JP2002147529A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation device capable of restraining change of height of an upper part construction such as a building. SOLUTION: A bending ratio of a first supporting surface 9 and a second supporting surface 10 of an upper part and a lower part of a rolling member 6 is set so that fluctuation of an upper side member 4 along a vertical direction is reduced accompanied by relative movement of the upper side member 4 and a lower part side member 5 along a lateral direction. Thus, the height of the building 1 is restrained from changing accompanied by rolling.

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 interposed between, for example, a building and the foundation of the building to protect the building from rolling vibration such as an earthquake.

[0002]

2. Description of the Related Art Conventionally, in order to protect an upper structure such as a building from a rolling vibration such as an earthquake, the upper structure and a lower structure (base, foundation, etc.) provided below the upper structure. ) Tends to be installed. The seismic isolation device includes an upper member fixed to the upper structure, a lower member fixed to the lower structure, and the upper member and the lower member interposed between the upper member and the lower member. And a rolling member that rolls in accordance with the relative lateral movement of the seismic isolation device.
As disclosed in Japanese Patent Application Publication No. 3 (1993) -3, while a ball bearing as a rolling member is rotatably supported by a lower member, a concave curved surface is formed on a lower surface of an upper member, and the ball bearing is rolled within the range of the concave curved surface. Some have been moved. In this device, not only can the vibration of the lower member not be transmitted to the upper member, but also the ball bearing can be prevented from coming off from the concave curved surface due to the relationship between the concave curved surface (particularly, the surrounding rising portion) and the ball bearing. In addition to this, it is possible to make the rolling member preferable for generating a restoring force to return the rolling member to the original position (neutral position).

[0003]

However, on the other hand, in the above seismic isolation device, the upper member (particularly the surrounding rising portion) and the upper member (rolling of the ball bearing) are rolled based on the relationship between the ball bearing and the concave surface. The vertical spacing between the upper member and the lower member) will increase,
The height of superstructures, such as buildings, must also change. The present invention has been made in view of the above circumstances, and a technical problem thereof is to provide a seismic isolation device that can also suppress a change in height of an upper structure such as a building.

[0004]

According to the present invention (the invention of claim 1), an upper member fixed to an upper structure and a lower member fixed to a lower structure are provided. A seismic isolation device comprising: a side member; and a rolling member interposed between the upper member and the lower member and rolling with a relative lateral movement between the upper member and the lower member. , A first contact surface made of a spherical surface is formed on the lower surface of the upper member, and a second contact surface made of a spherical surface is formed on the upper surface of the lower member. And the distance between the first contact surface and the first contact surface gradually increases as the distance from the contact portion with the first contact surface increases along the first contact surface. A first support surface is formed so that the rolling member has a second support surface on the lower surface side.
The contact surface is brought into contact with the second contact surface so that the distance between the contact surface and the second contact surface is gradually increased as the contact surface is separated from the contact portion with the second contact surface along the second contact surface. 2 support surface is formed, and the curvature of the first and second support surfaces of the rolling member does not fluctuate in the vertical direction with the relative lateral movement of the upper member and the lower member. A configuration in which the curvature is slightly reduced as compared with the curvature of the case, and an elastic member is provided for applying a restoring force for returning the rolling member, the upper member, and the lower member to their original positions. There is. Preferred embodiments on the premise of this configuration are as described in claim 2 and the following claims.

[0005]

According to the first aspect of the present invention, the curvature of the first and second support surfaces of the rolling member is increased by the relative lateral movement of the upper member and the lower member. In comparison with the curvature when the member does not fluctuate in the vertical direction, since the curvature is slightly reduced, the fluctuation in the vertical distance between the upper member and the lower member is reduced, while the upper member and the lower member are reduced. It is possible to generate a restoring force based on the fluctuation of the vertical distance between the member and the member, thereby suppressing a change in the height of the upper structure such as a building and automatically moving the rolling member to the original position (neutral position). The return can be highly satisfied. Moreover, since the rolling member, the upper member, and the lower member are provided with an elastic member for applying a restoring force to return to the original position, the elastic member also returns to the original position (neutral position). It can be made easy.

According to the second aspect of the present invention, a restoring force for returning the rolling member to the original position is applied between the upper member and the rolling member and between the lower member and the rolling member. Since the elastic member is interposed, in addition to the restoring force based on the fluctuation of the vertical distance between the upper member and the lower member, the restoring force by the elastic member is added, and the upper part of the building or the like It is possible to make the rolling member more preferable in returning to the original position (neutral position) while suppressing a change in the height of the structure. According to the invention described in claim 3, the peripheral wall is erected on one peripheral edge of the upper member or the lower member, and the peripheral wall faces the other lateral movement region of the upper member or the lower member. Therefore, the peripheral wall portion can be used as the other stopper of the upper member or the lower member, and the relative lateral movement between the upper member and the lower member can be kept within a desired range. You can do it.

According to the invention described in claim 4, an elastic member is provided between the other peripheral portion of the upper member or the lower member and the inner peripheral portion of the peripheral wall portion. Since it is interposed so as to cover between the other peripheral portion of the member and the inner peripheral portion of the peripheral wall portion, in addition to obtaining the same operation and effect as in claim 3, the elastic member is It is possible to generate a restoring force by utilizing the dust, prevent dust from entering the storage space of the rolling member formed by the upper member and the lower member, and maintain the operation performance at a predetermined high state. Can be done. In addition, since the components such as the rolling members are housed inside and the whole is in a closed container shape, it is possible to improve the handleability. According to the invention described in claim 5, between the upper member and the rolling member, and between the lower member and the rolling member, the rolling member, the upper member, and the lower member are returned to their original positions. Claim 3 wherein an elastic member for providing a restoring force is interposed.
Or, in addition to obtaining the same operation and effect as in 4, it is possible to make the rolling member more preferable in that the rolling member is surely returned to the original position (neutral position).

According to the invention described in claims 6 to 9,
With the specific shapes of the first and second contact surfaces and the first and second support surfaces, the functions and effects of the first to fifth aspects can be specifically obtained.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a building (upper structure) such as a building or a house, and reference numeral 2 denotes a base member (lower structure) on which the building 1 is built. And the seismic isolation device 3 is interposed. An appropriate number of the seismic isolation devices 3 are interposed between the building 1 and the base member 2, and only one of them is shown in FIGS.

The seismic isolation device 3 is interposed between the upper member 4 fixed to the building 1, the lower member 5 fixed to the foundation member 2, and the upper member 4 and the lower member 5. And a rolling member 6.

A lower surface of the upper member 4 has a first contact surface 7 having a concave spherical surface, and a lower surface of the lower member 5 has a second contact surface 8 having a concave spherical surface. Is formed. The first contact surface 7 and the second contact surface 8 are each set to have a sufficiently larger area than the rolling member 6, and the first contact surface 7 and the second contact surface 8 are provided.
The center in the radial direction is the most retracted.

The rolling member 6 is sandwiched between the upper member 4 and the lower member 5, and the lateral movement of one of the upper member 4 and the lower member 5 depends on the moving direction. The movement in the opposite direction is transmitted to the other of the upper member 4 and the lower member 5 via the rolling member 6 without slipping. At this time, based on the movement of the rotation center point O of the rolling member 6, the movement amount of the other is reduced with respect to the movement amount of the one lateral direction, and the lateral swing from the one to the other is reduced. It is to be reduced (ensure seismic isolation). This will be specifically described with reference to FIG. FIG.
In order to facilitate the explanation and understanding, a simplified model in which the upper member 4 and the lower member 5 are flat plates and the rolling members 6 are spheres is shown. In FIG. 3, when the lower member 5 is moved rightward by d, the rolling member 6 is rotated counterclockwise by an arc corresponding to the d, and the rolling member 6 Based on the non-slip gripping relationship between the lower member 4 and the lower member 5, the roller 4 is rolled leftward by d (see a virtual line in FIG. 3). Accordingly, the rotation center point O of the rolling member 6 moves leftward from the original position by d, and the upper member 4 is pushed leftward by d. For this reason, when the rotation center point O of the rolling member 6 moves to a new position N with the movement of the lower member 5, the rolling member 6 is moved rightward by 2d with respect to the position N. , The upper member 4 moves leftward by d in the left direction, and is isolated.

On the upper surface of the rolling member 6,
A first support surface 9 made of a convex spherical surface is formed, and a second support surface 10 made of a convex spherical surface is formed on the lower surface of the rolling member 6.
Are formed (see FIG. 2). The first support surface 9 is
While being in contact with the contact surface 7, the distance from the contact portion with the first contact surface 7 along the first contact surface 7 gradually increases as the distance from the first contact surface 7 increases. The second support surface 10 is in contact with the second contact surface 8 and extends from the contact portion with the second contact surface 8 along the second contact surface 8. The distance between the second contact surface 8 and the second contact surface 8 gradually increases as the distance increases. The curvature of the first and second support surfaces 9 and 10 corresponds to the relative lateral movement of the upper member 4 and the lower member 5 with respect to the curvature of the first and second contact surfaces 7 and 8. Accordingly, the upper member 4 is set so as not to fluctuate in the vertical direction.

The setting for preventing the upper member 4 from moving up and down will be specifically described with reference to FIG.
FIG. 4 shows the upper member 4 for easy explanation and understanding.
FIG. 4 shows a simplified model that assumes that the rotation center point O of the rolling member 6 does not move approximately with the lateral movement of the (lower member 5), and in FIG. Direction, and the y direction indicates the horizontal direction. 4, when the lower member 5 (not shown in FIG. 4) is laterally moved, the upper member 4 is laterally moved in the opposite direction to the lower member 5 (downward in FIG. 4). When an arbitrary point A1 on the first contact surface 7 of the upper member 4 reaches a point A0 on the x-axis serving as a contact point, the height of the point A1 is changed to the first contact surface. Although the upper member 4 is lower than the point B on the first contact surface 7 where the upper member 4 is located at the neutral position (original position) based on the fact that the surface 7 is spherical, the upper member 4 is adjusted based on the curvature adjustment of the first support surface 9. , The first portion of the rolling member 6 corresponding to the
A2 on the support surface 9 (a point on the first support surface that comes into contact when the point A1 reaches the point A0 on the x-axis) is reduced, and as a result, the upper surface of the upper member 4 Height position is not changed. Of course, in this case, the curvature of the second support surface 10 is to be adjusted similarly to the second contact surface 8.

The above-mentioned simplified model will be described more specifically. In FIG. 4 showing this simplified model,
The radius of the arc of the contact surface 7 (the second contact surface 8) is R, and the rolling member 6
The distance from the rotation center point O to the arc center P of the first contact surface 7 is h, and the distance between the upper member 4 and the rolling member 6 at the neutral position is x.
The contact point on the axis is point B (R-h, 0) and the point A1 on the arc (ρ, ｛R ^2- (ρ + h) ² ｝ ^1/2 ) is moved on the x-axis by laterally moving the upper member 4. A0 point (ρ, 0)
And In such a situation, since the rotation center point O of the rolling member 6 does not move approximately, the upper member 4
Moves laterally, the point A2 (x, y) on the first support surface 9 of the rolling member 6 must reach the point A0, and the arcs A2A0 and A1B must be equal.

In this case, the angle of the arc A1B is cos
^-1 (ρ + h) / R = cos ^-1 ((x ² + y ² ) ^1/2 + h)
/ R, the arc A1B becomes the arc A1B = Rcos ^-1
((X ² + y ² ) ^1/2 + h) / R. On the other hand, arc A2
A0 _{^{is, ∫ x Rh {1+ (dy}} / dx) 2} becomes ^1/2 dx (x from integration interval Rh). Therefore, ∫ ^x _Rh ｛1+
(Dy / dx) ² ｝ ^1/2 dx = Rcos ⁻¹ ((x ² + y ² )
^The curvature of the first support surface 9 is determined based on ^1/2 + h) / R. In the above case, the rotation center point O of the rolling member 6
Does not move approximately, but of course,
If the movement of the rotation center point O of the rolling member 6 cannot be ignored, it is corrected and corrected as appropriate.

At the center of the rolling member 6 in the vertical direction,
A flange 11 is provided around the periphery of the roller 11, and a cylindrical elastic member (for example, rubber) 12 is fitted on the upper side of the rolling member 6 with the flange 11 as a reference. An elastic member (e.g., rubber) 13 is fitted. The upper end of the elastic member 12 is fixed to the periphery of the upper member 4, and the lower end of the elastic member 13 is fixed to the periphery of the lower member 5. Thereby, as shown in FIG. 2, the upper member 4 is maintained in a horizontal state above the lower member 5, and the rolling member 6, the upper member 4, and the lower member 5 are positioned at the predetermined neutral position ( These are located on the same straight line extending in the vertical direction (vertical direction) through the rotation center point O of the rolling member 6. Therefore, when a lateral load is applied from the building 1 or the foundation member 2, the rolling member 6 can easily return to the predetermined neutral position (generation of restoring force), and the upper member 4 and the lower member This is preferable in that the lateral movement of No. 5 can be ensured smoothly.

In the present embodiment, a state in which a peripheral wall portion 14 is spaced radially outward from the original position of the upper member 4 by a predetermined distance at a peripheral edge of the lower member 5 (a state in which an annular space is formed).
It is standing up integrally. The peripheral wall portion 14 faces the lateral movement region of the upper member 4, and is restricted from moving the upper member 4 in the lateral direction by a predetermined amount or more.

The upper member 4, the lower member 5, and the rolling member 6 are each made of an iron-based metal material. The reason why these members 4, 5 and 6 are made of an iron-based metal material is to increase the service life of the seismic isolation device 3. Therefore, the material of the upper member 4, the lower member 5, and the rolling member 6 is not limited to an iron-based metal material, and various materials having high rigidity such as a ceramic material and an aluminum alloy may be used. it can.

Therefore, in the seismic isolation device 3 as described above, the lower member 5 is moved from the normal state shown in FIG.
6 and 7, the rolling member 6 is rolled and the upper member 4 moves laterally in the opposite direction to the lower member 5, as shown in FIGS. At this time, the upper member (upper surface) 4 fluctuates in the vertical direction based on the curvature relationship between the first contact surface 7 and the first support surface 9 and the curvature relationship between the second contact surface 8 and the second support surface 10. Instead, the height of the building 1 is prevented from changing, and the height of the building 1 is always kept constant.

In this embodiment, the first contact surface 7
The vertical relationship between the upper member 4 and the lower member 5 does not increase due to the curvature relationship between the upper member 4 and the second support surface 10, and the curvature relationship between the second contact surface 8 and the second support surface 10. Cannot obtain a restoring force, but when rolling, the rolling member 6 rolls against the elastic force of the elastic members 12 and 13, and the repulsive force at that time becomes the restoring force. Therefore, the rolling member 6 returns to the original position (neutral position) based on the restoring force.

Further, when the upper member 4 moves laterally by a predetermined amount or more due to the roll, the upper member 4 comes into contact with the peripheral wall portion 14 and the movement of the upper member 4 by a predetermined amount or more is restricted. (See FIG. 7). For this reason, the upper member 4
The relative lateral movement between the lower member 5 and the lower member 5 is performed in a desired range where normal operation is guaranteed.

8 and 9 show a second embodiment, and FIG. 10 shows a third embodiment.
Embodiment FIG. 11 shows a fourth embodiment. In each of the embodiments, the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the second embodiment shown in FIGS. 8 and 9, an annular groove 15 is formed on the periphery of the lower surface (first contact surface 7) of the upper member 4, and an annular groove 16 is formed on the upper and lower surfaces of the flange 11.
a, 16b are respectively formed, and an annular groove 17 is formed in the peripheral portion of the upper surface (second contact surface 8) of the lower member 5. The end of the cylindrical elastic member 12 is fitted between the annular grooves 15 and 16a, and the end of the elastic member 13 is fitted between the annular grooves 16b and 17. An elastic member 18 is also interposed between the peripheral edge of the upper member 4 and the inner peripheral edge of the peripheral wall portion 14. The elastic member 18 is provided between the peripheral edge of the upper member 4 and the inner peripheral edge of the peripheral wall portion 14. It covers the annular space between the parts. Thereby, not only the elastic member 18 can secure the restoring force, but also the dust can be prevented from entering the inside of the peripheral wall portion 14 by the elastic member 18, and a high initial performance can be maintained.

In the third embodiment shown in FIG. 10, the curvatures of the first and second support surfaces 9 and 10 of the rolling members are changed by the relative lateral movement of the upper member 4 and the lower member 5. Compared to the curvature when the upper member 4 does not fluctuate in the vertical direction,
Small (large radius of curvature). That is, in FIG. 10, the curvature r of the first and second support surfaces 9 and 10 of the rolling member 6 is the curvature r when the upper member 4 does not change in the vertical direction.
The curvatures r1, r2-2, and r3-2 (FIG. 1) are slightly smaller than 1, r2-1, and r3-1 (see the phantom line in FIG. 10).
0, see the solid line). Thereby, the upper member 4 is lifted while reducing the fluctuation of the vertical distance between the upper member 4 and the lower member 5, and the vertical distance between the upper member 4 and the lower member 5 is increased. As a result, a restoring force can be generated, and the suppression of the height change of the building 1 and the automatic return of the rolling member 6 to the original position (neutral position) can be highly satisfied.

In the fourth embodiment shown in FIG. 11, the first contact surface 7 and the second contact surface 8 are convex spherical surfaces.
The first support surface 9 and the second support surface 10 are concave spherical surfaces. In the fourth embodiment, the same operation and effect as those in the first or second embodiment can be obtained. Of course, other than the above, the mode according to the first or second embodiment may be combined with the mode according to the fourth embodiment.
That is, the first contact surface 7 and the second support surface 10 are formed as concave spherical surfaces, and the second contact surface 8 and the first support surface 9 are formed as convex spherical surfaces. And the first support surface 9 are concave spherical surfaces, and the second support surface 10 and the first contact surface 7
Even if is a convex spherical surface, the same function and effect can be obtained.

Although the embodiment has been described above, the present invention is not limited to this and includes, for example, the following cases. (1) As an elastic member for generating a restoring force, a coil spring or the like is appropriately used instead of rubber. (2) A peripheral wall portion as a stopper is provided on the upper member. (3) The lower member is a lower floor member in a building, and the upper member is an upper floor member located slightly above the lower floor member (the upper floor member has a floating structure). (1) When a precision product such as a computer is disposed on the upper floor member, the precision product is protected from lateral vibration.

[Brief description of the drawings]

FIG. 1 is a plan view showing a seismic isolation device according to a first embodiment.

FIG. 2 is a longitudinal sectional view of FIG.

FIG. 3 is an explanatory diagram illustrating a seismic isolation operation of the first embodiment based on a simplified model.

FIG. 4 shows the curvature of the first contact surface (second contact surface) and the first support surface (second contact surface) when the upper member does not move vertically.
FIG. 3 is an explanatory diagram for explaining a relationship with a curvature of a support surface.

FIG. 5 is a diagram illustrating a state of the seismic isolation device in a state where the seismic isolation device is located at a neutral position before rollover.

FIG. 6 is an operation state diagram showing a state where the state of FIG. 5 changes to a state in which roll occurs.

FIG. 7 is an operation state diagram showing a continuation of FIG. 6;

FIG. 8 is a longitudinal sectional view illustrating a second embodiment.

FIG. 9 is a plan view of FIG. 8;

FIG. 10 is a longitudinal sectional view illustrating a third embodiment.

FIG. 11 is a longitudinal sectional view illustrating a fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Building (upper structure) 2 Foundation member (lower structure) 3 Seismic isolation device 4 Upper member 5 Lower member 6 Rolling member 7 1st contact surface 8 2nd contact surface 9 1st support surface 10th 2 support surface 12 elastic member 13 elastic member 14 peripheral wall 18 elastic member

Claims (9)

[Claims] 1. An upper member fixed to an upper structure, a lower member fixed to a lower structure, and the upper member and the lower member interposed between the upper member and the lower member. A rolling member that rolls with a lateral movement relative to a member, wherein a first contact surface formed of a spherical surface is formed on a lower surface of the upper member; A second contact surface made of a spherical surface is formed on the upper surface, and the first contact surface is brought into contact with the rolling member on the upper surface side, and a contact portion with the first contact surface is formed. A first support surface is formed such that the distance from the first contact surface gradually increases as the distance from the first contact surface increases, and the lower surface side of the rolling member has the second support surface. As the contact surface comes into contact with the second contact surface, the second contact surface moves away from the contact portion with the second contact surface along the second contact surface. A second support surface is formed such that a distance between the first member and the second member is gradually increased, and a curvature of the first and second support surfaces of the rolling member causes a relative lateral movement between the upper member and the lower member. In comparison with the curvature when the upper member does not fluctuate in the vertical direction,
A seismic isolation device, which is reduced in size, and is provided with an elastic member for applying a restoring force for returning the rolling member, the upper member, and the lower member to their original positions. 2. The device according to claim 1, wherein the rolling member, the upper member, and the lower member are at original positions between the upper member and the rolling member, and between the lower member and the rolling member. A seismic isolation device, wherein an elastic member for providing a restoring force for returning is interposed. 3. The upper member or the lower member according to claim 1, wherein a peripheral wall is erected on one peripheral edge of the upper member or the lower member, and the peripheral wall is the other of the upper member or the lower member. A seismic isolation device facing the lateral movement area. 4. The upper member or the lower member according to claim 3, wherein an elastic member is provided between the other peripheral edge of the upper member or the lower member and an inner peripheral edge of the peripheral wall. A seismic isolation device, which is interposed so as to cover a space between the other peripheral portion and an inner peripheral portion of the peripheral wall portion. 5. The rolling member according to claim 3, wherein the rolling member, the upper member and the lower member are disposed between the upper member and the rolling member, and between the lower member and the rolling member. A seismic isolation device characterized by comprising an elastic member for providing a restoring force for returning to a position. 6. The first contact surface and the second contact surface according to claim 1, wherein the first contact surface and the second contact surface are concave spherical surfaces. Is a convex-shaped spherical surface. 7. The first contact surface and the second support surface according to claim 1, wherein the first contact surface and the second support surface are concave spherical surfaces. Is a convex spherical surface. 8. The device according to claim 1, wherein the second contact surface and the first support surface are concave spherical surfaces, and the second support surface and the first contact surface Is a convex spherical surface. 9. The method according to claim 1, wherein the first contact surface and the second contact surface are convex spherical surfaces, and the first support surface and the second support surface Is a concave spherical surface.