JPH1047430A - Base-isolation mount device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold an article stationary at its predetermined home position on a base-isolation mount device which is adapted to be disposed under an article for protecting the article from vibrations, improve its reliability, reduce its size and thickness, simplify its structure, manufacture it at a lower cost and facilitate its operation. SOLUTION: A base-isolation mount device comprises a horizontal fixed mount 10 coated at least its upper face with non-magnetic material, a movable mount 12 which is situated above the fixed mount 10 and is horizontally movable relative to the fixed mount 10 with a fixed clearance held therebetween, a first magnetic member 34 fixed on the movable mount 12 to face close the upper face of the fixed mount 10, and a second magnetic member 36 embedded in the fixed mount 10. At least either one of the first and the second magnetic members is a magnet, and these members cooperate with each other to generate holding power to hold the movable mount 12 at its predetermined home position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation table device used under an object to protect the object from vibration such as an earthquake.

[0002]

2. Description of the Related Art Furniture, cabinets, and the like have been conventionally fixed to floors, ceilings, and walls in order to prevent furniture, cabinets, and the like placed on the floor from falling down during an earthquake or the like.

[0003] Also, valuable works of art, especially sculptures, ceramics,
Archeological reference materials are severely damaged when they fall or fall due to vibrations such as earthquakes. For this reason, it is being considered to install a seismic isolation device that absorbs vibration below these. For example, a special buffer that absorbs and attenuates horizontal vibrations may be laid under objects. In this case, rubber or metal having a special structure having a damping function can be considered as the buffer.

Further, a weight is provided on the mounted object side so that the moving direction and the moving speed can be controlled, and the direction and magnitude of the vibration are detected by a piezoelectric element or an acceleration sensor, etc. A device that absorbs vibration by moving the weight in a predetermined direction is conceivable.

[0005]

2. Description of the Related Art The method of fixing an object to a floor, a ceiling, a wall, or the like not only causes the fixing tool to become large and obstructive, but also does not allow the fixing tool to be directly attached to some objects. For example, it is difficult to directly attach a fixture for works of art.

[0006] It is difficult to optimally set the return force of the buffer in a method of laying a special buffer under the object. For example, if the restoring force of the buffer is set to be weak so that weak vibrations can be sufficiently absorbed, there is a problem that the object swings near a predetermined return position and does not stand still. Therefore, it is conceivable to hold the movable table at a predetermined position with a pin or the like to stop the movable table, but there is a problem that the reliability of operation is low with respect to an external force applied suddenly. Conversely, if the restoring force of the buffer is set too high, weak vibrations cannot be sufficiently absorbed.

The method of moving the weight in the direction of absorbing vibration requires a sensor, a brake, a power source for the sensor, and maintenance and inspection thereof are troublesome, and the structure is complicated, large-scale, and expensive. is there. For this reason, practicality was poor. In addition, these conventional arts have a problem that they are obstructive and hinder the viewing, especially when they are used for works of art.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is needless to say that an object can be held at a return position when a return force for returning the object to the return position is not applied.
When applying a restoring force to the object, the object can be stopped at a predetermined return position while appropriately setting the restoring force, so that it is highly reliable against sudden external forces, and it is possible to reduce the size, especially the thickness. It is an object of the present invention to provide a seismic isolation table device which can be manufactured simply and inexpensively, and which can be easily used simply by laying it under an object.

[0009]

According to the present invention, an object of the present invention is to provide a seismic isolation table apparatus which is used to protect an object from vibration by being placed under the object. A fixed table, a movable table positioned above the fixed table and capable of moving relatively in the horizontal direction while maintaining a fixed interval with respect to the fixed table, and the movable table so as to be opposed to and close to the upper surface of the fixed table. A movable magnetic table including a fixed first magnetic member and a second magnetic member embedded in the fixed table, wherein at least one of the first and second magnetic members is a magnet and cooperates with each other; The seismic isolation table device is characterized in that it generates a holding force for holding the target at a predetermined return position.

If a return means for returning the movable base to a predetermined return position is added, the movable base can be automatically returned. It is desirable that at least one of the first and second magnetic members is a permanent magnet, and it is particularly preferable that the second magnetic member be freely movable up and down. That is, when the first magnetic member is located above, the second magnetic member rises and approaches the first magnetic member, and the attraction force of both magnetic members is sufficiently increased. When the attraction force is weakened, the second magnetic member falls and allows the movable table to move smoothly.

The second magnetic member is held in a cylindrical holder so as to be freely movable up and down and eccentric from a vertical center line, and the position of the second magnetic member can be adjusted by rotating the holder. It is desirable. The return means can be constituted by a plurality of annular wires. In this case, the restoring force of each wire acting on the movable platform cooperates to return the movable platform to the return position.

[0012]

FIG. 1 is a perspective view of one embodiment of the present invention, and FIG.
Is a plan view of the movable base, and FIG. 3 is a sectional view taken along the line III-III. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is a cross-sectional view taken along the line VV, and FIG. 6 is a diagram illustrating the operation of the first and second magnets.

In FIG. 1, reference numeral 10 denotes a lower fixed base;
Is an upper movable table, and the movable table 12 is smaller than the fixed table 10. The fixed base 10 is mounted on a floor, a shelf, a desk, or the like.
The movable base 12 has legs 14 at four corners. Each leg 14 is bent at a right angle so as to surround the corner of the movable base 12 from outside along two adjacent sides.

The movable base 12 is made of wood, and a metal weight plate 16 is fixed to the lower surface thereof. That is, as shown in FIGS. 4 and 5, the weight plate 16 is fixed to the movable plate 12 with four bolts 20 with the spacer 18 interposed between the weight plate 16 and the bottom surface of the movable plate 12. Reference numeral 22 denotes an embedded nut into which the bolt 20 is screwed, which is fixed to the movable plate 12 side.

Reference numeral 24 denotes a universal bearing as a supporting means. As shown in FIG.
It has one metal ball 26 and a retainer 28 for holding the ball 26 so that a part thereof projects. The retainers 28 of the four sets of universal bearings 24 are fixed near the four corners of the weight plate 16 and hidden inside the feet 14 as shown in FIG.

Here, the height of the four universal bearings 24 and the dimensions of the ball 26 are the same, and the ball 26 projects slightly below the foot 14. Therefore, the movable base 12 is superimposed on the upper surface of the fixed base 10 by contacting the ball 26, and at this time, the feet 14 are slightly lifted from the upper surface of the fixed base 10. Therefore, the movable table 12 can move horizontally on the fixed table 10.

In FIG. 5, reference numeral 30 denotes a magnet holder, and four magnet holders are fixed to the lower surface of the weight plate 16 adjacent to the free bearing 24. The magnet holder 30 is made of a non-magnetic material such as aluminum or plastics in a substantially cylindrical shape. The upper end is fixed to the weight plate 16 by three screws 32 (only one is shown). The lower end of the magnet holder 30 is loaded with a permanent magnet 34 as a first magnetic member, and the lower surface thereof faces the upper surface of the fixed base 10 with a slight gap.

A permanent magnet 36 as a second magnetic member facing the four magnets 34 is mounted on the fixed base 10 so as to be freely movable up and down. That is, in a state where the movable base 12 is placed at a predetermined return position, a magnet holder 38 is embedded at a position facing the first magnet 34 from below,
A permanent magnet 36 is loaded in a cavity 40 provided in each magnet holder 38.

Here, the magnet holder 38 is made of a nonmagnetic material such as aluminum or plastics in a cylindrical shape, and has a cavity 40 formed eccentrically from the center axis thereof. The magnet holder 38 is loaded from below into a loading hole 42 previously formed in the fixed base 10. The magnet holder 38 has a driver groove 44 on the lower surface, and can be rotated by a driver (not shown) from below. Therefore, the position of the magnet 36 can be adjusted by rotating as shown in FIG.

The fixing base 10 is made of a non-magnetic material such as wood, stone or resin, and a thin top plate 46 made of a non-magnetic material such as hard resin is stuck on the upper surface thereof. The front plate 46 ensures the separation between the first magnet 34 and the second magnet 36, and
Magnetic dirt attached to the surface of the front plate 46 is easily wiped off to prevent the dirt from hindering the operation of the bearing 24. A felt 48 is attached to the lower surface of the fixed base 10 so that the fixed base can be stably fixed to a desk, a shelf, a floor, or the like.

Next, a return means 50 for returning the movable base 12 to a predetermined return position will be described with reference to FIGS. 7 is a plan view showing the arrangement of the wires and the like, FIG. 8 is a sectional view taken along the line VIII-VIII, and FIG. 9 is an exploded perspective view.

Reference numeral 52 denotes a substantially disk-shaped intermediate member, and a universal bearing 54 is mounted at the center of the lower surface thereof. The ball 56 of the universal bearing 54 protrudes downward from the lower surface of the intermediate member 52, and comes into rolling contact with the upper surface of the fixed base 10. A resin 58 having excellent slidability, such as Teflon (trade name), is attached to the upper surface of the intermediate member 52. In addition, a protrusion for restricting the intermediate member 52 from being largely inclined by contacting the lower surface of the weight plate 16 is formed upward on the peripheral edge of the resin 58.

The intermediate member 52 and the fixed base 10 are connected by three annular lower wires 60. That is, the three lower wires 60 are respectively fixed to the intermediate member 52 so as to be inscribed in the outer periphery of the intermediate member 52 at equal angular intervals, and the position farthest from the intermediate member 52 is fixed to the upper surface of the fixing base 10.

The intermediate member 52 and the movable base 12 are
The three annular upper wires 62 are connected. That is, the three upper wires 62 are fixed to the intermediate member 52 so as to be inscribed in the outer periphery of the intermediate member 52 at equal angular intervals, and the position farthest from the intermediate member 52 is fixed to the movable base 10.

The upper and lower wires 62 and 60 used here may be formed by combining three independent annular wires, respectively. Each wire is formed by bending a single wire into a three-leaf shape, and the central portion thereof is formed. You may fix to the outer peripheral surface of the intermediate member 52.

The wires 62, 6 used in this embodiment
0 is made of a braid. Here, the braided body is a wire element formed by twisting a large number of metal wires having spring elasticity such as a thin piano wire, and a plurality of the wire bodies are further assembled and braided into a wire shape or a braided shape or a band shape. The wires 62 and 60 have a return force returning to a circular shape, and also have a large damping action due to friction between the thin metal wires constituting the wires.

In this apparatus, a fixed base 10 is placed on a floor or a shelf, and an object is placed on an upper movable base 12 for use. If the floor or shelf vibrates due to an earthquake or the like in this state,
Zero also shakes together. The impact at this time is caused by the attractive force between the first and second magnets 34 and 36 and the return means 50
If the movable table 12 is larger than the sum of the holding force for holding the movable table 12 at the return position, the movable table 12 escapes from the return position and starts moving. The movable base 12 and the objects thereon are supported by the universal bearing 24 and move horizontally.

When the magnet 34 separates from the magnet 36 and the attractive force between them becomes smaller than its own weight, the magnet 36
Falls in the magnet holder 38. Magnet 3 of movable table 12
4 moves over the magnet holder 38 during the movement, the second
The magnet does not rise immediately, but remains dropped. Therefore, thereafter, the movable table 12 is mainly placed on the return means 5.
Only the return force by the zero wires 62 and 60 acts and vibrates. The relative displacement at this time is absorbed by the deformation of the wires 60 and 62, and this energy is absorbed by the wires 60 and 62. For this reason, the vibration applied to the object is quickly reduced, and damage to the object can be prevented.

Since the upper wire 62 and the lower wire 60 are each radially combined, all the wires 60 and 62 are simultaneously deformed when the movable table 12 is moved in all directions on the horizontal plane. Generate a restoring force (combined force) in the direction of returning the movable table 12 to the original position (return position) in cooperation with each other. Therefore, the movable base 12 can be returned to the original return position and stabilized. At this time, the braided wires 62 and 60 themselves can absorb and attenuate the vibration energy. For this reason, the vibration of the movable base 12 is attenuated promptly and stops.

When the movable table 10 is returned to the original restoring position and stopped, the upper first magnet 34 is positioned above the lower magnet holder 38, and the lower second magnet 36 is attracted upward. . The two magnets 34 and 36 approach each other and generate a sufficient holding force to stop the movable table 10 at the return position. Therefore, the movable base 10 and the objects thereon do not move unstably.

In order to match the positions of the first magnet 34 and the second magnet 36, the felt 48 (FIG. 6) on the back surface of the fixing base 10 is peeled off, and the magnet holder 38 is removed by a driver (not shown). Just turn it. Since the cavity 40 of the magnet holder 38 is eccentric with respect to the central axis of the holder 38, the position of the magnet 36 can be changed by the rotation of the holder 38.

In the above embodiment, the intermediate member 52 is interposed between the fixed base 10 and the movable base 12, and the intermediate member 5
2 and the fixed base 10 are connected to the intermediate member 5 by the lower wire 60.
2 and the movable table 12 were connected by the upper wire 62. Therefore, the movable range of the movable base 10 is increased, and
The settable range of the return force during the vibration of 0 can be expanded. However, the present invention can eliminate the return means. When the return means is used, a means other than the return means having the structure of this embodiment may be used.

For example, the movable table 12 and the fixed table 10 may be directly connected by one set of wires without the intermediate member 52. Instead of the plurality of annular wires being independent, one annular wire may be used by bending it into a three-leaf or four-leaf shape. An elastic material such as a coil spring, a leaf spring, or rubber can be used instead of the wire.

It is desirable to use three or more sets of universal bearings using balls as the support means in order to enable smooth movement. However, a resin plate or a resin sheet having a small sliding resistance may be used instead.

If the first and second magnetic members are both permanent magnets as in the above embodiment, the holding force can be increased, but only one of them may be a permanent magnet. In the above embodiment, four sets of the first and second magnets are provided, but only one set may be provided near the center of the movable plate.

[0036]

As described above, according to the first aspect of the present invention, the fixed base and the movable base relatively movable with respect to the fixed base are opposed to each other in a state where the movable base is at a predetermined return position. First and second magnetic members are provided, and at least one of the two magnetic members is a magnet, so that the movable table is held at the return position by an attractive force generated between the two members.

Thus, the movable table can be held stationary at the return position, and can be easily escaped from the predetermined position when an exciting force is applied to the movable table due to an earthquake or the like. Therefore, high reliability, miniaturization and thinning can be achieved,
It is also cheap. When a return means for returning to the predetermined return position is added, the movable table can be automatically returned by an appropriate return force of the return means (claim 2).

The first and second magnetic members used here are preferably permanent magnets. It is preferable that the lower magnetic member be movable up and down within a predetermined range (claim 4).
In this case, when a predetermined or more exciting force is applied, the movable table escapes from the return position, and thereafter, the second magnetic member falls and the attraction force by the magnet hardly acts. For this reason, the movable base can move smoothly and generate a sufficient vibration isolation function. When the movable base is returned to the return position and stopped, the second magnetic member is attracted by the first magnetic member and rises to generate a predetermined stationary holding force.

In this case, if the second magnetic member is held in a cylindrical holder so as to be freely movable up and down and eccentric from its vertical center line, the second magnetic member is rotated by rotating the holder. Can be adjusted (claim 5). Therefore, when using a plurality of sets of the first and second magnetic members,
Positioning of each set of magnets can be easily performed.

When the return means is used, it can be constituted by combining a plurality of annular wires made of unbalanced bodies. Here, at least one of the wires is fixed to the fixed table and the other is fixed to the movable table, and a return force is generated by bending of the wire itself. It goes without saying that the resultant force of the return force of each wire is directed in the direction of returning the movable table to the return position.

When this wire is used, an intermediate member may be interposed between the fixed base and the movable base, and the intermediate member may be connected to the fixed base and the movable base by a plurality of annular wires. ). In this case, the annular wire is used in two layers, so that the movable range of the movable table can be expanded, and the degree of freedom in design increases. Further, since the number of wires used increases, it is possible to increase the damping capacity.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of the present invention.

FIG. 2 is a plan view of a movable plate.

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

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a sectional view taken along line VV in FIG. 3;

FIG. 6 is a diagram for explaining the operation of the first and second magnets;

FIG. 7 is a plan view showing the arrangement of wires and the like.

8 is a sectional view taken along line VIII-VIII in FIG.

FIG. 9 is an exploded perspective view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fixed stand 12 Movable stand 14 Leg 24 Free bearing as support means 30 Magnet holder 34 Permanent magnet as first magnetic member 36 Permanent magnet as second magnetic member 38 Magnet holder 52 Intermediate member 60, 62 Wire

Claims (7)

[Claims] 1. A seismic isolation table device which is placed under an object to protect the object from vibration, comprising: a horizontal fixed table having at least an upper surface covered with a non-magnetic material; A movable table which is positioned above and is relatively movable in the horizontal direction while maintaining a fixed interval with respect to the fixed table, and a first magnetic member fixed to the movable table so as to be close to and opposed to the upper surface of the fixed table. A second magnetic member embedded in the fixed base, wherein at least one of the first and second magnetic members is used as a magnet to cooperate to hold the movable base at a predetermined return position. A seismic isolation stand characterized by generating force. 2. A seismic isolation table device which is placed under an object and protects the object from vibration, wherein at least an upper surface is provided above a horizontal fixed table covered with a top plate made of a non-magnetic material having a flat surface. A horizontal movable base positioned thereon, supporting means interposed between the fixed base and the movable base and allowing relative movement in the horizontal direction, and a predetermined return to the movable base interposed between the movable base and the fixed base Return means for giving a return behavior to the position direction, a first magnetic member fixed to the movable table so as to be close to and opposed to the upper surface of the fixed table, and a second magnetic member embedded in the fixed table. And at least one of the first and second magnetic members is used as a magnet so that they cooperate to generate a holding force for holding the movable table at the return position. Shaking table equipment. 3. The seismic isolation table apparatus according to claim 1, wherein at least one of the first and second magnetic members is a permanent magnet. 4. The apparatus according to claim 1, wherein the second magnetic member is mounted so as to be freely movable up and down, and is attracted by the first magnetic member and held at the ascending position when the movable table is near the return position. Seismic isolation table equipment. 5. A second magnetic member is vertically movably held by a substantially cylindrical holder made of a non-magnetic material buried vertically below a front plate of a fixed base and eccentrically held from a vertical center line, By rotating the holder about a vertical center line, a second
The seismic isolation table device according to claim 4, wherein the position of the magnetic member is adjustable. 6. The return means includes a plurality of annular wires formed of a braided body having at least one location fixed to a fixed base and at least one location fixed to a movable base, and the restoring forces of the respective wires cooperate. 3. Acting in a direction to return the movable table to the return position.
The seismic isolation table device according to any one of to 5. 7. The return means includes an intermediate member located between the fixed base and the movable base, which can be moved relative to each other horizontally and horizontally, and at least one center is provided at the fixed base and at least one base is provided at the middle. A plurality of annular lower wires made of a braid fixed to the member, and a plurality of annular upper wires made of a braid fixed at least at one portion to the intermediate member and at least one portion to the movable table, respectively. The seismic isolation table apparatus according to any one of claims 2 to 5, further comprising: a restoring force of the lower wire and the upper wire cooperating to return the movable table to a predetermined return position.