JP2024013614A - Seismic isolator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seismic isolator which can widely optimize an attenuation force exerted by a damper to a quake having a variety of magnitudes reaching small/medium-scale earthquakes from a huge earthquake, and can reduce response acceleration generated at an earthquake isolation object as much as possible.

SOLUTION: A seismic isolator comprises: a fixed part; a movable part on which a seismic isolation object is placed, and which is arranged on the fixed part; a support guide mechanism for allowing the movement of the movable part to the fixed part in a horizontal direction, and including a raceway member and a moving block which reciprocates along the raceway member; a damper unit for exerting a reaction force to the movement of the movable part to the fixed part; and an elastic restoration member for restoring the movable part to an initial position on the fixed part. The damper unit is constituted of a first damper arranged at the fixed part, and a second damper which is set smaller than the first damper in an attenuation force and a maximum movable amount, arranged between the first damper and the movable part, and connects the first damper and the movable part.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a seismic isolation device that effectively acts on everything from slight vibrations to large earthquakes.

Seismic isolation devices are known as devices that protect precision equipment and buildings from earthquake motion. Such a seismic isolation device generally has a fixed part installed on the floor or the ground, a movable part where the seismically isolated object such as precision equipment or a building is placed, and a part between the fixed part and the movable part. An isolator and a damper are provided.

The isolator enables the movable part to separate from the fixed part and vibrate freely when vibration energy is transmitted from the fixed part to the movable part, and makes the vibration of the movable part longer. to reduce the response acceleration of the seismically isolated object. Further, the damper absorbs the vibration energy transmitted to the movable part, and quickly converges the vibration of the movable part whose period has been increased by the isolator.

In such a seismic isolation device, when the damping force of the damper is increased in response to the seismic motion of a large earthquake exceeding seismic intensity 5 or above, the resistance force exerted by the damper against the free vibration of the movable part also increases. As a result, the isolator does not function sufficiently against microtremors associated with, for example, small- to medium-sized earthquakes, and it becomes impossible to reduce the response acceleration of the seismically isolated object to the earthquakes. On the other hand, if the damping force of the damper is set in response to small earthquake motions, the displacement of the movable part becomes excessive in response to large earthquake motions, and there is a concern that the movable part may interfere with surrounding structures. , it is also difficult to bring the vibrations of the movable part to an early end.

As a solution to such problems, Patent Document 1 discloses a seismic isolation device using elastic sliding bearings. This elastic sliding bearing is a combination of an elastic bearing made of laminated rubber and a sliding bearing, and when a slight tremor is applied to the movable part due to a small or medium-sized earthquake, the lateral vibration is absorbed by the laminated rubber. It is configured so that it can be released by deformation. In addition, when a large earthquake causes a large vibration that exceeds the predetermined amount of deformation of the laminated rubber and acts on the movable part, the sliding material provided integrally with the laminated rubber slides on the fixed part, causing the laminated rubber to deform. It is designed to handle earthquakes of a magnitude that is difficult to handle.

JP2009-281559

For example, in the field of precision processing such as semiconductor manufacturing, the response acceleration generated in a seismically isolated object must be sufficiently suppressed not only for large vibrations associated with large earthquakes, but also for microtremors generated in small and medium-sized earthquakes. It is necessary to reduce this to prevent any negative effects on product processing.

However, the elastic bearings and sliding bearings used in seismic isolation devices are mechanisms that have both the isolator function and the damper function, and while the isolator function is highly demonstrated, the damper function is limited. It was difficult to do.

The present invention has been developed in view of these problems, and its purpose is to detect earthquake motions of various sizes, from large-movable seismic motions caused by gigantic earthquakes to microtremors caused by small and medium-sized earthquakes. It is an object of the present invention to provide a vibration isolation device that can widely optimize the damping force exerted by a damper against vibrations, and can reduce as much as possible the response acceleration generated in an object to be vibration-isolated.

The seismic isolation device of the present invention includes a fixed part, a movable part on which an object to be isolated is placed and arranged on the fixed part, and a movable part that allows horizontal movement of the movable part with respect to the fixed part. , a support guide mechanism including a track member and a moving block that reciprocates along the track member, a damper unit that exerts a reaction force against the movement of the movable part with respect to the fixed part, and a damper unit that moves the movable part to an initial position on the fixed part. an elastic restoring member for restoring the damper unit, the damper unit includes a first damper disposed relative to the fixed part, and a damping force and a maximum movable amount set to be smaller than that of the first damper; A second damper is disposed between the first damper and the movable part and connects the first damper and the movable part.

According to the present invention, the damping force exerted by the damper can be applied over a wide range of vibrations of various sizes, from large-movable seismic motions caused by large earthquakes to microtremors caused by small and medium-sized earthquakes. It becomes possible to reduce the response acceleration generated in the vibration-isolated object as much as possible.

1 is a schematic plan view showing a first embodiment of a seismic isolation device to which the present invention is applied. FIG. 2 is a perspective view showing an example of a linear guide that can be used as a support guide mechanism. FIG. 3 is a cross-sectional view showing an example of a viscous damping damper that can be used as a first damper. FIG. 3 is a perspective view showing a ball spline device that can be used as a second damper. FIG. 3 is a schematic plan view showing a state in which the movable part of the seismic isolation device shown in the embodiment has started moving in the X+ direction. FIG. 3 is a schematic plan view showing a state in which the movable part of the seismic isolation device shown in the embodiment has moved in the X+ direction to the maximum movable range of the second damper. FIG. 7 is a schematic plan view showing a state in which the movable part has further moved in the X+ direction from the state shown in FIG. 6; 8 is a schematic plan view showing a state in which the movable part starts moving in the X-direction from the state shown in FIG. 7. FIG. 8 is a schematic plan view showing a state in which the movable part has further moved in the X-direction from the state shown in FIG. 7. FIG. It is a perspective view showing a second embodiment of a seismic isolation device to which the present invention is applied. It is a perspective view showing the state where a movable part and one second damper are removed from a seismic isolation device concerning a second embodiment.

Hereinafter, the seismic isolation device of the present invention will be explained in detail using the accompanying drawings.

FIG. 1 is a schematic plan view showing a first embodiment of a seismic isolation device 1 to which the present invention is applied. The seismic isolation device 1 of the first embodiment includes a fixed part 2 installed on a floor surface or the ground, a movable part 3 in which a seismically isolated object such as a precision instrument or a building is placed, and a fixed part 2 attached to the fixed part 2. A support guide mechanism 4 serving as an isolator that guides the movement of the movable part 3 in the horizontal direction (arrow X direction in FIG. 1), and a damper unit that exerts a reaction force against the movement of the movable part 3 in the X direction. 5, and an elastic restoring member 6 for returning the movable part 3 to the initial position on the fixed part 2.

For example, if the object to be seismically isolated is a precision instrument or a work of art, the fixing part 2 is a fixed table installed on the floor of a building or a loading platform. It is a building foundation installed against the ground.

Further, if the seismically isolated object is a precision instrument, a work of art, etc., the movable part 3 is a movable table supported by the fixed table via the support guide mechanism, and If the object is a building, it is a sturdy movable frame supported on the building foundation via the support and guide mechanism.

As the support guide mechanism 4, for example, a linear guide 40 as shown in FIG. 2 can be used. This linear guide 40 includes a track member 41 that is laid along the X direction on the fixed part 2 and has rolling surfaces 41a for balls and rollers formed along the longitudinal direction, and rolling elements that circulate endlessly inside. The moving block 42 has rows and can freely reciprocate along the track member 41. The movable part 3 is fixed to the movable block 42, and when the movable block 42 reciprocates along the track member 41, the movable part 3 also moves on the fixed part 2 together with the movable block 42 in the X direction.

Note that the support guide mechanism 4 is not limited to the linear guide 40 shown in FIG. 2 as long as it can ensure free linear reciprocating movement of the movable part 3 with respect to the fixed part 2.

On the other hand, the damper unit 5 is composed of a combination of a first damper 50 and a second damper 51. The first damper 50 is provided corresponding to the movable range of the movable part 3 on the fixed part 2, that is, the movable range of the movable part by the support and guide mechanism, and is designed to accommodate large earthquakes with large amplitudes and large vibration energy. It corresponds to earthquake motions such as On the other hand, the second damper 51 is provided between the first damper 50 and the movable part 3, and connects the first damper 50 and the movable part 3. It responds to minute vibrations such as traffic vibrations, wind swaying of buildings, etc.

As the first damper 50, it is possible to use, for example, a viscous damping damper 70 as shown in FIG. This viscous damping damper 70 includes a screw shaft 71 that is provided on the fixed part so that its axial direction coincides with the X direction and has a spiral thread groove formed on its outer peripheral surface, and a cylinder that the screw shaft 71 passes through. a damper body 72 that is formed in a shape and reciprocates along the screw shaft 71; a rotor 73 that is rotatably held inside the damper body 72; A nut member 74 is screwed onto the threaded shaft 71 via a ball and fixed to the axial end of the rotor 73. Further, a viscous fluid is filled between the inner peripheral surface of the damper main body 72 and the outer peripheral surface of the rotor 73.

The screw shaft 71 and the nut member 74 constitute a so-called ball screw device, and when the damper main body 72 moves on the fixed part 2 in the axial direction of the screw shaft 71, the screw shaft 71 rotates around the screw shaft 71. The nut member 74 rotates, and the rotation is transmitted to the rotor 73. That is, when the damper main body 72 performs a linear reciprocating motion along the screw shaft 71, the rotor performs a rotational reciprocating motion inside the damper main body, and the shear resistance force corresponding to the rotational speed of the rotor increases the viscosity. The fluid acts on the rotor.

The shear resistance force acting on the rotor 73 from the viscous fluid becomes a reaction force against the rotational reciprocating motion of the rotor 73, and is converted into a reaction force against the linear reciprocating motion of the damper body 72 in the X direction through conversion by a ball screw device. Become. This makes it possible to attenuate the energy that moves the damper main body 72 in the X direction.

The viscous damper shown in FIG. 3 is merely an example of a damper that can be used as the first damper 50, and the present invention is not limited thereto. That is, as the first damper 50, various types of dampers can be selected depending on the required movable range and the magnitude of damping force.

On the other hand, the second damper 51 is coupled to a guide shaft 81 that is provided so that its axial direction coincides with the X direction with respect to the movable part 3, and a damper body 72 of the first damper 50, and the guide shaft 81, and a sliding member 82 that moves along a line 81.

In this first embodiment, a ball spline device 80 shown in FIG. 4 is used as the second damper. A rolling groove 81a for rolling elements is provided along the axial direction on the outer peripheral surface of the guide shaft 81, and the sliding member 82 is assembled to the guide shaft 81 via an endlessly circulating row of rolling elements. ing. By rolling the rolling elements on the rolling grooves 81a of the guide shaft 81, the sliding member 82 can reciprocate along the guide shaft 81 with extremely small movement resistance. On the other hand, by arbitrarily adjusting the magnitude of the preload applied to the rolling elements interposed between the guide shaft 81 and the sliding member 82, the movement resistance of the sliding member 82 with respect to the guide shaft 81 can be reduced. It is possible to increase or decrease it arbitrarily. In this sense, the ball spline device 80 functions as a damper with extremely small damping force.

Note that the ball spline shown in FIG. 4 is merely an example of a device that can be used as the second damper 51, and is not limited thereto. Various types of dampers can be selected depending on the movable range required of the second damper 51 and the required magnitude of damping force.

Both ends of the guide shaft 81 are fixed to the movable part 3 by a pair of support members, and the sliding member 82 coupled to the first damper 50 is connected to the guide shaft 81 only between the pair of support members. can be moved along. In this way, the damper unit 5 has a structure in which the first damper 50 is connected to the movable part 3 via the second damper 51. In other words, the damper unit 5 has a structure in which the first damper 50 is connected to the movable part 3 through the second damper 51. It has a structure in which the first damper 50 and the second damper 51 are provided in series. The damping force exerted by the second damper 51, that is, the magnitude of the reaction force exerted on the linear reciprocating motion of the movable part 3, is set to be smaller than the damping force exerted by the first damper 50. .

Further, the first damper 50 is configured to exert damping force over substantially the entire range of movement of the movable part 3, but the second damper 51 is configured to damp only within a narrower range than the first damper 50. It is designed to exert power. That is, the maximum movable amount of the second damper 51 is set smaller than that of the first damper 50.

Therefore, when the movable part 3 moves in the X direction, the second damper 51 operates before the first damper 50 in the damper unit 5, and the amount of movement of the movable part 3 corresponds to the movement of the second damper 51. When the range is exceeded, the first damper 50 operates.

The elastic restoring member 6 includes a first restoring member 61 provided between the damper main body 72 of the first damper 50 and the fixed part 2, and a first restoring member 61 provided between the movable part 3 and the fixed part 2. and two restoring members 62. The first restoring member 61 functions to return the first damper 50 to its initial position before operation after the vibration transmitted to the movable part 3 has subsided. Further, the second restoring member 62 functions to return the movable part 3 to the initial position before operation after the vibration transmitted to the movable part 3 has subsided.

The seismic isolation device 1 of the first embodiment configured as described above operates as follows.

For example, when a vibration acts on the fixed part 2 due to an earthquake, the movable part 3 is separated from the fixed part 2 by the action of the support guide mechanism 4, and there is no space between the fixed part 2 and the movable part 3. A relative linear reciprocating motion in the X direction occurs. As shown in FIG. 5, first, when the movable part 3 starts moving in the X+ direction with respect to the fixed part 2, only the second damper 51, which has a smaller damping force than the first damper 50, operates; The first damper 50 does not operate. That is, in the first damper 50, the damper main body 72 does not move relative to the screw shaft 71, and in the second damper 51, the sliding member 82 moves relative to the guide shaft 81.

Therefore, if the amplitude of the vibration generated in the movable part 3 is within the movable range of the second damper 51, in this seismic isolation device 1, the second damper 51 is moved without operating the first damper 50. The second damper 51 absorbs the vibration energy transmitted from the fixed part 2 to the movable part 3, and quickly converges the vibration of the movable part 3.

In addition, since the damping force of the second damper 51 is set smaller than that of the first damper 50, it can be used as an isolator to support and guide even against small and medium-sized earthquakes, wind vibrations of buildings, and micro-tremors such as traffic vibrations. By sufficiently operating the mechanism 4, it becomes possible to isolate the movable part 3 from the vibrations of the fixed part 2. Therefore, this seismic isolation device 1 can sufficiently reduce the response acceleration generated in the seismically isolated object mounted on the movable part 3 even in the case of slight vibrations, and is suitable for use in precision processing equipment such as semiconductor manufacturing equipment, for example. Effective for earthquake countermeasures.

On the other hand, when the movable part 3 moves in the X+ direction beyond the movable range of the second damper 51 due to vibrations generated in the movable part 3, the second damper 51 slides as shown in FIG. Since the member 82 hits the support member that supports the guide shaft 81, when the movable part 3 moves further in the X+ direction, the first damper 50 operates from this point. That is, as shown in FIG. 7, the damper main body 72 of the first damper 50 coupled to the sliding member 82 of the second damper 51 moves relative to the screw shaft 71, and the first damper 50 moves to the fixed part. The vibration energy transmitted from the movable part 2 to the movable part 3 is absorbed to converge the vibration of the movable part 3.

Thereafter, when the moving direction of the movable part is reversed from the X+ direction to the X- direction, as shown in FIG. Only the small second damper 51 operates. At this time, the first damper 50 does not operate, and the damper body 72 of the first damper 50 remains at the position on the screw shaft 71 when the moving direction of the movable part 3 is reversed.

Then, when the movable part 3 further moves in the X-direction and the sliding member 82 of the second damper 51 hits the support member supporting the guide shaft 81, the first damper 50 operates from this point. That is, as shown in FIG. 9, the damper body 72 of the first damper 50 moves in the X-direction with respect to the screw shaft 71 with the sliding member of the second damper 51 abutting against the support member of the guide shaft. The first damper 50 absorbs the vibration energy transmitted from the fixed part 2 to the movable part 3 and converges the vibration of the movable part 3.

As described above, in the seismic isolation device 1 of the first embodiment, when a large amount of seismic motion acts on the fixed part 2 due to a large earthquake, for example, the movable part 3 moves against the fixed part 2 in the second direction. When moving beyond the movable range of the damper 51, the first damper that exerts a larger damping force than the second damper 51 operates. As a result, even if huge seismic energy of a major earthquake is transmitted to the movable part, the maximum displacement of the movable part can be suppressed by the large damping force exerted by the first damper. This makes it possible to bring the tremors of No. 3 to an end quickly.

Next, a second embodiment of a seismic isolation device to which the present invention is applied will be described.

FIG. 10 shows a seismic isolation device according to a second embodiment. The seismic isolation device 1A of the second embodiment supports the movable part 3 on the fixed part 2 via the support guide mechanism 4, as in the first embodiment, and the movable part 3 supports the fixed part 3. 2 along the X direction. As the support guide mechanism 4 of this second embodiment, the linear guide 40 shown in FIG. 2 can be used. In the example shown in FIG. 10, the track member 41 is attached to the fixed part 2 along the X direction. A moving block 42 that is laid and slides on the track rail 41 is fixed to the movable part.

A damper unit 5 is provided between the fixed part 2 and the movable part 3. The damper unit 5 includes a combination of a first damper 50 and a pair of second dampers 51. The first damper 50 is provided corresponding to the movable range of the movable part 3 on the fixed part 2, that is, the movable range of the movable part by the support guide mechanism 4, while the second damper 51 is provided corresponding to the movable range of the movable part on the fixed part 2. 50 and the movable part 3, and connects the first damper 50 and the movable part 3.

FIG. 11 is a perspective view showing a state in which one of the movable part 3 and the second damper 51 is removed to expose the first damper 50. The first damper 50 includes a rack 52 fixed along the X direction with respect to the fixed part 2, a pinion gear 53 that meshes with the rack 52 and rotates, and is rotated by the pinion gear 53, and is rotated by the second damper. 51, and a rotary damper 54 fixed to the rotary damper 51. The rack 52 is installed on the fixed part 2 in a manner corresponding to the movement range of the movable block 42 of the support guide mechanism 4. The rotary damper 54 is filled with viscous fluid, and is configured to exert a damping force on the rotational movement when it is inputted from the pinion gear 53.

On the other hand, as shown in FIG. 11, the second damper includes a sliding member 55 fixed to the movable part 3, and this sliding member 55 is assembled via a large number of rolling elements, and the sliding member 55 is assembled along the X direction. a guide shaft 56 provided on the guide shaft 56; an intermediate plate 57 on which the guide shaft 56 is placed; and a pair of locking members 58 provided on the intermediate plate 57 corresponding to both ends of the guide shaft 56 in the longitudinal direction. It is equipped with. The intermediate plate 57 is suspended from the movable part 3 via the sliding member 55 and the guide shaft 56, and when the guide shaft 56 moves in the X direction with respect to the sliding member 55, The intermediate plate 57 is movable in the X direction with respect to the movable part 3. However, since the guide shaft 56 is set shorter than the length of the track rail 41 of the support guide mechanism 4, the moving range of the movable part 3 with respect to the intermediate plate 57 is smaller than the movement range of the movable part 3 with respect to the fixed part 2. The movement range of No. 3 is set short.

The combination of the sliding member 55 and the guide shaft 56 functions as a damper with extremely small damping force, similar to the ball spline device in the first embodiment. That is, by arbitrarily adjusting the magnitude of the preload applied to the rolling elements interposed between the sliding member 55 and the guide shaft 56, the movement resistance of the sliding member 55 with respect to the guide shaft 56 can be adjusted arbitrarily. It is possible to increase or decrease the amount.

The rotary damper 54 is fixed to the back surface of the intermediate plate 57, that is, the surface opposite to the surface on which the guide shaft 56 is installed. Therefore, when the intermediate plate 57 moves relative to the fixed part 2, the pinion gear 53 that meshes with the rack 52 rotates, and the rotary damper 54 exerts a damping force, and this damping force is applied to the It will act on movement in the direction.

Although not shown in FIGS. 10 and 11, an elastic restoring member made of, for example, a coil spring is provided between the movable part 3 and the fixed part 2, and A biasing force is applied in a direction to return the movable part 3 that has vibrated in the direction to the center position of the vibration amplitude. Further, a similar elastic restoring member is provided between the fixing part 2 and the intermediate plate 57, and applies an urging force in the direction of returning the intermediate plate 57 to its initial position on the fixing part.

The seismic isolation device of the second embodiment configured as above operates as follows.

For example, when vibration acts on the fixed part 2 due to the occurrence of an earthquake, the movable part 3 supported by the support guide mechanism 4 as an isolator moves in the X direction with respect to the fixed part 2, and the fixed part A reciprocating motion will occur on 2. If the amplitude of the reciprocating motion of the movable part 3 at this time is within the movable range of the second damper 51, that is, within the movable range of the sliding member 55 with respect to the guide shaft 56, the Only the weak damping force of the second damper 51 acts. At this time, the intermediate plate 57 is in a substantially stationary state on the fixing portion 2.

As a result, as in the first embodiment described above, the second damper 51 absorbs the seismic energy transmitted from the fixed part 2 to the movable part 3 in response to small and medium-sized earthquakes, wind vibrations of buildings, and small vibrations such as traffic vibrations. As a result, the vibration of the movable part 3 is brought to an early end. Further, since the damping force of the second damper 51 is smaller than that of the first damper 50, the support guide mechanism 4 as an isolator can be sufficiently operated, and the seismically isolated object mounted on the movable part 3 can be This makes it possible to sufficiently reduce the response acceleration that occurs.

On the other hand, when the amplitude of the reciprocating motion of the movable part 3 exceeds the movable range of the second damper 51, the movable part 3 hits the locking member 58 provided on the intermediate plate 57, and the intermediate plate It moves on the fixed part 2 together with the movable part 3 in the X direction so as to be dragged by the movable part 3.

As a result, in the first damper 50, the rotary damper 54 moves in the X direction with respect to the fixed part 2, so the pinion gear that meshes with the rack rotates, causing the intermediate plate 57 to move in the X direction. The damping force of the rotary damper 54 acts on this. Since the intermediate plate 57 is dragged by the movable part 3 and moves in the X direction, the damping force exerted by the rotary damper 54 acts on the movement of the movable part 3 in the X direction.

In this way, also in the seismic isolation device 1A of the second embodiment shown in FIG. When moving beyond the movable range of the second damper 51, the first damper 50 that exerts a larger damping force than the second damper 51 operates, and the large damping force exerted by the first damper 50 operates. This not only makes it possible to suppress the maximum displacement of the movable part 3, but also allows the vibration of the movable part 3 to converge at an early stage.

As explained above, according to the seismic isolation devices of the first and second embodiments, two types of dampers having different damping forces and maximum movable ranges are connected in series between the fixed part 2 and the movable part 3. By connecting, it is possible to sufficiently reduce the response acceleration generated in the seismically isolated object mounted on the movable part against small and medium-sized earthquakes, minute vibrations caused by wind shaking of buildings, traffic vibrations, etc. It is also effective against large amounts of movement and large-energy vibrations associated with earthquakes, and widely optimizes the damping force exerted by the damper against various types of vibrations, reducing the response acceleration generated in the seismically isolated object as much as possible. becomes possible.

Moreover, by setting the damping force exerted by the second damper 51 to an arbitrary magnitude, it becomes possible to optimize the seismic isolation device for various uses.

In addition, in the embodiment of the present invention shown in the figures, the case where the movable part vibrates only in the X direction has been described as an example, but the case where the movable part vibrates in the X direction and the seismic isolation device that is orthogonal to the X direction are explained. By stacking seismic isolation devices that vibrate in the Y direction, it is also possible to create a seismic isolation device that operates within a horizontal two-dimensional plane.

DESCRIPTION OF SYMBOLS 1... Seismic isolation device, 2... Fixed part, 3... Movable part, 4... Support guide mechanism, 5... Damper unit, 6... Elastic restoring member, 50... First damper, 51... Second damper

Claims (4)

A fixed part,
a movable part on which a seismically isolated object is placed and placed on the fixed part;
a support guide mechanism that allows horizontal movement of the movable part with respect to the fixed part and includes a track member and a moving block that reciprocates along the track member;
a damper unit that exerts a reaction force against the movement of the movable part with respect to the fixed part;
an elastic restoring member that returns the movable part to the initial position on the fixed part,
The damper unit is
a first damper disposed relative to the fixed part;
a second damper whose damping force and maximum movable amount are set smaller than those of the first damper, and which is disposed between the first damper and the movable part and connects the first damper and the movable part; A seismic isolation device comprising: The seismic isolation device according to claim 1, wherein the first damper operates only when the amount of movement of the movable portion exceeds the maximum amount of movement of the second damper. The damper according to claim 1, wherein the second damper includes a guide shaft disposed parallel to the track member of the support guide mechanism, and a sliding member that moves along the guide shaft. Seismic device. 4. The seismic isolation device according to claim 3, wherein the first damper operates when the movable part moves beyond a movable range of the sliding member relative to the guide shaft of the second damper.

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