JPH08133182A - Control method of shake reducing device for ship - Google Patents

Abstract

PURPOSE: To prevent frequently operating switching opening/closing control even when detected any mean period, when a valve or damper is automatically opened/closed on the basis of a mean rolling period of a ship. CONSTITUTION: A periodic range (Δt1) 11 or (Δt2) 12 and the like of certain value are set to an end of control groups 8, 9, 10, to overlap this range with the respective control groups 8, 9, similarly 9, 10 and similarly 8, 10 periodically adjacent. In each control group 8, 9, 10, control specification of respectively individual equipment operation is determined, not to execute control in charge of the other control group unless a mean rolling period is dislocated from a group during executing control. Then, what control group the mean rolling period of a ship belongs is discriminated, to execute a control signal determined in this control group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the idea of liquid braking in a shaking water tank, and relates to a control method for automatically controlling the movement or stop of liquid or the variable operation of the movement period (natural period).

[0002]

2. Description of the Related Art Conventionally, a U-tube type passive anti-swing water tank (hereinafter referred to as "ART") has been known as a device for reducing rolling of a ship. This ART is the rolling cycle of the ship and the ART
When the natural period is the same, the liquid in the ART resonates with the rolling of the ship, and a high damping effect can be obtained when a phase delay of about 90 degrees occurs with respect to the rolling, but the range is narrow. The effect is extremely reduced when the rolling cycle of the ship deviates from the ART natural cycle by about ± 1 second or more. In addition, when the rolling period of the ship becomes long (slow) outside the effective ART range for some reason, 1
It is known that it induces an unnatural sway that repeats the phenomenon of decrease and synchronism, that is, the phenomenon that the sway increases every ¼ of a sway, and in some cases causes a greater sway than without the ART. Various inventions and inventions have been made to solve the problems by providing a valve and a damper. A control method for automation of equipment operation of valves and dampers was also invented and devised, but there are many difficulties in practical use of automation as described below. Therefore, when producing ART, open type of air duct or valve with air duct Without the
Further, an ART having a conventional defect, such as a fixed natural period type which does not have means for changing the natural period of the ART, is often used. Therefore, for conventional ships equipped with these ARTs, the value of the rolling cycle of the ship, which changes every moment due to the influence of the encountering period in the voyage condition and the sea meteorological condition, etc., is grasped by many years of experience and stopwatch etc. A to change the cycle each time, or to prevent entrainment roll
I was operating the RT inactive. The operation method will be described with reference to the ART shown in FIG. When the valve 5 of the air duct 4 is provided, the valve 5 is opened when operating, or the valve 5 is closed when stopping. (B). If the valve 5 of the air duct 4 is not provided, when it is operated, the ART body 6 has 1 to 4% of the drainage amount.
When injecting or stopping the required amount of the liquid 14, the liquid 14 is also drained. Further, when the ART natural cycle is slowed (long), the damper 3 in the liquid passage 2 is closed, and when the ART natural cycle is quickly (shortened), the damper 3 is opened, which requires a great burden on the crew. I was hanging.

Therefore, as one countermeasure, when the cycle in which the ART causes an adverse effect is detected, the valve 5 is automatically closed to deactivate the ART, and when the cycle in which the ART effectively operates is detected from this state, A swinging method of opening the valve 5 and activating the ART was invented (for example, Japanese Patent Publication No. 58-3).
0196).

[0004]

However, as shown in FIG. 2, the average rolling period of the ship is the control reference value (the rolling angle of the ship becomes larger when the rolling angle is in operation than when it is not operating. (Point) In the conventional method of discriminating only the magnitude relation with respect to T1 or T2, when a rolling motion around the control reference value T1 or T2 occurs, a switching control signal to the switchgear device is frequently output. However, for electric motors for hydraulic pumps required to drive the switchgear, frequent inching of the power switch must be avoided as much as possible from the balance of starting power, etc., and frequent inching consumes the corresponding equipment. However, the operation related to the adjustment of the ART natural period is still a manual operation because the control is not suitable as a control method. It was bought. As described above, in the conventional valve control method, the effective range 7 is narrowed only by automatically opening and closing the valve to control the operating or non-operating state of the ART when the period in which the ART causes the adverse effect is detected. The other drawback cannot be compensated, and the problem remains that a stable operation state is not always formed, and the effectiveness of the anti-sway device is not fully exerted at present.

[0005]

[Purpose] The control required by ART is to make it possible to vary the natural period of the liquid as well as braking the liquid, and to respond to a wide range of rolling periods. The present invention has been made in order to solve the above-mentioned conventional problems. Even when the average rolling period of a ship is a control reference value T1 or a period near T2, the valve can be opened and closed without frequent opening and closing operations. Control is, of course, intended to provide an automatic control method that allows a damper-driven hydraulic pump electric motor to be operated and stopped for only a few seconds when needed.

[0006]

As shown in FIG. 3, the basic configuration of the ART itself for achieving the above object is a pair of at least two wing tanks 1a, which are set on both sides of the hull. 1b and these wing tanks 1a, 1
Liquid passage 2 for moving liquid 14 in the left-right direction at the bottom of b
Although not shown, the air duct 4 is connected to the upper part of the wing tanks 1a and 1b and communicates with the wing tanks 1a and 1b through a valve 5 and is equipped with necessary fittings such as a pouring / draining pipe, a sounding pipe, and an air vent pipe. The ART main body 6 is provided with a closing means for all the pipes such as the above-mentioned pouring / draining pipes, sounding pipes, and air vent pipes so that they can be hermetically sealed. Further, the liquid passage 2 is divided into a plurality of parts for changing the ART natural period, and a damper 3 and the like are provided therein. A power drive type for automatic control is adopted for opening and closing the valve 5 or the damper 3, but it is assumed that the valve 5 or the damper 3 is fully closed or fully opened without any intermediate opening.
A control device mechanism as shown in FIG.

The control method includes a control group 8 having at least two or more different cycle ranges according to the purpose of ART.
9 and 10 are formed, and operation specifications for device control are set for each group. Then, unless the average rolling cycle deviates from the group under control, the control under the control of other groups is not executed. Therefore, it is determined which control group the average rolling period of the ship belongs to, and the predetermined control signal of that group is executed.

Here, the setting of the control groups 8, 9 and 10 will be described. In FIG. 4, the vertical axis shows the ratio of the ship inclination angle (rolling angle) to the wave inclination angle, and the horizontal axis shows the rolling cycle, showing the rolling behavior of the ship in each cycle. ART
The effective range 7 is generally from T1 to T2, which is the branching point of the damping effect, in which the rolling angle of the ship is larger when the ship is not operating. However, this effective range 7
It is near the ART natural period that a high vibration reduction effect is obtained, and the vicinity of the branch point T1 or T2 (Δ
The effects in t1) 11 or (Δt2) 12 and (Δt3) 13 are low, and even if the ART is activated or deactivated, the majority of the anti-sway effect is hardly affected.

Therefore, the portions of the control groups 8, 9 and 10 that are periodically adjacent to each other are (Δt1) 11 or (Δt1).
2) The 12 or the like is overlapped so that the cycle determination value has a range. This (Δt1) or (Δt2)
The values such as "etc." are appropriately determined according to the purpose of ART control.

[0010]

With respect to the operation relationship of the above-described embodiment of the present invention, the operation of the opening / closing device such as the valve 5 and the damper 3,
That is, since the cycle determination reference values T1 and T2 at the time of opening and at the time of closing are not the same point but different, the frequent operating state of each device at the control switching point is reduced, so that a larger torque than the valve 5 is used. By using an electric motor or the like as the drive source of the damper 3 that requires, automatic control is possible. The factor that causes the adverse effect of ART is that the effective range 7 is narrow, and automation of the damper 3 expands the effective operating range 15, and it becomes possible to eliminate the fatal defect of ART. In addition, the life of the equipment will be dramatically extended due to the extremely reduced use frequency.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be further described below with reference to the drawings. As shown in FIG. 2, the opening / closing operation mechanism includes a control unit 18 that controls numerical operations and control signals, and an opening / closing device unit 19. The control unit 18 measures the rolling condition of the ship for each sway with an inclination sensor 20 such as an inclinometer, and obtains a single cycle value by computer processing. AR
As described above, the operating principle of T is that a high damping effect can be obtained when a phase delay of about 90 degrees with respect to rolling is obtained, so it is sufficient to grasp the situation of the rolling cycle in the near future. The rolling average of time is not practical. Therefore, the average rolling period is calculated by averaging two to five single periods, and a moving average method is used in which a new value is always included and an old value is removed. Which of the groups 8, 9 and 10 to which the calculated average value belongs, which will be described later with reference to FIG. 1, is discriminated and a control signal preset to the corresponding group 8, 9 and 10 is transmitted. Further, the operation status of each device is grasped by the information processing circuit 23 one by one, and the information is stored in the IC memory and displayed on the control panel (not shown). Although not shown, conditions such as the inclination angle and the cycle can be transmitted to other navigation equipment as navigation information.

The switchgear device unit 19 comprises a drive unit 24, solenoid valves 25, 28, switchgear devices 26, 29, limit switches 27, 30 and the like. The open / close control of the device is to start the drive unit 24 by the control signal from the control unit 18 → electromagnetic valves 25 and 28 → open / close devices 26 and 29 → limit switches 27 and 30 → stop the drive unit 24. The drive unit 24 may not be required depending on the mechanism. For example, when the drive source can be directly supplied from another line, the steps of starting and stopping the driving machine 24 can be omitted.

In this embodiment, the device for the valve 5 and the damper 3 are used.
In the example in which one set of each device is provided, each group 8, 9, 10
Is a certain periodic range (Δt1) in the vicinity of periodically adjacent
11 or the same (Δt2) 12 and the same (Δt3) 1
The value of 3 overlaps each other and the effective operating range is 15
Is as shown in FIG.

In order to make it easy to understand, a specific numerical value will be set and each control group 8, 9, 10 will be described. (I). The non-operation (CASE-1) 8 means that the valve 5 is operated when the average period value is 11.6 seconds or more and 7.8 seconds or less.
Is forcibly closed and the ART is deactivated. This state is maintained until the average period enters between 11 seconds and 8.5 seconds like the case of non-operation (CASE-1a) 8a. (B). In the operation (CASE-2) 9, the value of the average period is within the range of 11.6 seconds to 9.4 seconds, and the valve 5 is opened and the damper 3 is closed, and the state is maintained. (C). The operation (CASE-3) 10 executes and holds the control for opening the valve 5 and opening the damper 3 when the value of the average period is within the range of 10 seconds to 7.8 seconds. These control specifications are executed when the value of the average period leaves the group in which the control is being executed and enters the corresponding group.

[0015]

As is apparent from the above description, according to the present invention, the valve control is, of course, easy, and the damper control is easy, and the operation and stop operation are required for a few seconds only when necessary, which is troublesome. Not automatically. This is a fatal drawback of ART, that is, the narrow effective range and the adverse effect when it goes out of the effective range can be easily eliminated. Therefore, in a vessel equipped with an ART equipped with the number of valves and dampers suitable for the vessel, the ART which seems to be the most suitable for the rolling cycle of the vessel which is constantly changing due to the influence of the encountering period and the sea weather condition. The effective operating range is expanded, such as automatically changing the natural period or even when encountering the rolling period that gives the above-mentioned adverse effect, the ART can be deactivated to prevent the synchronized rolling.
It is an invention that has a large effect industrially because it has a function and effect that a stable vibration reduction effect is always obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an effective operation range and an operation relationship in the present invention.

FIG. 2 is a block diagram showing a structural relationship of an opening / closing operation mechanism of a valve or damper according to the present invention.

FIG. 3 is an overall configuration diagram showing a schematic configuration of ART.

FIG. 4 is a chart showing an effective operating range of ART.

[Explanation of symbols]

1a, 1b ... Wing tank, 2 ... Liquid passage 3 ... Damper, 4 ... Air duct 5 ... Valve, 6 ... A
RT main body 7, 7a, 7b ... Effective range, 8, 8a, 9, 10 ... Control execution range (control group) 11, 12, 13 ... Overlapping cycle range (Δt1,
Δt2, Δt3) 14 ... Liquid, 15 ...
Effective operating range 18 ... Control section, 19 ...
Switchgear device unit 20 ... Inclination sensor, 21 ...
Period calculation determination circuit 22 ... Control circuit, 23 ...
Information processing circuit 24 ... Driving source, 25, 28
... Solenoid valve 26 ... Valve opening / closing device, 27, 30
・ ・ ・ Limit switch 29 ・ ・ ・ Damper opening / closing device, 30 ・ ・ ・
Information processing circuit

Claims (1)

[Claims] 1. A control switching point when a valve (5) with an air duct (4) or a damper (3) in a liquid passage (2) is automatically opened and closed based on the average rolling period of the hull. Effective range (7a, 7b) in order to have width
The control method is characterized in that the switching of the opening / closing control does not frequently operate by overlapping one part of the above with a cycle range (11, 12, 13) of a certain value.