KR20090110779A - Rudder with attached fin - Google Patents

Abstract

PURPOSE: A rudder with a pin is provided to improve propulsion efficiency and increase countercurrent gain by effectually controlling the water flow of the rear side of a screw propeller. CONSTITUTION: A rudder with a pin is positioned at the rear part of a screw propeller and changes the heading direction of a ship(1). A first pin(12) is formed at a rudder surface of a port side and a second pin(14) is formed at a rudder surface of right side in the rudder with a pin. In case of the right rotation of a screw propeller, one end of the first pin is mounted on the upper part than the center of the screw propeller and one end of the second pin is mounted on the lower part than the center of the screw propeller. In case of the left rotation of the screw propeller, one end of the first pin is mounted on the lower part than the center of the screw propeller and one end of the second pin is mounted on the upper part than the center of the screw propeller.

Description

Rudder with pins {RUDDER WITH ATTACHED FIN}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rudder equipped with a pin that is equipped with a ship and changes the heading direction of the ship.

Conventionally, in order to improve the propulsion performance, a structure in which the propeller rotational flow is changed into the flow in the propulsion direction, for example, the inclination angle (in response to the inflow angle that changes as the distance from the propeller shaft center to the lateral side from the axial center position of the rudder bulb) It is known that it is disclosed by the horizontal pin (Japanese Unexamined Patent Publication No. 6-305487) which set the twist angle. Further, in order to improve propulsion performance, it is known that a bulb is added to the rudder front edge near the propeller shaft center and a horizontal pin having the same right and left height integrated with the bulb (Japanese Patent Laid-Open No. 11-139395) is known. have.

However, the present inventors have analyzed in detail the flow field around the rudder at the rear where the propeller of the uniaxial right turn line operates, and as a result, water flow as shown in Fig. 12 occurs at the rudder plate front edge position. It was found that water flow as shown in FIG. 13 occurred at the rudder axis center position. That is, from FIG. 12 and FIG. 13, in the port side (right side in FIG. 12 and FIG. 13) of the rudder R, inside the rotation radius P of a screw propeller, it is higher than the center position C of a screw propeller. It turns out that the upward flow becomes strong from the side, and the downward flow becomes strong near the rudder (R). On the other hand, on the starboard side of the rudder (left in FIGS. 12 and 13), the downward flow is stronger inside the rotation radius of the screw propeller and below the center position of the screw propeller, and downward in the vicinity of the rudder R. It turns out that the flow of is getting stronger.

Therefore, in the rudder shaft center position of the propeller wake, as above-mentioned, in the left and right strings from which a propeller rotation direction differs, it flows above and below center position C, and the intensity | strength of a flow differs remarkably. For this reason, as described in Patent Document 1 and Patent Document 2, there is a problem that propulsion efficiency cannot be efficiently improved by propeller wake in a horizontal pin formed at the same height on both sides of the axis center position and the axis center position. .

12 and 13 which are the results of the flow field analysis at Reynolds number: 1080000 and the rotation speed of the screw propeller: 7.8 rpm are shown at the forward side, and the screw propeller (not shown) is stern at the forward direction. It is turning right when seen from the side. In the drawings, the direction of the arrow indicates the direction of flow in the plane, and the length of the arrow indicates the magnitude of the flow. In particular, the downward flow is stronger than the propeller center line on the rudder starboard side.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a pin capable of improving the propulsion performance (propulsion efficiency) by increasing the return gain by adjusting the flow of water behind the screw propeller more effectively. It is an object of the present invention to provide a mounted rudder and a ship having the same.

MEANS TO SOLVE THE PROBLEM This invention employ | adopted the following means in order to solve the said subject.

The 1st aspect of the rudder with which the pin which concerns on this invention was mounted is arrange | positioned at the back of a screw propeller, while changing the course direction of a ship, and the 1st pin is made to the rudder surface of a starboard side on the rudder surface of a port side. A rudder in which a second pin is formed one by one, respectively, wherein when the screw propeller rotates to the right when viewed from the stern side when moving forward, one end of the first pin is the rudder surface on the port side. The screw propeller is mounted above the center position of the screw propeller, one end of the second pin is mounted below the center position of the screw propeller on the rudder surface of the starboard side, and the screw propeller is moved forward. In the case of rotating leftward when viewed from the stern side, one end of the first pin is below the center position of the screw propeller on the rudder surface on the port side. While one end of the second pin is mounted above the center position of the screw propeller on the rudder surface on the starboard side, the other end of each pin is inward of the rotation radius of the screw propeller. In addition, it extends horizontally to a position where the upward or downward flow becomes strong.

The 2nd aspect of the rudder with a pin which concerns on this invention is arrange | positioned at the back of the screw propeller which rotates to a right turn when seen from the stern side at the time of forward movement, and changes the course direction of a ship, and the rudder surface of a port side The first pin is a rudder in which a second pin is formed on the rudder face on the starboard side, respectively, wherein one end of the first pin is the center of the screw propeller on the rudder face on the port side. It is mounted above a position, one end of the said 2nd pin is attached below the center position of the said screw propeller in the rudder surface of the said starboard side, and the other end of a 1st pin is smaller than the rotation radius of the said screw propeller. While extending upwardly inclined to the position where the upward flow becomes stronger, the other end of the second pin is further lower than the radius of rotation of the screw propeller. It extends horizontally to a position where the flow of incense becomes strong.

Moreover, when arrange | positioned behind the screw propeller which rotates to the left when viewed from the stern side at the time of advancement, the positional relationship of a 1st pin and a 2nd pin will be reversed left and right.

According to the rudder equipped with a pin according to the present invention, since the pin having a proper angle of incidence is generated for the flow of descending, rising and turning near the rudder, the propulsion horsepower can be reduced by reducing the hull resistance. Can be. In addition, it is possible to increase the propulsion horsepower reduction effect of the pin by moving the mounting position of the pin up and down as shown in FIG. 7 or by tilting the mounting angle as shown in FIG.

In addition, as shown in FIG. 13, in the upper port side of a rudder surface, it may become a flow close to the swirl flow which the upflow and inward flow combined, and in such a case, when the mounting angle of a pin faces the inclined upward direction, The effect of thrust generation by the pin can be made larger.

In the rudder in which the said pin is mounted, the rudder bulb which consists of an expanding body is formed in the front edge part which opposes the propeller boss of the said screw propeller, and the front edge is the said screw propeller wake. It is more preferable if it is twisted according to the inflow direction of.

According to the rudder equipped with such a pin, the rudder bulb causes the flow generated at the rear end of the propeller boss to flow along the surface of the rudder bulb, thereby weakening the boss vortex, thereby reducing the vortex resistance, thereby promoting propulsion performance (propulsion). Efficiency) can be further improved.

In addition, the front edge of the pinned rudder is twisted (twisted) in the up and down direction in accordance with the inflow direction of the screw propeller wake, and a gap occurs at the position of the rudder front edge propeller shaft height, causing cavitation. Although this gap is eliminated by the rudder bulb, the rudder cavitation generated at the front edge can be suppressed, and corrosion of the rudder surface and peeling of the paint from the rudder surface can be prevented.

The other end of the front edge is connected to the top of the rudder bulb, and one end of the front edge is connected to the bottom of the rudder bulb. That is, since the other end of the front edge and one end of the front edge are connected via the rudder bulb, the front edge can be easily processed, and the manufacturability can be improved.

In the rudder in which the pin is mounted, the first pin is formed to have an upward camber in a wing shape when viewed in a cross section, and the second pin has a downward camber in a wing shape when viewed in a cross section. It is more preferable if it is formed.

According to the rudder equipped with such a pin, the camber of the direction which raises lift is attached to each pin. The forward-facing component of this lifting force is the thrust for pushing the ship's hull in the forward direction, so that the thrust acts on the hull and the hull resistance is reduced.

Thereby, propulsion performance (propulsion efficiency) can be improved further.

According to the rudder equipped with the pin which concerns on this invention, since the pin which gave moderate angle to the flow which descends, rises, and turns in the vicinity of a rudder produces thrust, propulsion horsepower can be reduced by reducing hull resistance.

According to the rudder equipped with a pin according to the present invention, the pin having a proper angle of incidence with respect to the falling, rising and turning flow in the vicinity of the rudder generates thrust, thereby reducing the hull resistance and reducing the propulsion horsepower and improving the fuel economy. It has the effect that it can be planned.

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment of the rudder with a pin which concerns on this invention is described, referring FIGS.

1 is a right side view of a stern portion of a ship equipped with a rudder equipped with a pin according to the present embodiment as seen from the starboard side, and FIG. 2 is a port side side of a stern portion of a ship equipped with a rudder equipped with a pin according to the present embodiment. 3 is a front view of the rudder equipped with the pin according to the present embodiment as viewed from the bow side, and FIG. 4 is an experimental result obtained by sailing a ship equipped with the rudder equipped with the pin according to the present embodiment. A graph representing.

As shown in FIG. 1 or 2, the rudder 10 with which the pin which concerns on this embodiment was mounted is located at the stern bottom 4 of the stern part 3 located behind the screw propeller 2 (stern side). Is a plate member which is attached to the rudder shaft 5 extending vertically downward, and rotates in the vertical axial direction together with the rudder shaft 5 to change the course direction of the ship 1.

The screw propeller 2 is attached to the rear end (end of the stern side) of the propeller shaft 7 which penetrates the boss 6, and it is clockwise as seen from the stern side at the time of advancing with the propeller shaft 7 It rotates to the (right turn) and rotates counterclockwise (left turn) when seen from the stern side at the time of reverse travel.

By the way, the 1st pin 12 is the rudder surface 13 of the starboard side of the rudder 10 with a pin attached to the rudder surface 11 of the port side of the rudder 10 with which the pin was mounted concerning this embodiment. Each of the second pins 14 is formed (attached) therein.

As shown in FIG.2 and FIG.3, the 1st pin 12 has the one end (source) above the center position C of the screw propeller 2 from the edge part front edge side of the rudder surface 11 above. It is a small wing having an upward camber in a wing shape when viewed in cross section, which is mounted and extends in the horizontal direction (the port outward direction in FIG. 3). Moreover, the other end (tip) of the 1st pin 12 is inside the rotation radius P (refer FIG. 12 and FIG. 13) of the screw propeller 2, and to the position (region) in which an upward flow becomes strong. It is extended.

As shown in FIG. 1 and FIG. 3, the second pin 14 has one end (source) below the center position C of the screw propeller 2 on the front edge side of the central portion of the rudder surface 13. It is a small wing having a downward camber in a wing shape when viewed in cross section, which is mounted and extends in the horizontal direction (outer starboard direction in FIG. 3). In addition, the other end (front end) of the second pin 14 is located inside the rotation radius P (see FIGS. 12 and 13) of the screw propeller 2 and to a position (area) where the downward flow becomes strong. It is extended.

According to the rudder 10 with which the pin which concerns on this embodiment was mounted, the screw is further provided inside the rotation radius P of the screw propeller 2 which generate | occur | produces in the vicinity of the rudder surface 11 by the 1st pin 12. Screw propeller 2 generated near the rudder surface 13 by the second pin 14, while the upward flow generated above the central position C of the propeller 2 becomes weak (suppressed). Inward of the rotation radius P, the downward flow that occurs below the center position C of the screw propeller 2 is also weakened (suppressed).

Thus, the hull resistance can be reduced by rectifying the flow in the vertical direction near the rudder surface. In other words, the pin on the rudder surface can improve the propulsion performance (propulsion efficiency) by using the lift force generated in the flow in the vertical direction.

Fig. 4 is a graph showing an experimental result obtained by sailing a ship equipped with a rudder 10 equipped with a pin according to the present embodiment, the horizontal axis representing ship speed (kn: knot) and the vertical axis representing horsepower (kW). In addition, the broken line drawn from the lower left to the upper right in the figure is the data obtained from the ship which is not equipped with the rudder 10 equipped with the pin which concerns on this embodiment, and the solid line drawn from the lower left to the upper right in the figure. Is data obtained by the ship equipped with the rudder 10 equipped with the pin which concerns on this embodiment.

As shown in FIG. 4, in the ship equipped with the rudder 10 with a pin which concerns on this embodiment, the same ship speed as the ship which is not equipped with the rudder 10 with a pin which concerns on this embodiment is acquired. If the horsepower is at a minimum and the same horsepower as that of a ship not equipped with the rudder 10 equipped with the pin according to the present embodiment is provided, the ship speed increases (increases). Thereby, the fuel efficiency reducing effect of about 2% is obtained by the conventional ratio, and it is an experimental result effective as demonstrating the said effect by the pinwheel-mounted rudder 10 which concerns on this embodiment.

Moreover, according to the rudder 10 with which the pin was mounted which concerns on this embodiment, the pin 12 is attached so that the front edge may be located below the rear edge with respect to the corresponding rudder surface 11, and an upward camber is provided. The pin 14 is attached to the corresponding rudder face 13 so that its front edge is located above the rear edge, and a downward camber is attached. Lifting force can be generated toward the upper side and the lower side. And the forward-facing component of this lifting force becomes thrust which propels the hull of the ship 1 to a forward direction, and this thrust acts on a hull, and hull resistance is reduced.

Thereby, propulsion performance (propulsion efficiency) can be improved.

The rudder equipped with the pin which concerns on 2nd Embodiment of this invention is demonstrated, referring FIGS. 5-7. FIG. 5 is a right side view of the stern portion of the ship equipped with the rudder equipped with the pin according to the present embodiment, seen from the starboard side, and FIG. 6 is the port side of the stern portion of the ship equipped with the rudder equipped with the pin according to the present embodiment; It is a left side view seen from the side, and FIG. 7 is the front view which looked at the bow side with the rudder equipped with the pin which concerns on this embodiment.

As shown in Figs. 5 to 7, the rudder 20 equipped with the pin according to the present embodiment includes the rudder bulb 21, and as shown in Fig. 7, the front edge 22, 23) is different from the above-described first embodiment in that it is inclined with respect to the vertical axis (vertical axis). Other components are the same as those of the first embodiment described above, and therefore descriptions of these components are omitted here.

The rudder bulb 21 is provided with a propeller boss 2a (see FIG. 1 or FIG. 2) of the screw propeller 2 (see FIG. 1 or FIG. 2) at the front edge of the rudder 20 on which the pin is mounted. As the bulge body formed at the opposite position, as shown in FIG. 5 or FIG. 6, the diameter is sharply expanded over the front edge of the rudder 20 in which the pin is mounted at the bow-side cross section facing the propeller boss 2a. It is gently reduced from the front edge of the rudder 20 to which the pin is mounted toward the rear edge side. As shown in FIG. 5, the second pin 14 is formed below the rudder bulb 21 on the wake side from the front edge of the rudder 20 on which the pin is mounted. In addition, as shown in FIG. 6, the first fin 12 is formed above the rudder bulb 21 on the wake side from the front edge of the rudder 20. Thus, in consideration of the flow field near the rudder, the first fin 12 and the second fin 14 are formed in the vicinity of the rudder bulb 21 on the downstream side from the front edge of the rudder 20 on which the fin is mounted. By doing so, thrust can be obtained most effectively. In addition, as shown in FIG. 7, the cross-sectional shape of the rudder bulb 21 becomes substantially circular, and this cross section becomes the same shape also in any position from a bow side to a stern side.

Such rudder bulb 21 suppresses boss vortex generated at the rear end of the propeller boss 2a, that is, flows generated at the rear end of the propeller boss 2a along the surface of the rudder bulb 21. By flowing, the boss vortex is weakened (recovered) and the vortex resistance is reduced to improve propulsion performance (propulsion efficiency).

As shown in FIG. 7, the front edge 22 located above the rudder bulb 21, ie, above the rudder bulb 21, has one end (upper end) at the center position C of the screw propeller 2. ) Or the other end (lower end) is located on the port side than the center position (C) of the screw propeller (2), and at one end of the screw propeller (2) It is formed so that it may become substantially straight over the other end. The other end of the front edge 22 is connected to the top of the rudder bulb 21.

On the other hand, the front edge 23 located below the rudder bulb 21, that is, the lower side of the rudder bulb 21, has one end (upper side) at the starboard side than the center position C of the screw propeller 2. The other end (lower end) is the same as the center position (C) of the screw propeller (2) or is located at the port side than the center position (C) of the screw propeller (2), and is approximately straight from one end to the other end. It is formed to achieve. In addition, one end of the front edge 23 is connected to the bottom of the rudder bulb 21.

In other words, the leading edges 22, 23 are twisted (twisted) in accordance with the inflow direction of the screw propeller 2 wake, and thus the inflow direction from the screw propeller 2 with respect to the pinned rudder 20 ( Inlet angle) to suppress the rudder cavitation occurring at the front edges 22, 23 of the rudder 20 in which the pin is mounted.

According to the rudder 20 equipped with the pin which concerns on this embodiment, the flow which generate | occur | produces in the rear end of the propeller boss 2a by the rudder bulb 21 flows along the surface of the rudder bulb 21, and thereby boss vortex Since it becomes weak, eddy resistance can be reduced and propulsion performance (propulsion efficiency) can be further improved.

In addition, the front edges 22, 23 of the pin-mounted rudder 20 are twisted (twisted) in accordance with the inflow direction of the screw propeller 2 wake, thereby to the pin-mounted rudder 20. Since the inflow direction (inflow angle) of the screw propeller 2 downstream is reduced, the rudder cavitation occurring in the front edge 22, 23 can be suppressed, and the corrosion and the rudder surface 11 of the rudder surfaces 11 and 13 are prevented. , 13) can be prevented from peeling off the paint. In particular, high speed vessels such as container ships may cause corrosion and peeling of paint due to rudder cavitation. When the present invention is applied to high speed vessels such as container ships, the effect of suppressing rudder cavitation becomes remarkable.

The other end of the front edge 22 is connected to the top of the rudder bulb 21, and one end of the front edge 23 is connected to the bottom of the rudder bulb 21. Such a reaction rudder has a problem that, in the propeller shaft center portion, the warp direction is reversed, a step occurs in the front edge of the rudder, cavitation occurs in the step portion, and machining is difficult. However, in the present invention, since the other end of the front edge 22 and one end of the front edge 23 are connected via the rudder bulb 21, there is no case where a step at the rudder leading edge portion does not occur, so that The occurrence can be prevented, and the front edge can be easily processed, and the manufacturability can also be improved.

Since the other effect is the same as that of 1st Embodiment mentioned above, the description is abbreviate | omitted here.

The rudder equipped with the pin which concerns on 3rd Embodiment of this invention is demonstrated, referring FIG. 8 is a front view of the rudder equipped with the pins according to the present embodiment as seen from the bow side.

The rudder 30 with which the pin according to the present embodiment is mounted is different from the above-described first embodiment in that the first pin 31 is formed in place of the first pin 12. Other components are the same as those of the first embodiment described above, and therefore descriptions of these components are omitted here.

As shown in FIG. 8, the 1st pin 31 which concerns on this embodiment has the one end (source) from the center position C of the screw propeller 2 in the edge part front-end | tip side of the rudder surface 11 rather than the center position C of the screw propeller 2. It is a small wing | wing with a camber of an upward shape when seen from the cross section which mounts upward and extends in the inclined upper direction (direction of the upper right side in FIG. 8). Moreover, the other end (front end) of the 1st pin 31 is a position (region) which becomes stronger inside of the rotation radius P (refer FIG. 12 and FIG. 13) of the screw propeller 2, and an upward flow is strongest. Extends to.

As shown in FIG. 13, in the upper port side of a rudder surface, it may become a flow close to the swirl flow which the upflow and inward flow combined, and in such a case, like the 1st pin 31 which concerns on this embodiment, By making the mounting angle inclined upward, the effect of thrust generation by a pin can be made larger.

Since the other effect is the same as that of 1st Embodiment mentioned above, the description is abbreviate | omitted here.

The rudder equipped with the pin which concerns on 4th Embodiment of this invention is demonstrated, referring FIGS. 9-11. Fig. 9 is a right side view of the stern part of the ship equipped with the rudder equipped with the pin according to the present embodiment, seen from the starboard side, and Fig. 10 is the port side of the stern part of the ship equipped with the rudder equipped with the pin according to the present embodiment; It is a left side view seen from the side, and FIG. 11 is a front view which looked at the bow side with the rudder equipped with the pin which concerns on this embodiment.

The rudder 40 with which the pin which concerns on this embodiment is mounted differs from the above-mentioned 2nd Embodiment by the point that the 1st pin 41 is formed instead of the 1st pin 12. Since other components are the same as those of the second embodiment described above, the description of these components is omitted here.

As shown to FIG. 10 and FIG. 11, the 1st pin 41 which concerns on this embodiment has the center position (of the screw propeller 2) in the one end (source) from the top edge side of the top part of the rudder bulb 21. C) It is a small wing | wing with a camber of an upward shape when seen from the cross section which is mounted upward and extended in the inclined upper direction (direction of upper right side in FIG. 11). In addition, the other end (front end) of the first pin 41 is a position (region) where the flow of the upstream is stronger than the rotation radius P (see FIGS. 12 and 13) of the screw propeller 2. Extends to.

Since the operation and effect of the rudder 40 equipped with the pin which concerns on this embodiment is the same as that of 3rd embodiment mentioned above, the description is abbreviate | omitted here.

In addition, since the flow shown to FIG. 12 and FIG. 13 differs from ship to ship, it is preferable to perform a flow field analysis by ship, and to specify the area | region by which a 1st fin and a 2nd fin become effective. In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation can be implemented suitably and a change can be implemented as needed in the range which does not deviate from the technical idea of this invention.

In addition, the rudder equipped with the pin of the present invention is applied to general commercial ships such as ships, for example, gas carriers, tankers, container ships, ferries, RORO ships, car carriers, ores, bulk carriers, passenger ships, etc. Reduction and fuel economy can be improved and it can be expected as an energy saving ship.

BRIEF DESCRIPTION OF THE DRAWINGS It is a right side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 1st Embodiment of this invention from the starboard side.

It is a left side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 1st Embodiment of this invention from the port side.

Fig. 3 is a front view of the rudder equipped with the pins according to the first embodiment of the present invention as seen from the bow side.

4 is a graph showing experimental results obtained by sailing a ship equipped with a rudder equipped with a pin according to the first embodiment of the present invention.

It is a right side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 2nd Embodiment of this invention from the starboard side.

It is a left side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 2nd Embodiment of this invention from the port side.

It is the front view which looked at the bow side with the rudder equipped with the pin which concerns on 2nd Embodiment of this invention.

It is the front view which looked at the bow side with the rudder equipped with the pin which concerns on 3rd Embodiment of this invention.

It is a right side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 4th Embodiment of this invention from the starboard side.

It is a left side view which looked at the stern part of the ship equipped with the rudder with a pin which concerns on 4th Embodiment of this invention from the port side.

It is a front view which looked at the bow side with the rudder with which the pin which concerns on 4th Embodiment of this invention was attached.

Fig. 12 is a view of the flow of water at the front edge position of the keypad of a ship equipped with a conventional ship key from the bow side.

It is a figure which looked at the flow of the water in the key-axis center position of the ship equipped with the conventional ship key from the bow side.

<Explanation of symbols for main parts of drawing>

1: ship 2: screw propeller

3: stern part 4: stern bottom

5: rudder axis 6: boss

7: propeller shaft

10, 20, 30, 40: rudder with pins

11: rudder 12, 31, 41: first pin

13: rudder surface 14: second pin

21: rudder bulb 22, 23: front edge

Claims (5)

The rudder, which is arranged behind the screw propeller, changes the course direction of the ship, and is equipped with a pin having a first pin on the rudder surface on the port side and a second pin on the rudder surface on the starboard side, respectively. as, When the screw propeller rotates to the right when viewed from the stern side when moving forward, one end of the first pin is mounted above the center position of the screw propeller on the front edge side of the center of the rudder surface on the port side. One end of the second pin is mounted below the center position of the screw propeller at the center front edge side of the rudder surface on the starboard side, When the screw propeller is rotated to the left when viewed from the stern side when moving forward, one end of the first pin is mounted below the center position of the screw propeller at the center front edge side of the rudder surface on the port side. One end of the second pin is mounted above the center position of the screw propeller on the front edge side of the center of the rudder surface on the starboard side, The other end of each pin is a rudder equipped with a pin which extends horizontally inward of the rotation radius of the said screw propeller, and also to the position which the upstream or downward flow becomes strong. It is arranged in the rear of the screw propeller that rotates to the right when viewed from the stern side when moving forward, and changes the course direction of the ship, while the first pin is placed on the rudder side on the port side and the second rudder side on the starboard side. A rudder equipped with pins, each of which is formed with one pin, One end of the first pin is mounted above the center position of the screw propeller on the center front edge side of the rudder surface on the port side, and one end of the second pin is in front of the center portion of the rudder surface on the starboard side. On the edge side, it is mounted below the center position of the screw propeller, While the other end of the first pin extends inclined upward from the inside of the rotation radius of the screw propeller and to the position where the upward flow is strong, The other end of the 2nd pin is a rudder equipped with the pin which extends horizontally inward from the rotation radius of the said screw propeller, and also to the position which a downward flow becomes strong. The method according to claim 1 or 2, A rudder bulb formed of a bulge body is formed at the front edge portion of the screw propeller facing the propeller boss, and the front edge of the screw propeller is fitted with a pin that is twisted in accordance with the inflow direction of the wake of the screw propeller. . The method according to claim 1 or 2, A rudder equipped with a fin, wherein the first fin is formed to have an upward camber in a wing shape when viewed from a cross section, and the second fin is formed in a wing shape when viewed from a cross section and has a downward camber. The ship which comprises the rudder with which the pin of Claim 1 or 2 was mounted.

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