged on minor axis 40 for second 50 can pivot around minor axis 40 outward and therefore.It is coaxial that the second rudder portion 3 is attached to second 50 and its pivot axis and second 50 regularly.Therefore, the first rudder portion 3 position that can be independent of minor axis 40 and the 2B of main rudder portion is moved and is located.In addition, the lever arm 57 that extends back is attached to second 50.Have in the lever arm 50 and pin 203 mutual action longitudinal openings 58.Pin 203 fixedly is attached to second lever arm 202, and this second lever arm 202 is attached to the axle 201 that is fixed to the back rudder 2B of portion.In addition, axle 201 pivots is arranged on (not shown) in the hinge means, and hinge means is attached to the 2A of main rudder portion regularly.Therefore, when lever arm 57 pivots via axle 50, pin 203 will radially move, and also make second lever arm 202 move the back rudder 2B of portion thus.Therefore, through the position that is positioned at expectation with second 50, the second rudder portion 3 will move/locate with the back rudder 2B of portion and form rudder, and this rudder has the ability of enhancing to produce the guidance force and the risk that do not cavitate.

Figure 11-14 shows the another embodiment that has realized desired function according to of the present invention.In this embodiment, the second rudder portion 3 is attached to panel assembly 200 regularly, and this panel assembly 200 extends to the stern direction from the top of the second rudder portion 3, makes the rudder portion 2 that wins be positioned to be located immediately at panel assembly 200 belows.Figure 11 and 12

centered rudder portions

2,3 are depicted as and are in non-inflection point, and Figure 13, shown in 14 for being in inflection point.Figure 11 and 13 is that Figure 12 and 14 is plan views of seeing from the top from the transparent view of top stravismus.Roughly be provided with the notch 230 of curved at the middle part of panel assembly 200, the control lever shaft 40 with central axis 4 stretches in this socket 230, and central axis 4 is fixing with respect to hull 6.The notch 230 of curved extends in the panel assembly 200 along horizontal direction.The width of notch 230 corresponds essentially to the diameter of control lever shaft 400.The lateral length of notch 230 is about 2-3 a times of control lever shaft 40 diameters.Be provided with groove 240 with respect to notch 230 to the stern direction, it is substantially rectangle and its long edge longitudinal extension, promptly is in the direction that non-inflection point rudder the extends bearing of trend of notch 300 (promptly perpendicular to).Be provided with sliding panel 110 in the groove 240, roughly less than the longitudinal extension part of groove 240, its width corresponds essentially to the width of groove 240 to the extension of this sliding panel 110.Therefore, sliding panel 110 can slide in groove 240 along the longitudinal direction.Sliding panel 110 is attached to the minor axis 50 that extends upwardly in the hull 6 rotatably.Plate 110 is arranged on the minor axis 50 pivotally, and this minor axis 50 has formed the rotation axis 5 that is used for second rudder 3.

The first rudder portion 2 is attached to panel assembly 200 in its front portion through minor axis 400 pivotally, and wherein this minor axis 400 upwards stretches out in the top side of the first rudder portion 2.Minor axis 400 stretches in the hole 210 of ring device 220, and this ring device 220 stretches out to stern from the stern-side of the second rudder portion 3.Therefore ring device 220 fixedly is attached to the rear side of the second rudder portion 3.Provide similar device in the bottom of the second rudder portion 3, to be provided for the making first rudder portion, 2 hinges be attached to the second rudder portion 3.

The function of embodiment shown in Figure 11-14 is following.The position of control lever shaft 40 is the position that angle has been confirmed the first and second rudder portions 2,3.Control lever shaft 40 is located such that

rudder portion

2,3 is in line each other, does not promptly realize deflection among Figure 12.When control lever shaft 40 deasil rotates,, therefore also will rotate the first rudder portion 2 because control lever shaft 40 is attached to the first rudder portion 2 regularly.The result is that minor axis 400 will apply pressure on the ring device 220, and ring device 220 is along promoting the second rudder portion 3 in the direction of the clock.The result is panel assembly 200 cw moves through pivoting around second axis 5, and makes sliding panel 240 can slide mobile at groove 230 simultaneously.Control lever shaft 40 can continue deflection and move, up to the end 36 of control lever shaft 40 contact notches 300.It should be noted that in the deflection that the distance between distance between the center 4 of second axis 5 and control lever shaft 400 and central axis 4 and the minor axis 400 is constant, and first axle 5 will move near minor axis 40.

Figure 15-18 shows the another embodiment that realizes function of the present invention.Among this embodiment, control lever shaft 40 also is used as the pivot axis 4 of the first rudder portion 2.Therefore, the second rudder portion directly follows the rotation of control lever shaft.Similar with shown in Figure 11-14, the second rudder portion 3 is connected to the front portion of the first rudder portion 2, wherein this minor axis and the ring device mutual action that is attached at the rear end of the second rudder portion 3 through the minor axis hinge at the front area of the first rudder portion 2.The result is that the second rudder portion 3 will follow moving of the first rudder portion 2, and promptly ring device has the fixing center with respect to the minor axis of the first rudder portion 2.In order the second rudder portion 3 to be set around minor axis deflection; Be provided with hydraulic pressure (and/or electronic and/or pneumatic) push-pull mechanism 7, it can be positioned at inflection point with the second rudder portion 3 by means of the pin 740 that acts in the groove structure 360 with respect to the first rudder portion 2 via lever apparatus.Push-pull mechanism 7 comprises first hydraulic actuating cylinder 710 and second hydraulic actuating cylinder 720 of the every side that is positioned at the first rudder portion 2, and their rear end is attached to the second rudder portion regularly through base support 730.The front end of hydraulic actuating cylinder 710,720 is attached to the inflector assembly 770 with respect to 2 horizontal expansions of the second rudder portion.Base support 730 is attached to upper sleeve 750 regularly, and inflector assembly 770 is attached to lower sleeve portion 760.Upper sleeve is fixing with respect to control lever shaft 400, and lower sleeve portion 760 extends downward the inside of the first rudder portion 2 from the hull top.Lever apparatus (above mentioned) is attached to lower sleeve portion 760, make when sleeve 760 rotations it will move in the groove 360 pin 740 so that the second rudder portion 3 rotate around second axis 5.Control lever shaft 400 cw deflection fully has been shown among Figure 18, has made the rudder portion that wins be positioned to become bigger angle [alpha] with respect to the longitudinal direction of ship.In addition, first hydraulic piston 710 is drawn into while second piston 720 and is pushed out, and causes inflector assembly 770 to pivot with respect to control lever shaft 400 conter clockwises, and it makes the 3 corresponding deflections of rudder portion to be positioned to becoming less acute angles beta with respect to longitudinal direction conversely.Must be noted that; With comparing shown in Figure 11-14; Wherein mechanism is for being that the specific rotation of the special angle of control lever shaft 400 will make the first rudder portion 2 and the second rudder portion 3 both are positioned at preposition like this; And according to this embodiment, no matter no matter the position of the second rudder portion 3 can be controlled and the position of control lever shaft 40, promptly the position of the first rudder portion 2 independently.

One of ordinary skill in the art will readily recognize that the scope that all possibly be positioned at appended claim to a lot of modification of the present invention.For example the present invention can be used for dissimilar rudder designs.In addition, the invention is not restricted to rudder together with use, but its principle also can provide quite similar advantage in other are used, for example pillar, stabiliser and/or the bracing strut of the pillar of POD screw propeller (stay), rotatable propeller.In brief, it can relate to all different types of devices of the aerofoil profile with some aerofoil profiles that move in the approximate water and variable-angle is provided in current.

In addition, can predict, some in the different aspect of more than describing, for example the principle of the use shown in Figure 11-14 and/or Figure 15-18 and middle rotating mechanism can be used as independent patent application theme.

Claims

1. rudder gear (1) that is used for the oceangoing voyage ship; Comprise the first bigger rudder portion (2) of installing pivotally around first axle (4); With the second less rudder portion (3) of installing pivotally around second axis (5); Second axis (5) is roughly parallel to first axle (4) and extends, and it is characterized in that said second axis (5) is positioned at said first axle (4) before.

2. according to the rudder gear (1) of claim 1, wherein, at least one in the said axis (4,5) belongs to the axle in the hull structure (6) that is installed in the oceangoing voyage ship.

3. according to the rudder gear (1) of claim 1 or 2, wherein, comprise the device (35,36) that the rotation that is used to the first rudder portion (2) that limits is moved.

4. according to each rudder gear (1) among the claim 1-3, wherein, the length of the second rudder portion (3) is less than 25% of the length of rudder gear (1), preferably in the interval of 10%-15%.

5. according to each rudder gear (1) among the claim 1-4, wherein, the second rudder portion (3) is arranged to cover at least in part the leading edge (23) of the first rudder portion (2).

6. according to each rudder gear (1) in the above claim, wherein, the rear wall of the second rudder portion (3) is configured as the shape that adapts to said leading edge (23).

7. according to each rudder gear (1) in the above claim, wherein, first axle (4) is installed by this way, i.e. the first rudder portion (2) less than 1/2 length, preferably be placed on axis (4) side towards the bow of oceangoing voyage ship less than 1/3 length.

8. according to each rudder gear (1) in the above claim, wherein, the first and second rudder portions (2,3) rotate along opposite direction in the operating period of rudder gear (1) each other.

9. according to Claim 8 rudder gear (1), wherein, the first and second rudder portions (2,3) move independently of each other.

10. according to Claim 8 rudder gear (1), wherein, the rudder portion (3,2) in the rudder portion is driven in another rudder portion (2,3).

11. according to each rudder gear (1) in the above claim, wherein, the first and second rudder portions (2,3) are that they do not have the physics contact each other by control by this way.

12. according to each rudder gear (1) in the above claim, wherein, at least one in the rudder portion (2,3) rotated through the rotation of axle (40,400) mounted thereto.

13. according to each rudder gear (1) in the above claim, wherein control system is set for the control second rudder portion (3) moving with respect to the first rudder portion (1).

14. according to each rudder gear (1) in the above claim; Wherein, Mobile being limited of the second rudder portion (3), the angle that the second rudder portion (3) that makes can be from the leading edge (31) of the second rudder portion (3) towards the rotated position of the bow of ship less than 30 °, preferably less than 20 °, more preferably less than 5 °.

15. according to each rudder gear (1) in the above claim, wherein, the first and second rudder portions (2 ', 3 ') link through linkage.

16. according to the rudder gear (1) of claim 15, wherein, said mechanism controls rudder portion (2,3) moves, and makes them rotate along opposite directions.

17. according to each rudder gear (1) in the above claim, wherein, the second rudder portion (3) is divided into top (31 ') and the bottom (32 ') that can move independently of one another.

18. according to each rudder gear (1) in the above claim, wherein, the mounting bracket of rudder gear (1) and/or said rudder gear (1) is combined with the screw propeller or the spherical shell of oceangoing voyage ship.