JP2547300Y2 - Hull Damage Prevention Device for Hydrofoil Ship - Google Patents

Description

[Detailed description of the invention]

[0001]

[Industrial application] This invention is based on
The present invention relates to a hull damage preventing device for a hydrofoil marine vessel, which is provided with directionality in a separating direction even when a large floating substance hits a strut on a bow side so as not to damage the hull.

[0002]

2. Description of the Related Art In order to respond to recent needs for speeding up cargo and passenger transportation, hydrofoil vessels as shown in FIG. 4 have appeared on domestic routes. This hull form is called a so-called submerged wing type hydrofoil boat, and the bow and stern of the upper hull 1
It has struts 2 that hang down from the bottom of the ship. The hydrofoil sails on the WL ₁ draft line during low-speed navigation (this is referred to as “boat running”), and during high-speed navigation, the hydrofoil 3 lifts the upper hull 1 to a position where the draft line becomes WL _2. It rises and sails (this state is called "wing running"). The propulsion is by water jet propulsion.

[0003] While a hydrofoil boat is running in a wing running state of the draft line WL ₂ as shown in FIG. 4, a large floating substance G on the sea is rapidly applied to a bow-side strut (hereinafter also referred to as a “bow strut”) 2. Because of that, there are times when you can not avoid collision. In preparation for this, a shock absorber 4 which is a mechanical shock absorbing mechanism as shown in FIG. That is, as shown in FIG. 5, the bow strut 2 is supported on the hull H side via the support member 5 having a V shape in a side view. Actually, a pair of the support members 5 are provided on the left and right sides so as to sandwich the yoke 2A on the upper part of the strut 2. The upper part of the strut 2 is rotatably supported on the support member 5 around the support shaft 6, and the lower end of each support member 6 is mounted on the hull H
The support member 6 is pivotally supported by a support pin 7 on a triangular bracket Ha protruding therefrom, and the support member 6 is supported by a shock absorber 4 formed in a stepped cylindrical shape. Therefore, the strut 2 is rotatable around the support shaft 6 in the same plane as the paper, and can be flipped counterclockwise by the extension of the actuator 8 connected to the upper end of the yoke 2A.

The stepped outer cylinder 4a of the shock absorber 4
Is fitted with an inner cylinder 5a having the same shape, and the front end of the inner cylinder is connected to the support member 5 by a pin 5b.

Therefore, when the floating material G hits the strut 2, a force in the bow direction acts on the support member 5 via the support shaft 6, so that the V-shaped support member 5 is supported by the support pin 7 at the lower end.
Is moved in the bow direction with the fulcrum as a fulcrum, and the inner cylinder 5a operates so as to come off from the outer cylinder 4a of the shock absorber 4.
Since “a” is reduced in diameter from the stepped portion, a resistance force that prevents the inner cylinder 5 a from coming off occurs here. This works as a shock absorbing effect.

[0006]

In the vicinity where the shock absorber 4 is provided, there are a mechanism for flipping the strut 2 up and a mechanism (not shown) for rotating the strut 2 around the axis for steering. At the present time, it is a structurally complicated part, and furthermore, since the shock absorbers 4 need to be provided on each support member 5, the hull structure and the mechanism are extremely complicated at present.

The shock absorber 4 is designed to absorb an impact force within a certain range, as is apparent from the configuration itself. However, if the shock force exceeds the range, the shock absorber 4 is protected to protect the hull. Is configured such that the inner cylinder 5a comes off from the outer cylinder 4a. In such a case, the U-shaped support member 4 is changed from two-point support to one-point support at the lower end, and the hydrofoil that landed at the moment of hitting a floating object or the like is still in the forward state due to inertia. Therefore, the strut 2 swings right behind and hits the bottom of the ship, thereby damaging it. If the hull is damaged, it must be docked for a long period of time for repairs, during which time it will not be able to operate, resulting in large losses. In this way, despite the provision of shock absorbers to protect the hull, there is an inconvenience that hull damage is inevitable in the event of a collision with a large suspended object.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a hull damage preventing device which can effectively prevent hull damage by providing directionality in a strut separation direction without providing a shock absorber. To provide.

[0009]

According to the present invention, a bow strut of a hydrofoil is divided into flanges near the root of the hull, and the flange surface is inclined backward and downward by a predetermined angle from a horizontal line. A hull damage prevention device for a hydrofoil ship having a fastening bolt with a strength difference between the left and right among a plurality of fastening bolts disposed on the left and right flange portions with the strut interposed therebetween, and a bow strut for the hydrofoil ship. Divide the flange near the root of the hull, and incline this flange surface backward and downward by a predetermined angle from the horizontal line , and
The left and right flange surfaces across the strut are from the right side of the hull to the left
This is a hull damage prevention device for a hydrofoil ship inclined to the side . Further, in the above configuration, an inflatable air bag is provided in the strut below the flange joint.

[0010]

[Action] When a hydrofoil wing is winging and a bow strut hits a large floating object (at this time, the hydrofoil lands), if the impact force exceeds a certain range, the strut will protect the hull. Therefore, it is separated from the flange joint position. In this case, since the flange is inclined, not only the shearing force but also the bending is applied to the fastening bolt, and further, the fastening bolt is cut from a weak bolt among the plurality of fastening bolts. Once the weak bolt is cut, the other bolts are cut one after another in a chain, and then the strut has directionality because the first cut part is biased by fluid force etc. ) Be separated. The separated lower strut will try to submerge in the water without hitting the hull, but if the strut is equipped with an inflatable air bag, it will automatically inflate and generate buoyancy, causing the strut to rise to the sea. Float to facilitate recovery.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a structural view showing an attachment relationship between a bow strut 2 and a hull H according to an embodiment of the present invention. The strut 2 is vertically divided into two near the root of the hull H from the flange joint 9. The upper and lower flanges constituting the flange joint 9 are connected by a plurality of fastening bolts 10. A yoke 2A is attached to the upper strut 2, and the yoke 2A is connected at its upper end to an actuator 8 for flipping up. The yoke 2A is supported by the hull bracket Ha via the support shaft 6, whereby the strut 2 is supported on the hull H side. Although a steering mechanism for rotating the strut 2 about the axis is also provided, it is omitted in the figure for simplicity. When the boat is stopped, the strut 2 can be pivoted counterclockwise around the support shaft 6 by extending the actuator 8 so that the strut 2 can be flipped up. At the time of sailing, the actuator 8 is shortened to a position hanging down from the ship bottom as shown in the figure.
Becomes faster, the lift generated on hydrofoils 3 struts 2 lower floated upper hull 1 to the position of the water line WL ₂ wings run by.

As shown in FIG. 1, the flange joint 9 is provided to be inclined rearward and downward. That is, it is inclined rearward and downward by θ from the horizontal line. The reason why the flange 9 is provided so as to be inclined is that not only the shearing force but also the bending moment is applied to each of the fastening bolts 10 when the floating material G collides with the strut 2 and the impact force F is applied. This is because, in this case, it is easy to give directionality to the strut 2 in the separating direction as described later. If the flange is provided horizontally, only the shearing force acts on each fastening bolt, and the entire fastening bolt opposes this, so that it is difficult to give directionality in the separating direction. FIG. 2 is a plan view of the flange 9.
A plurality of fastening bolts 10 are annularly intermittently provided on a flange 9 provided on the strut 2 having a streamlined cross section. The height at which the flange 9 is provided is set so as not to hit the rising waves during wing running so as not to increase the hull resistance during wing running.

The bow strut 2 incorporates the hull damage preventing function of the present invention. That is, the strut 2
When receiving a large impact force F exceeding a certain range, the fastening bolt 10 is cut and can be separated from the flange dividing position.

The degree of impact when the strut is to be cut off is determined from the viewpoint of hull protection. In the present invention, the strut is devised so as to be displaced to the left or right so that it does not hit the hull by swinging right behind as in the conventional case. As a means for giving directionality to the separation as described above, there is the following method.

It is to keep some of the large number of fastening bolts 10 weaker than others. For example, the group of the fastening bolts 10a on the left is made weaker in strength than the one on the right. Moreover, it is preferable that the bow bolt of the left fastening bolt 10a is weakened. This is because the greatest bending is applied here to make it easy to have a separating direction. The strength of the fastening bolt can be easily achieved by changing the diameter of the bolt or changing the material.

In the above example, when the shear stress or the bending stress resulting from the impact force exceeds the tensile strength of the fastening bolt, it is broken. In this case, the weak fastening bolt 10a on the left side is broken first. Then, this causes the fastening bolts 10a on the same side to break in a chain. At the moment when the hydrofoil comes into contact with a floating object or the like, the hydrofoil comes into contact with the water. Therefore, the strut 2 does not collide with or damage the hull.

FIG. 3 shows another embodiment (side view of the flange portion).
In this figure, the flange 9 is inclined backward and downward, and the right flange portion 9a is lower than the left. That is, the flanges are inclined at the front, rear, left and right. By doing so, the magnitude of the shearing force or bending moment acting on the fastening bolt due to the impact force can be made different from side to side. In this case, even if the same fastening bolt is used, the above-mentioned left and right fastening bolt group The same effect as in the case where the strength is added to the strength can be obtained.

The strut 2, which has been deflected so as not to hit the hull as described above, is immersed in the water as it is. However, it is difficult to recover the strut 2 where the water depth is large. Therefore, in order to facilitate this recovery, it is desirable to equip the inflatable air bag 11 in the strut 2 immediately below the flange joint 9 as shown in FIG. Then, even if the strut 2 is cut off, the airbag 11 is automatically inflated to generate buoyancy, so that the strut 2 can be floated on the sea, which facilitates the collection.

[0019]

[Effects of the Invention] Even if a large floating object hits the bow strut, the bow strut is deflected and separated from the inclined flange portion by the impact, so that the risk of damaging the hull by the strut is drastically reduced. Further, the strut can be separated in a predetermined direction depending on the inclination direction of the flange and the strength of the fastening bolt, that is, it is possible to have directionality in the separating direction, so that hull damage is effectively and reliably avoided. Can be. There is no need to provide a structurally complicated mechanism such as a shock absorber, and the hull structure becomes simple. When the inflatable air bag is provided, even if the strut is broken, the strut floats, so that the collection becomes easy.

[Brief description of the drawings]

FIG. 1 is a side view of a main part showing a strut structure showing an embodiment of a hull damage mechanism of the present invention.

FIG. 2 is a plan view of a flange portion.

FIG. 3 is a side view of a flange portion according to another embodiment.

FIG. 4 is a side view showing an example of a hydrofoil ship in a running state to which the present invention is applied.

FIG. 5 is a side view of a main part showing a mounting relationship between a bow strut with a conventional shock absorber and a hull.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Upper hull 2 ... Strut 3 ... Hydrofoil 9 ... Flange (joint) 10 ... Fastening bolt 11 ... Airbag G ... Floating material H ... Hull

Claims (3)

(57) [Scope of request for utility model registration] 1. A bow struts in hydrofoils and flanges divided around the hull base, yet the flange surface
It is inclined backward and downward by a predetermined angle from the horizontal line and
On the left and right flanges across the strut
Fastening bolt with strength difference between left and right among multiple fastening bolts
Hull damage prevention device in hydrofoils characterized by having the door. 2. A bow strut of a hydrofoil ship is divided into flanges near the root of the hull, and this flange surface is inclined rearward and downward by a predetermined angle from a horizontal line , and left and right flanges sandwiching the strut in front view of the hull.
A hull damage preventing device for a hydrofoil ship, the surface of which is inclined from the right side to the left side of the hull . 3. A hull damage prevention apparatus according to claim 1 or 2 Symbol mounting hydrofoil consisting includes an inflatable air bag from the flange joints in the lower strut.