JPH04366041A - Vibration controlling device - Google Patents

Abstract

PURPOSE:To provide a compact tank by fulfilling a large vibration controlling effect with a small amount of stored liquid. CONSTITUTION:A wave-making plate 8 movably driven in liquid 5 by a hydraulic actuator 7 is provided in a tank 3 so that the wave-making plate 8 is driven in an earthquake to forcibly vibrate the liquid 5 for damping the vibration of a structure 1.

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 use in damping vibrations generated in structures such as buildings due to earthquakes, wind, etc.

0002

[Prior Art] Recently, a vibration damping device consisting of a tank containing a liquid such as water having a rocking frequency matching the natural frequency of the structure has been installed on the top of the structure, and vibrations generated in the structure are A proposal has been made to absorb this by the wave energy of the liquid in the tank.

0003

[Problem to be Solved by the Invention] However, in order to generate enough wave energy to absorb the vibrations of a structure using this method, the amount of liquid that must be stored inside the tank is large, and the tank Therefore, it is inevitable that the vibration damping device becomes larger. However, this type of vibration damping device is often installed in places with limited space, such as on the roof of a structure, so increasing the size of the vibration damping device poses a problem when installing other equipment such as elevators. This will cause an inconvenience.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, it is an object of the present invention to provide a vibration damping device that can exhibit a large damping effect even with a small amount of liquid and requires less installation space.

[0005]

[Means for Solving the Problems] That is, the present invention provides a vibration damping device (2) provided with a tank (3) in which a liquid (5) is stored so as to form an open liquid surface (5a) therein. A damping means (6) is provided in the liquid inside the tank, and a wave-making plate (8) is provided in the liquid inside the tank so that it can be driven back and forth. Note that numbers in parentheses are for convenience and indicate corresponding elements in the drawings, and therefore, this description is not limited to the descriptions on the drawings. The same applies to the column "(e). Effect" below.

[0006]

[Operation] With the above-described configuration, the present invention provides a tank (3)
The liquid (5) inside is forcibly vibrated by the wave-making plate (8).

[0007]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. FIG. 1 is a front view showing one embodiment of a vibration damping device according to the present invention. FIG. 2 is a front view showing another embodiment of the present invention.

As shown in FIG. 1, a vibration damping device 2 according to the present invention is disposed on the upper surface 1a of the structure 1, such as the rooftop. has a tank 3 formed into a rectangle. The longitudinal direction of the tank 3 is set in the left-right direction in the figure, and a liquid 5 is stored inside the tank 3 so as to form an open liquid surface 5a. A damping plate 6 made of a porous material such as a mesh is fixedly provided in the center of the tank 3 with its lower part submerged in the liquid 5. A bracket 3c is provided on the upper left side of the tank 3 in the figure, and a hydraulic actuator 7 is provided on the bracket 3c so that the rod 7a can be freely protruded and driven in the vertical direction, that is, in the direction of arrows C and D in the figure. It is being The tip of the rod 7a is submerged in the liquid, and a wave-making plate 8 formed from a plate-shaped member is horizontally connected to the tip. Further, a vibration sensor 9 is provided on the upper surface 1a of the structure 1, and the vibration control device 10 to which the above-mentioned hydraulic actuator 7 is connected is connected to the vibration sensor 9.

Since the vibration damping device 2 has the above-described configuration, no vibration occurs in the structure 1 under normal conditions.
The liquid level 5a of the liquid 5 stored in the tank 3 is maintained in a horizontal state as shown in FIG. Next, when the structure 1 vibrates in the horizontal directions of arrows A and B due to an earthquake, wind, etc., 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 drives the hydraulic actuator 7 to
is reciprocated in the directions of arrows C and D in a manner that matches the vibration period of the structure 1. Then, the wave-making plate 8 is also driven in the directions of arrows C and D in the liquid 5, so that the liquid 5 stored in the tank 3 directly excites waves through the tank 3 due to the shaking of the structure 1 itself. At the same time, due to the reciprocating movement of the wave-making plate 8, wave motion is started in the longitudinal direction of the tank, as shown by the solid line in the figure. The wave behavior of the liquid 5 is controlled by the vibration control device 10 so as to cancel out the vibrations generated in the structure 1, so the vibrations of the structure 1 are quickly attenuated. Note that as soon as the structure 1 starts vibrating, the vibration sensor 9 detects the vibration, and the vibration control device 10 starts the hydraulic actuator 7.
And since the liquid 5 is forcibly vibrated via the wave-making plate 8,
Rather than waiting for the liquid 5 in the tank 3 to start natural wave motion due to the vibration of the structure 1, it is possible to generate waves of a predetermined amplitude in a short time, and the damping effect can be exerted in a short time. It becomes possible.

Furthermore, even if the vibration of the structure 1 is small due to vibrations caused by a small earthquake or wind, the liquid 5 is forcibly vibrated by the wave-making plate 8, so the vibration of the structure 1 is effectively suppressed. Attenuated. Further, when the wave motion of the liquid 5 exceeds a predetermined magnitude, the vibration control device 10 stops the vibration operation via the actuator 7. Then, the wave-making plate 8 is connected to the tank 3.
It stops within and stops generating further waves. However, since a damping plate 6 made of a porous material is provided in the tank 3, the liquid 5 is undulated by the damping plate 6 during wave motion.
The liquid flows through the tank 3 in the directions of arrows A and B. Therefore, when the wave generation by the wave-making plate 8 is interrupted, the wave motion of the liquid 5 is attenuated by the damping plate 6, and the wave motion is prevented from becoming excessive and interfering with the damping operation. . The magnitude of the wave motion of the liquid 5 can be determined by pointing the wave-making plate 8 at arrows C and D.
Since it can be set arbitrarily by driving in the direction, it is possible to generate large waves and exhibit a high vibration damping effect even if the amount of liquid 5 in the tank 3 is at least.

[0011] In the above embodiment, the wave-making plate 8 was installed in a horizontal position, but the wave-making plate 8 is not limited to being installed horizontally, but can be installed in a vertical position as shown in FIG. Of course, it is okay to do so.

0012

As explained above, according to the present invention, in the vibration damping device 2 provided with the tank 3 in which the liquid 5 is stored so as to form an open liquid surface 5a inside, , a damping means such as a damping plate 6 is provided, and a wave-making plate 8 is provided in the liquid inside the tank so that it can be driven back and forth, so that the liquid 5 in the tank 3 is forcibly vibrated by the wave-making plate 8. Therefore, it is possible to generate large waves even with a small amount of liquid, and while maintaining the vibration damping effect, it is possible to reduce the amount of liquid 5 to be stored inside and downsize the tank. , it becomes possible to significantly reduce the installation area of the vibration damping device. In addition, 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 forcibly exciting the liquid 5 using a wave-making plate, so it is possible to dampen the vibration of the structure 1 in a short time. It is also extremely effective.

[Brief explanation of the drawing]

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

FIG. 2 is a front view showing another embodiment of the present invention.

[Explanation of symbols]

1...Structure 2... Vibration damping device 3...Tank 5...Liquid 5a...liquid level 6... Damping means (damping plate) 8... Wave plate

Claims (1)

[Claims] Claim 1: A vibration damping device comprising a tank storing a liquid with an open liquid surface formed therein, wherein a damping means is provided in the liquid inside the tank, and a damping means is provided in the liquid inside the tank to create waves in the liquid inside the tank. A vibration damping device consisting of a plate that can be driven back and forth.