JP6706131B2 - Seismic isolation table and damping force applying member used therefor - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention is interposed between a seismic isolation target such as precision equipment, electronic equipment, and works of art and the floor surface of a building, and is used for the purpose of protecting the seismic isolation target from external vibration such as an earthquake. The present invention relates to a seismic isolation table and a damping force applying member used for the table.

Conventionally, as a measure against vibration during the transportation of seismic isolated objects such as precision instruments, electronic devices, and works of art, or against external vibration such as an earthquake when the seismic isolated object is installed in a building, these seismic isolated targets A seismic isolation table is used to isolate objects from vibrations on the floor.

As this type of seismic isolation table, the one disclosed in JP 2001-349373 A is known. The seismic isolation table includes a lower table installed on a floor surface, a plurality of lower slide guides mounted on the lower table, a slide part that moves along the lower slide guide, and the slide part. An upper slide guide that is movably held in a direction orthogonal to the lower slide guide, an upper table to which the upper slide guide is attached and a seismic isolation target is mounted, and between the slide portion and the lower table, And a plurality of elastic members that are provided between the slide portion and the upper table and that return the upper table to the initial position on the lower table.

In the seismic isolation table having such a configuration, when vibration acts on the floor surface, the slide portions freely move in the X and Y directions orthogonal to each other with respect to the lower slide guide and the upper slide guide. This makes it possible to isolate the upper table on which the seismic isolation target is placed from the vibration of the floor surface and set the period of such upper table vibration sufficiently long to reduce the shaking of the seismic isolation target. There is. Further, when the vibration of the floor surface subsides and the vibration of the upper table also subsides, the upper table is pulled back to the initial position by the tension of the elastic member.

Further, this seismic isolation table is provided with a stopper mechanism for limiting the moving range of the upper table with respect to the lower table. Specifically, a frame-shaped lower stopper is erected on the lower table, while an upper stopper that is inserted into the lower stopper is provided on the upper table. The lower stopper limits the moving range of the upper stopper, and the interference of the lower stopper and the upper stopper limits the operating range of the upper table with respect to the lower table.

JP 2001-349373 A

In the conventional seismic isolation table described above, there is no damping element for vibration of the upper table in addition to the frictional resistance acting between the lower slide guide and the upper slide guide and the slide portion. Therefore, when a large vibration energy is input to the lower table such as a large earthquake, it is difficult to keep the response displacement of the upper table within the working range of the upper table limited by the stopper mechanism. Due to the interference between the lower stopper and the upper stopper, it is difficult to appropriately control the behavior of the upper table with respect to the lower table, such as a sudden acceleration acting on the seismic isolation target mounted on the upper table. Met.

The present invention has been made in view of such problems, and an object of the present invention is to easily add a damping element for input vibration, and to prevent an excessive vibration from being input to the upper table. The purpose of the present invention is to provide a seismic isolation table and a damping force applying member used for the seismic isolation table capable of appropriately controlling the behavior of the.

That is, the seismic isolation table of the present invention includes a lower table installed on a fixed portion, an upper table on which a seismic isolation target is mounted, and the upper table in the X direction with respect to the lower table and in the Y direction orthogonal thereto. And a guide member for holding the upper table relatively immovable with respect to the lower table in the Z direction orthogonal to the X direction and the Y direction, and the upper table with respect to the lower table. And a damping force applying member that exerts frictional damping on movement. The damping force applying member is in pressure contact with both the lower table and the upper table, and moves relative to both the lower table and the upper table as the upper table moves with respect to the lower table. Is configured.

According to the present invention as described above, the damping force applying member that comes into pressure contact with both the lower table and the upper table is disposed only between the lower table and the upper table, and friction with respect to the movement of the upper table is reduced. It is possible to easily add a damping element that exerts damping to the seismic isolation table. Further, by adjusting the pressure contact force of the damping force applying member with respect to the lower table and the upper table, it is possible to arbitrarily control the magnitude of friction damping, and the behavior of the upper table with respect to the input of excessive vibration. Can be controlled appropriately.

It is a front sectional view showing an outline of a seismic isolation table to which the present invention is applied. It is a perspective view which shows an example of the guide device which can be utilized for the seismic isolation table shown in FIG. It is a top view which shows the structure of the lower table of the seismic isolation table shown in FIG. It is sectional drawing which shows an example of the damping force application member which can be mounted|worn with the base isolation table shown in FIG. It is a top view showing movement of a damping force giving member when an upper table moves to a lower table.

The seismic isolation table of the present invention and the damping force applying member used for the same will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a front sectional view schematically showing a seismic isolation table 1 to which the present invention is applied. The seismic isolation table 1 includes a lower table 2 placed on the floor surface, an upper table 3 on which a seismic isolation target object such as precision equipment, electronic equipment, and works of art requiring seismic isolation is mounted, and the lower portion. A guide device 4 for freely moving the upper table 3 with respect to the table 2 in the X direction and the Y direction (the depth direction in the plane of FIG. 1) orthogonal thereto, and is housed between the lower table 2 and the upper table 3. The damping force applying member 5 is provided.

FIG. 2 shows a specific configuration of the guide device 4. In this guide device, the guide device 4 is fixed to the lower track rail 40 laid on the lower table 2 and the lower surface side of the upper table 3 along a direction orthogonal to the lower track rail. An upper track rail 41 and a moving member 42 that moves along both the lower track rail 40 and the upper track rail 41 are provided. The moving member 42 includes a lower slide block 43 that is assembled to the lower guide rail 40 through a large number of rolling elements, and an upper slide block 43 that is assembled to the upper guide rail 41 through a large number of rolling elements. 44, and a coupling plate 45 that integrates the lower slide block 43 and the upper slide block 44 by back-to-back integration.

Each of the lower track rail 40 and the upper track rail 41 is provided with a plurality of rolling surfaces of rolling elements along the longitudinal direction. On the other hand, the lower slide block 43 and the upper slide block 44 have a large number of rolling elements rolling on the rolling surface while circulating endlessly, and the lower slide block 43 has the lower track rail 40. And the upper slide block 44 freely moves along the upper track rail 41. The lower slide block 43 is inseparably attached to the lower track rail 40, and the upper slide block 44 is inseparably attached to the upper track rail 41.

If the longitudinal direction of the lower track rail 40 is assumed to be the X direction, the moving member 42 in which the lower slide block 43 and the upper slide block 44 are integrated is arranged along the lower track rail 40 in the X direction. The upper track rail 41, to which the upper slide block 44 is attached, is movable in the Y direction orthogonal to the X direction with respect to the moving member. As a result, the upper table 3 to which the upper track rail 41 is fixed is freely movable in the X and Y directions with respect to the lower table 2.

Further, the moving member 42 is inseparable from the lower track rail 40 and the upper track rail 41. For example, a load in a direction of lifting the upper table 3 from the lower table 2, that is, a floating load is applied to the upper table 3. Even when it acts, the guiding device 4 can freely guide the upper table 3 in the X direction and the Y direction while applying a lifting load. The withstand loads of the lower slide block 43 and the upper slide block 44 can be appropriately selected according to the weight of the seismic isolation target mounted on the upper table 3.

FIG. 3 is an example of an embodiment of the seismic isolation table 1, and is a plan view showing a state in which the upper slide block 44 is separated from the coupling plate 45 and the upper table 3 is removed from the lower table 2. The lower table 2 is formed in a rectangular shape, and flanges 20 are provided on the four sides around the lower table 2 to increase the strength of the lower table 2. It is also possible to form a bolt mounting hole that can be used for connection with another seismic isolation table in the flange portion 20.

Two guide devices 4a and 4b are arranged on the lower table 2. The lower track rail 40 of each of the guide devices 4a and 4b is laid on the lower table 2 so as to form an angle of 45 degrees with each side of the lower table 2. Further, the lower track rail 40 of the one guide device 4a and the lower track rail 40 of the other guide device 4b are arranged in directions different by 90 degrees. Further, the upper track rail 41 fixed to the upper table 3 is arranged orthogonal to the lower track rail 40. For reference, the upper track rail 41 is drawn by a chain line in FIG. is there.

A plurality of lower elastic members 6a made of coil springs are provided between the coupling plate 45 and the lower table 2. The lower elastic member 6a has a longitudinal direction aligned with a direction orthogonal to the lower track rail 40, and is most suitable when the moving member 42 is located at a central position in the longitudinal direction of the lower track rail 40. It is stretched to reduce tension. Therefore, the lower elastic member 6 a expands and contracts as the moving member 42 moves along the lower track rail 40, and moves the moving member 42 to a central position in the longitudinal direction of the lower track rail 40. It exerts a pulling force in the direction of pulling back.

On the other hand, the upper table 3 to which the upper track rail 41 of the guide device 4 is fixed has the same shape as the lower table 2 described above, and is placed on the lower table 2 shown in FIG. Are stacked. As shown by the dashed line in the figure, the upper track rail 41 is orthogonal to the lower track rail 40, and the moving member 42 is present at the intersection of the upper track rail 41 and the lower track rail 40. is doing.

A plurality of upper elastic members 6b formed of coil springs are provided between the connecting plate 45 and the upper table 3. The longitudinal direction of the upper elastic member 6b coincides with the direction orthogonal to the upper track rail 41, and the tension is reduced most when the moving member 42 is located at the central position in the longitudinal direction of the upper track rail 41. It has been spread over to do. Therefore, the upper elastic member 6 b expands and contracts as the upper track rail 41 moves with respect to the moving member 42, and the moving member 42 is positioned at the center of the upper track rail 41 in the longitudinal direction. Then, a pulling force is applied to the upper table 3.

Therefore, the seismic isolation table 1 constitutes a vibration system by the action of the guide device 4, the lower elastic member 6a, and the upper elastic member 6b, and the floor table with respect to the lower table 2 installed on the floor surface. When vibration is applied from the surface, the upper table 3 can freely vibrate in the X direction and the Y direction at a cycle different from that of the lower table 2.

In the example shown in FIG. 3, two lower elastic members 6a are arranged on both sides of the lower track rail 40, and two upper elastic members 6b are arranged on both sides of the upper track rail 41. The number of elastic members 6a and 6b is changed as appropriate in consideration of the weight of the seismic isolation target object to be installed on the upper table 3 and the movement resistance of the moving member 42 with respect to the lower track rail 40 and the upper track rail 41. You can do it.

FIG. 4 shows a damping force applying member 5 housed between the lower table 2 and the upper table 3. The damping force imparting member 5 includes a disk-shaped lower friction plate 50 that contacts the lower table 2, a disk-shaped upper friction plate 51 that contacts the upper table 3, and the lower friction plate 50 that connects the lower table 2 to the lower table 2. Elastic member 52 that presses the upper friction plate 51 toward the upper table 3 while pressing the upper friction plate 51 toward the upper table 3.

The upper friction plate 51 includes a piston 53, while the lower friction plate 50 includes a cylinder 54 on which the piston 53 slides, whereby the upper friction plate 51 moves up and down with respect to the lower friction plate 50. It is held freely. In addition, a coil spring as the elastic member 52 is interposed between the lower friction plate 50 and the upper friction plate 51 in a compressed state, and the pressing force exerted by the elastic member 52 causes the upper portion to move. The friction plate 51 is in pressure contact with the upper table 3, and the lower friction plate 50 is in pressure contact with the lower table 2. A locking bolt 55 is screwed onto the tip of the piston 53 of the upper friction plate 51, and the locking bolt 55 penetrates the lower plate 50. Therefore, as shown in FIG. 4, when the damping force applying member 5 is pulled out from between the lower table 2 and the upper table 3, the head of the locking bolt 55 is caught by the lower friction plate 50, Separation of the upper friction plate 51 and the lower friction plate 50 is prevented. Further, as shown in FIG. 1, when the damping force applying member 5 is housed between the lower table 2 and the upper table 3, the head of the locking bolt 55 is lifted from the lower friction plate 50. It is set. The distance between the upper friction plate 51 and the lower friction plate 50 when the damping force imparting member 5 is pulled out from between the lower table 2 and the upper table 3 is determined by the engagement bolt 55 with respect to the piston 53. It can be adjusted by changing the fastening amount.

The structure of the upper friction plate 51 or the lower friction plate 50 is not limited to that shown in the drawing, and the design can be changed as appropriate. For example, in order to allow the damping force imparting member 5 to be laterally inserted into the narrow space between the lower table 2 and the upper table 3, a plurality of the upper friction plates 51 or the lower friction plates 50 are provided. It may be configured to be split and assembled between the lower table 2 and the upper table 3.

A friction material 56 is fixed to the upper friction plate 51 and the lower friction plate 50. By changing the friction material 56 or the spring coefficient of the elastic member 52, the upper friction plate 51 and the upper table 3 can be changed. The frictional force generated between the lower friction plate 50 and the lower table 2 can be adjusted arbitrarily.

The damping force imparting member 5 is not fixed to the lower table 2 and the upper table 3, and the upper friction plate 51 and the lower friction plate 50 of the damping force imparting member 5 have the elastic member 52. It is only in pressure contact with the upper table 3 and the lower table 2 by the pressing force of. Therefore, if the pressing force of the elastic member 52 is set appropriately, when the upper table 3 moves with respect to the lower table 2, the upper friction plate 51 slides with respect to the upper table 3, and The lower friction plate 50 also slides on the lower table 2. That is, the damping force applying member 5 gives a frictional resistance to the movement of the upper table 3 and the lower table 2.

The circular range indicated by the alternate long and short dash line in the lower table 2 shown in FIG. 3 indicates the movable range of the damping force imparting member 5 with respect to the lower table 2. The friction materials 56 fixed to the upper friction plate 51 and the lower friction plate 50 have the same friction coefficient, and the surfaces of the upper table 3 and the lower table 2 in contact with the friction material 56 have the same roughness. When the upper table 3 is moved by the distance a with respect to the lower table 2, the damping force imparting member 5 is separated from the lower table 2 and the upper table 3 by a distance a. It will move by a/2.

In consideration of this, a movable range of the damping force imparting member 5 is defined between the lower table 2 and the upper table 3, and the damping force imparting member 5 is in the movable range. The guide device 4 is set so as not to interfere with the moving member 42 and the elastic members 6a and 6b. The diameter of the movable range of the damping force applying member 5 is set smaller than the maximum stroke distance of the upper table 3 with respect to the lower table 2.

In the damping seismic isolation table 1 of the present embodiment configured as described above, the lower table 2 is installed on the floor surface of a building or a vehicle, while the upper table 3 is provided with precision instruments, works of art, etc. It is used by placing the seismic isolation target of.

When vibration acts on the floor surface due to, for example, transportation or an earthquake, the vibration of the floor surface propagates to the seismic isolation target through the lower table 2 and the upper table 3, and the seismic isolation target also vibrates. Will be done. However, as described above, the upper table 3 can freely vibrate in the X direction and the Y direction with respect to the lower table 2, and the upper table 3 is independent of the amplitude and cycle of the vibration of the lower table 2. It is possible to vibrate. Therefore, the upper table 3 on which the seismic isolation target is mounted is in a state of being cut off from the vibration of the lower table 2, and is not restricted by the vibration of the floor surface and vibrates in a longer cycle than the vibration. It is possible. This makes it possible to effectively prevent damage to the seismic isolation target object due to vibration of the floor surface.

FIG. 5 is a schematic view showing a state in which the upper table 3 is moved with respect to the lower table 2. In the figure, the two-dot chain line shows the upper table 3 and the upper track rail 41 fixed to the upper table 3. A circle indicated by a chain line in the lower table 2 indicates a movable range of the damping force imparting member 5 on the lower table, and a circle indicated by a chain line in the upper table 3 indicates the upper part. The respective movable ranges of the damping force imparting member 5 on the table 3 are shown. In this way, when the upper table 3 moves with respect to the lower table 2, the damping force imparting member 5 moves by about 1/2 of the moving amount of the upper table 3 and the upper table 3 and the lower table. Move while sliding on 2.

Therefore, when the upper table 3 vibrates in the X direction and the Y direction with respect to the lower table 2, between the upper friction plate 51 of the damping force imparting member 5 and the upper table 3, and between the lower friction plate 50. A frictional resistance is generated both between the lower table 2 and the lower table 2, and the frictional resistance acts as a force for stopping the movement of the upper table 3 with respect to the lower table 2. This damps the vibration of the upper table 3 with respect to the lower table 2.

That is, when the upper table 3 vibrates with respect to the lower table 2, the vibration is damped by the damping force imparting member 5 housed between the lower table 2 and the upper table 3, and the vibration is applied from the floor surface. As soon as the vibration acting on the lower table 2 subsides, the vibration of the upper table 3 relative to the lower table 2 can be settled at an early stage.

Since the damping force applying member 5 exerts a force for stopping the movement of the upper table 3 with respect to the lower table 2, the damping force applying member 5 enhances the static rigidity of the upper table 3 with respect to the lower table 2. Exert function. Therefore, it is possible to arbitrarily set the initial rigidity of the seismic isolation table 1 by changing the friction member 56 and the spring coefficient of the elastic member 52, and the upper table can be operated by a slight force. It is possible to overcome the problem that 3 is displaced with respect to the lower table 2.

Further, since the damping force applying member 5 is housed in the gap between the lower table 2 and the upper table 3, the damping seismic isolation table 1 can be made extremely compact. In particular, it is possible to easily add even to a conventional seismic isolation table that does not have a damping element for the input vibration, and the upper table 3 is replaced by the lower table 2 against the input of excessive vibration. It is possible to prevent the upper table 3 from vibrating with the maximum amplitude and appropriately control the behavior of the upper table 3.

DESCRIPTION OF SYMBOLS 1... Seismic isolation table, 2... Lower table, 3... Upper table, 4... Guide device, 5... Damping force application member, 50... Upper friction plate, 51... Lower friction plate, 52... Elastic member

Claims (5)

A lower table installed on the fixed part,
An upper table with seismic isolation target,
The upper table is freely guided in the X direction and the Y direction orthogonal to the lower table, and the upper table is relatively opposed to the lower table in the Z direction orthogonal to the X direction and the Y direction. And a guide member that holds it immovably,
A damping force applying member that exerts frictional damping on the movement of the upper table with respect to the lower table,
The damping force applying member,
A lower friction plate in contact with the lower table,
An upper friction plate that is in contact with the upper table and is vertically movable with respect to the lower friction plate;
An elastic member that is provided between the lower friction plate and the upper friction plate, presses the lower friction plate toward the lower table and presses the upper friction plate toward the upper table,
A locking bolt that penetrates the lower friction plate and is screwed into the upper friction plate, and adjusts the distance between the lower friction plate and the upper friction plate according to the fastening amount.
Equipped with
The seismic isolation table, wherein the damping force applying member moves relative to both the lower table and the upper table as the upper table moves relative to the lower table. The upper friction plate includes a piston, while the lower friction plate includes a cylinder on which the piston slides, and the upper friction plate is vertically movably held with respect to the lower friction plate. The seismic isolation table described in item 1. A movable range of the damping force applying member is set between the lower table and the upper table, and a diameter of the movable range is set to be smaller than a maximum stroke distance of the upper table with respect to the lower table. The seismic isolation table according to claim 1. The upper table on which the seismic isolation target is mounted is applied to a seismic isolation table that can move freely in the horizontal direction with respect to the lower table installed in the fixed part, and is housed between the lower table and the upper table. A damping force applying member,
A lower friction plate in contact with the lower table,
An upper friction plate that is in contact with the upper table and is vertically movable with respect to the lower friction plate;
An elastic member that is provided between the lower friction plate and the upper friction plate, presses the lower friction plate toward the lower table and presses the upper friction plate toward the upper table,
A locking bolt that penetrates the lower friction plate and is screwed into the upper friction plate, and adjusts the distance between the lower friction plate and the upper friction plate according to the fastening amount.
Equipped with
A damping force imparting member that moves relative to both the lower table and the upper table as the upper table moves with respect to the lower table. While with the upper friction plate piston, the lower friction plate includes a cylinder in which the piston slides, the upper friction plate is characterized that you held vertically movably with respect to the lower friction plate The damping force applying member according to claim 4.

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