JPS61166786A - Ship with superstructure buffer supporting device - Google Patents

Abstract

PURPOSE:To prevent the influence from being transmitted to a superstructure even if a main hull brings about sizable rolling or pitching, by making weight of the superstructure so as to be supported by one buffer capable of almost disregarding a spring constant. CONSTITUTION:Balancing piston cylinders 113 connected to each gas reservoir 114 works as a first buffer supporting device capable of almost disregarding a spring constant while supporting weight of a superstructure 2. In this state as it is, restoring force of the superstructure 2 is almost zero and an attitude of the superstructure 2 varies according to a variation in load very slowly so that a controlling piston cylinder 109 as a second buffer supporting device being supported by a servocontroller is installed there, whereby the superstructure 2 is controlled so as to keep up a state approximate to a standstill to space.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is designed to reduce the propagation rate of the effects of ship motion during waves to the superstructure. Relating to a ship with a superstructure shock absorbing support device.

[Conventional technology]

Generally, in a ship, the main hull 1 and superstructure 2 are integrated as shown in Figure 8, and the main hull 1 is
The vibration is directly transmitted to the superstructure 2. In other words, the main hull 1 and the superstructure 2 oscillate as rigid bodies.

[Problem that the invention seeks to solve]

For this reason, especially in high-speed boats, when sailing at high speed on a sea surface with waves, the oscillation and acceleration of the boat become extremely large, and the shock acceleration caused by the collision between the wave surface and the boat is also superimposed, making the ride uncomfortable (for passengers and crew). The problem is that it causes pain.

Figure 9 shows an example of the measurement results of the oscillation and vertical acceleration of a conventional high-speed boat in waves, with a length of approximately 4.
8 shows the pitching of the ship and the vertical acceleration at the bow when the ship as shown in FIG. In such a case, the waveform of the vertical acceleration includes a sharp peak that shows an impulsive change, and the amount of variation is three times that of the gravitational acceleration. Producing such a large acceleration is a serious drawback, since a downward acceleration equal to the acceleration of gravity would cause passengers to feel as if they were being lifted out of their seats.

As a means to solve such problems,
As shown in the figure, a ship in which an upper structure 2 is supported by a buffer support device 3 has been proposed by the present applicant. The schematic diagram in FIG. 5 is a side view thereof, and FIG. 5 is a plan view thereof. It is believed that most of the above-mentioned problems can be solved by appropriately designing the buffer support device 3 shown in these figures, but the present invention is directed to a ship equipped with a superstructure buffer support device equipped with such a buffer support device 3. The purpose is to provide

[Means for solving problems]

For this reason, (1) a ship with a superstructure buffer support device according to the present invention is a ship consisting of a main hull that generates buoyancy and a superstructure that is separated from the main hull and located above the main hull; A first buffer support device held on the main hull is connected to a pressurized gas tank and configured by a gas spring having a smaller volume than the tank, and a control means for holding the superstructure in a specific position. and a second shock absorbing support device.

[Effect]

According to the above-mentioned ship with the superstructure buffer support device of the present invention, the spring constant can be almost ignored! Since the weight of the superstructure is supported by the first shock absorber, even if the main hull is shaken considerably, the effect will not be transmitted to the superstructure. and a second control means for holding the superstructure in a particular position.
Since it is equipped with a shock absorbing support device, even if the weight of the upper structure shifts, changes in its posture can be minimized.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The principle of the present invention will be explained below before explaining a ship equipped with a superstructure shock absorbing device as an embodiment of the present invention with reference to nine drawings.

FIG. 5 shows a simple dynamic system in which one object 1' is suspended from another object 2' via a spring 3'. Considering the correspondence between this dynamic system and the ship with superstructure shock absorbing support shown in Figures 3 and 4, the first object 1' is the main hull 1, the second object 2' is the upper part. Structure 2. The spring 3' may correspond to the buffer support device 3. Now, a forced vertical movement is given to the first object 1' as shown in xo=xo11cosωt t: time, music, rule, music, [1]. At that time, the vertical movement of the second object 2' is X''Xecosωt・river・・・・・・・・・・・・・
・・・・・・・・・・・・・・・A・・・・It can be written as (2), but Figure 6 shows the result of calculating the ratio of the amplitude of the vertical motion of both objects. Shown below.

Here, ω. is the natural frequency of this dynamical system.

ω,=2π4π・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・It is given by [3]. K is the spring constant of the spring 3', and 9M is the mass of the object 2'.

From this figure, it is possible to keep the natural frequency determined from the mass of the superstructure 2 and the spring constant of the buffer support device 3 sufficiently low with respect to the vibration frequency of the main hull 1 in a ship equipped with a superstructure shock absorbing support device. It can be seen that if possible, the oscillation of the superstructure 2 can be made very small compared to the oscillation of the main hull 1. When we have a specific ship in mind, the vibration frequency of the main hull 1 and the mass of the superstructure 2 are fixed, so
To satisfy this condition, the spring constant K of the buffer support device 3 is
There is no other way than to make it smaller. However, if the spring constant of the buffer support device 3 is too small, the upper structure 20
There is a possibility that the weight cannot be supported, and even if the weight can be supported, there is a possibility that the attitude of the upper structure 2 will change significantly even if the weight shifts even a little within the upper structure 2.

Therefore, it can be said that a major challenge is to reduce the spring constant of the buffer support device 3 without causing such problems.

FIG. 7 shows an example of a drive mechanism of a device (a so-called wave-making device) that generates waves in a test water tank used for model tests of ships and the like. This device is.

Under the control of a servo control device 8, a driving piston cylinder 9 pushes a wave-making plate 11 whose lower end is supported by a hinge 10 to create waves. As shown by the figure, the structure is such that water does not enter behind the wave-making plate 11 where the driving device is located. Therefore, a separate mechanism is required to support the force due to hydrostatic pressure, and a balancing piston cylinder 13 filled with high-pressure gas is attached.

This piston cylinder 13 is connected to a gas reservoir 14 with a large volume, and the wave-making plate 11 moves.

In other words, it is designed to reduce the volume change rate of the enclosed gas due to the movement of the piston. 15 is a pressurized gas source.

Boyle's law P-■ = constant between the volume P of gas and the pressure V
・・・・・・・・・・・・・・・・・・・・・・・・［4
) holds, so if the volume change rate is small, the pressure will be almost constant, and the balance piston cylinder 13 can support the hydrostatic pressure acting on the wave plate 11 with a constant force regardless of the position of the piston.

By providing a piston cylinder with such functions, when considering the control of the piston cylinder 9 for driving, there is no need to consider supporting hydrostatic pressure, and there is no need to consider the influence of the piston cylinder 13 for balance. .

It is possible to perform accurate control using a very simple method.The present invention applies the principle of this drive device to a ship equipped with a superstructure shock absorbing support device. .

A first embodiment of the invention is shown in FIG. Here are 2 before and after
A set of shock absorbing support mechanisms are shown.

In reality, three to four or more sets of buffer support mechanisms will be provided, and it is not necessarily necessary to use a pair of piston cylinders for balance and control. The balance piston cylinder 113 connected to the gas reservoir 114 is a first cylinder whose spring constant is almost negligible while supporting the weight of the upper structure 20.
Acts as a support mechanism as a buffer support device (.Thus,
The natural frequency of this dynamic system is almost zero, and no matter what kind of waves the ship runs through, the frequency of oscillation is sufficiently higher than the natural frequency, so the superstructure 2 hardly sways. If this continues, the restoring force of the upper structure 2 is almost zero, so there is a risk that the posture of the upper structure 2 will change due to a very slow load change 1, for example, the movement of a passenger, causing a problem. For this purpose, a control piston cylinder 109 supported by a servo control device as a second shock absorbing support device is provided, and an appropriate control method is used to keep the upper structure 2 in a nearly stationary state with respect to the space. Control. 11
5 is a pressurized air source, and 112 is a water surface.

A second embodiment of the invention is shown in FIG. In this example, the first example in the first embodiment. Rubber air springs 209, 213 are provided in place of the piston cylinders 109, 113 as second shock absorbing support devices.

Piston cylinder 109°113 in the first embodiment
When using an air spring, there is a risk that the mechanical vibration of the device will be transmitted to the upper structure 2, and when using an air spring 209, 213, the pressure resistance strength of the air spring is generally lower than that of the piston cylinder due to the design. This could be a problem. Therefore, whether a piston cylinder or an air spring should be used for the first or second shock absorbing device depends on each individual design case, and cannot be determined.

Naturally, it is conceivable that both a piston cylinder and an air spring may be used together.

〔Effect of the invention〕

As detailed above, in the ship with the upper structure shock absorbing support device according to the present invention, the first aspect of the present invention is as follows. The piston cylinder or air spring as the second shock absorbing support device supports the weight of the upper structure while acting as a support mechanism whose spring constant is almost negligible.

In order to avoid transmitting the influence of the main hull's oscillation to the superstructure, it is only necessary to consider and control the dynamic influence.

Therefore, a piston cylinder or an air spring serving as a shock absorbing support device may have a relatively small capacity, and a device with good control characteristics that responds to high frequencies can be easily obtained. Both functions work together.

In a ship with a superstructure shock absorbing support device according to the present invention.

Even if the main hull undergoes considerable oscillation, the effect is not transmitted to the superstructure, and the superstructure can be kept nearly stationary relative to space. Therefore, if we take a single passenger ship as an example, the ride comfort will be dramatically improved, and the performance will be greatly improved. Furthermore, compared to changing the shape of the hull itself to improve performance, construction costs are lower and there is no risk of deterioration in propulsion performance, etc.

In the above embodiment, a piston cylinder and an air spring are used as examples of the shock absorbing support device, but other devices such as a mechanical type, an electric type, etc. can also be used as the second shock absorbing support device.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of a ship equipped with a superstructure shock-absorbing support device according to the present invention, Fig. 2 is a diagram showing a second embodiment of the invention, and Figs. FIG. 3 is a side view, FIG. 4 is a plan view, and FIG. 5 is an example of a high-speed boat equipped with a shock absorbing support device according to the present invention, which was previously proposed by the applicant in order to improve the structure. FIG. 6 is a diagram showing a simple dynamical system for explaining the characteristics of a ship; FIG. 6 is a diagram showing the characteristics of the simple dynamical system shown in FIG. 5; FIG. 7 is a diagram illustrating the principle of the drive mechanism of the wave-making device applied in the present invention. FIG. 8 is a diagram showing an outline of a conventional high-speed boat, and FIG. 9 is a diagram showing an example of measurement results of the oscillation and vertical acceleration of a conventional high-speed boat in waves. DESCRIPTION OF SYMBOLS 1... Main hull 2... Upper structure 3... Buffer support device 108... Control means 109... Piston cylinder as a second buffer support device 112...
Water surface 113... Piston cylinder as a first buffer support device 114... Gas reservoir 115... Pressurized air source 209... Air spring 213 as a second buffer support device... First Air spring ts as a shock absorbing support device
l prisoner fi2 Senju 3rd ward jPJ4-prisoner 8th ward Sai M(su) Suparizu

Claims (1)

[Claims] In a ship consisting of a main hull that generates buoyancy and a superstructure that is separated from the main hull and located above the main hull, a buffer support device that holds the superstructure above the main hull is connected to a pressurized gas tank. A first shock absorbing support device constituted by a gas spring having a smaller volume than that of the upper structure, and a second shock absorbing support device equipped with a control means for holding the upper structure in a specific position. Vessels with superstructure shock absorbers