JPH07165176A - High speed ship trim restraint system - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the trim from becoming excessive by additionally (assisting) generating buoyancy or lift on the trim suppressing projections that are integrally or additionally provided on the bottom of the stern ship. (EN) Provided is a trim suppressing device for a high-speed ship, which facilitates a gliding state or a take-off. [Configuration] A substantially constant wedge shape extending from near the hull centerline 5 on the stern bottom surface 7 to the port side, that is, a lift-type trim suppressing device A that is inclined substantially linearly downward toward the stern in a side view. One projection a and a projection b related to the lift and buoyancy combined type trim suppression device B having a wedge-shaped side cross section, which is continuous with the rear end surface of the first projection a and inclines downward substantially linearly toward the stern. To line up. At the port side position, the cross-sectional shapes of the both present one wedge (triangle) shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention relates to a sliding condition in a high speed range (
Hydroplaning condition) or improvement of the stern structure of a high-speed ship such that a wing running condition is formed.
It is suitable for hydrofoil vessels that run at low speeds and wing at high speeds, and actively promotes buoyancy or lift to the stern of the boat to assist a smooth transition (takeoff) from boat running to wing running. Additional protrusions (hereinafter referred to as "trim suppression device")
To a "take-off assisting device").

[0002]

2. Description of the Related Art In a high-speed ship such as a planing boat or hydrofoil, the bow rises at high speed, while the stern tries to sink deeper into the water, that is, trim. It is extremely important for the propulsive performance of this type of high-speed ship to be able to quickly get out of the hump state and shift to the planing state or the wing running state (takeoff).

By the way, the above-mentioned phenomenon becomes more remarkable as the boat speed increases, which causes an increase in trim. If the trim exceeds a certain level, propulsive resistance increases and the engine stalls, as well as problems such as poor needle holding performance occur. In order to avoid this, it is necessary to prevent the trim from becoming excessive even if the boat speed increases, but the following two methods have been conventionally known, roughly classified.

In order to prevent the bow from rising,
Move the center of gravity to the bow side.

Although this method is simple and effective, the position of the center of gravity cannot be adjusted in many cases due to the arrangement inside the ship. Also, especially in hydrofoil vessels, it is common to set the center of gravity and set the wing based on the wing running condition (the main hull is completely levitated). It is not realistic because it is difficult to put in the position.

As described above, since it is actually difficult to adjust the position of the center of gravity, as shown in FIG. 10, a stern end 21 is provided with a plate-like trim tab 22 so as to project (for example, Japanese Utility Model Publication 58-440).
(See No. 77, No. 4-62297, No. 4-62299)
Alternatively, as shown in FIG. 11, a step 26 is formed on the bottom 25 of the ship.
A so-called step ship type is provided (for example, JP-A-54-95491, JP-A-54-126388, and JP-A-61-12939).
No. 0, refer to JP-A-4-334693). The trim tab and the step hull form are intended to lift the hull in a balanced manner by generating a levitation force at the stern, suppress trim at the time of high speed transition, and quickly get out of the hump state.

[0007]

[Problems to be Solved by the Invention] When Conventional Trim Tabs are Adopted All of the conventional trim tabs project backward from the stern end and are made movable by the drive mechanism 23 to control the angle of attack. Therefore, due to its structure, the obtained lift is small, and therefore it can be applied to small high-speed ships such as motor boats, but larger passenger ships (hydrofoil).
Even if it is applied as it is, no great effect can be expected.

Most of the conventional trim tabs are tabular and mainly have lift, and few expect buoyancy at the same time. However, when it comes to high-speed passenger ships, buoyancy is often required as well as lift in order to quickly transition to a gliding state or a wing running state. Therefore, there is a need for a universally applicable boat, from small boats such as motor boats to large high-speed boats. Also, if it is movable,
It is desirable that the device be as simple as possible because its mechanism becomes complicated and the number of incidental equipment increases.

In the case of adopting the conventional step ship type Since the bottom of the ship is formed in a step shape, the hull structure itself becomes very complicated and its design and manufacture becomes much more difficult than usual. In addition, the internal structure of the hull becomes complicated, which may hinder the arrangement of devices. The center of gravity of the ship is preferably slightly trim trim stern in terms of propulsion performance during traveling, but when a step ship type is adopted, propulsion equipment is often mounted in the ship in front of the step section (for example, Japanese Patent Laid-Open No. Therefore, the center of gravity of the entire ship cannot be set to the optimum position in many cases. It is an object of the present invention to prevent the trim from becoming excessive by additionally (assistingly) generating buoyancy or lift on the trim suppressing projection provided integrally with the stern at the bottom of the stern for propulsion. (EN) It is an object to provide a trim suppressing device for a high-speed ship, which makes it easy to reduce the resistance and maintain the needle holding property.

[0010]

In order to achieve the above object, a trim suppressing device for a high-speed ship according to the first invention (claim 1) comprises:
In the stern part of a high-speed ship that forms a gliding state or a wing-running state in the high-speed range, a protrusion extending symmetrically from near the hull centerline to the port side is provided on the bottom of the stern, and the shape of the protrusion is It is characterized in that it is formed in a wedge shape that inclines downward toward the stern.

A trim restraint device for a high-speed ship according to a second aspect of the present invention (claim 2) is a stern part of a high-speed ship that forms a gliding state or a wing-running state in a high-speed range, on both sides of the bottom of the stern part. A projection extending from a position a certain distance from the center line of the hull to the port side and a certain distance in front of the stern end, and the shape of the projection is formed in a wedge shape that inclines downward toward the stern. To do.

A trim restraint device for a high-speed ship according to a third aspect of the present invention (claim 3) is a stern part of a high-speed ship that forms a gliding state or a wing-running state in a high-speed range, and both sides of the bottom of the stern part. A projection extending from a position a certain distance from the hull centerline to the port side and its rear end extending to the stern end position, and the projection is formed in a wedge shape that inclines downward toward the stern. To do.

A trim suppressing device for a high-speed ship according to a fourth aspect of the present invention (claim 4) is a stern part of a high-speed ship that forms a gliding state or a wing-running state in a high-speed range, with the hull center at the bottom of the stern part. A first protrusion that symmetrically extends from the vicinity of the line to the port side is provided, and the shape of this first protrusion is formed into a wedge shape that inclines downward toward the stern, and at the bottom of the stern part that is continuous with the first protrusion. On both sides of the ship, a second projection that extends from a position a certain distance from the center line of the hull to the side of the ship and a certain distance toward the stern end is connected, and the shape of this second projection is lowered toward the stern. It is characterized in that it is formed in an inclined wedge shape.

[0014]

The lift-type trim suppressing device is formed by the protrusion of the first invention. That is, the stern has a shape with a gradient with respect to the flow at the bottom of the stern, and a lift force commensurate with the levitation force acting on the bow is generated on the protrusion provided on the stern, and the bow and stern are levitated in a balanced manner, and the trim suppression action is performed. That is, the attitude control action of the hull is exerted, and as a result, it is possible to quickly shift from the hump state to the gliding or wing running state with a small horsepower (thrust).

The protrusions of the second invention form a trim suppressing device for both lift and buoyancy. That is, similarly to the first aspect of the invention, a lift is generated by giving a slope to the bottom of the stern, but a large lift cannot be expected when the ship speed is slow.
Therefore, a shape that doubles as a buoyant body is used so that buoyancy acts instead of lift at low speeds, and the trim suppressing effect is exhibited not only at high speeds but also at low speeds.

The protrusion suppressing member of the third aspect of the invention also forms a trim suppressing device for both lift and buoyancy. That is, the action is similar to that of the second invention, but it is preferable to apply the present invention to a ship in which it is advantageous to obtain particularly large buoyancy.

The first projection body and the second projection body of the fourth invention form a composite trim suppressing device having the functions of the first invention and the second invention. That is, the lift type of the first protrusion exerts a trim suppressing effect at high speed, and the lift / buoyancy type of the second protrusion also works at high speed, but rather, it is an effective trim at low speed. Exerts an inhibitory effect.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The present invention is intended for a high-speed ship that forms a gliding state or a winging state in a high-speed range, but in the following, for convenience, a hydrofoil ship shown in FIG. 1 which is particularly suitable for the present invention will be described as an example. FIG. 1 is a so-called composite support type hydrofoil.

The hydrofoil of FIG. 1 has a torpedo-shaped submersible body (floating body) 4 provided below the upper hull 1 through struts 2 and runs at draft WL ₁ in the low speed range, a so-called boat running state. In the high speed range, there is a wing running state in which the upper hull is floated by the buoyancy of the submerged body 4 and the lift generated by the hydrofoil 3 to travel.

This hydrofoil requires a large propulsive force at the time of take-off when the running state is changed to the wing state.
At high speeds, the bow rises, the stern sinks, and the trim increases, causing propulsion resistance to increase. Therefore, take-off (planing state for planing boats) occurs.
Is often difficult.

Therefore, among the high-speed boats to which the present invention is applied, one of the following three types is adopted in order to facilitate the smooth transition to the planing state for planing boats and the take-off assistance for the above hydrofoil boats. A trim suppression device is provided on the stern.

Lift-type trim restraint device A (see FIG. 2) This is a wedge-shaped trim restraint device A (take-off in the hydrofoil of FIG. 1) that symmetrically extends from the vicinity of the hull centerline 5 on the stern bottom surface 7 to the port side. It is also called an assisting device). FIG. 2 is a perspective view of the bottom of the stern, and a rectangular recess 8 is formed on the bottom 7 of the stern so as not to interfere with the jet jet discharge area. The recess 8 is formed by a lateral wall 8a extending in the port side direction and a vertical wall 8b on both sides extending to the stern end 9. The lateral wall 8a is provided with a discharge nozzle 6 of a water jet propeller (not shown).

The protrusion a forming the lift-type trim suppressing device A has a wedge shape protruding downward on the stern bottom surface 7, that is, a substantially straight line toward the stern when viewed in a longitudinal section cut in the longitudinal direction of the ship. It is formed in a wedge shape that inclines downward,
The position of the lateral wall 8a is extended to the port side with the rear end as the rear end.
The protrusion a may be formed by adding a protrusion to the bottom of the ship, or the bottom of the ship itself may be formed as a part of the hull from the beginning in the shape of the protrusion a. Good. This also applies to the trim suppressing device described below. The details of the lift type trim suppressing device A are almost the same as those in FIGS. 8 to 9 described later.

As shown in FIG. 3, in the case of this lift-type trim restraint device A, since it has a shape having a gradient with respect to the flow S at the bottom of the stern, the levitation force L acting on the bow portion at high speed traveling is obtained. _The hull can be levitated while maintaining the equilibrium state (that is, without causing excessive trim) by generating _a lift force La corresponding to _f at the stern portion. As a result, an increase in resistance at the time of take-off is suppressed, so that it is possible to smoothly transition to the wing running state with a small horsepower (thrust). In this sense, the trim suppressing device can also be called a take-off assisting device.

Lift and buoyancy type trim suppressing devices B, B ₁ (see FIG. 4) In the example of FIG. 4 (a), there is a rectangular recess 8 for a jet jet, and the recess 8 is A wedge-shaped trim suppressing device B having a vertical cross section (a cross section when cut in the longitudinal direction of the ship) is inclined substantially linearly downward toward the stern is provided on both sides of the sandwich.

A protrusion b forming the trim suppressing device B
In the case of, the rear end does not extend to the stern end 9 but to a certain distance before the stern end 9, that is, in this example, to the vicinity of the start point of the corner R of the corner of the stern end 9. is there. The details of the trim suppressing device B in this case are almost the same as those in FIGS.

The example of FIG. 4 (b) is an example in which the protrusion b ₁ of the trim suppressing device B ₁ is extended to the position of the stern end 9. The plane shape near the stern end 9 of the protrusion b ₁ is the same as the stern shape. That is, it has the same R as the corner radius R (FIG. 4 (a)) at the corner of the stern end 9.

As shown in FIG. 5, in the case of the dual type trim suppressing device B as well as in the case of the lift type described above, the lift L _a is generated by giving _a gradient to the flow S at the bottom of the stern. Large lift cannot be expected when the ship speed is slow. Accordingly, low speed has a lift alternative (although some lift Occurring) the shape which also serves as a buoyant body to work buoyancy B _a. That is, the levitation force (L _a + B _a ) commensurate with the levitation force L _f of the bow is generated in the stern to suppress the trim so that the takeoff in the case of a hydrofoil can be performed smoothly and quickly. There is.

Composite trim suppressing device C (see FIG. 6) This is a trim suppressing device C in which a lift suppressing and buoyancy combining type trim suppressing device B with the lift type trim suppressing device A described above are combined. That is, the trim suppression device C
Is composed of a lift type trim suppressing device A extending along the lateral wall 8a to the port side, and a dual type trim suppressing device B provided so as to be continuous with the lift type trim suppressing device A.

The composite trim suppressing device C is characterized in that it exerts its effect over the entire range from low speed to high speed.
In other words, the lift type exerts its effect by generating lift at high speeds, and the dual type exerts its effect at low speeds rather. This is because the water surface S ₁ at the time of low speed is above the trim suppressing device B and generates buoyancy and lift. However, as shown in FIG. 7, at the time of high speed, the water surface S ₂ near the stern is extremely lowered and the buoyancy and lift are increased. Because it is hard to occur.

The structure of the composite trim suppressing device C will be described in detail below with reference to FIGS. 8 and 9. FIG. 8 is a plan view of the stern bottom, showing a lift-type trim suppressing device A that has a rear end at the same position as the lateral wall 8a of the recess 8 and has a wedge cross section that is inclined forward and extends from around the hull centerline 5 to the port side. One projection a has a recess 8
The second protrusion b related to the dual-purpose trim suppressing device B extending from the position of the vertical wall 8b to the port side 7a is continuously provided. The rear end b ₀ of this second protrusion b extends to a certain distance before the stern end 9, that is, to a position near the starting point of the corner radius R of the corner of the stern end 9.

9A, 9B and 9C are a sectional view taken along the line XX, a sectional view taken along the line YY and a side view in FIG. 8, respectively. All show only the port side.

The lift-type trim suppressing device A has a hull center line 5
From the vicinity, passing through the knuckle line KL and from the bottom surface of the ship to a substantially constant wedge shape, that is, as shown in FIG. 9 (c), a wedge-shaped (triangle) -shaped first slanted downward toward the stern in a side view. The projection a is formed by extending to the port side 7a. Further, a projection b related to the dual-purpose trim suppressing device B having a wedge-shaped side cross section which is continuous with the rear end surface a ₀ of the first projection a and inclines downward substantially linearly toward the stern is provided. There is. As shown in FIG. 9 (a), at the rear end a ₀ position of the lift-type first protrusion a, there is a slight step between the lift-type first protrusion a and the dual-purpose second protrusion b, but it gradually increases toward the port side 7a. This step becomes smaller, and both are in agreement at the port side 7a position. Therefore, as shown in FIG. 9 (c), at the position of the port side 7a, the side cross-sections of both sides have a wedge (triangle) shape.

[0034]

In the invention according to claims 1 to 4, the trim suppressing projection is integrally or additionally formed on the bottom surface of the stern ship, so that the bow and the stern are levitated in a balanced manner in the high speed range. Can be controlled to obtain a trim suppression effect. As a result, it becomes possible to smoothly and quickly shift from the hump state to the gliding state or the wing running state with a small horsepower (thrust).

By additionally and assistingly generating a buoyant force or a lift force at the time of take-off that requires the most thrust, it is possible to reduce the propulsion resistance by suppressing the trim and to maintain the needle holding property.

Further, since the trim suppressing device of the present invention can be additionally provided on the bottom surface of the stern, in that case, the trim suppressing device can be implemented without complicating the hull structure itself.
It can be easily applied to existing ships.

In the invention according to claim 1, a lift-type trim suppressing device is formed, and particularly when the trim suppressing effect is required at a high speed, this simple device may be used.

According to the second and third aspects of the present invention, the lift suppressing and buoyancy type trim suppressing device is formed, and in particular, since the buoyant force can act instead of the lift force at a low speed, the take-off at a relatively low ship speed can be performed. This is advantageous in the case of a hydrofoil that requires The invention according to claim 3 may be applied to a ship that requires particularly large buoyancy.

In the invention according to claim 4, a composite type trim suppressing device having the functions of both a lift type and a combined type is formed, and an effective trim suppressing effect is exhibited regardless of low speed and high speed, and smooth In addition, quick take-off and the like can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view of a composite support type hydrofoil, which is an application example of the present invention.

FIG. 2 is a perspective view of a stern bottom provided with a lift type trim suppressing device of the present invention.

FIG. 3 is a diagram showing the same operation.

4 (a) and 4 (b) are perspective views of a stern ship bottom equipped with two different lift and buoyancy type trim suppression devices according to the present invention.

FIG. 5 is a diagram showing the same operation.

FIG. 6 is a perspective view of the stern bottom of the ship equipped with the composite trim suppressing device according to the present invention.

FIG. 7 is a diagram showing the same operation.

FIG. 8 is a plan view of the stern bottom of the stern showing details of the composite trim suppressing device.

9A to 9C are a cross-sectional view taken along the line XX, a cross-sectional view taken along the line YY, and a side view of FIG. 8, respectively.

FIG. 10 is a side cross-section of a conventional trim tab.

FIG. 11 is a side view showing a conventional step boat type.

[Explanation of symbols]

 A ... Lift type trim restraint device B ... Lift and buoyancy type trim restrainer C ... Composite trim restrainer a ... (First) protrusion b ... (Second) protrusion 1 ... (Upper) hull 2 ... Strut 3 ... Hydrofoil 4 ... Submerged body 5 ... Hull center line 6 ... Discharge nozzle 7 ... Stern bottom 7a ... Port side 8 ... Recess 8a ... Side wall 8b ... Vertical wall 9 ... Stern end

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakazu Tomita 3-1-1 Higashikawasaki-cho, Chuo-ku, Kobe-shi, Hyogo Kawasaki Heavy Industries Ltd. Kobe factory

Claims (4)

[Claims] 1. In a stern part of a high-speed ship that forms a gliding state or a wing-running state in a high-speed range, a protrusion extending symmetrically from near the center line of the hull to the port side is provided on the bottom of the stern, and the protrusion is formed. A trim suppressing device for a high-speed ship, wherein the body is formed in a wedge shape that inclines downward toward the stern. 2. In the stern part of a high-speed ship that forms a gliding state or a wing-running state in a high speed range, the stern extends from a position a certain distance from the center line of the hull to the port side on both sides of the bottom of the stern part. A trim suppressing device for a high-speed ship, characterized in that a protrusion extending to a certain distance in front of the end is provided, and the shape of the protrusion is formed in a wedge shape that inclines downward toward the stern. 3. A stern of a high-speed ship that forms a gliding state or a wing-running state in a high-speed range, extends from a position a certain distance from the center line of the hull to the port side on both sides of the bottom of the stern, and then A trim suppressing device for a high-speed ship, characterized in that a projecting body whose end extends to a stern end position is provided, and the projecting body is formed in a wedge shape that is inclined downward toward the stern. 4. A stern portion of a high-speed ship that forms a gliding state or a wing-running state in a high-speed region, and a first protrusion that symmetrically extends from near the center line of the hull to the port side is provided on the bottom of the stern portion, The shape of this first protrusion is formed in a wedge shape that inclines downward toward the stern, and is continuous from the first protrusion to both sides of the ship bottom of the stern from the position a certain distance from the hull centerline to the port side. Trim control of a high-speed ship, characterized in that a second protrusion extending continuously and extending to a stern end up to a certain distance is continuously provided, and the shape of the second protrusion is formed in a wedge shape that inclines downward toward the stern. apparatus.