JP3247970B2 - Hull structure of a trimaran - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a hull structure of an integrally formed trimaran having two smoothly formed air introducing tunnels.

[0002]

2. Description of the Related Art The technology relating to a trimaran is already known. For example, as disclosed in JP-A-49-28091. The prior art trimaran described in FIG.
As shown in FIGS. 11 and 12, a hull form has three hulls connected in a horizontal direction and has three peaks and two valleys at the bottom of the hull. Side hulls 3 'and 3' and a center hull 1 'are formed. These side hulls 3 'and 3'
As shown in FIG. 10, air is taken into the valley of the center hull 1 'and serves as a cushion to reduce the impact.
In addition, when navigating, air flow is created on the underside of the fuselage, so the drafting part is the side hull 3 '
There are only three points, the front part of 3 'and the rear part of center hull 1', and there is little water contact. Therefore, the air cushion effect is also limited in the valley and there is a problem that there is a limit.

In general, other conventional trimarans (trimarans) also have better lateral strength and a better inner capacity than catamaran-type hulls because they have more water contact between the hulls (connection parts). Is also big. However, on the other hand, there was a problem that the hull resistance was large due to the large water contact area.

[0004]

SUMMARY OF THE INVENTION The present invention provides a hull structure in which the hull resistance is reduced and the air cushion effect is further improved without impairing the advantages of the trimaran.

[0005]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. In claim 1, the front part of the ship bottom
Left and right side hull 3.3 and center
Center hull with a center hull 1
Left and right of the center hull 1 at the front
And the left and right surrounding walls 12 and 12 and the center hull 1 in the center.
Thus, a closed "U" -shaped concave portion 8b is formed.

According to the second aspect of the present invention, the front to rear portions of the ship bottom are provided.
Of the left and right side hulls 3.3 and the center
On a trihull equipped with a tar hull 1,
A pair of strips on the left and right sides of the
Protruding strips 9.9, the spacing between the strips 9.9
Is the diameter of the propeller 14 at the position of the transom 6 at the stern end.
Open gradually so that the position is at least twice as wide
It is a thing.

[0007]

Next, an embodiment of the present invention will be described. At the bow, the left and right side hulls 3.3 provided on the side surface and the center hull 1 at the center are connected by a large curved surface. And the tunnel part 7 formed smoothly also in the front-back direction of a hull is formed. By forming the tunnel 7 in the longitudinal direction of the hull, air is introduced into the bottom of the hull. The reason why the tunnel 7 is divided into right and left is to allow air to flow into the ship bottom as uniformly as possible.

The keel portion 2 of the bow side center hull 1a is
It is located above the running waterline 11 and, conversely, below the stationary waterline 10. By arranging the position of the keel portion 2 of the bow-side center hull 1a in this manner, the hull portion 2 of the bow-side center hull 1a does not come into contact with water during normal running, so that no hull resistance is generated. Since the keel portion 2 of the bow side center hull 1a also comes in contact with water, it plays a role of preventing sinking of the bow portion and reducing impact. In addition, when stationary, the keel portion 2 of the bow side center hull 1a comes in contact with water, so that the stability is further improved.

[0009] 30 to 35% of the total length measured from the bow side
Is provided with a step 5 having an appropriate height reaching the vicinity of the keel 4 of the side hull 3, and the step 5 is used as a front surrounding wall. The intersection between a line parallel to the center line of the hull and the transom 6 at the stern end, which passes through both ends of the step 5, and the surface formed by the upper and lower ends of the step 5 is defined as a side surrounding wall 12. A recess 8b is formed in a space surrounded by the step 5 and the three surfaces of the left and right surrounding walls 12 and the water surface,
In the recess 8b, there is always an air layer through which air pressure is applied by the forward speed of the hull through the tunnel portion 7.

The position of the step 5 is set at 30 to 30
The reason for limiting the range to 35% is that if the step 5 is located behind the step, more water concentrates in the concave portion 8a of the three hull valleys ahead of the step 5 while surfing the waves,
This causes a problem that the ship speed is reduced every time the vehicle enters the wave. In addition, there is no space for producing the air cushion effect in a range where the maximum wave impact water pressure is frequently generated.

Conversely, if the step 5 is located in front of this, the surrounding wall of the front rises, and the air accumulated at the bottom of the ship escapes forward when a wave shock occurs, and acts due to the step 5 and the recess. This reduces the effect of the air cushion. The height of the transom valley 13 is set to a height in contact with the water surface at the time of the run, that is, the same height as the waterline at the time of the run.
As a result, the air at the bottom of the hull is discharged during normal running, and the hull sinks when receiving a wave impact, thereby exhibiting the effect of storing the air at the bottom of the hull.

The keel 4 of the side hull 3 is gradually lowered forward toward the bow, and the lowermost end is near the step position. From the lowermost position, it rises sharply. This has the effect of making the air layer thicker near the steps. Stern side center hull 1
b is configured to intersect with the traveling waterline 11 near the middle of the step 5 and the transom 6. As a result, the air in the bottom of the ship is again divided into right and left, and is discharged from the valley 13 of the transom 6 at the stern end. Further, a pair of left and right strips 9 and 9 are provided at a position on the transom 6 at the stern end that is at least twice as wide as the diameter of the propeller 14. The pair of left and right strips 9 reduces the width of the flat portion as approaching the step 5.

This prevents the air collected in the recess 8b formed by the step 5 and the surrounding wall 12 from entering the propeller 14, and changes the direction of the spray generated by the stern-side center hull 1b, so that the spray moves to the recess 8b. It prevents an increase in the hull resistance caused by entering or hitting the side hulls 3. As approaching the step 5, the strip 9
The reason why the width of 9 is reduced is that the impact is greater on a surface that is closer to the horizontal, and the area thereof is minimized.

The operation will be described. Air is introduced into the bottom of the hull through the tunnel 7 at the bow by the pressure based on the hull forward speed. Through the step 5, the step 5 at the bottom of the ship
The entire recessed portion 8b formed by the surrounding wall 12 is filled with the air. A pressured air layer always exists in the bottom recess 8b. When traveling on a calm surface, the presence of the air layer causes the water contact area at the bottom of the ship to be much smaller than that of a conventional trihull, thereby reducing the hull resistance. On the other hand, when traveling in waves, when the hull sinks and receives a wave impact on the bottom of the ship, the air layer plays a role of a cushioning material to reduce the impact.

[0015]

As described above, the present invention has the following advantages. Of As, the ship's bottom as claimed in claim 1,
Right and left side hulls 3.3, from front to back
And the center hull 1
Left and right of the center hull 1 in the center of the
5.5, left and right surrounding walls 12 and 12 and center hull in the center
1, the closed "U" -shaped concave portions 8b are formed.
As a result, an air layer can be made to exist at the bottom of the ship by the concave portion 8b, and the air layer can improve the buffering effect of wave shock during navigation. Further, the hull resistance can be reduced and the air cushion effect can be further improved without impairing the advantages of the trimaran. In particular, 3
This is effective for high-speed ships around 0 knots. Furthermore, unlike a catamaran, it is not necessary to have a sufficient head-to-body height so that the water surface does not come in contact with the bottom of the boat even in the waves, so the combined rigidity of the shape and the lateral strength at the same weight as a monohull Can be secured. Since the bottom of the hull is very small in comparison with the catamaran hull form, the inside capacity of the hull can be increased, and the height of the dwelling part can be kept low.

[0016] According to a second aspect of the present invention, the whole of the front part to the rear part of the ship bottom is provided.
The left and right side hulls 3.3 and the center center
The center hull 1 at the bottom of a trimaran with hull 1
A pair of strips on the left and right sides from front to back
Projecting a 9.9, the spacing between the strip 9, 9, the ship
More than twice the diameter of the propeller 14 at the position of the tail end transom 6
, So that the air gathered in the recess 8b formed by the stepped step 5 and the surrounding wall 12 is prevented from entering the propeller 14, and the stern is formed. The direction of the spray generated by the side hull 1b is changed so that the spray enters the recess 8b,
Thus, it is possible to prevent the hull resistance from increasing in the case of No. 3. In addition, as the width of the strips 9.9 is reduced as approaching the step 5, the impact of the water surface on the strips 9.9 is greater on a surface that is closer to the horizontal, and the area of the strip 9.9 is minimized. The impact due to the collision can be avoided.

[Brief description of the drawings]

FIG. 1 is an overall side view of a trimaran according to the present invention.

FIG. 2 is a side view of the hull of the trimaran according to the present invention.

FIG. 3 is a bottom view showing the bottom of the trimaran of the present invention.

FIG. 4 is a front view of the trimaran according to the present invention.

FIG. 5 is a rear view of the trimaran according to the present invention.

FIG. 6 is a drawing showing a draft portion at the time of rest of the bottom of the trimaran according to the present invention.

FIG. 7 is a side view showing the flow of air to the hull.

FIG. 8 is a bottom view showing the position of a waterline during navigation.

9A and 9B are a front view and a rear view showing a draft state of the tripod of the present invention at rest.

FIG. 10 is a side view showing the air flow of a conventional trimaran.

FIG. 11 is a bottom view showing a draft surface during navigation of a conventional trimaran.

FIG. 12 is a front view and a rear view showing a waterline when a conventional trimaran sails.

[Explanation of symbols]

 1 Center Hull 2 Keel of Center Hull 3 Side Hull 4 Keel of Side Hull 5 Step Step 6 Stern End Transom 7 Tunnel 9 Strip 10 Stationary Waterline 11 Running Waterline

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-92285 (JP, A) JP-A-2-503895 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B63B 1/12 B63B 1/32

Claims (2)

(57) [Claims] 1. From the front part to the rear part of the bottom of the ship,
Right side hull 3.3 and center hull 1 in the center
Left and right of the center hull 1 in the center of the bottom of a trimaran
In addition, the front step step 5.5 and the left and right surrounding walls 12
And closed by the central hull 1
The hull structure of a trimaran, wherein the hulls are formed with concave portions 8b . 2. From the front to the rear of the bottom of the ship,
Right side hull 3.3 and center hull 1 in the center
In the trimaran, on the left and right sides of the center hull 1 at the bottom of the ship,
Projecting a pair of strips 9.9 from front to back
The spacing between the strips 9
At a position at least twice the diameter of the propeller 14 at the position of the
The hull structure of a trimaran, characterized in that it is gradually opened .