JP2010095239A - Rudder device for marine vessel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an increase in resistance because a propeller rear flow is abutted on a rudder from an oblique side, and to prevent an increase in resistance because the stream along a hull is also abutted on a skeg from an oblique side, in a rudder device for a one-shaft two-rudder vessel. <P>SOLUTION: In the rudders 6a, 6b and the skeg devices 7a, 7b of the one-shaft two-rudder vessel, in both left and right two rudders, an upper side area from the center line SC of a propeller shaft is made to a shape that twisting is provided toward a broadside that a propeller impeller ascends at advancement rotation, and a lower side area than the center line of the propeller shaft is constituted to a shape that twisting is provided toward a broadside that the propeller impeller descends at advancement rotation. Further, the skeg devices are constituted to a shape that twisting is provided toward an outer side respectively and are installed in symmetric to each other relative to the center line of the hull. Therefore, resistance generated by the rudder and the skeg device is reduced and the resistance of the hull is reduced to obtain the enhancement of propulsion performance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a marine steering.

FIG. 1 shows a side view of a stern section equipped with a conventional rudder and skeg. (FIG. 2) shows the II-II arrow view in (FIG. 1). Moreover, (FIG. 3) shows the III-III sectional arrow view in (FIG. 2), and (FIG. 4) has shown the IV-IV sectional arrow view in (FIG. 2). In general, a ship equipped with one propeller at the stern of the hull center is usually called a single-axle ship, and when a rudder is equipped immediately after one propeller, it is usually a single-axle-one rudder. It is called a ship. Most of the conventional single-shaft ships belong to this. Among them, there is a ship with two rudder installed immediately after the propeller in the single-shaft ship from the viewpoint of improving the maneuvering performance. In this specification, the case is referred to as a 1-axis 2-steering ship from the viewpoint of simplifying the description. As shown in FIGS. 1 and 2, the conventional single-shaft 2-rudder ship is provided with a rear end stern frame 2 of a hull 1, and a boshing 3 at a substantially central portion in the vertical direction thereof. The propeller shaft 5 is rotatably provided through the boshing 3, and the propeller 4 is provided at the rear end thereof. In addition, the front end of the propeller shaft 5 is connected to a main engine installed on the ship (not shown). Further, immediately after the propeller 4, two rudders 6 a and 6 b are provided for the hull center line CL so as to be within a circle of the rotation trajectory TIP at the tip of the propeller 4. In addition, two skegs 7a and 7b are provided on the upper side of each rudder 6a and rudder 6b, respectively, and a rudder member 8a penetrating vertically through the skate 7a and skeg 7b around the stern vertical line AP, and a rudder A head material 8b is provided, and the lower ends thereof are fixed to the upper ends of the rudder 6a and the rudder 6b, respectively, and the upper ends of the rudder material 8a and the rudder material 8b are respectively connected to a steering gear (not shown). Further, as shown in FIGS. 2 and 4, the rudder 6 a and the rudder 6 b are formed in a symmetrical cross-sectional shape in both the upper region and the lower region from the center line SC of the propeller shaft 5. Further, the skeg 7a and the skeg 7b are formed in a symmetric cross-sectional shape from the upper end to the lower end as shown in FIG. 2 and FIG. The figure shown in the conventional rudder device is intended for a case where the propeller 4 is configured to rotate clockwise as viewed from the rear to generate a forward thrust, and in this case, generally a clockwise propeller is used. In the present specification, it is also referred to as a clockwise propeller.

The two rudder 6a and rudder 6b in the so-called one-shaft two-ruder ship that has been put into practical use in the prior art are formed with a symmetrical cross-sectional shape in both the upper and lower regions from the center line SC of the propeller shaft 5. Since the skeg 7a and the skeg 7b are also formed in a shape having a symmetrical cross-sectional shape from the upper end to the lower end, when the hull 1 provided with the present apparatus is traveling forward, it is directed rearward along the hull 1. The flowing water flows from the outside toward the center of the hull. Therefore, the resistance generated from the skeg 7a and the skeg 7b is increased when the flow from the outside strikes the skeg 7a and the skeg 7b diagonally as shown in FIG. On the other hand, since a rotating flow in the same direction as the propeller is generated behind the propeller, the wake behind the propeller 4 is above the central ship SC of the propeller shaft 5 as shown in FIG. Since it flows from the port side toward the center of the hull and strikes the rudder 6a and the rudder 6b at an angle, the resistance generated by the two rudder increases, and further in the region below the center line SC of the propeller shaft 5 (see FIG. As shown in 5), since the wake of the propeller 4 flows from the starboard side toward the center of the hull, the resistance generated from the two rudders increases obliquely against the rudder 6a and the rudder 6b.

Problems to be solved by the invention

As described above, in a so-called single-shaft, two-rudder ship that has been put into practical use, the wake of the propeller hits the rudder from an angle and resistance increases, and the flow along the hull also hits the skeg from an angle. It has the problem that resistance increases.

Means to solve the problem

Therefore, the present invention not only reduces the inherent resistance generated from the rudder and skeg in the so-called one-shaft two-rudder ship, but also generates a force forward from the rudder and skeg to improve the reduction degree of the hull resistance. Proposed to improve propulsion performance, in order to provide a twist to the rudder in the direction of the wake of the propeller, in the region above the center of the propeller shaft, the propeller blades rise as the propeller blades move forward In the area below the center of the propeller shaft, a twist is formed toward the heel side where the propeller blade descends, and the skeg is turned outward. It is characterized by being formed in the provided shape.

Embodiments of the present invention will be described below with reference to the drawings. (FIG. 6) is a sectional view taken along the line III-III of (FIG. 2), (FIG. 7) is an explanatory view of the action, and (FIG. 8) is a sectional view taken along the line VIII-VIII of FIG. , (FIG. 9) respectively show sectional views taken along arrows IX-IX in (FIG. 2). This embodiment shows a case where a so-called propeller that generates thrust in the forward direction when the propeller rotates clockwise as viewed from the rear is clockwise. In the figure, the same reference numerals and symbols as those of the conventional ones are the same as those of the conventional ones, so that the description thereof is omitted. As shown in FIG. 6, the skeg 9 a and the skeg 9 b are wings that are provided with a twist from the vicinity of the rudder member 8 a and the rudder member 8 b toward the front side and have a convex shape on the inner side (near the hull center line CL). It is formed in a mold shape. As for the rudder 10a and rudder 10b, as shown in FIG. 8 above the center line SC of the propeller shaft 5, the starboard side rudder 10a and the starboard side rudder 10b are together with the rudder material 8a and rudder material. A twist is provided with the front side toward the port side from the vicinity of 8b, and the airfoil shape is formed in a convex shape on the starboard side. Further, in the area below the center line SC of the propeller shaft 5, as shown in FIG. 9, the starboard side rudder 10a and the portside rudder 10b are all directed toward the starboard side from the vicinity of the rudder member 8a and the rudder member 8b. The airfoil is provided with a twist, and the port side is formed in a wing shape with a convex shape. That is, the rudder 10a and the rudder 10b are configured in the same shape, but are asymmetrically installed with respect to the hull center line CL.

When the hull 1 in which the apparatus shown in the above embodiment is installed is traveling forward, the flow of water at the stern part is the same as that shown in FIG. Since both hit the front side, lift is generated toward the inside (near the hull center line CL), and the forward (hull direction) component of the lift acts as a thrust on the hull. (FIG. 7) shows an explanatory diagram of a vector for explaining this action. Generally, when a flow hits the front side of the airfoil, lift is generated toward the rear side, and the forward direction of the lift (the direction of travel of the hull) The component is the thrust. In addition, the lateral component of lift is lateral force, but if installed symmetrically with respect to the center of the hull, the lateral force is canceled out by both airfoils and becomes zero. On the other hand, the wake of the propeller 4 flows in the same rotational direction as the propeller 4 and therefore flows inward from the port side above the center line SC of the propeller shaft 5 and inward from the starboard side below. Accordingly, with respect to the rudder 10a and the rudder 10b having the wing shape, in the region above the center line SC of the propeller shaft 5, the starboard side rudder 10a and the starboard side rudder 10b are flowed to the front as shown in FIG. A lift is generated on the back side, and the forward component of the lift acts as a thrust to reduce the hull resistance. In addition, since it flows from the port side even below the center line SC of the propeller shaft 5, the flow of the starboard side rudder 10a and port side rudder 10b strikes the front surface and lift is generated on the rear side, and its forward component Acts as a thrust to reduce hull resistance. Therefore, the hull resistance at the time of navigation is reduced and the propulsion performance is improved compared to the conventional one.

The invention's effect

As described in detail above, the two skegs of the present invention in a so-called single-shaft, two-ruder ship are formed in a wing shape with a twist from the vicinity of the rudder to the front and outward and a convex shape inside. Installed on the object with respect to the center line of the hull, and in the upper area with the propeller shaft center as a boundary, a twist is provided from the vicinity of the rudder material toward the heel side where the propeller blade rises when the propeller rotates forward, and the propeller blade The lowering side is formed into a wing shape with a convex shape, while in the region below the propeller shaft center, a twist is provided from the vicinity of the rudder material toward the lower side where the propeller blade descends, and the vertical side where the propeller blade rises. By installing two rudders formed in a wing shape with a convex shape, thrust is generated from the above two skegs and rudder and acts to reduce hull resistance, and when two conventional skegs and rudder are installed Compared to a big advantage that the required horsepower said to be a reduction in the main engine when the hull hull resistance is reduced to sail at the same speed industrial, and to provide a very effective device.

These are the side views of the stern part of the conventional 1 axis | shaft 2 rudder ship. FIG. 2 is a view taken along the line II-II in FIG. (FIG. 2) is a sectional view taken along the line III-III in FIG. (FIG. 2) is a sectional view taken along the line IV-IV in FIG. (FIG. 2) is a sectional view taken along the line IV-IV in FIG. These are things of this invention (FIG. 2) by the III-III surface arrow. Is an explanatory view of the action. These are things of this invention (FIG. 2), and are VIII-VIII cross-sectional arrow views. These are things of this invention (FIG. 2) and are IX-IX cross-sectional arrow views.

Reference explanation

DESCRIPTION OF SYMBOLS 1 Hull 2 Stern frame 3 Boshing 4 Propeller 5 Propeller shaft 6a Rudder 6b Rudder 7a Skeg 7b Skeg 8a Rudder material 8b Rudder material AP Stern vertical line SC Propeller shaft center line CL Hull center line TIP Propeller blade tip trajectory 9a 9b Skeg 10a Rudder 10b Rudder

Claims (2)

In a so-called 1-axis 2-rudder ship where one propeller is provided at the stern part at the center of the hull and two rudders are provided behind it, the propeller rotates forward from the vicinity of the rudder material in the upper region with the propeller shaft as the boundary. Sometimes the propeller blades are twisted toward the wing side where the propeller blades rise, and the wing side where the propeller blades descend is formed in a wing shape with a convex shape. Two rudders are formed in the rotation trajectory at the tip of the propeller blades, with two rudders formed in a wing shape with a twist on the descending side and a convex shape on the side where the propeller wing rises. Rudder characterized by being installed at the same distance from the center line. In the so-called single-shaft, two-steer boat, a skeg provided in the gap between the upper ends of the two rudders and the hull. Two skegs that are installed symmetrically with respect to the center line of the hull.

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