JP2000161423A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a house from being moved by wind, and obtain a base isolation effect against an abrupt vibration, in a base isolation device. SOLUTION: A valve element 62 for opening or closing a bypass passage 61 by energizing a solenoid 64 is provided in a damping force variable damper 24 provided in a base isolation device. The solenoid 64 is connected to a controller 65 and a vibration sensor 68. The solenoid is not energized when vibration is not detected by the vibration sensor 68, and is energized when vibration is detected. Thus, when vibration is not generated, damping force is high and the base isolation device is substantially locked, and is unlocked when vibration is generated. Further, even when the base isolation device is substantially locked, it can operate against large vibration with high damping force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seismic isolation device,
In particular, the present invention relates to a seismic isolation device that is installed at the bottom of a structure such as a house so as to be able to perform seismic isolation operation.

[0002]

2. Description of the Related Art Various seismic isolation devices are known which provide a low-friction member between the foundation of a house and the house to make it difficult for earthquake vibrations to be transmitted to the house. With these seismic isolation devices, the lower the frictional force of the low friction means, the more difficult it is to transmit the shaking of the earthquake to the house, but if the frictional force is low, the house will move due to strong wind. There was a problem that the living comfort became poor.

In order to solve this problem, a sensor for detecting the vibration of the earthquake is provided, and when there is no vibration, the foundation and the house are connected by a pin or the like, and when the earthquake occurs, the connection between the foundation and the house is released. Things have been suggested.

[0004]

However, in the above-described conventional seismic isolation device, the foundation and the house are connected at the moment when an earthquake occurs due to a pin or the like for connecting the foundation and the house. In earthquakes that generate large vibrations early on,
There was a problem that the vibration was transmitted to the house before the connection was released. There is also a problem that the pin cannot be removed due to vibration.

Accordingly, an object of the present invention is to solve the above problems, suppress the influence of wind, and further provide an effective seismic isolation device even in the event of an earthquake in which a large shaking occurs at the beginning.

[0006]

In order to solve the above problems, the present invention has the following features. A seismic isolation device of the present invention includes a base fixed to a foundation, a support member for supporting a structure, low friction means for reducing friction between the support member and the base, and a relative position between the support member and the base. A seismic isolation device comprising: a return means for returning a position to an initial position; a damping force variable damper provided between the foundation side and the structure side; vibration detection means for detecting vibration of the ground; Damping means for setting the damping force of the variable damping force damper to a high state when the means does not detect vibration, and setting the damping force of the variable damping force damper to a low state when the vibration detecting means detects vibration; And a force control means. According to a second aspect of the present invention, in the first aspect of the present invention, the damping force variable damper increases a damping force at an extremely low operating speed at which the damper starts operating from a stopped state. And a state in which the damping force is low when the operating speed is extremely low.

Therefore, according to the present invention, when no vibration is generated on the ground, the damping force of the damping force variable damper is in a high state, so that the structure is prevented from moving due to a strong wind or the like. . Further, when vibration occurs, the damping force is set to a low state, so that a sufficient seismic isolation effect can be obtained.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of an embodiment of a seismic isolation device according to the present invention. FIG. 2 is a longitudinal sectional view taken along the line II-II in FIG. FIG. 3 is a longitudinal sectional view taken along the line III-III in FIG.

As shown in FIGS. 1 to 3, a seismic isolation device 11 generally includes a base 14 fixed to a concrete foundation 12, an upper base, a house, or the like, which is arranged to face the base 14. A support member 20 for supporting the structure (both not shown), a low friction member 22 as low friction means for reducing friction between the support member 20 and the base 14,
Four damping force variable dampers 24 (24a to 24d) for attenuating the relative speed between the support member 22 and the base 14, and return means for returning the relative position between the support member 20 and the base 14 to the initial position. Four return springs 26 (26a-2)
6d).

The base 14 is made of an iron frame 28a-2.
8d is formed in a square frame shape, and furthermore, reinforcing plates 30a to 30d arranged in a cross shape so as to intersect the intermediate portions of the respective sides of the frames 28a to 28d are connected. And the base 1 where the reinforcing plates 30a to 30d intersect
A smooth plate 32 formed in a square shape is fixed to a central portion of 4. Vibration from outside such as earthquake
Is transmitted to the flat plate 32 with low friction by the low friction member 22.

FIG. 4 shows the support member 20 and the damper 2.
FIG. 4 is a plan view showing a mounting bear of the return spring 26.

As shown in FIG. 4, the support member 20 is
The cross-sectional shape is E-shaped, and the lower plate 20a supported by the low friction member 22, the upper plate 20b to which a base or a structure is fixed, and the standing up between the lower plate 20a and the upper plate 20b. And a circular metal sliding plate 21 attached to the lower end thereof. The support member 20 is connected to the base 14.
Dampers 24 (24a to 24a)
and d) a bracket 34 (34a to 34d) to which the tip of each piston rod 25 (25a to 25d) is connected, and a return spring 26 (26a) arranged in the opposite side direction of the base 14.
To 26d), the spring retaining portion 36 (36a) to which the negative end is retained.
To 36d).

The brackets 34 (34a to 34d) are fixed in an upright state between the lower plate 20a and the upper plate 20b of the support member 20, and are 45 degrees in the X and Y directions at diagonal positions. It is mounted at an angle.

Further, a spring retaining portion 36 (36a to 36d)
The hooks 36a and 36c in the X direction are formed of holes provided in the vertical plate 20c, and the hooks 36b and 36d in the Y direction are eye nuts fixed to the upper plate 20b.

Further, a frame 28 (28a to 28d)
The brackets 35 (35a to 35d) to which the ends of the outer cylinders 27 (27a to 27d) of the damper 24 (24a to 24d) are fixed in upright positions. At the center of each side of the frame 28 (28a to 28d), a spring retaining portion 37 (37a to 37d) for retaining the other end of the return spring 26 (26a to 26d) is provided.

FIG. 5 shows the support member 20 and the low friction member 2.
FIG. 4 is a plan view showing an attached state of No. 2.

As shown in FIG. 5, a low friction member 22 having a ball bearing structure as low friction means is attached to the bottom of the column member 20. This low friction member 2
Reference numeral 2 denotes a small-diameter steel ball 40 serving as a sphere, which is accommodated in a ring-shaped resin retainer 42 serving as a sphere holding frame such that the steel balls 40 can freely roll without being restrained in their relative positions. . The inner diameter of the retainer 42 is larger than the outer diameter of the slide plate 21 on the lower end surface of the support member, and the number of the steel balls 40 is about 70 to 95% of the maximum number that can be accommodated in the retainer 42. Therefore, the friction generated between the steel balls 40 is reduced, and the low friction property is further improved.

As a result, the steel balls 40 housed in the retainer 42 can freely move on the smooth plate 32 with little resistance between the steel balls, and the support member 20 has low friction. It can roll on the smooth plate 32. Further, the ends of four return springs 44 (44a to 44d) arranged diagonally are engaged with the outer periphery of the retainer 42. Therefore, the retainer 42 includes four return springs 44.
The springs (44a to 44d) are urged to return to the balanced center.

Further, stopper members 46a for suppressing displacement of the support member 20 from four directions are provided on the reinforcing plates 30a to 30d.
To 46d are attached. The stopper members 46a to 46d hold the rubber members 48a to 48d at positions facing the periphery of the support member 20, respectively.
Reduces the impact when abutting.

Next, the structure of the damping force variable damper 24 will be described with reference to FIG. An inner cylinder 50 is provided inside the outer cylinder 27, and an annular reservoir 51 is provided between the outer cylinder 27 and the outer cylinder 27.
Is formed. Further, the outer cylinder 27 is provided with a reservoir tank 52 connected to the reservoir 51 and filled with the gas G.

At the left end of the inner cylinder 50 in the figure, a bottom valve 5 is provided.
The bottom valve 53 includes a disk 53A and a spring 53B, and forms a one-way valve that allows the flow of the oil liquid from the reservoir 51 into the inner cylinder 50 with almost no resistance. The disk 53A has a notch 5
3C is provided to allow the flow of the oil liquid from inside the inner cylinder 50 to the reservoir 51 with resistance.

The hollow piston rod 25 has a piston 5
5 are provided, and the inside of the inner cylinder 50 is divided into two chambers 56 and 57. The piston 55 is provided with disk valves 58 and 59 that generate a damping force. The disc valves 58, 59 have a configuration in which substantially no oil liquid flows when the valves are closed.

The piston rod 25 has an orifice 60
Is provided, and together with the hollow portion, constitutes a bypass passage 61 that communicates the chambers 56 and 57.

In the piston rod 25, there is provided a valve body 62 for communicating and blocking the bypass passage 61 by moving in the axial direction. The valve body 62 is urged in a valve closing direction by a spring 63 and moves in a valve opening direction when energized by a solenoid 64.

The solenoid 64 is connected by a signal line 66 to a controller 65 provided as an externally provided damping force control means. Reference numeral 67 denotes a sealing device for guiding the signal line 66 to the outside.

The controller 65 is connected to a vibration sensor 68 provided on the ground side as vibration detection means. The controller 65 and the vibration sensor 68
May be provided not for each damper, but for one structure.

An example of the vibration sensor 68 will be described with reference to FIG.

A weight 71 is provided at the upper end of a rod 70 extending vertically from the ground, and the rod 70 is curved by the vibration of the ground so that the weight 71 swings. Around it is provided a case 72 for preventing the influence of wind from the outside. A photoinstructor 73 is provided inside the case 72 so that the weight 71 blocks light when the rod 70 is in a vertical state.
The photo instructor 73 is connected to the controller 65 described above. In addition, this vibration sensor 68
By preparing one with several kinds of natural frequencies,
Vibration can be captured with higher sensitivity.

Next, the operation of the present embodiment will be described.

When there is no vibration on the ground, the vibration sensor 6
The 8 photo instructor 73 is blocked by the weight 71 and is in an off state. In this state, the controller 65 does not energize the solenoid 64 and
Is in a closed state.

The damping force characteristic of the damper 24 at this time is as indicated by the broken line in FIG. For this reason, even when the structure is exposed to strong wind, the damping force at the extremely low operating speed at which the damper starts operating from the operation stop state is high, so that the damper 24 is substantially locked, and the wind is affected by the wind. The structure is prevented from moving. Next, when the ground vibrates due to the earthquake, the weight 71 moves, and the vibration sensor 68
The photo instructor 73 is turned on. In this state, the controller 65 starts energizing the solenoid 64, and the bypass passage 61 of the damper 24 is in a connected state. The power supply to the solenoid 64 is cut off a predetermined time after the power supply to the photoinstructor 73 is turned off.

At this time, the damping force characteristic of the damper 24 is as indicated by the solid line in FIG. For this reason, the damping force at an extremely low operating speed at which the damper starts operating from the operation stop state is reduced, and the lock of the damper 24 is substantially released, and the structure can be moved.

In this state, the base 14 and the support member 20
, The horizontal movement of the ground is transmitted to the support member 20 only by the resistance of the base 14 and the support member 20. And this relative motion is the damper 2
4 (24a to 24d). Further, at the time when the vibration is finished, the relative position between the base 14 and the support member 20 is always returned to substantially the center of the base 14 by the return springs 26 (26a to 26d).

As described above, the seismic isolation device of this embodiment substantially locks the operation of the device when there is no vibration on the ground, prevents the structure from being moved by the wind, and
When an earthquake occurs, the lock can be released immediately to obtain the seismic isolation effect.

When suddenly large vibrations are generated, even before the solenoid 64 of the damping force variable damper 24 is energized, the damping force is increased even in a substantially locked state. Therefore, for a large force, the disk valves 58 and 59 of the damper 24 are opened, so that the seismic isolation device can be operated. Therefore, even in the case where a sudden large shake around the epicenter occurs, the seismic isolation effect can be obtained even before the variable control of the damping force is completed.

In the above-described embodiment, an example in which the photoinstructor 73 is used as the vibration sensor 68 has been described. However, the present invention is not limited to this. Anything is fine.

[0038]

According to the present invention, the damping force variable damper provided between the foundation side and the structure side, the vibration detecting means for detecting the vibration of the ground, and the vibration detecting means detect the vibration. And damping force control means for setting the damping force of the damping force variable damper to a high state when there is no vibration and for setting the damping force of the damping force variable damper to a low state when the vibration detecting means detects vibration. By using the seismic isolation device, when there is no vibration, high damping force is used, so that the structure is prevented from moving due to the influence of the wind.
Since the damping force is low, the effect of seismic isolation can be obtained.
In addition, even if switching of the damping force variable damper cannot be performed in time for a sudden vibration, the damper can be operated with a high damping force, so that a seismic isolation effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of a seismic isolation device according to the present invention.

FIG. 2 is a longitudinal sectional view taken along the line II-II in FIG.

FIG. 3 is a longitudinal sectional view taken along line III-III in FIG.

FIG. 4 is a plan view showing a mounting state of a support member 20, a damper 24, and a return spring 26.

FIG. 5 is a plan view showing a mounting state of a support member 20 and a low friction member 22.

FIG. 6 is a cross-sectional view of the damping force variable damper 24 in FIG.

FIG. 7 is a diagram showing a vibration sensor 68 in FIG. 6;

8 is a diagram showing a damping force characteristic of the damping force variable damper 24 shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 12 base 14 base 20 support member 21 slide plate 22 low friction member (low friction means) 24 variable damping force damper 26 return spring (return means) 40 steel ball (sphere) 65 controller (damping force control means) 68 vibration sensor (vibration) Detection means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) E04B 1/36 E04B 1/36 N E04H 9/02 331 E04H 9/02 331D F16F 15/067 F16F 15/06 H (72) Inventor Junji Hashimoto 1116 Koizono, Ayase-shi, Kanagawa Prefecture Tokiko Corporation Sagami Plant (72) Inventor Yuki Takagi 1116, Koizono Ayase-shi, Kanagawa Prefecture Tokiko Corporation Sagami Plant F-term (reference) 2D046 DA12 3J048 AA02 AA03 AC01 AC04 BC02 BE04 BE15 BG02 CB21 DA05 EA38

Claims (2)

[Claims] 1. A base fixed to a foundation, a support member for supporting a structure, low friction means for reducing friction between the support member and the base, and an initial position of the support member relative to the base. A seismic isolation device comprising: a return means for returning to a position; a damping force variable damper provided between the foundation side and the structure side; a vibration detection means for detecting ground vibration; and the vibration detection means Damping force control means for setting the damping force of the variable damping force damper to a high state when no vibration is detected, and for setting the damping force of the variable damping force variable damper to a low state when the vibration detecting means detects vibration. A seismic isolation device characterized by the following. 2. The damping force variable damper according to claim 1, wherein the damper has a high damping force for increasing the damping force at an extremely low operating speed at which the damper starts operating from a stopped state, and a damping force at an extremely low operating speed. 2. The seismic isolation device according to claim 1, further comprising: a state in which the damping force is reduced to reduce the vibration.