JPH0571575A - Vibration suppressing device - Google Patents

Abstract

PURPOSE:To reduce the installation space by allowing a small quantity of liquid to develop a large brake lowering by installing a damping means in shiftable manner in the horizontal direction in the liquid in the center part in the wave motion direction in a tank and connecting a reciprocating driving means which shift-drives the damping means in the horizontal direction, with the damping means. CONSTITUTION:When a structure I vibrates horizontally, a vibration sensor 9 detects this vibration, and outputs a signal to a vibration suppressing device 10. The vibration suppressing device 10 drives a hydraulic actuator 7, and a rod 7a is reciprocatingly driven in the state conforming to the vibration frequency of the structure I in the A and B directions. Then, since also a damping plate 6 is driven in the A and B directions, the liquid 5 stored in a tank 3 is directly allowed to generate wave motion through the tank 3 by the swing of the structure I itself, and wave motion starts in the longitudinal direction of the tank by the reciprocating shift of the damping plate 6. The wave motion pattern of the liquid 5 is controlled by the vibration suppressing controller 10 so as to offset the vibration generated on the structure I, and the vibration of the structure I is speedily attenuated.

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 relates to a vibration damping device (2) provided with a tank (3) for storing a liquid (5) in the form of forming a liquid surface (5a) in the tank. A damping means (6) is movably provided in the liquid in the central portion in the wave direction of the above, and a reciprocating drive means (7) capable of horizontally driving the damping means is connected to the damping means. Composed. 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 reciprocating driving means (7).

[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 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 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. At the center of the tank 3 in the longitudinal direction, a damping plate 6 made of a porous material such as a mesh is movably provided in the liquid 5 in the left-right direction in the figure, that is, in the longitudinal direction of the tank 3. The upper part of the damping plate 6 extends above the liquid surface 5a. A bracket 3c is provided on the upper right side of the tank 3 in the drawing, and a hydraulic actuator 7 is provided in the bracket 3c in a form in which a rod 7a is projectably driven in the directions of arrows A and B in the drawing. The upper end of the damping plate 6 is connected to the tip of the rod 7a. Also,
A vibration sensor 9 is provided on the upper surface 1a of the structure 1, and the vibration sensor 9 is connected to the vibration control device 10 to which the hydraulic actuator 7 described above is connected.

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 drives the hydraulic actuator 7 to reciprocate the rod 7a in the directions of arrows A and B in a form adapted to the vibration cycle of the structure 1. Then, the damping plate 6 is also driven in the directions of the arrows A and B, so that the liquid 5 stored in the tank 3 can directly excite waves via the tank 3 due to the shaking of the structure 1 itself, and at the same time, the damping plate 6 can be excited. By the reciprocating movement of 6, as shown by the solid line in the figure, wave motion is started in the tank longitudinal direction. Since the vibration mode of the liquid 5 is controlled by the vibration control device 10 so as to cancel the vibration generated in the structure 1, the vibration of the structure 1 is quickly attenuated. Immediately after the structure 1 starts to vibrate, the vibration sensor 9 detects the vibration, and the vibration control device 10 forcibly vibrates the liquid 5 via the hydraulic actuator 7 and the damping plate 6. It is possible to generate a wave having a predetermined amplitude in a short time rather than waiting for the liquid 5 in the tank 3 to start a natural wave due to the vibration of No. 1, and it is possible to exhibit the vibration damping effect in a short time. Become.

Further, even if the vibration of the structure 1 is small due to vibration due to a small earthquake or wind, the liquid 5 is forcibly excited by the damping plate 6, so that the vibration of the structure 1 is effectively damped. To be done. Further, when the wave of the liquid 5 exceeds a predetermined magnitude, the vibration control device 10 stops the vibration operation via the actuator 7. Then, the damping plate 6 becomes the tank 3
The liquid 5 then passes through the damping plate 6 and flows in the tank 3 in the directions of arrows A and B, and the vibration of the liquid 5 is damped by the damping plate 6 and the wave is excessive. Therefore, it is possible to prevent an obstacle to the vibration damping operation. The magnitude of the wave of the liquid 5 can be arbitrarily set by driving the damping plate 6 in the directions of arrows A and B, so that the amount of the liquid 5 in the tank 3 is at least large. It becomes possible and can exert a high damping effect.

In the above-mentioned embodiment, the tank 3 is formed in a rectangular parallelepiped shape in plan view, but the present invention uses the damping means such as the damping plate 6 as the vibrating means. Of course, the tank shape may be any shape. For example, as shown in FIG.
It is also possible to use a U-shaped tank 3. Further, the damping means may be constructed by using an orifice or the like in addition to the mesh-shaped damping plate 6.

[0012]

As described above, according to the present invention, the tank 3 in which the liquid 5 is stored so that the liquid surface 5a is formed inside.
In the vibration damping device 2 provided with, a damping plate 6 and an attenuating means such as an orifice are provided movably in the horizontal direction in the liquid at the center of the wave direction of the tank such as the arrow A and B directions. Since the reciprocating driving means such as the hydraulic actuator 7 capable of moving the damping means in the horizontal direction is connected, the liquid 5 in the tank 3 is forcibly excited by the reciprocating driving means, so that a small amount of liquid is required. However, it is possible to exert a large vibration damping effect by generating a large wave, and it is possible to reduce the amount of the liquid 5 that should be stored inside while maintaining the vibration damping effect, and to downsize the tank. This makes it possible to significantly reduce the installation area of the vibration damping device. Further, even if the vibration of the structure 1 is small, by forcibly exciting the liquid 5 by the damping means,
Since the vibration of the structure 1 can be effectively damped in a short time, it is extremely effective even in the event of wind or a small earthquake.

[Brief description of drawings]

FIG. 1 is a front view showing an 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 ... Damping device 3 ... Tank 5a ... Liquid level 6 ... Damping means (damping plate) 7 ... Reciprocating drive means (hydraulic actuator)

Claims (1)

[Claims] 1. A vibration damping device provided with a tank for storing a liquid so as to form a liquid surface therein, wherein a damping means is provided movably in the horizontal direction in the liquid at the center of the tank in the wave direction. A vibration damping device configured by connecting a reciprocating driving means capable of horizontally driving the damping means to the damping means.