JP3594403B2 - Seismic isolation device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a seismic isolation device that is installed in a structure such as a high-rise building or a general house to avoid damage or destruction when an earthquake occurs.
[0002]
[Prior art]
Conventional structures are built directly on foundations embedded in the ground, and are constructed so that vibrations from earthquakes are directly transmitted to the above structures. Occasionally, damage, destruction or collapse occurs.
[0003]
On the other hand, in order to minimize the damage caused by such an earthquake, as shown in FIG. 6, a lower conical pan 24 and an upper conical pan 25 sandwiching a ball 23 between the foundation 21 and the structure 22. There is proposed a seismic isolation device in which a plurality of sets are interposed and a ball 23 is rolled on a lower conical pan 24 which swings when an earthquake occurs to suppress the transmission of the earthquake to the structure 22 itself.
[0004]
In this seismic isolation device, as shown in FIG. 7, the inclination angles of the conical surfaces of the lower conical pan 24 and the upper conical pan 25 are θ (rad), and the radius of the ball 23 is R (cm). The amount of horizontal movement of the ball 23 in the upper and lower surfaces of the trays 24 and 25 in the upper and lower surfaces is X (cm), the amount of movement of the ball 23 in the slope direction is L (cm), and the rotation angle of the ball 23 is α ( Assuming rad), if the one-sided horizontal movement amount is X under the condition that slippage between the ball 23 and each of the receiving trays 24 and 25 is ignored, the slope direction movement amount L is L = X / cos θ.
[0005]
Since the amount of movement L in the slope direction is equal to the circumferential distance of the ball 23, the ball rotation angle is L = R · α, and α = L / R = X / Rcos θ.
[0006]
Therefore, since the rotation angle α varies depending on the radius R of the ball 23 and the conical surface inclination angle θ, the distance LB between the balls 23 and 24 changes with respect to the distance LP between the adjacent trays 24 and 25. There is.
[0007]
[Problems to be solved by the invention]
Since the conventional seismic isolation device is configured as described above, the rotation angle α of the ball 23 changes depending on the radius R of the ball 23 and the conical surface inclination angle θ of each of the trays 24, 25, and the respective trays 24, 25 However, when a plurality of sets are arranged, the rotation angle α differs due to the manufacturing error of the R value and θ value, and the balls 23, There is a problem that the distance between the members 23 changes during operation, that is, the ball 23 does not return to the home position, and the seismic isolation operation cannot be performed normally.
[0008]
In addition, since the sides of the trays 24 and 25 are open, rain, dust, and dust enter between the balls 23 and the trays 24 and 25, and the rolling of the balls 23 is hindered. was there.
[0009]
SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. In addition to preventing the positions of a plurality of balls from changing, the rolling power of the balls can be rapidly attenuated, and the rolling of the balls due to dust is further improved. An object is to provide a seismic isolation device that can avoid obstacles.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the seismic isolation device according to the first aspect of the present invention is arranged at a plurality of locations between a foundation or a base structure and the seismic isolation target, and the seismic isolation target is damaged when an earthquake occurs. In a seismic isolation device for avoiding destruction, an upper conical pan and a lower conical pan disposed respectively at four corners of a square between a foundation or a base structure and an object to be isolated, and an upper conical pan A ball that is rollably sandwiched between the ball and the lower conical pan, a cylindrical ball housing that surrounds the horizontal periphery of the ball and holds the ball so that it can roll, and attached to the outer periphery of the ball housing. And a connecting member connected to the holding band and extending in the primary direction and the secondary direction, and the connecting members connect the pressing bands adjacent to each other in the primary direction and the secondary direction. It is those that.
[0011]
Further, in the seismic isolation device according to the second aspect of the present invention, the ball housing is provided with a friction member that comes into frictional contact with the ball or a part of the lower conical pan.
[0012]
According to a third aspect of the present invention, there is provided the seismic isolation device, wherein a cover for sealing the storage portion of the ball is provided between the lower conical pan and the upper conical pan and the ball housing.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 are enlarged cross-sectional views showing a main part of a seismic isolation device of the present invention. In FIG. This is a lower conical tray mounted and fixed on a foundation or a substructure, and on the upper surface thereof, for example, a conical inclined surface 1a having an inclination angle of 1 degree is formed.
[0014]
Reference numeral 2 denotes an upper conical saucer fixed to the lower surface of a structure such as a house or a building, and the lower surface of which is formed with a conical inclined surface 2a having an inclination angle of 1 degree, for example, as described above. I have.
[0015]
A ball 3 is interposed between the conical inclined surface 1a of the lower conical saucer 1 and the conical inclined surface 2a of the upper conical saucer 2 so as to roll freely.
[0016]
Reference numeral 4 denotes a cylindrical ball housing which surrounds the horizontal periphery of the ball 3 and holds the ball 3 so as to roll freely. The ball housing 4 is composed of the lower conical tray 1 and the upper conical tray. Between the two, it can be moved horizontally.
[0017]
Covers 5 and 6 are attached to the upper and lower portions of the outer periphery of the ball housing 4 so that the tips are in elastic contact with the lower conical saucer 1 and the upper conical saucer 2. The inside of the storage section S for storing the ball 3 can be hermetically sealed.
[0018]
The lower conical pan 1, the upper conical pan 2, the ball 3, the ball housing 4, and the covers 5, 6 constitute the seismic isolation device M.
[0019]
Further, reference numeral 7 denotes a friction material as a friction member attached to the inner peripheral surface of the upper part of the ball housing 4, a part of which comes into contact with a part of the ball 3 by its own weight, and A predetermined frictional resistance is generated.
[0020]
Reference numeral 8 denotes a pressing band attached to the outer periphery of the central portion of the ball housing 4 to hold the ball housing 4. The pressing band 8 has the same configuration as the above as shown in FIGS. Each end of a connecting rod 9 as a connecting member such as a turnbuckle bolt for connecting to another set of holding bands 8 constituting the seismic isolation device is fixed.
[0021]
In this embodiment, four seismic isolation devices M arranged at four corners of a square are connected by four connecting rods 9 via respective holding bands 8.
That is, as shown in FIG. 3, each seismic isolation device M is disposed at four corners of a planar square, and is connected to the primary direction (front-rear direction in FIG. 3) connected to the holding band 8 of each seismic isolation device M. Pressing bands 8, 8 adjacent to each other in the primary direction and the secondary direction are connected by two connecting rods 9, 9 extending in the next direction (left-right direction in FIG. 3).
[0022]
In addition, 10 is a foundation (or foundation structure), and 11 is a seismic isolation target of a ground structure.
[0023]
Next, the operation will be described. Assuming that an earthquake has occurred, the foundation 10 swings, and accordingly, the ball 3 rolls on the conical inclined surface 1 a on the swinging lower conical tray 1. Move.
[0024]
For this reason, a relative displacement occurs between the lower conical saucer 1 and the upper conical saucer 2, for example, as shown in FIG. 4, and the movement of the foundation 10 is transferred to the seismic isolation target 11, which is a ground structure. Make it harder to communicate.
[0025]
The magnitude X0 of the relative displacement is twice as large as the displacement X of the ball 3 (X0 = 2X).
[0026]
On the other hand, the rolling of the balls 3 is performed in the ball housing 4, and since the four ball housings 4 are connected to each other by the connecting rods 9, the balls 3 in each of the ball housings 4 can roll independently. Instead, each ball 3 rolls in the same direction and by the same amount.
[0027]
Therefore, the position of the ball 3 on one lower conical tray 1 does not differ from the position of the ball 3 on the other lower conical tray 1.
[0028]
In addition, since the balls 3 of each seismic isolation device M do not individually move freely, and the degree of displacement between the ball 3 for each seismic isolation device M and the lower conical saucer 1 becomes equal, the seismic isolation operation is abnormal. Avoidance becomes possible, and after the earthquake stops, each ball 3 automatically returns to its normal original position.
[0029]
Further, when each of the balls 3 rolls as described above, the friction material 7 attached to the ball housing 4 is in frictional contact with a part of the ball 3 by its own weight, so that its rolling power (rolling inertia) is reduced. The ball 3 is quickly attenuated, and the operation of the ball 3 is stabilized in the vibration direction.
[0030]
As shown in FIG. 1, covers 5 and 6 for sealing the storage portion S of the ball 3 are provided between the ball housing 4 and the lower conical saucer 1 and the upper conical saucer 2. In the neutral position of the ball 3, it is possible to prevent rainwater, dust, sand, and the like from entering the storage portion S, so that the rust prevention effect can be obtained even in the case of outdoor installation, and furthermore, the ball 3 can be smoothly moved. The advantage that good rolling can be favorably maintained can be obtained.
[0031]
FIG. 5 shows another embodiment of the present invention. In this embodiment, a ball housing 4A is constituted by a cylindrical body 12 having a through hole 13 at the bottom, and a lower surface of the cylindrical body 12 A friction material 14 is provided.
[0032]
That is, frictional resistance is generated between the cylindrical body 12 and the lower conical pan 1.
[0033]
Therefore, this embodiment is effective for seismic isolation of precision equipment with a light load, and the ball housing 4A operates while sliding on the lower conical tray 1 with the rotation of the ball 3, so that the ball 3 rotates. Decrease power.
[0034]
In addition, the ball housing 4A in this embodiment can be connected and used as described above, or can be used independently.
[0035]
As a result, the operation of the ball 3 is stabilized, and after the seismic isolation, the ball 3 is correctly returned to the original position.
[0036]
【The invention's effect】
As described above, according to the invention of claim 1, since the balls of each seismic isolation device roll in conjunction with each other when an earthquake occurs, the abnormal operation of the seismic isolation device is eliminated, and after the earthquake stops, each ball is moved to the lower cone. The effect of being able to automatically return to the original position between the surface pan and the upper conical pan is obtained. That is, the balls roll in the ball housing, and since the adjacent ball housings are connected to each other by the pressing band and the connecting member, the balls in each ball housing do not roll independently, and Both roll in the same direction and by the same amount.
Therefore, the position of the ball on one lower conical pan does not differ from the position of the ball on the other lower conical pan. Furthermore, the balls of each seismic isolation device do not move individually, and the degree of displacement between the ball of each seismic isolation device and the lower conical saucer becomes equal, so that it is possible to avoid abnormal seismic isolation operation. After the earthquake stops, each ball automatically returns to its original position.
[0037]
According to the second aspect of the present invention, since the ball housing is provided with the friction member that comes into frictional contact with the ball or a part of the lower conical pan, frictional resistance is given to the rolling of each ball. Thus, the effect that the operation of each ball can be stabilized in the vibration direction can be obtained.
[0038]
According to the third aspect of the present invention, since a cover for sealing the storage portion of the ball is provided between the lower conical pan and the upper conical pan and the ball housing, it is used outdoors. In this case, it is possible to prevent rainwater and dust from entering the ball storage section, thereby preventing rusting of the storage section and the ball, and maintaining the smooth rotation of the ball. Can be
[Brief description of the drawings]
FIG. 1 is an enlarged sectional view showing a main part of a seismic isolation device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing the entire seismic isolation device according to one embodiment of the present invention.
FIG. 3 is a plan view of the seismic isolation device shown in FIG.
FIG. 4 is a sectional view showing an operation state of the seismic isolation device shown in FIG.
FIG. 5 is a sectional view showing a seismic isolation device according to another embodiment of the present invention.
FIG. 6 is a conceptual diagram showing a conventional seismic isolation device.
FIG. 7 is a conceptual diagram showing a positional relationship between a ball and a lower conical pan and an upper conical pan in FIG. 5;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lower conical pan 2 Upper conical pan 3 Ball 4 Ball housing 5, 6 Cover 7 Friction member (friction material)
9 Connecting rod S, storage member

Claims (3)

Corruption seismic isolation object is located at a plurality of locations in the event of an earthquake between the foundation or substructure and seismic isolation object in seismic isolation device to avoid breaking, and foundation or substructure and seismic isolation object An upper conical saucer and a lower conical saucer respectively disposed at four corners of a square between; a ball rotatably sandwiched between the upper conical saucer and the lower conical saucer; A cylindrical ball housing that surrounds the periphery in the horizontal direction and holds the ball so that it can roll freely; a press band attached to the outer periphery of the ball housing; and a connection that is connected to the press band and extends in the primary direction and the secondary direction A seismic isolation device comprising a member and connecting the presser bands adjacent in the primary direction and the secondary direction with the connecting member . The seismic isolation device according to claim 1, wherein the ball housing is provided with a friction member that frictionally contacts the ball or a part of the lower conical pan. 2. The seismic isolation device according to claim 1, wherein a cover that seals the storage portion of the ball is provided between the lower conical pan and the upper conical pan and the ball housing. 3.

Images