JP2009068556A - Base isolation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate setting of the frictional force of friction members 61, 62 and a base isolation cycle determined by an elastic member 51 at desired target values, or the like. <P>SOLUTION: In the base isolation device 10, a support section 20 which supports the weight of an object to be base-isolated 1 while allowing horizontal movement of the object to be base-isolated 1, and a friction damper section 30 for suppressing the horizontal movement of the object to be base-isolated 1 are arranged in parallel with each other in a vertical gap G between the object to be base-isolated 1 and a lower structure 3 below. The friction damper section 30 includes the pair of vertically-disposed friction members 61, 62 which slide horizontally in response to relative horizontal displacement of the object to be base-isolated 1 and the lower structure 3, the elastic member 51 having upper and lower ends which relatively displace horizontally according to horizontal force, a disk spring 42 arranged in series with the pair of friction members 61, 62 so as to apply vertically pressing force to the friction members 61, 62, and a control mechanism 44 for controlling the pressing force by adjusting the amount of deflection of the disk spring 42. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an isolation device that protects an isolation object such as a building from an earthquake or the like.

Isolation devices that protect buildings from earthquakes and the like are widespread. This vibration isolator is generally interposed between a building and its foundation.
As an example of the vibration isolator, Patent Document 1 discloses a configuration in which laminated rubber is arranged in series under a pair of upper and lower friction plates. According to this configuration, for an earthquake of a medium scale or larger, the pair of friction plates slide in the horizontal direction to dampen the vibration, and the frictional force at the time of sliding is reduced by the vibration damping force of the building. On the other hand, for small-scale earthquakes where the friction plates do not slide with each other, the laminated rubber is deformed in the horizontal direction, so that the vibration of the building is extended to the desired vibration-isolating period and is immunized. While shaking, the vibration energy is absorbed to attenuate the vibration (see Patent Document 1).
JP-A-9-310408

  Here, as can be seen from the fact that the magnitude of the friction force of the friction plate of Patent Document 1 is calculated as the product of the normal force of the sliding surface and the friction coefficient, it depends on the support load of the vibration isolator. Change. Further, the vibration isolation period due to the laminated rubber also changes according to the supporting load in the same manner because the horizontal rigidity of the laminated rubber can change depending on the supporting load.

  However, it is generally difficult to calculate the support load of the vibration isolator. This is because a plurality of vibration isolation devices are usually arranged in parallel with respect to a building, and the magnitude of the support load assigned to each vibration isolation device varies depending on the planar position in the building. Therefore, it is very difficult to grasp the supporting load for each vibration isolator, and as a result, it is very difficult to set the frictional force and vibration isolation cycle of each vibration isolator to the desired target value. .

  Furthermore, even if the magnitude of the support load is grasped and the frictional force and the vibration isolation period of each vibration isolator can be set to the target values, the building will be subjected to rocking vibration (the building will move up and down like a cradle). If the rocking vibration occurs, the supporting load of each vibration isolator varies due to the rocking vibration, and it is difficult to maintain the frictional force and the vibration isolation cycle at the target values. It was.

  The present invention has been made in view of such a conventional problem. A pair of upper and lower friction members and a pair of friction members are arranged in series, and the upper end and the lower end are relatively displaced in the horizontal direction in response to a horizontal force. The present invention provides a vibration isolator having an elastic body that easily sets and maintains the frictional force of the friction member and the vibration isolation period of the elastic body at a desired target value. With the goal.

In order to achieve this object, the vibration isolator shown in claim 1 is:
A support portion that supports the weight of the vibration isolation object while allowing horizontal movement of the vibration isolation object, and a friction damper that suppresses horizontal movement of the vibration isolation object include the vibration isolation object and its lower part. A vibration isolator which is interposed in parallel with the vertical gap between the lower structure and
The friction damper part is
A pair of upper and lower friction members that slide in the horizontal direction according to the relative displacement in the horizontal direction between the object to be isolated and the lower structure;
An elastic body that is arranged in series with the pair of friction members and has an upper end and a lower end that are relatively displaced in the horizontal direction in response to a horizontal force;
A disc spring disposed in series with respect to the pair of friction members and imparting a vertical pressure contact force to the pair of friction members;
And an adjusting mechanism for adjusting the magnitude of the pressing force by adjusting the amount of deflection of the disc spring.

  According to the first aspect of the present invention, first, the weight of the object to be isolated is supported by the support part and not by the friction damper part. Is determined based on the coefficient of friction between the friction members and the pressure contact force of the disc spring. The friction coefficient of the friction member is known, and the pressure contact force of the disc spring can be adjusted by the adjusting mechanism, so that the friction force of the friction damper portion can be easily set to an intended target value.

  Further, when the pressure contact force is transmitted to the elastic body, the magnitude of the pressure contact force can be adjusted by the disc spring, so that the horizontal rigidity of the elastic body can be set to a predetermined value, and It is possible to easily set the vibration isolation period by the friction damper portion to a desired target value.

  Furthermore, even if rocking vibration occurs in the vibration isolation object during an earthquake, the weight of the vibration isolation object is generally supported by the support part, so that the friction damper part has a load fluctuation due to rocking vibration. The influence hardly appears, that is, since the fluctuation of the pressure contact force is small, the friction force and the vibration isolation period of the friction damper part are also maintained at the target values.

Invention of Claim 2 is the vibration isolator of Claim 1, Comprising:
An auxiliary friction damper is provided in parallel with the elastic body,
The magnitude of the frictional force when the auxiliary friction damper slides in the horizontal direction is smaller than the magnitude of the frictional force when the pair of friction members slide in the horizontal direction,
When the auxiliary friction damper does not slide, the auxiliary friction damper restrains the relative displacement in the horizontal direction between the upper end and the lower end of the elastic body to be impossible.

  According to the second aspect of the present invention, it is possible to effectively prevent the object to be isolated from vibrating in the horizontal direction only by applying a small horizontal force such as a wind load. Details are as follows.

  If a horizontal force larger than the frictional force of the pair of friction members does not act, the vibration isolating object does not move in the horizontal direction based on the pair of friction members, but on the other hand, the elastic body is not elastically deformed. Based on this, there is a possibility that the vibration isolating object easily moves in the horizontal direction even with a horizontal force smaller than the frictional force. That is, if the pair of friction members and the elastic body are simply arranged in series, there is a possibility that the object to be isolated will vibrate in the horizontal direction even with a small horizontal force such as a wind load.

  However, here, the above-described vibration isolator is provided with an auxiliary friction damper, and this auxiliary friction damper causes a relative displacement in the horizontal direction between the upper end and the lower end of the elastic body until the auxiliary friction damper starts to slide. Restrained impossible. And the magnitude | size of the frictional force at the time of sliding is set smaller than the magnitude | size of the frictional force at the time of a pair of said friction member sliding. Therefore, it is possible to effectively prevent the building from vibrating in the horizontal direction only by applying a small horizontal force such as a wind load.

Invention of Claim 3 is the vibration isolator of Claim 2, Comprising:
The pair of friction members and the elastic body are connected vertically.
The auxiliary friction damper includes an auxiliary friction member provided in one of the pair of friction members so as to be slidable in a horizontal direction, and is arranged in series with the auxiliary friction member so as to be perpendicular to the auxiliary friction member. And a spring member for applying a pressure contact force in the direction.
According to the third aspect of the present invention, since one friction member of the pair of friction members is also used as a component of the auxiliary friction damper, one auxiliary friction member of the auxiliary friction damper can be reduced. As a result, cost can be reduced.

Invention of Claim 4 is the vibration isolator in any one of Claim 1 thru | or 3, Comprising:
The elastic body is a viscoelastic body.
According to the fourth aspect of the present invention, the vibration energy of the object to be isolated is reduced by the energy absorbing action accompanying the shear deformation of the viscoelastic body itself when the upper end and the lower end of the viscoelastic body are relatively displaced in the horizontal direction. Absorb. Therefore, the damping property of the vibration of the vibration isolation target can be further increased.

The invention shown in claim 5 is the vibration isolator according to any one of claims 1 to 4,
The support member that receives the pressure contact force is not arranged in parallel with the elastic body,
The ratio of the change in the elastic force to the change in the deflection amount of the disc spring is smaller in the deflection amount in the second range than in the first range,
The amount of deflection of the disc spring is adjusted by the adjusting mechanism so as to be within the second range.
According to the fifth aspect of the present invention, the amount of deflection of the disc spring is adjusted to fall within the second range where the rate of change in the elastic force is small. Therefore, even if the size of the vertical gap in which the vibration isolator is interposed changes due to rocking vibration or the like, and the amount of deflection of the disc spring fluctuates due to this, the disc spring in the second range Since the change in the elastic force is small, fluctuations in the pressure contact force of the disc spring can be suppressed, so that the frictional force and the vibration isolation period of the friction damper can be substantially maintained at the target value.

The invention shown in claim 6 is the vibration isolator according to any one of claims 1 to 4,
A holding member that holds the distance between the upper end and the lower end of the elastic body at the natural length of the elastic body while allowing horizontal relative displacement between the upper end and the lower end of the elastic body. It is provided in parallel with the elastic body.
According to the sixth aspect of the present invention, the elastic body is held by the holding member in a natural length state in which the pressure contact force from the disc spring does not act. Therefore, since the horizontal rigidity of the elastic body is maintained at a substantially constant value, the vibration isolation period by the friction damper can be easily set to a desired target value, and rocking vibration can be applied to the vibration isolation object. Even if this occurs, the target value can be maintained.

  According to the vibration isolator according to the present invention, the frictional force of the friction member and the vibration isolation cycle by the elastic body can be easily set and maintained at a desired target value.

  Hereinafter, embodiments of a vibration isolator according to the present invention will be described in detail with reference to the drawings.

<<< Vibration Isolator 10 of First Embodiment >>>
In FIG. 1, the conceptual diagram of the building 1 to which the vibration isolator 10 of 1st Embodiment was applied is shown. The vibration isolator 10 is interposed in the vertical gap G between the building 1 as a vibration isolation object and the foundation 3 as a lower structure below the object 1. In the vertical gap G, a plurality of the above-described vibration isolation devices 10 are arranged in parallel, so that the plurality of vibration isolation devices 10 can reduce the weight of the building 1 at each support position in the plane of the building 1. Supports sharing.

  FIG. 2 is a side sectional view of the vibration isolator 10. The plurality of vibration isolator 10 has the same structure. Further, all of the side cross-sectional views referred to below are shown with some cross-sectional lines omitted to avoid complication of the drawings.

  The vibration isolator 10 supports the weight of the building 1 while allowing the horizontal movement of the building 1, and the friction damper part arranged in parallel to the bearing part 20 to suppress the horizontal movement of the building 1. 30.

  The bearing unit 20 is, for example, a rolling bearing. That is, the smooth rolling plate 23 fixed to the lower surface 1a of the building 1 through the receiving seat 21a, the smooth rolling plate 24 fixed to the upper surface 3a of the foundation 3 through the receiving seat 21b, and these rolling plates 23. , 24 and a plurality of steel balls 25 interposed between the horizontal rolling surfaces. The steel balls 25 roll while receiving the supporting load of the building 1 in the vertical direction via the rolling plates 23 and 24, so that the building 1 can be moved horizontally even with a small horizontal force (horizontal external force). It is supported by.

  Incidentally, according to this rolling support 20, the vertical gap G, which is a gap between the lower surface 1a of the building 1 and the upper surface 3a of the foundation 3, is maintained at a substantially constant interval. In addition, since most of the support load of the building 1 shared by each vibration isolator 10 is received by the support portion 20, the friction damper portion 30 has a pressure contact force based on a disc spring portion 40 described later. Only supports loads.

  On the other hand, the friction damper portion 30 includes a disc spring portion 40, an elastic rubber portion 50, and a friction damping portion 60, which are arranged in series in this order from top to bottom in the vertical direction. In the constituent parts 40, 50, 60, the constituent parts adjacent in the vertical direction are connected and fixed to each other by bolting or the like.

  The friction damping part 60 performs damping of horizontal vibration of the building 1 by the frictional force in the horizontal direction, and includes a pair of upper and lower friction plates 61 and 62 that slide in the horizontal direction on the friction surfaces that are in contact with each other. The lower friction plate 62 is fixed to the upper surface 3a of the foundation 3 of the building 1, while the upper friction plate 61 is superposed on the lower flange plate 53, which is the lower surface of the elastic rubber portion 50, and is bolted. . Therefore, with the relative movement of the upper and lower friction plates 61 and 62 in the horizontal direction, a frictional force is generated on the sliding friction surface, and thereby the horizontal vibration of the building 1 is attenuated. Here, a stainless steel plate is used for the lower friction plate 62, and ultrahigh molecular weight polyethylene is used for the upper friction plate 61. However, these materials are appropriately used based on the order of the magnitude of the required frictional force. Selected. Further, this frictional force changes according to a pressure contact force which is a vertical drag acting on the friction surfaces (hereinafter also referred to as sliding surfaces) of the upper and lower friction plates 61 and 62. This pressure contact force is a disc spring which will be described later. Since it is given by the elastic force of the part 40, the magnitude of the frictional force can be adjusted by adjusting the elastic force.

  The elastic rubber part 50 extends the vibration of the building 1 to an intended vibration isolation period under the action of a small horizontal force that does not allow the pair of upper and lower friction plates 61 and 62 related to the friction damping part 60 to slide. The vibration is damped while being periodic, and the structure thereof is a so-called laminated rubber 51 (for example, a cylindrical elastic body formed by alternately laminating circular steel plates 51a and rubber layers 51b). It is sandwiched and fixed between a pair of upper and lower flange plates 52 and 53. The lower flange plate 53 is overlapped with the upper friction plate 61 that is the upper surface of the friction damper 60 and bolted as described above, while the upper flange plate 52 is the lower pressure plate 46 that is the lower surface of the disc spring portion 40. It is piled up and bolted. Accordingly, the laminated rubber 51 is sheared and deformed in the horizontal direction according to the applied horizontal force, and the upper flange plate 52 at the upper end and the lower flange plate 53 at the lower end are relatively displaced in the horizontal direction. To make the period longer.

  As shown in FIG. 3, the horizontal rigidity Kh (P) of the laminated rubber 51 changes according to the vertical load P acting on the laminated rubber 51, so that the vibration after the long period by the laminated rubber 51 is increased. The period (hereinafter also referred to as the vibration isolation period) also changes according to the load P. In this regard, in the first embodiment, the above-described disc spring portion is arranged in parallel with the laminated rubber 51. Since the support member for receiving the pressure contact force from 40 is not arranged at all, the pressure contact force from the disc spring part 40 acts on the laminated rubber 51 as the above-described vertical load P as it is. Therefore, the vibration isolation period by the laminated rubber 51 can also be adjusted by adjusting the resilience of the disc spring part 40 in the same manner as the frictional force of the friction damping part 60 described above.

  As described above, the Belleville spring portion 40 adjusts and applies a vertical pressure contact force to the friction damping portion 60 and the elastic rubber portion 50 to a predetermined size, as shown in FIG. The disc spring laminated body 41 and a pressure contact force adjusting mechanism 44 that adjusts the elastic force of the disc spring laminated body 41 are provided.

  The disc spring laminated body 41 has a plurality of disc spring units 42 </ b> U formed by aligning the orientations of a plurality of disc springs 42. Then, by appropriately setting the number of these units, the vertical direction of the units, the number of the disc springs 42 in the unit, and the like, the relationship between the deflection amount and the elasticity of the disc spring laminated body 41 can be obtained. It is uniquely determined (see FIG. 6). In the example of FIG. 3, two sets of disc spring units 42U including four disc springs 42 are used, and these disc spring units 42U and 42U are arranged in series with their directions reversed. Then, under the relationship between the amount of deflection and the elastic force, the amount of deflection applied to the disc spring laminated body 41 is adjusted by the pressure-contact force adjusting mechanism 44, thereby adjusting the pressure-contact force as the elastic force to an arbitrary value. Is possible.

  The pressure contact force adjustment mechanism 44 pushes down the upper pressure plate 45 and the lower pressure plate 46 by pressing the upper pressure plate 45 downward and a pair of upper and lower disk-shaped pressure plates 45, 46 arranged with the disc spring laminated body 41 interposed therebetween. And a pressurizing portion 47 that imparts deflection to the disc spring laminate 41 by contraction.

  Specifically, a cylindrical shaft 46a protruding upward is fixed at the center of the lower pressurizing plate 46, and this cylindrical shaft 46a is inserted into the central through hole 42a of the disc spring 42, and further, The disc spring stack 41 is also inserted into the through hole 45a in the center of the pressure plate 45 so as to be freely inserted and withdrawn, so that the disc spring laminated body 41 is held so as not to be dropped sideways when sandwiched between the upper and lower pressure plates 45 and 46. ing. A cylindrical portion 45b that protrudes upward is integrally formed along the entire circumference of the through hole 45a of the upper pressure plate 45, and this cylindrical portion 45b is bolted to the lower surface 1a of the building 1. It is screwed into a vertical insertion hole 47 a formed in the pressure part 47. That is, a female thread 47c is formed on the inner peripheral surface of the insertion hole 47a, and a male screw 45c is formed on the outer peripheral surface of the cylindrical portion 45b of the upper pressure plate 45 so as to be engaged with the female screw 47c. When the upper pressurizing plate 45 is screwed and rotated relative to the pressurizing portion 47, the upper pressurizing plate 45 is fed in the vertical direction by the screwing rotation like a so-called feed screw mechanism.

  Therefore, if the upper pressurizing plate 45 is screwed and rotated, and the upper pressurizing plate 45 is pushed downward by an amount corresponding to the screwing rotation amount, the disc spring laminated body 41 is given a vertical deflection, An elastic force is generated in the disc spring laminated body 41. The elastic force is applied to the friction damping portion 60 and the elastic rubber portion 50 as the pressure contact force by obtaining a reaction force from the building 1 through the upper pressure plate 45 and the pressure portion 47, and as a result, friction. The frictional force of the damping part 60 and the vibration isolation period by the elastic rubber part 50 are set. Incidentally, since the relationship between the deflection amount and the elastic force is known in advance as described above (see FIG. 6), the magnitude of the pressure contact force can be known by measuring the change in the deflection amount from the no-load state. be able to.

  FIG. 4 is a graph of vibration energy absorption history characteristics of the vibration isolator 10. That is, the graph is obtained by forcibly vibrating the upper and lower ends of the vibration isolator 10 horizontally with a predetermined amplitude (for example, ± 15 cm). The relative displacement in the direction is shown, and the vertical axis shows the horizontal force generated by the vibration isolator 10 against the horizontal vibration. Incidentally, the horizontal relative displacement is synonymous with the horizontal relative displacement between the building 1 and the foundation 3.

  In this example, the frictional force of the friction damping portion 60 is set to 10 TON as a target value by adjusting the pressure contact force by the disc spring portion 40. Therefore, when the absolute value of the external force of vibration is 10 TON or less, the friction damping portion 60 does not function without sliding, and the elastic rubber portion 50 functions exclusively. That is, the laminated rubber 51 of the elastic rubber portion 50 is deformed in the horizontal direction as shown by line segment AB, line segment CD, and line segment EF in FIG. Damping while increasing the period of vibration. When the absolute value of the external force of vibration exceeds 10 TON, the friction damping unit 60 functions, that is, the pair of friction plates 61 and 62 slide to each other, and the line segment DE and the line segment FC in FIG. As shown in FIG. 5, a frictional force of 10 TON is generated, and thereby the horizontal vibration of the building 1 is attenuated.

  Therefore, according to the vibration isolator 10, for a small earthquake with a horizontal seismic load of 10 TON or less, the elastic rubber portion 50 dampens the building 1 while being isolated, while the seismic load is reduced to 10 TON. The building 1 is vibrationally attenuated by the frictional damping unit 60 against a large earthquake that exceeds, and the building 1 is reliably vibration-isolated while being isolated, regardless of the magnitude of the earthquake load.

  Further, in the vibration isolator 10 of the first embodiment, the pressure contact force can be adjusted by the disc spring portion 40. Therefore, the friction force of the friction plates 61 and 62 and the horizontal rigidity Kh of the laminated rubber 51 by this adjustment are adjusted. Through this change, the above vibration energy absorption history characteristics can be freely set and changed.

  For example, if the pressure contact force is made higher than the above basic example (in the case of the frictional force target value 10 TON) indicated by the solid line in FIG. 5, the frictional force is set to 12.5 TON larger than the basic example, The horizontal stiffness Kh is set to a value smaller than that of the basic example, and as a result, the setting is changed to the vibration energy absorption history characteristic as shown by the dotted line in FIG. On the contrary, if the pressure contact force is made lower than that in the basic example, the frictional force is set to 7.5 TON smaller than that in the basic example, and the horizontal rigidity Kh is set to be larger than that in the basic example. As a result, the setting is changed to the vibration energy absorption history characteristic as shown by the one-dot chain line in FIG.

  Incidentally, in the first embodiment described above, a rolling bearing is used as the bearing portion 20 of the vibration isolator 10, but instead of this, a sliding bearing (a pair of upper and lower slides that slide on the sliding surface with a small sliding resistance) is used. A structure provided with a sliding plate) or laminated rubber may be used. Here, in the case of the former sliding bearing, the vertical gap G between the building 1 and the foundation 3 is maintained at a substantially constant interval as in the case of the rolling bearing of the first embodiment described above. In the case of rubber, since the laminated rubber itself can be expanded and contracted in the vertical direction, the interval of the vertical gap G varies with the rocking vibration of the building 1, and as a result, the disc spring portion 40. The deflection amount of the disc spring laminated body 41 also varies. Finally, the frictional force of the friction damping part 60 and the horizontal rigidity Kh of the elastic rubber part 50 change through the fluctuation of the elastic force of the disc spring laminated body 41. As a result, the frictional force and the vibration isolation period are targeted. There is a risk that the value cannot be maintained.

  In such a case, it is preferable to set the pressure contact force by utilizing the nonlinearity of the relationship between the load of the disc spring and the amount of deflection. FIG. 6 is a load-deflection curve showing the spring characteristics of the disc spring. This spring characteristic is a linear region (corresponding to the first range) in which the elastic force changes almost in proportion to the change of the deflection amount. It has a non-linear region (corresponding to the second range) smaller than the rate of change in the elastic force of this linear region. In particular, the latter non-linear region is a dead zone in which the elastic force hardly changes with the change in the deflection amount. Therefore, for example, if the deflection amount of the disc spring 42 of the disc spring laminated body 41 is set to the median deflection amount of the dead band, even if the deflection amount slightly fluctuates, the elastic force is maintained at a substantially constant value. As a result, the frictional force of the frictional damping part 60 and the vibration isolation period by the elastic rubber part 50 can be maintained substantially constant even under rocking vibration.

  By the way, when the former sliding bearing or the rolling bearing of the first embodiment is used as the bearing section 20, the vertical gap G between the building 1 and the foundation 3 is maintained substantially constant, so that the disc spring section The deflection amount of 40 disc spring laminated bodies 41 is also maintained at a constant value. Therefore, in this case, it is not particularly necessary to use the above-described dead band, that is, the deflection amount in the linear region of FIG. 6 may be set.

  FIG. 7 is a side sectional view of a modified example of the vibration isolator 10 of the first embodiment. In this modification, instead of the laminated rubber 51 of the elastic rubber portion 50 of FIG. 2, as shown in FIG. 7, a cylindrical viscoelastic rubber 55 (viscoelastic body) is formed with respect to the elastic rubber portion 50a of the friction damper portion 30a. Equivalent) is used, and other configurations are the same.

  And according to the vibration isolator 10a of this modification, the vibration energy of the building 1 is effectively absorbed by the large energy absorption action accompanying the shear deformation in the horizontal direction of the viscoelastic rubber 55 itself. The sex can be further enhanced.

  That is, FIG. 8 shows a graph of vibration energy absorption history characteristics of the vibration isolator 10a. By using the viscoelastic rubber 55, the line segment AB and line segment CD in which the viscoelastic rubber 55 is shear-deformed in the horizontal direction are shown. In the line segment EF, the displacement does not change linearly with respect to the force in the horizontal direction, and the displacement remains so as to draw a spindle shape, and the area of the region CDEF is increased by that amount. It is larger than the case of the first embodiment. Here, the size of the area of the region CDEF indicates the amount of energy absorption. From this, it can be seen that the vibration isolator 10a of this modification is superior in terms of energy absorption capability. Examples of the viscoelastic rubber include “VEM damper (acrylic polymer material): Sumitomo 3M Co., Ltd.” and “silicon rubber viscoelastic damper, diene rubber viscoelastic damper: Showa Electric Device Technology Co., Ltd. ) "Etc. can be applied.

<<< Vibration Isolation Device 10b of Second Embodiment >>>
FIG. 9 is a side sectional view of the vibration isolator 10b of the second embodiment. In the vibration isolator 10 of the first embodiment, the elastic rubber portion 50 is subjected to vibration isolation by shearing in the horizontal direction against a small earthquake load. However, in the configuration, the elastic rubber portion 50 is sheared and deformed not only by a small earthquake load but also by a wind load smaller than that, and as a result, the building 1 is easily shaken by the wind and the comfortability is deteriorated. There is a fear.

  Therefore, in the second embodiment, the auxiliary friction damper 70 is disposed in parallel with the elastic rubber portion 50 of the friction damper portion 30b, and this auxiliary friction damper 70 is applied to wind loads smaller than the earthquake load. Is configured to restrain the horizontal shear deformation of the elastic rubber portion 50 from being impossible. The difference from the first embodiment is that an auxiliary friction damper 70 is additionally provided, and other configurations are generally the same.

  As shown in FIG. 9, the auxiliary friction damper 70 is attached to the lower pressure plate 46 of the disc spring part 40, so that the auxiliary friction damper 70 straddles the laminated rubber 51 of the elastic rubber part 50 in the vertical direction. The laminated rubber 51 is arranged in parallel. That is, the upper end 71 a of the mounting rod 71 of the auxiliary friction damper 70 is screwed and fixed to the lower pressure plate 46, and the lower end 71 b of the mounting rod 71 is a through-hole of the cylindrical auxiliary friction member 72. The lower surface of the auxiliary friction member 72 is in contact with the upper surface of the lower friction plate 62 of the friction damping portion 60 with a predetermined pressure contact force in the vertical direction. Therefore, until the horizontal force as the horizontal external force exceeds the magnitude of the friction force between the auxiliary friction member 72 and the lower friction plate 62, the laminated rubber 51 of the elastic rubber portion 50 cannot be sheared in the horizontal direction. On the other hand, if it exceeds, the laminated rubber 51 shears and deforms in the horizontal direction as the auxiliary friction member 72 and the lower friction plate 62 slide.

  Here, the auxiliary friction member 72 is, for example, an ultra-high molecular weight polyethylene made of the same material as the upper friction plate 61, and the magnitude of the frictional force between the auxiliary friction member 72 and the lower friction plate 62 is the above-described pressure contact. It is adjusted by adjusting the force. That is, a nut member 74 with a pressure plate 73 is screwed to a portion of the mounting rod 71 above the auxiliary friction member 72, and a spring is interposed between the nut member 74 and the auxiliary friction member 72. A disc spring 75 is disposed as a member. Therefore, by rotating the nut member 74 in a threaded manner and moving the nut member 74 toward the auxiliary friction member 72, the disc spring 75 can be bent between the pressure plate 73 and the auxiliary friction member 72. The auxiliary friction member 72 is pressed against the lower friction plate 62 of the friction damping portion 60 by using the elastic force according to the amount of deflection as a pressing force. Therefore, the magnitude of the frictional force of the auxiliary friction damper 70 can be adjusted by adjusting the amount of deflection of the disc spring 75.

  The target value of the frictional force of the auxiliary friction damper 70 is set to a value smaller than the frictional force of the friction damping unit 60. More specifically, for example, it is set to a value between the average value of the wind load and the frictional force of the friction damping portion 60. And, for example, if the target value of the frictional force is set to 5 TON, as shown in the graph of vibration energy absorption history characteristics of FIG. This occurs with a width of 5 TON like the line segment EE2, and this restrains the shear deformation of the elastic rubber part 50 under the action of a horizontal force of 5 TON or less. As a result, the horizontal vibration of the building 1 due to wind is effectively suppressed. It becomes possible.

  Incidentally, the widths of the line segment AA2, the line segment CC2, and the line segment EE2 can be changed by adjusting the frictional force by the nut member 74, as is apparent from the above. Therefore, for example, if the frictional force of 5 TON is increased to 7.5 TON, the line segment AA2, the line segment CC2, and the line segment EE2 of the vibration energy absorption history characteristic are changed as shown by the dotted line in FIG. .

<<< Vibration Isolation Device 10c of Third Embodiment >>>
FIG. 11 is a side sectional view of the vibration isolator 10c of the third embodiment. In the vibration isolator 10 of the first embodiment, the pressure contact force of the disc spring portion 40 also acts on the laminated rubber 51 of the elastic rubber portion 50. In this third embodiment, the laminated rubber 51c of the elastic rubber portion 50c is used. In contrast, a rolling support member 81 is arranged in parallel, and the rolling support member 81 receives the pressure contact force instead of the laminated rubber 51c. Therefore, the pressure contact force does not act on the laminated rubber 51c, that is, the height of the laminated rubber 51c is substantially maintained at a natural length where no vertical load acts, so that the horizontal rigidity Kh is a predetermined value (laminated rubber). Therefore, the vibration isolation period of the elastic rubber portion 50c can be reliably maintained at a desired target value.

  As shown in FIG. 11, the elastic rubber portion 50c includes a laminated rubber 51c, a pair of upper and lower flange plates 52 and 53 fixed with the laminated rubber 51c sandwiched therebetween, and a pair of upper and lower flange plates 52 and 53. It is mainly composed of a rolling support member 81 disposed so as to surround the periphery of the laminated rubber 51c while being interposed in the vertical gap Gc.

  The laminated rubber 51c is arranged with its plane center aligned with the plane center of the flange plate 52, and its three-dimensional size is significantly smaller than the laminated rubber 51 of the first embodiment described above in terms of the outer diameter. It has become. The reason for this reduction is that the laminated rubber 51c of the third embodiment does not receive the pressure contact force from the disc spring portion 40, and therefore does not require a high rigidity that does not buckle the pressure contact force. Therefore, in the third embodiment, the horizontal rigidity Kh of the laminated rubber 51c is reduced especially with the reduction of the planar size of the laminated rubber 51c, so that the vibration isolation period by the elastic rubber portion 50c is remarkably increased. The

  On the other hand, the rolling support member 81 includes a plurality of steel balls 82, a pair of upper and lower rolling plates 83 and 84 on which the steel balls 82 roll while sandwiching the plurality of steel balls 82 up and down, and the plurality of steel balls 82. And a pair of inner and outer annular guide members 85 and 86 for preventing falling off from the rolling route. Since the height of the rolling support member 81 is set to be substantially the same as the height of the natural length of the laminated rubber 51c, as described above, the pressure contact force from the disc spring portion 40 is exclusively applied to the rolling support member 81. Therefore, the laminated rubber 51c can be sheared and deformed in the horizontal direction according to the horizontal force while the height of the laminated rubber 51c is maintained at a natural length.

  Incidentally, as for the inner annular guide member 85, the upper and lower edges on the inner peripheral side thereof are chamfered in a tapered shape to form a pair of upper and lower chamfered portions 85a and 85b. This is because when the laminated rubber 51c is sheared and deformed in the horizontal direction and its outer shape becomes a parallelogram in the longitudinal section, interference with the inner annular guide member 85 is avoided, and the laminated rubber 51c This is to ensure free shear deformation.

  Since the vibration energy absorption history characteristic of the vibration isolator 10c is qualitatively substantially the same as that in FIG. 4 described above, the description thereof is omitted.

  12A is a side sectional view of a first modification of the vibration isolator 10c of the third embodiment, and FIG. 12B is a sectional view taken along line BB in FIG. 12A. In each figure, only the friction damper portion 30d of the vibration isolator 10d is shown.

  In the first modification, a viscoelastic rubber 91 is additionally provided in parallel with the laminated rubber 51c of the elastic rubber portion 50c of the third embodiment, thereby improving the attenuation of horizontal vibration. .

  The viscoelastic rubber 91 is a cylindrical body having the same height as the laminated rubber 51c. A plurality of viscoelastic rubbers 91 are disposed so as to surround the laminated rubber 51 c while being interposed in the vertical gap Gc between the upper and lower flange plates 52 and 53. However, since the rolling bearing member 92 that holds the vertical gap Gc between the upper and lower flange plates 52 and 53 must be disposed at a position surrounding the periphery of the laminated rubber 51c, in the first modification example, Rolling support members 92 and viscoelastic rubbers 91 are alternately arranged along the outer periphery of the laminated rubber 51c while being spaced apart from each other. Each rolling support member 92 includes a steel ball 95 and a pair of upper and lower rolling plates 93 and 94 on which the steel ball 95 rolls while sandwiching the plurality of steel balls 95 up and down.

  Each of the rolling plates 93, 94 is provided with vertical wall portions 93a, 94a along the outer peripheral edge thereof, and the falling off of the steel balls 95 to the side is restricted by the wall portions 93a, 94a. . Therefore, the steel ball 95 supports the pressure contact force of the disc spring portion 40 while rolling between the pair of upper and lower rolling plates 93 and 94, and thereby the laminated rubber 51c and the viscoelastic rubber are caused by the action of the pressure contact force. 91 is released.

  The vibration energy absorption history characteristic of the vibration isolator 10d is qualitatively substantially the same as that in FIG. 8 described above, and a description thereof will be omitted.

  FIG. 13 is a side sectional view of a second modification of the vibration isolator 10c of the third embodiment, and shows only the friction damper portion 30e of the vibration isolator 10e as in FIG. 12A described above.

  In the second modification, a mechanical stopper 101 that mechanically defines a deformation limit of shear deformation in the horizontal direction is added to the elastic rubber portion 50c of the third embodiment. That is, in the second modification, when the horizontal relative displacement between the upper end and the lower end of the elastic rubber portion 50e reaches a predetermined value, the mechanical stopper 101 acts to restrict further shear deformation to be impossible. ing.

  The mechanical stopper 101 includes a cylindrical body 102 extending downward from the outer peripheral portion of the upper flange plate 52 of the elastic rubber portion 50e as a main body. And the ring-shaped shock absorbing material 103 is attached to the inner peripheral surface of the lower end part of this cylindrical body 102 over the whole circumference, and the inner peripheral surface of this shock absorbing material 103 is separated by a predetermined gap S, It faces the outer peripheral surface of the lower flange plate 53.

  Accordingly, the horizontal relative displacement between the upper flange plate 52 as the upper end and the lower flange plate 53 as the lower end of the elastic rubber portion 50c is allowed by the size of the predetermined gap S, that is, by the size of the predetermined gap S. The shearing deformation in the horizontal direction of the laminated rubber 51c is allowed. When the inner peripheral surface of the cushioning material 103 comes into contact with the outer peripheral surface of the lower flange plate 53, further shear deformation of the laminated rubber 51c is restricted.

  Here, when the magnitude of the horizontal external force acting at the time of contact is larger than the friction force of the friction damping portion 60, the upper and lower friction plates 61, 62 of the friction damping portion 60 slide. As a result, the vibration isolator 10e as a whole is relatively displaced in the horizontal direction. However, when the frictional force is less than the frictional damping portion 60, the frictional damping portion 60 does not slide, and the relative displacement is maintained even in the vibration isolator 10e as a whole.

  FIG. 14 is a graph of vibration energy absorption history characteristics of the vibration isolator 10e according to the second modification. As can be seen from a comparison with FIG. 4, a state in which horizontal displacement is not possible due to the additional installation of the mechanical stopper 101 is newly generated such as a line segment A3B3, a line segment C3D3, and a line segment E3F3.

  Incidentally, if the laminated rubber 51c of the elastic rubber portion 50e of the second modification is replaced with a viscoelastic rubber, the vibration energy absorption characteristic changes as shown in FIG. 15 by changing the line segment CC3 and the line segment EE3. Absorption capacity is further increased.

=== Other Embodiments ===
As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, The deformation | transformation as shown below is possible in the range which does not deviate from the summary.

  In the first embodiment described above, as an example of the friction damper portion 30 of the vibration isolator 10, the disc spring portion 40, the elastic rubber portion 50, and the friction damping portion, which are three components included in the friction damper portion 30, are provided. 60 shows a configuration arranged in series from top to bottom in this order (see the side view of FIG. 16A), but this order of arrangement may be changed. For example, in addition to FIG. 16A, FIG. Five aspects are possible as shown in the side view of FIG. 18B.

  That is, the arrangement order of the first embodiment shown in FIG. 16A is reversed to the top and bottom, and as shown in FIG. 16B, the friction damping part 60, the elastic rubber part 50, and the disc spring part 40 are arranged in order from top to bottom. Also good. Further, as shown in FIG. 17A, the order of arrangement from top to bottom may be the elastic rubber part 50, the disc spring part 40, and the friction damping part 60, or the arrangement order of FIG. As shown in FIG. 17B, the friction damping portion 60, the disc spring portion 40, and the elastic rubber portion 50 may be arranged in order. Further, as shown in FIG. 18A, the order of the disc spring portion 40, the friction damping portion 60, and the elastic rubber portion 50 may be arranged, or the arrangement order of FIG. Alternatively, the elastic rubber portion 50, the friction damping portion 60, and the disc spring portion 40 may be arranged in order.

  In the above-described embodiment, the disc spring 42 has been described as having a spring characteristic having a linear region and a non-linear region like the load-deflection curve in FIG. 6, but the present invention is directed to such an embodiment. It is not limited. That is, when a sliding bearing or a rolling bearing is used as the bearing portion 20, the vertical gap G between the building 1 and the foundation 3 is maintained almost constant, so the disc spring has a small proportion of the nonlinear region, It is possible to use a material in which most of the region shows a spring characteristic in a linear region.

It is a conceptual diagram of the building 1 to which the vibration isolator 10 of 1st Embodiment was applied. It is a sectional side view of the vibration isolator 10 of 1st Embodiment. It is a graph which shows the vertical load P dependence of the horizontal rigidity Kh of the laminated rubber 51. It is a graph of the vibration energy absorption history characteristic of the vibration isolator 10 of 1st Embodiment. It is a graph of the vibration energy absorption history characteristic of the vibration isolator 10 of 1st Embodiment. It is a load-deflection curve which shows the spring characteristic of a disc spring. It is a sectional side view of the modification of the vibration isolator 10 of 1st Embodiment. It is a graph of the vibration energy absorption history characteristic of the vibration isolator 10a of a modification. It is a sectional side view of the vibration isolator 10b of 2nd Embodiment. It is a graph of the vibration energy absorption history characteristic of the vibration isolator 10b of 2nd Embodiment. It is a sectional side view of the vibration isolator 10c of 3rd Embodiment. FIG. 12A is a side sectional view of a first modification of the vibration isolator 10c of the third embodiment, and FIG. 12B is a sectional view taken along line BB in FIG. 12A. It is a sectional side view of the 2nd modification of the vibration isolator 10c of 3rd Embodiment. It is a graph of the vibration energy absorption history characteristic of the 2nd modification of the vibration isolator 10c of 3rd Embodiment. It is a graph of the vibration energy absorption history characteristic obtained when the laminated rubber 51e of the said 2nd modification is replaced | exchanged for viscoelastic rubber. 16A and 16B are explanatory diagrams of variations in the arrangement order of the disc spring part 40, the elastic rubber part 50, and the friction damping part 60 included in the vibration isolation device 10 of the first embodiment. FIG. 17A and FIG. 17B are explanatory diagrams of variations of the arrangement order. 18A and 18B are explanatory diagrams of variations of the arrangement order.

Explanation of symbols

1 building (object to be isolated), 1a underside,
3 Substructure (basic), 3a Top surface,
10 vibration isolator, 10a vibration isolator, 10b vibration isolator,
10c vibration isolator, 10d vibration isolator, 10e vibration isolator,
20 bearing part, 21a receiving seat, 21b receiving seat,
23 rolling plates, 24 rolling plates, 25 steel balls,
30 Friction damper part, 30a Friction damper part, 30b Friction damper part,
30c Friction damper part, 30d Friction damper part, 30e Friction damper part,
40 disc springs, 41 disc spring laminates,
42 disc spring, 42U disc spring unit, 42a through hole,
44 Pressure contact force adjustment mechanism (adjustment mechanism),
45 upper pressure plate, 45a through hole, 45b cylindrical part,
46 lower pressure plate, 46a shaft,
47 pressure part, 47a insertion hole, 50 elastic rubber part,
50a elastic rubber part, 50c elastic rubber part, 50e elastic rubber part,
51 Laminated rubber (elastic body), 51a Steel plate, 51b Rubber layer,
51c Laminated rubber (elastic body), 52 Upper flange plate, 53 Lower flange plate,
55 viscoelastic rubber (elastic body), 60 friction damping part,
61 upper friction plate (friction member), 62 lower friction plate (friction member),
70 Auxiliary friction damper, 71 Mounting rod,
71a upper end, 71b lower end, 72 auxiliary friction member, 72a through hole,
73 pressure plate, 74 nut member, 75 disc spring (spring member),
81 rolling support members (holding members), 82 steel balls,
83 Rolling plate, 84 Rolling plate,
85 circular guide member, 85a chamfered portion,
86 annular guide member, 86a chamfered portion,
91 viscoelastic rubber (elastic body), 92 rolling support member (holding member),
93 rolling plate, 93a vertical wall,
94 rolling plate, 94a vertical wall, 95 steel balls,
101 mechanical stopper, 102 cylindrical body, 103 cushioning material,
G Vertical gap, Gc Vertical gap, S Predetermined gap

Claims (6)

A support portion that supports the weight of the vibration isolation object while allowing horizontal movement of the vibration isolation object, and a friction damper that suppresses horizontal movement of the vibration isolation object include the vibration isolation object and its lower part. A vibration isolator which is interposed in parallel with the vertical gap between the lower structure and
The friction damper part is
A pair of upper and lower friction members that slide in the horizontal direction according to the relative displacement in the horizontal direction between the object to be isolated and the lower structure;
An elastic body that is arranged in series with the pair of friction members and has an upper end and a lower end that are relatively displaced in the horizontal direction in response to a horizontal force;
A disc spring disposed in series with respect to the pair of friction members and imparting a vertical pressure contact force to the pair of friction members;
And an adjusting mechanism for adjusting the magnitude of the pressure contact force by adjusting a deflection amount of the disc spring. The vibration isolator according to claim 1,
An auxiliary friction damper is provided in parallel with the elastic body,
The magnitude of the frictional force when the auxiliary friction damper slides in the horizontal direction is smaller than the magnitude of the frictional force when the pair of friction members slide in the horizontal direction,
When the auxiliary friction damper does not slide, the auxiliary friction damper restrains the relative displacement in the horizontal direction between the upper end and the lower end of the elastic body to be impossible. A vibration isolator according to claim 2,
The pair of friction members and the elastic body are connected vertically.
The auxiliary friction damper includes an auxiliary friction member provided in one of the pair of friction members so as to be slidable in a horizontal direction, and is arranged in series with the auxiliary friction member so as to be perpendicular to the auxiliary friction member. And a spring member for applying a pressure contact force in the direction. A vibration isolator according to any one of claims 1 to 3,
The vibration isolator is a viscoelastic body. A vibration isolator according to any one of claims 1 to 4,
The support member that receives the pressure contact force is not arranged in parallel with the elastic body,
The ratio of the change in the elastic force to the change in the deflection amount of the disc spring is smaller in the deflection amount in the second range than in the first range,
The vibration isolation device, wherein the amount of deflection of the disc spring is adjusted by the adjustment mechanism so as to be within the second range. A vibration isolator according to any one of claims 1 to 4,
A holding member that holds the distance between the upper end and the lower end of the elastic body at the natural length of the elastic body while allowing horizontal relative displacement between the upper end and the lower end of the elastic body. A vibration isolator provided in parallel with an elastic body.

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