JPH1026136A - Base isolation device for light load - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation device which is high in load supporting capacity and is capable of freely setting horizontal spring performance and a damping factor. SOLUTION: The device is provided by arranging linear bearings in which resistance is imparted to the movings of second members 11 along long first members 10 by preload applied to the bearing by being orthogonally crossed in the vertical directions and with a vibration damping mechanism formed by mutually integrating upper and lower second members 11, 11 (first members 10 each other) and sping elements for moving and restoring the second members 11 constituting the vibration damping mechanism in the middle of the first members 10. The first members 10 (the second members 11) on the upper side and the first members 10 (second members 11) on the lower side are mounted on a structure and a ground side base body, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light-load seismic isolation device.

[0002]

2. Description of the Related Art As a seismic isolation device, for example, there is a device in which a rubber plate and a metal plate are alternately laminated and fixed (hereinafter, this portion is referred to as an isolator) and mounting plates are fixed to upper and lower portions thereof. . This device is installed such that the upper mounting plate is mounted on the structure, and the lower mounting plate is mounted on the ground-side foundation.

[0003] Therefore, when a horizontal vibration is generated on the ground side, the isolator portion is sheared and deformed, whereby the vibration energy transmitted from the ground side foundation to the structure side is absorbed.

However, when the seismic isolation device having the above configuration is used for a lightly-loaded structure, there is a problem that the vibration energy is not sufficiently absorbed due to the large shear spring constant of the isolator portion. If the pressure receiving area is reduced (lengthened) to reduce the shear spring constant of the portion, a buckling phenomenon occurs, and there is a problem that the function as the device is not fulfilled at all.

[0005] As a seismic isolation device for light loads, FIG.
A so-called rocking ball type in which a hard ball 91 is interposed between upper and lower bowl-shaped bodies 90 as shown in FIG. Has not been reached.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a light-weight seismic isolation device having a high load-bearing capacity and capable of freely setting a horizontal spring performance and a damping rate.

[0007]

According to a first aspect of the present invention, a light-load seismic isolation device is provided with resistance to movement of a second member along a long first member by pressurization applied to a bearing. A linear motion bearing is vertically arranged in a vertical direction, and a vibration damping mechanism formed by integrating upper and lower second members with each other, and a second member constituting the vibration damping mechanism is a first member.
A spring element for returning to the middle of the member, wherein the upper first member is attached to the structure, and the lower first member is attached to the ground-side foundation.

According to a second aspect of the present invention, there is provided a light-load seismic isolation device, comprising: a linear motion bearing provided with resistance to movement of a second member along a long first member by pressurization applied to the bearing; In the direction perpendicular to each other and the first
A vibration damping mechanism formed integrally with the members, and a spring element for moving and returning the second member constituting the vibration damping mechanism to the middle of the first member, wherein the upper second member is a structure The lower second member is attached to the ground-side foundation.

The installation method of the above-described light-load seismic isolation device and the function of this device will be clarified in the section of the embodiment of the invention.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings.

FIG. 1 shows a lightweight structure A and a ground-side foundation B
And four seismic isolation devices C are provided between the two. The seismic isolation device C includes a vibration damping mechanism 1 and a spring element 2. Hereinafter, the vibration damping mechanism 1 and the spring element 2 will be described in detail. [About the vibration damping mechanism 1] As shown in FIG. 2, the vibration damping mechanism 1
A linear bearing in which resistance is given to the movement of the second member 11 along the member 10 is arranged so as to be orthogonal to each other in the vertical direction, and the upper and lower second members 11 are integrally formed with each other. As shown in FIGS. 1 and 3, the upper first member 10 is attached to the structure A, and the lower first member 10 is attached to the ground-side foundation B. Here, the first and second members are both made of hard metal.

As shown in FIG. 4, a large number of balls 12 enabling smooth relative movement between the first member 10 and the second member 11 are interposed between the first member 10 and the second member 11, as shown in FIG. At the intervening position, R-shaped grooves 10a and 11a are formed so as to sandwich the ball 12, and a circular path 13 having a slightly larger diameter than the ball 12 is formed in the second member 11 to circulate the ball 12. Is formed.

In the vibration damping mechanism 1, it is possible to freely set the preload applied to the bearing by changing the dimensional tolerance such as the depth of the grooves 10a and 11a in the manufacturing process and changing the size of the ball. And the damping performance can be set freely. Therefore, as shown in FIG. 5 in the section of the prior art, it is possible to reduce the influence of wind load or the like.

The load of the structure A is very large because the load is supported by the vibration damping mechanism 1 made of hard metal. [Regarding the Spring Element 2] As shown in FIG. 1, the spring element 2 moves the second member 11 constituting the vibration damping mechanism 1 to the middle of the first member 10 and returns the same. The other end of the object A is attached to the ground-side foundation B.

The spring element 2 is not limited to a coil spring, but may be a cylindrical rubber body or an isolator. [Other Embodiment 1] The second members 11, 11
May be constituted by one block in advance in the manufacturing process. [Other Embodiment 2] Instead of the above embodiment, a linear motion bearing in which resistance is given to the movement of the second member 11 along the long first member 10 by pressurization applied to the bearing is used in the vertical direction. And a vibration damping mechanism 1 formed integrally with the upper and lower first members 10, 10 and a second member 11 constituting the vibration damping mechanism 1.
And a spring element 2 that returns to the middle position of the first member. In this case, the upper second member 1
1 is a structure A, and a lower second member 10 is a ground-side foundation B.
, Respectively. [Other Embodiment 3] A coil spring in which the spring element 2 is arranged in a horizontal state, one end of which is a first member, and the other end of which is a second spring
It can be configured to be attached to a member.

[0016]

As is clear from the description of the embodiments of the present invention, a lightweight seismic isolation device having a high load-bearing capacity and capable of freely setting a horizontal spring performance and a damping rate can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a lightweight seismic isolation device according to an embodiment of the present invention is arranged.

FIG. 2 is a perspective view showing a vibration damping mechanism in the lightweight seismic isolation device.

FIG. 3 is a front view showing a state where the vibration damping mechanism is installed between a structure and a ground-side foundation.

FIG. 4 is a partial cross-sectional view of the vibration damping mechanism.

FIG. 5 is a front view of a prior art vibration damping mechanism.

[Explanation of symbols]

 A Structure B Ground-side foundation 1 Vibration damping mechanism 2 Spring element 10 First member 11 Second member

Claims (5)

[Claims] 1. A linear motion bearing in which resistance to movement of a second member along a long first member is given by pressurization applied to the bearing, and the linear motion bearing is arranged orthogonally in the vertical direction, and the upper and lower second members are arranged. A vibration damping mechanism formed integrally with each other; and a spring element for moving and returning a second member constituting the vibration damping mechanism to a middle position of the first member. A light-weight seismic isolation device, wherein the lower first member is attached to the ground-side foundation. 2. A linear bearing in which resistance to movement of a second member along a long first member is imparted by pressurization applied to the bearing, wherein the linear motion bearing is arranged orthogonally in the vertical direction, and the first and second vertical members are arranged vertically. A vibration damping mechanism formed integrally with each other, and a spring element for moving and returning a second member constituting the vibration damping mechanism to a middle position of the first member; A light-weight seismic isolation device, wherein the lower second member is attached to the ground-side foundation. 3. The spring element according to claim 1, wherein the spring element is a horizontal spring and is provided separately from the vibration damping mechanism, and one end is attached to the structure, and the other end is attached to the ground side. Light load seismic isolation device. 4. The spring element is a horizontal spring, one end of which is a first spring.
The light-load seismic isolation device according to claim 1 or 2, wherein the other end of the member is attached to the second member. 5. The light-load seismic isolation device according to claim 1, wherein the linear bearing is a circulation type.