JP2004136779A - Course stabilizing device for ship - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a course stabilizing device for a ship equipped with an appendage at the rear end of the skeg in stern to facilitate the generation of an eddy from the rear end of the skeg during navigation, thereby improving the course stability of the ship. <P>SOLUTION: A plate-like member 3, which extends symmetrically and horizontally into water from the bottom edge part of the rear end of the skeg 2 provided projectingly along the center line of the hull 1, is provided in the lower part of the bottom of the stern of a hull 1. During navigation, the eddy is generated at the rear end of the skeg 2 (near the connecting section with the plate-like member 3 in particular) or at both the ends of the plate-like member 3 and flows out to the rear, which helps to increase the turning resistance of the hull 1, with an improvement in course stability of the hull 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ship provided with a skeg (center skeg) at the stern along a hull center line, and in particular, a marine vessel course stabilizing apparatus capable of improving course stability by providing an additional material to the skeg. About.
[0002]
[Prior art]
In general, a hull type in which the stern stern bottom gradually rises rearward is equipped with a skeg to stabilize the course.
In order to sufficiently improve the stability of the course, the skeg is conventionally enlarged.
[0003]
[Problems to be solved by the invention]
By the way, if the skeg is enlarged as described above, the needle keeping performance of the ship is improved, but the arrangement of the pod propeller and the like behind the skeg is hindered, and the hull resistance is increased due to an increase in the inundation area of the skeg. There is a problem of doing.
Therefore, the present invention provides an additional material at the rear end of the skeg at the stern to facilitate the generation of a vortex from the rear end of the skeg during navigation, thereby improving the course stability of the hull. An object of the present invention is to provide a ship course stabilizing device.
[0004]
[Means for Solving the Problems]
In order to solve the above-described problems, a ship course stabilizing device of the present invention includes a skeg protruding along the hull center line below the stern bottom, and at least at the rear end of the skeg, the left and right sides from the lower edge thereof. A symmetrically and horizontally protruding plate-like member is provided.
[0005]
Further, in the boat course stabilizing device of the present invention, the plate-shaped member is fitted into a notch formed at a rear lower end of the skeg, and is fixed so as not to protrude below a lower edge of the skeg. It is characterized by having.
[0006]
Further, in the boat course stabilizing device of the present invention, the plate-shaped member has a streamlined cross section.
[0007]
Further, the course stabilizing device for a marine vessel according to the present invention is characterized in that the plate-shaped member is provided with movable flaps which can be individually operated on the left and right sides of a rear edge thereof.
[0008]
In the above-described ship course stabilizing device of the present invention, during navigation, a vortex is generated and flows backward from the skeg provided with the plate-shaped member at the stern, and the skew increases, thereby increasing the turning resistance of the hull. As a result, the course stability of the hull is improved.
[0009]
Since the plate-like member is provided so as to symmetrically and horizontally project from the lower edge of the rear end of the skeg into left and right water, the vortex is generated at a relatively deep water depth position. Without affecting the propulsion unit behind the skeg.
[0010]
Further, when the plate-shaped member is provided so as to be fitted into a notch formed at a rear lower end of the skeg so as not to protrude below the lower edge of the skeg, the plate-shaped member is separated into left and right bodies. It is possible to obtain an advantage that the plate-like member does not hinder the docking of the hull, while being advantageously configured as a single unit without strength.
[0011]
Further, when the plate-shaped member has a streamlined cross section, generation and outflow of vortices from the rear end of the skeg (particularly, both ends of the plate-shaped member) due to the mounting of the plate-shaped member are prevented. While promoting, the increase in resistance due to the presence of the plate-like member itself can be greatly reduced.
[0012]
Furthermore, if the plate-shaped member is provided with movable flaps that can be individually operated on the left and right sides of the rear edge, for example, when the hull tends to turn to the starboard side under the influence of waves, The asymmetrical flow that lowers the flow velocity by operating only the movable flaps on the port side provides a stable force to return the bow to the normal direction, and simultaneously raises the left and right movable flaps upward when the stern rises. By pivoting the movable flap downward when the stern descends, pitching of the hull can be positively suppressed.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, a ship course stabilizing device as an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a stern portion of a ship provided with the device, and FIG. FIG. 3 is a side view of a main part showing a modification of the plate-like member in the above apparatus, FIG. 4 is a side view of a main part showing another modification of the plate-like member in the above-mentioned apparatus, and FIG. It is an arrow B bottom view.
[0014]
First, a ship course stabilizing device according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. A skeg 2 protruding along is provided.
[0015]
Further, a plate-like member 3 is provided which projects symmetrically and horizontally from the rear lower end of the skeg 2 into the left and right water. In the present embodiment, the projecting members 3b are provided diagonally upward at both left and right ends of the plate-shaped member 3, but these projecting members 3b may be omitted. Further, the plate-like member 3 may be provided entirely from the front lower end to the rear lower end of the skeg 2.
[0016]
Further, a pod propeller 4 hanging from the hull 1 is provided at the rear of the skeg 2 so as to be pivotable about a vertical axis 5. The pod propeller 4 uses a gas turbine drive or a diesel engine (not shown) on the ship. The motor in the pod 4a is operated by the electric power supplied from the driving generator, and the motor drives the propeller 4b to rotate.
[0017]
In a modification of the present embodiment shown in FIG. 3, the plate-shaped member 3 is fitted into a notch 2 a formed at the rear lower end of the skeg 2, and the plate-shaped member 3 is located below the lower edge of the skeg 2. Although fixed so as not to protrude, in this case also, the plate member 3 is provided so as to symmetrically and horizontally project from the skeg 2 into the left and right water.
[0018]
Further, in the modification shown in FIG. 4, a plate-like member 3 fitted into a notch 2a formed at the rear lower end of the skeg 2 has movable flaps 3a which can be individually operated on the left and right sides of the rear edge, respectively. And has a streamlined cross section as a whole as shown in the figure. The rotation of each movable flap 3a is controlled by controlling flap driving means (not shown) provided in the fixed portion of the flap 3 based on detection signals from a turning sensor and a pitch sensor of the hull.
[0019]
In the course stabilizing device for a marine vessel of the present embodiment described above, during navigation, a vortex is generated rearward from the rear end of the skeg 2 provided with the plate-shaped member 3 at the stern, and flows out. Since the resistance is increased, the course stability of the hull 1 is improved as a result.
[0020]
And since the plate-shaped member 3 is provided so as to protrude into the left and right water from the lower edge of the rear end of the skeg 2, the vortex is generated at a relatively deep water depth position, and the vortex is generated behind the skeg 2. There is no adverse effect on the propulsion device.
[0021]
When the plate-shaped member 3 is provided so as to be fitted into a notch 2a formed at the lower end of the rear end of the skeg 2 so as not to protrude below the lower end edge of the skeg 2, the plate-shaped member 3 may be left and right. It is possible to obtain the advantage that the plate-shaped member 3 does not hinder the docking of the hull, while being advantageously constructed as an integral body without being separated.
[0022]
Further, when the plate-shaped member 3 has a streamlined cross section, the rear end of the skeg 2 (particularly in the vicinity of the joint with the plate-shaped member 3) or the plate-shaped member 3 due to the mounting of the plate-shaped member 3 An increase in resistance due to the presence of the plate-like member 3 itself can be greatly reduced while promoting the generation and outflow of vortices backward from both ends and the like.
[0023]
Furthermore, when the plate-shaped member 3 is provided with movable flaps 3a that can be individually operated on the left and right sides of the rear edge, for example, when the hull tends to turn to the starboard side under the influence of waves. The asymmetric flow of lowering the velocity by operating only the movable flaps on the port side provides a stable force to return the bow to the normal direction, and simultaneously moves the left and right movable flaps 3a when the stern rises. By pivoting the movable flap 3a downward when the stern descends, pitching of the hull 1 can also be positively suppressed.
[0024]
【The invention's effect】
As described above in detail, the following effects can be obtained by the marine course stabilizing device of the present invention.
(1) At the stern, a plate-like member that protrudes symmetrically and horizontally into at least the left and right water from at least the rear end of the skeg along the hull center line is provided. A vortex is generated and flows backward from the skeg, and the turning resistance of the hull is increased accordingly. As a result, the course stability of the hull is improved. And since the said plate-shaped member is provided so that it may protrude into the right and left water from the lower edge part of the rear end of the said skeg, the said vortex will be generated at a relatively deep water depth position, There is no adverse effect on the propulsion device.
(2) When the plate-shaped member is provided so as to be fitted into a notch formed at the rear lower end of the skeg so as not to protrude below the lower edge of the skeg, the plate-shaped member is separated into left and right parts. It is possible to obtain an advantage in that the plate-shaped member does not hinder the docking of the hull while being advantageously configured as an integral body without having to do so.
(3) When the plate-shaped member has a streamlined cross section, the generation and outflow of vortices from the rear end of the skeg (particularly, both ends of the plate-shaped member) due to the mounting of the plate-shaped member. , The increase in resistance due to the presence of the plate-shaped member itself can be greatly reduced.
(4) If the plate-like member has movable flaps which can be individually operated on the left and right sides of the rear edge, for example, when the hull tends to turn to the starboard side due to the influence of waves, The asymmetrical flow that lowers the flow velocity by operating only the movable flaps on the port side provides a stabilizing force to return the bow to the normal direction, and simultaneously moves the left and right movable flaps when the stern rises. By rotating the movable flap downward when the stern descends, the pitching of the hull can be positively suppressed.
[Brief description of the drawings]
FIG. 1 is a side view of a stern of a ship provided with a ship course stabilizing device as one embodiment of the present invention.
FIG. 2 is a sectional view taken along the line AA of FIG. 1;
FIG. 3 is a side view of a main part showing a modified example of a plate-like member in the boat course stabilizing device of FIGS.
FIG. 4 is a main part side view showing another modified example of the plate-like member in the boat course stabilizing device of FIGS.
FIG. 5 is a bottom view as viewed in the direction of arrows BB in FIG. 4;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 hull 1 a stern bottom 2 skeg 2 a notch 3 plate-like member 3 a movable flap 3 b projecting member 4 pod propeller 4 a pod 4 b propeller 5 vertical axis

Claims (4)

A skeg protruding along the center line of the hull below the stern hull, and at least at the rear end of the skeg, a plate-like member is provided that symmetrically and horizontally projects horizontally from the lower edge into left and right water. A ship course stabilizing device, characterized in that: 2. The plate-like member according to claim 1, wherein the plate-shaped member is fitted into a notch formed in a rear lower end of the skeg, and is fixed so as not to protrude below a lower edge of the skeg. The course stabilizing device for a ship according to the above. The course stabilizing device for a ship according to claim 1 or 2, wherein the plate-shaped member has a streamlined cross section. The course stabilizing device for a boat according to any one of claims 1 to 3, wherein the plate-shaped member includes movable flaps that can be individually operated on the left and right sides of a rear edge portion, respectively.

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