JPH0674609B2 - Seismic isolation device and seismic isolation structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a seismic isolation device and a seismic isolation structure for seismically supporting a building, a computer or other machinery.

[Prior Art] Conventionally, there has been proposed a seismic isolation device in which a support member having a concave surface portion is mounted on a support body, and a supported body is supported by a ball which can be rolled by the concave surface portion. With this seismic isolation device, a restoring force proportional to the weight of the supported object is generated, so the cycle of natural vibration is almost constant even if the weight changes, but a large supporting member is required, and the cost is expensive to manufacture and the price is high. Has the drawback of being high. In addition, an intermediate body that supports and transmits the load from the supported body to the support body is provided, and the supported body is supported by the plurality of spiral springs so that the supported body can vibrate only in a predetermined direction, and an oil damper is used. A seismic isolation device is used in which the intermediate body is supported by a plurality of spiral springs so that it can be vibrated only in a direction perpendicular to the above direction and is damped by an oil damper. Since it is necessary to use springs having different elastic coefficients depending on the weight of the support, it is inconvenient and not suitable for long-period ground motion. In addition, seismic isolation devices made of laminated rubber are often used, but they have the same drawbacks as those using the intermediate body and the spiral spring, and are not suitable for general houses whose weight tends to change due to furniture or the like. It is a thing.

[Problems to be Solved by the Invention] The present invention is easy to manufacture and has a simple structure so that the restoring force in a displaced state is proportional to the weight so that the natural frequency is substantially independent of the weight of the supported body. The present invention provides a seismic isolation device suitable for a long-period ground motion and a seismic isolation structure using the seismic isolation device.

[Means for Solving the Problems] The present invention includes a rolling element supported so as to be rollable only around a predetermined axis with respect to either one of a supported body and a supporting body,
It includes the supported body and a guide member that is attached to the other side of the support body and that contacts the rolling body and extends in the rolling direction. A seismic isolation device characterized by maintaining the lowest reference position and rolling the rolling element when the supported body moves with respect to the supporting body to gradually raise the supported body. The present invention provides a seismic isolation structure using a different seismic isolation device.

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

In one embodiment of the present invention shown in FIG. 1 and FIG.
Indicates a seismic isolation device, which is mounted between the supported body 12 and the supporting body 13 and is constructed as described below. That is, reference numeral 15 is a shaft in which two supporting portions 16 provided on the supported body 12 are horizontally penetrated and nuts 18 are fastened and fixed to screw portions 17 at both ends.
20 is a shaft around this shaft 15 through a friction member 21 which is used for a brake so as to penetrate the shaft in the center.
It is a rolling element that is rotatably mounted only around 15, and flanges 22 having a large outer diameter are formed on both sides to prevent the rolling element from falling off. An oil-free bearing may be used as the friction member 21. Reference numeral 23 denotes a rail-shaped guide member that is fixed to the support 13 with a plurality of bolts 25 and is guided between the flanges 22 so as to be sandwiched between the flanges 22, and the mounting surface 26 is horizontal.
The length is about 1.5 to 3m. This guide member has the lowest central portion, and is provided with a portion 27 having an arcuate cross section and an inclined portion 28 which is inclined so as to ascend to both sides thereof at this portion. The rolling element 20 and the guide member 23 maintain the supported body 12 at the lowest reference position with respect to the supporting body 13 at all times, and when the supported body 12 moves with respect to the supporting body 10, the rolling body 20 rolls. The supported body 12 is gradually raised. When the rolling distance of the rolling element 20 from the lowest reference position of the supported body 12 is represented by x and the restoring force received by the supported body 12 is represented by F, a characteristic diagram shown in FIG. 3 is obtained. ,
Restoring force F while the rolling element 20 passes through the portion 27 of the arcuate cross section
Is increased in proportion to the displacement x, but the restoring force F is maintained at a constant value while passing through the inclined portion 28. Supported object
The restoring force F changes in proportion to the weight of 12 and the frictional force also proportional to the weight of the supported body 12. Therefore, the cycle of the natural vibration is determined by the rolling range of the rolling element 20, and the cycle of the natural vibration is, for example, within 0.5 seconds.
28 slopes will be determined. Such seismic isolation device 10
Can be used in combination for seismic isolation in one direction orthogonal to this specific direction, and can be used in a specific direction. It can be used for seismic isolation. Further, the guide member 23 is attached to the supported body 12 so as to face downward and the support body 13 is attached.
The rolling element 20 may be rotatably connected to the. Also, rolling elements
A shaft fixed to the shaft 20 may be provided in the shaft 20, and the shaft may be rotatably supported by the supported member 12. In such a case, an oil damper, a damping device using a highly viscous fluid, or the like may be separately used to obtain the damping force. In particular, the one using a highly viscous fluid can be easily adjusted so as to have a desired damping coefficient, and it is sufficient even if there is no frictional force proportional to the weight. In addition, in order to prevent the rolling element 20 from falling off, the rolling element 20
The flanges may be provided on both sides of the guide member 23 without providing the flange 22.

FIG. 4 shows a seismic isolation device 10 according to another embodiment of the present invention, in which the guide member 23 has only an arcuate cross section, and the rolling element 20 is provided.
As shown in FIG. 5, the restoring force F is substantially proportional to the displacement x of the rolling element 20 from the reference position with respect to the guide member 23.

FIG. 6 shows a seismic isolation device 10 according to another embodiment of the present invention, in which the guide member 23 extends straight without changing the height, and the rolling element 20 has a cylindrical peripheral surface. Is supported by an eccentric shaft 15. When the displacement x of the rolling element 20 exceeds a predetermined range as shown in the characteristic diagram of FIG. 7, the restoring force F
Is reduced and is used within a range where an appropriate restoring force can be obtained.

In the seismic isolation device 10 according to another embodiment of the present invention shown in FIGS. 8 to 10, the guide member 23 is connected to both sides of the horizontal portion 30 having a constant height at the center, and the inclined portions 31 are connected by smooth curved surfaces. The rolling element 20 is supported by the eccentric shaft 15 as in the embodiment shown in FIG. On this rolling element 20, an engaging rolling portion 32 having tooth-shaped irregularities of gears is formed on one side at substantially the same outer periphery as the rolling element, and the guide member 23 is engaged with the engaging rolling portion 32. Engagement guide having teeth to be disengaged
33 is formed. Therefore, the rolling element 20 is guided by the guide member 23.
Since it does not slip at all, it can return to almost the initial state even if it rolls. FIG. 11 shows a characteristic diagram of this embodiment. As the displacement x of the rolling element 20 increases from the reference position, the restoring force F increases proportionally at first, but then decreases and increases again. It is becoming like this. Engagement rolling portion 32 and engagement guide portion as in this embodiment
33 is particularly necessary when the rolling element 20 is supported by the eccentric shaft 15, and may be provided even in the case of the embodiment shown in FIG. 6, and the rolling element 20 is attached to the guide member 23. it may be filed provided in all cases to prevent along connexion slipping. 12th
As shown in the drawing, a sprocket-shaped engagement rolling portion 32 and a chain-shaped engagement guide portion 33 may be provided.

In another embodiment of the present invention shown in FIGS. 13 and 14,
The rolling body 20 is mounted around the shaft 15 fixed to the supported body 12 via a friction member 21, and an annular inner member 35 is provided outside the friction member and an annular inner member 35 is provided outside thereof. An outer member 36 is provided to form the rolling element 20. Between the inner member and the outer member, an annular containing space 37 having the same axis as the shaft 15 and having a narrow thickness is formed, and a high-viscosity fluid 38 is contained therein. 40 is a sealing member, and 41 is a ball bearing.
Generally, when a frictional force is generated in the friction member 21, the rolling element 20 stops in a state where the restoring force received by the rolling element 20 is balanced with the frictional force. When the highly viscous fluid 38 has a large viscosity and the rolling element 20 rolls, a damping force is given by a slight relative rotational movement between the inner member 35 and the outer member 36, but the relative rotational movement is If it is small, the rolling element 20 is allowed to gradually roll when the rolling element 20 is stopped for a long time while the restoring force and the frictional force are balanced, and the rolling element 20 is returned to the reference position. It is something that allows you to. FIG. 15 shows a state in which an accommodation space 37 and a high-viscosity fluid 38 as shown in FIGS. 13 and 14 are provided in the embodiment shown in FIGS.

In another embodiment of the present invention shown in FIG. 16, rolling elements 20
Is attached to a shaft 15 via a friction member 21, which is rotatably supported by the supported body 12 via a pair of ball bearings 42 and extends at one end. Reference numeral 43 denotes a fixed surface portion that extends in a direction perpendicular to the shaft 15 fixed to the supported body 12.
It may be formed integrally with 12. Reference numeral 45 denotes a movable surface portion which is arranged outside the fixed surface portion and is fixed to the shaft 15 by a key 46 and which is fixed by tightening a nut 48 to a screw portion 47 of the shaft 15 and which extends in a direction perpendicular to the shaft 15. A ring-shaped accommodation space 50 having a narrow interval is formed between them, and the highly viscous fluid 51 is accommodated in this accommodation space. 52 is a sealing member. In this embodiment, the highly viscous fluid 51 generates a torque that resists almost in proportion to the rotation speed of the shaft 15, and when the rolling element 20 rotates, the shaft 15 slightly rotates and is damped to the supported body 12. With force applied, shaft 15 is similar to being almost at rest. When the rolling element 20 stops, it may stop in a state where a restoring force remains due to the frictional force.In such a case, the highly viscous fluid 51 gives the extremely viscous torque to the rolling element 20 and the rolling element 20 together with the shaft 15. It can be gradually rotated to a stable position. Also, in this embodiment,
The rolling element 20 mounted via the shaft 15 may be mounted on the supporting body 13, and the fixing surface portion 43 may be fixed to the supporting body 13 or may be integrally formed.

In each of the embodiments described above, the rolling element 20 is adapted to come into contact with the guide member 23 on the cylindrical peripheral surface, but for example, a partial oval cross-sectional shape adapted to rotate only within a predetermined range. The peripheral surface may have a shape other than the cylindrical shape, such as.

17 and 18 show one embodiment of the seismic isolation structure according to the present invention. In this figure, a mounting plate 55 is attached to the lower surface of the supported body 12, and four of the above-mentioned same characteristics which are displaceable in the same direction between this mounting plate and the intermediate body 56 arranged below it. A seismic isolation device 10 is provided. Intermediate 56
Is disposed between the supported body 12 and the supporting body 13 to support the load from the supported body 12 and transmit the load to the supporting body 13. Therefore, the supported body 12 can be displaced only in the direction indicated by the arrow X with respect to the intermediate body 56. Further, as shown by Y, four seismic isolation devices 10 having the same characteristics are provided between the intermediate body 56 and the support body 13 and are displaceable in the direction perpendicular to the above direction. If the supported body 12 vibrates in an oblique direction due to an earthquake, the combined displacement of both the displacement of the supported body 12 in the X direction with respect to the intermediate body 56 and the displacement of the intermediate body 56 with respect to the support body 13 in the Y direction. It will vibrate like this.

In another embodiment of the seismic isolation structure according to the present invention shown in FIG. 19 to FIG. 22, a house provided with a concrete slab 57 in the lower part is connected to the supported body 12, and the supporting body 13 is made of reinforced concrete. The foundation structure is used. Reference numeral 58 is a tread plate that is fixed to the supported body 12 and movably covers the gap portion. In this embodiment, a plurality of seismic isolation device assemblies 60 are used. This seismic isolation device assembly consists of 4 seismic isolation devices
10 guide members arranged in parallel at a predetermined interval
There are two guide member coupling bodies 61 in which 23 are integrally coupled, and one of them is attached downwardly to the supported body 12 and is attached upwardly to the support body 13 and is attached to the supported body 12. The object and the guide member 23 are mounted so as to be arranged at the same vertical center line position in the perpendicular direction. The shaft 15 of the rolling element 20 that rolls along each upper guide member 23 is fixed to the cross-shaped coupling member 62 so as to face each other, and the lower guide member 23 is orthogonal to this. The shafts 15 of the rolling elements 20 that roll along with each other are fixed to the coupling member 62 so as to face each other. By doing so, it is possible to obtain the seismic isolation device assembly 60 which has a small space in the vertical direction and can withstand the moment about the upright axis line. In order to reduce the vertical gap, the supported
The shaft 15 of the rolling element 20 on the 12 side may intersect with the shaft 15 of the rolling element 20 on the supporting body 13 side so as to be slightly below. In the guide member coupling body 61 of each seismic isolation device assembly 60 attached to the supported body 12, the guide members 23 are arranged in parallel and extend in the direction perpendicular to the one attached to the other support body 13. There is. The intermediate member 56 is constituted by the rod members 65 that connect the connecting members 62 of the seismic isolation device assemblies 60 to each other, whereby the shaft 15 of each rolling element 20 is maintained horizontal and is not inclined.

FIG. 23 is a characteristic diagram showing a comparison between a seismic isolation device according to an embodiment of the present invention and a conventional seismic isolation device in the case of assumed earthquake motion. In this figure, the following symbols are used.

f: Frequency a: Acceleration amplitude G: Earthquake 0.1-0.9Hz has maximum velocity amplitude 70cm / sec 0.9-10Hz has maximum acceleration amplitude 400Gal A: Vibration response of this invention The guide member is an arc shape with a radius of 720cm near the center. Both sides are linearly inclined at 0.05 rad, and the total length is about 3 m.

Rolling element radius 12 cm Effective friction coefficient converted to the part where the rolling element contacts the guide member
0.03 Viscous damping coefficient based on air resistance 0.19Kgf sec / cm Support weight 1000Kgf B: Linear characteristic Vibration response of conventional seismic isolation device using viscous damping device such as spring and oil damper Natural frequency 0.5Hz Damping ratio 0.3 Damping coefficient 1.92Kgf sec / cm Support weight 1000Kgf According to this characteristic diagram, conventional seismic isolation devices have a large acceleration part for seismic motion of 1Hz or less and a little long period. It can be understood that the seismic isolation effect is sufficiently obtained even in the case of no acceleration.

[Effect of the invention] According to the invention described in claim 1, since the seismic isolation device 10 is composed of the rolling element 20 and the guide member 23 extending in the rolling direction of the rolling element, it can be easily manufactured with an extremely simple structure. A seismic isolation device that can be operated in one direction to obtain a long period natural frequency regardless of the weight of the supported body 12 and has a good seismic isolation effect even for long period earthquakes of 1 Hz or less. Is obtained.

According to the second aspect of the present invention, since the rolling element 20 is provided with the flange 22 for preventing the falling element in the first aspect, even if a complicated force due to an earthquake acts, the rolling element 20 is guided by the guide member 23. It doesn't fall off.

The invention according to claim 3 is an engaging rolling portion integrally with the rolling element 20.
32 is provided, and the guide member 23 is provided with the engagement guide portion 33 adapted to be engaged with and disengaged from the engagement rolling portion, so that the rolling element 20 can be completely prevented from slipping. . Such characteristics are particularly necessary in the case where the rolling element 20 is supported by an eccentric shaft.

The invention according to claim 4 has an advantage that the damping force can be obtained by the frictional force which can be most easily constructed.

The invention according to claim 5 has an advantage that a highly viscous fluid that can easily obtain a desired damping force can be used over that by such frictional force.

In the invention according to claim 6, when the rolling element 20 stops, the rolling element 20 may stop in a state where a restoring force slightly remains due to the frictional force.
In such a case, there is an advantage that the rolling element 20 can gradually rotate together with the shaft 15 to a stable position while giving a very slight resistance torque by the highly viscous fluid 51.

In the invention according to claim 7, the intermediate body 56 is provided between the supported body 12 and the support body 13, and the seismic isolation device 10 that can be operated in a direction substantially perpendicular to the upper and lower sides of the intermediate body is used. It is possible to obtain a seismic isolated structure that can be seismically isolated from all horizontal seismic motions.

Since the invention according to claim 8 uses a plurality of seismic isolation device assemblies 60 in which four seismic isolation devices 10 are assembled,
It is possible to obtain a seismic isolation structure in which the portion required for seismic isolation is extremely compact and has a low height.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a seismic isolation device according to an embodiment of the present invention, FIG. 2 is a vertical sectional side view thereof, and FIG. 3 is a characteristic diagram thereof.
4 is a vertical sectional front view of a seismic isolation device according to another embodiment of the present invention, FIG. 5 is a characteristic diagram thereof, and FIG. 6 is a vertical sectional front view of a seismic isolation device according to another embodiment of the present invention. 7 is a characteristic diagram thereof, FIG. 8 is a longitudinal side view showing a seismic isolation device of another embodiment of the present invention, FIG. 9 is a sectional view taken along line 9-9 in FIG. 8, and FIG. 11 is a sectional view taken along line 10-10 in FIG.
FIG. 12 is a characteristic diagram thereof, FIG. 12 is a vertical sectional front view showing a part of the modification of the embodiment shown in FIGS. 8 to 10, and FIG. 13 is a vertical sectional front view showing a seismic isolation device of another embodiment of the present invention. Fig. 14, Fig. 14 is a vertical cross-sectional side view showing an enlarged dimension, Fig. 15 is a vertical cross-sectional side view showing a part of the modification, and Fig. 16 is a vertical cross-sectional side view showing a seismic isolation device of another embodiment of the present invention. Fig. 17, Fig. 17 is a front view showing a seismic isolation structure according to an embodiment of the present invention, Fig. 18 is a plan view thereof, and Fig. 19 is a front view showing a seismic isolation structure according to another embodiment of the present invention. , First
20 is a sectional view taken along line 20-20 in FIG. 19, FIG. 21 is a front view showing the seismic isolation device assembly, FIG. 22 is a sectional view taken along line 22-22 in FIG. 21, and FIG. It is a characteristic diagram which shows the response characteristic with respect to the ground motion of the seismic isolation apparatus by one Example of this invention, and the conventional seismic isolation apparatus. 10 …… Seismic isolation device, 12 …… Supported body, 13 …… Support body, 15…
… Shaft, 20 …… Rolling element, 21 …… Friction member, 22 …… Flange, 23 …… Guide member, 32 …… Engagement rolling part, 33 …… Engagement guide part, 35 …… Inner member, 36 …… Outside member, 37 …… Accommodation space, 38 …… High viscosity fluid, 43 …… Fixed surface portion, 45 …… Movable surface portion, 50 …… Accommodation space, 51 …… High viscosity fluid, 56 …… Intermediate body, 60 …… Seismic isolation device assembly.

Claims (8)

[Claims] 1. A rolling element that is supported so as to be rotatable only around a predetermined axis with respect to one of the supported body and the supporting body, and is mounted on the other side of the supported body and the supporting body. And a guide member that contacts the rolling element and extends in the rolling direction,
The rolling element and the guide member maintain the supported body at the lowest reference position with respect to the supporting body at all times, and when the supporting body moves with respect to the supporting body, the rolling body rolls to gradually move the supported body. A seismic isolation device characterized in that it is to be raised. 2. The seismic isolation device according to claim 1, wherein the rolling elements are provided on both sides with flanges having a large outer diameter to prevent falling. 3. The seismic isolation device according to claim 1, wherein:
The rolling element has an engaging rolling portion which is integrally formed with the rolling element so that the outer periphery thereof has unevenness at substantially the same position, and the guide member is engaged with the rolling element. A seismic isolation device having an engagement guide part that can be engaged with and disengaged from a moving part. 4. The seismic isolation device according to claim 1, 2 or 3, wherein the rolling element is rotated around a support member on which the rolling element is mounted or an axis fixed to the support member through a friction member. A seismic isolation device characterized by: 5. The seismic isolation device according to claim 4, wherein the rolling element has an inner part and an outer part capable of relative rotational movement, and an annular housing with a narrow interval formed between the inner part and the outer part. A seismic isolation device comprising a space and a high-viscosity fluid contained in the accommodation space. 6. The seismic isolation device according to claim 1, 2 or 3, wherein the rolling element is a friction member around an axis supported rotatably with respect to a supported body or a supporting body on which the rolling element is mounted. It is mounted so as to roll through, and is formed on a supported body or a supporting body provided with the shaft, or is fixed to this so as to penetrate the shaft in a direction perpendicular to the shaft. A fixed surface portion that extends, a movable surface portion that is fixed to the shaft and extends in a direction perpendicular to the shaft so as to form an annular accommodation space having a narrow gap between the fixed surface portion, and a high viscosity that is accommodated in the accommodation space. A seismic isolation device including a fluid. 7. An intermediate body disposed between supported bodies to support a load from the supported body and transmit the load to the support body, and one predetermined direction between the supported body and the intermediate body. 7. A plurality of seismic isolation devices having the same characteristics according to claim 1, 2, 3, 4, 5, or 6 which are arranged so as to perform seismic isolation, and the seismic isolation device between the intermediate body and the support body is substantially parallel to the predetermined direction. 7. A seismic isolation structure comprising a plurality of seismic isolation devices having the same characteristics according to claim 1, 2, 3, 4, 5, or 6, which are arranged so as to perform seismic isolation in the same direction at right angles. object. 8. The seismic isolation structure according to claim 7, wherein the four seismic isolation devices according to claim 1, 2, 3, 4, 5 or 6 are provided between the supported body and the supporting body, respectively. A plurality of sets of seismic isolation devices are assembled, each seismic isolation device assembly having two guide member assemblies having a pair of guide members arranged in parallel, one of which is The guide member of the other set is attached downward to the supported member so that the guide member is parallel to the other member, and the guide member assembly of the other member is parallel to the guide member of the other member. And the guide member assembly attached to the supported member and the guide member assembly attached to the supported member respectively so as to extend downward in a direction perpendicular to the one attached to the supported member. The rolling element that rolls along the guide member is supported by the common coupling member provided for each seismic isolation device assembly. A seismic isolation structure characterized in that each of the rolling members along the respective guide members of the holding body is mounted on a shaft having the same axis line, and the intermediate body is formed by coupling the coupling members to each other. object.