JPH072888Y2 - Restoring force adding device on base-isolated floor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a restoring force adding device for a seismic isolated floor.

[Prior art]

In a base-isolated floor that is supported on the ground via a seismic isolation device, a restoring force adding device that restores the floor moved by the earthquake is adopted. As such a restoring force adding device,
As shown in the figure, a support part a that is movable together with the seismic isolation floor is connected to springs b arranged from four sides. If the bearing a moves due to an earthquake,
The spring b returns the support part a to its original position.

[Problems to be solved by this device]

In the case of the restoring force adding device as described above, since three to four springs b are arranged around the support part a, it is necessary to secure a planar space and the mechanism becomes complicated. There was a problem.

In addition, there is a problem that the stiffness of the spring b is almost constant and has a specific natural period, so that resonance cannot be avoided at a certain frequency.

The present invention has been made to solve the above problems, and an object thereof is to provide a restoring force adding device for a base isolation floor which has a simple structure and can be installed even in a small space and does not cause resonance.

[Means for Solving the Problems]

The restoring force adding device for a seismic isolation floor according to the present invention uses a restoring tool composed of one coil spring. Both ends of this restoration are on the ground and seismic isolated floor,
Each of them is rotatably connected so that a predetermined angle can be changed with respect to the horizontal direction.

A coil spring and a damper may be combined as the restoration tool.

〔Example〕

Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

In the figure, reference numeral 1 denotes the ground, on which a seismic isolation floor 3 is supported via a seismic isolation device 2 placed on the ground 1. The seismic isolation device 2 may be made of laminated rubber, for example.

The restoration tool 4 is interposed between the seismic isolated floor 3 and the ground 1 as described above. In the embodiment shown in FIG. 1, a coil spring 5 is adopted as the restoring tool 4, and both ends of the coil spring 5 are on the seismic isolation floor 3.
And the fixtures 6 fixed to the ground 1, respectively. That is, spherical engaging portions 7, 7 are formed at both ends of the coil spring 5, and the engaging portions 7 are fitted into the fixtures 6 through the holes of the respective fixtures 6. The locking portion 7 does not come out of the hole of the attachment 6, and the coil spring 5 is freely rotatable by the attachment 6 within a predetermined angle range with respect to the horizontal direction.

In the restoring force adding device as described above, when the seismic isolation floor 3 moves due to an earthquake, the restoring tool 4 extends and the coil spring 5
The restoring force is added by the force of compressing, and the seismic isolation floor 3 returns to its original position. Since the coil spring 5 can freely change its angle with respect to the horizontal direction by the attachments 6 and 6, the restoring force of the spring 5 is smoothly transmitted to the seismic isolation floor 3.

FIG. 2 shows another embodiment, in which a combination of a coil spring 5 and a damper 8 is adopted as the restoration tool 4. That is, the damper 8 is fixed between the upper and lower fixing plates 9 and the coil spring 5 is attached so as to surround the outer periphery thereof. This is a case where the locking portions 7, 7 are provided on the upper and lower sides of the fixed plates 9, 9 so as to project and are respectively locked by the fixtures 6, 6.

In the case of the restoration tool 4 having such a damper 8, the swinging of the spring 5 is suppressed by the damper 8 and the original state is quickly stabilized.

[Effect of device]

The present invention has the above-mentioned structure, and the restoration tool consisting of one coil spring is interposed between the ground and the seismic isolation floor, and both ends of the restoration tool are located in the ground and the seismic isolation floor within a predetermined angle range. Since it is rotatably joined inside so that the angle can be changed in the horizontal direction, it can be installed in a small space with a simple structure and the restoring force of the seismic isolated floor can be obtained. Moreover, resonance does not occur.

Also, when the coil spring and the damper are combined to form a restoration tool, the original state is stabilized early.

[Brief description of drawings]

1 and 2 are side views of a restoring force applying device according to the present invention, FIG. 3 is a side view of the operating state thereof, and FIG. 4 is a plan view of a conventional restoring force adding device. 1 ... Ground, 2 ... Seismic isolation device, 3 ... Seismic isolation floor, 4 ... Restoration tool, 5
... Coil spring, 6 ... Fixture, 7 ... Locking part, 8 ... Damper.

Claims (2)

[Scope of utility model registration request] 1. A seismic isolation floor supported on the ground via a seismic isolation device, wherein a restoration tool composed of a single coil spring is combined between the ground and the seismic isolation floor, and the restoration tool is combined. A restoring force adding device for a seismic isolated floor, characterized in that both ends are rotatably connected to the ground and the seismic isolated floor so that they can be varied by a predetermined angle with respect to the horizontal direction. 2. The restoring force adding device for a base-isolated floor according to claim 1, wherein the restoring tool comprises a coil spring and a damper.