GB2137564A - Flat-bottomed vessel - Google Patents

Abstract

A vessel hull structure has a flat bottom 9 and lefthand and righthand side plates 2 with lower extensions 5 projected downward from the bottom so that the body of the vehicle has a H-shaped cross-sectional configuration of which lower half has a substantially reduced length. The bow portion 3 includes a flat bow plate 3-1 which extends forward in an upward inclination angle whereby water located in front of the vehicle is introduced into a space defined by the bottom plate and the side plates as it moves forward so that a floating pressure generating flow is developed therein. Further, the side plates 2 each include another extension 6 projected forward of the bow plate and downward of the bottom plate; said side plates extend vertically at a right angle relative to the bottom plate, whereby water introduced into the space below the bottom is divided into inside and outside streams. <IMAGE>

Description

SPECIFICATION Improved hull structure for a water moving vehicle such as ship, boat or the like Background of the invention 1. Field of the invention The present invention relates to an improved hull structure for a water moving vehicle such as ship, boat or the like and more particularly to a hull structure which is constructed such that water located in front of the vehicle is introduced into the space below the bottom toward the stern portion as it moves forward by operating a propelling means so that high speed movement is assured under very few resistance without any impact imparted thereto.

2. Description ofthe prior art A hitherto known water moving vehicle such as ship, boat or the like (hereinafter referred to simply as ship) is generally constructed such that it moves forward on water while thrusting water aside by means of a bow portion comprising side plates forming an inverted V-shaped configuration with an acute angle contained therebetween as seen from the above and a V-shaped configuration as seen in a cross-section and extending rearward toward a stern portion and a bottom having a semicircular crosssectional configuration.The so-called streamline shaped construction of the bow portion of the conventional ship causes a depth of a water line to become increased and therefore area of the side plates below the water surface is substantially enlarged whereby the ship is exposed to remarkably high resistance and impact while it is advancing on water. Specifically, it has been found with respect to the conventional ship having a streamline shaped configuration in the bow portion that a major part of propulsive force generated by a propelling means such as propeller or the like means disposed in the stern portion is consumed in vain for damping impact and overcoming water resistance during the forward movement of the ship on water and therefore it becomes difficult to assure high speed advancement of the ship on water.This means that a ratio of useless fuel consumption against impact and resistance to total fuel consumption during the forward movement of the ship on water is raised up to a high level.

Another problem pointed out with respect to the hull structure of the conventional ship is that a bending moment appears along one of the side plates having a wide working area below the water line when lateral waves collide against it, said bending moment being attributable mainly to difference in geometrical configuration of both the bow and body portions and tending to warp the whole body of the ship relative to the longitudinal axis thereof. In an extreme case where very intensive bending moment is active along the side plate there is a danger of developing crack in the boundary area between the bow and body portions of the ship, resulting in tragic sinking thereof.

In view of the foregoing problems as mentioned above with respect to the conventional hull structure of a ship requests for developing an improved and advanced hull structure have been raised by ship owners which makes it possible to assure high speed movement of a ship on water with substantially reduced useless fuel consumption and moreover has no danger of causing breakage or damage on the ship when the latter is exposed to the influence imparted by lateral waves.

Summary of the invention The present invention is intended to obviate all of the foregoing problems as mentioned above with respect to the conventional hull structure for a water moving vehicle such as ship, boat or the like.

It is an object of the present invention to provide an improved hull structure for a water moving vehicle such as ship, boat or the like which asures remarkable reduction in water resistance which has adverse effect on fuel consumption and makes it posible to move it forward on water without impact imparted thereto.

It is other object of the present invention to provide an improved hull structure for a water moving vehicle which is constructed so as to develop a hull floating pressure generating flow in the space below the bottom by allowing water in front of the vehicle to be introduced thereinto.

It is another object of the present invention to provide an improved hull structure for a water moving vehicle which is constructed so as to divide introduced water into inside and outside streams before developing the floating pressure generating flow in the space by the inside stream.

It is further another object of the present invention to provide an improved hull structure for a water moving vehicle which is constructed so as to allow the vehicle to move on water as if it slies thereon by utilizing inertia force of the vehicle after the latter has been floated on water.

To accomplish the objects as mentioned above, there is proposed in accordance with the invention an improved hull structure for a water moving structure such as ship, boat or the like which essentially comprises in combination a bow portion including a flat bow plate and forward extensions from lefthand and righthand side plates, said bow plate extending forward in a certain upward inclination angle, a body portion including a flat bottom plate and lefthand and righthand side walls fixedly secured to said bottom plate at a right angle, said bottom plate forming a continuation from the bow plate and extending rearward in the horizontal direction and said side plates having a lower extension projected downward from the bottom plate by a predetermined distance respectively so that the body portion has a H-shaped configuration as seen in a cross-sectional plane of which lower half has a substantially shortened length,and a stern portion including a propelling means such as propeller or the like for forward movement of the vehicle, said stern portion being opened in the rearward direction.

In a preferred embodiment of the invention the lefthand and righthand side plates extend linearly rearward from the bow portion to the stern portion in the longitudinal direction of the vehicle.

The side plates extend at a right angle relative to the bottom plate, that is, in the vertical direction.

Further, the side plates have another extension projected forward of the bowplate and downward of the bottom plate respectively.

Features and advantages of the present invention will become apparent from the reading of the following description made in conjunction with the accompanying drawings.

Brief description of the accompanying drawings The accompanying drawings will be briefly described below.

Figure lisa schematic plan view of a hull structure in accordance with the present invention.

Figure 2 is a vertical sectional view of the hull structure in Figure 1.

Figure 3 is a cross-sectional view of the hull structure taken in line lli - lil in Figure 2.

Detailed description of the preferred embodiments Now, the present invention will be described in a greater detail with reference to the accompanying drawings which illustrate preferred embodiments of the invention.

As is apparent from figure 1, a ship 1 has a - rectangular configuration as seen from the above and therefore does not include a streamline-shaped bow portion with an acute angle at the foremost end part thereof as is the case with a conventional ship.

Referring to Figure 2, the bow portion 3 includes an upwardly inclined flat bow plate 3-1 and in continuation to the latter a bottom 9 extends horizontally to a stern portion 4. Below the stern portion 4 is disposed a screw 8 adapted to be rotated by an engine (not shown), and a part located above the screw 8 is constituted by a stern plate 4-1 in the conventional manner. Lefthand and righthand side plates 2 are flat and extend in parallel to the longitudinal axis of the ship. As is apparent from the drawings, the lower part 5 of the side plates 2 is projected downward by a predetermined distance and furthermore it is projected also forward of the bow plate 3-1.The extension 6 from both the side plates 2 extending forward of the bow plate 3-1 serves to divide introduced water into inside and outside streams which is brought in the area aground the bottom ofthe ship as it moves forward. Further, the inside stream is further introduced into the space 10 as defined by the downward extensions 5 and the bottom 9 whereby a hull floating pressure generat ing water flow is generated in the aforesaid space 10 which is effective in lifting the hull 1 to float up on water.

Since the hull of the ship is constructed in the above-described manner, the ship moves forward on water as the screw 8 is-rotated at a high rotational speed, while dividing water located in front of the ship into inside and outside streams by means of the forward extensions 6 from the side plates 2, so that the inside stream is introduced into the space 10 defined by the downward extensions 5 and the bottom 9. Specifically, since the bow plate 3-1 extends rearward in a downward inclination to form a continuation to the bottom 9 in the horizontal plane, water which has collided against the bow plate 3-1 flows rearward in the downward inclination along the bow plate 3-1 and then generates a hull floating pressure generating water flow in the space below the bottom 9.Due to the arrangementthat the aforesaid floating pressure generating water flow is inhibited from escaping in the transverse direction by means of the downward extensions 5 from the side plates 2 it is assured that the bow portion 3 is floated up above the water surface and thereby the whole body ofthe ship 1 is raised thereabove. After the floating pressure generating flow has contributed to floatation of the hull, it is discharged rearward from the open area in the stern portion 4.

As described above, the bow portion 3 is designed in the rectangular configuration as seen from the above with the flat 3-1 extending forward in the upward inclination but not in the conventional streamline-shaped configuration having an acute angle at the foremost end part of the ship and thereby it is assured that water is divided into inside and outside streams by means of the downward extensions 5 relative to the side walls 2 without any impact exerted on the bow portion 3 as the ship moves forward and thereafter the inside stream is introduced into the space as defined by the bottom 9 and the downward extensions 5to develop a hull floating pressure generating flow therein. As a result the improved hull structure of the invention makes it possible to move the ship at a high speed under substantially reduced resistance.More specifically, the present invention consists in that a high level impact imparted to the hull of the conventional ship as it moves forward at a high speed is converted into the aforesaid floating pressure generating flow which is effective in lifting the hull and thereby it becomes possible to move the ship under remarkably reduced resistance without any impact imparted thereto.

As will be readily understood from the above description, it is possible to move a ship under substantially reduced resistance without any impact imparted thereto by properly determining a corelation among lines (extensions 5 and 6 from both the lefthand and righthand side walls 2), plane (bow plate 3-1), dead weight of the ship and moving speed.

Since the improved hull structure of the present invention as constructed described above develops a high intensity of floating pressure in the space below the bottom irrespective of size of a ship, it is assured that the ship advances on water smoothly with economic consumption of fuel accompanied.

Once the hull of the ship has been floated on water, it moves forward while maintaining its hull in the stable state under the influence of inertia force given by the hull of the ship as if it slides thereon. Thus, the improved hull structure ofthe invention has an excellently high economy from the viewpoint of energy consumption.

Since the hull structure of the invention is not subjected to a high intensity of resistance and impact as are case with the conventional ship, it can enjoy a number of advantageous features of increased moving speed, reduced consumption of fuel, substantial reduction in operating costs, increased loading capacity in a ship, reduced depth below the water line, increased stability of ship and others.

The present invention has been described above with respect to a preferred embodiment, but it should be of cource understood that the present invention should be not limited only to this and many changes or modifications may be made in a suitable manner without any departure from the spirit and scope of the invention.

Claims (4)

1. In hull structure for a water moving vehicle such as ship, boat or the like the improvement comprising in combination; a bow portion (3) including a flat bow plate (3-1) and forward extensions from lefthand and righthand side walls (2), said bow plate (3) extending forward in a certain upward inclination angle, a body portion including a flat bottom plate (9) and lefthand and righthand side walls (2) fixedly secured to said bottom plate (9) at a right angle, said bottom plate (9) forming a continuation from the bow plate (3-1) and extending rearward in the horizontal direction and said side plates having a lower extension (5) projected downward from the bottom plate (9) by a predetermined distance respectively so that the body portion has a H-shaped cross-sectional configuration of which lower half has a substantially reduced length, a stern portion (4) including a propelling means for moving the vehicle forward, said stern portion (4) being opened in the rearward direction.

2. A hull structure as defined in claim 1, wherein the side walls (2) extend linearly from the bow portion (3) to the stern portion (4) in the longitudinal direction of the vehicle.

3. A hull structure as defined in claim 1, wherein the side walls (2) have an extension (6) projected forward of the bow plate (3-1 ) and downward of the bottom plate (4) respectively.

4. A hull structure as defined in claim 1, wherein the side plates (2) extends vertically at a right angle relative to the bottom plate (9).