JPH04176956A - Floor earthquake-proof device - Google Patents

Abstract

PURPOSE:To miniaturize a floor earthquake-proof device by fixing a plural number of springs, provided for restraining floor slabs from making horizontal movement, in a state of butting each other and fixing the other ends to a body through the medium of ropes which are provided with stopper members in order that the springs actuate only toward the tension side. CONSTITUTION:A floor slab 7 is supported with plural slippage supporting portions 8 so as to allow the floor slab 7 to make horizontal movement. One-side ends of plural pre-tension springs 5 are arranged on a ring jig 11, provide in a floating condition, in a state of butting each other and the other ends are coupled to rope members 4. Each rope 4 is then run through a framework 9, hung from the slab 7, and each end thereof is secured to a prop 6 fixed to the body. A stopper member 10 is fixed to each rope 4 and placed in the outer side of the framework 9 to give only the tension power to the springs 5 when the slab 7 makes horizontal movement. Thus all of the springs can contribute to the restoring action of the slab to its steady state position and the device can be miniaturized by shortening the spring length to about half of that in conventional use.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a floor seismic isolation device for reducing horizontal vibrations applied to precision equipment etc. due to seismic vibrations, traffic vibrations, etc. in computer rooms, semiconductor factories, etc.

<Conventional technology> Various seismic isolation devices have been proposed in the past.

The same type of seismic isolation device as in JP-A No. 62-86266 is shown in Figures 4a and 4b.
7 is supported horizontally movably, and this sliding support part 4
8 bears the vertical load applied to the floor structure 47. A container-shaped damper main body 41 is filled with a viscous liquid 42 , and a movable element 43 attached to a floor structure 47 is immersed in the viscous liquid 42 . Eight pre-tension springs 45 are connected radially, and one end of each spring 45 is fixed to a frame 46 such as a slab.

Further, the lobe member 44 is fixed to the movable element 43 by passing through a ring-shaped jig 49, and the lobe member 44 is fixed to the movable element 43 through a ring-shaped jig 49.
4 has a locking member 50 fixed to the inside of the jig 49. The locking member 50 and the jig 49 are configured to lock only in the direction in which the pre-tension spring 45 is pulled.

<Problems to be Solved by the Invention> However, in this type of seismic isolation device, the front arm tension spring 45 is connected to the mover 43 via the rope member 44 that does not transmit compressive force but transmits tensile force. Therefore, if the value of the restoring force of the spring-piece and the value of the spring constant of the spring-piece are respectively F, then the direction in which the seismic force is applied varies from the minimum O'' direction to the maximum. Naru22.5@
Between directions, F varies from 2.41F to 2.61F and K also varies from 2.41 to 2.61 (fourth
There was a directional dependence (see figure a).

For example, when the floor structure 47 moves relative to the building frame in the direction indicated by arrow B, the mover 43 also moves in this direction (FIGS. 5a and 5b).

Pre-tension springs 45□ to 453 located in the direction of movement
are locking members 501-50. The rope member 44 between the mover 43 and the locking member 50 locks with the jig 49.
' is only bent and does not work at all, and the movable element 43 has a pre-tension spring 45 located on the opposite side. ~45. The contraction force associated with the elongation acts on the force that pulls it back to its normal position.

In this way, in the conventional seismic isolation device, the moving floor structure 4
When pulling 7 back to the normal position, only about half of the child tension springs are in operation at any given time, and in order to compensate for this, it is necessary to further increase the number of coil springs installed or increase the size of the structure itself. There was a drawback.

The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a floor seismic isolation device that has a simple and compact structure and has an excellent seismic isolation function.

Means for Solving the Problems> The present invention has been made in view of the above objects, and the gist thereof is to provide a support portion that bears a vertical load, and a floor structure that is horizontally movably supported by the support portion. In a floor seismic isolation device having a body and a plurality of elastic members that restrain horizontal movement of the floor structure, one end of each of the elastic members is fixed to each other in abutted state, and the other end is fixed to each other under a compressive force. Each of the connecting members is provided with a locking member that locks with the floor structure, so that the floor structure is fixed only in the direction in which the elastic member is pulled. A floor seismic isolation device is characterized in that a structure and a locking member are locked.

Note that the connection member that transmits only tensile force and not compressive force includes cable members such as lobes and wires.

This refers to chain members, etc.

<Example> A floor seismic isolation device according to the present invention will be described based on the accompanying drawings.

As shown in Figures 1a and lb, the floor seismic isolation device has an octagonal floor slab 7 that is horizontally movably supported by a plurality of sliding bearings 8. The pre-tension springs 5, which are zero-elastic members that bear the vertical load applied to the springs, are fixed to the floating ring jig 11 with their one ends butted against each other, and are arranged radially.

On the other hand, the other end of the pre-tension spring 5 is connected to a rope member 4 that does not transmit compressive force to the spring 5 but only transmits tensile force.

Further, each rope member 4 passes through a frame 9 lowered from the floor slab 7, and its end portion is fixed to a support 6 fixed to the frame, and a locking member 10 is fixed in the middle thereof. This locking member 10 is located outside the frame 9, and therefore locks with the frame 9 so as to apply only a tensile force to each pretension spring 5 when the floor slab 7 moves horizontally. It is something.

Here, 1 to explain the base isolation mechanism, for example, 2nd a,
When the floor slab 7 moves horizontally in the direction shown by arrow A in Figure 2b, the frame 9 of the floor slab 7 and the locking member 10. ．． 10□
, 10. are locked, and the pre-tension springs 5□, 5□, 5. expands. Pre-tension springs 5□, 5□, 53 due to this extension
The locking member 10 is subjected to the contraction force of . ．． 10. ．． 10. teeth,
It acts to pull the floor slab 7 back to its central, steady position.

At the same time, other pretension springs 54-5. The ring jig 11 stretches the ring jig 11, but due to the contraction force caused by this elongation, the pre-tension springs 54 to 58 act to exert a reaction force on the support column 6 and pull the ring jig 11 back to its normal position. do.

Each of the pre-tension springs 51 to 5. The floor slab 7, which has been pulled back to its normal position by the action of the locking member 10., moves in the direction opposite to the arrow A due to inertia. ~1
07, and each pretension spring 5□ to 5.
The plow pulls it back toward its normal position. After repeating this relative reciprocating motion (damped vibration), the floor slab 7 comes to rest at a normal position. In addition, during this reciprocating movement,
Since the rope members 4' between each of the locking members 5 and the columns 6 located in the direction in which the floor slab 7 moves are bent, the structure is such that no compressive force is transmitted to the columns 6 fixed to the frame.

Above, we have explained the case of vibration in the direction of arrow A.
Even if the floor slab 7 vibrates not only in this direction but in any direction, the floor slab 7 is similarly pulled back to the normal position by the functions of the above-mentioned members.

When eight pre-tensioned springs are used, the changes in the spring restoring force and spring constant with respect to the vibration direction are shown from the lowest 0° force direction to the highest 22.5@ direction (Part 1a
In this case, all the pretension springs contribute to pulling the floor slab 7 back to its normal position, so if the restoring force of the spring and the spring constant are respectively F, then the combined restoring force is F. The force varies from 2.41F to 2.61F, and the combined spring constant varies from 1.21 to 1.30.

This is compared to the conventional 4a using the same 8 pretension springs.
When compared with the case shown in the figure, it can be seen that the restoring force of the 1-component is unchanged, but the spring constant of the 1-component is approximately half the value. Therefore, when using the same number of sub-tension springs as the conventional one, the floor seismic isolation device shown in this embodiment has a pre-tension spring with half the spring length compared to the conventional seismic isolation device shown in Fig. 4a. Also, substantially the same composite spring constant can be obtained.

In addition, in this embodiment, the lobe member 4 penetrates the frame 9,
Although the mechanism for locking with the frame 9 using the locking member 10 fixed to the rope member 4 has been illustrated, as shown in FIG.
Connecting to the end of the pre-tension spring 5 is a rigid member 12 having a U-shaped cross section and locking with the frame 9 at its side wall portion 12a;
It is also possible to have a structure in which one end of the rigid member 12 is fixed to the support column 6 via the lobe member 4. In this case as well, the frame 9 and the rigid member 12 are engaged only in the direction that applies a tensile force to the pre-tension spring 5. As such, the structure is such that the frame 9 is disposed inside the side wall portion 12a.

Further, in this embodiment, one end of each pre-tension spring 5 is fixed to the ring jig 11, but the end of each pre-tension spring 5 may be directly connected. Although a pre-tension spring is shown as an example of the member, it is not particularly limited to other materials as long as it is an elastic material with good deformability and resistance to tension, such as a rubber material.

Furthermore, the shape of the floor slab was made octagonal, and the number of pretension springs used was eight, but this is just an example;
The design can be changed as desired, such as the shape of the floor slab and the number of springs used.

Further, in this embodiment, a mechanism is shown in which the floor slab is horizontally movably supported by the sliding bearing part, but other supporting members such as bearings and rollers that can support the floor structure with low friction may also be used. It is not particularly limited.

<Effects> According to the floor seismic isolation device of the present invention, each elastic member is fixed to each other with one end abutted against each other.

The other end is connected to a locking member, and the floor structure and the locking member are locked only in the direction in which the elastic member is pulled. Therefore, even when the floor structure vibrates horizontally due to earthquake motion, etc., all the elastic members contribute to pulling the floor structure back to its normal position. The overall spring constant of each elastic member can be reduced to approximately 1/2 compared to the device.

Therefore, when a spring member is used as the elastic member for the floor seismic isolation device of the present invention, if the spring length is approximately half that of the conventional one, it will exhibit the same seismic isolation function as the conventional seismic isolation device. This greatly contributes to the miniaturization of seismic isolation devices.

[Brief explanation of drawings]

FIG. 1a is a perspective plan view showing a floor seismic isolation device according to the present invention,
Figure 1b is a sectional view taken along the line Ib-Ib in Figure 1a, Figure 2a is a perspective plan view showing the floor slab moved in the direction of arrow A, and Figure 2b is a sectional view taken along the line nb-nb in Figure 2a. A sectional view, 3rd WI is a partial sectional view showing another embodiment, FIG. 4a is a perspective plan view showing a conventional seismic isolation device, FIG. 4b is a sectional view taken along line IVb-IVb in FIG. 4a, and FIG. 5a is a perspective plan view showing the floor slab moved in the direction of arrow B in FIG. 4a, and FIG. 5b is a perspective plan view showing the state in which the floor slab in FIG.
FIG. 3 is a cross-sectional view taken along line b-vb. 4. Lobe member (connecting member), 5. Pretension spring (elastic member), 7. Floor slab (floor structure). 8... Sliding bearing part (bearing part), 10... Locking member.

Claims (1)

[Scope of Claims] A floor isolation system having a bearing part that bears a vertical load, a floor structure supported so as to be horizontally movable by the bearing part, and a plurality of elastic members that restrain the horizontal movement of the floor structure. In the vibration device, one end of each of the elastic members is fixed to each other in a butted state, and the other end is fixed to the frame via a connecting member that transmits only tensile force without transmitting compressive force, and each of the connecting members The floor seismic isolation device is characterized in that a locking member that locks with the floor structure is provided, and the floor structure and the locking member are locked only in a direction in which the elastic member is pulled.