JPH06193308A - Variable damping seismic isolation device - Google Patents

Abstract

(57) [Summary] [Structure] A laminated rubber 3 having one end fixed to the base 2 and an upper building 4 installed on the other end and a damper 9 are provided, and the damper 9 is fixed to the base 2. With electrode 16 inside
A casing 13 in which is provided, a wire 6 stretched around the upper building 4, and a rotating member 21 around which the wire 6 is wound and which is rotatably supported by the casing 13 and provided with an electrode 22 on the outside. , Inside the casing 13,
Electrorheological fluid 23 whose viscosity is controlled by the applied voltage 23
Is enclosed. [Effect] Rotational resistance corresponding to the viscosity of the electrorheological fluid 23 is applied to the rotating member 21, so that the electrodes 16, 22
By changing the voltage applied in the interim, that is, the voltage applied to the electrorheological fluid 23, the rotation resistance of the rotating member 21, that is, the damping constant and the natural period of the seismic isolation device are changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable damping seismic isolation device capable of performing seismic isolation of an upper building and changing its damping characteristics.

[0002]

2. Description of the Related Art Conventionally, as a seismic isolation device for seismic isolation of an upper building, a laminated rubber having one end fixed to a foundation and the upper building installed on the other end, and a rubber between the foundation and the upper building. What has a damper provided is used.

[0003]

However, the above-mentioned seismic isolation device has a constant damping characteristic of the damper, and since it copes with a large-scale earthquake, the damper has rigidity at a small amplitude, and the upper part at a small earthquake. There was a problem that the seismic isolation effect was reduced by shortening the relatively long natural period of the building. Further, in order to realize a long natural period obtained by the laminated rubber, it is generally necessary for the damper to allow a large displacement (stroke).

An object of the present invention is to provide a variable damping seismic isolation device which can always obtain optimum damping performance regardless of the magnitude of an earthquake and can cope with a large stroke.

[0005]

In order to achieve the above object, a variable damping seismic isolation device of the present invention comprises a laminated rubber in which one end side is fixed to a foundation part and an upper building is installed at the other end side, and the foundation. Part and the damper provided between the upper building, the damper is fixed to the base portion and a casing provided with an electrode on the inner peripheral side, and the damper is stretched to the upper building A wire and a rotating member rotatably supported by the casing and rotatably supported by the casing and provided with an electrode on the outer peripheral side of a portion located in the casing, wherein the casing has a viscosity depending on an applied voltage. It is characterized by enclosing an electrorheological fluid whose temperature is controlled.

[0006]

According to the variable damping seismic isolation device of the present invention, when the upper building vibrates with respect to the foundation, the laminated rubber is deformed and the wire stretched over the upper building moves together with the upper building. As a result, the rotating member wound with the wire rotates. Here, since the electrorheological fluid is enclosed in the casing that supports the rotating member, the rotating member has a rotational resistance corresponding to the viscosity of the electrorheological fluid. Therefore, a laminated rubber with a low initial rigidity is used, and the voltage applied between the electrode provided on the inner peripheral side of the casing and the electrode provided on the outer peripheral side of the rotating member, that is, the voltage applied to the electrorheological fluid. By changing the, the rotational resistance of the rotating member, that is, the damping constant and the natural period of the damper change, so that optimum damping performance can always be obtained regardless of the scale of the earthquake. Moreover, since a rotary type damper is used, a large stroke can be accommodated.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A variable damping seismic isolation device according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a variable damping seismic isolation device 1 according to the present embodiment. The variable damping seismic isolation device 1 has one end side fixedly installed at a plurality of predetermined positions on a base portion 2 and has a low initial rigidity. It has a rubber 3, and an upper building 4 is installed on the other end side of the laminated rubber 3. As the laminated rubber, there are natural rubber-based or silicon rubber-based laminated rubbers, but the types thereof are not particularly limited.

A plurality of wire supporting portions 5 are provided in predetermined areas on the lower surface of the upper building 4 at predetermined positions that do not interfere with the laminated rubber 3 with respect to the movement of the upper building 4. As shown in FIG. 2, for example, as shown in FIG.
A wire 6 made of high-tensile steel is stretched so that those adjacent to each other along the respective sides form an angle of 90 ° with each other.

Here, as shown in FIG. 3, each wire supporting portion 5 extends on the lower surface 7 side of the upper building 4 along the lower surface 7 and in a direction substantially orthogonal to the extending direction of the supporting wire 6. It is supported by the guide rail 8 fitted so as to be movable along its extending direction. This allows
The wire 6 moves together with the upper building 4 in a direction along the extending direction of the wire when wound around a damper body 9 described later, and does not affect the movement of the upper building 4 in a direction perpendicular to the moving direction. (That is, no unreasonable force is applied when the upper building 4 moves in this direction) The state becomes free.

A damper body 9 which constitutes a damper together with the wire 6 is provided on the base portion 2 between the pair of wire supporting portions 5, and the damper body 9 is shown in FIGS. 4 and 5.
As shown in (1), it is provided with a casing 13 that is composed of a cylindrical portion 10 and an upper closing portion 11 that closes the upper end of the cylindrical portion 10 and that is fixedly installed on the foundation portion 2.
The upper closed portion 11 of the casing 13 includes a cylindrical portion 10
The support hole 14 is formed around the axis of
A support hole 15 is also formed in the base portion 2 coaxially with the support hole 14. In addition, the electrode 16 that can be energized from the outside is fixed to the entire inner circumference of the cylindrical portion 10.

The casing 13 is rotatably supported in the support hole 14 of the upper closed portion 11 and is also casing 1.
3, a wire 6 is wound around a tip end portion of the wire 6, and the winding portion of the wire 6 is embossed for the purpose of preventing slippage, and an inner peripheral surface and a bottom surface of the support hole 15 of the base portion 2. Slide bearing 17 installed in
a lower support shaft portion 19 rotatably supported by a and 17b (or bearings), and a slide bearing 1 provided between the support shaft portions 19 and provided outside the support hole 15.
7c (or bearing) supported large diameter main shaft 2
There is provided a rotating member 21 made of steel and having a columnar shape with a step. In addition, an electrode 22 that can be energized from the outside is fixed to the outer peripheral surface of the main shaft portion 20 of the rotating member 21 so as to face the electrode 16, and between the electrode 22 and the electrode 16. An annular constant gap is formed.

An electrorheological fluid 23, the viscosity of which can be controlled to be changed by changing the applied voltage (that is, the electric field strength), is enclosed in the gap between the electrode 16 of the casing 13 and the electrode 22 of the rotating member 21. . Although not shown, the damper body 9 has a seal structure that prevents the electrorheological fluid from leaking to the outside of the damper body 9 through the support holes 14 and 15 from the gap between the electrodes 16 and 22. ing. Further, the electrodes 16 and 22 are subjected to a predetermined insulation treatment so that they are not energized except through the electrorheological fluid 23.

According to the variable damping seismic isolation device 1 of the present embodiment having the above-mentioned structure, when an earthquake or the like occurs and the upper building 4 vibrates with respect to the foundation portion 2, the laminated rubber 3 having a small initial rigidity is obtained.
When the wire 6 is deformed, one of the wires 6 stretched over the upper building 4 along the vibration direction of the upper building 4 moves together with the upper building 4, whereby the damper around which the wire 6 is wound is wound. Main shaft 2 of rotating member 21 of main body 9
0 will rotate in the casing 13. here,
Since the electrorheological fluid 23 is enclosed in the casing 13 that supports the rotating member 21, this electrorheological fluid 23
The rotational resistance corresponding to the viscosity of the rotating member 21 is applied to the rotating member 21. Therefore, the voltage applied between the electrode 16 provided inside the casing 13 and the electrode 22 provided outside the rotating member 21, that is, the electric By changing the voltage applied to the viscous fluid 23, the rotation resistance of the rotating member 21, that is, the damping constant and the natural period of the seismic isolation device 1 change.

Although not shown, a sensor for detecting the vibration state of the foundation 2 and the upper building 4 and an optimal damping constant are determined from information from this sensor to determine both electrodes 1
By providing a control device that controls the voltage applied to the electro-rheological fluid 23 between 6, 6 and 22, the natural period of the variable damping seismic isolation device 1 and Since the damping constant is controlled, the optimum control force can always be given regardless of the scale of the earthquake. Therefore, it is possible to exert the optimum seismic isolation effect from a low displacement level to a large displacement. In this case, since the equivalent viscosity of the electrorheological fluid 23 changes instantaneously by changing the electric field strength, no response delay occurs. Moreover, since the damper main body 9 is of the rotary type, it is possible to cope with a large stroke of the upper building 4.

The casing 13 and the rotating member 21
When the electrodes are formed of a conductive material, it is not necessary to fix the electrodes to each of them, and a voltage may be applied directly to the casing 13 and the rotating member 21 (in this case, the casing 13 and the rotating member 21 serve as electrodes). Also in this case, the casing 13 and the rotating member 21 are subjected to a predetermined insulation treatment so that they are not energized except through the electrorheological fluid 23.

When the resistance force of the electrorheological fluid is increased, the main shaft portion of the rotating member is formed of a plurality of disc-shaped plates made of a conductive material, and the inside of the casing is also made of a plurality of conductive materials. The disc-shaped plates are arranged and fixed so as to alternate with the plates of the rotary member, or the main shaft portion of the rotary member is made into a disc shape, and a plurality of cylindrical plates made of a conductive material and having different diameters are attached to the main shaft portion. It may be fixed concentrically along the axial direction, and a plurality of cylindrical plates made of a conductive material and having different diameters may be arranged and fixed along the axial direction so as to alternate with the plates of the rotating member along the axial direction. It is possible.

[0017]

As described above in detail, according to the variable damping seismic isolation device of the present invention, the laminated rubber having a small initial rigidity and the damper are combined, and the damper is provided with the electrode provided on the inner peripheral side of the casing. By changing the voltage applied to the electrode provided on the outer peripheral side of the rotating member, that is, the voltage applied to the electrorheological fluid, the rotating resistance of the rotating member, that is, the damping constant and the natural period of the damper will change. The optimum damping performance can always be obtained regardless of the scale of the earthquake. Therefore, it is possible to exert the optimum seismic isolation effect from a low displacement level to a large displacement. Moreover, since a rotary type damper is used, a large stroke can be accommodated.

[Brief description of drawings]

FIG. 1 is a front view schematically showing a variable damping seismic isolation device according to an embodiment of the present invention.

FIG. 2 is a plan view of a damper of a variable damping seismic isolation device according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a wire supporting portion of a variable damping seismic isolation device according to an embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view showing a damper of a variable damping seismic isolation device according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view showing a damper of a variable damping seismic isolation device according to an embodiment of the present invention.

[Explanation of symbols]

 1 Variable damping seismic isolation device 2 Foundation part 3 Laminated rubber 4 Upper building 6 Wire 9 Damper body 13 Casing 16, 22 Electrode 21 Rotating member 23 Electro-rheological fluid

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiko Maebayashi 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Yoshihiro Kurida 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Shoji Hayashi 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd.

Claims (1)

[Claims] 1. A laminated rubber having one end fixed to a foundation and an upper building installed at the other end, and a damper provided between the foundation and the upper building, wherein the damper comprises: A casing fixed to the base portion and provided with an electrode on the inner peripheral side, a wire stretched over the upper building, a wire wound around the casing and rotatably supported by the casing, and positioned inside the casing. A variable damping seismic isolation device characterized in that it has a rotating member provided with an electrode on the outer peripheral side of a portion to be filled, and an electrorheological fluid whose viscosity is controlled by an applied voltage is enclosed in the casing. .