JPH09177881A - Aseismic base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aseismic base isolation device capable of easily adjusting performance such as responsiveness, restoring force, by inserting a shaft body fixed to a structure through the inside of a solenoid coil fixed to the foundation of the structure and providing a magnet at a part corresponding to the inside of the solenoid coil of the shaft body. SOLUTION: Shaft bodies 2a and 2b extending in the three-dimensional direction orthogonal to each other are fixed below a foundation 11 of a bridge 10, four shaft bodies 2a extending in the horizontal direction are inserted through a horizontal base isolation solenoid coil 3a, and a shaft body 2b extending in the vertical direction is inserted through a vertical base isolation solenoid coil 3b, respectively. A permanent magnet 5 of which both magnetic poles are directed axially is embedded in a part corresponding to the inside of each of the solenoid coils 3a and 3b in the longitudinal direction of each of the shaft bodies 2a and 2b. A damper 1 is constituted from these shaft bodies 2a and 2b, the solenoid coils 3a and 3b, etc., and an aseismic base isolation device is constituted by arranging two pairs of each of such dampers 1 toward each direction so as to be orthogonal to each other three-dimensionally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation device used for various structures such as buildings, bridges, and piping for various plants.

[0002]

2. Description of the Related Art Generally, a structure is built on the ground, but since the foundation of the structure and the ground are in close contact with each other, when the ground vibrates due to an earthquake, the structure exerts an inertial force proportional to the acceleration of earthquake motion. receive. Therefore, a seismic isolation structure is adopted for the structure in order to minimize the inertial force transmitted by the earthquake. In that case, the seismic force is transmitted from the ground to the foundation to the superstructure, so that a seismic isolation device is usually provided at the foundation of the structure, which is the transmission path.

A conventional seismic isolation device is composed of, for example, an elastic spring for supporting a structure and various dampers for absorbing energy. Further, as the damper, a viscous damper such as a hydraulic damper, a steel damper that utilizes torsional deformation and bending deformation of steel, and the like are widely used.

[0004]

However, in this type of seismic isolation device, since the damper utilizes the viscosity and elasticity of its constituent elements, it is possible to adjust the speed of response, for example. It was difficult to adjust the restoring force according to the magnitude of the shaking of the structure. And in order to do that, a very complicated mechanism was needed.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a seismic isolation device capable of easily adjusting the performance such as the speed of response and the restoring force.

[0006]

In order to achieve the above object, a seismic isolation device of the present invention is provided with a solenoid coil and an axially inserted inside of the solenoid coil and fixed to a structure. Shaft member, a support member fixed to the foundation of the structure and supporting the solenoid coil, and a magnet provided in an inner portion of the solenoid coil of the shaft member and having both magnetic poles positioned in the axial direction of the solenoid coil. And a current supply source connected to the solenoid coil for supplying a current to the solenoid coil.

Further, it is preferable that the dampers are three-dimensionally arranged so that the shafts are orthogonal to each other. In addition, other components are added: (1) An earthquake sensor that detects an earthquake before the damper and generates an earthquake detection signal at that time, and an earthquake detection signal from the earthquake sensor A device equipped with a switching mechanism for supplying a current to a solenoid coil and additionally provided with a support mechanism for supporting a structure on a foundation. (2) A sensor capable of detecting the degree of shaking of the structure and the degree of shaking detected by the sensor. It is possible to employ a device having current control means for controlling the magnitude of the current flowing to the solenoid coil according to the above.

In the seismic isolation apparatus of the present invention, when a current is supplied to the solenoid coil by the current supply source, a magnetic field is generated in the solenoid coil. On the other hand, in the solenoid coil, since a magnet whose both magnetic poles are arranged in the axial direction of the solenoid coil is provided in the shaft body, the action of the generated magnetic field prevents the magnet (shaft body) from swinging in the axial direction. , A force is applied to hold the magnet in the axial center of the solenoid coil. The damper of the seismic isolation system uses this force as a restoring force for earthquake shaking.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing a basic structure of a damper portion of the seismic isolation apparatus of the present embodiment, and shows an example applied to a bridge as a structure.

The damper 1 of this seismic isolation device is composed of shafts 2a, 2
b, solenoid coils 3a and 3b, support 4a,
4b (support member), a permanent magnet 5 (magnet), and a battery 6 (current supply source). As shown in FIG. 1, such dampers 1 are three-dimensionally orthogonal to each other. , Two sets are arranged for each direction. Four supports 4a are erected on a foundation 7 constructed on the ground G, and horizontal seismic isolation solenoid coils 3a whose axial direction is oriented horizontally are fixed in the middle of each support 4a. In addition, sub-supports 4b are provided at two locations, below and above the support 4a, and the sub-supports 4b at these two locations are provided.
On the other hand, a vertical seismic isolation solenoid coil 3b whose axial direction is oriented vertically is fixed.

As shown in FIG. 2, each solenoid coil 3
A battery 6 common to all solenoid coils is connected to a and 3b. A magnetic field can be generated in the solenoid coils by passing a current through the solenoid coils 3a and 3b using the battery 6. A switch (switching means) that disconnects the circuit and connects the magnetic field generating circuit 8 that connects the solenoid coils 3a and 3b to the battery 6 is installed.

On the other hand, as shown in FIG. 1, shafts 2a and 2b which are orthogonal to each other and extend in a three-dimensional direction are fixed below the base 11 of the bridge 10. Of the shafts, four shafts 2a extending in the horizontal direction are respectively inserted in the centers of the horizontal seismic isolation solenoid coils 3a. Similarly, the shaft body 2b extending in the vertical direction is inserted through the center of the vertical direction seismic isolation solenoid coil 3b, and the lower end of the shaft body 2b is not in contact with the foundation 7.

Then, as shown in FIG. 2, each shaft 2a,
A permanent magnet 5 is embedded in a portion corresponding to the inside of each solenoid coil 3a, 3b in the longitudinal direction of 2b such that both magnetic poles are oriented in the axial direction.

In addition, between the base 11 and the base 7 of the bridge 10, a conventional general support mechanism 12 made of a hydraulic damper, laminated rubber or the like is interposed at a plurality of places.

FIG. 3 is a diagram showing the overall structure of the seismic isolation device. An earthquake sensor 13 that generates an earthquake occurrence signal when an earthquake is detected is installed at an arbitrary distance from the bridge 10, such as a coastal area. In addition, earthquake sensor 13
Should be installed in a location where it is easy to detect an earthquake. Then, the seismic sensor 13 is connected to the switch 9 in the magnetic field generation circuit 8 through a signal cable, and when the switch 9 receives the seismic generation signal sent from the seismic sensor 13, the switch 9 is turned on and the solenoid coil from the battery 6 is turned on. A current flows through 3a and 3b.

Further, the bridge 10 is provided with a sensor 15, such as a position sensor or an acceleration sensor, which can detect the degree of shaking of the bridge 10. The sensor 15 is connected to a current control device 16 including a transformer and a computer incorporated in the magnetic field generation circuit 8, and the bridge 1
In response to a signal from the sensor 15 that changes depending on the degree of swing of 0, the current control device 16 causes the solenoid coils 3a,
The configuration is such that the magnitude of the current flowing through 3b is changed.

In the seismic isolation device having the above structure, the magnetic field generating circuit 8 is normally cut off and the damper 1 does not function, so that the bridge 10 is supported by the support mechanism 12. Therefore, when an earthquake occurs, the earthquake sensor 13 immediately detects the earthquake and sends an earthquake occurrence signal to the switch 9 in the magnetic field generation circuit 8, and the operation of the switch 9 causes the magnetic field generation circuit 8 to operate.
Is connected. Then, a current flows from the battery 6 to each solenoid coil 3a, 3b, and the solenoid coil 3
The damper 1 functions by generating a magnetic field in a and 3b. That is, since the permanent magnet 5 exists in the solenoid coils 3a and 3b, the permanent magnet 5 (shafts 2a and 2b) is moved to the solenoid coil 3 by the action of the generated magnetic field.
A force that acts to hold the a and 3b in the axial center acts, and this force acts as a restoring force for the shaking of the earthquake, thereby damaging the shaking of the earthquake.

At this time, since the damper 1 is three-dimensionally arranged, it is possible to damp vibrations in both the horizontal direction and the vertical direction.

As described above, this seismic isolation device is a combination of the support mechanism 12 such as a hydraulic damper and the damper 1 according to the present invention. Normally, it depends only on the support mechanism 12 and only when an earthquake occurs the solenoid. Since it suffices to cause the damper 1 to function by passing a current through the coils 3a and 3b, it is possible to reduce power consumption.

Further, since the seismic isolation device is equipped with the sensor 15 and the current control device 16 which can detect the degree of shaking of the bridge 10, the seismic isolation device flows to the solenoid coils 3a and 3b according to the degree of shaking of the bridge 10. By changing the magnitude of the electric current, it is possible to change the magnitude of the magnetic field and thus the magnitude of the force applied to the permanent magnet 5. Therefore, the current control device 16 is properly set to control the solenoid coils 3a and 3b.
By controlling the electric current flowing through, it is possible to prevent resonance vibration and to return to a stable state faster.

That is, since the seismic isolation device of the present embodiment utilizes electromagnetic force unlike the conventional seismic isolation device, it is possible to adjust the speed of response or to adjust the structure by controlling the current. It is possible to easily adjust the restoring force according to the size of the shaking of the object.

The technical scope of the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the present embodiment, the damper 1 is used together with the conventional general support mechanism 12 such as a hydraulic damper, but the damper of the present invention may be used alone. However, in that case, since the damper at normal time must have a function of supporting the structure, the damper cannot be made to function only when an earthquake occurs, and it is necessary to always supply current to the solenoid coil. is there.

In addition to the battery, a superconducting energy storage device, other electric power storage system, or the like may be used as the current supply source to the solenoid coil, and the design of the configuration of the solenoid coil support or the like can be changed appropriately. is there. The present invention can be applied not only to bridges but also to piping and equipment of various plants and the like, and building structures such as buildings.

[0024]

As described above in detail, since the seismic isolation device of the present invention utilizes electromagnetic force unlike the conventional seismic isolation device, by controlling the current, for example, responsiveness can be improved. It is possible to easily adjust the speed or the restoring force according to the magnitude of the swing of the structure.

[Brief description of the drawings]

FIG. 1 is a diagram showing a damper portion of a seismic isolation device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a solenoid coil portion of the damper.

FIG. 3 is a diagram showing an overall configuration of the seismic isolation device.

[Explanation of symbols]

 1 Damper 2a, 2b Shaft body 3a, 3b Solenoid coil 4a, 4b Support 5 Permanent magnet (magnet) 6 Battery (current supply source) 7 Foundation 9 Switch (switching means) 10 Bridge (structure) 12 Support mechanism 13 Earthquake sensor 15 Sensor 16 Current control device

Claims (4)

[Claims] 1. A solenoid coil, a shaft body inserted axially into the solenoid coil and fixed to a structure, and a support member fixed to the foundation of the structure and supporting the solenoid coil. A magnet having both magnetic poles located in the axial direction of the solenoid coil, the magnet being provided in a portion of the shaft body corresponding to the inside of the solenoid coil; and a current supply source connected to the solenoid coil for supplying a current to the solenoid coil, A seismic isolation device comprising a damper made of 2. The seismic isolation device according to claim 1, wherein the dampers are three-dimensionally arranged so that the shafts are orthogonal to each other. 3. The seismic isolation device according to claim 1, wherein an earthquake sensor that detects an earthquake prior to the damper and generates an earthquake detection signal at that time, and the earthquake detection signal from the earthquake sensor are received. Thus, the seismic isolation device is provided with a switching unit that causes a current to flow from the current supply source to the solenoid coil, and a support mechanism that supports the structure is additionally provided on the foundation. 4. The seismic isolation device according to claim 1, wherein a sensor capable of sensing the degree of shaking of the structure, and the solenoid coil to the solenoid coil according to the degree of shaking sensed by the sensor. A seismic isolation device, comprising: a current control means for controlling the magnitude of an electric current to flow.