JP3332571B2 - Anti-vibration stern shape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stern shape of a ship having a propeller and a rudder at the stern.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 9 and 10, in a conventional ship having a single propeller 2 and a single rudder 1 at the stern, a transverse section 4 of a hull 6 at the position of the propeller 2 is known.
However, just above the propeller 2, it has a hull portion 6 a submerged below the full load draft line 5. In addition, the code | symbol 3 in a figure shows a propeller rotation surface, and the code | symbol 7 shows a propeller boss. Fig. 12 (front view of the rear half of the hull) and figure
Also in the case of a conventional two-shaft two-rudder boat as shown in FIG. 13 (sectional view taken along the line EE in FIG. 12), the hull portion 6a is located directly below the rotating surfaces 3a and 3b of the left and right propellers and below the full load draft line 5. have.

[0003]

By the way, in a conventional ship as shown in FIGS. 9 and 10, the vibrating force of the propeller 2 causes the submerged hull portion 6a at the stern using water as a medium.
And may cause large hull vibrations in some cases. Also, from the viewpoint of the propulsion performance of the ship, it may be desired to increase the diameter of the propeller 2 as much as possible. However, if the hull 6a is submerged under the full draft line just above the propeller 2, the propeller 2 is enlarged. There is a problem that it is not possible and disadvantageous in terms of propulsion performance.

Therefore, as shown in FIG. 11, a hull portion 6b immediately above the propeller 2 at the stern is provided above the full draft line 5 so that the diameter of the propeller 2 can be made sufficiently large. It is also conceivable to prevent the vibrating force of the propeller 2 from being transmitted to the hull using water as a medium. In this case, the rudder 1 is submerged to the hull above the full draft line 5. It is necessary to lengthen the rudder shafts for mounting, and this causes a problem of increasing the weight and insufficient strength of the hull near the stern.

The conventional two-shaft two-rudder ship as shown in FIGS. 12 and 13 also has the same problems as the above-mentioned single-shaft two-rudder ship. The present invention is intended to solve the above-mentioned problems, and it is intended to prevent the vibrating force of the propeller at the stern from being transmitted to the hull as much as possible so that the rudder behind the propeller can be easily attached to the hull. It is an object of the present invention to provide a vibration-proof stern shape.

[0006]

In order to achieve the above object, the vibration-proof stern shape of the present invention is applied to a ship provided with a propeller at the stern and having a rudder rearward from the propeller. In order to suppress vibration of the hull near the propeller due to vibration, the shape of the stern has an outer surface of the hull that is concavely curved above the full draft line just above the propeller, and at the mounting part of the rudder It is characterized by having a hull outer surface that is curved downward below the full draft line.

In the vibration-proof stern shape of the present invention, the propeller has a center of rotation on the hull center line, and has a rudder on each of the left and right sides behind the propeller. The hull shape near the line is formed in a concave shape that is recessed above the full draft line in the hull portion near the hull center line, and the left and right hull portions equipped with the rudder respectively project below the full draft line It is characterized by being formed in.

Further, in the vibration-proof stern shape of the present invention, the propellers are arranged in a pair on the left and right, and the outer surface of the hull which is concavely curved above the full draft line immediately above each of the propellers is provided. A pair of left and right rudders are formed on both sides of the hull center line, and between the rotation centers of the left and right propellers, rearward of the propellers so as to diverge downward from each other. A common convexly curved outer surface of the hull, which is curved downward from the full draft line so as to have portions on both sides, is formed near the hull center line.

The anti-vibration stern shape of the present invention is characterized in that the propellers are arranged in pairs on the left and right, and a hull portion that is concavely curved above the full draft line near each of the propellers is provided. With a common concavely curved hull outer surface on both sides, a pair of left and right rudders are provided rearwardly of the propeller so as to diverge upward from each other. Also, the outer surface of the hull which is curved downward is formed on both sides of the outer surface of the hull.

[0010] Further, in the vibration-proof stern shape of the present invention, the propellers are arranged in pairs on the left and right, and the outer surface of the hull which is concavely curved above the full draft line immediately above each of the propellers is provided. The rudder is formed on both sides of the hull center line, and a rudder is provided along the hull center line behind the propeller, and the outer surface of the hull having the mounting portion of the rudder is below the full draft line near the hull center line. It is characterized by being formed to be convexly curved.

[0011] In the vibration-proof stern shape of the present invention, the propellers are arranged in a pair on the left and right, and a hull portion that is concavely curved above the full draft line immediately above each of the propellers is provided. With a common concavely curved hull outer surface on both sides, a pair of left and right rudders are provided rearward of the propeller in parallel with the hull center line, and each of these rudders has a mounting portion below the full load draft line. It is characterized in that a convexly curved hull outer surface is formed on both sides of the concavely curved hull outer surface.

[0012]

In each of the above-mentioned anti-vibration stern shapes of the present invention, there is no hull portion submerged immediately above the propeller in any case, so that the propeller vibrating force is prevented from being transmitted to the hull using water as a medium during navigation. However, the propulsion operation is performed using a propeller having a sufficiently large diameter for improving the propulsion performance.
Further, since the position where each rudder is lowered can be set to a position lower than the full draft line, the length of the rudder shafts may be the same as the conventional one, and the weight does not increase.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a vibration isolating stern shape of a single-shaft two-rudder boat as a first embodiment, and FIG. 2 is a front view of the rear half of the hull, and the center of rotation of the propeller 2 at the stern of the hull 6 is on the hull center line CL, as is apparent from the propeller rotation surface 3 shown in FIG.
A pair of rudders 1, 1 are arranged on the left and right behind the propeller 2, respectively.

The hull cross section 4 at the position of the propeller 2
Hull form in the vicinity of the full water line 5 in are formed in the concave curvature type recessed above the full water line 5 in the hull portion 6c in the vicinity of the hull centerline CL, the left and right hull 6d of the propeller 2, 6d Each is formed in a convex curve shape protruding downward from the full draft line 5. As shown in FIG. 1, the left and right rudder 1, 1 are respectively left and right hull portions 6d ', 6 which are curved below the full load draft line 5.
The hull portions 6d ', 6d' are formed so as to be continuously and smoothly formed rearward from the hull portions 6d, 6d on the left and right of the propeller position. .

Further, the rudder area of each rudder 1, 1 is about half that of the conventional single rudder type because it is a two rudder type. That is, the rudder 1 is configured to enter the propeller rotating surface 3. The diameter of the propeller 2 is made sufficiently large to be about 90% of the full draft d because there is no submerged hull portion immediately above the propeller 2, and the upper end of the propeller 2 is not exposed from the full draft line 5. And the lower end of the propeller 2 is set so as not to be lower than the level of the bottom of the ship.

Since the anti-vibration stern shape of the uniaxial two rudder ship as the first embodiment is configured as described above, the propeller 2
There is no submerged hull directly above the hull.This prevents the propeller motive force from propagating to the hull using water as a medium during navigation, while using a propeller with a sufficiently large diameter to improve propulsion performance. Can be promoted.

The position where each rudder 1 is lowered is a full draft line 5.
Therefore, the length of the rudder shafts may be the same as the conventional one, and the weight does not increase. And
Since the rudder 1 is completely immersed in the wake of the propeller, it is possible to secure sufficient steering. In this example, as a result of the trial calculation, the reduction rate of the hull vibration due to the propeller vibrating force is about 30%, and the required horsepower saving effect by increasing the diameter of the propeller is about 15%.

Next, a description will be given of a vibration-proof stern shape of a two-axis two-rudder ship as a second embodiment of the present invention. FIG. 3 is a front view of the rear half of the hull, and FIG. FIG.
In the second embodiment shown in FIGS. 3 and 4, the propeller rotating surfaces 3a, 3b and the propeller bosses 7a,
The propellers 2a indicated by 7b are arranged in pairs on the left and right, and the hull outer surfaces 6f, 6f that are concavely curved above the full draft line 5 immediately above each of the propellers 2a.
Are formed on both sides of the hull center line CL.

A pair of left and right rudder 1 is located behind the propellers between the rotation centers of the right and left propellers 2a.
a and 1b are provided so as to be spread downwardly and to be present in the wake of the propeller.
A common convexly curved hull outer surface 6e that is curved below the full draft line 5 so as to have the mounting portions a and 1b is formed near the hull center line CL.

In the case of the vibration-proof stern shape of the second embodiment described above, there is no submerged hull immediately above the left and right propellers 2a, so that the propeller vibrating force reduces water during navigation. Propulsion can be performed by the propeller 2a having a sufficiently large diameter (increased to about 90% of full draft) to improve propulsion performance while suppressing transmission to the hull as a medium.
The position where each of the left and right rudders 1a and 1b is lowered is lower than the full load draft line 5, and the two rudders 1a and 1b which are completely immersed in this way are arranged downwardly and divergently so as to be behind the propeller. Since it is present in the flow, it is possible to secure sufficient steering while keeping the length and weight of the rudder shafts almost the same as before.

FIG. 5 (front view of the rear half of the hull) and FIG.
(D-D sectional view in FIG. 5) shows a vibration-isolating stern shape as a third embodiment of the present invention, in which the propeller rotating surfaces 3a and 3b and the propeller bosses 7a and 7b are provided at the stern of the hull 6.
Are arranged in pairs on the left and right, and a common concavely curved hull outer surface having on both sides a hull portion curved right above the full draft line 5 immediately above each of the propellers 2a It has 6f.

A pair of left and right rudders 1a and 1b are provided so as to be divergent upward and distant from each other behind the propellers 2a so as to be present in the wake of the propellers. Convex hull outer surfaces 6e, 6e having an attachment portion and convex below the full load draft line 5 are formed on both sides of the concave hull outer surface 6f, respectively. The anti-vibration stern shape according to the third embodiment can obtain substantially the same operation and effect as the above-described second embodiment by the above configuration.

Next, a description will be given of an anti-vibration stern shape according to a fourth embodiment of the present invention. FIG. 7 is a front view of a rear half of a hull having the same stern shape.

In the fourth embodiment, only one rudder 1 is provided along the hull center line CL in a stern shape substantially similar to that of the second embodiment (see FIGS. 3 and 4). . That is, also in this stern shape, the propeller rotating surfaces 3 a and 3 b and the propeller boss 7 are provided at the stern of the hull 6.
The propellers indicated by a and 7b are arranged in pairs on the left and right, and the hull outer surfaces 6f and 6f which are concavely curved above the full draft line 5 immediately above each of the propellers are connected to the hull centerline CL. It is formed on each side.

One rudder 1 is provided along the hull center line CL behind the propeller, and a hull outer surface 6e having a mounting portion for the rudder 1 is closer to the full draft line 5 near the hull center line. It is formed so as to curve downward. In the anti-vibration stern shape of the fourth embodiment described above, the rudder 1 is not disposed in the wake of the propeller as compared with the second embodiment described above.
Can be fully submerged under the water surface without inducing the extension of the rudder shaft, and the same operational effects as in the second embodiment can be achieved with respect to suppression of hull vibration and improvement of propulsion performance by increasing the diameter of the propeller. Can be obtained.

FIG. 8 (a front view of the rear half of the hull) shows a vibration-proof stern shape as a fifth embodiment of the present invention, and the fifth embodiment is the same as the third embodiment (FIGS. 5 and 5). 6), the left and right rudders 1a and 1b are provided in parallel with the hull center line CL. That is, also in the case of this stern shape, the propeller rotating surfaces 3a and 3b and the propellers 2a indicated by the propeller bosses 7a and 7b are arranged on the stern of the hull 6 in a pair on the left and right.
It has a common hull outer surface 6f having a hull portion curved above the full draft line 5 directly above each of the propellers 2a on both sides.

Further, a pair of left and right rudders 1a and 1b are provided behind each propeller. These rudders are all arranged vertically in parallel with the hull center line.
As the mounting portions a and 1b, a convexly curved hull outer surface 6e that is convexly curved below the full load draft line 5 is formed on both sides of the concavely curved hull outer surface 6f, respectively.

As described above, in the vibration-proof stern shape of the fifth embodiment, although the rudders 1a and 1b are not disposed in the wake of the propeller, the rudder shaft Each rudder 1a, 1b can be completely submerged below the surface of the water without extending the length of the hull, and the improvement of the propulsion performance by suppressing the hull vibration and increasing the diameter of the propeller is the same as in the third embodiment. Action and effect can be obtained.

Each of the second to fifth embodiments of the present invention shows the anti-vibration type stern shape of the twin-axle ship. As in the case of the stern shape, as a result of the calculation, the reduction rate of the hull vibration due to the propeller vibrating force was about 30%, and the required horsepower saving effect by increasing the diameter of the propeller (about 90% of full load draft) was about 15%.

[0030]

As described in detail above, according to the vibration-proof stern shape of the present invention, the following effects can be obtained. (1) The hull just above the propeller is concave so that there is no submerged hull just above the propeller at the stern.
Since the outer surface of the hull is provided, it is possible to use a propeller having a sufficiently large diameter for improving propulsion performance while suppressing transmission of the propeller vibrating force to the hull using water as a medium during navigation. (2) The hull of the stern at the stern is convexly curved so that it is lower than the full draft line (ie, submerged).
As they may have a the hull outer surface, it does not lead to increase in weight for steering shaft, and the like.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an anti-vibration stern shape of a single-shaft two-rudder ship as a first embodiment of the present invention, wherein a part shown by a solid line shows a section AA in FIG. 2, and a part shown by a broken line Shows a BB cross section of FIG.

FIG. 2 is a front view of the rear half of the hull of the single-shaft two-rudder boat of FIG. 1;

FIG. 3 is a front view of the rear half of the hull of a two-axis two-rudder boat having a vibration-isolating stern shape as a second embodiment of the present invention.

FIG. 4 is a sectional view taken along the line CC of FIG. 3;

FIG. 5 is a front view of the rear half of the hull of a twin-axle two-rudder boat having a vibration-isolating stern shape as a third embodiment of the present invention.

FIG. 6 is a sectional view taken along line DD of FIG. 5;

FIG. 7 is a front view of the rear half of the hull of a two-axis single rudder ship having a vibration-isolating stern shape as a fourth embodiment of the present invention.

FIG. 8 is a front view of a rear half of a hull of a twin-axle two-rudder boat having a vibration-isolating stern shape as a fifth embodiment of the present invention.

FIG. 9 is a side view showing the stern shape of a conventional uniaxial one rudder ship.

10 is a front view of the rear half of the hull of the single-shaft one-rudder boat in FIG. 9.

FIG. 11 is a side view showing another example of the stern shape of the conventional uniaxial one rudder boat.

FIG. 12 is a front view of the rear half of the hull of a conventional two-axis two-rudder boat.

FIG. 13 is a sectional view taken along the line EE of FIG. 12;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rudder 2, 2a Propeller 3, 3a, 3b Propeller rotating surface 4 Hull transverse section at propeller position 5 Full draft line 6 Hull 6c Hull part right above propeller 6d Hull part at right and left of propeller 6d 'Hull part at right and left rudder mounting position 6e Outer surface of convexly curved hull 6f Outer surface of concavely curved hull 7, 7a, 7b Propeller boss 8a Propeller shaft

Claims (6)

(57) [Claims] In a marine vessel having a propeller at the stern and a rudder rearward of the propeller, the shape of the stern is designed to suppress vibration of a hull near the propeller due to the vibrating force of the propeller. In addition to having a hull outer surface that is concavely curved above the full draft line just above the propeller, and having a hull outer surface that is convexly curved below the full draft line at the mounting part of the rudder, Anti-vibration stern shape. 2. The vibration isolating stern shape according to claim 1, wherein a center of rotation of the propeller is on a hull center line, and each of the propellers is steered to the left and right behind the propeller.
The hull shape near the full draft line in the hull cross section at the propeller position is formed in a concave shape that is recessed above the full draft line in the hull part near the hull center line, and the left and right hull parts to which the rudder is attached are respectively An anti-vibration stern shape characterized by being formed to protrude downward from the full draft line. 3. The anti-vibration stern shape according to claim 1, wherein the propellers are arranged in a pair on the right and left, and each of the propellers is concavely curved above a full load draft line immediately above each of the propellers. Hull outer surfaces are formed on both sides of the hull center line, respectively, and a pair of left and right rudders are provided between the rotation centers of the left and right propellers behind the same propeller so as to be divergent downward. An anti-vibration stern shape, characterized in that a common convexly curved outer surface of the hull, which is curved downward from the full draft line so as to have the rudder mounting portions on both sides, is formed near the hull center line. 4. The anti-vibration stern shape according to claim 1, wherein the propellers are arranged in a pair on the left and right, and each of the propellers is curved right above each of the propellers above the full load draft line. With a common concavely curved hull outer surface having hull portions on both sides, and a pair of left and right rudders rearwardly extending beyond the propeller so as to diverge upward from each other. An anti-vibration stern shape, characterized in that a convexly curved hull outer surface curved downwardly below the full draft line is formed on both sides of the concavely curved hull outer surface, respectively. 5. The anti-vibration stern shape according to claim 1, wherein the propellers are arranged in a pair on the left and right, and each of the propellers is concavely curved above the full draft line immediately above each of the propellers. The hull outer surface is formed on both sides of the hull center line, and a rudder is provided along the hull center line behind the propeller, and the hull outer surface having the mounting part of the rudder is fully loaded near the hull center line and the draft line is provided. An anti-vibration stern shape characterized by being formed so as to be convex downwardly. 6. The anti-vibration stern shape according to claim 1, wherein the propellers are arranged in a pair on the left and right, and each of the propellers is concavely curved above a full load draft line immediately above each of the propellers. With a common concavely curved hull outer surface having hull portions on both sides, a pair of left and right rudder rearward of the propeller, each parallel to the hull center line, An anti-vibration stern shape, characterized in that a convexly curved hull outer surface convexly curved below a line is formed on each side of the concavely curved hull outer surface.