JPH08200436A - Fluid type vibration exciting and vibration damping device - Google Patents

Abstract

PURPOSE: To provide a prescribed vibration frequency, vibration exciting force of large phase and vibration damping force by small driving force. CONSTITUTION: A device comprises a closed tank 1 of holding a level of liquid 2 in a central part 4 higher than in a peripheral part 3 by a differential pressure acting in a liquid surface, U-shaped vessel 5 receiving the liquid 2 also to be divided into two chambers 5a, 5b by an underliquid flat plate 7 arranged in the liquid with the one chamber 5a opened to the atmosphere, communication pipe 6 of connecting the other chamber 5b of the U-shaped vessel 5 and the central part 4 of the tank 1 to receive gas, drive source 11 of turning the underliquid plate 7 and a control device 12 of controlling the drive source. By rotating the underliquid flat plate 7, vibration exciting force is generated in the liquid 2 in the tank 1, and further by adjusting the differential pressure acting in the liquid surface, a resonance phenomenon is generated in the tank 1 to obtain large vibration exciting force and vibration damping force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid type vibration / damping device applied to vibration proof of a large structure or the like.

[0002]

2. Description of the Related Art FIG. 2 shows a state where a conventional unbalanced weight type vibration device (014) is mounted on a structure (013) and vertically vibrated. In this vibrating device, one unbalanced weight (015) is rotated to cancel the unbalanced force in the left-right direction, and only the unbalanced force in the up-down direction indicated by the arrow is left so that the vibration can be performed in the up-down direction. There is.

[0003]

Large structures such as ships and bridges have a large weight, and the conventional vibration exciter described above has a small vibration force in the low frequency range, which makes vibration damping particularly difficult.

The present invention provides a fluid type vibration / vibration damping device which resonates the vibration frequency of a vibration system of a tank to a required frequency to obtain a large vibration / damping force. It is the one we are trying to provide.

[0005]

SUMMARY OF THE INVENTION A fluid type vibration / vibration damping device according to the present invention is a sealed tank in which the liquid level in the central portion is kept higher than that in the peripheral portion due to the pressure difference acting on the liquid surface. , A U-shaped container in which a liquid is contained and is divided into two chambers by a submerged plate disposed in the liquid, and one of the two chambers is open to the atmosphere, and two chambers of the U-shaped container And a communication pipe containing a gas that connects the other chamber of the tank to the center of the tank, a drive source for rotating the submerged plate, and a control device for controlling the drive source.

[0006]

In the present invention, when the submerged plate in the U-shaped container is rotated, the liquid level in the two chambers divided by the submerged plate fluctuates and is communicated with the other chamber by the communication pipe. Further, the pressure acting on the liquid surface of the liquid in the central part of the sealed tank fluctuates and the liquid level moves up and down, and the liquid in the tank moves up and down inside the central part and the peripheral part. An inertial force based on the vertical movement of the liquid in the tank acts as an exciting force. The vibration frequency, phase, and magnitude (amplitude) of this exciting force can be set to desired values by controlling the drive source that rotates the submerged plate by the control device.

Further, the pressure acting on the liquid surface in the central portion and the peripheral portion of the sealed tank causes a difference in liquid level between the central portion and the peripheral portion of the tank, but the pressure acting on the peripheral portion of the tank is changed. As a result, the effective pipeline length, which is the height from the liquid level in the peripheral portion of the tank to the liquid level in the central portion, changes, and the natural frequency of the tank changes accordingly. As a result, the natural frequency of the tank can be made equal to or close to the frequency of the above-mentioned exciting force, and a resonance phenomenon can be generated to obtain a large exciting force having a predetermined frequency with a small driving force. it can.

Further, according to the present invention, the rotation of the submerged plate is controlled by the control device based on the vibration of the structure and the like, and the difference in the differential force acting on the liquid surface at the central portion and the peripheral portion of the tank is appropriately adjusted. By setting, as mentioned above, the magnitude of the excitation force,
The phase and frequency can be set to appropriate values, and the vibration frequency of the tank can be matched with the vibration frequency of the structure, etc. by acting as a vibration suppressor. Can function as a vibration damping device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIG. A sealed tank 1 containing a liquid 2 is installed on a vibrating structure 13. The tank 1 is divided into a central portion 4 and two peripheral portions 3 on both sides thereof, and the bottom portions of the central portion 4 and the peripheral portion 3 communicate with each other.

Reference numeral 5 is a U-shaped container containing the liquid 2,
The inside of the letter-shaped container 5 is divided into two chambers 5a and 5b by a submerged flat plate 7 whose upper end is pivotally supported by the lower end of a central partition wall 5 '. The chamber 5a is open to the atmosphere, and the chamber 5b is connected to the upper part of the central portion 4 of the tank 1 by a communication pipe 6 containing a gas. The submerged plate 7 can be rotated by a drive source 11 around a pivot point of an upper end as shown by an arrow.

The upper portion of each peripheral portion 3 is a solenoid valve 1.
The pressure source 9 can be connected via 0'and the atmosphere can be connected via a solenoid valve 10. Reference numeral 12 denotes a control device. The control device 12 receives a signal of a vibration 13 'of the structure 13 and sends the signal to the solenoid valves 10, 10' and the drive source 11 to control them. Has become.

Inside the central portion 4 of the tank 1 and the U-shaped container 8
Below the inside of the liquid surface, a damping wire net 8 for adjusting the liquid surface fluctuation is provided.

In this embodiment, the electromagnetic valve 10 is closed and the electromagnetic valve 10 'is opened in response to a signal from the control device 12 to supply gas from the pressure source to the upper portion of the peripheral portion 3 of the tank 1 so that the liquid level of the peripheral portion 3 is increased. The acting pressure P is generated, and the liquid level in the central portion 4 is kept higher than the liquid level in the peripheral portion 3 due to the difference in force acting on the liquid surface.

The case where the present embodiment is used as a vibrating device will be described below. When the liquid submerged flat plate 7 is rotated around the pivot point of the upper end in the arrow direction by the drive source 11, the submerged flat plate 7
The liquid level of the liquid 2 in the chambers 5a and 5b divided by the up and down moves up and down, and accordingly, the pressure acting on the liquid surface of the central portion 4 of the tank 1 connected to the chamber 5b by the communication pipe 6 changes. Then, the liquid level of the liquid in the central portion 4 moves up and down, and the liquid 2 in the tank 1 moves up and down in the central portion 4 and the peripheral portion 3 as shown by the arrow. An inertial force based on the vertical movement of the liquid 2 in the tank 1 acts on the structure 13 as an exciting force. The frequency and phase of this exciting force can be set to desired values by controlling the drive source 11 by the controller 12 and controlling the rotation of the submerged flat plate 7. Further, by controlling the angle of rotation of the submerged flat plate 7 by the control device 12, the magnitude (amplitude) of the exciting force can be adjusted.

On the other hand, the control device 12 controls the solenoid valve 10,
The liquid level difference between the peripheral portion 3 and the central portion 4 is changed by controlling 10 'to adjust the pressure acting on the liquid surface of the peripheral portion 3 of the tank 1. As a result, the effective pipeline length, which is the height from the liquid level in the peripheral portion 3 of the tank 1 to the liquid level in the central portion 4, changes, and the natural frequency of the tank 1 changes accordingly.

As described above, by changing the natural frequency of the tank 1, this can be made to match or approach the frequency of the exciting force, and a resonance phenomenon can be caused. As a result, a large driving force having a predetermined frequency can be applied to the structure 13 with a small driving force.

When the present embodiment is used as a vibration damping device, signals of amplitude, frequency and phase of vibration of the structure 13 are input to the control device 12, which causes the control device 12 to drive the drive source 11 and the electromagnetic wave. Control the valves 10, 10 '.

By controlling the drive source 11, as described above, the rotation of the submerged flat plate 7 is controlled to control the vibration force due to the vertical movement of the liquid 2 in the tank 1, and the solenoid valves 10 and 10 are controlled. By controlling ′, as described above, the pressure P acting on the liquid surface of the peripheral portion 3 of the tank 1 can be changed to cause the resonance phenomenon between the tank 1 and the exciting force.

Therefore, in this embodiment, based on the signal from the control device 12 to which the signal of the vibration 13 'of the structure 13 is input, the amplitude and frequency of the vibration 13' are equal and the phase is It is possible to generate the opposite excitation force, and it is possible to effectively suppress the vibration.

In the above embodiment, the two peripheral portions 3 are provided on both sides of the central portion 4 of the tank 1. However, the gas phase portions of these peripheral portions 3 may be communicated with each other. The pressure source 9 and the solenoid valves 10 and 10 'can each be one.

[0021]

As described above, according to the present invention, the liquid in the tank is moved by the rotation of the submerged plate of the U-shaped container to generate an exciting force, and the fluid in the tank is vibrated as described above. By causing a force and a resonance phenomenon, a large driving force can be applied to the structure with a small driving force. Also, the excitation force is made to match the frequency of the structure, and
The phase can be reversed to the vibration of the structure or the like, and a large damping effect can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a conventional unbalanced weight type vibration device.

[Explanation of symbols]

 1 Tank 2 Liquid 3 Peripheral part of tank 4 Central part of tank 5 U-shaped container 5'Partition walls 5a, 5b Chamber 6 Communication pipe 7 Flat plate in liquid 8 Damping wire mesh 9 Pressure source 10, 10 'Solenoid valve 11 Drive source 12 Controller 13 Structure 13 'Structure vibration

Claims (1)

[Claims] 1. A sealed tank in which the liquid level of a central portion of the liquid is kept higher than that of the peripheral portion due to a pressure difference acting on the liquid surface, and a submerged plate which contains the liquid and is arranged in the liquid. A U-shaped container that is divided into two chambers and one of the two chambers is open to the atmosphere, and a gas that connects the other chamber of the two chambers of the U-shaped container to the central portion of the tank Communication tube, a drive source for rotating the submerged plate,
And a fluid type vibration / vibration damping device comprising a control device for controlling the drive source.