JPH0598843A - Damping device - Google Patents

Abstract

PURPOSE:To damp the extent of vibration in a structure and secure a damping effect with a limited storage of liquid as well as to miniaturize a tank by installing an air nozzle in this tank, feeding compressed air in the liquid at the time of an earthquake, and exciting the liquid so forcibly. CONSTITUTION:A liquid 5 is stored in a tank 3, and when a structure 1 is horizontally vibrated in both arrow A, B directions by an earthquake and a strong wind or the like, a vibration sensor 9 detects it, outputting a signal S1 to an excitation controller 10. Next, this controller 10 accords a selector valve 12 with a vibro-period of the structures 1, selecting the period, and an air compressor 13 and two air nozzles 3b, 3c are interconnected in an alternate manner. In succession, compressed air 15 is fed to these air nozzles 3b, 3c alternately from the air compressor 13 at the specified period, discharging it into the liquid 5 in the tank 3. In addition, the liquid 5 receives push-up force to the upper part alternately at both sides of the tank 3, starting its wave motion in both arrow A, B directions. In this connection, the liquid 5 stored in the tank 3 excites a rectilinear wave motion in both these arrow A, B directions even by a shake of the structure 1 itself.

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]

However, in order to generate sufficient wave energy to absorb the vibration of the structure by such a method, the amount of liquid to be stored inside the tank is large, and the tank is inevitably inevitable. Therefore, it is inevitable that the vibration damping device becomes large. However, since this type of vibration damping device is often installed in a place with a limited space, such as a rooftop of a structure, a large size of the vibration damping device is an obstacle to installation of other equipment such as an elevator. Inconvenience occurs.

In view of the above circumstances, it is an object of the present invention to provide a vibration damping device which can exert a large vibration damping effect even with a small amount of liquid and requires a small installation space.

[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 tank (3), air supply parts (3b, 3c) are provided at the bottoms on both sides in the wave direction of the tank, and air (15) is supplied to the inside of the tank. , An air supply control means capable of alternately supplying air to the air supply unit (1)
0, 12, 13) are connected. 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 the tank (3).
The liquid (5) therein acts so as to be forcibly excited by the air (15) alternately supplied from the air supply unit. To work.

[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.

As shown in FIG. 1, 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 has a planar shape as shown in FIG. Has a tank 3 formed in a rectangular shape. The longitudinal direction of the tank 3 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. A damping plate 6 made of a porous material such as a mesh is provided in the center of the tank 3 so as to be submerged in the liquid 5, and the upper portion of the damping plate 6 extends above the liquid surface 5a.
Air nozzles 3b and 3c are provided at the lower portions of the wall surfaces 3a and 3a on both sides in the directions of arrows A and B, which are the wave directions of the liquid 5 in the tank 3, with their tips opened inside the tank. Is connected to a switching valve 12 via air pipes 11, 11. An air compressor 13 and a vibration control device 10 are connected to the switching valve 12,
A vibration sensor 9 provided on the upper surface 1a of the structure 1 is connected to the vibration control device 10.

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 vibration sensor 9 detects the vibration and outputs a vibration detection signal S1 to the vibration control device 10. In response to this, the vibration control device 10 switches the switching valve 12 at an appropriate cycle that matches the vibration cycle of the structure 1, and alternately connects the air compressor 13 and the air nozzles 3b, 3c. Then, the compressed air 15 is alternately supplied from the air compressor 13 to the air nozzles 3b and 3c through the switching valve 12 at a predetermined cycle, and the supplied compressed air 15 is supplied to each of the air nozzles 3.
The liquid is discharged from b and 3c into the liquid 5 in the tank 3. The discharged compressed air 15 becomes bubbles 15a and rises in the liquid 5, but at this time, the upward pushing force acts on the liquid 5. Since the compressed air 15 is alternately discharged into the liquid 5 from the air nozzles 3b and 3c, the liquid 5 is stored in the tank 3
On both sides in the figure, the upward pushing force is alternately applied to start wave motion in the directions of arrows A and B. The liquid 5 stored in the tank 3 can directly excite waves in the directions of arrows A and B due to the shaking of the structure 1 itself through the tank 3. Further, the wave mode of the liquid 5 is controlled by the vibration control device 10 so as to cancel the vibration generated in the structure 1 by controlling the supply cycle of the compressed air 15 from the air nozzles 3b and 3c. The vibration of the structure 1 is quickly damped. As soon as the structure 1 starts vibrating, the vibration sensor 9 detects the vibration, and the vibration control device 10 forcibly vibrates the liquid 5 via the switching valve 12 and the air nozzles 3b and 3c. Tank 3 due to vibration of object 1
It is possible to generate a wave having a predetermined amplitude in a short time rather than waiting for the liquid 5 inside to start a natural wave, and it is possible to exhibit a vibration damping effect in a short time.

Further, even if the vibration of the structure 1 is small due to the vibration caused by a small earthquake or wind, the liquid 6 is forcibly excited by the compressed air 15, so that the vibration of the structure 1 is effectively damped. To be done. Further, when the wave motion of the liquid 5 exceeds a predetermined magnitude, the vibration control device 10 stops the vibration operation by the compressed air 15. Then, the liquid 5 becomes the tank 3
The liquid 5 is vibrated by passing through the damping plate 6 arranged in the center of the tank 3 in the horizontal direction in the drawing.
The wave of is damped by the damping plate 6, and the wave is prevented from becoming excessive and obstructing the vibration damping operation.
The magnitude of the wave of the liquid 5 is determined by the air nozzles 3b and 3c.
The supply amount of the compressed air 15 from the air compressor 13, and hence the supply pressure of the compressed air 15 from the air compressor 13 to each of the air nozzles 3b and 3c, can be arbitrarily set by the vibration control device 10 appropriately controlling the tank. Liquid 5 in 3
When the amount is at least, a large wave can be generated, and a high vibration damping effect can be exhibited.

[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, the damping plate is provided in the tank 3. A damping means such as 6 is provided, and arrows A and B of the tank are provided.
Air nozzles 3b and 3c on the bottom of both sides of the wave direction
Are provided so that air such as compressed air 15 can be supplied to the inside of the tank, and the air supply unit includes the vibration control device 10, the switching valve 12, the air compressor 13, and the like. Since the air supply control means capable of alternately supplying air to the parts is connected, the liquid 5 in the tank 3 is forcibly excited by the air alternately supplied from the air supply part. Therefore, it becomes possible to generate a large vibration even with a small amount of liquid, and to exert a great damping effect, while maintaining the damping effect.
By reducing the amount of the liquid 5 to be stored inside, it is possible to reduce the size of the tank, and it is possible to significantly reduce the installation area of the vibration damping device. Even if the vibration of the structure 1 is small, the vibration of the structure 1 can be effectively damped in a short time by supplying air into the liquid 5 from the air supply unit and forcibly exciting the liquid 5. Because it can be done, it is extremely effective in the event of wind and small earthquakes.

[Brief description of drawings]

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

[Explanation of symbols]

 1 ... Structure 2 ... Damping device 3 ... Tank 3b, 3c ... Air supply part (air nozzle) 5a ... Liquid level 6 ... Damping means (damping plate) 10 ... Air supply control means (vibration) Control device) 12 ... Air supply control means (switching valve) 13 ... Air supply control means (compressor) 15 ... Compressed air

Claims (1)

[Claims] 1. A vibration damping device having a tank for storing liquid in the form of an open liquid surface, wherein damping means is provided in the tank, and air supply parts are provided at bottoms on both sides in the wave direction of the tank. , A vibration damping device which is provided so that air can be supplied to the inside of the tank, and an air supply control means capable of alternately supplying air to the air supply unit is connected to the air supply unit. ..