JPH0593476A - Damping device - Google Patents

Abstract

PURPOSE:To prevent excitation of a structure by a method wherein when vibration of a structure detected by a vibration detecting means exceeds a given value, a damping means is opened in the direction of wave motion and when vibration is below a given value, the damping means is closed in the direction of wave motion. CONSTITUTION:When a structure 1 is vibrated in the direction of arrow marks A and B owing to earthquake and wind, liquid 5 stored in a tank 3 is caused to excite wave motion through the tank 3 owing to vibration of the structure 1 itself. Since wave motion is set according to the resonance frequency of the structure 1, vibration of the structure 1 is rapidly damped. The magnitude of vibration is always monitored by a vibration sensor 20. When vibration of the structure 1 is high and a high damping force is needed, based on a vibration detecting signal S1 from the vibration sensor 20, an opening closing control device 19 commands opening of a damping plate 6 to an opening closing drive mechanism l7. The control part 19 opens the damping plate 6 in the direction of an arrow mark C. Since a damping means is rendered ineffective in the direction of wave motion, the liquid 5 sufficiently continues motion of wave and a high damping effect against vibration of the structure 1 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device suitable for attenuating vibration generated in a structure such as a building due to an earthquake or wind.

[0002]

2. Description of the Related Art Recently, a vibration damping device consisting of a tank storing a liquid such as water having a rocking frequency matching the natural frequency of the structure has been installed on the upper part of the structure, and vibration generated in the structure has been installed. It has been proposed to absorb the wave energy of the liquid in the tank.

[0003]

Normally, this type of vibration damping device is provided with a damping member for damping the wave motion of the liquid inside the tank, but the vibration of the structure is large and the high damping force is high. If it is necessary to suppress the vibration of the liquid as much as possible without providing damping means, on the other hand, when the vibration converges, if the vibration of the liquid in the tank remains forever, The resulting vibration is generated in the structure, which causes a problem that the vibration of the structure cannot be contained forever.

In view of the above circumstances, the present invention can exert a high damping force when the vibration of a structure is large,
An object of the present invention is to provide a vibration damping device that can quickly damp the residual vibration of the liquid inside the tank when the vibration converges.

[0005]

That is, the present invention provides a vibration damping device (2) provided with a tank (3) for storing a liquid (5) in a form of forming an open liquid surface (5a), Damping means (6) is provided in the liquid in the tank so as to be openable and closable in the wave direction of the liquid, and vibration detection means (20) for detecting the vibration of the structure (1) is provided. When the vibration of the structure detected by the vibration detecting means is greater than or equal to a predetermined value, the damping means is opened in the wave direction, and when the vibration is less than or equal to the predetermined value, the damping means is moved in the wave direction. The opening / closing control means (17, 19) for controlling to close the control unit is provided. It should be noted that the numbers in parentheses indicate the corresponding elements in the drawings for the sake of convenience, and thus the present description is not limited to the description in the drawings. The same applies to the section "(e). Action" below.

[0006]

With the above structure, the present invention provides a structure (1)
When a large vibration is required and a high damping effect is required, the damping means is opened to cause the liquid to vibrate without being damped in the wave direction, and when the vibration of the structure (1) has converged, the damping means To act to dampen residual vibrations of the liquid (5).

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing an embodiment of a vibration damping device according to the present invention, FIG. 2 is a plan view of the tank portion of FIG. 1, and FIG. 3 is an amplitude-time diagram showing a vibration mode of a liquid.

As shown in FIGS. 1 and 2, a vibration damping device 2 according to the present invention is arranged on the upper surface 1a of the roof of the structure 1, and the vibration damping device 2 is as shown in FIG. The tank 3 has a rectangular planar shape. Tank 3
The longitudinal direction is set to the left-right direction in the figure, and the liquid 5 is stored inside the tank 3 in the form of forming an open liquid surface 5a. Damping plates 6, 6 made of a porous material such as a mesh are provided in a central portion of the tank 3 so as to face each other, and the damping plates 6, 6 are submerged in the liquid 5 and as shown in FIG. Damping plates 6, 6 are provided so as to be openable and closable around pins 6a in the directions of the middle arrows C, D, that is, the wave direction of the liquid 5, and the damping plates 6, 6 are further provided with an opening / closing drive mechanism 17 including an actuator. It is connected. Open / close drive mechanism 17
The open / close control device 19 is connected to the open / close control device 19, and the open / close control device 19 is connected to the vibration sensor 20 mounted on the upper surface 1 a of the structure 1.

Since the vibration damping device 2 has the above-described structure, the structure 1 does not vibrate in a normal state.
The liquid surface 5a of the liquid 5 stored in the tank 3 is held in a horizontal state as shown in FIG. Next, if the structure 1 vibrates in the horizontal arrow A and B directions due to an earthquake or wind,
The liquid 5 stored in the tank 3 is excited by the vibration of the structure 1 itself via the tank 3. Liquid 5
Since the wave of is set according to the resonance frequency of the structure 1, the vibration of the structure 1 is quickly attenuated by the vibration of the liquid 5. The magnitude of the vibration of the structure 1 is constantly monitored by the vibration sensor 20, and when the vibration of the structure 1 is large and a large damping force is required, the vibration sensor 20 is used.
Based on the vibration detection signal S1 from the opening / closing controller 19, the opening / closing controller 19 commands the opening / closing drive mechanism 17 to open the damping plate 6.
In response to this, the opening / closing control unit 19 opens the damping plate 6 in the arrow C direction. Then, since the liquid 5 in the tank 3 does not have any damping means in the wave direction, the wave can be sufficiently continued and a strong vibration damping effect against the vibration of the structure 1 can be exhibited. .

When the swing of the structure 1 tends to converge and the wave height of the liquid 5 in the tank 3 also becomes small, as it is, as shown in FIG. 3, after the time T1, on the contrary, Since the residual vibration of the liquid 5 causes the structure 1 to vibrate, the opening / closing control device 19 drives the opening / closing based on the detection signal S1 from the vibration sensor 20 when the vibration of the structure 1 becomes a predetermined value or less. The mechanism 17 is instructed to close the damping plate 6. In response to this, the opening / closing control device 19 closes the damping plate 6 in the direction of the arrow DC. Then, the tank 3 is closed by the damping plates 6 and 6 at the central portion thereof, and the liquid 5 cannot continue the wave motion unless it passes through the damping plates 6 and 6, and the liquid 5 is damped. As a result, the wave energy is absorbed and rapidly attenuated as shown by the one-dot chain line in FIG. 3, and the residual vibration of the liquid 5 is prevented from being transmitted to the structure 1.

[0011]

As described above, according to the present invention, in the vibration damping device 2 in which the tank 3 storing the liquid 5 in the form of the open liquid surface 5a is provided, in the liquid of the tank, Damping means such as a damping plate 6 is provided so as to be openable and closable with respect to the wave direction of the liquid such as arrow A and B directions, and vibration detecting means such as a vibration sensor 20 for detecting vibration of the structure 1 is provided to detect the vibration. The damping means is opened in the wave direction when the vibration of the structure 1 detected by the vibration detecting means is equal to or more than a predetermined value, and the damping means is opened when the vibration is less than or equal to the predetermined value. Opening / closing control device 19 for controlling so as to close the wave direction and opening / closing drive mechanism 1
Since the opening / closing control means such as 7 is provided, the structure 1
If a large vibration is required and a high damping effect is required, the damping means is opened to vibrate the liquid without damping it in the wave direction, and when the vibration of the structure 1 has converged, the damping means is By closing, the residual vibration of the liquid 5 can be damped, and the structure 1 can be prevented from vibrating due to the vibration. Therefore, it is possible to provide a vibration damping device having a high vibration damping effect and less residual vibration of the liquid stored inside.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a vibration damping device according to the present invention.

2 is a plan view of the tank portion of FIG. 1,

FIG. 3 is an amplitude-time diagram showing a vibration mode of a liquid.

[Explanation of symbols]

 1 ... Structure 2 ... Damping device 3 ... Tank 5a ... Liquid level 6 ... Damping means (damping plate) 17 ... Open / close control means (open / close drive mechanism) 19 ... Open / close control means (open / close control device) ) 20 ... Vibration detection means (vibration sensor)

Claims (1)

[Claims] 1. A vibration damping device provided with a tank for storing a liquid therein so as to form an open liquid surface, wherein damping means is provided in the liquid of the tank so as to be openable and closable in the wave direction of the liquid. A vibration detecting means for detecting the vibration of the structure is provided, and when the vibration of the structure detected by the vibration detecting means is equal to or more than a predetermined value, the damping means is provided with respect to the wave direction. A vibration damping device configured to include an opening / closing control unit that opens and controls the damping unit to close in the wave direction when the vibration is below a predetermined value.